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1

Hauck, Christian. "Konzeption und Entwicklung eines Konferenzführers für Großereignisse als mobile Applikation für die ICC 2013." Master's thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-86754.

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Das Betriebssystem Android bietet, aufgrund der stetig steigenden Zahl der verfügbaren mobilen Geräte auf Basis dieses System und der ebenfalls stark steigenden Zahl der Nutzer solcher Geräte, eine sehr gute Grundlage zur Entwicklung diverser mobiler Anwendungen. Es kann dabei für jeden erdenklichen Bereich des alltäglichen Lebens, vor allem Freizeit, aber auch Arbeit, eine App auf Grundlage von Android entwickelt werden. Im Bereich der mobilen Eventguides gibt es aktuell noch Entwicklungsbedarf bei den angebotenen mobilen Applikationen. So gibt es zahlreiche Anwendungen für Messen, Konferenzen oder Festivals, allerdings unterscheiden sich diese stark in ihren Funktionen und vor allem in der Darstellung von Karten und Plänen. Häufig werden solche Apps auf Grundlage eines Frameworks erstellt, welches es ermöglicht die App an verschiedene Veranstaltungen anzupassen. Die vorliegende Arbeit beschreibt die Implementierung eines Konferenzführers für die Internationale Kartographische Konferenz 2013 in Dresden. Grundlage für die Implementierung ist dabei die Betrachtung von Orientierungsmethoden und Navigationsanwendungen für Fußgänger im In- und Outdoorbereich und auf Großveranstaltungen. Hierzu werden bereits vorhandene Apps aus dem Bereich Veranstaltungen untersucht. Neben den allgemeinen Funktionen wird ein Augenmerk auf die kartographischen Funktionen solcher Apps gelegt. Im Rahmen der Arbeit wird ein Framework, auf Basis von Android, entwickelt, welches die Erstellung von mobilen Anwendungen für verschiedene Großereignisse ermöglicht. Dieses Framework wird speziell an die Internationale Kartographische Konferenz 2013 angepasst und liefert als Ergebnis eine App, die als digitaler Konferenzführer genutzt werden kann<br>The Android operating system offers, due to the increasing number of available mobile devices based on this system and also the rapidly increasing number of users of such devices, a very good basis for the development of various mobile applications. It can be relevant to every conceivable area of everyday life, especially leisure, but also work to develop an app based on Android. It currently still requires development of the offered mobile applications in the area of mobile event guides. There are numerous applications for trade shows, conferences and festivals, but they differ greatly in their functions and, above all in the presentation of maps and plans. Often, such apps are created based on a framework that allows the app to adapt to different events. The present paper describes the implementation of a conference guide for the International Cartographic Conference 2013 in Dresden. Basis for the implementation is the consideration of methods of orientation and navigation applications at indoor and outdoor areas for pedestrians and on major events. To this end, existing applications from the category large events will be studied. Besides the general features a focus is placed on the cartographic features of such apps. A framework, based on Android, which allows the creation of mobile applications for various large events, will be created as part of the work. This framework is adapted to the International Cartographic Conference 2013 and delivers as a result an application that can be used as a digital conference guide
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Thys, An. "Assessment of new potential therapeutic targets in murine and cellular models of gastrointestinal stromal tumors." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/220502.

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The present thesis project focused on the preclinical study of Neurotensin receptor 1 (Ntsr1), Endoglin/CD105 (Eng), Glypican 6 (Gpc6) and Sprouty homolog 4 (Spry4) as potential markers or molecular targets for future therapeutic interventions of gastrointestinal stromal tumors (GIST). Ntsr1 expression was characterized was reported in a paper that I co-authored entitled “Neurotensin receptor 1 is expressed in gastrointestinal stromal tumors but not in interstitial cells of Cajal.” by Gromova et al. PLOS ONE, 2009. As radio-labeled NTSR1 ligand analogues have already been reported for whole-body imaging and therapeutic interventions, prompting us to investigate NTSR1 as a target for in vivo imaging of GIST.Next, expression of Eng was characterized in the KitK641E murine GIST model, human GIST, GIST882 and BaF3 cells. This study has been reported in “Endoglin/CD105 is expressed in KIT positive cells in the gut and gastrointestinal stromal tumors” by Gromova et al. JCMM, 2011, a paper I co-authored. As result, an American start-up approached us to assess their proprietary compound targeting ENG on GIST882 cells. However, concerns were raised about possible non-selective action and the project was stalled by the company.Subsequently, GIST tissue microarrays were examined by immunohistochemistry using the sole commercially available GPC6 antibody. No statistical correlation could be found between GPC6-ir and GIST clinic-pathological features and concerns were raised about the reliability of the GPC6 antibody used. Ultimately, Spry4 was investigated in the last part of my thesis. In vitro, we have demonstrated that Spry4 is specifically upregulated by the ERK pathway in GIST882 cells. In vivo, Spry4 deficient mice showed an ICC hyperplasia in antrum and colon, using a new ICC quantification method developed in the lab, which was reminiscent of the oncogenic GIST murine model KitK641E. Similarities between Spry4 KO and KitK641E heterozygous animals were even further emphasized by functional studies, as both genotypes showed a delay in transit time. This study lead to the publication “Hyperplasia of interstitial cells of Cajal in Sprouty homolog 4 deficient mice” by Thys et al. 2015, PLOS ONE.<br>Doctorat en Sciences biomédicales et pharmaceutiques (Médecine)<br>info:eu-repo/semantics/nonPublished
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Dierckx, Marie. "Marine ice rheology from deformation experiments of ice shelf samples using a pneumatic compression device: implications for ice shelf stability." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209505.

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Antarctic ice shelves control the ice flux from the continent to the ocean. As such, they play a major role in the stability of the ice sheet and its potential contribution to sea level rise, especially in the context of global change. Below some of these ice shelves, marine ice can be found which is a product of the Deep Thermohaline Circulation. Due to its specific genetic process, marine ice has intrinsic physical (grain size, ice fabric, bubble content, ) and chemical (impurities, water stable isotopes) properties, that differ from those of 'meteoric ice' formed on the continent through snow metamorphism or 'sea ice' resulting from sea water freezing at the ocean-atmosphere surface. Until now however, the effect of these specific properties on marine ice rheology is still very poorly understood.<p><p>The principal objective being to include realistic mechanical parameters for marine ice in ice shelf flow models, uniaxial compression experiments have been performed on various types of marine ice samples. Technical developments are an important component of this thesis has they were necessary to equip the laboratory with the appropriate tools (pneumatic rig, automatic ice fabric data handling).<p><p>Results from experimental compression on isotropic marine ice show that it represents the higher boundary for meteoric ice viscosity throughout the whole temperature range, thereby validating Cuffey and Paterson's relationship with an enhancement factor equals to 1.<p><p>Marine ice is however often quite anisotropic, showing elongated crystals and wide single maximum fabric, that should impact its mechanical properties. Experiments on pre-oriented marine ice samples have therefore been carried out combining the study of epsilon_{oct} vs. tau_{oct} with a thorough analysis of microstructural data 'before' and 'after' the experiment. <p><p>Depending on the orientation of the sample in the applied stress field and on the intensity of the latter, anisotropic marine ice can be harder or softer than its isotropic counterpart, with n=4 often observed in Glen's flow law. Associating the experimental geometrical settings to potential natural equivalent, results suggest that anisotropic marine ice would strengthen ice shelf flow in most areas (for a same given temperature), apart from suturing areas between individual ice streams as they merge to form the ice shelf, where it could become weaker than meteoric ice in certain circumstances.<p><p>Finally, preliminary sensitivity studies, using a simple ice shelf model with our experimental parameters of Glen's flow law have allowed us to discuss the potential impact of rift location, rift size and thermal regime in the ice shelf behavior.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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Zhou, Jiayun. "The physical and biological controls on the distribution of gases and solutes in sea ice from ice growth to ice decay." Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209219.

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The ongoing changes in the extent and the properties of sea ice, associated with the warming climate, are affecting the polar ecosystem and the interactions between the atmosphere, sea ice and the underlying waters. How sea ice biogeochemistry will change in the foreseeable future is currently uncertain, but is a crucial problem to tackle.<p>To better understand how sea ice biogeochemistry could change, we investigated the factors regulating the distribution of some dissolved compounds (e.g. nutrients, dissolved organic matter (DOM)) and gaseous compounds (e.g. Ar, O2, N2, CH4) in sea ice, from ice growth to ice decay. The results were obtained from a 19-day indoor experiment in Hamburg (Germany) and a five-month-long field survey in Barrow (Alaska). They were then compared to the physical properties of the ice (temperature, salinity, and other derived parameters such as brine volume fraction) and different biological parameters (bacterial activity, bacterial abundance, chlorophyll-a and phaeopigments).<p>Our work indicates that the physical properties of sea ice exert a strong influence on the distribution of the biogeochemical compounds in the ice, through their impact on brine dynamics, gas bubble formation and ice permeability. We have described 4 stages of brine dynamics, which affect the distribution of the dissolved compounds (e.g. silicate and DOM) in sea ice. However, inert gas (Ar) shows a different dynamic in comparison to the dissolved compounds, indicating a different transport pathway. We suggest that the formation of gas bubbles in sea ice is responsible for that different transport pathway, because gas bubbles should move upward owing to their buoyancy in comparison to brine, while dissolved compounds are drained downward due to gravity. Our observations further indicate that the critical permeability threshold for the upward gas bubble transport should range between 7.5 and 10 % of brine volume fraction, which is higher than the 5 % suggested for the downward brine transport. Increasing ice permeability and prolonged gas exchange tend to draw gas concentrations toward their solubility values, except when the under-ice water is supersaturated relative to the atmosphere (e.g. CH4) or when in-situ production occurs in sea ice (e.g. O2).<p>Because ammonium and O2 obviously accumulate in the ice layers where convection is limited, we suggest that the changes of these biogeochemical compounds in sea ice depend on the competing effect between the physical transport and the biological activity; the biological impact on these biogeochemical compounds in sea ice is obvious when the biological production rate exceeds largely the physical transport rate. We further discussed on the potential of using Ar and N2 as inert tracers to correct the physical controls on O2 and to determine the net community production in sea ice.<p>In addition to the physical and biological controls, the chemical properties of some biogeochemical compounds (e.g. nitrate, ammonium, DOM) may further influence their distribution in sea ice; further investigations are however needed to confirm this.<p>Finally, based on our findings, we present an update of the processes regulating the distribution of gases in sea ice, with references to recent observations supporting each of the process. We also provide some insights on how sea ice biogeochemistry could change in the future and the research priorities for an accurate quantification of these changes.<p><p>Les changements dans l’extension et les propriétés de la glace de la mer, liés au réchauffement climatique, affectent l’écosystème polaire, ainsi que les interactions entre l’atmosphère, la glace de mer et l’eau sous-jacente. Cependant, des incertitudes subsistent quant aux changements potentiels qui affecteront la biogéochimie de la glace de mer dans un futur proche.<p>Afin de mieux comprendre les changements potentiels qui affecteront la biogéochimie de la glace de mer, nous avons étudié les facteurs qui influencent la distribution de certains composés dissouts (e.g. nutriments, matière organique dissoute (DOM)) et gazeux (e.g. Ar, O2, N2, CH4) au sein de la glace de mer, depuis la croissance de la glace, jusqu’à sa fonte. Les résultats ont été obtenus à partir d’une expérience de 19 jours dans un bassin expérimental à Hambourg (Allemagne) et une étude de terrain de 5 mois à Barrow (Alaska). Ils ont été ensuite comparés aux propriétés physiques de la glace (température, salinité et autres paramètres dérivés) et à des paramètres biologiques (activité bactérienne, abondance bactérienne, chlorophylle-a et phaeopigments).<p>Nos travaux ont montré que les propriétés physiques de la glace exercent une forte influence sur la répartition des composes biogéochimiques dans la glace de mer, à travers leur impact sur la dynamique des saumures, la formation de bulles de gaz et la perméabilité de la glace. Nous avons décrit 4 stades dans la dynamique des saumures qui influencent la distribution des composés dissouts (e.g. silice et DOM) dans la glace. Cependant, le gaz inerte étudié (Ar) montre une dynamique différente de celle des composés dissouts, indiquant un mécanisme de transport différent. Nous suggérons que la formation de bulles de gaz dans la glace de mer est le mécanisme responsable de cette différence, parce que les bulles de gaz devraient migrer vers le haut, à cause de leur différence de densité par rapport aux saumures, alors que les saumures sont drainées vers le bas à cause de la gravité. Nos observations montrent également que le seuil critique de perméabilité pour l’ascension des bulles de gaz devrait se trouver entre 7.5 et 10 % de volume relatif en saumure ;seuil qui est plus élevé que les 5 % suggérés pour le transport de saumure vers le bas. L’augmentation de la perméabilité de la glace et les échanges de gaz prolongés tendent à amener les concentrations de gaz vers leur valeur de solubilité, sauf lorsque l’eau sous-jacente présente une sursaturation parrapport à l’atmosphère (e.g. CH4), ou lorsque une production in-situ se produit au sein de la glace (e.g. O2).<p>Etant donné que l’ammonium et O2 s’accumulent clairement dans les couches de glace où la convection est limitée, nous suggérons que les variations de ces composés biogéochimiques dans la glace dépendent de la balance entre le transport physique et l’activité biologique ;l’impact de cette dernière sur les composés biogéochimiques est particulièrement visible lorsque le taux de production biologique du composé excède largement la vitesse d’élimination du composé par le transport physique. Nous avons ensuite discuté du potentiel d’utiliser Ar et N2 comme traceurs inertes pour corriger l’impact des processus physiques sur les variations de O2, afin de déterminer la production communautaire nette dans la glace de mer.<p>Les propriétés chimiques de certains composés biogéochimiques (e.g. nitrate, ammonium, DOM) pourraient également influencer leur répartition au sein de la glace de mer, en plus des processus physiques et biologiques. Cependant, il est nécessaire d’avoir plus d’études à ce sujet pour confirmer cela.<p>Enfin, sur base de nos résultats, nous présentons une mise à jour des processus qui régulent la répartition des gaz dans la glace de mer, avec des références à des observations récentes qui illustrent chacun des processus. Nous donnons également un aperçu des changements qui pourraient affecter la biogéochimie de la glace de mer à l’avenir, et des pistes de recherches pour une quantification précise de ces changements.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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Lemaire-Ronveaux, Denyse. "The dynamics of a small antartic ice shelf as indicated by an ice composition study." Doctoral thesis, Universite Libre de Bruxelles, 1992. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212907.

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Khazendar, Ala. "Marine ice formation in rifts of antartic ice shelves :a combined laboratory study and modeling approach." Doctoral thesis, Universite Libre de Bruxelles, 2000. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211759.

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Van, Liefferinge Brice. "Thermal state uncertainty assessment of glaciers and ice sheets: Detecting promising Oldest Ice sites in Antarctica." Doctoral thesis, Universite Libre de Bruxelles, 2018. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/268026.

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In a warming world, glaciers and ice sheets have an increasingly large influence on the environment, particularly through their contribution to sea level rise. Their response to anthropogenic climate change, in addition to natural variability, has a critical impact on dependent populations and will be key to predict future climates. Understanding the past natural transitions is also important as if the natural variability of the climate system is not well understood, we stand little change of accurately predicting future climate changes, especially in the context of rapid global warming. Ice cores represent the best time capsules for the recovery of paleo-climate informations. For that, the recovery of a suitable 1.5 million-year-old ice core in Antarctica is fundamental to better understand the natural climate reorganisation which occurred between 0.9 and 1.2 Ma. Constraining the englacial and basal temperature evolution of glaciers and ice sheets through time is the first step in understanding their temporal stability and therefore potential impacts on climate. Furthermore, obtaining the best constraints on basal conditions is essential as such million-year-old ice will be located very near to the bedrock, where the thermal regime has the strongest impact. However, measurements of current englacial and basal temperature have only been obtained at a few drill sites for glaciers and ice sheets. We must therefore turn to thermodynamical models to provide theoretical and statistical constraints on governing thermal processes. Thermodynamical models rely on a suite of governing equations, which we describe in this thesis. Our first study area is the McCall glacier, in Alaska (USA), where we show that the glacier cooled down in the warming climate of the last 50 years using a 1D thermodynamical model. We calculate the present-day englacial temperature distribution using recently acquired data in the form of englacial temperature measurements and radio-echo sounding surveys of the glacier. We show the important of absence of latent heat release due to the refreezing of meltwater inside an active surface layer and reconstruct the last 50 years of equilibrium line altitude (ELA) elevation changes. In the context of Beyond Epica Oldest Ice, a European project aimed at recovering a 1.5 million year-old ice core, we propose for the first time a map of the location of adequate drilling sites for the entire Antarctic Ice Sheet. We use a 3D thermomechanical model to calculate a new basal temperature map of the Antarctic Ice Sheet, as well as a 1D thermodynamical model to constrain the poorly known geothermal heat flux (GHF). These combined model runs use the latest acquired data sets for the GHF, ice flow velocity, ice thickness and subglacial lakes. In order to take into account 2 Ma of Antarctic climate history, we use a transient 1D thermodynamical model to provide constraints on GHF by calculating the maximum value of GHF allowed to keep frozen basal conditions everywhere underneath the ice sheet. These values are then statistically compared to published GHF data sets to propose a probabilistic map of frozen and thawed bedrock locations. This transient model uses high spatial resolution radar data acquired over the Dome Fuji and Dome C regions to examine their likelihood of having preserved 1.5-million-year ice. We define a number of important criteria such as GHF, bedrock variability, ice thickness and other parameter values for Oldest Ice survival. We anticipate that our methods will be highly relevant for Oldest Ice prospection in other areas of the ice sheet that so far remain little or un-surveyed, as well as for the thermal modelling of other glaciers and ice sheets, and in particular, of the Greenland Ice Sheet.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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Aquino, Quispe Umbelina Isabel, and Cabrera Gabriela Sheyla Quijandría. "Factores que influyeron en las exportaciones de uva fresca de las Pymes en la Región Ica: Periodo 2013-2017." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/626136.

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La presente investigación tiene el propósito de analizar los factores que influyen en las exportaciones de uva fresca de las Pymes en la Región Ica, como una alternativa que permita ayudar a las Pymes no exportadoras a buscar estos factores tanto internos como externos y que tienen variables que se relacionan y pueden ser fundamentales al momento de la internacionalización de una Pyme y así incrementar los volúmenes de exportación. La importancia de esta investigación radica en contribuir a que las Pymes puedan aumentar sus exportaciones e ingresos anuales, además, se tiene como finalidad de poder demostrar que existe potencial en los cuatro factores expuestos y que se desarrollan para tener un mayor alcance de cómo influyen en la exportación de las Pymes. Para el desarrollo de la investigación se realizó una encuesta con escala de Likert a una muestra de 50 Pymes exportadoras ubicadas en la Región Ica con la finalidad de tener mayor conocimiento y poder analizar los resultados mediante el método cuantitativo del coeficiente de Spearman.<br>This research is intended to analyze the factors influencing the exports of fresh grapes from SMEs (Small and Medium Business) in the Ica Region, as an alternative to help non-exporting SMEs to look for these internal and external factors and that have variables that are related and can be fundamental at the moment of the internationalization of a SME and thus increase the volumes of the export. The main aspects of this research lies in helping SMEs increase their exports and annual income. In addition, it objectives to demonstrate that there is potential in the four factors that are available to have a greater scope. The export of SMEs. The importance of this research lies in helping SMEs increase their exports and annual income, in addition, it aims to demonstrate that there is potential in the four factors that are available to have a greater scope in the export of SMEs. For the development of the research, a survey with a Likert scale was conducted to a sample of 50 exporting SMEs located in the Ica Region in order to have a greater knowledge and to analyze the results by means of the quantitative Spearman coefficient.<br>Tesis
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Berger, Sophie. "Stability of Antarctic ice shelves: A case study of the Roi Baudouin Ice Shelf, Dronning Maud Land, East Antarctica." Doctoral thesis, Universite Libre de Bruxelles, 2017. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/258789.

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The Antarctic ice sheet is increasingly contributing to sea-level rise because of accelerated mass losses at its floating extensions -- its ice shelves. By floating while remaining attached to the grounded ice sheet, ice shelves buttress (i.e. restrain) the inland ice in such a way that ice-shelf losses lead to accelerated ice discharge in the ocean. This thesis investigates the stability of Antarctic ice shelves -- so crucial for the stability of the entire ice sheet -- using the Roi Baudouin Ice Shelf (RBIS), Dronning Maud Land, East Antarctica, as a case study. The RBIS has remained relatively stable over the last millennia and presents various kilometre-scale features (pinning point, ice-shelf channels and englacial lakes) with potential impact on its present and future stability.We first derive a horizontal velocity field, combining interferometry and speckle tracking with Synthetic Aperture Radar images from ERS 1/2 and ALOS-PALSAR, respectively. The resulting velocities and associated shear-strain rates represent the most detailed fields, currently available for the RBIS and clearly resolve small-scale features of the RBIS: significant slow-down and shearing are observed upstream of a small pinning point and ice converges at ice-shelf channels. We then combine our flow field with high-resolution elevations from TanDEM-X to infer the Basal Mass Balance (BMB) of the RBIS. This method relies on mass conservation in a Lagrangian frame and enables us to finely detect spatial variability in the BMB. We show that the BMB of the RBIS varies substantially on sub-kilometre scales. Our technique is promising and could easily be applied more widely.Additionally, the flow field is used to investigate how considering/ignoring small pinning points in observations (geometry and velocities) impacts data initialisation of poorly known parameters (e.g. basal friction, ice viscosity) and subsequent ice-sheet modelling with BISICLES. We find that overlooking the pinning point in the bathymetry leads to erroneous ice-shelf properties whereas accurately capturing the pinning point in velocities is of secondary importance. Finally, before concluding the thesis, we discuss the stability of the RBIS and its neighbouring ice shelves. Most studies agree that the ice shelf has remained stable over the last decades to millennia and would likely remain so in the absence of external forcing. We however point out to three potential triggers of instabilities: (i) large quantities of surface meltwater are formed in the grounding zone and subsequently stored on the ice shelf, thereby providing fuel for hydrofracturing; (ii) ice-shelf channels are found to significantly incise the ice inland and (iii) a bathymetric trough beneath the RBIS forms a potential gateway for warm water intrusions the ice-shelf cavity, which could destabilise the ice shelf from below. We close with a short essay on the importance of outreach, where we argue that public engagement as a scientist should be considered as being part of science and should be valued for its worth. This chapter gives us the opportunity to present outreach activities undertaken in the frame of this thesis. We conclude that, just like ice shelves control Antarctic ice losses, science communication determines transfers of scientific expertise to public knowledge.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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Dahlén, Sara. "Injuries and Illnesses in Swedish Para Athletes During the Paralympic Games 2012-2018." Thesis, Gymnastik- och idrottshögskolan, GIH, Institutionen för fysisk aktivitet och hälsa, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:gih:diva-6755.

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Aim: The aim of the study was to analyse the injuries and illnesses in Swedish Para athletes during four Paralympic Games (PG), 2012-2018. The research questions (RQ) were: 1) what was the injury incident rate (IR), and which anatomical areas were affected by injuries? 2) what was the illness IR and which physiological systems were affected by illnesses? 3) did the injury and illness IR differ between the Swedish delegation and the reference group (RG), where most athletes participating in the four PGs were included? 4) were there any associations between injury and illness IR and subgroups of athletes? Method: A retrospective analysis of data from a large ongoing prospective study of injuries and illnesses initiated by the International Paralympic Committee in 2012. Data from 157 Swedish Paralympic athletes were analysed and compared to previous results from the RG.  For RQ1, 2 and 3, injuries and illnesses were reported as IR, calculated per 1000 athlete days, in the Swedish delegations (RQ1-3) and compared to the RG (RQ3). For RQ4, a univariate logistic regression analysis was conducted to find possible associations between risk of injury and illness, and subgroups. Results: The injury IR in Swedish athletes varied between the four PGs, from 2.5 to 59.5 per 1000 athlete days. Most injuries occurred in the upper limb. There was a particularly high occurrence of injuries in Para ice hockey players. The illness IR varied from 3.6 per 1000 athlete days in London (2012), to 39.5 in Sochi (2014). The respiratory tract was most affected by illness, in both Swedish athletes and the RG. Most injuries and illnesses in the Swedish delegation were acute onset, but only a minority led to days lost from training and competition. The Swedish delegation had a lower injury IR per 1000 athlete days compared to the RG in all PGs, except for Pyeongchang (2018), where they had an almost three times higher IR. The illness IR for the Swedish delegation was, compared to the RG, lower in London (2012), the same in Rio (2016) and higher in both Sochi (2014) and Pyeongchang (2018). Participation in the Winter Games was associated with a higher risk for both injury and illness compared to the Summer Games. There was also an increased risk of injury for athletes in a contact sport compared to a non-contact sport. Conclusions: This thesis indicates that there is a need to continue monitoring Para athletes, both during and between competitions, to get more knowledge about injury and illness incidence patterns, as well as preventable risk factors. The latter would be especially important for Para ice hockey. It is yet to see if the awareness of the importance of hygiene measures and physical distancing to reduce spreading of infections, brought on by the Covid-19 pandemic, will affect the occurrence of respiratory tract infections during large sporting events.
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Boereboom, Thierry. "Greenhouse gases investigations in ice from periglacial environments." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209673.

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L’environnement périglaciaire en général et les régions de permafrost en particulier, connus pour être très sensibles au changement climatique actuel, sont le sujet de beaucoup d’études sur les émissions de gaz à effet de serre. En effet, le dégel de ces milieux engendre la mobilisation d’une quantité importante de matière organique, précédemment piégée par le froid, favorisant les émissions de dioxyde de carbone et/ou de méthane. L’objectif premier, du présent travail, est de contribuer à l’étude des gaz enfermés dans certains types de glace de ces régions afin de mieux quantifier leur impact potentiel sur le climat.<p>Dans un premier temps, une analyse multiparamétrique a été menée sur deux coins de glace du nord de la Sibérie dans la cadre d’une collaboration avec l’Alfred Wegener Institut (Allemagne). Cette première approche a révélé que l’analyse conjointe de la cristallographie, de l’orientation des axes optiques, du contenu en gaz total et de la composition en gaz des coins de glace est un outil puissant, complémentaire aux analyses des isotopes stables, pour comprendre les conditions paléo-climatiques qui ont régi la construction des coins de glace. Cette étude soutient également l’hypothèse de variations spatiales importantes de l’origine des masses d’air durant les variations climatiques du Pléistocène.<p>Dans un deuxième temps, une analyse des caractéristiques de la glace annuelle de 4 lacs du nord de la Suède a été réalisée afin d’étudier le rôle de la couverture de glace sur les émissions de gaz à effet de serre. En effet, les lacs de ces régions contribuent fortement aux émissions de méthane durant la période d’eau libre et très peu d’études ont analysé la quantité de méthane emprisonnée dans la glace hivernale et relâchée au printemps. Ce projet nous a amené à établir une nouvelle classification des bulles dans la glace de lac basée sur leur contenu en méthane, leur origine, leur forme et leur densité. Il nous a également permis de montrer que plusieurs facteurs interviennent sur le contenu en gaz dans la couverture de glace :le système hydrologique, la variation de la pression atmosphérique, la variabilité des émissions et potentiellement la proximité des sédiments sont autant de facteurs qui déterminent le contenu en gaz. L’analyse de la composition des gaz a révélé que la composition observée dans la glace est sensiblement différente de celle observée durant les périodes d’eau libre. Nous avons également, pour la première fois, établit un budget des émissions de méthane relâchées par la fonte de la couverture de glace au niveau mondial.<p>Cette étude a été complétée par l’analyse des isotopes 13C des gaz des différents types de bulles de notre classification en collaboration avec l’Université d’Utrecht. Nous avons alors mis en évidence que la couverture de glace influence l’équilibre biogéochimique dans l’eau en favorisant l’oxydation du méthane en dioxyde de carbone.<p><br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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12

Lannuzel, Delphine. "Iron biogeochemistry in the Antartic sea ice environment." Doctoral thesis, Universite Libre de Bruxelles, 2006. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210775.

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13

Docquier, David. "Representing grounding-line dynamics in Antarctic ice-sheet models." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209400.

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Since the mid-20th century, global average temperatures have dramatically risen mostly due to the increasing amount of greenhouse gas emissions in the atmosphere. The effects of this recent global warming are already evident and could be exacerbated in the near future if no real action is taken. Recent ice loss in West Antarctica, monitored by satellite measurements and other techniques, gives cause for concern in such a warming world. A major part of this loss has been driven by warm water masses penetrating underneath the ice shelves in this region. This has led to a flow acceleration of the inland outlet glaciers and a greater discharge of ice to the ocean. The actual resulting contribution of West Antarctica to sea-level rise is estimated to be around 0.2 mm per year between 1992 and 2011, i.e. about one third of the ice-sheet contribution (Antarctica and Greenland), and is expected to increase in the near future.<p><p>In this thesis, we first clearly demonstrate that modeling grounding-line (the boundary between grounded and floating ice) migration depends on both the numerical approach and the physical approximation of the ice-sheet model used. Ice-sheet models prescribing the ice flux at the grounding line and using appropriate physical level and numerical approach converge to the same steady-state grounding-line position irrespective of the grid size used. However, the transient behavior of those models is less accurate than other models and leads to an overestimated grounding-line discharge. Therefore, they need to be used with particular attention on short time scales. Furthermore, the non-inclusion of vertical shear stress in those models increases the effective viscosity and gives steady-state grounding-line positions further downstream when compared to full-Stokes models.<p><p>The second major finding of this thesis is the high control of geometry (glacier width and bedrock topography) on Thwaites Glacier, one of the fastest-flowing outlet glaciers in West Antarctica. A flowline finite-difference Shallow-Shelf Approximation (SSA) model is applied to the glacier and shows that ice-flow convergence (through width parameterization) slows down the grounding-line retreat when compared to simulations where the width is constant. A new buttressing parameterization is also tested on the glacier and permits a better understanding of this effect. Finally, the three-dimensional version of the model above is applied to Thwaites Glacier and highlights the strong control of lateral variations in bedrock topography on grounding-line migration./Depuis le milieu du 20e siècle, les températures moyennes globales ont fortement augmenté principalement à cause de l'augmentation des émissions de gaz à effet de serre d'origine humaine. Les effets de ce réchauffement global récent sont déjà détectables et pourraient s'accentuer dans un futur proche si aucune mesure réelle n'est prise. La perte récente de glace en Antarctique de l'Ouest, enregistrée par mesures satellites et d'autres techniques, est préoccupante dans un monde qui se réchauffe. Une grande partie de cette perte de glace est due à la pénétration de masses d'eau chaude sous les plateformes de glace flottante dans cette région. Cela engendre une accélération de l'écoulement des glaciers émissaires et une plus grande décharge de glace vers l'océan. Ainsi, la contribution récente à la hausse du niveau de la mer de l'Antarctique de l'Ouest s'élève à environ 0.2 mm par an entre 1992 et 2011, c'est-à-dire près du tiers de la contribution des calottes glaciaires (Antarctique et Groenland). On estime que cette contribution va continuer à augmenter dans le futur proche.<p>Dans cette thèse, nous démontrons clairement que la modélisation de la migration de la ligne d'ancrage (frontière entre glaces posée et flottante) dépend de l'approche numérique et de l'approximation physique du modèle cryosphérique utilisé. Les modèles cryosphériques qui prescrivent le flux glaciaire à la ligne d'ancrage et qui utilisent un niveau de physique et une approche numérique appropriés convergent vers la même position d'équilibre de la ligne d'ancrage quelle que soit la taille de maille utilisée. Cependant, le comportement transitoire de ces modèles est moins précis que d'autres modèles et mène à une surestimation du flux à la ligne d'ancrage. Dès lors, ces modèles doivent être utilisés avec précaution sur de courtes périodes de temps. De plus, la non inclusion des contraintes verticales de cisaillement dans ces modèles augmente la viscosité effective et donne des positions d'équilibre de la ligne d'ancrage plus en aval en comparaison avec les modèles « full-Stokes ».<p>La seconde découverte majeure de cette thèse est le contrôle important exercé par la géométrie (largeur du glacier et topographie du lit rocheux) sur Thwaites Glacier, l'un des glaciers émissaires les plus rapides en Antarctique de l'Ouest. Un modèle « Shallow-Shelf Approximation » (SSA) résolvant les différences finies le long d'une ligne d'écoulement est appliqué au glacier et montre que la convergence de l'écoulement glaciaire (au travers de la paramétrisation de la largeur) ralentit le retrait de la ligne d'ancrage comparé aux simulations où la largeur est constante. Une nouvelle paramétrisation de l'effet arc-boutant est testée sur le glacier et permet de mieux comprendre cet effet. Finalement, la version en trois dimensions du modèle ci-dessus est appliquée à Thwaites Glacier et met en évidence le contrôle important des variations latérales de l'altitude du lit rocheux sur la migration de la ligne d'ancrage.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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14

Zanabria, Angulo Victor Jose. "La capacidad estatal en el control del tránsito vehicular en Lima e Ica en los años 2015-2016." Master's thesis, Pontificia Universidad Católica del Perú, 2017. http://tesis.pucp.edu.pe/repositorio/handle/123456789/13249.

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Peruvian society recognizes two major problems that affect citizen insecurity and road insecurity, although these problems are seen daily on the streets, an analysis of what is related with them hasn´t been concluded and because the Peruvian state has no authority to control their factors of existence. This study analyzes the problem about state competition in order to control traffic, understanding that it is a public policy, which as such it looks for a problem about the society and it faces similar problems in the central government as in hobbies. As it´s detailed in this context, the problem is national, however, the capacities are diverse and diffuse, there is no consensus for its improvement and much less exist articulation or coordination in order to strengthen the authority acts and improve state capacities, therefore, this study seeks to analyze the problem determines the limitations of the policy and contribute to its solution<br>Tesis
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15

Bulthuis, Kevin. "Towards robust prediction of the dynamics of the Antarctic ice sheet: Uncertainty quantification of sea-level rise projections and grounding-line retreat with essential ice-sheet models." Doctoral thesis, Universite Libre de Bruxelles, 2020. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/301049.

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Recent progress in the modelling of the dynamics of the Antarctic ice sheet has led to a paradigm shift in the perception of the Antarctic ice sheet in a changing climate. New understanding of the dynamics of the Antarctic ice sheet now suggests that the response of the Antarctic ice sheet to climate change will be driven by instability mechanisms in marine sectors. As concerns have grown about the response of the Antarctic ice sheet in a warming climate, interest has grown simultaneously in predicting with quantified uncertainty the evolution of the Antarctic ice sheet and in clarifying the role played by uncertainties in predicting the response of the Antarctic ice sheet to climate change. Essential ice-sheet models have recently emerged as computationally efficient ice-sheet models for large-scale and long-term simulations of the ice-sheet dynamics and integration into Earth system models. Essential ice-sheet models, such as the fast Elementary Thermomechanical Ice Sheet (f.ETISh) model developed at the Université Libre de Bruxelles, achieve computational tractability by representing essential mechanisms and feedbacks of ice-sheet thermodynamics through reduced-order models and appropriate parameterisations. Given their computational tractability, essential ice-sheet models combined with methods from the field of uncertainty quantification provide opportunities for more comprehensive analyses of the impact of uncertainty in ice-sheet models and for expanding the range of uncertainty quantification methods employed in ice-sheet modelling. The main contributions of this thesis are twofold. On the one hand, we contribute a new assessment and new understanding of the impact of uncertainties on the multicentennial response of the Antarctic ice sheet. On the other hand, we contribute new methods for uncertainty quantification of geometrical characteristics of the spatial response of physics-based computational models, with, as a motivation in glaciology, a focus on predicting with quantified uncertainty the retreat of the grounded region of the Antarctic ice sheet. For the first contribution, we carry out new probabilistic projections of the multicentennial response of the Antarctic ice sheet to climate change using the f.ETISh model. We apply methods from the field of uncertainty quantification to the f.ETISh model to investigate the influence of several sources of uncertainty, namely sources of uncertainty in atmospheric forcing, basal sliding, grounding-line flux parameterisation, calving, sub-shelf melting, ice-shelf rheology, and bedrock relation, on the continental response on the Antarctic ice sheet. We provide new probabilistic projections of the contribution of the Antarctic ice sheet to future sea-level rise; we carry out stochastic sensitivity analysis to determine the most influential sources of uncertainty; and we provide new probabilistic projections of the retreat of the grounded portion of the Antarctic ice sheet. For the second contribution, we propose to address uncertainty quantification of geometrical characteristics of the spatial response of physics-based computational models within the probabilistic context of the random set theory. We contribute to the development of the concept of confidence sets that either contain or are contained within an excursion set of the spatial response with a specified probability level. We propose a new multifidelity quantile-based method for the estimation of such confidence sets and we demonstrate the performance of the proposed method on an application concerned with predicting with quantified uncertainty the retreat of the Antarctic ice sheet. In addition to these two main contributions, we contribute to two additional pieces of research pertaining to the computation of Sobol indices in global sensitivity analysis in small-data settings using the recently introduced probabilistic learning on manifolds (PLoM) and to a multi-model comparison of the projections of the contribution of the Antarctic ice sheet to global mean sea-level rise.<br>Les progrès récents effectués dans la modélisation de la dynamique de la calotte polaire de l'Antarctique ont donné lieu à un changement de paradigme vis-à-vis de la perception de la calotte polaire de l'Antarctique face au changement climatique. Une meilleure compréhension de la dynamique de la calotte polaire de l'Antarctique suggère désormais que la réponse de la calotte polaire de l'Antarctique au changement climatique sera déterminée par des mécanismes d'instabilité dans les régions marines. Tandis qu'un nouvel engouement se porte sur une meilleure compréhension de la réponse de la calotte polaire de l'Antarctique au changement climatique, un intérêt particulier se porte simultanément vers le besoin de quantifier les incertitudes sur l'évolution de la calotte polaire de l'Antarctique ainsi que de clarifier le rôle joué par les incertitudes sur le comportement de la calotte polaire de l'Antarctique en réponse au changement climatique. D'un point de vue numérique, les modèles glaciologiques dits essentiels ont récemment été développés afin de fournir des modèles numériques efficaces en temps de calcul dans le but de réaliser des simulations à grande échelle et sur le long terme de la dynamique des calottes polaires ainsi que dans l'optique de coupler le comportement des calottes polaires avec des modèles globaux du sytème terrestre. L'efficacité en temps de calcul de ces modèles glaciologiques essentiels, tels que le modèle f.ETISh (fast Elementary Thermomechanical Ice Sheet) développé à l'Université Libre de Bruxelles, repose sur une modélisation des mécanismes et des rétroactions essentiels gouvernant la thermodynamique des calottes polaires au travers de modèles d'ordre réduit et de paramétrisations. Vu l'efficacité en temps de calcul des modèles glaciologiques essentiels, l'utilisation de ces modèles en complément des méthodes du domaine de la quantification des incertitudes offrent de nombreuses opportunités afin de mener des analyses plus complètes de l'impact des incertitudes dans les modèles glaciologiques ainsi que de développer de nouvelles méthodes du domaine de la quantification des incertitudes dans le cadre de la modélisation glaciologique. Les contributions de cette thèse sont doubles. D'une part, nous contribuons à une nouvelle estimation et une nouvelle compréhension de l'impact des incertitudes sur la réponse de la calotte polaire de l'Antarctique dans les prochains siècles. D'autre part, nous contribuons au développement de nouvelles méthodes pour la quantification des incertitudes sur les caractéristiques géométriques de la réponse spatiale de modèles physiques numériques avec, comme motivation en glaciologie, un intérêt particulier vers la prédiction sous incertitudes du retrait de la région de la calotte polaire de l'Antarctique en contact avec le lit rocheux. Dans le cadre de la première contribution, nous réalisons de nouvelles projections probabilistes de la réponse de la calotte polaire de l'Antarctique au changement climatique au cours des prochains siècles à l'aide du modèle numérique f.ETISh. Nous appliquons des méthodes du domaine de la quantification des incertitudes au modèle numérique f.ETISh afin d'étudier l'impact de différentes sources d'incertitude sur la réponse continentale de la calotte polaire de l'Antarctique. Les sources d'incertitude étudiées sont relatives au forçage atmosphérique, au glissement basal, à la paramétrisation du flux à la ligne d'ancrage, au vêlage, à la fonte sous les barrières de glace, à la rhéologie des barrières de glace et à la relaxation du lit rocheux. Nous réalisons de nouvelles projections probabilistes de la contribution de la calotte polaire de l'Antarctique à l'augmentation future du niveau des mers; nous réalisons une analyse de sensibilité afin de déterminer les sources d'incertitude les plus influentes; et nous réalisons de nouvelles projections probabilistes du retrait de la région de la calotte polaire de l'Antarctique en contact avec le lit rocheux.Dans le cadre de la seconde contribution, nous étudions la quantification des incertitudes sur les caractéristiques géométriques de la réponse spatiale de modèles physiques numériques dans le cadre de la théorie des ensembles aléatoires. Dans le cadre de la théorie des ensembles aléatoires, nous développons le concept de régions de confiance qui contiennent ou bien sont inclus dans un ensemble d'excursion de la réponse spatiale du modèle numérique avec un niveau donné de probabilité. Afin d'estimer ces régions de confiance, nous proposons de formuler l'estimation de ces régions de confiance dans une famille d'ensembles paramétrés comme un problème d'estimation de quantiles d'une variable aléatoire et nous proposons une nouvelle méthode de type multifidélité pour estimer ces quantiles. Finalement, nous démontrons l'efficacité de cette nouvelle méthode dans le cadre d'une application relative au retrait de la région de la calotte polaire de l'Antarctique en contact avec le lit rocheux. En plus de ces deux contributions principales, nous contribuons à deux travaux de recherche additionnels. D'une part, nous contribuons à un travail de recherche relatif au calcul des indices de Sobol en analyse de sensibilité dans le cadre de petits ensembles de données à l'aide d'une nouvelle méthode d'apprentissage probabiliste sur des variétés géométriques. D'autre part, nous fournissons une comparaison multimodèle de différentes projections de la contribution de la calotte polaire de l'Antarctique à l'augmentation du niveau des mers.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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Callens, Denis. "Impact of improved basal and surface boundary conditions on the mass balance of the Sr Rondane Mountains glacial system, Dronning Maud Land, Antarctica." Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209217.

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Mass changes of polar ice sheets have an important societal impact, because they affect global sea level. Estimating the current mass budget of ice sheets is equivalent to determining the balance between the surface mass gain through precipitation and the outflow across the grounding line. In Antarctica, the latter is mainly governed by oceanic processes and outlet glacier dynamics.<p>In this thesis, we assess the mass balance of a part of eastern DronningMaud Land via an input/output method. Input is given by recent surface accumulation estimations of the whole drainage basin. The outflow at the grounding line is determined from the radar data of a recent airborne survey and satellite-based velocities using a flow model of combined plug flow and simple shear. We estimate the regional mass balance in this area to be between 1.88±8.50 and 3.78±3.32 Gt a−1 depending on the surface mass balance (SMB) dataset used. This study also reveals that the plug flow assumption is acceptable at the grounding line of ice streams.<p>The mass balance of drainage basins is governed by the dynamics of their outlet glaciers and more specifically the flow conditions at the grounding line. Thanks to an airborne radar survey we define the bed properties close to the grounding line of the West Ragnhild Glacier (WRG) in the Sør Rondane Mountains. Geometry and reflectivity analyses reveal that the bed of the last 65 km upstream of the grounding line is sediment covered and saturated with water. This setting promotes the dominance of basal motion leading to a change in the flow regime: in the interior flow is governed by internal deformation while its relative importance decreases to become driven by basal sliding.<p>Subsequently we present the results of the reconstruction of the SMB across an ice rise through radar data and inverse modelling. The analysis demonstrates that atmospheric circulation was stable during the last millennium. Ice rises induce an orographic uplift of the atmospheric flow and therefore influence the pattern of the SMB across them, resulting in an asymmetric SMB distribution. Since the geometry of the internal reflection horizons observed in radar data depends on the SMB pattern, the asymmetry observed in radar layers reveals the trajectories of air masses at the time of deposit. We present an original and robust method to quantify this SMB distribution. Combining shallow and deep radar layers, SMB across Derwael Ice Rise is reconstructed. Two methods are employed as a function of the depth of the layers: i.e. the shallow layer approximation for the surface radar layers and an optimization technique based on an ice flow model for the deeper ones. Both methods produce similar results. We identify a difference in SMB magnitude of 2.5 between the flanks and the ice rise divide, as well as a shift of ≈4 km between the SMB maximum and the crest. Across the ice rise, SMB exhibits a very large variability, ranging from 0.3 to 0.9 mw.e. a−1. This anomaly is robust in time.<p>Finally we draw a comprehensive description of the Sør Rondane Mountains sector. The glacial system is close to the equilibrium and seems stable but evidences suggest that it is a fragile equilibrium. The proximity of the open ocean certainly favours the interaction between warm water and the ice shelf cavity conducting to potential important melting. The thinning associated with this melting can detach the ice shelf from pinning points. This will reduce the buttressing from the ice shelf, outlet glaciers will accelerate and mass transfer toward the ocean will increase. Therefore, the future of Antarctic Ice Sheet directly depends on the changes affecting its boundaries and assessing the sensitivity of the ice sheets is essential to quantify and anticipate the future variation of mass balance.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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17

Brabant, Frédéric. "Physical and biogeochemical controls on the DMS/P/O cycle in Antarctic sea ice." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209587.

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Il a récemment été démontré que la glace de mer antarctique pouvait jouer un rôle significatif dans la dynamique des gaz à effet climatique (dont le dimethylsulfure ou DMS) dans les régions polaires. Ce travail s’est d’abord attaché à la mise au point d’une méthode de mesure fiable du diméthylsulfoxyde (DMSO) dans la glace de mer, supprimant les interférences générées par la production de DMS au sein de l’échantillon en réponse au choc osmotique subi lors de la fonte de l’échantillon de glace. Une procédure de détermination séquentielle du DMS, par broyage à sec, puis du dimethylsulfoniopropionate (DMSP) et du DMSO sur le même échantillon de glace a été développée et utilisée à large échelle dans ce travail. Les données du présent travail ont été acquises dans le cadre de deux programmes d’observation intégrés menés sur la glace de mer antarctique à des saisons différentes mais avec une méthodologie commune :1) choix de sites d’étude homogènes afin de minimiser l’impact de la variabilité spatiale sur l’interprétation des résultats dans une optique d’évolution temporelle et 2) priorité à la caractérisation du cadre physico-chimique (texture, température, salinité, couvert de neige, susceptibilité au drainage des saumures,….) avant toute autre analyse. L’étude menée dans le cadre du programme ISPOL (nov.–dec. 2004) a permis d’observer que la stratification des saumures a un impact positif sur la conversion du DMSP en DMS au sein de la glace mais ralentit les flux de DMS et DMSP vers l’océan. Le couvert de glace est caractérisé à cette période de l’année par une perte nette de DMSP et génère des flux combiné de DMS et DMSP du même ordre de grandeur que les flux de DMS atmosphériques mesurés dans le cadre d’autres études. L’étude menée dans le cadre du programme SIMBA (sept.–oct. 2007) a permis de mettre en évidence l’importance du forçage atmosphérique sur le régime thermique et la dynamique du DMS/P/O dans la glace. Les communautés d’algues de surface produisent de fortes concentrations de DMS/P/O en réponse au stress thermique, osmotique et potentiellement radiatif durant les périodes de refroidissement et la mise en place d’un régime soutenu de drainage des saumures contribue à évacuer périodiquement les hautes concentrations de DMS/P/O produites dans la glace vers l’océan sous-jacent. Le couvert de glace affichant une production nette de DMS/P/O à cette période de l’année génère des flux combinés de DMS et DMSP plus de dix fois supérieurs à ceux observés pour la glace estivale. L’étude menée sur de la glace artificielle a permis de mettre en évidence l’impact des processus physico-chimiques sur la signature en gaz de la glace en croissance constituant un premier pas vers la modélisation des transports de gaz dans la glace de mer et leurs échanges au travers des interfaces glace-océan et glace-atmosphère. <p><p><p>SUMMARY - It has recently been demonstrated that Antarctic sea ice recently demonstrated plays a potentially significant role in the dynamics of climatically significant gases (amongst which dimethylsulphide or DMS) in Polar Regions. This research work has initially focused on the development of a reliable method for the determination of dimethylsulphoxide (DMSO) within sea ice, avoiding interferences generated by DMS production within the sample in response to the osmotic shock caused by melting. A sequential determination procedure of DMS, dimethlsulphoniopropionate (DMSP) and DMSO on the same ice sample has been developed and used on a large amount of samples in the present work. Data presented in this research project have been collected in the framework of two integrated sea ice observation programs focused on Antarctic sea ice at different seasons but following a common approach: 1) choice of homogeneous study sites to minimize the impact of spatial variability on the interpretation of the results in a time series perspective and 2) priority given to the characterization of the physicochemical framework (texture, temperature, salinity, snow cover, susceptibility to brine drainage,…) prior to any other study. The study conducted in the framework of the ISPOL experiment (Nov.–Dec. 2004) demonstrated that stratification of the brine inclusions network positively influenced the conversion of DMSP into DMS but decreased fluxes of DMS and DMSP towards the ocean. The ice cover at that time of the year is characterised by a net DMSP loss and generates combined DMS and DMSP fluxes whose values fall in the range of atmospheric DMS flux from sea ice measured in the frame of other studies. The study conducted in the framework of the SIMBA experiment (sept.–oct. 2007) emphasized the importance of atmospheric thermal forcing on the sea ice thermal regime and DMS/P/O dynamics. The surface community of algae produced elevated levels of DMS/P/O in response to thermal, osmotic and potentially radiative stress during periods of atmospheric cooling while the development of an intense brine drainage regime contributed to periodically release the elevated levels of DMS/P/O produced in the sea ice towards the underlying ocean. The ice cover exhibited at that time of the year a net production of DMS/P/O and produced combined DMS and DMSP fluxes more than ten times higher than those observed for summer sea ice. The study conducted on laboratory prepared growing sea ice emphasised the impact of physicochemical processes on the gas signature of growing sea ice and represents a first step towards modelling gas exchanges within sea ice and across its interfaces with the ocean and the atmosphere.<p><br>Doctorat en Sciences agronomiques et ingénierie biologique<br>info:eu-repo/semantics/nonPublished
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18

Jacques, Caroline. "Methane at the ocean-atmosphere interface, from temperate to polar regions: an isotopic approach." Doctoral thesis, Universite Libre de Bruxelles, 2021. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/325149.

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Given its crucial role in atmospheric chemistry and its global warming potential, methane(CH4) deserves to be accurately budgeted. However, the recent renewed rise in atmosphericCH4 growth rates from 2007 on, after a few years of slow-down, attests that sources are notcompensated anymore by sinks, and calls for a better assessment of the processes contributingto the global CH4 budget. Among natural sources, oceanic emissions are still subject tomany uncertainties, due to the lack of sampling. This is particularly relevant in polar regions,where the role of sea ice on CH4 sea-air fluxes is largely unknown.In an effort to contribute to a better characterisation of CH4 dynamics in oceanic environments,we investigated very contrasted settings during a journey from temperate to polarregions and applied the concentration and stable isotope approach.We start by evaluating the performance of a commercially available in situ CH4 sensor(CONTROS HydroC® CH4 from Kongsberg Contros) in controlled and natural environments,with the hope of using it in the framework of our various field campaigns. Although thissensor has the potential to significantly increase the spatial and temporal resolution comparedto discrete sampling, the long response time prevents from using its measurements as absolutevalues in dynamic natural environments and calls for progress in the field of technologies forcontinuous in situ dissolved CH4 measurements. However, the sensor turns out to be veryuseful during cruises to observe relative changes in dissolved CH4 concentrations and guidethe discrete sampling episodes.Our journey starts in the Scheldt estuary, at the transition between land and sea. Stableisotope analyses reveal that the unusual enrichment of dissolved CH4 in 13C and D in theupper estuary could result from intense microbial oxidation or an unknown source upstream.In the lower part of the estuary, this enriched CH4 mixes with depleted CH4 produced bymethanogenesis in the sediments, before entering the North Sea.In the shallow coastal Wadden Sea, we highlight the dominant contribution of coastal areasto oceanic CH4 emissions. The progressive increase in dissolved CH4 concentrations coincidedwith a 2°C warming of seawater. Submarine groundwater discharge, controlled by thespring-neap tide cycle, and tidal pumping might also have contributed to temporal variationsin dissolved CH4 concentrations and isotopic composition.In the Barents Sea, sailing towards polar latitudes, we find that the fractional sea-ice coverdid not induce a significant change in CH4 concentration nor isotopic composition at theocean-atmosphere interface. Local CH4 seepages at the seafloor might be a relict of gashydrate dissociation after the retreat of the Scandinavian Ice Sheet from the continental shelfafter the Last Glacial Maximum.Trapped in landfast sea ice at Barrow (Arctic) and Cape Evans (Antarctic), we find thatthe processes governing CH4 dynamics in sea ice happen to be dependent on the season andthe regional setting, and can be unravelled thanks to stable isotope analyses. At Barrow,the range of delta-13C values points towards in-ice microbial oxidation of CH4 produced bymethanogenesis in the underlying sediments. At Cape Evans, the much higher delta-13C valuessuggest a hydrothermal origin of CH4 trapped in sea ice and/or aerobic production withinsea ice.The journey ends in the Ross Sea, where the high variability and supersaturation observed indissolved CH4 concentrations, as well as carbon isotope signatures typical of a thermogenicorigin, suggest that gas seepages on the continental shelf might be the main source of CH4 tothe water column.This unique dataset of CH4 concentration and stable isotope composition in seawater, in seaice and in the atmosphere, highlights the spatial and temporal variability of the processesgoverning CH4 dynamics across the various oceanic environments investigated. This thesisprovides an example of how the isotopic approach can be successfully applied to disentanglethe biogeochemical cycle of CH4. To better constrain oceanic emissions, we recommend theimplementation of an extensive monitoring network to measure dissolved CH4 continuously,particularly in shallow coastal regions, which contribute the most. Eventually, further studiesshould focus on the Southern Ocean, which has yet to reveal its secrets with regard to CH4dynamics.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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Wolfram, Jaqueline. ""Ich schreibe, solange ich lebe" : Schreiben über die Shoah - der Holocaustüberlebende und Autor Noah Klieger." Bachelor's thesis, Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6732/.

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Der israelische Autor und Journalist Noah Klieger ist in der deutschsprachigen Forschung zur Holocaustliteratur, in deren Kontext theoretische Konzepte und Interpretationen zahlreicher Autoren (u.a. Ruth Klüger, Primo Levi) dieser Gattung vorliegen, bisher kaum beachtet worden. In der vorliegenden Arbeit steht seine 2010 erschienene Autobiographie „Zwölf Brötchen zum Frühstück“ im Zentrum. Innerhalb der Textanalyse wird der Frage nachgegangen, welche Bedeutung das Schreiben für Klieger hat und inwieweit seine als Reportage angelegte Autobiographie, die den sehr faktenbezogenen und dokumentarischen Stil des Journalisten widerspiegelt, den Rezipienten in der Interpretation lenkt und Authentizität erzeugt. Ausgehend von dieser Fragestellung werden für die Arbeit geführte Interviews mit Noah Klieger (oral history) einbezogen und der Erlebnisbericht „Ich habe den Todesengel überlebt“ von Eva Mozes-Kor, die das Konzept des Erlebnisberichtes mit all seinen Eigenschaften konstant bewahrt, zum Vergleich hinzugezogen. Im Fokus der Arbeit steht die Analyse der Autobiographie Kliegers, wobei auf das Genre Reportage, relevante Stilmittel, zentrale Begrifflichkeiten und Veröffentlichungskontexte sowie auf die Gedächtnistheorie von Maurice Halbwachs eingegangen werden. Abschließend wird die Thematik des Vergebens bei Klieger und Mozes-Kor erörtert. Die Forschungsergebnisse stellen den israelischen Holocaustüberlebenden Noah Klieger als Autor vor und verdeutlichen, dass die innerhalb der Gattung Holocaustliteratur gewählten Darstellungsweisen unterschiedliche Formen von Authentizität evozieren.<br>Israeli author and journalist Noah Klieger has been ignored by German scientists of Holocaust literature though there are many theoretical concepts and interpretations of other writers such as Ruth Klüger and Primo Levi. In this paper we will focus on his autobiography published in 2010 named “Zwölf Brötchen zum Frühstück”. In the text analysis we will discuss what the act of writing means to Klieger and to what extent his autobiography reflects relation to facts, documentary pen and influences recipients. In accordance with this leading question we will integrate interviews with Noah Klieger (oral history) and a report from Eva Mozes-Kor titled “Ich habe den Todesengel überlebt”. This report constantly maintains the characteristics of a report. The centre of attention is the analysis of Noah Klieger’s autobiography, the characteristics of a report, rhetorical devices, defining key terminology, the context of publishing as well as Maurice Halbwach’s memory research theories. Finally, we discuss forgiving based on texts by Klieger and Mozes-Kor is discussed. The results of the research introduce Israeli holocaust survivor Noah Klieger as an author and clarify that within holocaust literature the different forms of expression evoke many different facets of authenticity.
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Turcotte, Benoit. "Steep channel ice and hydrological processes." Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/30079/30079.pdf.

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Cette thèse, à travers une collection de cinq articles scientifiques, décrit et quantifie les processus de glace des cours d’eau à forte pente, donc à lit graveleux. Avant que ce projet de recherche ne soit entrepris, certains de ces processus étaient mal compris ou simplement absents de la littérature scientifique, et ce, alors que les cours d’eau à lit graveleux sont répandus en région froide. Les types de glace qui se forment le long de ces cours d’eau incluent la glace de fond, les seuils de glace, les barrages de glace, les champs de glaçage, les digues de glaçage, les couverts de glace suspendus et les carapaces de glace projetée. Certains processus de débâcle tels que les trains de glace et les embâcles sont également mentionnés dans la thèse, mais ne représentent pas son sujet principal. Cette recherche est le fruit de trois hivers d’observation et d’instrumentation sur le bassin versant de la rivière Montmorency. De manière spécifique, ce ne sont non pas quelques sites, mais plutôt plusieurs cours d’eau, d’un petit ruisseau de tête de bassin versant jusqu’à la rivière Montmorency, qui ont été visités quelque 120 fois, surtout durant la période hivernale. Les données recueillies ont permis de dresser un bilan des liens thermiques, cryologiques (glace) et hydrologiques qui existent entre ces cours d’eau. Ces liens forment ce que l’on appelle le continuum hivernal du bassin versant. Chacun des chapitres de cette thèse représente un ouvrage indépendant qui inclut une introduction, une revue de littérature, une conclusion et une bibliographie. Les quatre premiers articles présentent des sujets qui complémentent les chapitres précédents alors que la description qualitative fait progressivement place à l’analyse quantitative. La somme de ces articles contribue à faire de cette thèse un ouvrage complet sur les processus de glace sur les cours d’eau à forte pente. Le dernier chapitre, ou article, présente un modèle conceptuel des différents couverts et processus de glace observables le long de tout type de chenal sous n’importe quelle intensité hivernale.<br>This thesis, through a collection of five publications, describes and quantifies steep (gravel bed) channel ice processes. Before this research project was undertaken the literature on the topic was largely incomplete and ice processes taking place in gravel bed channels, which represent common cold region fluvial settings, could only be partly explained. Ice features forming along steep channels and described in the thesis include anchor ice accumulations, ice weirs, ice dams, icing fields, icing dikes, suspended ice covers, and spray ice shells. This thesis also approaches river ice breakup processes such as ice runs and ice jams. The findings presented in this work are the result of three winters of field observation and steep channels monitoring. Research sites were visited over 120 times, mostly during the winter period. Ice processes were not only described and monitored at a few sites but at the drainage system scale, from a small headwater channel down to the main river channel. The thermal, cryologic, and hydrological interactions between various steep channels of the Montmorency River watershed were analyzed. These links form what is referred to as the watershed continuum. Each chapter of this thesis is an independent publication that includes an introduction, a literature review, a conclusion, and a list of references. The first four articles present a topic that complements previous chapters. The sum of these chapters forms a comprehensive review of the ice processes taking place in steep channels as the qualitative description progressively evolves into a quantitative analysis. The last chapter (article) presents a global conceptual model on river ice types and processes taking place in any fluvial setting in any climate.
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Van, Der Linden Fanny. "Autumn to spring inorganic carbon processes in pack and landfast sea ice in the Ross Sea, Antarctica." Doctoral thesis, Universite Libre de Bruxelles, 2021. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/321790.

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The Ross Sea, the southernmost sea on Earth, presents several iconic features of polar seas: sites of deep water formation, high summer primary production, floating ice shelves, the annual cycle of advance and retreat of sea ice, polynyas and katabatic winds. Furthermore, sea ice in McMurdo sound (western Ross Sea) is one of the most productive marine environments. However, sea ice inorganic carbon dynamics and related air-ice CO2 fluxes have never been documented in the Ross Sea.Two surveys were carried out in the western Ross Sea to bridge over a critical gap in the current understanding of sea ice: autumn and winter processes. The land-based YROSIAE project was a temporal survey from late winter to summer within landfast sea ice. The ship-based PIPERS project was an unique opportunity to study the early stages of sea ice formation (in polynyas) and more common consolidated pack ice in autumn. Based on these two consistent surveys, this work aims to (i) examine the bulk ice pCO2 dynamics in landfast sea ice from late winter to summer (ii) investigate the seasonal pattern (net source vs net sink) and diurnal pattern of air-ice CO2 fluxes (iii) analyse the depth-dependent physical and biogeochemical processes involved in inorganic carbon dynamics (iv) assess the precipitation of calcium carbonate in autumn and during a full bloom season.CO2 fluxes were measured using the chamber technique in autumn, late winter and spring, over open surface water, frazil ice patch, grey unconsolidated ice and consolidated first-year ice. These new autumn and winter data provide a first step to set up the budget of air-ice CO2 fluxes over the year and evaluate the large-scale influence of these fluxes on the annual uptake of CO2 by ice-covered oceans. Our results confirm that sea ice acts as a CO2 source for the atmosphere during ice growth, with enhanced fluxes reported at the early stages of sea ice formation, and shifts to a sink in spring. In late spring, diel pattern superimposed upon this seasonal pattern and was potentially assigned to either ice skin freeze-thaw cycles or diel changes in net community production. The snowpack plays a complex role in CO2 exchanges and can no longer be considered as an inert reservoir lying at the sea ice surface.The main features of the normalized DIC distribution (DIC35) through the ice column were: (i) a marked depletion at the surface from autumn to spring induced by the CO2 releases to the atmosphere (ii) bubble-driven gas enrichment below or within impermeable layers and (iii) an initial DIC35 enrichment in the bottom layer disappearing in spring when the seasonal peak in biomass occurs. At the bottom of landfast ice, in spring, a particular assemblage of microorganisms, the biofilm, led to a massive biomass build-up counterintuitively associated with nutrients accumulation. This biofilm formation may also promote calcium carbonate precipitation. However, in young pack ice or in cold landfast ice in early spring, limited calcium carbonate precipitation was reported. This suggests that calcium carbonate precipitation is not an ubiquitous process, especially in winter and autumn Antarctic sea ice. Comparison of calcium carbonate precipitation and pCO2 measurements advocates that the calcium carbonate precipitation is rather controlled by pCO2 than temperature.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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Mathot, Sylvie. "Phytoplankton in the marginal ice zone and its contribution to the annual primary production of the Southern Ocean." Doctoral thesis, Universite Libre de Bruxelles, 1993. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212778.

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Ferreira, Luana Rufino. "A cooperação internacional do Instituto de Ciências Matemáticas e de Computação da Universidade de São Paulo (ICMC-USP), de 2010 a 2014." Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/8316.

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Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2016-10-25T10:39:48Z No. of bitstreams: 1 DissLRF.pdf: 1456833 bytes, checksum: cf6504277e65f45c815396434b543328 (MD5)<br>Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-11-08T19:08:55Z (GMT) No. of bitstreams: 1 DissLRF.pdf: 1456833 bytes, checksum: cf6504277e65f45c815396434b543328 (MD5)<br>Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-11-08T19:09:01Z (GMT) No. of bitstreams: 1 DissLRF.pdf: 1456833 bytes, checksum: cf6504277e65f45c815396434b543328 (MD5)<br>Made available in DSpace on 2016-11-08T19:09:08Z (GMT). No. of bitstreams: 1 DissLRF.pdf: 1456833 bytes, checksum: cf6504277e65f45c815396434b543328 (MD5) Previous issue date: 2016-08-11<br>Não recebi financiamento<br>This research had the purpose of conducting a data survey of international cooperation practiced by the Institute of Mathematics and Computer Science of Universidade de São Paulo, in the 2010-2014 period. Were recovered and mapped the data of international cooperation related to the following modalities: scientific production with researchers from foreign institutions; international cooperation agreements and memorandum of understanding (formal agreements); missions of foreign university professors for academic activities at ICMC-USP; missions of ICMC-USP professors for academic activities abroad foreign delegations visits at ICMC-USP (professors or staff); ICMC-USP delegations abroad (professors or staff); ICMC-USP´s undergraduate students in student exchange program; ICMC-USP´s graduate students in exchange abroad; undergraduate students from foreign institutions in exchange at ICMC-USP; graduate students from foreign institutions in exchange at ICMC-USP; foreign students enrolled in undergraduate courses at ICMC-USP (full course);Foreign students enrolled in graduate programs at ICMC-USP (full course);foreign postdocs at ICMC-USP with the purpose of analyzing how was carried out international cooperation in the ICMC. After the inventory of data, parameters were built to supply a future database of various modalities of international cooperation of the institute as a public management tool of international cooperation, in that institute.<br>A presente pesquisa teve por objetivo a realização de um levantamento de dados relativos à cooperação internacional praticada pelo Instituto de Ciências Matemáticas e de Computação da Universidade de São Paulo, no período de 2010 a 2014. Foram resgatados e mapeados dados de cooperação internacional relativos às seguintes modalidades: produção científica com pesquisadores de instituições estrangeiras; convênios e acordos de cooperação internacional (acordos formais); missões de docentes vindos do exterior para atividades acadêmicas no ICMC-USP; missões de docentes do ICMC-USP para o exterior com finalidade acadêmica; visitas de delegações estrangeiras no ICMC-USP (docentes ou não); delegações do ICMC-USP para o exterior (docentes ou não); intercâmbio de alunos de graduação do ICMC-USP no exterior; intercâmbio de alunos de pós-graduação do ICMC-USP no exterior; intercâmbio de alunos de graduação de instituições estrangeiras no ICMC-USP; intercâmbio de alunos de pósgraduação de instituições estrangeiras no ICMC-USP; alunos estrangeiros regularmente matriculados nos cursos de graduação do ICMC-USP (curso completo); alunos estrangeiros regularmente matriculados nos programas de pós-graduação do ICMC-USP (programa completo); pós-doutorandos estrangeiros recebidos no ICMC-USP com o intuito de analisar como foi exercida a cooperação internacional no ICMC. Após o arrolamento dos dados, foram construídos parâmetros para alimentação de futuro banco de dados das distintas modalidades de cooperação internacional do referido instituto como ferramenta de gestão pública da cooperação internacional, neste instituto.
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Rini, Pietro. "Analysis of differential diffusion phenomena in high enthalpy flows, with application to thermal protection material testing in ICP facilities." Doctoral thesis, Universite Libre de Bruxelles, 2006. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210893.

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This thesis presents the derivation of the theory leading to the determination of the governing equations of chemically reacting flows under local thermodynamic equilibrium, which rigorously takes into account effects of elemental (de)mixing. As a result, new transport coefficients appear in the equations allowing a quantitative predictions and helping to gain deeper insight into the physics of chemically reacting flows at and near local equilibrium. These transport coefficients have been computed for both air and carbon dioxide mixtures allowing the application of this theory to both Earth and Mars entry problems in the framework of the methodology for the determination of the catalytic activity of Thermal Protections Systems (TPS) materials.<p>Firstly, we analyze the influence of elemental fraction variations on the computation of thermochemical equilibrium flows for both air and carbon dioxide mixtures. To this end, the equilibrium computations are compared with several chemical regimes to better analyze the influence of chemistry on wall heat flux and to observe the elemental fractions behavior along a stagnation line. The results of several computations are presented to highlight the effects of elemental demixing on the stagnation point heat flux and chemical equilibrium composition for air and carbon dioxide mixtures. Moreover, in the chemical nonequilibrium computations, the characteristic time of chemistry is artificially decreased and in the limit the chemical equilibrium regime, with variable elemental fractions, is achieved. Then, we apply the closed form of the equations governing the behavior of local thermodynamic equilibrium flows, accounting for the variation in local elemental concentrations in a rigorous manner, to simulate heat and mass transfer in CO2/N2 mixtures. This allows for the analysis of the boundary layer near the stagnation point of a hypersonic vehicle entering the true Martian atmosphere. The results obtained using this formulation are compared with those obtained using a previous form of the equations where the diffusive fluxes of elements are computed as a linear combination of the species diffusive fluxes. This not only validates the new formulation but also highlights its advantages with respect to the previous one :by using and analyzing the full set of equilibrium transport coefficients we arrive at a deep understanding of the mass and heat transfer for a CO2/N2 mixture.<p>Secondly, we present and analyze detailed numerical simulations of high-pressure inductively coupled air plasma flows both in the torch and in the test chamber using two different mathematical formulations: an extended chemical non-equilibrium formalism including finite rate chemistry and a form of the equations valid in the limit of local thermodynamic equilibrium and accounting for the demixing of chemical elements. Simulations at various operating pressures indicate that significant demixing of oxygen and nitrogen occurs, regardless of the degree of nonequilibrium in the plasma. As the operating pressure is increased, chemistry becomes increasingly fast and the nonequilibrium results correctly approach the results obtained assuming local thermodynamic equilibrium, supporting the validity of the proposed local equilibrium formulation. A similar analysis is conducted for CO2 plasma flows, showing the importance of elemental diffusion on the plasma behavior in the VKI plasmatron torch.<p>Thirdly, the extension of numerical tools developed at the von Karman Institute, required within the methodology for the determination of catalycity properties for thermal protection system materials, has been completed for CO2 flows. Non equilibrium stagnation line computations have been performed for several outer edge conditions in order to analyze the influence of the chemical models for bulk reactions. Moreover, wall surface reactions have been examined, and the importance of several recombination processes has been discussed. This analysis has revealed the limits of the model currently used, leading to the proposal of an alternative approach for the description of the flow-surface interaction. Finally the effects of outer edge elemental fractions on the heat flux map is analyzed, showing the need to add them to the list of parameters of the methodology currently used to determine catalycity properties of thermal protection materials.<br>Doctorat en sciences appliquées<br>info:eu-repo/semantics/nonPublished
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Hernández, Puma Milagro del Rosario. "Análisis de los impactos socioambientales y la percepción de la población del cambio de uso de suelo de zona agrícola a zona urbana en el desarrollo urbano e inmobiliario del distrito de Ica, Perú: el caso de la hacienda San José, periodo 2003 al 2017." Master's thesis, Pontificia Universidad Católica del Perú, 2018. http://tesis.pucp.edu.pe/repositorio/handle/123456789/13453.

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El presente trabajo de investigación titulado “Análisis de los Impactos Socioambientales y la Percepción de la Población del Cambio de Uso de Suelo de Zona Agrícola a Zona Urbana en el Desarrollo Urbano e Inmobiliario del Distrito de Ica, Perú: El Caso de La Hacienda San José, Periodo 2003 al 2017”, tiene como fin identificar los principales impactos ambientales y sociales asociados al proceso de Cambio de Uso de Suelo de zona agrícola a zona urbana en lo que fue una parte de las parcelas de la hacienda San José ubicada en la ciudad de Ica hasta el año 1968, época en la que se dio el proceso de Reforma Agraria por el presidente Velazco Alvarado y empezaron a hacerse las modificaciones en la distribución territorial. Mediante esta investigación, se busca identificar los principales impactos que implica la predominancia de construcción de viviendas y nuevas urbanizaciones para la creciente población urbana de la ciudad de Ica. También se busca entender de qué manera la población afectada o involucrada en este proceso percibe dichos impactos y la manera en que el Cambio de Uso de Suelo en el área de estudio tiene implicancias sobre el desarrollo territorial y el desarrollo inmobiliario de la ciudad.<br>Tesis
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Samyn, Denis. "Structural and geochimical analysis of basal ice from Taylor Glacier, Antarctica: on role and behaviour of the interstistial fluid phase." Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210968.

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Morales, Cumpa Sharon Luz, Panta Ivette Patricia Perez, and Huasco Devaki Marié Visag. "Percepciones de los Exportadores de Pisco de Lima e Ica respecto a la gestión de Marca Perú durante el período 2017 - 2018." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2019. http://hdl.handle.net/20.500.12404/15819.

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El propósito de la presente investigación se enfoca en describir cuáles son las percepciones de los exportadores de Pisco de Lima e Ica con relación a las acciones de la gestión de la Marca Perú durante el periodo 2017 y 2018. El trabajo inicia con el análisis de la importancia del sector de exportaciones en la economía peruana. A partir de ello, se identifica la evolución que ha presentado el sector pisquero peruano en los últimos años y la serie de problemas que afrontan los productores de Pisco, a pesar del evidente progreso. En segundo lugar, se reconoce que la gestión de marca país ha permitido que la Marca Perú adquiera relevancia en Sudamérica. Ahora bien, se comienza con el análisis del entorno en el que se desarrollan las exportaciones, considerando en este la relevancia de los productos bandera. A partir de ello, nace la iniciativa de conocer cómo se ha implementado la estrategia de marca país en uno de los sectores que involucran la gestión de Marca Perú. Para la aplicación de dicho caso, se ha decidido estudiar a los exportadores de Pisco de Lima e Ica, quienes, en la actualidad, vienen tomando acción para fomentar el consumo de Pisco en el ámbito local y extranjero. En ese campo de acción, se desea conocer la intervención de la gestión de Marca Perú en el sector pisquero desde la percepción de los exportadores. Seguidamente, se han desarrollado los campos teóricos de marca sectorial, marca país, comercio exterior, exportaciones, productos bandera y el Pisco, para la construcción del marco teórico que posibilite el entendimiento del caso estudiado. Posteriormente, se aplicaron los conceptos metodológicos basados en el estudio de caso para el desarrollo del trabajo de campo. Para el trabajo de investigación, se propone un enfoque cualitativo, de acuerdo a las características de la muestra elegida y al objetivo de la investigación. La finalidad del enfoque metodológico fue conocer la percepción que tienen los exportadores de Pisco en función de la gestión implementada por las instituciones del Estado para el posicionamiento de la Marca Perú. Los hallazgos se visualizaron de acuerdo a las variables de identificación, diseñadas para los objetivos de la investigación. Se encontró que, si bien se percibe que las estrategias de gestión de marca país implementadas por las instituciones de Estado permitieron el apoyo a los exportadores en temas de promoción, difusión y desarrollo de mercados del Pisco, a nivel internacional, aún se necesita fortalecer los aspectos de nivel de calidad e innovación en el sector.<br>Tesis
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Philippe, Morgane. "Reconstruction of the density profile, surface mass balance history and vertical strain profile on the divide of the Derwael Ice Rise in coastal Dronning Maud Land, East Antarctica." Doctoral thesis, Universite Libre de Bruxelles, 2007. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/254506.

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Antarctic mass balance is mainly controlled by surface mass balance (SMB, i.e. the net effect of precipitations at the surface of the ice sheet) and ice discharge at its margins, mostly through ice shelves. These floating ice bodies made from ice flowing from the continent to the ocean are buttressed by ice rises (elevation of the sea floor on which ice shelf re-grounds) such as the Derwael Ice Rise (DIR) in Dronning Maud Land (DML). In addition to this role important to consider in the future contribution of Antarctica to sea level rise, ice rises are also “climate dipsticks” helping to reconstruct the climate of the past centuries to millennia at high resolution. Due to their coastal location, they witness the changes happening there more rapidly than inland. Furthermore, their internal stratigraphy forms arches that allow to assess their stability, to date their own formation and therefore, in some cases, to constrain the past extension of the ice sheet at the scale of several millennia. As part of the IceCon project :Constraining ice mass changes in Antarctica, this thesis aimed to drill a 120 m ice core (named IC12 for the IceCon project, 2012) at the divide of the DIR and perform physico-chemical analyses to study its density and its internal annual layering with the aim of reconstructing SMB of the last two centuries. We also recorded a virtual image of the borehole using an optical televiewer (OPTV) to assess the ability of this instrument to reconstruct a density profile and measure vertical strain rates when the logging is repeated in the same borehole after a sufficient period of time (here, 2 years).The results show a general increase in snow accumulation rates (SMB) of 30-40% during the 20th century, particularly marked during the last 20-50 years. SMB variability is governed to a large extent by atmospheric circulation and to a lesser extent by variations in sea ice cover. The vertical velocity profile measured from repeat borehole OPTV was applied to refine SMB correction and the results fall in the error range of the corrections made using a model previously developed to study the DIR’s stability. This thesis also contributed to characterizing the spatial variability of SMB across the DIR by dating internal reflection horizons (IRHs), former surfaces of the DIR buried under subsequent snow layers and detected using radio-echo-sounding, and by measuring the density profile of IC12. SMB is found to be 2.5 times higher on the upwind slope than on the downwind slope due to the orographic effect. This pattern is regularly observed on ice rises in DML and stresses the importance of adopting a sufficient spatial resolution (5 km) in climate models.Finally, the technical developments allowing to rapidly reconstruct a density profile from the OPTV image of a borehole contributed to improving our knowledge of two features of Antarctic ice shelves, namely melt ponds, influencing surface mass balance and subglacial channels, influencing basal mass balance. Specifically, the results show that density is 5 % higher in surface trenches associated with subglacial channels, and that ice below melt ponds can reach the density of bubble-free ice due to melting and refreezing processes, with implications on ice shelf viscosity.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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Verbeke, Véronique. "Concentrations en gaz dans la glace de mer: développements techniques et implications environnementales." Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210942.

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La glace de mer couvre jusqu’à 6% de la surface de notre planète. Autour du continent Antarctique, sa superficie varie entre 3.8 et 19 millions de km² (en février et septembre respectivement). Cette superficie présente des variations interannuelles. En parallèle, une évolution de la superficie de la glace de mer a également pour origine le réchauffement climatique global, très médiatisé à l’heure actuelle. Dans ce contexte, et étant donné le rôle que joue la banquise au sein de l’Océan Austral, des études de l’évolution de la glace de mer sont devenues fondamentales. <p>Ce travail a pour objectif d’étudier les relations complexes qui existent entre les processus chimiques, physiques et biologiques qui se déroulent au sein de la glace de mer. La détermination des propriétés physiques et de la composition chimique des glaces de mer correspond en effet à un pré-requis indispensable à l’étude des cycles géochimiques qui existent dans la banquise.<p>Différentes glaces de mer, naturelles ou artificielles, ont été analysées. Pour ce faire, les caractéristiques spécifiques à ce type de glace font que des méthodes d’analyse de la composition en gaz particulières ont été nécessaires.<p>Nous avons ainsi pu montrer que le contenu et la composition en gaz des différentes glaces analysées dépendent de facteurs physico-chimiques et de facteurs biologiques. L’impact des facteurs physico-chimiques se marque lors de l’incorporation initiale des impuretés dans la glace de mer et via une diffusion "post-génétique" tant que la glace est plus chaude que –5°C. En outre, les organismes photosynthétiques sont à l’origine d’une production d’oxygène et d’une consommation de dioxyde de carbone. La composition en gaz résultante peut donc être sensiblement différente de la composition atmosphérique ou de celle des gaz dissous dans l’eau de mer sous-jacente, en été comme en hiver. Il s’agit par conséquent de sérieusement envisager l’impact potentiel de la glace de mer et des microorganismes qu’elle contient, lors du réchauffement et de la débâcle, sur les échanges entre atmosphère et océan comme sur leurs compositions respectives.<p><br>Doctorat en sciences, Spécialisation géographie<br>info:eu-repo/semantics/nonPublished
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30

Nzokou, Tanekou François. "Ice rupture hydrodynamic modeling." Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/26683/26683.pdf.

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Luna, Rojas Daniela. "Hacia una educación digital: factores que influyen en el proceso de implementación de la competencia TIC en la educación básica regular. El caso del Proyecto Aula Digital en Ica en el 2017 – 2019." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2019. http://hdl.handle.net/20.500.12404/17951.

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El presente diseño de investigación, tiene como propósito identificar los factores determinantes que influyen en el desarrollo del proceso de implementación del uso de las TICs en la educación básica regular. La incorporación de las tecnologías de comunicación e información en el sector educativo proviene de los cambios a lo largo del tiempo en la sociedad y como herramientas a utilizar en el entorno escolar. Se establece así, una exploración al proyecto Aula Digital implementado en escuelas del nivel primario de la UGEL de Pisco, en la región de Ica. Se seleccionó solo esta localidad ya que se encontró, a diferencia de otras Ugeles1, que ha tenido resultados positivos, intermedios y por mejorar, lo que contribuye a indagar sobre los factores que incidieron en esta divergencia. Por el momento, se tiene en cuenta tres supuestos para que se dé una adecuada adopción de la competencia TIC en las escuelas. En primer lugar, se señala el factor de agencia y coordinación entre actores para evaluar la situación de involucramiento y apoyo institucional. El segundo factor, es la existencia de un plan pedagógico en el uso digital que influye en la formación del docente y su liderazgo. El tercer factor, se adentra en el uso de la herramienta TIC en el aula y cómo esto genera nuevos espacios de aprendizaje con contenidos digitales entre el docente y el alumno. Respecto, a la metodología utilizada, se tiene un enfoque cualitativo de estudio de casos por medio de fichas de observación, entrevistas y revisión de fuentes secundarias, Por último, está investigación tendrá como público objetivo a alumnos de tercer grado de primaria, docentes, directores, parte del personal del proyecto y autoridades regionales de la localidad de Pisco, distrito de Ica, en donde el proyecto Aula Digital viene realizándose desde hace más de dos años.
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Palomino, de la Cruz Jeannette Marina. "Convalidación de la declaración de la víctima como prueba anticipada en los delitos contra la libertad sexual cometidos en flagrancia delictiva: Ica 2014-2015." Master's thesis, Universidad Nacional Mayor de San Marcos, 2017. https://hdl.handle.net/20.500.12672/6682.

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Publicación a texto completo no autorizada por el autor<br>El documento digital no refiere asesor<br>Rescata la esencialidad y la importancia que tiene la prueba anticipada en el marco del proceso penal peruano, su evolución, implicancias constitucionales, legales y dogmáticas, requisitos, supuestos de aplicación, procedimiento y efectos. Propone convalidar la declaración de la víctima de abuso sexual como prueba anticipada permitiendo la solución de los delitos contra la libertad sexual cometidos en flagrancia delictiva, sin necesidad de llevarse a cabo una audiencia al haberse practicado con las formalidades de ley.<br>Tesis
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Sanjinés, Chávez Paola Lucia, and Mendoza María Isabel Peña. "La participación de los brokers que influye en las exportaciones indirectas de uva fresca de las pymes en la Región Ica - Perú periodo 2014 – 2018." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/652706.

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La presente investigación se enfocó en analizar la participación de los brokers y su influencia en las exportaciones indirectas de uva fresca de las pymes en la Región Ica en el periodo 2014 – 2018, la investigación fue de un enfoque cuantitativo deductivo correlacional y por las características de este estudio, también se utilizó un enfoque de investigación cualitativa. Para el enfoque cuantitativo se estudiaron 33 pymes utilizando estadística descriptiva, usando el software estadístico SPSS IBM; para el enfoque cualitativo, se utilizó un muestreo no probabilístico por conveniencia, aplicando una entrevista semi-estructurada, usando el programa Atlas ti 8. Los resultados arrojaron que los brokers si han influido en las exportaciones de uva, entendiendo que gracias los mismos se obtienen grandes beneficios, ya que promueven el libre comercio entre países lo cual ocasiona una suma positiva de ganancias económicas.<br>This research focused on analyzing the participation of brokers and their influence on indirect exports of fresh grapes from SMEs in the Ica Region in the period 2014 - 2018, the research was a correlational deductive quantitative approach and due to the characteristics of This study also used a qualitative research approach. For the quantitative approach, 33 SMEs were studied using descriptive statistics, using the SPSS IBM statistical software; For the qualitative approach, a non-probability sampling was used for convenience, applying a semi-structured interview, using the Atlasti 8 program. The results showed that the brokers have had an influence on grape exports, understanding that thanks to them they obtain large benefits, since they promote free trade between countries which causes a positive sum of economic gains.<br>Tesis
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CORREA, Jairo dos Passos. "Proposta de índice de correção de chuva (ICC) aplicável aos projetos de captação e aproveitamento de água pluvial." Universidade Federal do Pará, 2017. http://repositorio.ufpa.br/jspui/handle/2011/9860.

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Submitted by Kelren Mota (kelrenlima@ufpa.br) on 2018-05-16T18:47:46Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_PropostaIndiceCorrecao.pdf: 3922953 bytes, checksum: 4089cec860f9dc66e760b0c00b3c5d0c (MD5)<br>Approved for entry into archive by Kelren Mota (kelrenlima@ufpa.br) on 2018-05-16T18:48:18Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_PropostaIndiceCorrecao.pdf: 3922953 bytes, checksum: 4089cec860f9dc66e760b0c00b3c5d0c (MD5)<br>Made available in DSpace on 2018-05-16T18:48:18Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_PropostaIndiceCorrecao.pdf: 3922953 bytes, checksum: 4089cec860f9dc66e760b0c00b3c5d0c (MD5) Previous issue date: 2017-05-26<br>O estudo avalia dados de precipitação para determinação de índices de correção de chuva (icc) aplicável a projetos de captação e aproveitamento pluvial, com auxílio de testes estatísticos não paramétricos, partindo do pressuposto de que uma parte das lâminas de chuva precipitada é descartada. A análise da série histórica pluviográfica de lâminas de chuva mostrou que Belém apresenta grande potencial para aproveitamento de água de chuva, sendo identificados dois períodos, mais e menos chuvoso, no ano e os resultados apresentaram em média um evento de chuva por dia. Os dados são de janeiro de 2001 a dezembro de 2011, nos quais aproximadamente 38% são utilizados apenas para lavagem do sistema de captação. O teste de Anderson-Darling revelou a não aderência das séries de chuva a uma distribuição normal e segundo o teste Mann-Kendall não houve tendência significativa nas séries avaliadas. Assim, após o cálculo das chuvas efetivamente aproveitáveis, determinação dos icc’s, e aplicação do teste de normalidade e o teste de variância de Kruskal-Wallis, foram propostos três índices de correção de chuva que determinam a lâmina efetivamente aproveitável: o primeiro ao longo do ano (0,78), o segundo no período mais chuvoso (0,79) e um terceiro no período menos chuvoso (0,76).<br>The study measure dada of rainfall to determine a rain correction index (rci) applicable in collection projects and rainwater utilization assisted by statistics tests non-parametric, based on assumption that a water line part of rainfall are discarded. The analyses of pluviographic historical set of water lines show that Belem presents large potential to promote rainwater utilization, two periods were identified during the year: a rainier period and a less rainy period. The results present an average of one rainy event per day, from January 2001 to December 2011, around 38% are utilized only to wash the rain water collection system. The Anderson-Darling test revealed the non-adherence of the rain sets in a normal distribution and according to the Mann-Kendall test there wasn’t significant tendency in the evaluated sets. Therefore, after to calculate the effectively rainwater utilization, determination of the rain correction index (rci), the test application of normality and the Kruskal-Wallis variance test, three corrections index that determine the water line effectively usable were proposed: the first during the year (0.78), the second during the most rainy period (0.79) and the third during the less rainy period (0.76).
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Gülbahar, Yasemin, Mustafa Ilkhan, Selcan Kilis, and Okan Arslan. "Informatics education in Turkey : national ICT curriculum and teacher training at elementary level." Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6451/.

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This article is a summary of the work carried out by the Ministry of Education in Turkey, in terms of the development of a new ICT Curriculum, together with the e-Training of teachers who will play an important role in the forthcoming pilot study. Based on recent literature on the topic, the article starts by introducing the “F@tih Project”, a national project that aims to effectively integrate technology into schools. After assessing teachers’ and students’ ICT competencies, as defined internationally, the review continues with the proposed model for the e-training of teachers. Summarizing the process of development of the new ICT curriculum, researchers underline key points of the curriculum such as dimensions, levels and competencies. Then teachers’ e-training approaches, together with selected tools, are explained in line with the importance and stages of action research that will be used throughout the pilot implementation of the curriculum and e-training process.
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O'Grady, David G. "ICT integration : newly qualified primary teachers in Ireland : classroom and school experiences." Thesis, Sheffield Hallam University, 2007. http://shura.shu.ac.uk/20135/.

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This research explored the school and classroom experiences of thirteen newly qualified primary teachers (NQPTS) in Ireland in relation to Information and Communication Technology. These teachers had access to personal laptop computers as student teachers and participated in the ICT elective module in their final year in college. The research adopted a case study qualitative approach, using semi-structured interviews and observations in the classrooms of the participants. Thirteen in-depth interviews were audio recorded in the participants' schools, transcribed and later analysed using Nvivo. Further evidence was gathered through unstructured and unrecorded conversations with the principals of the schools along with documentary evidence from the NQPTs inspectors' probationary reports. As a result, this thesis examined the issues faced by these young teachers as they attempted to integrate ICT into their daily professional lives. The research further explored the role of the ICT school co-ordinator, the principal teacher, the community, the school inspectorate and the national ICT advisory service and how they supported or hindered the NQPTs in relation to ICT classroom use. The main findings of this study indicated that these thirteen NQPTs: Were striving to integrate and infuse ICT into their daily work; Were satisfied with their pre-service experience of ICT, including the laptop programme; Argued that more time be allocated to ICT classroom management issues during pre-service; Suggested that ICT integration should play a more prominent role during teaching practice; Suggested that teaching practice supervisors be more supportive of the role of ICT; Acknowledged the support of their head teacher and school based ICT coordinator regarding ICT integration; Questioned the lack of support they received from the school inspectorate during their probationary year in relation to ICT; Had very little support from the national ICT advisory service during their probationary year. The thesis concludes with six recommendations, posed as questions, relating to the role of the National Centre for Technology in Education (NCTE, Ireland), the role of the school inspector, in particular during the young teacher's probationary year, the role of the school's ICT policy, the role of the colleges' of education supervisors in Ireland during teaching practice, the value of laptop technology during pre-service and finally what form of ICT in-service is relevant to NQPTs and how these recommendations may support young teachers in future years.
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Benros, Santos Lopes Silvania. "Integrated CFD Model for Nanoparticle Production in Inductively Coupled Plasma Reactor: Implementation and Application." Doctoral thesis, Universite Libre de Bruxelles, 2016. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/230486.

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Nanoparticles represent a very exciting new area of research. Their small size, ranging from several nanometers to tens of nanometers, is responsible for many changes in the structural, thermal, electromagnetic, optical and mechanical properties in comparison with the bulk solid of the same materials. However, promoting the use of such material requires well-controlled synthesis techniques to be developed. Inductively coupled thermal plasma (ICTP) reactors have been shown to offer unique advantages over other synthesis methods. The purpose of this thesis is to develop a numerical model to assist the design of an ICTP reactor for the efficient and controlled production of nanoparticles at industrial scale. The complete model describes the evaporation of the micron-sized precursor particles in the plasma flow and the subsequent formation of the nanoparticles in the quenching reactor. The plasma flow is described by a coupled system of the fluid mechanics equations of continuity, momentum, and energy with the vector potential formulation of Maxwell's equations. The solid particles precursors are treated following a Lagrangian approach, taking into account the vapor production field in the plasma flow. An Eulerian model based on the method of moments with interpolative closure is used to describe the formation of nanoparticles by simultaneous nucleation and growth by condensation and coagulation. The coupled plasma torch, particle evaporation and nanoparticle formation models are implemented in 2D and 3D configurations, using the OpenFoam source code. The results show that the effects of the particle evaporation on the temperature field are substantial, even for low particle mass loading. The associated vapor concentration which enters in the reactor has then a direct influence on the formation of nanoparticles. The effects of the plasma torch parameters and the quenching configuration (quench type, position, injection angle and cooling rate) on the contribution of the different formation mechanisms and on the generated particle's size and distribution are studied in both 2D axi-symmetric and 3D geometries. The quench mechanism strongly affects the temperature and the vapor concentration in the reactor, and consequently has an impact on the final particle size distribution. It is shown that the size of the nanoparticles obtained for different quenching conditions is not only a consequence of the cooling rate but also of the trajectories of the vapor and the generated particles imposed by quenching gas. The results have also demonstrated that the predicted particle are smaller and more sensitive to the modifications of the quenching condition when quenching at high temperature. The sensitivity of the complete model to the physical properties of the vapor (vapor pressure and surface tension) is also investigated, in order to identify their effect on the final particle size. The results obtained provide an insight into the phenomena involved during the production of nanoparticles and enable the improvement of ICTP rectors design and nanoparticles synthesis process.<br>Doctorat en Sciences de l'ingénieur et technologie<br>info:eu-repo/semantics/nonPublished
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Alvarez, Hinostroza Angie Alvarez, Sánchez Víctor Andrés Burga, Moscoso Italo Luis Falcón, and Aliaga Ursula María Velarde. "Calidad en el Sector Supermercados en el Perú, 2014." Master's thesis, Pontificia Universidad Católica del Perú, 2015. http://hdl.handle.net/20.500.12404/14807.

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La finalidad de esta investigación es crear conciencia en los altos ejecutivos de las empresas del sector supermercados sobre la importancia de la implementación de un sistema de administración de la calidad como el ISO o el HACCP, ya que ésta permitirá reducir los costos, mejorar los procesos, optimizar los recursos, mejorar la cultura organizacional, aumentar la satisfacción de los clientes y comprometer a los empleados. Para ello, se aplicó un cuestionario dirigido a los gerentes y jefes de los supermercados en el Perú, basado en el Modelo de Nueve Factores del TQM en la Empresa para conocer y validar las diferencias que existen entre los supermercados que aplican un sistema de administración de la calidad de los que no. El cuestionario dio como resultado diferencias en la aplicación de los nueve factores del modelo propuesto, con énfasis en los factores de Alta Gerencia, Satisfacción al Cliente y Gestión de la Calidad del Proveedor. Finalmente, luego de analizar las respuestas del cuestionario, se pudo determinar que los sistemas de administración de la calidad mayormente utilizados por los supermercados en el Perú son el ISO 9000, el ISO 22000 y el sistema HACCP. Así, es relevante recalcar el valor de una buena implementación y monitoreo de un sistema de administración de la calidad que permita tener un mejor control de los procesos de la empresa impactando positivamente en la satisfacción del cliente.<br>The purpose of this research is to create conscientious in the senior executives of the supermarket sector about how important is to make a correct implementation of a quality management system like ISO or HACCP, because it would reduce their costs, allow continuous improvement of their procedures, optimize resources, enhance their organizational culture, increase their clients satisfaction and engage their employees. To get this, a survey was applied and sent to the managers of the supermarkets in Peru, this survey was based on the Nine Factors Model of TQM in the Company that allows knowing and validating the differences between the supermarkets that apply a quality management system from those that do not. The results indicates that there were differences in the application of the nine factors of the proposed model, with emphasis in the following factors: Senior Management, Client Satisfaction and Supplier Quality Management. Finally, after studying the survey results, it was determined that the quality management systems most used by the supermarkets in Peru are ISO 9000, ISO 22000 and HACCP. This way, is transcendental to stress the importance of a good implementation and monitoring of a quality management system that allows better control of the procedures in the company, having a positive impact in the client satisfaction.<br>Tesis
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Dumont, Isabelle. "Interactions between the microbial network and the organic matter in the Southern Ocean: impacts on the biological carbon pump." Doctoral thesis, Universite Libre de Bruxelles, 2009. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210300.

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<p align="justify">The Southern Ocean (ca. 20% of the world ocean surface) is a key place for the regulation of Earth climate thanks to its capacity to absorb atmospheric carbon dioxide (CO2) by physico-chemical and biological mechanisms. The biological carbon pump is a major pathway of absorption of CO2 through which the CO2 incorporated into autotrophic microorganisms in surface waters is transferred to deep waters. This process is influenced by the extent of the primary production and by the intensity of the remineralization of organic matter along the water column. So, the annual cycle of sea ice, through its in situ production and remineralization processes but also, through the release of microorganisms, organic and inorganic nutrients (in particular iron)into the ocean has an impact on the carbon cycle of the Southern Ocean, notably by promoting the initiation of phytoplanktonic blooms at time of ice melting.</p><p><p align="justify">The present work focussed on the distribution of organic matter (OM) and its interactions with the microbial network (algae, bacteria and protozoa) in sea ice and ocean, with a special attention to the factors which regulate the biological carbon pump of the Southern Ocean. This thesis gathers data collected from a) late winter to summer in the Western Pacific sector, Western Weddell Sea and Bellingshausen Sea during three sea ice cruises ARISE, ISPOL-drifting station and SIMBA-drifting station and b) summer in the Sub-Antarctic and Polar Front Zone during the oceanographic cruise SAZ-Sense.</p><p><p align="justify">The sea ice covers were typical of first-year pack ice with thickness ranging between 0.3 and 1.2 m, and composed of granular and columnar ice. Sea ice temperature ranging between -8.9°C and -0.4°C, brines volume ranging between 2.9 to 28.2% and brines salinity from 10 to >100 were observed. These extreme physicochemical factors experienced by the microorganisms trapped into the semi-solid sea ice matrix therefore constitute an extreme change as compared to the open ocean. Sea ice algae were mainly composed of diatoms but autotrophic flagellates (such as dinoflagellates or Phaeocystis sp.) were also typically found in surface ice layers. Maximal algal biomass was usually observed in the bottom ice layers except during SIMBA where the maxima was localised in the top ice layers likely because of the snow and ice thickness which limit the light available in the ice cover. During early spring, the algal growth was controlled by the space availability (i.e. brine volume) while in spring/summer (ISPOL, SIMBA) the major nutrients availability inside sea ice may have controlled algal growth. At all seasons, high concentrations of dissolved and particulate organic matter were measured in sea ice as compared to the water column. Dissolved monomers (saccharides and amino acids) were accumulated in sea ice, in particular in winter. During spring and summer, polysaccharides constitute the main fraction of the dissolved saccharides pool. High concentrations of transparent exopolymeric particles (TEP), mainly constituted with saccharides, were present and their gel properties greatly influence the internal habitat of sea ice, by retaining the nutrients and by preventing the protozoa grazing pressure, inducing therefore an algal accumulation. The composition as well as the vertical distribution of OM in sea ice was linked to sea ice algae.</p><p><p align="justify">Besides, the distribution of microorganisms and organic compounds in the sea ice was also greatly influenced by the thermodynamics of the sea ice cover, as evidenced during a melting period for ISPOL and during a floodfreeze cycle for SIMBA. The bacteria distribution in the sea ice was not correlated with those of algae and organic matter. Indeed, the utilization of the accumulated organic matter by bacteria seemed to be limited by an external factor such as temperature, salinity or toxins rather than by the nature of the organic substrates, which are partly composed of labile monomeric saccharides. Thus the disconnection of the microbial loop leading to the OM accumulation was highlighted in sea ice.</p><p><p align="justify">In addition the biofilm formed by TEP was also involved in the retention of cells and other compounds(DOM, POM, and inorganic nutrients such as phosphate and iron) to the brine channels walls and thus in the timing of release of ice constituents when ice melts. The sequence of release in marginal ice zone, as studied in a microcosm experiments realized in controlled and trace-metal clean conditions, was likely favourable to the development of blooms in the marginal ice zone. Moreover microorganisms derived from sea ice (mainly <10 µm) seems able to thrive and grow in the water column as also the supply of organic nutrients and Fe seems to benefit to the pelagic microbial community.</p><p><p align="justify">Finally, the influence of the remineralization of organic matter by heterotrophic bacterioplankton on carbon export and biological carbon pump efficiency was investigated in the epipelagic (0-100 m) and mesopelagic(100-700 m) zones during the summer in the sub-Antarctic and Polar Front zones (SAZ and PFZ) of the Australian sector (Southern Ocean). Opposite to sea ice, bacterial biomass and activities followed Chl a and organic matter distributions. Bacterial abundance, biomass and activities drastically decreased below depths of 100-200 m. Nevertheless, depth-integrated rates through the thickness of the different water masses showed that the mesopelagic contribution of bacteria represents a non-negligible fraction, in particular in a diatom-dominated system./</p><p><br><p><p align="justify">L’océan Antarctique (± 20% de la surface totale des océans) est un endroit essentiel pour la régulation du climat de notre planète grâce à sa capacité d’absorber le dioxyde de carbone (CO2) atmosphérique par des mécanismes physico-chimique et biologique. La pompe biologique à carbone est un processus majeur de fixation de CO2 par les organismes autotrophes à la surface de l’océan et de transfert de carbone organique vers le fond de l’océan. Ce processus est influencé par l’importance de la production primaire ainsi que par l’intensité de la reminéralisation de la matière organique dans la colonne d’eau. Ainsi, le cycle annuel de la glace via sa production/reminéralisation in situ mais aussi via l’ensemencement de l’océan avec des microorganismes et des nutriments organiques et inorganiques (en particulier le fer) a un impact sur le cycle du carbone dans l’Océan Antarctique, notamment en favorisant l’initiation d’efflorescences phytoplanctoniques dans la zone marginale de glace.</p><p><p align="justify">Plus précisément, nous avons étudié les interactions entre le réseau microbien (algues, bactéries et protozoaires) et la matière organique dans le but d’évaluer leurs impacts potentiels sur la pompe biologique de carbone dans l’Océan Austral. Deux écosystèmes différents ont été étudiés :la glace de mer et le milieu océanique grâce à des échantillons prélevés lors des campagnes de glace ARISE, ISPOL et SIMBA et lors de la campagne océanographique SAZ-Sense, couvrant une période allant de la fin de l’hiver à l’été.</p><p><p align="justify">La glace de mer est un environnement très particulier dans lequel les microorganismes planctoniques se trouvent piégés lors de la formation de la banquise et dans lesquels ils subissent des conditions extrêmes de température et de salinité, notamment. Les banquises en océan ouvert étudiées (0,3 à 1,2 m d’épaisseur, températures de -8.9°C à -0.4°C, volumes relatifs de saumure de 2.9 à 28.2% et salinités de saumures entre 10 et jusque >100) étaient composées de glace columnaire et granulaire. Les algues de glace étaient principalement des diatomées mais des flagellés autotrophes (tels que des dinoflagellés ou Phaeocystis sp.) ont été typiquement observés dans les couches de glace de surface. Les biomasses algales maximales se trouvaient généralement dans la couche de glace de fond sauf à SIMBA où les maxima se trouvaient en surface, probablement en raison de l’épaisseur des couches de neige et de glace, limitant la lumière disponible dans la colonne de glace. Au début du printemps, la croissance algale était contrôlée par l’espace disponible (càd le volume des saumures) tandis qu’au printemps/été, la disponibilité en nutriments majeurs a pu la contrôler. A toutes les saisons, des concentrations élevées en matière organique (MO) dissoute et particulaire on été mesurées dans la glace de mer par rapport à l’océan. Des monomères dissous (sucres et acides aminés) étaient accumulés dans la glace, surtout en hiver. Au printemps et été, les polysaccharides dissous dominaient le réservoir de sucres. La MO était présente sous forme de TEP qui par leurs propriétés de gel modifie l’habitat interne de la glace. Ce biofilm retient les nutriments et gêne le mouvement des microorganismes. La composition et la distribution de la MO dans la glace étaient en partie reliées aux algues de glace. De plus, la thermodynamique de la couverture de glace peut contrôler la distribution des microorganismes et de la MO, comme observé lors de la fonte de la glace à ISPOL et lors du refroidissement de la banquise à SIMBA. La distribution des bactéries n’est pas corrélée avec celle des algues et de la MO dans la glace. En effet, la consommation de la MO par les bactéries semble être limitée non pas par la nature chimique des substrats mais par un facteur extérieur affectant le métabolisme bactérien tel que la température, la salinité ou une toxine. Le dysfonctionnement de la boucle microbienne menant à l’accumulation de la MO dans la glace a donc été mis en évidence dans nos échantillons.</p><p><p align="justify">De plus, le biofilm formé par les TEP est aussi impliquée dans l’attachement des cellules et autres composés aux parois des canaux de saumure et donc dans la séquence de largage lors de la fonte. Cette séquence semble propice au développement d’efflorescences phytoplanctoniques dans la zone marginale de glace. Les microorganismes originaires de la glace (surtout ceux de taille < 10 μm) semblent capables de croître dans la colonne d’eau et l’apport en nutriments organiques et inorganiques apparaît favorable à la croissance des microorganismes pélagiques.</p><p><p align="justify">Enfin, l’influence des activités hétérotrophes sur l’export de carbone et l’efficacité de la pompe biologique à carbone a été évaluée dans la couche de surface (0-100 m) et mésopélagique (100-700 m) de l’océan. Au contraire de la glace, les biomasses et activités bactériennes suivaient les distributions de la chlorophyll a et de la MO. Elles diminuent fortement en dessous de 100-200 m, néanmoins les valeurs intégrées sur la hauteur de la colonne d’eau indiquent que la reminéralisation de la MO par les bactéries dans la zone mésopélagique est loin d’être négligeable, spécialement dans une région dominée par les diatomées.</p><br>Doctorat en Sciences agronomiques et ingénierie biologique<br>info:eu-repo/semantics/nonPublished
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40

Richard, Martin. "Field investigation of freshwater frazil ice dynamics." Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/27986/27986.pdf.

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Malgré la connaissance limitée qu’on a du frasil, il est probablement le plus important acteur pour les cours d’eau en régions froides dans lesquels la glace se forme. Le frasil est aussi une menace réelle et importante pour les structures hydrauliques et donc, un problème pour les ingénieurs. Des mesures quantitatives du frasil sont vitales afin de mieux comprendre sa dynamique, mais très peu d’études ont porté sur le frasil dans son milieu naturel étant données toutes les difficultés techniques qui y sont associées. Celles-ci sont principalement liées à la grande difficulté de détecter le frasil en rivière. Les cristaux sont très sensibles, ils ne peuvent être maniés et ils évoluent et se transforment rapidement. Cette thèse s’adresse au grand besoin en données de terrain et aussi à améliorer la connaissance sur les interactions entre le frasil, l’hydraulique, l’atmosphère et les autres types de glaces rencontrés en rivière. De nombreuses campagnes d’instrumentation en terrain ont été entreprises et une méthodologie permettant la détection et la mesure du frasil en rivière a été développée. Il a été démontré que les profileurs acoustiques sont très efficaces pour ce faire. À partir de données récoltées durant trois hivers, la quantification du frasil est tentée par trois méthodologies différentes et indépendantes. La théorie de Rouse est appliquée aux profils verticaux de retours acoustiques afin d’estimer un diamètre dominant pour la population de particules de glace détectées. Les théories d’inversion de fréquences, appliquées à plus d’une fréquence à la fois, sont utilisées afin d’estimer les dimensions dominantes et des concentrations de frasil en suspension. Finalement, des approches théoriques et des modèles de transfert de chaleur sont utilisés pour prédire la formation et la croissance du frasil. Les résultats de ces modèles sont comparés avec les mesures. Cette thèse montre que les mesures acoustiques sont très prometteuses afin d’obtenir l’information de base sur le frasil qui n’était pas disponible jusqu’à maintenant. De telles données sont aussi très utiles afin de mieux comprendre comment le frasil est produit en rivière, comment il évolue et comment il interagit avec l’eau et l’atmosphère.<br>Despite knowing extremely little about it, frazil ice is the most important building block for ice infested waters from which, and upon which, most ice is subsequently formed. Frazil ice is a major engineering threat to river and marine infrastructure. Quantitative measurements of frazil ice are vital to clarifying its dynamics, but very few studies have assessed frazil ice in natural water bodies. This is mainly because detection of frazil ice in the field is very difficult. The ice is sensitive to handling and evolves and transforms rapidly. This thesis addresses the need for field data and also seeks to understand more about frazil ice interactions with hydraulics, the atmosphere and other ice types encountered in rivers. An efficient methodology to detect frazil ice in rivers was developed and tested through multiple field instrumentation campaigns. From field data that were obtained during three winters, quantification of frazil ice was attempted by different independent methodologies. The Rouse theory was applied to vertical acoustic backscatter measurements in order to estimate frazil ice particles’ dominant size. Multi-frequency inversion methods were used and applied to estimate both dominant size and concentration of suspended frazil ice. Theoretical approaches that use heat flux modelling were used to predict frazil ice growth rates. Those modelled values were compared with acoustic measurements. The thesis shows that acoustic measurements are very promising to get basic information about frazil that has not been available until now. Such data are also very useful to gain a better understanding of how frazil ice is produced, under which conditions it evolves and how it interacts with the water and the atmosphere.
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41

Parise, Cláudia Klose. "Sensitivity and memory of the current mean climate to increased Antarctic sea ice: The role of sea ice dynamics." Instituto Nacional de Pesquisas Espaciais (INPE), 2014. http://urlib.net/sid.inpe.br/plutao/2014/11.19.18.13.

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Esta tese estuda a sensibilidade e memória do clima global ao aumento do gelo marinho Antártico, levando em consideração o tempo de persistência dos máximos de gelo (concentração e espessura) sob condições climáticas atuais. A sensibilidade das \emph{storm tracks} no Hemisfério Sul e do clima da América do Sul ao aumento do gelo marinho também são analisadas, bem como o mecanismo envolvido na restauração do equilíbrio climático. Dois grupos de experimentos foram realizados. No primeiro o gelo marinho é simulado por um modelo de única camada que desconsidera a reologia do gelo, impedindo que o gelo mova quando espesso. No segundo, o gelo marinho é simulado por um modelo multi-camadas que resolve explicitamente a dinâmica do gelo. Cada clima é perturbado com um extremo de condições positivas (\emph{Max}) e climatológicas (\emph{ctl}) de concentração e espessura de gelo marinho Antártico em um conjunto de 30-membros integrados por 10 anos cada. Alterações nas \emph{storm tracks} são analisadas através de um método automatizado de identificação e rastreio de ciclones extratropicais com base em vorticidade relativa. Os resultados mostram que um extremo de gelo marinho Antártico é capaz de persistir $\sim$4-anos sob condições climáticas atuais. Nos 4 anos seguintes o gelo marinho nos experimentos \emph{Max} é semelhante àquele dos experimentos \emph{ctl} e nos últimos 2-anos as diferenças (\emph{max- ctl}) de gelo marinho são negativas. A persistência dos máximos de gelo marinho varia setorialmente e em função do tipo de modelo de gelo. A presença de máximos de gelo marinho Antártico reduz a temperatura do ar dos baixos aos médios níveis da troposfera. O resfriamento das altas latitudes aumenta o transporte de calor para sul e a convergência em baixos níveis. A pressão média ao nível do mar é reduzida (aumentada) sobre as altas (médias) latitudes, padrão típico da fase positiva do Modo Anular Sul. O fluxo de calor sensível do oceano para a atmosfera é intenso nas margens do gelo marinho, onde a baroclinia da atmosfera também aumenta. Os ventos de oeste se intensificam ao sul de $50^{0}$S e se enfraquecem entre $45^{0}$S e $10^{0}$S. A corrente de jato polar se intensifica em direção aos pólos enquanto o jato subtropical se enfraquece em direção ao equador. Em resposta ao fortalecimento do jato polar, a densidade de trajetóricas dos ciclones, ciclogênese e ciclólise aumenta sobre as altas (médias) latitudes. Com o deslocamento das tempestades para sul, a atividade dos distúrbios transientes é reduzida sobre a América do Sul, bem como a formação de ciclones sobre as duas principais regiões ciclogenéticas (em $30^{0}$S e $45^{0}$S). O enfraquecimento do jato subtropical contribui para aumentar a estabilidade estática da atmosfera e reduzir a taxa de precipitação sobre a América do Sul. Os fortes ventos de oeste fortalecem a Corrente Circumpolar Antártica e, conseqüentemente, a deriva de Ekman para o norte. O derretimento do máximo de gelo marinho gera uma entrada da água fria e pouco salina na camada de mistura do Oceano Austral. A medida que essa água superficial flui para o norte há ressurgência da água mais quente e salina (observada abaixo da camada de mistura do oceano) na Divergência Antártica ($60^{0}$S). A memória climática ($\sim$8-anos) armazenada nas camadas superiores do oceano modula a intensidade e duração da resposta atmosférica ao máximo de gelo marinho.<br>This thesis explores the sensitivity and memory of the global climate to increased Antarctic sea ice, taking into account the persistence of sea ice maxima (in concentration and thickness) under current climate conditions. Moreover, the sensitivity of the Southern Hemisphere storm tracks and the South America climate to increasedAntartictic sea ice are also studied as well as the mechanisms involved in restoring the climate balance. In order to isolate the impacts of sea ice dynamics, two sets of sensitivity experiments are performed with the GFDL CM2.1 coupled climate model. In the first set the sea ice is simulated by a simple slab sea ice model which neglects the sea ice dynamics whereas in the second the sea ice is simulated by a sophisticated multi-layer model. The current climate is perturbed with maximum conditions of Antarctic sea ice (max) and compared to the respective control simulation (ctl). The four numerical experiments are integrated for 10 years each in a large 30-member ensemble. The changes to the Southern Hemisphere extratropical cyclones are analysed through an automated of cyclone identification and tracking based on relative vorticity. The impact of increased Antarctic sea ice on the South America climate is analysed through changes in the precipitation regime and the associated atmospheric systems. The results show that a maximum condition of Antarctic sea ice is able to persist $\sim$4-years under current climate conditions.In the following 4-years of model integration the sea ice in the max experiments is similar to that of the ctl experiments and in the last 2-years the (max-ctl) sea ice differences are negative. However, the persistence of Antarctic sea ice maxima varies sectorally and according to the sea ice model type. The Antarctic sea ice maxima reduce the air temperature from the low to mid-levels. This increases the poleward meridional temperature gradient, resulting in air ascending over the high-latitudes.The mean sea level pressure is reduced (increased) over the high (mid)-latitudes, a typical pattern of the Southern Annular Mode positive phase. The sensible heat flux from the ocean to the atmosphere is intensified at the sea ice edges increasing the atmospheric baroclinicity there. The westerly winds are intensified south of 50$^{°}$S and weakened from 45$^{°}$S to 10$^{°}$S. The polar jet stream intensifies poleward whereas the subtropical jet stream weakens toward the Equator. In response to the polar jet strengthening, the cyclone track density, cyclogenesis and cyclolysis have increased (decreased) over the high (mid)-latitudes. The eddy activity is reduced over South America as well as the cyclogenesis over the two main regions (at 30$^{°}$S and 45$^{°}$S ). The weaker subtropical jet contributes to enhanced atmospheric static stability and reduces the precipitation rate over South America. The stronger westerlies strengthen the Antarctic Circumpolar Current and, consequently, the Ekman drift northward. The melting of the sea maximum generates an imput of cold and fresh melt water into the ocean mixed-layer of the Southern Ocean (from the surface to 100 m ). As this surface water flows northward there is upwelling of the warmer and saltier water (observes below the ocean mixed-layer) on the Antarctic Divergence (60$^{°}$S). The climate memory stored in the upper ocean layers ($\sim$8-years) modulates the intensity and timing of the atmospheric response.
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42

Norman, Philip. "Optimisation of the inductively-coupled plasma for the analysis of solutions and slurries." Thesis, University of Plymouth, 1987. http://hdl.handle.net/10026.1/2073.

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The application of inductively-coupled plasma (ICP) spectrometry for the analysis of solutions and slurries is reviewed. The critical parameters which affect analytical performance are identified and methods for the optimisation of the ICP for such applications demonstrated. Particle size of the suspended sample is shown to be the most important factor in the analysis of slurry samples. It is demonstrated that only particles less than 8 um in diameter reach the plasma even when the maximal diameter injector tube (3 mm i.d.) is used. Accordingly various methods for the reduction of particle size have been investigated and milling shown to be the preferable approach. A low cost method using blown zirconia spheres in a screw-cap plastic bottle agitated on a flask shaker was developed. Using this method it proved possible to analyse a wide variety of solid samples using slurry atomisation using both ICP- atomic emission spectrometry (ICP-AES) and ICP-mass spectrometry (ICP-MS) with aqueous calibration. Results are presented for the elemental analysis of certified reference material (CRM) soils, catalyst samples, a zeolite, titanium dioxide, P.T.F.E. powder, and unfiltered natural waters by slurry atomisation ICP-AES. Comparison by other techniques showed excellent accuracy for major, minor and trace elements and equivalent precision to solution analysis. The CRM soils, catalysts and the zeolite were also analysed by ICP-MS using slurry atomisation with similar success and enhanced accuracy at the trace level. Aluminium proved to be an exception and generally low recoveries (80-90%) were observed for this element using slurry atomisation. Finally the uses of the simplex optimisation algorithm to improve analytical performance, particularly in ICP-AES, is discussed. A computer program to facilitate the use of simplex optimisation for a variety of instrumentation was written and its use in three different analytical techniques demonstrated. The necessary hardware and software modifications to a commercially available ICP spectrometer to enable automated simplex optimisation are described. The prospects for such intelligent self-optimising instrumentation are discussed as is the potential extension of the application of slurry analysis by ICP-AES and ICP-MS.
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43

Nyberg, Sandra, and Sandra Gebara. "Ishockey-VM 2013 : En studie baserad på världsmästerskap inom ishockey och dess marknadsföring." Thesis, Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-24394.

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44

Skálová, Barbora. "MICE CESTOVNÍ RUCH V PRAZE SE ZAMĚŘENÍM NA POŘÁDÁNÍ KONGRESU ICCA 2017." Master's thesis, Vysoká škola ekonomická v Praze, 2016. http://www.nusl.cz/ntk/nusl-262207.

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This thesis deals with the topic of congress tourism, which is perceived as a substantially attractive form of tourism in many destinations. The practical part focuses on the annual congress organized by ICCA - a significant international conference association, that Prague will host in 2017. The aim of this work is to characterize the sector of convention industry with emphasis on the segment of congresses and conferences organized by associations and other non-profit organizations, and subsequently to evaluate the steps the entities participating in preparation and execution of the ICCA prestigious congress have taken so far.
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45

Dong, Na. "Border ice processes on the Saint Lawrence River." Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/28450/28450.pdf.

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Border ice is one of many ice freeze-up processes, but it is discussed only to a limited extent in the literature. Border ice formation can be a precursor for ice jam formation that may restrict navigation and lead to flooding. This master’s thesis is mainly devoted to the research on the border ice on the Saint Lawrence River from Montréal to Québec City. This reach stays artificially open all winter because commercial ships are continuously preventing a full ice cover to form. The traffic also limits the extent of border ice. This study provides key information on ice formation and decay. Through analysis of Environment Canada’s historical data (ice charts from 2004 to 2009), the areal coverage of border ice is analyzed during freeze-up, winter and breakup periods. The historical information of ice coverage is collected in order to find out the factors which influence its formation and its spatial limits. Border ice growth and decay rates are also discussed. The thesis shows that border ice coverage has three stages including the rapid growth period at the beginning of the winter, the relatively stable period in the mid-winter and the breakup period as March progresses. During the mid-winter period, the border ice coverage sometimes drops sharply if the air temperature rises above 0 °C and/or if there is some rain. It was also found that the maximum border ice spatial limits are quite similar over the five winter seasons. Based on the analysis of the ice charts, a number of empirical laws regarding the formation and decay of border ice are proposed. Along the river flowing direction, the border ice is formed easily when there are obstacles particularly at the downstream end. The obstacles could include river bends, ice booms, shoals, artificial islands, bridge piers and so on. Thus, the obstacle influences the flow velocity, which is an important factor for ice formation and also provides an object against which the ice can become fast and initiate its formation. On average, border ice reaches 20% of its maximum coverage when the accumulated freezing degree days (AFDD) reaches 124 °C-D. This is followed by a rapid growth period that ends when the ice cover reaches about 80% of its maximum cover corresponding to AFDD equal to 247 °C-D. Border ice coverage usually reaches the maximum value when the average AFDD is 551 °C-D corresponding to the end of January. The winter period is characterised by a stable ice cover (>90% of max) upstream of Trois-Rivières except in the event of a mid-winter thaw. Downstream of Trois-Rivières there is no stable period as the decay begins very soon after the ice reaches its maximum value. Breakup is a gradual process that normally begins on about Feb. 15th downstream of Trois- Rivières and about March 1st upstream. Most ice has normally gone by March 31st. Moreover, the river flow velocity, river depth and Froude number along the limits of border ice once it reaches its maximal areal coverage are evaluated and analyzed. The flow velocity is almost always less than 1.0 m/s; the maximum Froude number is normally 0.1 at Lake Saint-Pierre and 0.2 in the Montréal to Sorel reach; river depth at the ice edge can vary widely. Through numerical modelling, it was found that border ice increased the current velocity by 0.1 m/s in the Lake Saint-Pierre reach and raised water levels by 14 cm in the Montréal to Sorel reach.<br>La glace de rive est un des nombreux processus de formation des couverts de glace sur les rivières. Cependant peu d’articles dans la littérature traitent de ce sujet malgré que la formation de la glace de rive peut-être un précurseur de l’apparition d’embâcles qui peuvent entrainer des inondations. Ce mémoire de Maitrise porte sur l’étude de la glace de rive le long de la portion du fleuve Saint-Laurent allant de Montréal à Québec. Du fait qu’il y a de la navigation commerciale toute l’année, le fleuve reste ouvert (libre d’un couvert de glace entier) artificiellement pendant tout l’hiver. Ce trafic limite aussi l’extension de la glace de rive. Cette étude fournit des informations clés sur la formation et la désagrégation de la glace de rive. À partir des données historiques d’Environnement Canada (cartes des glaces de 2004 à 2009), la répartition superficielle de la glace de rive est analysée pour les périodes de formation, de stabilité et de rupture de la glace. Les informations historiques sur les couvertures de glace sont collectées afin de déterminer les paramètres qui influencent la formation et les limites spatiales de ce type de glace. Les taux de croissance et de décomposition de la glace de rive sont aussi abordés. Il est montré que l’évolution de la structure propre à la couverture de la glace de rive se fait en trois étapes. Une période de formation rapide (début hiver), suivie d’une période stable (milieu d’hiver) et enfin une période de rupture (pendant le moi de mars). Pendant la période stable, la glace de rive se rompt partiellement parfois lorsque la température de l’air monte au dessus de zéro °C et surtout lorsque le redoux est accompagné de pluie. Il a été trouvé aussi que les limites spatiales maximales des glaces de rive sont très semblables sur 5 hivers de la période d’étude. À partir de l’analyse des cartes des glaces, un certain nombre de relations empiriques sont proposées. Ces relations caractérisent la formation et la désagrégation des glaces de rive. Le long de la direction de l’écoulement la glace de rive est formée facilement en présence d’obstacles, et particulièrement lorsqu’elles sont à l’extrémité aval. Parmi ces obstacles on peut citer les méandres de rivière, les bancs, les estacades, les iles artificielles, les piliers de ponts. Ainsi, les obstacles influencent la vitesse d’écoulement qui est un paramètre important dans la formation de la glace et peut aussi effectuer un apport d’objets sur lesquels la glace peut s’attacher et initier son accroissement. En moyenne la glace de rive atteint 20% de sa couverture maximale lorsque son le nombre de degrés jours accumulés (DJA) atteint 124 °C-j. Ceci est suivi d’une période d’accroissement rapide qui prend fin lorsque la couverture de glace atteint 80% de son maximum qui correspond à un DJA de 247 °C-j. La couverture de glace de rive atteint son maximum lorsque le DJA atteint 551 °C-j; ce qui correspond normalement à la période de fin janvier. La période d’hiver est caractérisée par une couverture de glace stable (supérieure à 90% de son maximum) en amont de Trois-Rivières, sauf pendant les périodes de dégel mi hivernales. À l’aval de Trois-Rivières, il n’y a pas de période stable, vu que la désagrégation commence très tôt après que la glace ait cru à son étendu maximal. La rupture est un processus graduel qui normalement commence vers le 15 février en aval de Trois-Rivières et vers le premier mars en amont. La grande majorité de la glace disparait généralement avant le 31 mars. Par ailleurs, la vitesse d’écoulement de la rivière, ainsi que sa profondeur et son nombre de Froude le long des limites de la glace de rive sont évalués. Ceci dans la condition où la glace de rive a atteint sa répartition superficielle maximale. La vitesse est presque toujours inférieure à 1 m/s, le nombre de Froude maximal est normalement de 0,1 au dans le Lac St Pierre et de 0,2 sur le tronçon Montréal-Sorel. La profondeur de la rivière à la limite de la glace peut varier largement. À partir d’une modélisation numérique, il a été calculé que la glace de rive cause une augmentation de la vitesse de 0,1 m/s dans le chenal maritime du Lac St Pierre et du niveau d’eau de 14 cm dans le tronçon Montréal-Sorel.
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46

Duncan, Kyle. "Reconstructing surface elevation changes for the Greenland Ice Sheet (1993-2013) and analysis of Zachariae Isstrom, northeast Greenland." Thesis, State University of New York at Buffalo, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1600748.

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<p> Previous studies investigating the velocity and elevation change records of the Greenland Ice Sheet (GrIS) revealed rapid and complex changes. It is therefore imperative to determine changes with both high spatial and temporal resolutions. By fusing multiple laser altimetry data sets, the Surface Elevation Reconstruction and Change (SERAC) program is capable of reconstructing surface elevation changes with high spatial and temporal resolution over the entire GrIS. The input data include observations from NASA&rsquo;s Ice, Cloud and land Elevation Satellite (ICESat) mission (2003-2009) as well as data collected by NASA&rsquo;s Airborne Topographic Mapper (ATM) (1993-2013) and Land, Vegetation and Ice Sensor (LVIS) (2007-2012) airborne laser altimetry systems. This study extends the record of surface elevation changes over the GrIS by adding 2012 and 2013 laser altimetry data to the previous 1993-2011 record. Extending the record leads to a new, more accurate and detailed altimetry record for 1993-2013. </p><p> Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Digital Elevation Models (DEMs) are fused with laser altimetry data over Zachari&aelig; Isstr&oslash;m, northeast Greenland to analyze surface elevation changes and associated thinning rates during 1978-2014. Little to no elevation change occurred over Zachari&aelig; Isstr&oslash;m from 1978-1999, however, from 1999-2014 elevation changes near the calving front became increasingly negative and accelerated. Calving front position showed steady retreat and grounding line position has been retreating towards the interior of the ice sheet at an increasing rate from 2010-2014 when compared to the 1996-2010 period. The measured elevation changes near the calving front have brought a large portion of the glacier close to the height of flotation. If the current thinning trend continues this portion of the glacier will reach flotation within the next 2-5 years allowing for further retreat and increased vulnerability to retreat for sections of the glacier further upstream.</p>
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47

Liberale, Gabriel. "Apport de l'imagerie en fluorescence au vert d'indocyanine dans le staging et le traitement du cancer colorectal." Doctoral thesis, Universite Libre de Bruxelles, 2017. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/248402.

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Résumé:IntroductionLa chirurgie reste le seul traitement à visée curative pour les patients porteurs d’un cancer colorectal (CCR) primitif ou métastatique. L’établissement précis de l’extension de la maladie, au niveau de la tumeur primitive, des ganglions loco-régionaux et des métastases à distance représente un élément essentiel pour la prise en charge thérapeutique. Les ganglions locorégionaux et la technique du ganglion sentinellePour les patients présentant un CCR non métastatique, l’analyse pathologique des ganglions (pN) conditionne la décision d’administrer ou non une chimiothérapie adjuvante. Les patients présentant un envahissement ganglionnaire (pN+) recevront un traitement adjuvant, celui-ci n’étant le plus souvent pas indiqué chez les patients sans envahissement ganglionnaire (pN0). Près de 20 à 30% des patients classés pN0 vont cependant développer des récidives tumorales. Parmi ces patients, il est probable qu’une partie ait été sous-classée au moment du diagnostic. La technique du ganglion sentinelle (GS) permet d’identifier les ganglions les plus susceptibles d’être envahis et de réaliser des analyses anatomopathologiques plus approfondies sur un nombre plus limité d’échantillon. Cette technique est recommandée dans le cancer du sein et dans le mélanome, mais son rôle reste discuté dans le CCR. Le premier volet de cette thèse concerne les résultats d’études cliniques que nous avons menées pour évaluer le rôle de la technique du GS au bleu patenté (BP) et de l’imagerie en fluorescence (IF) au vert d’indocyanine ou indocyanine green (ICG) dans le staging ganglionnaire des patients présentant un CCR. Les principaux objectifs de ces travaux étaient d’évaluer la faisabilité de ces techniques et leur apport dans le staging des patients présentant un CCR.Notre première étude sur la technique du GS au BP, représentant la plus grande cohorte monocentrique européenne, a permis de démontrer la faisabilité de la technique. En outre, cette approche a modifié le geste chirurgical dans 12% des cas (technique in vivo) et a permis de reclasser 10% des patients initialement classés pN0 en pN+ par la réalisation de coupes sériées spécifiquement réalisées sur les ganglions démontrés comme GS. Dans une seconde étude sur la technique du GS comparant l’IF-ICG à la technique au BP, nous avons montré que ces 2 techniques étaient complémentaires, permettant d’augmenter la sensibilité globale pour la détection des métastases ganglionnaires. De plus, l’IF-ICG apparaît comme plus sensible chez les patients présentant une surcharge pondérale. En termes de sensibilité, la recherche du GS par IF est supérieure à la technique BP, ces résultats restant cependant limités, notamment en raison d’un taux élevé de faux négatifs (FN) pour les tumeurs localement avancées (pT3-4). Les métastases ganglionnaires et la carcinose péritonéaleDans le CCR, les patients métastatiques, présentant une carcinose péritonéale (CP) et/ou un envahissement ganglionnaire, ont un pronostic sombre. La chirurgie d’exérèse de la CP associée à une chimiothérapie hyperthermique intrapéritonéale (CHIP) et la réalisation de curages ganglionnaires chez les patients porteurs d’une maladie oligométastatique permettent toutefois d’obtenir des survies prolongées et parfois des guérisons, avec des résultats similaires à ceux observés chez les patients opérés pour métastases hépatiques isolées. Pour la CP, l’étendue de la maladie et la radicalité de la résection sont les principaux facteurs pronostiques de survie. La sensibilité des examens d’imagerie conventionnelle et métabolique reste cependant faible pour déterminer l’extension de la maladie péritonéale. L’évaluation de l’étendue de la CP et son exérèse sont donc essentiellement fondées sur la palpation et l’exploration visuelle réalisée durant l’intervention chirurgicale, représentant un facteur limitant pour la radicalité de la chirurgie. De façon similaire, chez les patients présentant une maladie métastatique ganglionnaire limitée, la détection peropératoire est souvent difficile, nécessitant la réalisation de curages étendus de principe, afin de s’assurer de l’exérèse des ganglions pathologiques.L’utilisation de l’IF après injection iv intra-opératoire d’ICG a été rapportée comme une technique permettant la détection de tissu tumoral tant visible que non visible (infraclinique), pouvant potentiellement aider le chirurgien et guider les gestes de résection. Aucune étude n’avait particulièrement analysé le rôle de l’IF-ICG dans la détection de CP et de métastases ganglionnaires de CCR. Le second volet de cette thèse concerne l’évaluation de l’apport de l’IF après injection iv d’ICG pour la détection de la CP et des métastases ganglionnaires dans le CCR. L’objectif primaire était de vérifier si les métastases péritonéales (MP) et ganglionnaires visibles par le chirurgien étaient effectivement détectées par l’IF-ICG peropératoire. En parallèle, nous avons évalué si l’IF-ICG permettait de détecter une maladie infraclinique, non détectée par le chirurgien dans les conditions habituelles. La première étude de cette seconde partie a permis de montrer que les MP étaient visualisées comme hyperfluorescentes à l’IF-ICG pour autant qu’elles ne soient pas d’origine mucineuse. De plus, l’IF-ICG a permis de détecter des MP non visualisées en lumière visible, permettant d’adapter le geste chirurgical et d’augmenter la radicalité de la résection dans près de 38% des cas. Dans une seconde étude, nous avons rapporté que la technique d’IF utilisée in vivo et ex vivo après injection iv d’ICG permettait d’identifier des ganglions métastatiques, détectés ou non par les imageries conventionnelles et métaboliques préopératoires. Les résultats de cette étude constituant une preuve de concept ont été ensuite confirmés dans une étude rétrospective réalisée sur l’analyse ex vivo des ganglions de patients ayant reçu une injection iv d’ICG. Dans ce travail, nous avons montré que les ganglions envahis étaient plus fluorescents que les ganglions non envahis. Toutefois, cette preuve de concept doit encore être confirmée et évaluée plus largement dans une étude prospective. Ces 2 travaux montrent donc le bénéfice potentiel de l’utilisation de l’IF après injection iv d’ICG à 2 niveaux, pour guider la chirurgie en améliorant la détection peropératoire des sites métastatiques infracliniques et pour guider l’analyse histologique, en identifiant des ganglions fluorescents sur la pièce de résection, permettant une étude anatomopathologique plus ciblée et plus approfondie. Conclusions et perspectivesNos travaux sur la recherche du GS dans le CCR par la technique au BP et à l’IF-ICG ont montré que ces techniques étaient faisables mais que leurs sensibilités restaient limitées, en particulier chez les patients porteurs de tumeurs localement avancées. Dans la CP d’origine colorectale, nous avons montré que l’IF-ICG permettait d’améliorer la stadification de la CP des patients opérés de métastases péritonéales non mucineuses, de révéler des lésions non visibles dans les conditions standards et d’améliorer la radicalité de la chirurgie. Pour la détection de ganglions métastatiques, nous avons montré que l’IF-ICG permettait, in vivo, de détecter des ganglions infracliniques durant l’intervention et ex vivo, de guider l’analyse anatomopathologique de la pièce de résection. Enfin, nous pensons que ces observations pourraient nous permettre d’élaborer un nouveau concept de GS systémique par opposition au GS classique correspondant aux ganglions de drainage anatomique de la tumeur. Nous proposons que les capacités particulières de rétention de l’ICG dans les tissus cancéreux après injection par voie systémique pourraient permettre d’identifier des sites ganglionnaires métastatiques en dehors des sites de drainage révélés par les injections de marqueurs au sein ou en périphérie de la tumeur elle-même. Pour vérifier cette hypothèse, nous avons élaboré un nouveau protocole d’une étude clinique prospective dans laquelle la détection du GS systémique après injection iv d’ICG sera comparée aux résultats obtenus suite à l’injection péritumorale de BP. Les ganglions révélés par ces 2 techniques seront recherchés ex vivo sur la pièce de résection et analysés en anatomopathologie. Outre la démonstration de métastases ganglionnaires extra-anatomiques, nous pensons que cette approche systémique pourrait permettre de réduire le taux de FN observé suite à une injection péritumorale, notamment pour les tumeurs localement avancées, celles-ci pouvant perturber le drainage lymphatique selon les voies anatomiques. Summary:This thesis reports several clinical research works on the role of indocyanine green (ICG) fluorescence imaging (FI) for the detection of colorectal tumoral tissue. We first evaluate and compare the role of ICG-FI in the detection of sentinel lymph node (SLN) in colorectal cancer (CRC) in view to upstage patients. We have reported that both techniques (blue dye and ICG-FI) are similar in term of sensitivity with a high rate of false negative results. Therefore, we think that new approaches for SLN detection should be developped in CRC. Secondarily, we evaluate the role of ICG-FI after IV ICG injection for the detection of peritoneal carcinomatosis (PC) from CRC origin. We have reported that ICG-FI is able to detect non-mucinous PM with a sensitivity of 86%. Moreover, ICG-FI was able to guide surgery modifying the surgical procedure in 38% of patients. Thirdly, we investigate the role of ICG-FI for the detection lymph node (LN) metastases. We have reported that ICG-FI performed after IV ICG injection is able to detect LN metastases both in vivo and ex vivo. These findings have been confirmed in a retrospective study. Fiinally, we propose a new protocol to evaluate a new approach for SLN detection. In comparison with the standard technique using peritumoral injection, we propose a new approach using systemic (intravenous) ICG injection. We have called this approach the 'systemic' SLN detetion. This approach will be compared with the standard one using peritumoral blue dye injection. Sensitivity, specificity of both technique will be compared. In conclusion, the results of these preliminary clinical studies using ICG-FI for tumoral staging and treatment are encouraging and further larger studies should be performed.<br>Doctorat en Sciences médicales (Médecine)<br>info:eu-repo/semantics/nonPublished
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48

Metzger, Christiane, and Johann Haag. "„Ich könnte nie wieder zu einem ‚normalen‘ Stundenplan zurück!“ – Zur Reorganisation der Lehre in einem Bachelor-Studiengang IT Security." Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6488/.

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Im Bachelor-Studiengang (B. Sc.) IT Security an der Fachhochschule St. Pölten wurde im Wintersemester 2011/12 versuchsweise die Lehrorganisation im ersten Fachsemester verändert: Die Module bzw. Teilmodule wurden nicht mehr alle parallel zueinander unterrichtet, sondern jedes Modul wurde exklusiv über einige Wochen abgehalten. Im Beitrag werden die Auswirkungen und bisherigen Erfahrungen mit dieser Reorganisation der Lehre geschildert: So haben sich die Noten im Mittel um etwa eine Note verbessert, die Zahl derjenigen Studierenden, die durch Prüfungen durchfallen, ist drastisch gesunken. Die Zufriedenheit der Studierenden und Lehrenden ist so groß, dass diese Form der Lehrorganisation im gesamten Bachelor- und auch im Masterstudiengang übernommen wird.
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49

Montross, Scott Norman. "Biogeochemistry of basal ice from Taylor Glacier, Antarctica." Diss., Montana State University, 2012. http://etd.lib.montana.edu/etd/2012/montross/MontrossS0512.pdf.

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The thesis addresses a topical and exciting question in cryospheric biology: are microorganisms capable of metabolism in debris-rich basal ice of a polar glacier? The research was carried out on debris-rich basal ice from a cold-based glacier, Taylor Glacier, McMurdo Dry Valleys, Antarctica. A key component of the research was the collection and analysis of large parallel samples of basal ice for analysis of sediment concentration and mineralogy, nutrient and ion chemistry, gas composition, isotopic gas composition, cell density and metabolic activity on individual ~1-2cm thick layers. The primary material for the thesis was from a 4 m high section of basal ice collected from a vertical shaft at the end of a 15m tunnel chainsawed into the northern margin of the Taylor Glacier. Some data was derived from ice samples collected from tunnels 500m upglacier and downglacier from the 2007 tunnel, excavated in 1999 and 2009 respectively. The main research findings presented in this dissertation are that (a) debris-rich basal ice is a viable habitat for microbial life, (b) in situ microbial heterotrophic respiration is a source of CO &acirc;‚‚ in debris-rich basal ice, and (c) microbially-mediated weathering of entrained mineral debris is a source of solute in the ice. Geologic debris in basal ice is the key component for microbial activity since it leads to a higher fraction of liquid water in the ice and provides both organic and inorganic substrates to organisms in the ice. Microbial activity in the ice produces isotopic and geochemical signatures that could be used as biomarkers for exploration of other icy systems. The results of the thesis enforce the notion that the debris-rich basal ice environment is a viable microbial habitat that supports life at temperatures below 0&Acirc;&deg;C. This has broader implications at the ice sheet scale since recent discoveries in East Antarctica, indicate significant basal ice up to 1100 m thick with approximately the same volume as the world's fourth largest freshwater lake, Lake Michigan-Huron. 'Co-authored by Mark Skidmore, Brent C. Christner, Denis Samyn, Jean Louis Tison, Reginald Lorrain, Shawn Doyle, Sean Fitzsimons, and Todd Sowers.'
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50

Stone, Megan M. "Long-range forecasting of Arctic sea ice." Thesis, Monterey, California : Naval Postgraduate School, 2010. http://edocs.nps.edu/npspubs/scholarly/theses/2010/Jun/10Jun%5FsTONE.pdf.

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Thesis (M.S. in Meteorology)--Naval Postgraduate School, June 2010.<br>Thesis Advisor(s): Murphree, Tom ; Meyer, David. "June 2010." Description based on title screen as viewed on July 14, 2010. Author(s) subject terms: Arctic, Sea Ice, Sea Ice Concentration, Beaufort Sea, Military Operations, Climate, Climatology, Climate Analysis, Climate Prediction, Long-range Forecast, Statistical Forecast, Meteorology, Arctic Oscillation, North Atlantic Oscillation, Caribbean Sea. Includes bibliographical references (p. 89-92). Also available in print.
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