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1
Melanson, Jeff A. "Seasonal and Tidal Variations of Sediment Transport Patterns in the Saint John Inner Harbour." Thesis, Fredericton: University of New Brunswick, 2012. http://hdl.handle.net/1882/44601.
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The Saint John Harbour is located along the Bay of Fundy in southern New Brunswick
and serves as the primary outlet for the Saint John River. Sediment movement
within the Saint John Harbour is a concern from both an ecological and operational
perspective. Seasonal measurements of current velocity and suspended sediment
concentration (SSC) have been obtained by deploying two acoustic Doppler current
profilers (ADCPs) in the inner harbour. ADCP observations spanned several months
and were nearly continuous, thus allowing for an in-depth analysis of meteorological
and tidal influences on observed hydrodynamics. A comparative assessment was
conducted for spring and neap tides, storm surges, and changes in fluvial input. It
was observed at both deployment locations that the intruding salt wedge frequently
contained high SSC. The salt wedge is believed to be a major contributor of sediment
accretion in the inner harbour, particularly during winter storm surges when river
discharge is reduced. The Courtenay Bay Channel was observed to be more sensitive
to river level, with only winter storms resulting in a landward average sediment flux.
Observations made near Courtenay Bay Channel also suggested the presence of a
cross channel flow pattern from an adjacent inter-tidal mudflat. This cross channel
flow was only observed during spring freshet conditions and contained high SSC.
Hydrodynamic observations from the study were compared with published estuarine
theory. Results of the study will help to further define hydrodynamic processes in
the Saint John Harbour.
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Milbers, Zoja. "Eigenvalue Problem for the 1-Laplace Operator." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1238150433158-43544.
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We consider the eigenvalue problem associated to the 1-Laplace operator. We define higher eigensolutions by means of weak slope and establish existence of a sequence of eigensolutions by using nonsmooth critical point theory. In addition, we deduce a new necessary condition for the first eigenvalue of the 1-Laplace operator by means of inner variationsWir betrachten das zum 1-Laplace-Operator gehörige Eigenwertproblem. Wir definieren höhere Eigenlösungen mittels weak slope und weisen die Existenz einer Folge von Eigenlösungen nach, indem wir die nichtglatte Theorie kritischer Punkte anwenden. Zusätzlich leiten wir eine neue notwendige Bedingung für den ersten Eigenwert des 1-Laplace-Operators mittels innerer Variationen her
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Beaudet, Amélie. "Caractérisation des structures crânio-dentaires internes des cercopithécoïdes et étude diachronique de leurs variations morphologiques dans la séquence Plio-Pléistocène sud-africaine." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30297/document.
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Les cadres temporel, géographique et environnemental associés à l'émergence et l'évolution des premiers homininés en Afrique du Sud pendant le Plio-Pléistocène constituent des éléments clés dans la compréhension de l'histoire de la lignée humaine. Les cercopithécoïdes, relativement abondants dans les dépôts fossilifères du Néogène africain et quasi systématiquement associés aux restes d'homininés, représentent des marqueurs biochronologiques et des indicateurs écologiques sensibles. Toutefois, en se basant seulement sur les critères morphologiques traditionnels, la systématique du registre cercopithécoïde fossile reste encore incertaine. Afin de mieux caractériser leur paléobiodiversité, nous avons détaillé par des techniques d'imagerie à haute résolution les restes crânio-dentaires de 91 spécimens cercopithécoïdes provenant des sites de Makapansgat, Taung, Sterkfontein, Kromdraai et Swartkrans. En particulier, nous avons mesuré et comparé les variations dans l'organisation endostructurale dentaire, la conformation du labyrinthe osseux et l'architecture endocrânienne à travers l'application de méthodes statistiques et de modélisation virtuelle (e.g., morphométrie géométrique, modèles déformables). À titre comparatif, nous avons également intégré dans nos analyses un échantillon de 80 spécimens cercopithécoïdes actuels. En plus de l'identification de caractères nouveaux et pertinents pour la diagnose des taxons fossiles, nos résultats mettent en évidence des biomarqueurs utiles pour la reconstruction des contextes paléoenvironnementaux et biochronologiques, notamment en ce qui concerne la morphologie de la jonction émail-dentine et l'architecture néocorticale. L'estimation de la paléobiodiversité révèle un certain degré d'homogénéité morphologique pour quelques taxons papionines qui plaide en faveur d'une réduction du nombre d'espèces effectivement présentes dans les gisements fossilifères sud-africainsThe temporal, geographical and environmental frameworks of the early hominin emergence and evolution in South Africa during the Plio-Pleistocene are key elements for the understanding of the human lineage history. The cercopithecoids, relatively abundant in the African Neogene fossiliferous deposits and almost invariably associated with hominin remains, represent sensitive biochronological markers and ecological indicators. However, based on traditional morphological criteria only, the systematics of the cercopithecoid fossil record remains uncertain. In order to better characterize their paleobiodiversity, by means of high-resolution imaging techniques we have detailed 91 South African cercopithecoid craniodental specimens from the sites of Makapansgat, Taung, Sterkfontein, Kromdraai and Swartkrans. More specifically, we measured and compared the variation in dental endostructural organization, bony labyrinth conformation and endocranial architecture through the application of statistical and virtual modeling methods (e.g., geometric morphometrics, deformation-based models). For comparative purposes, we also integrated in our analyses a sample consisting of 80 extant cercopithecoid specimens. Besides the identification of some new characters suitable for the diagnosis of fossil taxa, our results reveal biomarkers useful for the reconstruction of paleoenvironmental and biochronological contexts, notably based on the enamel-dentine junction morphology and the neocortical architecture. The paleobiodiversity assessment highlights a certain degree of morphological homogeneity for some of the papionin taxa and suggests a reduction of the number of species actually present in the South African fossiliferous deposits
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Challa, Rohith Prasad. "SR Flip-Flop Based Physically Unclonable Function (PUF) for Hardware Security." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7669.
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Physically Unclonable Functions (PUFs) are now widely being used to uniquely identify Integrated Circuits (ICs). In this work, we propose a novel Set-Reset (SR) Flip-flop based PUF design. For a NAND gate based SR flip-flop, the input condition S (Set) = 1 and R (Reset) = 1 must be avoided as it is an inconsistent condition. When S=R=1 is applied followed by S=R=0, then the outputs Q and Q' undergo race condition and depending on the delays of the NAND gates in the feedback path, the output Q can settle at either 0 or 1. Because of process variations in an IC, the NAND delays are statistical in nature. Thus, for a given SR FF based $n$-bit register implemented in an IC, when we apply S=R=1 to all flip-flops followed by S=R=0, then we obtain an $n$ bit string that can be interpreted as a signature of the chip. Due to process variations, the signature is highly likely to be unique for an IC. We validated the proposed idea by SPICE-level simulations for 90nm, 45nm, and 32nm designs for both intra- and inter-chip variations to establish the robustness of the proposed PUF. Experimental results for 16-, 32-, 64-, and 128-bit registers based on Monte-Carlo simulations demonstrate that the proposed PUF is robust. The main advantage of the proposed PUF is that there is very little area overhead as we can reuse existing registers in the design.
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Beckett, Sophie. "Inter-species variation in bone mineral." Thesis, DMAS, 2011. http://dspace.lib.cranfield.ac.uk/handle/1826/4912.
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Bone is a complex heterogeneous composite material with organic and inorganic components. The inorganic component; bone mineral, is a poorly crystalline, non-stoichiometric form of calcium hydroxylapatite. A model for the general structure and composition of bone mineral has been established within the literature. However, the nature and extent of variation in bone mineral composition and structure has, to date, been poorly understood. This situation also applies to the general response of bone mineral to heat treatment and variation in this response. This thesis presents the results of an investigation of inter-species variation in bone mineral characteristics of unheated bone and bone heated to temperatures of 600 °C and 1400 °C. Twelve different animal species were investigated, including human bone. X-ray diffraction analysis was the primary analytical technique employed. The Rietveld method of full profile fitting of diffraction data was used to quantitatively investigate characteristics of unheated and heated bone such as the weight percentages of the thermal decomposition products of bone mineral. Infrared spectroscopy, inductively coupled plasma – atomic emission spectrometry, pyrohydrolysis – ion chromatography and combustion – gas chromatography were also employed to obtain further data regarding the chemical composition of bone. Biological ii control of bone mineral composition and structure and the chemical basis for the variation observed within the results were explored. Significant inter-species variation in bone mineral composition and structure and also, the response of bone to heat treatment have been demonstrated by the results of this thesis. In particular, human bone is significantly different from bone of all other species investigated.
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Noreen, Shumaila. "Inter and intraspecific clock gene variations in Drosophila." Thesis, University of Leicester, 2013. http://hdl.handle.net/2381/28116.
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Circadian clock genes have undergone many structural and functional modifications during their evolution. Even in closely related evolutionary lineages, the circadian molecules can be variable and perform the same or different tasks. I studied three important clock genes Cryptochrome (cry), period (per) and timeless (tim) in D. melanogaster. The study of the cry L232H polymorphism revealed no difference in the distribution of the two alleles across Europe. Population cages with different initial cry allelic frequencies, nevertheless converged to a ~1:1 ratio after 16 generation, mimicking natural population frequencies. The analysis of locomotor activity in the laboratory showed a temporal difference in the phase of activity for the males and females, with female cry[superscript HH] and male cry[superscript LL] active significantly earlier than other genotypes. If this increases the probability of disassortative mating, intermediate frequencies of the two alleles might be generated. I also studied the intermolecular co-evolution between the two interacting circadian proteins TIM and PER. The individual per and tim transgenes from D. pseudoobscura in D. melanogaster mutant hosts showed more than 50% rhythmicity but very long (29h) period for per and very short period (21h) for tim. By combining them in the D. melanogaster double mutant background, the hemizygous flies showed no improvement in rhythmicity but an excellent rescue of periodicity of ~24h. This suggest that TIM and PER may form a heterospecific coevolved module that interacts more robustly with the other host clock proteins. Finally, using my transgenes and null mutants I showed that Par Domain Protein 1ε (Pdp1ε) participates in the expression of residual rhythmicity of mutants for the negative limb of the circadian clock.
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AL-KHUDHAIR, AHMED S. "Inter - and Intra-population Genetic Variations in Humans." University of Toledo Health Science Campus / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=mco1418259978.
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Donelson, Nathan Cooper. "Inter- and Intraspecific Variation in the Superfamily Pneumoroidea." Bowling Green State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1194043244.
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Perez, Marcos Francisco 1987. "Inter-individual physiological variation in the nematode Caenorhabditis elegans." Doctoral thesis, Universitat Pompeu Fabra, 2018. http://hdl.handle.net/10803/664089.
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For unknown reasons, genetically identical animals often differ substantially in their phenotypic traits, even in a controlled environment. Here I investigate the causes of inter-individual physiological variation using a model organism, the nematode Caenorhabditis elegans. Isogenic nematodes vary in their size at hatching, speed of development, growth rate, starvation resistance and fecundity. I show that much of this variation is due to the age of an individual’s mother, with young mothers producing progeny impaired for many traits. The underlying molecular mechanism for multiple traits is a progressive, age-dependent increase in the maternal provisioning of a lipoprotein complex, yolk/vitellogenin, to embryos. The production of sub-optimal progeny by young mothers likely reflects a trade-off between the competing fitness traits of a short generation time and progeny survival and fecundity. These results identify age-dependent changes in maternal provisioning to embryos as an important source of phenotypic variation throughout the life of an animal.Por causas desconocidas, animales idénticos genéticamente suelen variar sustancialmente en sus rasgos fenotípicos, aunque el ambiente en el que habiten sea el mismo. Aquí investigo las causas de variación fisiológica entre individuos utilizando un organismo modelo, el nematodo Caenorhabditis elegans. Nematodos isogénicos varían en su tamaño al nacer, en su velocidad de crecimiento y desarrollo, en su resistencia a la privación de alimento y en su fecundidad. Muestro que muchas de estas variaciones se deben a la edad de la madre del individuo, con las madres jóvenes engendrando a progenie peor en muchos respetos. Para muchos rasgos fenotípicos, el mecanismo molecular subyacente es un aumento progresivo con la edad de la madre de la provisión de un complejo lipoproteínico, yema/vitellogenin, a los embriones. Ecológicamente, es probable que la producción de progenie inferior por parte de las madres jóvenes esté compensada por la ventaja opuesta de tener un tiempo generacional corto. Los resultados presentados destacan los cambios en la provisión maternal de recursos a los embriones como una fuente significativa de variación fenotípica a lo largo de la vida de un animal.
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Bourne, Geoffrey S. "Actinide and fission product activity variations in inter-tidal marine macrophytes." Thesis, Cardiff Metropolitan University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306854.
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Wahid, Ridwan Languages & Linguistics Faculty of Arts & Social Sciences UNSW. "The use of articles in inner and outer circle varieties of English: a comparative corpus-based study." Awarded By:University of New South Wales. Languages & Linguistics, 2009. http://handle.unsw.edu.au/1959.4/44525.
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Articles continue to be one of the most puzzling aspects of English grammar. This thesis investigates article use variation in two groups of English varieties: Inner Circle and Outer Circle. The first group, comprising British English, American English, Australian English and New Zealand English, represents English varieties in their traditional contexts. The second group, consisting of Singapore English, Indian English, Philippine English and Kenyan English, represents varieties which are deeply entrenched in their communities due to colonial roots. The study is premised on the naturalness of corpus data. Three corpus-based analyses were conducted to investigate articles and their frequency, collocation and usage types. The frequency analysis revealed that articles are idiosyncratically used by the varieties with no clear divide between the two groups. Text types, on the other hand, emerged as a more powerful determinant of the observed frequencies. It was found that fewer articles were used in spoken language. In the collocational analysis, the varieties were found to favour different complementation patterns for two-word and multiple-world clusters. The Inner Circle varieties, however, shared more complementation patterns among them, demonstrating greater stability in terms of variation. Finally the analysis of usage types discovered marked or untypical patterns of use in the Outer Circle groups structural and situational definites. A number of untypical usages of first-mention/quantitative 'a/an' were also found in this group. In the same analysis, a case study of house uncovered a few marked uses of ??, which signalled the null form but not the zero article. Although the collective findings in this study indicate that article use in both groups of varieties has more similarities than differences, the latter leave more impression on observers. These differences can be attributed to such diverse factors as text types, socio-cultural content of collocates, specificity, recategorisation of countness, indiscriminate rule application and ungrammaticality. Theoretically, however, the variation can be captured by the application of Chestermans three composite meanings of definiteness locatability, inclusiveness and extensivity and their permutations. As an instance of nativisation, article use in the Outer Circle is limited in its diffusion. The observed innovations rarely creep into more formal registers.
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Ismail, Hanadi. "Suburbia and the inner-city : patterns of linguistic variation and change in Damascus." Thesis, University of Essex, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446042.
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Laporte, Marie-Aline. "Contribution à la modélisation de l’absorption du cadmium par les racines du tournesol (Helianthus annuus L.) en relation avec l’architecture racinaire." Thesis, Bordeaux 1, 2013. http://www.theses.fr/2013BOR15214/document.
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Le cadmium (Cd) est naturellement présent dans les sols qui sont aussi enrichis par l'activité humaine. Le Cd contamine les produits végétaux alimentaires car il est absorbé par les racines des plantes. Elément toxique pour les organismes vivants, les concentrations dans les produits consommés sont soumises aux règlementations pour l’alimentation humaine et animale. Il est donc nécessaire de comprendre le transfert sol-organe consommé du Cd, spécialement pour le tournesol (Helianthus annuus L.), notre plante modèle, pouvant accumuler plus de Cd que d’autre plantes cultivées. Ce travail a testé l'hypothèse que la quantité de Cd absorbée par le système racinaire du tournesol était liée à l'architecture de ce dernier. Nous avons caractérisé au niveau des racines individuelles une variation longitudinale de l’influx d'absorption du Cd2+ en lien avec le milieu de culture, l'ordre et l'âge des racines. Ces variations ont été attribuées à la dynamique de développement des barrières apoplasmiques (dépôts de cellulose lignine et subérine) qui limitent l'internalisation du Cd2+ dans le cytoplasme cellulaire. Par simulation, il a été montré que ces variations pouvaient théoriquement impacter l'absorption totale de Cd2+ en fonction de l'architecture racinaire en hydroponie mais beaucoup moins sur substrat solide (sable). En outre, une comparaison de 14 cultivars de tournesol cultivé en hydroponie a montré que la variabilité des teneurs en Cd dans les parties aériennes était plutôt liée à des différences d'absorption indépendantes de l'architecture racinaire et à des variations de répartition dans la plante. Les variations longitudinales d'absorption du Cd peuvent alors être considérées comme mineures face à des variations inter-cultivars dont l'origine reste à élucider. Dans une optique de modélisation du prélèvement total en conditions de sol, il serait alors possible de ne considérer qu’un influx moyen de Cd pour la totalité du système racinaire indépendamment de son architectureCadmium (Cd) is naturally occurring in soils that are also enriched by human activity. Cd contaminates food crops because of its absorption by plant roots. Because it is a toxic element for living organisms, its concentrations in food and feed plant products are subjected to regulatory limits. Therefore, it is necessary to understand the transfer of this metal from the soil to the edible plant part, especially for sunflower (Helianthus annuus L.), our model plant that can accumulate more Cd than other crop species. This study tested the hypothesis that the amount of Cd absorbed by sunflower was related to the root architecture. We characterized, at the individual roots level, a longitudinal variation of the influx of Cd2+ absorption in relation with the culture medium, the order and the age of roots. These variations were attributed to the development of apoplastic barriers (cellulose, lignin and suberin deposition) that restrict the absorption of Cd2+ into the cytosol. By simulation, it has been shown that these variations could theoritically impact the total absorption of Cd2+ in hydroponics depending on the root architecture while in solid substrate (sand) the impact was much more limited. Furthermore, a comparison of 14 sunflower cultivars showed that the variability in Cd concentrations in shoots was rather due to differences in absorption independent of root architecture and in variations in the root to shoot distribution. The longitudinal variation in the Cd root influx can then be considered of minor importance compared to the between cultivar variability in Cd uptake, the origin of which remains to be determined. In the perspective of modelling the total uptake of Cd in soil conditions, it could then be possible to assume a global mean influx of Cd independent of the root architecture
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Sethabouppha, Benjabhorn. "Inter-Individual Variation in CYP3A4 and CYP3A5- Mediated Drug Metabolism." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492887.
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Cytochrome P450 enzymes, especially those of the CYP3A family, play a major role in the metabolism of many drugs.' Patient response to drugs metabolized by CYP3A4 and CYP3A5 varies considerably and part of this variability is due to genetic polymorphism ot the CYP3A5 enzyme. In this study, human liver microsomes (HLM) were prepared from a panel of 26 liver samples and total soluble protein was evaluated. The CYP3A5 and CYP3A4 protein contents were determined by Western blotting and metabolic studies of individual HLM were performed with three selected substrates, ALP, MDZ and TST using HPLC. Results from the 26 HLM preparations revealed a high variability in CYP3A4 (366.7-1.06 pmol/mg protein, 346 fold) and CYP3A5 (4.26 -0.14 pmol/mig protein, 30 fold) content. As might be expected, the two samples with the CYP3A5*l/*3 genotype expressed higher CYP3A5 protein level than the other 24 samples (CYP3A5*3/*3) indicating the consequence of the CYP3A5*1 allele on CYP3A5 protein expression.
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Malhotra, Garima. "HF Radar Observations of Inter-Annual variations in Mid-Latitude Mesospheric Winds." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/78084.
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The equatorial Quasi Biennial Oscillation (QBO) is known to be an important source of inter-annual variability at mid and high latitudes in both hemispheres. Coupling between QBO and the polar vortex has been extensively studied over the past few decades, however, less is known about QBO influences in the mid-latitude mesosphere. One reason for this is the relative lack of instrumentation available to study mesospheric dynamics at mid-latitudes. In this study, we have used the mid-latitude SuperDARN HF radar at Saskatoon (52.16 N, -106.53 E) to study inter-annual variation in mesospheric winds. The specific aim was to determine whether or not a Quasi Biennial signature could be identified in the Saskatoon mesosphere, and if so, to understand its relationship with the equatorial stratospheric QBO. To achieve this goal, a technique has been developed which extracts meteor echoes from SuperDARN near-range gates and then applies least-squares fitting across all radar beam directions to calculate hourly averages of the zonal and meridional components of the mesospheric neutral wind. Subsequent analysis of 13 years (2002-2014) of zonal wind data produced using this technique indicates that there is indeed a significant QBO signature present in Saskatoon mesospheric winds during late winter (Jan-Feb). This mesospheric QBO signature is in opposite phase with the equatorial stratospheric QBO, such that when QBO (at 50 hPa) is in its easterly (westerly) phase, the late winter winds in Saskatoon mesosphere become more (less) westerly. To further examine the source of the signature, we also analyzed winds in the Saskatoon stratosphere between 5 hPa and 70 hPa using the ECMWF ERA-Interim reanalysis data set, and found that the late winter stratospheric winds become less (more) westerly when QBO is easterly (westerly). This QBO signature in the mid-latitude stratospheric winds is essentially the same as that observed for the polar vortex in previous studies but it is opposite in phase to the mid-latitude mesospheric QBO. We therefore conclude that filtering of gravity waves through QBO-modulated stratospheric winds plays a major role in generating the mesospheric QBO signature we have identified in the Saskatoon HF radar data. When the Saskatoon stratospheric winds are anomalously westward during easterly QBO, the gravity waves having westward momentum might be filtered out, depositing a net eastward momentum in the mesosphere as they propagate upwards. This would result in increased westerly mesospheric winds at Saskatoon. The opposite would happen when the equatorial QBO is westerly.Master of Science
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Kobuse, Hiroe. "Visualizing variations in organizational safety culture across an inter-hospital multifaceted workforce." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215217.
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Sangster, Catherine M. "Inter- and intra-speaker variation in Liverpool English : a sociophonetic study." Thesis, University of Oxford, 2002. http://ora.ox.ac.uk/objects/uuid:6d5cbd34-73ab-4c22-b341-9253eac94b3c.
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This thesis presents experiments and interviews which investigate pronunciation variation in the Liverpool accents of young speakers. Experiment One investigates inter-speaker variation, Experiment Two investigates intra-speaker variation, and Experiment Three investigates both inter- and intra-speaker variation. These three experiments are conducted from a sociophonetic perspective, with controlled elicitation of natural speech and acoustic analysis of speech data. The experimental investigations are complemented by interviews, which incorporate the perceptions and opinions of speakers of Liverpool English into the study. The study makes several contributions to the field of sociolinguistic research. It provides a new examination of Liverpool English. Experiment One is specifically designed to explore one of its most complex and ill-defined phonetic features, the realisation of plosives as affricates or fricatives. In addition to this phonetic investigation, Experiment One also examines sociolinguistic variation in this feature, and shows that speakers' individual attributes (such as their social networks and their plans for the future) are as relevant to variation as their socio-economic status. The study also makes important methodological contributions. Instrumental phonetic techniques and standards are successfully applied to sociolinguistic investigation conducted in the field. An interdisciplinary approach, bringing together qualitative interviews and sociophonetic experiments, is adopted. A new quiz-questionnaire technique for data collection, which should prove useful for many kinds of future sociolinguistic research, is developed for Experiment Three. Finally, Experiment Three tests many accounts and models of intra-speaker variation. Speakers are shown to vary their pronunciation as the speech situation varies, but not all the seven phonetic variables investigated show the same patterns of variation. Speakers vary their pronunciation according to audience, and also according to topic. Speakers with a high level of ambition vary their pronunciation of certain phonetic variables more than those with a lower level of ambition, and female speakers vary their pronunciation more than male speakers.
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Sathyan, Rekha. "Intra- and inter-population variation in the bladder grasshopper Bullacris unicolor." University of the Western Cape, 2014. http://hdl.handle.net/11394/8215.
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Masters of ScienceAlthough the processes that promote biodiversity and speciation remain poorly understood, ecological factors are thought to be one of the causal agents responsible for promoting variation. Bladder grasshoppers (Orthoptera; Pneumoroidea) are a group of endemic southern African insects that provide an ideal model system to study the role of ecology in speciation. All species rely on acoustic communication for mate location, with males producing an extremely loud advertisement call that is highly species specific. Any alteration to the male call would thus likely have implications for species integrity. In this study, I examined geographic variation as well as potential ecological drivers of biological diversity within Bullacris unicolor, a variable and wide-ranging species of bladder grasshopper. The main aims of the study were to characterise the extent of acoustic and morphological variation among individuals sampled from five geographic locations and to correlate this variation with environmental data and host plant use. At the inter-population level, I found significant differences between populations with respect to both morphological and acoustic characters. Results of multivariate analyses showed significant differences in the body length, pronotum length and head width of males and in the pronotum length, abdomen width and head width of females. Similarly, the acoustic signals of males from the five populations differed significantly in both temporal and frequency components, with all but one variable (peak frequency of the introductory syllables) showing a significant difference. However, there was no correlation between morphological and acoustic variables among populations, and acoustic characters showed far greater divergence among populations than did morphology. In both males and females, the morphological variables that differed among populations were negatively correlated with mean annual temperature, indicating that grasshoppers are larger in areas with lower temperatures. Also, some of the call characteristics of males were correlated with temperature, precipitation, altitude, and slope. Although grasshoppers were observed feeding on a range of host plant species, neither morphology nor signal characteristics were found to vary according to host plant. At the intra-population level, multivariate analyses revealed that all acoustic characters differed significantly among individuals. Morphology may be influencing signal properties within a population to some extent as there were significant correlations between some of the call characters and both abdomen width and tibia length, with lengths of these two morphological variables being positively correlated with temporal components of the call and abdomen width being negatively correlated with frequency components. I also found a significant difference in the carrier frequency of male calls, as well as in some of the morphological characters of males and females, according to host plant. This indicates that host plant use has a greater effect on variation at the intra-population level than at the interpopulation level. In conclusion, the results of my study reveal significant variation in the morphology and acoustic signals of B. unicolor, both within and among populations, and suggest that this variation is at least partially related to ecological factors.
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Berry, Adrian K. "Characteristics, Evolution, and Lateral Variation of Lower Cretaceous Supradetachment Basins in the Daqing Shan, Inner Mongolia, China." DigitalCommons@USU, 2003. https://digitalcommons.usu.edu/etd/6725.
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Lower Cretaceous basins associated with the Hohhot detachment in the Daqing Shan of Inner Mongolia, China, allow us to better understand the tectonic evolution of extensional basins formed in association with detachment faulting and metamorphic core complex formation. The six basins, informally named N1, N2, S1, S2, S3, and S4, are located in different structural settings, or depozones, throughout the detachment-metamorphic core complex setting, and although all basins are consistent with previously proposed models for supradetachment basin sedimentation, second-order variability in sedimentary style is exerted by these distinct structural settings. The basins are composed of coarse, predominantly footwall derived, conglomerate deposited by masswasting and alluvial fan processes. Paleocurrent direction is generally southerly, indicating transverse transport away from the bounding detachment fault.
Two of the basins, N2 and S3, provide us with an understanding of the temporal evolution of supradetachment basins in the upper plate of a metamorphic core complex. These basins were joined in their early stages, but were later separated as extensional unroofing exhumed the lower plate of the core complex and folded the master detachment fault, causing it to propagate a new splay to the surface. Continued extension was accommodated on this new splay, allowing for continued deposition of Lower Cretaceous strata above the detachment fault on the southern flank of the Daqing Shan antiform. Another basin, S2, displays the same stratigraphy and records a similar evolution, but we speculate that it formed separately in a primary corrugation of the master detachment fault. The only unit exposed in basin S4, located near the eastern end of the detachment, is the uppermost unit. Paleocurrent and provenance data are similar to other basins. Thus, it strongly resembles the other basins in spite of the magnitude of extension. Basin S1 is located in an intra-hanging wall setting and resembles the other basins with the exception of a centrally located fine-grained interval. Basin N1 was filled by similar depositional processes, but the proportions of fill that these processes are responsible for is variable in comparison to the other Lower Cretaceous basins in the Daqing Shan. This study establishes that the basins described are all of similar geometry and depositional style, and that supradetachment basins of this style may occur in various positions within a detachment-metamorphic core complex setting, regardless of proximity to the exhumed metamorphic core and magnitude of extension.
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Gazovic, Michal [Verfasser]. "Inter-and intra-annual variations in carbon fluxes in boreal peatlands / Michal Gazovic." Greifswald : Universitätsbibliothek Greifswald, 2012. http://d-nb.info/1021054798/34.
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Osman, Abdimajid. "Studies on warfarin treatment with emphasis on inter-individual variations and drug monitoring." Doctoral thesis, Linköping : Linköping University, 2007. http://www.bibl.liu.se/liupubl/disp/disp2007/med1000s.pdf.
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Maranhão, Maria Olivia Amato. "Variações geomorfológicas inter-decadais da Barreira Costeira do Itapocú – SC, Brasil." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/132265.
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A Barreira Costeira do Itapocú está localizada na porção norte do litoral do estado de Santa Catarina sobre os domínios dos municípios de Araquari e Barra Velha. Em sua porção central a barreira apresenta-se segmentada por influência da desembocadura do rio Itapocú. Registros históricos evidenciam a ocorrência comum, na barreira, de episódios de transposição de sedimentos devido à ocorrência de eventos de sobrelavagem. A barreira e os subambientes associados foram mapeados para os anos de 1938, 1957, 1978, 2005 e 2012. Adicionalmente, foram aplicados três índices de vulnerabilidade para os depósitos de sobrelavagem, conforme metodologia proposta por Garcia et al. (2010) – OSR, MOIR e CBO, e foram analisados os parâmetros granulométricos do sistema praia-duna atual e dos depositos de sobrelavagem em dois perfis transversais à barreira. A análise geomorfológica mostrou que as principais modificações observadas ao longo do tempo na BCI estiveram relacionadas à migração do canal de conexão da laguna com o oceano, anteriormente à sua fixação, bem como a eventos de sobrelavagem da barreira. Os depósitos de sobrelavagem apresentaram elevada frequência de ocorrência ao longo da barreira (OSR), onde a maior pôde ser observada no ano de 1957, atingindo 42% de todo o comprimento da barreira, em seu setor sul, e 60% no setor norte. Este padrão apresentou diminuição ao longo do tempo, e em 2012 cerca de 1% do comprimento do setor sul da barreira costeira apresentou sobrelavagem, enquanto o setor norte exibiu 19%. MOIR, índice referente às intrusões históricas de sobrelavagem e representando a recorrência de um máximo de intrusão, foi aplicado em intervalos de 10 metros e mostrou que eventos de transposição de sedimentos tendem a ocorrer todos os anos na área estudada, atingindo até 40 metros de intrusão. Para o ultimo ano de análise, 2012, o índice CBO apresentou três casos de valor máximo, indicando máxima vulnerabilidade de um rompimento da barreira costeira. No estudo comparativo entre os diferentes compartimentos do sistema praia-duna e dos depósitos de sobrelavagem não foi possível distinguir um claro padrão entre os subambientes com base nos parâmetros granulométricos. Entretanto, este padrão de não distinção pode indicar a usual influência de processos marinhos costeiros de sobrelavagem, atuantes sobre o sistema deposicional eólico.The Itapocú coastal barrier is located in the northern coast of Santa Catarina State, on the domain of Barra Velha and Araquari cities. In its central part the barrier is segmented due to the influence of the Itapocú river mouth. Historical records demonstrate that the barrier experiments frequent overwash events. The barrier and associated environments were mapped for 1938, 1957, 1978, 2005 and 2012 dates. Additionally, three vulnerability indexes to the washover deposits were applied, according to Garcia et al. (2010) – OSR, MOIR and CBO, and the granulometric properties were analyzed for the modern beach-dune system and washover deposits in two cross sections. The morphological analysis showed that the main changes observed were related to inlet migration, before its fixation in 2011, and also to overwash events. The washover deposits showed high frequency of occurrence along the barrier (OSR), with the greater occurring in 1957, reaching 42% of its entire length in the south, and 60% in the north section. This pattern presented a decrease behavior over time, and in 2012 approximately 1% of the barrier length was overwashed in the south section and 19% in the north. The index MOIR, related to historical sediment intrusions of overwash processes, and representing a maximum intrusion was applied in 10m intervals and showed that washover events tend to occur in all years in the ICB, reaching 40m of intrusion. For the last year analyzed, 2012, the CBO index showed 3 situations of maximum intrusion, indicating 100% of barrier breaching vulnerability. In the comparative granulometric study, it was not possible to characterize the environmental deposits based on the granulometric parameters. However, non-discretize pattern can indicate the influence of coastal marine processes (overwash) acting over the eolian deposits.
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Landrum, Carla. "MAPPING AND DECOMPOSING SCALE-DEPENDENT SOIL MOISTURE VARIABILITY WITHIN AN INNER BLUEGRASS LANDSCAPE." UKnowledge, 2013. http://uknowledge.uky.edu/pss_etds/34.
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There is a shared desire among public and private sectors to make more reliable predictions, accurate mapping, and appropriate scaling of soil moisture and associated parameters across landscapes. A discrepancy often exists between the scale at which soil hydrologic properties are measured and the scale at which they are modeled for management purposes. Moreover, little is known about the relative importance of hydrologic modeling parameters as soil moisture fluctuates with time. More research is needed to establish which observation scales in space and time are optimal for managing soil moisture variation over large spatial extents and how these scales are affected by fluctuations in soil moisture content with time. This research fuses high resolution geoelectric and light detection and ranging (LiDAR) as auxiliary measures to support sparse direct soil sampling over a 40 hectare inner BluegrassKentucky (USA) landscape. A Veris 3100 was used to measure shallow and deep apparent electrical conductivity (aEC) in tandem with soil moisture sampling on three separate dates with ascending soil moisture contents ranging from plant wilting point to near field capacity. Terrain attributes were produced from 2010 LiDAR ground returns collected at ≤1 m nominal pulse spacing. Exploratory statistics revealed several variables best associate with soil moisture, including terrain features (slope, profile curvature, and elevation), soil physical and chemical properties (calcium, cation exchange capacity, organic matter, clay and sand) and aEC for each date. Multivariate geostatistics, time stability analyses, and spatial regression were performed to characterize scale-dependent soil moisture patterns in space with time to determine which soil-terrain parameters influence soil moisture distribution. Results showed that soil moisture variation was time stable across the landscape and primarily associated with long-range (~250 m) soil physicochemical properties. When the soils approached field capacity, however, there was a shift in relative importance from long-range soil physicochemical properties to short-range (~70 m) terrain attributes, albeit this shift did not cause time instability. Results obtained suggest soil moisture’s interaction with soil-terrain parameters is time dependent and this dependence influences which observation scale is optimal to sample and manage soil moisture variation.
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Anderson, Ian C., of Western Sydney Nepean University, of Science Engineering and Technology Faculty, and School of Science. "Inter- and intraspecific variation in Pisolithus from central and eastern mainland Australia." THESIS_FST_SS_Anderson_I.xml, 2000. http://handle.uws.edu.au:8081/1959.7/237.
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Pisolithus is an important ectomycorrhizal genus world-wide, however to date we remain largely ignorant of the genetic and functional variation that exists within isolates of this genus. Fifty-three isolates of Pisolithus were obtained from various locations in central and eastern Australia and genetic variation within the isolates was assessed using ITS-RFLP and ITS sequencing analyses. RFLP analysis initially grouped the isolates into eight RFLP types. Neighbour-joining analysis of ITS sequences with Pisolithus ITS sequences available in databases clustered the majority of isolates into four groups within two major clades, each comprising isolates of similar basidiospre characteristics. Most Australian isolates correspond with recent provisional descriptions of P. albus or P. marmoratus. One isolate (LJ30) had low sequence identity (61.6-78.0%) to the other isolates and probably represents a separate undescribed Australian species. Significant intraspecific variation was observed in ITS-RFLP profiles for the putative P. albus isolates, suggesting that the sole use of RFLP analysis in diversity assessment may over-estimate Pisolithus species richness. Investigations were also initiated to identify if a relationship exists between genetic and physiological diversity in Australian Pisolithus. It is, however, clear that extensive physiological variation exists in Australian Pisolithus isolates. The size and distribution of genets of Australian Pisolithus species I and II ( putative P. albus and P. marmoratus) was also assessed using microsatellite-primed PCR to gain a better understanding of the likely distribution of underground mycelial networks and possible reproduction strategies in native soils. The data demonstrate that both species have the ability to be long-lived and extend for significant distances in native soils in undisturbed conditions. The field site for Pisolithus species I, however, also contained of a large number of small individuals suggesting that this species may employ a life-history strategy combining r-, C and S characteristics depending on local soil conditionsDoctor of Philosophy (PhD)
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Anderson, Ian C. "Inter- and intraspecific variation in Pisolithus from central and eastern mainland Australia /." View thesis, 2000. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030724.145538/index.html.
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Thesis (Ph.D.)--University of Western Sydney, 2000."Thesis submitted in accordance with the requirements for the degree of Doctor of Philosophy, School of Science, University of Western Sydney (Nepean)." "October 2000." Bibliography : leaves 143-179.
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Sculley, Dean Vincent. "Inter-individual variation in saliva antioxidant status in relation to periodontal disease." Thesis, University of Leicester, 2004. http://hdl.handle.net/2381/9299.
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Free radicals have been implicated in the aetiology of many human disease states, including periodontal disease (PD). Saliva contains an array of antioxidants that neutralise the harmful effects of free radical formation within the oral cavity. Increased salivary antioxidant capacity may limit oxidative tissue damage and improve the health of the gingival tissues. In this thesis, the antioxidant profile of saliva was assessed in relation to PD severity. Salivary protein carbonyl concentration was assessed as a biomarker of oxidative tissue damage. Urate, ascorbate and albumin contributed 85% of the total scavenging antioxidant capacity (TAA) which followed a diurnal rhythm (peak 5.00pm, nadir 3.00am). Salivary antioxidant flow rate was significantly lower in individuals with severe PD (TAA 0.210 f 0.02 μM/ml/min) than those with healthy gingivae (TAA 0.270 ± 0.02 PM/ml/min) (p<0.05). Oxidative injury was greater in the group with severe PD (protein carbonyls = 25.43 ± 11.09 fmoles/g protein) compared to the healthy group (7.77 ± 2.38 fmoles/g protein) (p<0.05). Individuals with low salivary TAA were 4.5 times more likely to suffer severe PD. TAA in males (654 ± 25 gWral/min) was significantly higher than in females (545 ± 23 pWml/min) (p=0.002), but no relationship was noted between sex and periodontal health. TAA and urate flow rates followed the same monthly cyclical pattern as progesterone and ß-estradiol in women. Nutritional antioxidant supplementation was found to have little effect on salivary antioxidant status with only a transient increase in ascorbate evident. These data suggest that severe PD is associated with a decreased salivary antioxidant flow rate and increased oxidative injury. In addition, dietary antioxidant supplementation does not appear to increase salivary antioxidant status as it does in plasma. Toothpastes and mouthrinses containing antioxidants may reduce the extent of oxidative injury in vivo, with more research required in this area.
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Marras, Stefano. "Variation inter-individuelle des performances de nage chez le loup, Dicentrarchus labrax." Montpellier 2, 2009. http://www.theses.fr/2009MON20210.
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Les poissons utilisent la nage pour accomplir des activités aussi essentielles que la prédation, la fuite, la migration, ou la recherche d'un partenaire. Bien que la nage soit attendue être vitale pour la plupart des poissons, il a été montré de fortes différences dans les performances entre individus d'une même espèce. Cette thèse s'intéresse aux variations inter-individuelles des nages aérobies et anaérobies chez le loup de mer (Dicentrarchus labrax). Plus précisément, les travaux ont évalué l'étendu de cette variation et sa répétitivité au cours du temps et ont cherché à identifier l'existence d'un compromis fonctionnelle entre les différents types de nages. La vitesse maximum de la nage aérobie s'est révélée remarquablement uniforme et répétable chez le loup, suggérant une sélection pour les individus qui peuvent constamment maintenir les fonctions aérobies à leur maximum. Au contraire, les traits de la nage anaérobie, comme la nage par à-coup, la performance de sprint et la réponse de fuite, ont tous révélés de très fortes variations inter-individuelles. La variation de la vitesse maximale de nage par à-coup semble refléter un compromis entre la performance réalisée et le temps de récupération induit par cette performance. Les variations des vitesses de sprint et des réponses de fuite étaient relativement stables et répétables mais aucune explication fonctionnelle à ces variations n'a pu être trouvée. Malgré l'attendu théorique d'une corrélation négative (compromis) entre les performances aérobies et anaérobies et d'une corrélation positive entre les différentes performances anaérobies, aucune relation claire n'a été trouvée. En l'état, il apparait difficile d'expliquer les fortes variations des performances de nage anaérobies chez le loup. Toutefois, l'existence chez cette espèce d'un cycle de vie impliquant la colonisation d'habitats contrastés (mer versus lagune) pourrait expliquer le maintient de plusieurs phénotypes de nagesFish swim to accomplish such essential activities as prey capture, avoiding predation, migrating, mating. Despite the vital nature of swimming, there is evidence that individuals of a fish species show wide variation in their ability to swim. This thesis investigated individual variation in major traits of aerobic and anaerobic swimming performance in the European sea bass (Dicentrarchus labrax); the extent to which trait variation was stable and repeatable over time, and whether the variation reflected trade-offs between different types of performance. Maximum aerobic swimming speed was remarkably uniform in the sea bass, and highly repeatable, indicating selection for individuals which can preserve maximal aerobic function at all times. By contrast, traits of anaerobic performance, such as maximum anaerobic bursting speed, maximum sprinting speed, and the fast-start escape response, all show a high degree of individual variation. Variation in maximum anaerobic bursting speed may reflect a trade-off whereby high performance requires a significantly longer recovery period. The basis for the variation in sprinting speed and escape response is unknown, although the variation was relatively stable and repeatable over time. There were no clear relationships between the different independent performance traits in the sea bass, despite the fact that a negative relationship (trade-off) between aerobic and anaerobic performance had been predicted on theoretical grounds, as had positive relationships between different types of anaerobic performance. Thus, the large degree of variation in anaerobic performance cannot be explained at present, but may reflect a life cycle of seasonal colonization of diverse habitats, where no single performance phenotype has an adaptive advantage
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Wimmer, Julia [Verfasser], and Michael [Akademischer Betreuer] Rehli. "Genetic determinants of inter-individual variations in DNA methylation / Julia Wimmer. Betreuer: Michael Rehli." Regensburg : Universitätsbibliothek Regensburg, 2016. http://d-nb.info/1100276025/34.
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Karkhanis, Teja. "Intra-animal and Inter-animal Variations in the Biomechanical Properties of Tracheal Cartilage Rings." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1448037942.
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Bui, Hong-Hai. "Analyse de la diversité inter et intra-spécifique des paramètres de l’architecture des systèmes racinaires chez les Solanacées." Thesis, Avignon, 2015. http://www.theses.fr/2015AVIG0672/document.
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Analyse de la diversité inter et intra-spécifique des paramètres de l’architecture des systèmes racinaires chez les Solanacées. Les racines des plantes jouent un rôle important pour garantir productivité et résistance à de nombreux stress. Dans le nouveau contexte agricole, l’importance de ce système racinaire et de sonarchitecture sont remises au premier plan. Notre étude porte sur la dynamique de l’architecture racinaire des solanacées, qui contient un ensemble d’espèces horticoles importantes pour l’alimentation. Notre travail porte sur 32 génotypes, parmi 3 groupes d’espèces: aubergines, piments et tomates.Dans cette étude, nous proposons tout d’abord une analyse de la diversité inter et intraspécifique de l’architecture racinaire à travers l’évaluation d’un ensemble de traits qui sont aussi les paramètres d’un modèle dynamique de simulation (ArchiSimple : Pagès et al, 2012). Cette première évaluation a été faite en pots, en utilisant un milieu très favorable à la croissance des plantes et à l’enracinement. Nous montrons que les traits racinaires choisis présentent en effet des variations d’origine génétique, généralement plus fortes entre espèces qu’au sein des espèces. Nous avons également observé des corrélations entre certains traits qui révèlent des compromis ou des coordinations dans les processus de développement.Pour aller plus loin dans la signification des traits racinaires choisis et leur stabilité vis‐à‐vis des conditions environnementales, nous avons également évalué ces traits en conditions de culture hydroponique. C’est un milieu reconnu comme radicalement différent, intéressant pour les possibilités de visualisation des racines qu’il offre. Un dispositif avec des rhizotrons hydroponiques a été construit spécifiquement pour cette expérimentation. Nous avons confirmé, dans ces nouvelles conditions, les différences d’origine génétique entre les différents génotypes utilisés. De plus, nous avons comparé de manière systématique les valeurs de traits mesurés avec celles de la précédente expérimentation. Certains traits se révèlent stables ou très corrélés (e.g. diamètres, distances interramification)alors que d’autres présentent des différences beaucoup plus fortes (e.g. vitesses de croissance, vitesses d’émergence des racines adventives).Une troisième expérimentation, utilisant différentes combinaisons de greffage entre génotypes, nous a permis d’approfondir la question du contrôle des traits par des interactions au sein de la plante: soit à courte distance au sein du système racinaire, soit à plus longue distance parle système aérien. Deux traits importants ont été étudiés (le diamètre apical et la densité de ramification) en utilisant des combinaisons de génotypes ayant des valeurs contrastées par rapport à ces traits. Il en ressort des réponses très différentes, avec un effet marqué du greffon sur les111RésuméBui H.H. (2015), Diversité inter- et intra-spécifique des paramètres racinaires chez les Solanacées diamètres, révélant qu’une partie au moins du contrôle de ce trait est effectuée par le système aérien, et un effet faible ou inexistant du greffon sur la densité de ramification, révélant un contrôle local de ce trait, par des interactions à courte distance entre les racines. Cette expérimentation par greffage a montré un potentiel très intéressant pour mettre en lumière divers mécanismes de contrôle des traits au sein de la plante entière.Cette étude mérite d’être prolongée par des analyses plus systématiques des déterminismes de variation des traits de l’architecture racinaire, et par des simulations par modèle qui permettront de synthétiser les conséquences des variations de traits sur les performances globales des systèmes racinaires pour la prospection du solAnalysis of the inter and intra specific diversity of the parameters of the root system architecture in the Solanaceae.Plant roots play an important role to ensure the productivity and the resistance to manystresses. In new agricultural context, the importance of root system and its architecture are placed tothe forefront. Our study focuses on the root architecture dynamics of Solanaceae, which contains aseries of important horticultural species for the alimentation. Our work was based on 32 genotypesbelonging to three groups of species: aubergines, capsicums, and tomatoes.In this study, we propose firstly an analysis of inter‐ and intra ‐ specific diversity of rootarchitecture through evaluating a set of traits which are also the parameters of a dynamic simulationmodel (ArchiSimple: Pagès et al, 2012). The experiment in pots with a very favorable condition forplant growth and rooting was conducted for the first evaluation. It showed that the selected roottraits present an effect of genetic ‐ originated variations and this effect is usually stronger amongspecies than within species. We also found correlations between certain traits, which revealcompromises or coordinations in the developmental processes.In order to go deeper into the signification of selected root traits and their stability toenvironmental conditions, we also evaluated these traits in hydroponic culture. This environment isradically different, and interesting for its possibilities to visualize the roots. An experimental setupwith hydroponic rhizotrons was specially built for this experiment. In the new conditions, the genetic‐ originated differences between different genotypes used also were found. In addition, wecompared systematically the traits values with those of the previous experiment. Certain traits arestable or highly correlated (e.g., apical diameter, inter‐branch distance), while others are muchdifferent (e.g., root growth rate, emission rate of adventitious roots).In a third experiment, we used different grafting combinations between genotypes todeepen the question of the control of root traits by interactions within plant: either short distancecontrol within root system or long distance control by aerial system. Two important root traits (apicaldiameter and branching density) have been studied by grafting between genotypes which havecontrasting values on these traits. The different responses appear: a significant effect of scion ondiameters, which indicate that at least of this trait is controlled by shoot system, and a weak effect orno effect of scion on branching density, revealing the local control of this trait, by short distanceinteractions between the roots. This experiment showed a great potential of grafting to highlightvarious control mechanisms of root traits within whole plant.AbstractBui H.H. (2015), Diversité inter- et intra-spécifique des paramètres racinaires chez les Solanacées 113This study deserve to be extended by more systematic analysis of determinisms of variationsof root architecture traits, and by using simulation model which allow to integrate the consequencesof traits variations on global performances of root system for prospecting of soil
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Tsampalieros, Anne. "Inter-centre Variation in the Management of Kidney Transplant Recipients and Its Impact on Clinical Outcomes." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/37266.
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Introduction: There is an increasing number of Canadians living with end stage renal disease (ESRD). Kidney transplantation is currently the best treatment for ESRD but long-term outcomes remain suboptimal. Identifying factors associated with better outcomes may lead to interventions or practice change that could improve patient survival or quality of life. The objectives of this thesis were to: i) systematically review the literature to examine centre variation in kidney transplantation outcomes and identify centre and provider level factors that may contribute to variation in outcomes; ii) describe differences that may exist at the patient, centre and provider level at the time of kidney transplantation across the six transplant centres in Ontario, Canada; iii) examine variation in graft and patient survival rates across transplant centres in Ontario; and iv) examine whether patient, centre and provider level characteristics contribute to variation in graft and survival rates across transplant centres.
Methods: The first objective of this thesis was met by conducting a systematic review of the literature according to a predefined protocol. The last three objectives of the thesis were met by conducting a population based retrospective cohort study using administrative data from Ontario. Differences at the patient, centre and provider level were described at the time of kidney transplantation. Outcomes of interest included total graft loss; graft loss with follow-up censored at death; death with graft function; and total mortality. All outcomes were assessed at one year post transplantation and at the end of study follow up. Cox proportional hazards regression was used to obtain hazard ratios (HR) for each centre relative to the average across all centres. The independent effect of centre volume and provider characteristics on outcomes was also examined.
Results: The systematic review identified 24 eligible studies. Outcomes included graft survival (n=24) and patient survival (n=9). The main characteristics evaluated were centre volume (n=17) and provider volume (n=2). Centre variation in graft survival was described in 80% (12/15) of studies, while less than half of studies (8/17) found a significant association between volume and graft survival. The population based retrospective cohort included 5092 adults (≥18 years) who received a primary solitary kidney transplant across 6 transplant centres in Ontario between January 1st 2000 and December 31st 2013. Variation in patient, centre and provider level factors existed across centres at the time of transplantation. At the end of study follow-up, case-mix adjusted HRs for total graft loss ranged from 0.84 (95% CI 0.53-1.33) to 1.16 (95% CI 1.00-1.34) across centres (p-value for between centre variation 0.46). After adjusting for centre and provider factors, differences across centres persisted. Centre volume, provider experience and provider type were not independently associated with either short or long-term outcomes (all p>0.05) with the exception of graft loss with follow-up censored at death.
Discussion: This thesis suggests that there is variation in clinical outcomes across transplant centres in Ontario which is not explained by patient factors, centre volume or provider characteristics at the time of transplantation. Additionally centre volume, provider type and experience were not independently associated with outcomes. Future prospective studies with a larger sample size of transplant centres that examine follow-up care after discharge from hospital (e.g. frequency of visits) are required to better understand this phenomenon.
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Elsey-Quirk, Tracy. "Inter- and intraspecific variation in carbon and nutrient pools of salt marsh plants." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 236 p, 2010. http://proquest.umi.com/pqdweb?did=1993336371&sid=9&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Mantiri, Feky R. "Inter- and intraspecific variation within Cylindrocarpon inferred from mitochondrial small subunit rDNA sequences." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0023/MQ51409.pdf.
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Walker, Marlene Rona. "Inter-island genetic and cultural variation in the Thick-billed Vireo (Vireo crassirostris)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq40891.pdf.
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Neary, M. G. "Assessment of the inter-individual variation observed between patients receiving HIV antiretroviral therapy." Thesis, University of Liverpool, 2018. http://livrepository.liverpool.ac.uk/3027990/.
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The WHO currently recommends tenofovir (TFV) disoproxil fumarate (TDF) or TFV alafenamide (TAF) as a preferred first-line antiretroviral therapy (ART) for the treatment and prevention of HIV. However, mild to moderate TFV-related renal toxicity is an uncommon but significant complication for TDF therapy. Efavirenz (EFV) is also approved for first line treatment, with the approval of a lower dose treatment, 600mg to 400mg, offering an opportunity for a greater number of patients to receive ART for the same amount of current public health expenditure, whilst enabling the maintenance of viral load suppression and partial mitigation of adverse events. However, EFV displays broad inter-patient and inter-population variability in its pharmacokinetics and displays a range of dose dependent adverse effects. In order to gain further understanding of the impact patient genetics has on response to ART, studies investigating the effect of single nucleotide polymorphisms (SNPs) within multi ethnic populations receiving either TFV or EFV were completed. Additional work was conducted to investigate potential drug-substrate interactions at the transporter level within proximal tubule cells (PTCs), and the ramifications this may have for diagnosis of renal impairment. This work was conducted through assessing the relationship between SNPs found within genes encoding transporters on the apical membrane of PTCs and a diagnosis of renal dysfunction, defined as kidney tubular dysfunction or chronic kidney disease within a Ghanaian population (Chapter 2). Additionally the association between pharmacogenetic variants linked to TDF metabolism or TFV excretion and TFV plasma and urine concentrations, in a majority Caucasian patient population, receiving TFV as part of their ART was investigated (Chapter 3). This thesis sought to assess whether SNPs in genes involved in EFV and nevirapine metabolism were linked to previously observed changes in the contraceptive subdermal implant levonorgestrels (LNG) pharmacokinetics, when prescribed alongside EFV, 19 within a Ugandan population (Chapter 6). In order to study the effect of transporter interactions at the site of TFV toxicity, the proximal tubule, a transiently transfected Human Embryonic Kidney 293 cell line overexpressing either multidrug and toxin extrusion protein (MATE) 1 or MATE2K was developed and assessed for correct functionality (Chapter 4). This cell line was then utilised for drug-substrate interaction studies between TAF and TFV and either the endogenous biomarker creatinine or the type 2 diabetes drug metformin (Chapter 5). These studies provided a greater understanding of the contribution pharmacogenetics provides to the interaction observed between EFV and LNG, and outlined a genetic association between TFV transporter SNPs and TFV plasma and urine concentrations. Utilisation of these findings in future pharmacogenetics studies would aid in the understanding of the impact of genetic variants in different populations, and the consequences this has for achieving sustained virological response to ART. The study of the effect of TAF and TFV on MATE1 and MATE2K transport of metformin and creatinine produced novel data on these interactions. Overall, the studies included within this thesis have clinical impact through further elucidating the potential mechanisms of toxicity or treatment failure within patients receiving ART.
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Germain, Ryan Ross. "The effects of habitat preference, environmental heterogeneity, and inter-individual variation on fitness." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54978.
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Theory predicts that animals breeding in heterogeneous landscapes should select habitat likely to maximize individual fitness, but identifying the fine-scale environmental characteristics which influence habitat preference and affect fitness is often problematic. While many studies quantify relationships between habitat preference and the reproductive success of their occupants, few are able to separate the independent effects of inter-individual variation among animals in a population from the effects of habitat on indices of fitness. In this thesis, I used up to 39 years of nesting, survival, and pedigree data from a resident, island population of song sparrows (Melospiza melodia) to identify fine-scale environmental characteristics which influenced habitat preference, determine whether preferred habitats positively affected fitness, and distinguish the relative effects of preferred habitats on indices of fitness from those due to inter-individual variation among song sparrows within the population. Song sparrows in this population exhibited marked preference for habitats that conferred positive effects on individual fitness via annual reproductive success and survival. Females nesting in preferred habitats also began breeding earlier, exhibited more energetically efficient incubation behaviour, and produced more offspring that recruited the population than those nesting in less-preferred sites. Preferred habitats in this system had more shrub cover, more edge, and deeper soil. The potential benefits of occupying preferred habitats included greater early season food availability and shelter from predators and inclement weather during both the breeding and non-breeding seasons.
Despite the positive effects of preferred habitats on fitness, the relative contributions of habitat to indices of fitness were substantially less than those related to inter-individual variation in phenotype, genotype and developmental stage (measured as relative lifetime reproductive success, additive genetic and permanent individual variance, and age). Together, results from this thesis suggest that inter-individual variation in ‘quality’ can be more influential of fitness than habitat quality in free-living populations, and highlight the importance of estimating the relative contributions of inter-individual variation when attempting to identify the environmental correlates of fitness in natural systems.Forestry, Faculty of
Graduate
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Kural, Deniz. "Methods for Inter- and Intra-Species Genomics for the Detection of Variation and Function." Thesis, Boston College, 2014. http://hdl.handle.net/2345/bc-ir:104053.
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Thesis advisor: Gabor T. MarthThis thesis concerns itself with the development of methods for comparing genomes. Chapter 2 is a comparative genomics investigation of coding regions across multiple species. Regions of the genome coding for proteins show higher conservation than non-coding regions. Furthermore, we show that a portion of coding regions are conserved beyond the requirements of protein conservation, supporting functions such as microRNA binding and splicing enhancement, providing the non-coding functional impetus to conservation. In Chapter 3, we focus on the detection and characterization of a particular type of structural variation - mobile element insertions (MEIs). While there are many types of mobile elements in the human genome, three of these are active and cause most of the MEI variation observed in humans: ALU, L1 and SVA elements. We detect variation across 1000 Genomes Pilot populations caused by these elements, assemble ALU elements to single nucleotide resolution, and determine actively copying species of this element. We've developed a variety of algorithmic approaches to MEI detection, and present these. Chapter 4 outlines an approach to remedy reference bias via the incorporation of variation data into the reference. In particular, we construct a pan-genome reference, demonstrated concretely via resolving ALU regions, and develop new alignment software to align against this enriched reference structure
Thesis (PhD) — Boston College, 2014
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Biology
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Rønning, Bernt. "Sources of inter- and intra-individual variation in basal metabolic rate in the zebra finch, : Sources of inter- and Taeniopygia guttata." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for biologi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2295.
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Saclier, Nathanaëlle. "Origine des variations de taux d’évolution moléculaire inter-spécifiques : apport d’un modèle génomique en milieu souterrain." Thesis, Lyon, 2019. https://n2t.net/ark:/47881/m69p310z.
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La vitesse à laquelle les séquences d’ADN évoluent varie selon les espèces. Ces différences peuvent venir de caractéristiques intrinsèques de l’espèce (taux métabolique, traits d’histoire de vie) ou de son environnement (rayonnements ionisants). L’objectif de cette thèse est de tester les principales hypothèses expliquant les variations de taux d’évolution moléculaire entre les espèces. Pour cela, les particularités des Asellidae souterrains ont été couplées avec des données de séquençage nouvelle génération dans le génome nucléaire et le génome mitochondrial. L’utilisation des Asellidae comme modèle biologique nous permet d’avoir, au sein du même groupe, des espèces ayant indépendamment effectuées une transition vers le milieu souterrain. Cette transition étant accompagnée de nombreux changements, tant biologiques (longévité, taux métabolique, temps de génération) qu’environnementaux, elle nous permet, au sein du même groupe, de pouvoir comparer des espèces contrastées en termes de longévité, de taille de populations, de rayonnements ionisants ou encore de productivité et de température. De plus, parce que ces organismes dispersent peu, ils persistent dans le même environnement durant de nombreuses générations, permettant de préciser et de quantifier les facteurs responsables de variations du taux d’évolution moléculaire entre les espèces.Cette approche nous a permis de mettre en évidence un effet du temps de génération sur le taux d’évolution du génome nucléaire mais pas sur le génome mitochondrial. Un effet de la radioactivité naturelle, d’une ampleur analogue à celle du temps de génération a également été mis en évidence. Enfin, l’étude des variations des taux d’évolution moléculaire à une échelle globale a révélée des biais dans les calculs des taux de substitutions qui devront être pris en compte dans les études cherchant a établir le lien entre le taux de mutations et la diversificationThe rate at which DNA accumulates substitutions varies widely among species. Rate variations have been imputed to species intrinsic features (metabolic rate, life history traits) or to the environment characteristics (ionizing radiations, selection pressure). The aim of this PhD project was to investigate the main hypotheses explaining variations in the rate of molecular evolution between species. To achieve that, we combined the unique properties of subterranean isopods from the Asellidae family and high-throughput sequencing data from the nuclear and mitochondrial genome. Asellidae species have made multiple independent transitions to subterranean environments where subterranean species have repeatedly evolved a lower metabolic rate, a longer lifespan and a longer generation time. Moreover, because they are poor dispersers, they are exposed to the same environment across many generations, allowing us to compare species with long-term contrasted features in term of life history traits and environmental characteristics. We found that generation time negatively impact the rate of molecular evolution in the nuclear genome whereas the mitochondrial rate remained unchanged. We also found an increase of the mutation rate for species living in naturally highly radioactive environments. Finally, the study of the rate of molecular evolution variation at a global scale brought forward a systematic bias which needs to be taken into account in studying the link between the mutation rate and diversification
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Jongepier, Evelien [Verfasser]. "Inter- and intraspecific variation in the host defence portfolios of Temnothorax ants / Evelien Jongepier." Mainz : Universitätsbibliothek der Johannes Gutenberg-Universität Mainz, 2016. http://d-nb.info/1225296420/34.
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Isden, Jessica Rose. "Why can't all males be attractive? : inter-individual variation in male spotted bowerbird display." Thesis, University of Exeter, 2014. http://hdl.handle.net/10871/15067.
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One of the greatest conundrums facing evolutionary biologists is how variation between individuals is maintained in situations where there is expected to be strong directional selection on an elaborate male trait. Sexual selection via female choice leads to the evolution of elaborate male traits, and consensus among females in their mate choice decisions can result in high reproductive skew. Such strong directional selection pressure may be expected to reduce genetic variation over time, yet high levels of inter-individual variation sustain such preferences. In this thesis I explored potential mechanisms that may maintain variation between individuals in one of the most unusual and exaggerated avian male traits; the bowers displayed by male spotted bowerbirds, Ptilonorhynchus maculatus. Choosy females exert strong selection pressure on males, yet males vary widely in their ability to exhibit a high quality display. My results showed that male bower owners were remarkably consistent in their display of decorations, a trait expected to experience a high level of fluctuation due to variation in the ecological and social environment. Given the range of factors that may introduce inconsistency, my results suggest that males actively maintain consistent displays, although I found no evidence for the adaptive benefits of doing so. I then explored three mechanisms that may be expected to maintain variation in bowerbird display. I found that attending the bower imposed physical costs on males, but these costs were only apparent in seasons of environmental stress. Males varied in their cognitive and problem-solving abilities, but I found no impact of higher cognitive performance on a male’s reproductive fitness. The final mechanism I tested was the impact of the social environment on male mating success. I found that males actively engage in marauding, a form of intrasexual competition targeting the bowers of rival males. Marauding was highly targeted and non-random within the population, and predominantly occurred between neighbouring bower owners. However, I was unable to determine what factors predicted these non-random interactions, and found no impact of the marauding rates experienced on male mating success. In the final part of this study, I looked at the novel occurrence of collaborative display between male bower owners and other non-bower-owning males. I found that these auxiliary males may gain delayed benefits from attending the bowers of experienced males, but was unable to determine what impact contributions from auxiliaries had on bower owning males and females attempting to assess them. I conclude by discussing the implications of my results for models of sexual selection.
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Haj, Youssef Moustafa. "The effects of inter- and intra-cultural variations on managerial discretion and the implications for national competitiveness." Thesis, University of Westminster, 2017. https://westminsterresearch.westminster.ac.uk/item/q10x2/the-effects-of-inter-and-intra-cultural-variations-on-managerial-discretion-and-the-implications-for-national-competitiveness.
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This thesis examines cross-cultural differences in managerial discretion and the extent to which variations in inter- and intra-cultural practices affect the degree of freedom in decision-making that is afforded to executives. Research into the degree of discretion, or ‘latitude’ of executive action, has primarily focused on individual-, firm-, and industry-level factors which, either enable or otherwise constrain the freedom of executive action. However, research into its national-level antecedents and consequences remains limited. This thesis further develops and extends the extant literature into the topic of managerial discretion by seeking to adopt a broader interpretation of national culture in relation to its effect on executive discretion across 18 countries from 6 different regional clusters. The research entails a quantitative assessment to examine the relationship between cultural practices, managerial discretion and national competitiveness. The investigation into the national-level antecedents, consequences and the role of managerial discretion is studied using a mixture of primary and secondary data. Primary data consists of measurements of the degree of managerial discretion that is derived from survey responses of a panel of senior management consultants, who provided 792 discretion scores for the sampled countries. Secondary data consists of cultural practices derived from GLOBE cross-cultural project and national competitiveness scores operationalized using the Global Competitiveness Index (GCI). The thesis presents three empirical analyses of socio-cultural dynamics. The research first addresses how cross-national variations in cultural practices impact managerial discretion. The findings reveal that institutional collectivism, uncertainty avoidance, power distance, future-, humane-, and performance orientations, together with gender egalitarianism, assertiveness and cultural looseness, all influence the degree of discretion. In the second dimension, the notion that intra-cultural variation plays a crucial role in shaping managerial discretion is critically discussed. An empirical analysis supports such a proposition and demonstrates a strong and positive association between these two constructs. For the third aspect, the relationship between managerial discretion and national performance is measured and evaluated by determining the impact upon national competitiveness. The data demonstrate that the degree of discretion directly influences national competitiveness and effectively mediates the relationship between cultural practices and national competitiveness. Overall, this PhD contributes to the field of strategic management, by discovering for the first time new national-level antecedents and consequences of managerial discretion, offering new theoretical insights and practical implications.
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Joswig, Marc [Verfasser]. "Inter-/ intrafraktionelle Variationen und dosimetrische Auswirkungen bei der Bestrahlung von Prostatakarzinomen / Marc Joswig." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2016. http://d-nb.info/1113592664/34.
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Richard, Quentin. "Hétérogénéité individuelle, variabilité temporelle et structure spatiale comme sources de variation démographique chez les grands herbivores de montagne." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAV070/document.
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Dans l’hémisphère Nord, les populations de grands herbivores ont connu ces dernières décennies des modifications environnementales majeures, liées d’une part à l’augmentation importante de leur densité, et d’autre part aux changements globaux qui affectent leur habitat (notamment réchauffement climatique, modification des activités humaines, et fragmentation de l’habitat). Mieux comprendre comment ces espèces vont adapter leurs stratégies d’histoire de vie pour répondre à ces modifications est une question majeure de l’écologie des populations, et une étape nécessaire pour pouvoir adapter leur gestion aux enjeux environnementaux et sociétaux actuels. C’est dans ce contexte que nous avons étudié quelles étaient les sources de variation des tactiques de survie et de reproduction chez trois espèces de grands herbivores de montagne (l’isard Rupicapra pyreneica, le chamois Rupicapra rupicapra, et le mouflon méditerranéen Ovis gmelini musimon × Ovis sp.). A partir de suivis longitudinaux par capture-marquage-recapture (CMR) nous nous sommes plus particulièrement focalisés sur le rôle de l’hétérogénéité individuelle latente, de la variabilité climatique et de la structuration spatiale sur les paramètres démographiques.Ce travail s’est appuyé sur l’utilisation de modèles de mélange et d’une combinaison innovante du robust-design et des modèles multi-événements pour analyser des données démographiques collectées à différentes échelles spatio-temporelles. L’hétérogénéité individuelle s’est avérée être une composante majeure de la démographie des 3 espèces étudiées, avec l’identification chez le mouflon et l’isard de femelles aux performances reproductives contrastées, et l’existence chez le chamois de différences de survie entre individus liées à la qualité de l‘habitat occupé. Ces modèles ont aussi permis de révéler une augmentation de l’investissement reproducteur en fin de vie chez les femelles de mouflon au détriment de leur survie et d’étudier chez les femelles d’isard les différentes phases de l’effort reproducteur, de la gestation au sevrage, pour mettre en évidence que seule la lactation a un coût sur la reproduction suivante. Nos résultats ont également mis en exergue le rôle prépondérant du climat hivernal et printanier sur les paramètres démographiques des 3 espèces, tout en confirmant que ces effets sont souvent spécifiques à la population et au site étudiés. Cette étude montre également que l’isard et le mouflon, bien que relativement comparables en termes de taille, de traits écologiques, et de position phylogénétique, adoptent des stratégies d’histoire de vie contrastées.Au final, nos résultats soulignent donc l’importance des études démographiques comparatives à plusieurs niveaux d’organisation (inter-espèces, inter-population, intra-population), pour mieux comprendre le devenir des espèces de grands herbivores face aux perturbations environnementalesIn Northern hemisphere, populations of large herbivores have to cope with major environmental modifications linked to the increase of their density and to global change which strongly impacts their habitat (climate change, modification of human activities and habitat fragmentation). Understanding how these species adjust their life history strategies in response to such modifications is central for population ecology and for management issues. In this context, this work aimed to identify the sources of variation of survival and reproductive tactics in 3 species of mountain ungulate (Pyrenean chamois Rupicapra pyreneica, Alpine chamois Rupicapra rupicapra, and Mediterranean mouflon Ovis gmelini musimon × Ovis sp.). Using capture-mark-recapture monitoring we specifically investigated the role of individual heterogeneity, climate change, and spatial heterogeneity in shaping vital rates.This work relied on mixture models and an innovative combination of robust-design into a multi-events framework to explore demographic data collected at different spatio-temporal scales. Fixed heterogeneity appeared as a major demographic component in the 3 studied species by highlighting in mouflon and Pyrenean chamois two groups of females with contrasted reproductive performance, and by providing evidence in chamois of among-females differences in survival rates linked to the quality of their habitat. These models allowed us to provide evidence for the terminal investment hypothesis in female mouflon and to decompose reproductive effort in females of Pyrenean chamois from gestation to weaning, to unveil that lactation only led to cost on subsequent reproduction. Our results also highlighted the major influence of winter and spring climatic conditions on demographic parameters in the 3 studied species, and confirmed the general trend that climate effects are often species- and site-specific. Our findings provided evidence that Pyrenean chamois and mouflon evolved contrasted life history strategies, although both species share strong similarities in terms of body mass, ecological traits and phylogenetic position.Finally, our work stresses the importance of conducting comparative demographic studies, based on longitudinal monitoring of marked individuals, at inter-specific, inter-population and within population levels, to better understand and predict the future of large herbivores populations in the current context of global changes
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Schulz, Aretha Rodrigues. "Variações inter-individuais em biomarcadores de exposição ao mercúrio em uma população ribeirinha do rio Tapajós, Pará." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/60/60134/tde-22072009-160630/.
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O mercúrio (Hg) é um metal tóxico extensamente estudado em todo mundo, distribuído no ambiente a partir de fontes naturais ou antropogênicas e que oferece risco a população por ser altamente biocumulativo e possuir efeitos nocivos à saúde. Até algum tempo atrás, acreditava-se que a principal fonte de exposição ao Hg na Região Amazônica, decorria do uso deste metal para amalgamação de ouro nos garimpos da região. No entanto, o Hg é encontrado naturalmente nos solos da Região Amazônica e ao atingir os sistemas aquáticos, favorecidos principalmente pela erosão e pelas chuvas, passa por um processo de metilação catalisada por microorganismos, dando origem à forma orgânica do metal, o metilmercúrio (MeHg). Esta forma do metal se acumula no sedimento dos rios e em peixes representando atualmente a principal fonte de exposição ao mercúrio em população ribeirinha. Os biomarcadores de exposição ao Hg são freqüentemente utilizados para identificar e estimar o risco em que um indivíduo ou uma população está exposta. No entanto, pouco se conhece a respeito das variações inter-individuais de cada um deles. Neste sentido, este estudo teve como objetivo avaliar as variações inter-individuais em biomarcadores de exposição ao Hg em uma população ribeirinha do rio Tapajós, Pará. Para tal, 410 ribeirinhos, residentes em 12 comunidades ao longo do rio Tapajós, no estado do Pará participaram do estudo. Foram determinadas as concentrações de mercúrio total (THg) em sangue total, plasma, eritrócito, urina e de IHg e MeHg em cabelo dos voluntários. As concentrações de THg no sangue total variaram de 1,7 a 288,9 µg/L e no plasma de 0,2 a 40,0 µg/L. A concentração de THg no plasma apresentou uma alta correlação com as concentrações de THg em sangue total (r=0,7529, p<0,0001). A fração plasmática de THg variou 0,5% a 61% e não apresentou qualquer correlação com as concentrações de THg em sangue total (r= 0,06284, p=0,2041), indicando que a mobilização de THg para o plasma não ocorre devido à saturação dos eritrócitos. A distribuição de THg entre eritrócitos e plasma observada nesta população, é diferente do que foi observado em outros estudos sobre exposição à MeHg. As concentrações de THg no cabelo variaram de 0,97 a 62,4 µg/g e apresentaram uma correlação muito forte com as concentraçoes no sangue (r=0,8718, p<0,0001) indicando que as concentrações de THg no cabelo refletem as concentrações de THg no sangue. Também foi observada uma forte correlação entre as concentrações de MeHg e de IHg no cabelo (r=0,8979, p<0,0001), confirmando as informações da literatura, que sugerem que a fração de IHg no cabelo se deve a demetilação no sangue, no folículo capilar ou no preparo da amostra e análise. Em relação a razão entre concentração de mercúrio entre cabelo e sangue, observamos uma elevada variação entre os indivíduos, de 1:13 a 1:13274. Entre as mulheres observamos que esta variação ocorre de acordo com a idade. Resultados preliminares apontam para uma considerável variação inter-individual nos biomarcadores de exposição na população em estudo, indicando a necessidade de se identificar os fatores que influenciam este achado. Considerando a cinética do mercúrio, podemos concluir que estas variações inter-individuais na fração plasmática, podem alterar a taxa de eliminação do Hg e também os efeitos tóxicos decorrentes da exposição. Palavras- Chave: biomarcadores de exposição, mercúrio, variações inter-individuaisMercury (Hg) is a toxic metal widely studied worldwide. In the atmosphere Hg may occur due to natural or anthropogenic sources. It offers risk to the population due to be highly bioaccumulated and to cause harmful effects to humans. Gold Mining activities were considered in the past the main sources of Hg contamination in the Amazon region. However, new findings indicated that Hg is naturally found in the soils of the Amazon area. When reaching the aquatic systems, facilitated mainly by the erosion and for the rains, the inorganic mercury is methylated, by microorganisms, forming the more toxic form methylmercury (MeHg). This form of the metal accumulates in the sediment of the rivers and in fish, meaning the main exposure source of mercury to riverine population. Biomarkers of exposure to Hg (levels of Hg in blood, plasma, urine, hair) are frequently used to identify and to esteem the risk of an individual or a population to harmful effects. However, little it is known regarding the inter-individual variations of these biomarkers. In this sense, this study evaluated inter-individual variations in the biomarkers of exposure to mercury (Hg in plasma, blood, urine and hair) in a riverside population (Tapajós river, Pará). Volunteers (n=410), residents in 12 communities along the Tapajós river, in the state of Pará participated in the study. Total mercury (THg) levels were determinated in whole blood, plasma, red blood cells and urine and of IHg and MeHg in hair. The concentration of mercury ranged from 1.7 to 288.9 µg/L and of plasma from 0.2 to 40.0 µg/L. The concentration of THg in the plasma presented a high correlation with concentrations of Hg in total blood (r=0.7529, p<0.0001). The plasmatic fraction of THg ranged from 0.5% to 61% and did not present any correlation with the concentrations of THg in the whole blood (r= 0.06284 p=0.2041), indicating that the mobilization of Hg to the plasma does not occur to the saturation of the red blood cells. The distribution of THg between red blood cells and plasma observed in this population is in disagreement when compared to other populations. The mercury concentrations in hair ranged from 0.97 to 62.4 µg/g and presented a very strong correlation with the whole blood (r=0.8718, p<0.0001), indicating that the concentrations of Hg in hair reflect the concentrations of THg in blood. Also a strong correlation was observed among the concentrations of MeHg and of IHg in hair (r=0.8979, p<0.0001), confirming the information in the literature, that suggest the fraction of IHg in hair is due to demethylation process or by sample preparation and analysis. Regarding the ratio between concentration of mercury between hair and blood, we observed a high variation between individuals, ranged from 1:13 to 1:13274. Among the women we observed this variation occurring according to age. In conclusion our results together demonstrated a considerable inter-individual variation in the biomarkers of exposure to mercury in the study population, demonstrating probably a different rate of biotransformation and elimination of Hg in this population. Then, future studies are necessary to elucidate factors are influencing this variation.
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Josefsson, Jonas. "The Many Phases of Phenology : Geographic and Inter-Specific Differences in Phenological Between-Year Variation." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-154493.
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As climate-driven changes in phenology are becoming more apparent, the need to quantify these changes is increasing. An important challenge in detecting phenological changes is that between-year variation in phenology is large. Between-year variation determines the statistical power of comparisons between contemporary and historical observations. For 44 plant species with different distributions across Sweden, geographicand inter-specific differences in between-year variation in different phenophases (budburst, flowering, ripe fruits, and leaf fall) was studied. I also modeled and evaluated theresponse of bud burst, and flowering, to temperature using three different temperature sum models over a latitudinal gradient. The data used was a sub-sample from a dataset collected by a Swedish nation-wide phenology network between 1873-1917. In agreement with previous studies, I show that early spring phases have a higher variability than phases occurring later in the season. However, the relation between onset and variation was not monotonically decreasing. In the geographical analyses, a unimodal relation between between-year variation and latitude was found, that is, the between-year variation decreased along the latitudinal gradient for early- and late season events, while it increased over latitude for summer events. These patterns are, to a great extent, reflections of patterns in air temperatures which is discussed using meteorological data from adjacent climate stations. Models were evaluated using Akaike's Information Criterion, and in 60% of all fits, the Spring warming CF2 model (SWCF2; the model with the least number of parameters) was selected as the best model to describe the data. For Sorbus aucuparia bud burst, in the two parameter model SWCF2, both parameters (threshold temperature andtemperature sum) correlated with latitude. However, future analysis using more locations and a wider span of species will be needed to understand the generality in these findings. In conclusion, future efforts to detect and quantify phenological changes need to consider differences in between-year phenological variability along geographical gradients and among species with different phenology.
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Farhat, Imen, and Imen Farhat. "Inter-provider variation in resource use intensity for elderly injury admissions : a multicenter cohort study." Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/38114.
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Les aînés (≥65 ans) représentent une proportion grandissante des admissions pour traumatismes. Cependant, on connait peu sur leur utilisation des ressources hospitalières. Pour améliorer les connaissances sur l’utilisation des ressources, nos objectifs étaient d’identifier les déterminants de l’utilisation des ressources, étudier la variation inter-hospitalière et évaluer l’association avec les résultats cliniques. Nous avons réalisé une étude de cohorte multicentrique en incluant tous les aînés admis dans le système de traumatologie du Québec (2013-2016) avec blessures traumatiques (N=16463) et avec fractures de fragilité (N=16721). Nous avons estimé l’utilisation des ressources avec la méthode de coûts basés sur les centres d’activité. Nous avons utilisé des modèles linéaires et logistiques multiniveaux pour nos analyses. L’utilisation des ressources augmentait avec l’âge et le nombre de comorbidités. La destination à la sortie de l’hôpital était aussi un important déterminant (soins longue durée vs domicile; blessures traumatiques; ratio de moyennes géométriques [RMG]=1,68; IC 95%=1,61-1,75; fracture de fragilité; RMG=1,28 IC 95%=1,24-1,32). L’utilisation des ressources ajustée variait significativement entre les hôpitaux. Cette variation était plus importante chez les patients avec des fractures de fragilité (coefficient de corrélation interclasse [CCI]=0,093; IC 95%=0,079-0,102) que chez ceux avec des blessures traumatiques (CCI=0,047; IC 95%=0,037-0,051). Les hôpitaux avec une plus importante utilisation des ressources avaient tendance à avoir une incidence plus élevée de mortalité (fracture de fragilité : coefficients de corrélation de Pearson [r]=0,41; IC 95%=-0,16-0,60) et de complications (blessures traumatiques : r=0,55; IC 95%=0,33-0,71; fracture de fragilité : r=0,54; IC 95%=0,32-0,70). Nos résultats suggèrent qu’il y a place à l’optimisation des ressources pour les aînés admis pour blessures. L’augmentation de mortalité et morbidité dans les hôpitaux utilisant plus de ressources pourrait être expliquée par la confondance résiduelle mais aussi par les effets indésirables reliés aux interventions ou aux journées d’hospitalisation potentiellement non-nécessaires. Ces hypothèses seront à confirmer lors d’études futures.Les aînés (≥65 ans) représentent une proportion grandissante des admissions pour traumatismes. Cependant, on connait peu sur leur utilisation des ressources hospitalières. Pour améliorer les connaissances sur l’utilisation des ressources, nos objectifs étaient d’identifier les déterminants de l’utilisation des ressources, étudier la variation inter-hospitalière et évaluer l’association avec les résultats cliniques. Nous avons réalisé une étude de cohorte multicentrique en incluant tous les aînés admis dans le système de traumatologie du Québec (2013-2016) avec blessures traumatiques (N=16463) et avec fractures de fragilité (N=16721). Nous avons estimé l’utilisation des ressources avec la méthode de coûts basés sur les centres d’activité. Nous avons utilisé des modèles linéaires et logistiques multiniveaux pour nos analyses. L’utilisation des ressources augmentait avec l’âge et le nombre de comorbidités. La destination à la sortie de l’hôpital était aussi un important déterminant (soins longue durée vs domicile; blessures traumatiques; ratio de moyennes géométriques [RMG]=1,68; IC 95%=1,61-1,75; fracture de fragilité; RMG=1,28 IC 95%=1,24-1,32). L’utilisation des ressources ajustée variait significativement entre les hôpitaux. Cette variation était plus importante chez les patients avec des fractures de fragilité (coefficient de corrélation interclasse [CCI]=0,093; IC 95%=0,079-0,102) que chez ceux avec des blessures traumatiques (CCI=0,047; IC 95%=0,037-0,051). Les hôpitaux avec une plus importante utilisation des ressources avaient tendance à avoir une incidence plus élevée de mortalité (fracture de fragilité : coefficients de corrélation de Pearson [r]=0,41; IC 95%=-0,16-0,60) et de complications (blessures traumatiques : r=0,55; IC 95%=0,33-0,71; fracture de fragilité : r=0,54; IC 95%=0,32-0,70). Nos résultats suggèrent qu’il y a place à l’optimisation des ressources pour les aînés admis pour blessures. L’augmentation de mortalité et morbidité dans les hôpitaux utilisant plus de ressources pourrait être expliquée par la confondance résiduelle mais aussi par les effets indésirables reliés aux interventions ou aux journées d’hospitalisation potentiellement non-nécessaires. Ces hypothèses seront à confirmer lors d’études futures.
Elderly trauma admissions are increasing exponentially. However, little is known about resource use for this population. To advance knowledge on resource use and its optimization, our objectives were to identify resource use determinants, assess inter-hospital variation in resource use, and examine the impact of hospital resource use on patient outcomes for elderly injured patients. We conducted a multicenter cohort study of elders (≥65 years) with trauma (N=16,463) and with fragility fractures (N=16,721) admitted in the Québec trauma system (2013-2016). We estimated resource use with activity-based costing. We used intraclass correlation coefficients (ICC) to examine inter-hospital variation in resource use, multilevel linear models to identify determinants, and Pearson correlation coefficients (r) to assess the impact of resource use on patient outcomes. Resource use increased with age and the number of comorbidities for both groups. Patients discharged to long-term care had higher resource use than those discharged home (geometric mean ratio [GMR]=1.68; 95% CI [1.61, 1.75] for trauma and GMR=1.28; 95% CI [1.24, 1.32] for fragility fractures). Risk-adjusted resource use varied significantly across trauma centers for elderly patients. There was greater variation for elders with fragility fractures (ICC=0.093; 95% CI [0.079, 0.102]) than with trauma (ICC=0.047; 95% CI [0.035, 0.051]). Trauma centers with higher risk-adjusted resource use tended to have a higher incidence of mortality (r=0.41; 95% CI [0.16, 0.60]) for fragility fractures and complications for trauma (r=0.55; 95% CI [0.33, 0.71]) and for fragility (r=0.54; 95% CI [0.32, 0.70]). Our results suggest that there is room for resource use optimisation for elders admitted for injuries. The observed increase in mortality and morbidity in hospitals with higher resource use might be due to residual confounding but could also be due to adverse effects of potentially unnecessary interventions and hospitals stays. These hypotheses need to be confirmed in future studies.
Elderly trauma admissions are increasing exponentially. However, little is known about resource use for this population. To advance knowledge on resource use and its optimization, our objectives were to identify resource use determinants, assess inter-hospital variation in resource use, and examine the impact of hospital resource use on patient outcomes for elderly injured patients. We conducted a multicenter cohort study of elders (≥65 years) with trauma (N=16,463) and with fragility fractures (N=16,721) admitted in the Québec trauma system (2013-2016). We estimated resource use with activity-based costing. We used intraclass correlation coefficients (ICC) to examine inter-hospital variation in resource use, multilevel linear models to identify determinants, and Pearson correlation coefficients (r) to assess the impact of resource use on patient outcomes. Resource use increased with age and the number of comorbidities for both groups. Patients discharged to long-term care had higher resource use than those discharged home (geometric mean ratio [GMR]=1.68; 95% CI [1.61, 1.75] for trauma and GMR=1.28; 95% CI [1.24, 1.32] for fragility fractures). Risk-adjusted resource use varied significantly across trauma centers for elderly patients. There was greater variation for elders with fragility fractures (ICC=0.093; 95% CI [0.079, 0.102]) than with trauma (ICC=0.047; 95% CI [0.035, 0.051]). Trauma centers with higher risk-adjusted resource use tended to have a higher incidence of mortality (r=0.41; 95% CI [0.16, 0.60]) for fragility fractures and complications for trauma (r=0.55; 95% CI [0.33, 0.71]) and for fragility (r=0.54; 95% CI [0.32, 0.70]). Our results suggest that there is room for resource use optimisation for elders admitted for injuries. The observed increase in mortality and morbidity in hospitals with higher resource use might be due to residual confounding but could also be due to adverse effects of potentially unnecessary interventions and hospitals stays. These hypotheses need to be confirmed in future studies.
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Bois, Géraldine. "Les écrivains dominés du jeu littéraire : définition de l’espace d’investissement et rapports aux enjeux littéraires." Thesis, Lyon 2, 2009. http://www.theses.fr/2009LYO20085.
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Notre recherche porte sur des écrivains très peu reconnus de Rhône-Alpes (i.e. publiés chez de petits éditeurs régionaux sans légitimité littéraire, à compte d’auteur ou en autoédition). Elle s’attache à décrire et à expliquer leur investissement dans les différentes dimensions de l’activité littéraire (l’écriture, la publication, les activités publiques, etc.). Elle repose principalement sur une enquête par questionnaires auprès de 503 écrivains, répartis en plusieurs degrés de reconnaissance (les « très peu reconnus » forment une sous-population de 163 enquêtés), et sur des entretiens approfondis avec 31 auteurs très peu reconnus. À partir de l’objectivation de leurs modes d’existence littéraire (lieux d’édition et de visibilité, genres publiés, etc.), de leurs ressources extra-littéraires (position et origines sociales, niveau de diplôme, etc.), et de leurs niveaux de compétences et d’ambitions littéraires, notre analyse montre dans un premier temps que ces auteurs ne sont pas des « amateurs » évoluant dans un espace différent de celui des « professionnels », mais des membres dominés du jeu littéraire, au même titre (mais pas au même niveau) que les écrivains reconnus. Elle s’intéresse ensuite à la pluralité des degrés et des formes de leurs investissements dans cinq types d’enjeux littéraires différents, et elle met au jour des variations intra-individuelles en fonction des types d’enjeux considérés. Parce que l’engagement des enquêtés révèle des degrés de reconnaissance et de connaissance des manières légitimes de jouer au jeu littéraire, notre travail est aussi l’occasion d’une réflexion sur les rapports que des acteurs dominés entretiennent à la dominationOur research is about Rhône-Alpes writers with low recognition (i.e. published by little regional publishing houses without literary legitimacy, with the author’s financial participation, or privately printed). It aims to describe and to explain their investment in the different dimensions of literary activity (writing, publishing, public activities, etc.). It is based mainly on a survey by questionnaires answered by 503 writers, analysed in their various degrees of recognition (those with “low recognition” form a subpopulation of 163 respondants), and on in-depth interviews with 31 authors with low recognition. From the objectivation of their literary ways of existing (places of publishing and of visibility, published genres, etc.), of their extra-literary resources (social position and origins, level of qualification, etc.), and of theirs levels of literary competences and ambitions, our analysis shows that these authors are not “amateurs” playing in a space different from the “professional” one, but dominated members of the literary game, in the same way (but not at the same level) as the recognized writers. Then, it focuses on the plurality of degrees and forms of their investments in five kinds of literary stakes, and it uncovers intra-individual variations according to the kinds of stakes which are studied. Given that the investigated authors’ involvement reveals degrees of recognition and knowledge of legitimate ways of playing the literary game, our work is also an opportunity to rethink the relations that dominated actors have with domination
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Campbell, Janis Moore. "Theme & Variations: a content analysis of syllabi in introduction to urban education courses." Diss., Temple University Libraries, 2016. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/383503.
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Educational PsychologyPh.D.
This qualitative study examines the teaching of urban education in introductory and foundational college courses. The research positions course syllabi as ubiquitous public documents that socialize students into discourse communities, and is framed within theories of social constructivism. An examination of course objectives, course assignments, and core required texts revealed varying levels of consistency in the stated learning outcomes on all (n = 31) syllabi. Overall, five conceptual approaches to introductory courses in urban education emerged: 1) schools and the social order; 2) historical perspective; 3) education policy analysis; 4) professional practice, pedagogy and research persona; and 5) teacher as change agent. Shared organizing features of all syllabi included references to education inequity, social stratification, structural racism, poverty, and social justice; however, the degree of topic emphasis varied substantially. Closer alignment between course objectives and course assignments was identified in two conceptual frameworks: a) schools and the social order and b) education policy analysis. However, minimal alignment between course objectives and assignments was identified on syllabi in c) professional practice, pedagogy; d) teacher as change agent; and e) historical perspective approaches. A review of core texts on the syllabi revealed notable consensus about required titles. Urban education is a field of study inhabited by many different academic disciplines. These findings suggest that for the field’s introductory courses, greater coherence of conceptual approaches and closer alignment of assignments with objectives deserve to be carefully considered.
Temple University--Theses
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Rösner, Ralph [Verfasser], and Dörthe C. [Akademischer Betreuer] Müller-Navarra. "Response of plankton dynamics to inter-annual climatic variations and trends / Ralph Rösner. Betreuer: Dörthe C. Müller-Navarra." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2014. http://d-nb.info/1046940066/34.
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