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Eriksson, Jens. "Evaluation of Hardware Test Methods for VLSI Systems." Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-239.
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The increasing complexity and decreasing technology feature sizes of electronic designs has caused the challenge of testing to grow over the last decades. The purpose of this thesis was to evaluate different hardware test methods/approaches based on their applicability in a complex SoC design. Among the aspects that were investigated are test implementation effort, test efficiency and the performance penalties implicated by the test.
This report starts out by presenting a general introduction to the basics of hardware testing. It then moves on to review available standards and methodologies. In the end one of the more interesting methods is investigated through a case study. The method that was chosen for the case study has been implemented on a DSP, and is rather new and not as prolific as many of the standards discussed in the report. This type of method appears to show promising results when compared to more traditional ones.
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Yeary, Amber J. "Cetyltrimethylammonium Halide-Coated Electrodes for the Detection of Dopamine in the Presence of Interferents." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1323471405.
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Hedin, Niklas. "NMR studies of complex fluids and solids formed by surfactants." Doctoral thesis, KTH, Chemistry, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3033.
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NMR methods have been designed and employed in studying ofcomplex liquids and solids formed by surfactants. PGSE NMRexperiments are easily biased by convection; this artifact canbe avoided by changing the sample holder and by usingconvection-compensated pulse sequences. The temperaturedistribution within samples was controlled using thetemperature dependent order parameter for CBr2H2dissolved in a thermotropic nematic solvent.Electronic ringing that often spoils accurate NMR experimentsfor broad lines was removed by the using composite pulses andquadrupole echo sequences with appropriate phase cycles.
Field-dependent81Br and35Cl NMR relaxation studies in micellar solutions ofC16TAX surfactants showed that the structure ordynamics of the hydration shell is more influenced by thesurfactant cation for bromide than for chloride, in agreementwith their position in the Hoffmeister series. The presence ofa small but significant frequency-dependent relaxation showedthat the lateral self diffusion of the anions may be reduced ascompared to its bulk value in diluted solutions but only with afactor of 1.0 - 2.5. The ions are clearly not "bound" to thesurface. A field-dependent2H NMR relaxation study on the CTABr-α-d2and benzene-d6showed an initial one-dimensional micellargrowth followed by the appearance of microemulsion droplets onaddition of benzene. The local mobility of the benzene wasreduced when solubilized in small amounts, consistent with aninitial average location of benzene at the micellar interface.The surfactant diffusion coefficients fromconvection-compensated PGSE NMR experiments in the C12E8-D2O system showed monotonous growth of the micellesupon increasing temperature. Emulsion droplets in the C12E5-decane-D2O system where shown to coarsen according to theOstwald ripening theory after being brought out of equilibriumby a temperature drop. X-ray scattering and2H NMR line-shape and relaxation experimentssuggested that complex solids formed by a partly-sulfatedpolysaccharide and CnTAB exhibit regular ordering at both microscopicand mesoscopic length scales.
Keywords: CTAB, CTAC, C12E8, C12E5, decane, benzene, CBr2H2, polysaccharide, micelle, microemulsion, emulsion,Ostwald ripening, NMR,81Br,35Cl,2H, field- dependent spin relaxation, PGSE, selfdiffusion, convection, ringing, thermometer, generalized Blochequations, EXORCYCLE, quadrupole echo, SAXS, WAXS, cryo-TEM.
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Lee, SeungYong Albert 1975. "Object modeling applied to CTAS." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80098.
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Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.Includes bibliographical references (leaf 49).
by Seung Yong Albert Lee.
S.B.and M.Eng.
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Velcer, Tomáš. "Hyaluronanové hydrogely na bázi CTAT." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-240558.
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This thesis studies the properties and behaviour of phase-separated hydrogels prepared by interaction of hyaluronan with oppositely charged surfactants. Three representatives of surfactants, namely cetyltrimethylammonium bromide, chloride and p-toluensulfonate (CTAB, CTAC, CTAT), were selected for comparison. Using the method of rheology, the fact that the system of Hya-CTAT forms the most rigid hydrogels has been proved. Higher molecular weight of hyaluronan has also direct influence on the volume and stiffness of the newly formed hydrogels. Preparation methods were compared as well. Mixing the stock solutions of entry components appeard to be the most suitable. Small-angle X-ray scattering was used for determination of shape and size of surfactant's micelles, concluding that it has no effect on the volume of formed gels. The results of this study indicate that given gels are to a certain extent competitive and incorporation of hyaluronan into their structure is desirable with respect to its biological activity. This offers a potential usage of these substances in the field of medical applications.
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Mäkivierikko, Aram. "CTG Carbon Calculator." Thesis, Uppsala University, Department of Information Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-101181.
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A carbon dioxide emission calculator for buildings created by the U.S.-based company CTG Energetics, Inc. and based on a Excel file has been converted to a ASP.NET / SQL Server web application. Carbon dioxide emissions are calculated using data given by the user (i.e. floor area, workdays per year) in combination with statistical data used in user-selectable presets (i.e. building type, climate zone, type of water-using fixtures). In most cases a custom value can be inserted instead of using a preset. Emissions attributable both directly and indirectly to the building such as building energy use, domestic water use, landscape/irrigation, transportation, materials used for the building/parking lot and the disposal of solid waste are calculated. The emissions can be compared with a national average and/or emissions from alternate scenarios created for the same building. The web application contains some upgrades and extra functionality that would not have been possible in Excel such as user handling.
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Macias-Balleza, Emma Rebeca. "Comportamiento reologico del sistema CTAT/AGUA/SAL." Université Joseph Fourier (Grenoble), 2002. http://www.theses.fr/2002GRE10018.
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Les solutions de surfactants s'agrégent pour former des microstructures qui dépendent de la concentration et de la température. On étudie un surfactant cationique, le Tosyl-Céthyltrimethylammonium (CTAT) en solution dans l'eau pour des concentrations inférieures à 11%. Dans une première partie, on étudie des concentrations faibles (0Surfactant solutions are known to aggregate and to form microstructures depending upon concentration and temperature. Herein we study water/Cethyltrimethylammonium- Tosilate (CTAT) systems for concentrations under 11%w. CT AT is a cationic surfactant. In a first part we study low concentration systems (O
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Jahanmir, Farid. "Failure detection and repair of threads in CTAS." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/33134.
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Thesis (M. Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.Includes bibliographical references (p. 73).
Reliable, error-free software is hard to come by, and this is especially true for newer, larger, or more complex programs. CTAS, an air traffic control tool, falls into this category, making it a good candidate for research on error compensation. Specifically, this thesis addresses the issue of thread crashes in one portion of CTAS. We reimplement the thread structure in question around a simpler problem, and develop a failure detector and an accompanying repair mechanism to monitor it. These add-on components provide the application with thread consistency by swiftly and transparently recovering from crashes, thereby yielding a more stable, self-sufficient, and generally more reliable operating environment.
by Farid Jahanmir.
M.Eng.and S.B.
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Santos, Zilvam Melo dos. "Estudos das intera??es de quitosana/CTAB/C12E8." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17775.
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Surfactant-polymer interactions are widely used when required rheological properties for specific applications, such as the production of fluids for oil exploration. Studies of the interactions of chitosan with cationic surfactants has attracted attention by being able to cause changes in rheological parameters of the systems making room for new applications. The commercial chitosan represents an interesting alternative to these systems, since it is obtained from partial deacetylation of chitin: the residues sites acetylated can then be used for the polymer-surfactant interactions. Alkyl ethoxylated surfactants can be used in this system, since these non-ionic surfactants can interact with hydrophobic sites of chitosan, modifying the rheology of solutions or emulsions resultants, which depends on the relaxation phenomenon occurring in these systems. In this work, first, inverse emulsions were prepared from chitosan solution as the dispersed phase and cyclohexane as the continuous phase were, using CTAB as a surfactant. The rheological analysis of these emulsions showed pronounced pseudoplastic behavior. This behavior was attributed to interaction of "loops" of chitosan chains. Creep tests were also performed and gave further support to these discussions. Subsequently, in order to obtain more information about the interaction of chitosan with non-ionic surfactants, solutions of chitosan were mixed with C12E8 and and carried out rheological analysis and dynamic light scattering. The systems showed marked pseudoplastic behavior, which became less evident when the concentration of surfactant was increased. Arrhenius and KWW equations were used to obtain parameters of the apparent activation energy and relaxation rate distribution, respectively, to which were connected to the content of surfactant and temperature used in this work
As intera??es tensoativo-pol?mero s?o amplamente usadas quando s?o necess?rias propriedades reol?gicas para aplica??es espec?ficas, como a produ??o de fluidos para explora??o do petr?leo. Estudos das intera??es de quitosana com tensoativos cati?nicos tem chamado aten??o por serem capazes de causar mudan?as nos par?metros reol?gicos dos sistemas abrindo espa?o para novas aplica??es. A quitosana comercial representa uma alternativa interessante para estes sistemas, uma vez que ela ? obtida a partir da desacetila??o parcial da quitina: os s?tos acetilados residuais podem, ent?o, ser usados para as intera??es pol?mero-tensoativo. Tensoativos alquil etoxilados podem ser utilizados neste sistema, pois estes tensoativos n?o i?nicos podem interagir com s?tios hidrof?bicos da quitosana, modificando a reologia de solu??es ou emuls?es resultantes, os quais dependem do fen?meno de relaxa??o ocorrendo nestes sistemas. Neste trabalho, primeiramente, foram preparadas emuls?es inversas de solu??o de quitosana como fase dispersa e cicloexano como fase cont?nua usando CTAB como tensoativo. A an?lise reol?gica destas emuls?es mostrou pronunciado comportamento pseudopl?stico. Esta pseudoplasticidade foi atribu?da ? intera??o por la?os loops de cadeias de quitosana. Ensaios de flu?ncia tamb?m foram executados e deram maior suporte a estas discuss?es. Em seguida, a fim de se obter maiores informa??es sobre as intera??es da quitosana com tensoativos n?o i?nicos, solu??es de quitosana foram misturadas com C12E8 e levadas ?s an?lises reol?gica e de espalhamento din?mico de luz. Os sistemas tiveram elevado comportamento pseudopl?stico, o qual se tornava menos evidente, quando o teor de tensoativo foi aumentado. Equa??es de Arrhenius e de KWW foram usadas para obter par?metros de energia de ativa??o aparente e de distribui??o da taxa de relaxa??o, respectivamente, aos quais foram relacionados em fun??o do teor de tensoativo e da temperatura, usados neste trabalho
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Arumuganainar, Ponnappan. "Automatic soft plaque detection from CTA." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26690.
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Thesis (M. S.)--Biomedical Engineering, Georgia Institute of Technology, 2009.Committee Chair: Tannenbaum, Allen; Committee Member: Skrinjar, Oskar; Committee Member: Yezzi, Anthony. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Keulemans, Laurine Oort Lieneke van Zijgers Gerrie. "CTA carotiden, een alternatief? onderzoek naar de diagnostische waarde van CTA carotiden ten opzichte van MRA carotiden /." Groningen : Groningen : HG, Medisch Beeldvormende en Radiotherapeutische Technieken ; Hanzehogeschool Groningen [Host], 2007. http://scripties.hanze.nl/2007/SAGZ/MBRT/15.pdf.
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Freitas, Lucas Freitas de. "Ablação tumoral fototérmica in vivo utilizando nanobarras de ouro." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-15052012-105851/.
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Ultimamente têm-se buscado tratamentos menos invasivos para o câncer, como os que utilizam campos magnéticos ou luz, e dentre esses últimos, aqueles que fazem uso de materiais, geralmente metálicos, com propriedade de ressonância plasmônica de superfície. O tratamento hipertérmico encaixa-se neste perfil e já apresenta resultados promissores com nanoshells de sílica recoberta por ouro e com nanobarras de ouro maciço, apesar de pouco se saber sobre o mecanismo de ação e sobre como as vias de morte celular são ativadas em tal tratamento. A síntese das nanobarras envolve o uso do composto brometo de cetiltrimetilamônio (CTAB), o qual permanece aderido à superfície das mesmas, porém é caracterizado por apresentar extrema citotoxicidade, fato que incita a modificação do recobrimento das nanopartículas por um biopolímero mais compatível. Estudos recentes indicam que o CTAB aderido à membrana não apresenta citotoxicidade considerável, porém há poucos dados que confirmem tal hipótese na literatura. Este trabalho se propôs a investigar a via de ativação da morte celular, bem como confirmar a hipótese de que as partículas recobertas por CTAB podem ser utilizadas para tratamento antitumoral fototérmico in vivo de forma segura. Para isso, nanobarras de ouro foram sintetizadas pelo método de seeding, sendo parte delas centrifugadas e lavadas com água deionizada por três vezes para retirar o CTAB e a outra parte deixada com CTAB no meio. As partículas foram testadas in vitro pelo teste de citotoxicidade pelo [brometo de 3-(4, 5-dimetiltiazol-2-yl)-2,5-difeniltetrazólio] (MTT) nas linhagens celulares HTC, HepG2, HT-29 e 786-O, e também foram testadas quanto à sua viabilidade com o tempo decorrido desde sua síntese. Após confirmar que as nanobarras centrifugadas e lavadas podem ser utilizadas no tratamento hipertérmico sem riscos à saúde e após verificar que as seeds e as nanobarras devem ser utilizadas até 48 horas depois de sua síntese, as nanopartículas foram utilizadas para tratamento de tumor de Ehrlich (induzido no dorso de camundongos). Para isso, foram organizados quatro grupos experimentais: L (camundongos não receberam nanopartículas, irradiados com laser em 808 nm), N (camundongos receberam nanopartículas, não irradiados com laser), H (camundongos receberam nanopartículas e irradiados com laser em 808 nm) e Controles (camundongos não receberam nanopartículas nem irradiação por laser). O material tumoral foi coletado após a irradiação e submetido à análise histológica, ao teste de quimiluminescência para avaliar a lipoperoxidação de membrana e ao teste de TRAP (do inglês, Total Radical-Trapping Antioxidant Parameter) para avaliar a capacidade antioxidante total. Após a irradiação com 2 W/\'CM POT.2\' ou 720 mW/\'CM POT.2\' de intensidade, houve evidente redução do volume tumoral nos animais do grupo H tratados com laser na maior potência utilizada, com um aumento de 47ºC (temperatura final de 79ºC) observado localmente. Nos animais do grupo H tratados com laser na menor potência utilizada, os danos foram menores. Os animais dos grupos L e H apresentaram semelhante lipoperoxidação, maior que no grupo N (estatisticamente significante somente nos animais tratados com laser em intensidade de 2 W/\'CM POT.2\'), e a capacidade antioxidante dos tumores dos animais do grupo H foi elevada no protocolo com laser em 2 W/\'CM POT.2\'. Os resultados indicam que a necrose é a via de morte ativada prioritariamente neste caso e que o tratamento com as nanobarras se mostrou eficaz.Less invasive cancer treatments, likewise those based on magnetic fields or light, are in the most common aims of researchers nowadays. Regarding light based treatments, those in which metallic, plasmonic materials are highlighted in research field. Hiperthermic treatment fits this profile, once it already presents promising results with gold-coated silica nanoshells and with gold nanorods, although little is known about its action mechanism or about how cell death pathways are activated. The compound cetyltrimethylammonium bromide (CTAB) is necessary for the nanorods synthesis, but is known to be extremely cytotoxic, fact that instigates the modification of nanorods surface coating by a compatible biopolymer. Recent studies indicate that surface-adhered CTAB does not present significant cytotoxicity, but there are few evidences to confirm this hypothesis in the literature. This study aims to investigate the cell death pathway that can be activated, as well as to confirm the possibility of safe CTAB-coated nanoparticles use in antitumor in vivo treatments. For that, gold nanorods were synthesized by the seeding method and part of them were centrifuged and washed with deionized water to eliminate CTAB of the solution and the rest remained with CTAB. The particles were tested in vitro by [3-(4, 5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) cytotoxicity test, in HTC, HepG2, HT-29 and 786-O cancer cell lines, and investigated regarding their viability through time after their synthesis. After confirming that centrifuged and washed nanorods can be used in hiperthermic therapy without health risks, and after find out that seeds and nanorods must be used within 48 hours after their synthesis, those nanoparticles were used for in vivo hyperthermic Ehrlich tumor (induced on the back of mices) treatment. Four experimental groups were organized: L (mice did not receive nanoparticles, treated with laser at 808 nm), N (mice received nanoparticles, not treated with laser), and H (mice received nanoparticles and treated with laser at 808 nm) and Controls (mice did not receive nanoparticles and were not treated with laser). A tumor biopsy was taken after laser irradiation and was subjected to histological analysis, by a chemiluminescence assay to evaluate membrane lipoperoxidation, and by Total Radical-Trapping Antioxidant Parameter (TRAP) assay as well, to evaluate total antioxidant capacity. After irradiation with laser (intensities of 2 W/\'CM POT.2\' or 720 mW/\'CM POT.2\'), there was an evident tumor volume reduction in animals of H group treated with higher power laser, with a 47ºC rise in temperature (final temperature was 79ºC) observed locally. The damages in the tumors irradiated with lower power laser were less intense. The animals of L and H groups showed similar membrane lipoperoxidation, which was more intense than in N animals (statistically significant just in the animals treated with higher intensity of radiation). The antioxidant capacity of H animals tumor was elevated also in the animals treated with higher energy. Our results indicate that necrosis is the main activated cell death pathway in this case, and that nanorods treatment is worth it.
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Viana, Rommel Bezerra. "Espectroscopia de infravermelho de cristalitos de surfactantes." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-23062008-094327/.
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O objetivo deste trabalho é estudar o nível de organização dos cristalitos de surfactantes aniônico, catiônico e zwiteriônico com o aumento na densidade destas moléculas sobre um cristal de germânio. As análises foram realizadas por espectroscopia de infravermelho com transformada de Fourier acoplada à técnica de reflexão total atenuada (FTIR-ATR). Este estudo apresenta importantes aspectos na organização do dodecilsulfato de sódio (SDS), do N-hexadecil-N,N-dimetil-3-amônio-1-propanosulfato (HPS), do brometo de hexadeciltrimetilamônio (CTAB) e do brometo de dodeciltrimetilamônio (DTAB). No SDS é observado um deslocamento de 1.7 cm-1 para valores de maior frequência na banda de estiramento assimétrico do CH2, vass (CH2), enquanto que é observado um deslocamento de 0.9 cm-1 na banda de estiramento simétrico, vsim (CH2). Este deslocamento para valores de maior frequência nas bandas de estiramento está associado com um aumento na desorganização da cadeia alifática com o aumento na densidade de moléculas sobre o elemento de ATR. A banda de deformação angular do CH2, δ(CH2), apresenta um valor em 1468 cm-1 que é também um indicativo de desorganização. No CTAB não é observado variações acentuadas nos valores das frequências vibracionais. Na banda vass (CH2) do DTAB é observado um deslocamento de 4.5 cm-1 para valores de menor frequência. Embora seja observado valores próximos de 2920 cm-1 para a banda vass (CH2), que é um indicativo do estado líquido de surfactantes, o que é observado nesse estudo são cristalitos de DTAB. O deslocamento da banda vsim (CH2) do DTAB é da ordem de 2 cm-1. Estas mudanças nas bandas vass (CH2) e vsim (CH2) são um indicativo da diminuição nas conformações gauche e um aumento nas conformações trans ao longo da cadeia alifática. O valor da freqüência em torno de 1472 cm-1 para a banda δ(CH2) é também um indicativo de uma maior organização na cadeia de CH2 do DTAB. Para o HPS é observado um deslocamento de 2.6 e 2.7 cm-1 para valores de maior frequência nas bandas vass (CH2) e vsim (CH2), respectivamente. A banda δ(CH2) do HPS apresenta um deslocamento de 4 cm-1 para valores de maior frequência. A variação nas bandas vass (CH2), vsim (CH2), e δ(CH2) ressalta o aumento na desorganização da cadeia alifática com o aumento na densidade de moléculas de HPS sobre o germânio.The objective of this work is study the order level of anionic, cationic and zwitterionic surfactants with the increase of their density packing on the surface of a germanium element. The analyses were performed by a Fourier transform infrared-attenuated total reflection spectroscopy. This study shows important insights on the conformational order of sodium dodecyl sulfate (SDS), N-hexadecyl-N-N -dimethyl-3-ammonio-1-propane-sulfonate (HPS), hexadecyl-trimethylammonium bromide (CTAB) and dodecyl trimethylammonium bromide (DTAB). It is observed a shift of 1.7 and 0.9 cm-1 to higher frequency values of the CH2 asymmetric (vass (CH2)) and symmetric (vsim(CH2)) stretching bands for the SDS molecules, respectively. The latter shift to higher frequency values is associated with the disorder of the aliphatic chain due to the increase of density packing of SDS molecules on the germanium element. The CH2 scissoring band [δ (CH2)] shows a value in 1468 cm-1, which is also an indicative of conformational disorder. It is not observed any accentuated change on the vibrational frequency values of the CTAB molecules. The vass (CH2) band of the DTAB molecules is shifted 4.5 cm-1 to lower frequency values. Although it is observed values near 2920 cm-1 for the vass(CH2) band, indicating a surfactant liquid phase, it is shown in this study that there are indeed DTAB crystallites. The shift of DTAB vsim(CH2) band is around 2 cm-1. These changes in vass(CH2) and vsim(CH2) band are an indicative of a decrease in gauche conformations and an increase in all-trans conformations over the aliphatic chain. The frequency value around 1472 cm-1 for the δ(CH2) band is also an indicative of the order in CH2 chain of DTAB. It is observed a shift of 2.6 and 2.7 cm-1 to higher frequency values of vass (CH2) and vsim(CH2) bands of the HPS molecule, respectively. The δ(CH2) band of the HPS molecule presents a shift of 4 cm-1 to higher frequency values. These variations in vass (CH2), vsim(CH2), and δ(CH2) bands stand out the disorder of the aliphatic chain due to the increase of the density packing for the HPS molecules on the germanium surface.
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Mills, Amanda Jayne. "Investigating cetyltrimethylammonium bromide (CTAB) reverse microemulsions using nuclear magnetic resonance." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6528/.
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This thesis investigates CTAB/alcohol/hexane/water reverse micelles, where the alcohol is butanol, pentanol, hexanol and heptanol, through the use of nuclear magnetic resonance (NMR). Diffusion and relaxation measurements showed the alcohol is distributed between the reverse micelle (RM) interface and the continuous phase, and exchanges between these two environments. The exchange of pentanol in the CTAB/pentanol/hexane/water RM was investigated using 20 relaxation exchange spectroscopy (REXSY), and was determined to be on the order of milliseconds. The proportion of alcohol in the interface was determined for all microemulsions which decreases as a function of increasing alcohol size. Each microemulsion was investigated by molecular simulations which produced oblate shaped droplets, which was associated with a non-homogeneous distribution of alcohol in the interface. CTAB was determined to be present in solely the interface of the microemulsions with the exception of the CTAB/pentanol/hexane/water RM. The CTAB/pentanol/hexane/water RM behaves differently as initially the CTAB was distributed between the RM and the continuous phase however, after time, the surfactant is re-distributed so that CTAB is present in only the interface. The RM sizes were determined using the CTAB diffusion coefficients. The droplet sizes decreased as a function of alcohol chain length, with the exception of the CTAB/pentanol/hexane/water RM which, after time, gave the largest droplet of all the microemulsions.
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Fernandes, Selma Kovalski. "Construção no núcleo de educação a distância do SENAI/CTAI." Florianópolis, SC, 2005. http://repositorio.ufsc.br/handle/123456789/102881.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção.Made available in DSpace on 2013-07-16T02:11:03Z (GMT). No. of bitstreams: 0
Este trabalho tem como objetivo apresentar e descrever o processo de construção de um Núcleo de Educação a Distância, dentro do SENAI de Santa Catarina, no Centro de Tecnologia em Automação e Informática - CTAI, apresentando um relato das experiências e trabalhos desenvolvidos desde as primeiras iniciativas em educação a distância, até a estrutura atual, bem como as competências adquiridas pelo núcleo no desenvolvimento e aplicação de projetos e programas realizados a distância, enfatizando a criação de um ambiente virtual próprio, denominado DIDATIX e que posteriormente deu origem ao Portal do Conhecimento em EAD, que é o local que agrega todos os cursos e atividades a distância desenvolvidas, bem como as intenções de continuidade.
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Palacio, Navarro Joaquim. "Indirect dark matter searches: MAGIC & CTA." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/462764.
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Després de dècades d'observacions, és evident que les partíicules del model estàndard són insuficients per explicar el fort desequilibri gravitacional observat a diverses regions astronòmiques,
de diferents escales cosmològiques, des de satèl·lits de la Via Làctia fins a cúmuls de galàxies.
Si bé és veritat que algunes teories suggereixen a una modificació de les lleis gravitacionals actuals, l'existència d'una partícula (o un grup de partícules) nova, interaccionant de forma feble amb les partícules del model estàndard està considerada com l'opció més viable. Estimacions recents prediuen que aquest tipus de matèria fosca és 4 vegades més present que la matèria del model estàndard, modelant així la formació de les grans estructures de l'univers al llarg de la vida d'aquest.
Un escenari general de la matèria fosca és el dels WIMPs, partícules genèriques massives, amb masses entre pocs GeVs i alguns TeV, interaccions de l'ordre de les interaccions dèbils del model estàndard, i o bé estables o amb temps de vida mitjana prou llargs. L'escenari WIMP ha estat llargament debatut, i té l'avantatja d'estar a l'abast dels instruments més potents construïts a la terra, proporcionant així possibles deteccions independents que podria validar el descobriment.
En particular em centro en cerques indirectes de matèria fosca, on s'espera que WIMPs anihilats o decaient emetin rajos gamma amb energies detectables per telescopis IACT, com per exemple els telescopis MAGIC, actualment operant des de La Palma o la futura xarxa de telescopis CTA.
El senyal esperat de rajos gamma d'aquesta matèria fosca pot ser moderadament extensa, comparada amb el camp de visió dels IACTs, cosa que afegeix certa complexitat a les cerques de matèria fosca realitzades per a aquests telescopis.
En aquesta tesi, he contribuït a l'esforç realitzat per MAGIC en cerques indirectes de matèria fosca a diferents nivells d'analisis. He desenvolupat una eina per gestionar volums massius de dades que són típicament generats per MAGIC, però també per tota la comunitat experimental de física d'altes energies. També he desenvolupat un MonteCarlo per a fonts extenses que s'ajusta a l'emissió esperada de la font, obtenint així les funcions correctes de resposta de l'instrument. Finalment, un mètode per a optimitzar la configuració d'apuntat durant les observacions de fonts moderadament extenses amb IACTs ha estat proposat. El mètode té en compte la resposta finita dels IACTs al llarg de tot el camp de visió per a proporcionar la distància òptima a la qual el telescopi ha d'apuntar a la font, així com, quina seria la regió d'integració més adient. Apliquem aquest mètode per primera vegada a cerques de matèria fosca en galàxies satèl·lits de la Via Làctia. També exposo la meva contribució al telescopi més gran que operarà a CTA, el LST, que dominarà la sensibilitat de cerques de WIMPs estàndard.
Límits a la secció eficaç i/o temps de vida mitjana són imposats mitjançant 60 hores d'observació de la galàxia Triangulum-II i 202 hores del cúmul de galàxies de Perseus. En ambdues cerques, fem ús del mètode de màxima versemblança, optimitzat per a la morfologia espacial i energètica del senyal esperat de rajos gamma. Obtenim sensibilitats a la secció eficaç de 3·10^{-26}~\cm^{3}\s^{-1} i
temps de vida mitjana de 0.3·10^{25}~\s, essent aquests els resultats més restrictius obtinguts amb MAGIC en cerques de WIMPs.Decades of observational evidences have been accumulated to show that Standard Model (SM) particles cannot totally explain the strong gravitational unbalance observed in several astronomical regions, at all cosmological scales, from that of Milky Way (MW) satellite galaxies, to that of Cluster of Galaxies (CGs). Although some theories argue for the modification of the gravitational laws, the existence of a new massive particle (or a set of them), interacting only weakly with SM particles, provides a preferred explanation. It is estimated that this form of Dark Matter (DM) roughly accounts for 4 times the amount of SM matter, therefore shaping the evolution of cosmic structures along the history of the Universe. A well-motivated general framework for DM is that of a Weakly Interacting Massive Particle (WIMP), generic massive particles with a mass range expected between few GeVs and few hundreds TeV, interaction strengths at the weak scale, and either stable or very long lived. The WIMP paradigm has been long debated, and has the advantage of being at reach by different of the top-class instruments of the current times, so that a putative discovery could be validated independently. We focus on the indirect search of DM, where annihilating or decaying WIMPs are expected to emit gamma rays at energies detectable by Imaginc Atmospheric Cherenkov Telescopes (IACTs), as the currently operating MAGIC telescopes or the future Cherenkov Telescope Array (CTA). The expected DM signal can be moderate extended when compared to IACTs Field of View (FoV), what challenges the performance of the \acrshort{dm} search of these instruments. In this thesis, I contribute to the MAGIC ongoing efforts on indirect DM searches at different analysis levels. A tool for handling the massive data products generated by current high energy experiments is developed. More over, a tailored Monte Carlo (MC) for moderate extended sources is proposed as an upgrade of the current general MC for extended sources. Finally, a method to optimize the pointing strategy of IACTs while observing moderate extended sources taking into account the off-axis performance of the instrument has also been developed and, implemented for the first time to indirect DM searches on highly DM dominated nearby dwarf Sphereoidal galaxies (dSphs). I also show my contribution to the largest telescope to be part of CTA, the Large Size Telescopes, that will dominate the CTA sensitivity for standard WIMP searches. Constraints on the WIMP thermally averaged cross-section and/or decay life-time are put with 60~hours of data in the recently discovered dSph Triangulum-II and 202~hours on the Perseus CG. On both searches, we apply a binned likelihood analysis optimized for the spectral and morphological features of gamma-ray signals of DM from annihilating or decaying WIMPs. We reach sensitivities to the thermally averaged cross-section of 3·10^{-26}~\cm^{3}\s^{-1} and decay life-times of 0.3·\times10^{25}~\s, being this the most constraining MAGIC results on WIMP searches.
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Schmidt, Kristina H. "CTG trinucleotide repeat instability in Escherichia coli." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/14353.
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In order to identify cellular factors that affect trinucleotide repeat stability, changes in the length of a (CTG)43 repeat were studied over 140 generations in wild-type Escherichia coli and in strains that are deficient in post-replicative mismatch repair, secondary structure repair and homologous recombination. It is shown that (CTG)43 inserted into pUC18 expands and contracts in wild-type E. coli in an orientation-dependent manner that is unaffected by transcription. In cells deficient in post-replicative mismatch repair (CTG)43 repeat instability is greater than in wild-type cells but orientation-independent. The observation of single trinucleotide insertions and deletions in these mutator mutants indicates that replication slippages of 3 bp occur in vivo leading to repeat expansion and contraction if left unrepaired. Compared to wild-type cells large deletions are reduced in these mutator mutants, but only if the CTG sequence serves as the lagging strand. Based on the opposing effects of mismatch repair a model is proposed in which orientation-dependent CTG repeat instability in mismatch repair proficient cells is caused by the repair of 3-bp slippages. This leads to the creation of larger deletions during repair synthesis due to the formation of unusual secondary structures by the CTG sequence on the lagging strand. Mutations in the recA and sbcCD genes do not affect the stability of plasmid-borne CTG repeats. Similarly the viability of recA-deficient strains carrying chromosomal insertions of (CTG)25 and (CTG)43 suggests that, unlike long palindromes, these trinucleotide repeats are not substrates for the structure-directed nuclease complex SbcCD or, alternatively, they do not form secondary structures frequently enough to cause lethality in recA-deficient hosts. In contrast, a mutation in the recG gene, also involved in homologous recombination, severely destabilises the (CTG)43 repeat in a strongly orientation-dependent manner that exceeds all other tested mutants. Possible explanations for this observation are discussed.
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Sandberg, Henrik, and Rasmus Öhman. "Position sizing methods for a trend following CTA." Thesis, KTH, Industriell ekonomi och organisation (Inst.), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-147387.
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This study examines whether a trend following managed futures fund can improve its performance by changing its position sizing method. Trades for a simple trend following strategy was simulated on 47 futures contracts over the period 1990-2012, using varying methods for determining position size. Eleven different position sizing methods where investigated, among them Target Volatility, Omega Optimization and correlation ranking methods. Both methods previously detailed in academic papers as well as novel approaches was implemented, and compared to the baseline performance of the strategy. The results from this study show that the Target Volatility method, and to some degree Max Drawdown Minimize and Dynamic Stop Lock-In, improved the performance of strategy. The final recommendation for a trend following managed futures fund is to use Target Volatility as position sizing method, possibly in conjunction with Max Drawdown Minimize.Denna studie undersöker huruvida en trendföljande managed futures-fond kan förbättra sina resultat genom att ändra positionsskalningsmetod. Handel med en enkel trendföljande strategi simulerades på 47 futureskontrakt åren 1990-2012, för olika metoder att för bestämma positionsstorlek. Elva positionsskalningmetoder undersöktes, exemplevis Target Volatility, Omega Optimization och metoder baserade i korrelationsrankning. Både tidigare beskrivna metoder och nya tillvägagångssätt testades, och jämfördes med den grundläggande strategin med avseende på risk och avkastning. Denna studies resultat visar att framförallt Target Volatility, och i viss uträckning Max Drawdown Minimize och Dynamic Stop Lock-In förbättrade nyckeltalen för den handlade strategin. Den slutgiltiga rekommendationen för en trendföljande managed futures-fond är att använda Target Volatility som positionsskalningsmetod, möjligtvis tillsammans med Max Drawdown Minimize.
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Erlandsson, Diana, and Linda Håkansson. "Barnmorskors och läkares dokumentation av CTG : Ett kvalitetsarbete på förlossningen i Karlskrona." Thesis, Linnéuniversitetet, Institutionen för hälso- och vårdvetenskap (HV), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26204.
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Bakgrund: SFOG har tillsammans med SBF, SNS och LÖF upprättat riktlinjer för förlossningsvården som bland annat berör dokumentation av CTG. Dessa har tagits fram genom ”Projekt säker förlossningsvård” och antagits av Blekingesjukhuset Karlskrona år 2008. Syfte: Syftet var att undersöka barnmorskors och läkares följsamhet av CTG-dokumentation, vid aktivt förlossningsförlopp, i förhållande till lokala PM, aktuella riktlinjer och nationella styrdokument på förlossningsavdelningen, Karlskrona. Metod: Retrospektiv journalgranskningmed deskriptiv design har använts. Datainsamling omfattar tidsperioden 2011-07-01 t.o.m. 2012-03-04. Totalt ingick 748 journaler och 1547 dokumentationer i studien. Dataanalys har skett med hjälp av statistikprogrammet SPSS. Resultat: Av journalerna hade 22% ingen dokumentation om CTG och 46% av dokumentationerna innehöll en klassifikation. Åtgärd har dokumenterats i 80% och dokumentationerna var skriven utan förkortning i 45%. Följsamheten av klassificering och åtgärd tillsammans var totalt 44%medan barnmorskors var 38% och läkares 8%. Konklusion: Följsamheten av CTG-dokumentationbehöver förbättras på förlossningsavdelningen i Karlskrona. Majoriteten av vad som dokumenteras följer inte PM, riktlinjer och nationella styrdokument.Background: SFOG, SBF, SNS and LÖF have conducted guidelines for obstetric care including documentation of CTG. These have been developed during “Projekt säker förlossningsvård” and adopted 2008 by the hospital in Blekinge, Karlskrona. Aim: The aim of this study was to examine the compliance of CTG documentation by midwives and physician, during active labor, in relation to local PM, current guidelines and national policy at the labor ward Karlskrona. Method: Retrospective study using descriptive design was used. Data collection covers the time period 2011-07-01 to 2012-03-04. Totally 748 records and 1547 documentations were reviewed. Data analysis was progressed in SPSS. Result: Of the total records, 22% did not have any documentation about CTG and 46% of the collected documentations had a classification. Action was documented in 80%, and the documentations were written without an abbreviation in 45%. Compliance of classification and action together was 44%, midwives had 38% and physicians 8%. Conclusion: The compliance of CTG documentation needs improvement in the labor ward in Karlskrona. The majority of documents are not followed by PM, guidelines and national policy documents.
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Letaïef, Ounalli Nouha. "Investigation après immersion dans un liquide physiologique synthétique, de l'interface de verres bioactifs à porosité contrôlée : influence des paramètres de synthèse sur les propriétés physico-chimiques et biologiques." Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S136/document.
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Dans ce travail, nous avons élaboré, par voie sol-gel, un nouveau verre bioactif mésoporeux : 92S6 (92% SiO2, 6% CaO, et 2% P2O5). Cette synthèse a été développée en variant les paramètres telles que la température, la nature du tensioactif (ionique (le CTAB) ou non ionique (le P123)) et la longueur de la chaîne carbonée pour chaque type de tensioactif et en étudiant leurs effets sur les propriétés texturales du verre. Des études physico-chimiques et biologiques in vitro ont été menées sur ces biomatériaux. Par la suite, nous avons réalisé une étude structurale de l'eau confinée dans les pores du verre synthétisé qui a révélé une modification de l'ordre locale en comparaison avec l'état massique (bulk). Ceci permet un contrôle de la quantité de principe actif à incorporer dans les pores, du taux d'adsorption et de la cinétique de libération. La diffraction des Rayons X aux petits angles, l'analyse texturale par BET et les images de la microscopie électronique en transmission ont mis en évidence l'influence des paramètres de synthèse sur les propriétés texturales des verres synthétisés. En effet, l'échantillon synthétisé avec le tensioactif ionique (CTAB) présente une structure mésoporeuse non ordonné, alors que l'utilisation du tensioactif non-ionique (P123) favorise l'obtention d'un verre mésoporeux ayant une structure poreuse ordonnée. Dans le cas des verres synthétisés avec les différentes longueurs de la chaîne carbonée des tensioactifs, nous avons démontré que la longueur de la chaîne alkyle du tensioactif ionique détermine la morphologie des particules et les caractéristiques texturales des 3 verres, alors que nous avons noté une absence de différences significatives dans la texture des matériaux dans le cas des 3 verres synthétisés avec les tensioactifs non ioniques. Nous avons aussi mis en évidence l'influence de la température de synthèse sur les propriétés texturales des verres synthétisés. Nous avons démontré que la température de synthèse agit sur le diamètre des pores de manière différente selon la nature du tensioactif. L'augmentation de la température de synthèse conduit à une augmentation de la dimension des cavités dans le cas des verres synthétisés avec le P123, alors que dans le cas des verres synthétisés avec le tensioactif ionique CTAB, l'augmentation de la température de synthèse conduit à une diminution des diamètres des pores. Nous avons démontré que la morphologie des particules et les caractéristiques texturales des verres influent sur la bioactivité de ces derniers. Nous avons obtenu des verres bioactifs comme en témoigne la formation de la couche d'hydroxyapatite à leurs surfaces une fois immergés dans le SBF, ce qui explique l'intérêt des ces verres dans le domaine de la chirurgie orthopédiqueIn this study, a new mesoporous bioactive glass 92S6 (92% SiO2, 6% CaO, and 2% P2O5), was prepared by sol-gel method. The purpose of this study was first to investigate the effect of synthesis parameters such as aging temperature, surfactant type and surfactant carbon chain length on the glass textural properties and then to investigate these effect on the glass bioactivity. Then, we conducted a structural study of water confined in the pores of the synthesized glass. This study revealed a change of the local order of confined water in comparison with the bulk. This allows control of drugs to be incorporated into the pores, the adsorption rate and the release kinetics. The small-angle XRD patterns (SAXRD), the Brunauer–Emmett–Teller (BET) method and the Transmission Electron Microscopy (TEM) studies evidence the influence of the structure-directing agent (ionic surfactant CTAB or non-ionic P123) in the generation of unorganized or well ordered pores in the 92S6 glass. We also demonstrated that when we synthesized glasses with a same composition using the same technique (sol-gel), in presence of surfactants with different carbon chain length, there is a direct correlation between the surfactant and textural properties and structural characteristics. As observed from small-angle XRD patterns and TEM images, synthesis at different temperatures lead to the formation of mesoporous glasses. The properties of these glasses are extremely dependent on the synthesis temperature. We demonstrated also that the bioactivity may be significantly modified by a change on glass textural properties. Finally, the samples were analyzed to quantify the apatite formation ability when soaked in SBF solution. The physico-chemical studies showed apatite-like phases formed at the glasses surface when soaked in SBF. So, our mesoporous glasses are bioactive. These characteristic mesoporous glasses will display good future applications in bone tissue repairing and engineering
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Lindkvist, Kristoffer. "The effects of volatility and correlation on CTA strategies." Thesis, KTH, Industriell ekonomi och organisation (Inst.), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-102593.
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Detta examensarbete analyserar effekterna av volatilitet och korrelation på trading strategier brukade av Commodity Trading Advisors (CTA´s). Denna studie bygger på en kvantitativ analys av data som insamlats från Barclay Hedge database. Studien har genomförts i samarbete med RPM Risk & Portfoliomanagement i Stockholm, Sverige. Traditionellt sett, när globala marknader visar på högre volatilitet än genomsnittet, har detta identifierats som ett tecken på en björnmarknad med negativ avkastning på aktier. Förhållandet mellan volatilitet och negativ avkastning på aktier var initialt uppmärksammat av Black år 1976. Förhållandet mellan volatilitet och korrelation mellan marknaderna har analyserats i denna uppsats och resultaten tyder på att högre nivåer av volatilitet för även med sig högre nivåer av korrelation. Den uppmäta korrelationen mellan volatilitet och korrelation var så hög som 0,7. CTA´s handlar så kallade Managed Futures, framtida kontrakt på råvaror, där varje kontrakt har en lång och kort position vilket gör det möjligt att nå en positiv avkastning även under hög volatilitet. De tre mest använda strategierna för CTA´s, short term trading (kortsiktig handel), fundamental handel och Trendföljande handel, presenteras i denna studie och deras möjlighet att bära positiv avkastning i en mycket volatil marknad härleds. Resultaten tyder på att en hög volatilitetsregim med hög korrelation gynnar den kortsiktiga handelsstrategin mer än fundamental och trendföljande handel.This master thesis analyses the impacts of volatility and correlation on common strategies for Commodity Trading Advisors (CTAs). It is based on a quantitative analysis of data gathered from the Barclay Hedge database. The study was done in cooperation with RPM Risk and Portfolio Management based in Stockholm, Sweden. Traditionally, when global markets see higher levels of volatility this has been identified as a sign of a bear market with negative returns on equities. The relationship between volatility and negative returns on equities was first acknowledged by Black in 1976. The relationship between volatility and correlation between markets has been analyzed in this thesis and the findings suggest that higher levels of volatility brings with it higher levels of correlation. The correlation between volatility and correlation is as high as 0.7. CTAs trade future contracts where every contract has a long and short position which is making it possible to reach positive returns even under extreme volatility. The three most popular strategies for CTAs, Short Term trading, Fundamental trading and Trend Following, are presented in this study and their possibility to have positive returns in highly volatile environments is derived from the analysis. The findings suggest that in a high volatility regime with high correlation Short Term trading strategy has been the most profitable.
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Chan, Nelson Lap Shun. "IDENTIFICATION OF ACTIVITIES INVOLVED IN CAG/CTG REPEAT INSTABILITY." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_diss/832.
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CAG/CTG repeat instability is associated with at least 14 neurological disorders, including Huntington’s disease and Myotonic dystrophy type 1. In vitro and in vivo studies have showed that CAG/CTG repeats form a stable hairpin that is believed to be the intermediate for repeat expansion and contraction.
Addition of extra DNA is essential for repeat expansion, so DNA synthesis is one of the keys for repeat expansion. In vivo studies reveal that 3’ CTG slippage with subsequent hairpin formation (henceforth called the 3’ CTG slippage hairpin) occurs during DNA synthesis. It is proposed that hairpin tolerance machinery is activated because prolonged stalling of DNA polymerase triggers severe DNA damage. As a means toward studying the hairpin-mediated expansion, we created a special hairpin substrate, mimicking the 3’ CTG slippage hairpin, to determine which polymerase promotes hairpin bypass. Our studies reveal polymerase β (pol β) is involved in the initial hairpin synthesis while polymerase δ (pol δ) is responsible for the resumption of DNA synthesis beyond the hairpin (extension step). Surprisingly, we also found that the pol δ can remove the short CTG hairpin by excision of the hairpin with its 3’ to 5’ exonuclease activity.
Besides repairing the hairpin directly, resolving the hairpin is an alternative pathway to maintain CAG/CTG repeat stability. With limited understanding of which human helicase is responsible for resolving CAG/CTG hairpins, we conducted a screening approach to identify the human helicase involved. Werner Syndrome Protein (WRN) induces the hairpin repair activity when (CTG)35 hairpin is formed on the template strand. Primer extension assay reveals that WRN stimulates pol δ synthesis on (CAG)35/(CTG)35 template and such induction was still found in the presence of accessory factors. Helicase assay confirms that WRN unwinds CTG hairpin structures.
Our studies provide a better understanding of how polymerases and helicases play a role in CAG/CTG repeat instability. Considering CAG/CTG repeat instability associated disorders are still incurable, our studies can provide several potential therapeutic targets for treating and/or preventing CAG/CTG repeat associated disorders.
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Qian, Yuwei. "Effect of cationic surfactant (CTAB) in the electrokinetic remediation of diesel-contaminated soils." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0004/MQ32224.pdf.
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Pereira, Maria N?bia Gomes de Lucena. "Avalia??o da aprendizagem no Curso T?cnico em Agroind?stria, no IFCE- Campus Iguatu, atrav?s do desenvolvimento de atividades em um projeto de pesquisa com umbu-caj?" Universidade Federal Rural do Rio de Janeiro, 2010. https://tede.ufrrj.br/jspui/handle/jspui/2350.
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This work has analyzed the contribution of the development of activities of a research project applied in the teaching-learning process, hoping that the students of the Technical Course in Agroindustry of the Federal Institute of Education, Science and Technology ? Campus Iguatu, in the class of fruits and vegetables processing as active agents, comprehend and solidify their knowledge. In that sense, students of the Technical Course in Agroindustry produced teaching materials that could be used for the capacity of the producers of Vila Cajazeiras, with formulation techniques that could assemble value to the fruit of umbucaj? (Spondias sp). To evaluate the pedagogical process, two groups of 16 students have been created. The first group consisted of students from the Technical Course in Agroindustry with the curriculum in the integrated course (test group) and the second, students from the Technical Course in Agroindustry with the curriculum in the modulated course (control group). These students had already taken the class of fruits and vegetables processing the semester before. The evaluation method used was to evaluate the attitude of the individual, building a questionnaire about the umbu-caj? fruit with affirmatives referent to the necessary concepts and knowledge to comprehend these steps. This instrument has been applied in three different steps. For the control group, the instrument has been applied only once. In the extension activity, 16 people from the community have participated. The students were evaluated by the producers that participated in the extension activity. The processed product, nectar of umbu-caj?, has been evaluated referencing the physical-chemical, sensorial and microbiological parameters. In the physical-chemical determinations, the current legislation has been used to compare the results. In the sensorial evaluations, accepting tests have been used. As for the teaching-learning process, it has been observed that the test scores for each subject have been gradually rising as the learning would materialize, reaching the final test with more homogeneous answers. The medium scores were 4,8; 5,2 and 6,9 for T1, T2 and T3, respectively. As the students were being inserted in the context of the contemplated units of the class, it has been noted that the developed activities contributed to elevate their knowledge. In the control group the learning level was lower than in the test group. The results of the second group (control group) indicate that the students of the first group (test group) obtained higher comprehension of the proposed activities in this project, making this student search for interdisciplinary, produce his own learning, establish non-traditional pedagogical relations and learn new methods to assimilate new information and processing technologies of the umbu-caj? fruit, to better support its proposed work. Therefore, this work was important to link the student to the researching world, making him an active agent of all the process, assigning him with responsibility and making it possible for him to create different ways of constructing his own knowledge.
O presente trabalho analisou a contribui??o do desenvolvimento de atividades de um projeto de pesquisa aplicado no processo de ensino-aprendizagem, esperando-se que os estudantes do Curso T?cnico em Agroind?stria do Instituto Federal de Educa??o, Ci?ncia e Tecnologia - Campus Iguatu, da disciplina de processamento de frutos e hortali?as, como agentes ativos, compreendessem e solidificassem o conhecimento. Nesse sentido, estudantes do Curso T?cnico em agroind?stria produziram o material did?tico que pudesse ser utilizado para a capacita??o dos produtores da Vila Cajazeiras, com t?cnicas de formula??es para que eles pudessem agregar valor ao fruto do umbu-caj? (Spondias sp). Para avaliar o processo pedag?gico, foram constitu?dos dois grupos de 16 estudantes, sendo o primeiro do Curso T?cnico em Agroind?stria da matriz curricular do Curso integrado (Grupo Teste) e o segundo, por alunos do Curso T?cnico em Agroind?stria da matriz curricular do curso modulado (Grupo Controle). Esses alunos j? haviam cursado a disciplina de processamento de frutos e hortali?as no semestre anterior. Utilizou-se o m?todo de avalia??o de atitude do indiv?duo construindo-se question?rio relativo ao fruto do umbu-caj? com afirmativas referentes aos conceitos e conhecimentos necess?rios para compreender estas etapas. Esse instrumento foi aplicado em tr?s etapas diferentes. Para o Grupo controle, o instrumento foi aplicado apenas uma vez. Na atividade de extens?o participaram 16 pessoas da comunidade. Os alunos foram avaliados pelos produtores que participaram da atividade de extens?o. O produto processado, n?ctar de umbu-caj?, foi avaliado em rela??o aos par?metros f?sico-qu?micos, sensoriais e microbiol?gicos. Nas determina??es f?sico-qu?micas, para comparar os resultados, utilizou-se a legisla??o vigente. Nas avalia??es sensoriais, utilizaram-se testes de aceita??o. Quanto ao processo de ensino-aprendizagem, verificou-se que a m?dia para cada sujeito foi aumentando gradativamente nos testes, ? medida que a aprendizagem se concretizava, chegando ao ?ltimo teste com uma maior homogeneidade nas respostas, cujas m?dias foram 4,8; 5,2 e 6,9 para T1, T2 e T3, respectivamente. Na medida em que os alunos foram sendo inseridos no contexto das unidades contempladas na disciplina, verificou-se que as atividades desenvolvidas contribu?ram para elevar seu n?vel de conhecimento. O Grupo Controle o n?vel de aprendizagem foi menor do que no grupo teste. Os resultados obtidos no segundo grupo (grupo controle) indicaram que os estudantes do primeiro grupo (grupo teste) obtiveram melhor compreens?o das atividades propostas neste projeto, proporcionando a esse aluno buscar a interdisciplinaridade, produzir seus pr?prios conhecimentos, estabelecer rela??es pedag?gicas n?o-tradicionais e aprender outro m?todo para assimilar novos conhecimentos e tecnologias de processamento do fruto de umbu-caj?, para melhor fundamentar a sua proposta de trabalho. Portanto, o trabalho foi importante para vincular o estudante ao mundo da pesquisa, fazendo-o um agente ativo de todo o processo, atribuindo-lhe responsabilidade e possibilitando-lhe um modo diferente de construir seu pr?prio conhecimento.
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Aarøe, Øyvind. "En sammenligning av RTA og CTA: : testsituasjonens innvirkning på resultatet." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10320.
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CTA har vært utsatt for sterkt kritikk av eksperter. Dette er kritikk som spesielt fokuserer på metodens validitet og gjennomførelse. Denne masteroppgaven fokuserer på brukbarhetstester med et annet perspektiv; brukernes opplevelse av metoden. Oppgaven prøver finne ut om, og eventuelt i hvor stor grad, testsituasjonen påvirker testresultatene. I dette studiet gjennomføres til sammen 20 brukbarhetstester. Testene ble gjennomført i to runder på et nettsted for Studentsamskipnaden i Trondheim". Studiet viser at RTA og CTA oppleves forskjellig av testbrukerne, og at opplevelsen av CTA har innvirkning på resultatene. CTA- testdeltagerne brukte lengre tid på å gjennomføre oppgavene og metoden avdekket i tillegg falske brukskvalitetsproblem. Alle testdeltagerne kom med flere negative tilbakemeldinger på CTA, mens det stort sett var positive tilbakemeldinger på RTA metoden. Den negative kritikken av CTA var gjennomgående temaer som; mislikte å bli filmet, dobbel kognitiv belasting, vanskelig å sette ord på tanker, prestasjonsangst, press til å snakke, dårlig tid til oppgaveløsning, vanskelig å holde verbaliseringen gående og tenker annerledes enn de snakker.
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Ebrahimdoost, Yousef. "Computer aided detection of pulmonary embolism (PE) in CTA images." Thesis, Kingston University, 2012. http://eprints.kingston.ac.uk/24027/.
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Pulmonary embolism (PE) is an obstruction within the pulmonary arterial tree and in the majority of cases arises from a thrombosis that has travelled to the lungs via the venous system. Pulmonary embolism (PE) is a fatal condition which affects all age groups and is the third most common cause of death in the US. Computed tomographic angiography (CTA) imaging has recently emerged as an accurate method in the diagnosis of pulmonary embolism. Each CTA scan contains hundreds of CT images, so the accuracy and efficiency of interpreting such a large image data set is complicated due to various PE look-alikes and human factors such as attention span and eye fatigue. Moreover, manual reading and interpreting a large number of slices is time consuming and it is difficult to find all the pulmonary embolisms (PE) in a data set. Consequently, it is highly desirable to have a computer aided detection (CAD) system to assist radiologists in detecting and characterizing emboli in an accurate, efficient and reproducible manner. A computer aided detection (CAD) system for detection of pulmonary embolism is proposed in CTA images. Our approach is performed in three stages: firstly the pulmonary artery tree is extracted in the region of the lung and heart in order to reduce the search area (PE occurs inside the pulmonary artery) and aims to reduce the false detection rate. The pulmonary artery is separated from the surrounding organs by analyzing the second derivative of the Hessian matrix and then a hybrid method based on region growing and a new customized level set is used to extract the pulmonary artery (PA). In the level set implementation algorithm, a new stopping criterion is applied, a consideration often neglected in many level set implementations. In the second stage, pulmonary embolism candidates are detected inside the segmented pulmonary artery, by an analysis of three dimensional features inside the segmented artery. PE detection in the pulmonary artery is implemented using five detectors. Each detector responds to different properties of PE. In the third stage, filtering is used to exclude false positive detections associated with the partial volume effect on the artery boundary, flow void, lymphoid tissue, noise and motion artifacts. Soft tissue between the bronchial wall and the pulmonary artery is a common cause of false positive detection in CAD systems. A new feature, based on location is used to reduce false positives caused by soft tissue. The method was tested on 55 data scans (20 training data scans and 35 additional data scans for evaluation containing a total of 195 emboli). The system provided a segmentation of the PA up to the 6th division, which includes the sub-segmental level. Resulting performance gave 94% detection sensitivity with an average 4.1 false positive detections per scan. We demonstrated that the proposed CAD system can improve the performance of a radiologist, detecting 19 (11 %) extra PE which were not annotated by the radiologist.
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Loberg, Johannes, and Miranda Gisudden. "Estimation of Noise and Contrast for CTA of the Brain." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-239916.
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Computed tomography angiography (CTA) of the brain poses challenges on the imaging system; the contrast between blood vessels and surrounding soft tissue is very low, and to render small intricate vessel structures high spatial resolution is needed. Higher precision angiography would facilitate more accurate diagnosis of pathological conditions. The aim of this work was to analyze the factors which contribute to the image quality in cerebrovascular imaging contexts and make a comparison between state-of-the-art energy-integrating and photon counting CT systems. A geometrical model was devised to mimic the conditions of cerebral angiography. Different parameters and detectors were used to reconstruct images of a spherical head phantom. Compton noise was added to several image acquisitions after a Monte Carlo study was used to estimate the scatter to primary ratio (SPR) with a spherical phantom. The images were evaluated qualitatively and quantitatively. A real phantom was scanned with an experimental photon counting detector and compared with the simulated approach. The work resulted in qualitative reconstructed images, a decrease in SPR when introducing air gaps and improved resolution but worsened contrast as a result of smaller detector sizes. The SPR was shown to be higher in cone-beam geometry than fan-beam geometry. Electronic noise present with energy integrating detectors was shown to degrade image quality significantly in low dose imaging, reducing contrast when imaging vascular-like structures. Photon counting detectors without electronic noise could provide greater image quality and better diagnostic information.
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Blackwood, John Kenneth. "Expanded CTG trinucleotide repeats stimulate homologous recombination in Escherichia coli." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/14991.
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Expanded trinucleotide repeats (TNRs) (e.g. CAG, CTG, CCG) cause 40 different human diseases, however the molecular mechanism underlying the expansion of TNRs is poorly understood. This work describes the integration, in the chromosome of the bacterium Escherichia coli of differently sized CAG and CTG TNRs into the start of the lacZ gene and of a zeocin resistance recombination reporter substrate into the nearby gene, cynX. We show that TNRs stimulate recombination at cynX in a length dependent manner. Furthermore, stimulation of recombination is dependent on TNR orientation with respect to the origin of replication. Experiments indicate that zeocin recombination is reduced in E. coli mutants for double strand break repair (recA and recB); but not for gap repair (recR). TNR induced stimulation of recombination is shown to be independent of the DNA hairpin nuclease SbcCD arguing against any role of secondary structure formed by TNRs. The formation of DSBs by TNRs is investigated using pulse field gel electrophoresis (PFGE). Since reversed replication forks can initiate homologous recombination (HR), this thesis investigates the possibility that TNRs lead to replication form reversal (RFR). We test this hypothesis by assaying for HR using zeocin recombination reporter substrates positioned proximal and distal with respect to the origin of replication. We show that TNR induced HR is lower at the distal site. Furthermore, the protein UvrD is known to be essential for RFR in certain replication mutants. TNR dependent stimulation of HR is lost in uvrD mutants. Both these data support the hypothesis that TNRs can cause RFR.
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Goletto, Valérie. "Synthèse et caractérisation d'organosilices mésostructurées à porosité périodique." Paris 6, 2002. http://www.theses.fr/2002PA066490.
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Arnold, Julia. "The performance persistence, flow and survival of systematic and discretionary Commodity Trading Advisors (CTAs)." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/12647.
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This thesis studies the performance, performance persistence, survival and flow of Commodity Trading Advisors, also known as CTAs or Managed Futures Funds. One of the main contributions of this thesis is the novel classification of CTA strategies. This is obtained by hand-collecting information frequently by directly contacting the funds in the database. I thus identify two main trading styles: Systematic and Discretionary CTAs which are the main focus of this thesis. I further separate Systematic CTAs into trend-followers with differing trading horizon. This novel dataset allows me to reconsider many hitherto studied issues in the CTA space with an application to these sub-strategies. The first section investigates the differences in mortality between Systematic and Discretionary CTAs, over the longest horizon than of any in the literature. A detailed survival analysis over the full range of CTA strategies is provided. Systematic CTAs have a higher median survival than Discretionary CTAs, 12 vs. 8 years. I hand collect information on reasons for exit from the database. I propose new filters that will better identify real failures among funds in the graveyard database. Separating graveyard funds into real failure I re-examine the attrition rate of CTAs. The real failure rate is 11.1%, lower than the average yearly attrition rate of 17.3% of CTAs. The effect of various covariates including several downside risk measures is investigated in predicting CTA failure. Controlling for performance, HWM, minimum investment, fund age and lockup, funds with higher downside risk measures have a higher hazard rate. Compared to other downside risk measures, the volatility of returns is less able to predict failure. Funds that receive larger inflows are able to survive longer than funds that do not. Large Systematic CTAs have the highest probability of survival. The second part studies the performance and performance persistence of Systematic and Discretionary CTAs. Controlling for biases, after fees the average CTA is able to add value. These results are strongest for large Systematic CTAs. I extend the sevenfactor model of Fung-Hsieh (2004a) and find that this model is better able to explain the returns of Systematic rather than Discretionary CTAs. I find three structural breaks in the risk loadings of CTAs different to hedge fund breaks: September 1998, March 2003 and July 2007. Using these breaks I show that systematic CTAs were able to deliver significant alpha in every sub-period. I also find evidence of significant performance persistence. However, these findings are heavily contingent on the strategy followed: the persistence of Discretionary CTAs is driven by small funds whereas large funds drive the performance persistence of Systematic funds. These results have important implications for institutional investors who face capital allocation constraints. They also suggest that contrary to the previous findings, the CTA industry does not appear to be heading towards zero alpha. The final section looks at the relationship between fund-flows and performance. Investors chase past performance, the fund- flow -performance is significant and concave for some strategies. Although there is some long-term performance persistence of Systematic funds with the highest inflows, there is no smart money effect in the CTA literature. I find no evidence of capacity constraints among Systematic CTAs. Investors are thus not able to smartly allocate funds to future best performers and take full advantage of the liquidity that CTAs offer.
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Gasnier, Erwan. "Expansion de triplets CTG et arrêt prolifératif précoce des myoblastes DM1." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2012. http://tel.archives-ouvertes.fr/tel-00829312.
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La dystrophie myotonique de type I est la pathologie neuromusculaire la plus répandue chez l'adulte. Elle est caractérisée par une atteinte multisystémique plus ou moins prononcée en fonction de l'extension des répétitions CTG, mutation à l'origine de l'atteinte. Le muscle squelettique est particulièrement touché avec un phénomène de myotonie ainsi qu'une atrophie. Les myoblastes, à l'origine de la formation des muscles et de leur régénération potentielle, présentent, chez les patients DM1, une capacité proliférative limitée par rapport à des myoblastes issus d'individus sains. C'est l'activation précoce de la voie p16 qui est à l'origine de cette sénescence prématurée des cellules DM1. Les mécanismes conduisant à ce phénotype sont néanmoins inconnus. Au cours de cette étude, nous avons tenté de décrypter une partie de ces mécanismes et notamment les liens potentiels entre les expansions CTG, la sensibilité au stress oxydatif et l'activation précoce de la voie p16 conduisant à la sénescence des myoblastes DM1
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Fromm, Christian [Verfasser]. "Spectral Evolution in Blazars : the Case of CTA 102 / Christian Fromm." Bonn : Universitäts- und Landesbibliothek Bonn, 2013. http://d-nb.info/1044868465/34.
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Zantl, Christiane Susan. "Bedeutung verschiedener CTG-Parameter für die ante- und intrapartale fetale Zustandsdiagnostik." kostenfrei, 2008. http://mediatum2.ub.tum.de/doc/655148/655148.pdf.
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Defosse, Tatiana. "Développement d'outils moléculaires standardisés pour les espèces levuriformes du clade CTG." Thesis, Tours, 2017. http://www.theses.fr/2017TOUR3803/document.
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Parmi les espèces de levures du clade CTG, certaines sont responsables de candidoses tandis que d’autres présentent des potentiels en biotechnologie. Depuis quelques années, nous assistons à une intensification des recherches sur ces levures. Cependant, leur code génétique particulier a ralenti la mise au point d’outils génétiques pour la plupart d’entre elles. Cette thèse vise à développer des outils moléculaires standardisés pour un grand nombre d’espèces de levures du clade CTG. Nous avons d’abord conçu des vecteurs d’expression adaptés à l’espèce M. guilliermondii. Par la suite, nous avons caractérisé le gène de résistance à l’acide mycophénolique IMH3.2 afin de l’utiliser comme marqueur de sélection lors de la transgénèse d’espèces du clade CTG. Enfin, nous avons mis au point une série de vecteurs permettant la manipulation génétique de ces espèces. Ce travail a conduit à la conception d’une large gamme d’outils utilisable dans un grand nombre de ces levures, pré-requis essentiel aux futurs recherches en mycologie médicale et au développement de stratégies de biologie synthétiqueThe fungal CTG clade includes well-known yeasts of clinical importance and/or biotechnological potential. Thus, albeit being intensively studied over the last 30 years, their uncommon genetic code precludes the use of the widely available markers and reporter systems for genetic approaches in these microorganisms. We provide here a toolbox to genetically manipulate a wide range of CTG clade species. Firstly, we developed a new series of versatile controllable expression vectors for M. guilliermondii. After, we characterized MPA-resistant gene IMH3.2 et used it as a drug resistance marker in several yeast species. Finaly, we provide a molecular toolbox suitable to genetically manipulate a broad range of prominent species from the CTG clade. This versatile toolkit represents a new starting point for successful developments of research in medical mycology in the CTG clade but also will expedite synthetic biology strategies in these microorganisms for biotechnological applications
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van, den Bergh-Mehner Stefanie. "Anlagestrategien für Pensionsvermögen im Rahmen von Contractual Trust Arrangements." Doctoral thesis, Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-81815.
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Die vorliegende Arbeit behandelt die Anlage von Pensionsvermögen im Rahmen von Contractual Trust Arrangements. Es wird untersucht, welche Anlagestrategien sich unter Berücksichtigung bilanzieller, verpflichtungs- und vermögensseitiger Rahmenbedingungen zur Anlage von Pensionsvermögen eignen. Anhand eines geeigneten Anlagemodells für Pensionsvermögen und der Durchführung einer stochastischen Simulation wird analysiert, welchen Einfluss unterschiedliche Anlagestrategien auf die Entwicklung des Pensionsvermögens haben. Die Arbeit geht zunächst auf den Hintergrund der betrieblichen Altersversorgung und Contractual Trust Arrangements in Deutschland ein. Zur Abbildung der Verpflichtungsseite und der Mitarbeiterstruktur des Unternehmens wird unter Einbezug aktuarischer Ansätze ein Mitarbeitermodell entwickelt. Das in der Arbeit entwickelte Portfoliomodell integriert die Verpflichtungs- und Vermögensseite und zeigt, wie das Vermögen zur Deckung leistungsorientierter Zusagen zur betrieblichen Altersversorgung unter Einbezug der Unternehmensperspektive mit Hilfe dynamischer Risikonebenbedingungen geeignet angelegt werden kann.
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Marcomini, Jéssica Arab. "Estudo da possibilidade de detecção da matéria escura com telescópios Cherenkov." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/76/76131/tde-20072015-093902/.
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A existência de matéria escura é sustentada pela observação de efeitos gravitacionais sobre a matéria comum. A partir desses efeitos, com medidas de curvas de rotação e lentes gravitacionais, é possível calcular a densidade de matéria escura necessária para causa-los. Para descrever o comportamento observado, foram criados alguns modelos teóricos, porém a natureza das partículas que constituem matéria escura continua desconhecida. Determinar propriedades como massa e seção de choque da possível partícula de matéria escura é fundamental para o entendimento da natureza de seus efeitos sobre matéria bariônica. No âmbito experimental, os Telescópios Cherenkov medem a radiação gama proveniente do cosmo com energia entre GeV —TeV de forma que uma possível interação (como exemplo a aniquilação de partículas de matéria escura) poderia ter seu resultado final de raios gama detectado em um dos experimentos de observação indireta. Neste trabalho de mestrado analisamos os conceitos de matéria escura a partir de um modelo específico de partículas WIMPs, o neutralino. Estudamos galáxias anãs esferoidais como possíveis fontes do sinal de raios gama proveniente da aniquilação de neutralinos. Para o entendimento dos cálculos, reproduzimos os resultados de dois experimentos importantes para a área, pertencentes aos telescópios VERITAS e MAGIC, validando as implementações realizadas. Estudamos também galáxias anãs esferoidais observadas pelo experimento FERMI-LAT para as quais limites superiores de fluxo foram determinados. Fizemos uso dessas medidas e extrapolamos os espectros de energias para o intervalo a ser observado pelo CTA. Utilizando curvas de sensitividade realistas para uma possível configuração do CTA, determinamos a potencialidade de detectação de matéria escura pelo CTA de 18 fontes estudados pelo FERMI-LAT. A partir dos resultados obtidos com a simulação do Observatório, podemos concluir quais fontes proporcionam melhores avanços para as pesquisas envolvendo matéria escura com o modelo escolhido.The existence of dark matter is sustained by the observation of its gravitational efects on ordinary matter. By studying these efects, with rotation curves and gravitational lensing measurements, it is possible to calculate the dark matter density necessary to cause them. Theoretical models were created to describe the observed behavior, however the nature of the constituent particles is still unknown. Determining the particles\' properties such as mass and cross section is fundamental for the understanding of the nature of its efects on baryonic matter. On the experimental scope, Cherenkov Telescopes measure the gamma radiation coming from the cosmo with an energy between GeV —TeV making it possible for an interaction to have its final product detected in one of these experiments. In this dissertation, we present an analysis of dark matter concepts considering a specific model of WIMPs particles, represented by the neutralino. We studied dwarf spheroidal galaxies as possible gamma-ray flux sources originated from the neutralino annihilation. We reproduced the results on annihilation cross section of two important experiments for this particular field (VERITAS and MAGIC), validating the codes implemented. This was perfomed with the objective of understanding the calculus involved. We studied dwarf spheroidal galaxies observed by the FERMI-LAT experiment for which upper limits flux were determined. We used these measurements and extrapolated the energy spectrum to the one to be observed by CTA. With realistic sensitivity curves for a possible CTA configuration, we determined the potencial for a dark matter detection for 18 sources studied by FERMI-LAT. With the results obtained with the Observatory simulation, we were able to conclude which of these sources represent improvements for dark matter researches with the specific model described.
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Wenger, Roland Hugo. "Platelet molecular biology : cloning and characterisation of the platelet-specific genes CTAP-III and GPIba /." Bern, 1990. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Tonegutti, Claudio Antonio. "Transferencia de fase de M-Alcoxifenois da agua para carvão ativo e micelas de CTAB." [s.n.], 1990. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249103.
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Orientador : Pedro L.O. VolpeDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Ananthakrishnan, Shilpa. "P-type ATPases in Mycobacterium tuberculosis." Digital WPI, 2009. https://digitalcommons.wpi.edu/etd-theses/1200.
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"Tuberculosis is a deadly disease caused by bacteria of the genus Mycobacterium. One-third of the world’s population is infected with Mycobacterium tuberculosis. Two million these deaths occur each year in immunocompromised AIDS patients. M. tuberculosis has co-evolved with humans for many thousands of years. The bacillus has developed tactics to overcome the immune defense system and multiply in the macrophage. At the interface of the host and pathogen interactions, there is an interchange of metals and electrolytes. The host on one hand reduces the availability of metals essential for pathogen survival, like manganese and iron, in the macrophage and increases potassium ions which reduces pH in the phagolysosome. The host also generates Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS), to create toxic affects through interactions with metals and metalloproteins. M. tuberculosis copes with the hostile environment in the macrophage by preventing the acidification of the phagolysosome, secreting antioxidant enzymes such as alkylhydroperoxidase (AhpF) and peroxiredoxin (AhpC), superoxide dismutase, SodA and SodC, and catalase KatG through the SecA system. M. tuberculosis contains 28 metal transporters, among them there are 12 unique P-type ATPases. This is an unusually high number of P-type ATPases in an organism. These ATPases transport several monovalent and divalent metals (Cu+, Cu2+, Ag+, Zn2+, Na+, K+, Ca2+, Cd2+, Pb2+, Mn2+, Mg2+, and Co2+) across biological membranes, using energy from ATP hydrolysis. Our analysis has revealed that these P-type ATPases have homologs in other intracellular symbiotic/pathogenic bacteria and certain chemolithotrophic archaea and bacteria. A corelation can hence be drawn among these pumps and the capability of surviving in noxious environments and coping with adverse redox conditions. Possible substrates were identified by determining the consensus sequences in different helices of these ATPases. However, out of the 12 P-type ATPases confirmed, transported substrate could be postulated for four of these proteins; CtpA, CtpB, CtpV and KdpB. Using bioinformatic approaches we have characterized the possible genetic environment of these genes. The transmembrane regions were analyzed for consensus sequences and the N-terminals and C-terminals were scrutinized for metal binding domains, and we were able to categorize these ATPases into P1 type and P2 type ATPases. In an attempt to determine the substrate specificity, two of these ATPases (CtpC and ctpG) were cloned and transformed into Escherichia coli cells. Cells expressing CtpC were grown in different concentrations of metals and pHs. In these experiments CtpC was found to show an interaction with copper and cadmium. Pure protein was obtained by His-tag purification and para-Nitro Phenol Phosphatase (pNPPase) assay was performed with different metals, it was found that copper and zinc activated the phosphatase activity of the enzyme; and cobalt and manganese were inhibitory. Inhibition of the pNPP assay could mean that there would be activation in the ATPase assay, meaning that cobalt and manganese could be possible substrates to this enzyme. "
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van, den Bergh-Mehner Stefanie. "Anlagestrategien für Pensionsvermögen im Rahmen von Contractual Trust Arrangements." Doctoral thesis, Universitätsbibliothek Chemnitz, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-79062.
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Die vorliegende Arbeit behandelt die Anlage von Pensionsvermögen im Rahmen von Contractual Trust Arrangements. Es wird untersucht, welche Anlagestrategien sich unter Berücksichtigung bilanzieller, verpflichtungs- und vermögensseitiger Rahmenbedingungen zur Anlage von Pensionsvermögen eignen. Anhand eines geeigneten Anlagemodells für Pensionsvermögen und der Durchführung einer stochastischen Simulation wird analysiert, welchen Einfluss unterschiedliche Anlagestrategien auf die Entwicklung des Pensionsvermögens haben. Die Arbeit geht zunächst den Hintergrund der betrieblichen Altersversorgung und Contractual Trust Arrangements in Deutschland ein. Zur Abbildung der Verpflichtungsseite und der Mitarbeiterstruktur des Unternehmens wird unter Einbezug aktuarischer Ansätze ein Mitarbeitermodell entwickelt. Das in der Arbeit entwickelte Portfoliomodell integriert die Verpflichtungs- und Vermögensseite und zeigt, wie das Vermögen zur Deckung leistungsorientierter Zusagen zur betrieblichen Altersversorgung unter Einbezug der Unternehmensperspektive mit Hilfe dynamischer Risikonebenbedingungen geeignet angelegt werden kann.
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Gomes, Kerolin Aparecida Alves. "Estudo do efeito do ph e da adsorção de surfactante catiônico na redispersão de nanocristais de celulose em água." Universidade Estadual de Ponta Grossa, 2018. http://tede2.uepg.br/jspui/handle/prefix/2539.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A utilização de materiais ambientalmente corretos, de fonte renovável, assim como a celulose, tem se apresentado como assunto de interesse para muitos pesquisadores. Neste trabalho os nanocristais de celulose (NCC) foram extraídos a partir da celulose microcristalina comercial (CMC) com posterior ajuste de pH e modificação superficial com o surfactante catiônico brometo de cetil trimetil amônio (CTAB), objetivando-se realizar a secagem dos NCC e posterior redispersão em água. Para tanto, foram estudadas as influências dos procedimentos de diálise, da faixa de pH, da modificação superficial e também da técnica de secagem sobre a estabilidade coloidal e também sobre a distribuição de tamanhos de partículas. Três técnicas de secagem foram estudadas: (1) secagem em estufa, (2) secagem por liofilização e (3) secagem por spray drying. Na secagem em estufa houve a formação de aglomerados indissolúveis impedindo a redispersão dos NCC, nesta técnica foi avaliado principalmente o efeito do ajuste de pH, observando-se que para condições ácidas de pH ocorre a degradação dos NCC. Na secagem por liofilização foi possível redispersar os NCC em água, porém não foi obtido um material seco estável, pois ocorreu a dessorção da água. Observou-se também que para adições maiores do contra-íon +, obtiveram-se melhores resultados de redispersão quanto à distribuição de tamanho de partículas. Na técnica de secagem por spray drying foi testada a influência do surfactante sobre a redispersão. A adsorção do surfactante catiônico à superfície dos NCC foi confirmada pela técnica de espectroscopia no infravermelho por transformada de Fourier (FTIR). Ficou demonstrado que com a adição de 1% de surfactante às suspensões de NCC é possível redispersá-las obtendo características muito próximas as das suspensões antes do processo de secagem, no entanto, observou-se perda da estabilidade coloidal para algumas amostras após a redispersão. As técnicas de microscopia eletrônica de varredura (MEV), difração de raios X (DRX), análise termogravimétrica (ATG) e análise reológica foram usadas para caracterizar o material obtido na secagem por spray drying, que foi determinada como a melhor técnica de secagem. A morfologia das partículas apresentou-se no formato esférico, com a formação de aglomerados. Foram obtidos elevados índices de cristalinidade para as amostras com adsorção do surfactante CTAB, porém com reduzida estabilidade térmica. A avaliação da viscosidade cinemática indicou um comportamento pseudoplástico para as suspensões do NCC e um aumento na viscosidade das amostras após a secagem e redispersão indicou a formação de aglomerados
The use of environmentally friendly materials from renewable sources, as well as cellulose, has been presented as a subject of interest to many researchers. In this work the cellulose nanocrystals (CNC) were extracted from commercial microcrystalline cellulose (CMC) with subsequent pH adjustment and surface modification with the cationic surfactant cetyl trimethyl ammonium bromide (CTAB), aiming to dry the CNC and rehydrate them in water. The influence of dialysis procedure, pH range, surface modification and drying technique on colloidal stability and particle size distribution were studied. Three drying techniques were studied: (1) oven drying, (2) drying by lyophilization and (3) spray drying. The oven drying process showed the formation of indissoluble agglomerates preventing the redispersion of CNC, in this technique the effect of the pH adjustment was evaluated, and it was observed that for acidic pH conditions the degradation of CNC occurs. On drying by lyophilization it was possible to redisperse the CNC in water, but it was not possible to obtain a stable dry material, as water desorption occurred. It was also observed that for larger additions of the counterion +, better particle size distribution results were obtained for the redispersed suspensions. The influence of the surfactant on redispersion was tested in the spray drying drying technique. The adsorption of the cationic surfactant to the surface of the CNC was confirmed by the Fourier transform infrared spectroscopy (FTIR) technique. It has been shown that with the addition of 1% surfactant to the CNC suspensions it is possible to redisperse them obtaining characteristics very close to those of the suspensions prior to the drying process, however, loss of colloidal stability has been observed for some samples after redispersion. Scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and rheological analysis were used to characterize the material obtained by spray drying, which was determined as the most suitable drying technique. The particles were presented with a spherical morphology and with the formation of agglomerates. High crystallinity indexes were obtained for samples with adsorption of CTAB surfactant, but with low thermal stability. The kinematic viscosity assessment indicated a pseudoplastic behavior for the CNC suspensions and an increase in the viscosity of the samples after drying and redispersion indicated the formation of agglomerates.
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Di, Piano Ambra. "Detection of short Gamma-Ray Bursts with CTA through real-time analysis." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/19962/.
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With respect to the current IACTs, CTA will cover a larger energy range (~20 GeV - 300 TeV) with one order of magnitude better sensitivity. The facility will be provided with a real-time analysis (RTA) software that will automatically generate science alerts and analyse data from on-going observations in real-time. The RTA will play a key role in the search and follow-up of transients from external alerts (i.e. from on-space gamma-ray missions, observatories operating at other energy bands or targets of opportunity provided by neutrinos and gravitational waves detectors). The scope of this study was to investigate the ctools software package feasibility for the RTA, adopting a full-field of view maximum likelihood analysis method. A prototype for the RTA was developed, with natively implemented utilities where required. Its performance was extensively tested for very-short exposure times (far below the lower limit of current Cherenkov science) accounting for sensitivity degradation due to the non-optimal working condition expected of the RTA. The latest IRFs, provided by CTA Performance, were degraded via effective area reduction for this purpose. The reliability of the analysis methods was tested by means of the verification of Wilks' theorem. Through statistical studies on the pipeline parameter space (i.e. minimum required exposure time), the performance was evaluated in terms of localization precision, detection significance and detection rates at short-timescales using the latest available GRB afterglow templates for the source simulation. Future improvements involve further tests (i.e. with an updated population synthesis) as well as post-trials correction of the detection significance. Moreover, implementations allowing the pipeline to dynamically adapt to a range of science cases are required. Prospects of forthcoming collaboration may involve the integration of this pipeline within the on-going work of the gamma-ray bursts experts of CTA Consortium.
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Dunlop, Thomas William. "The isolation and characterisation of mouse genes containing CAG/CTG trinucleotide repeats." Thesis, University of Glasgow, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363168.
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Hütten, Moritz. "Prospects for Galactic dark matter searches with the Cherenkov Telescope Array (CTA)." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2017. http://dx.doi.org/10.18452/17766.
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Die vorliegende Arbeit beschreibt einen semi-analytischen Ansatz zur Modellierung der Dichteverteilung von DM im Galaktischen Halo. Aus den verschiedenen Substrukturmodellen wird die γ-Strahlungsintensität, welche die Erde erreicht, berechnet. Eine Spannbreite plausibler γ-Strahlungsintensitäten aufgrund der Paarvernichtung Galaktischer DM wird vorgeschlagen, welche die Vorhersagen verschiedener früherer Studien umfasst, und es werden die durchschnittlichen Massen, Abstände und ausgedehnten Strahlungsprofile der γ-strahlungsintensivsten DM-Verdichtungen berechnet. Schließlich werden die DM-Modelle für eine umfassende Berechnung der Nachweismöglichkeit Galaktischer Substrukturen mit CTA verwendet. Die instrumentelle Sensitivität zum Nachweis der γ-strahlungsintensivsten DM-Substruktur wird für eine mit CTA geplanten großflächigen Himmelsdurchmusterung außerhalb der Galaktischen Ebene berechnet. Die Berechnung wird mit CTA Analyse- Software und einer Methode durchgeführt, welche auf einer Likelihood beruht. Eine alternative, ebenfalls Likelihood-basierte Analysemethode wird entwickelt, mit welcher DM-Substrukturen als äumliche Anisotropien im Multipolspektrum des Datensatzes einer Himmelsdurchmusterung nachgewiesen werden können. Die Analysen ergeben, dass eine Himmelsdurchmusterung mit CTA und eine anschließende Suche nach γ-Strahlung von DM-Substrukturen Wirkungsquerschnitte für eine Paarvernichtung in der Größenordnung von (σv) > 1 × 10−24 cm3 s−1 für eine DM-Teilchenmasse von mχ ∼ 500 GeV auf einem Vertrauensniveau von 95% ausschließen kann. Diese Sensitivität ist vergleichbar mit Langzeitbeobachtungen einzelner Zwerggalaxien mit CTA. Eine modellunabhängige Analyse ergibt, dass eine Himmelsdurchmusterung mit CTA Anisotropien im diffusen γ-Strahlungshintergrund oberhalb von 100 GeV für relative Schwankungen von CPF > 10−2 nachweisen kann.In the current understanding of structure formation in the Universe, the Milky Way is embedded in a clumpy halo of dark matter (DM). Regions of high DM density are expected to emit enhanced γ-radiation from the DM relic annihilation. This γ-radiation can possibly be detected by γ-ray observatories on Earth, like the forthcoming Cherenkov Telescope Array (CTA). This dissertation presents a semi-analytical density modeling of the subclustered Milky Way DM halo, and the γ-ray intensity at Earth from DM annihilation in Galactic subclumps is calculated for various substructure models. It is shown that the modeling approach is able to reproduce the γ-ray intensities obtained from extensive dynamical DM simulations, and that it is consistent with the DM properties derived from optical observations of dwarf spheroidal galaxies. A systematic confidence margin of plausible γ-ray intensities from Galactic DM annihilation is estimated, encompassing a variety of previous findings. The average distances, masses, and extended emission profiles of the γ-ray-brightest DM clumps are calculated. The DM substructure models are then used to draw reliable predictions for detecting Galactic DM density clumps with CTA, using the most recent benchmark calculations for the performance of the instrument. A Likelihood-based calculation with CTA analysis software is applied to find the instrumental sensitivity to detect the γ-ray-brightest DM clump in the projected CTA extragalactic survey. An alternative Likelihood-based analysis method is developed, to detect DM substructures as anisotropies in the angular power spectrum of the extragalactic survey data. The analyses predict that the CTA extragalactic survey will be able to probe annihilation cross sections of ⟨σv⟩ > 1 × 10−24 cm3 s−1 at the 95% confidence level for a DM particle mass of mχ ∼ 500 GeV from DM annihilation in substructures. This sensitivity is compatible with long-term observations of single dwarf spheroidal galaxies with CTA. Independent of a particular source model, it is found that the CTA extragalactic survey will be able to detect anisotropies in the diffuse γ-ray background above 100 GeV at a relative amplitude of CP_F > 10−2.
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Ion, Adina Izabela. "Computer aided detection and measurement of peripheral arterial diseases from CTA images." Thesis, Kingston University, 2013. http://eprints.kingston.ac.uk/26273/.
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Peripheral Arterial Disease (pAD) afflicts more than 2.7 million people in the U.K. per year, and it is projected to increase rapidly within the current decade. PAD is a product of obstruction (stenosis or occlusion) of vessels feeding the body's extremities, and it is most often encountered in the lower extremities. Treatment of the disease is dependent on the specific anatomic segments afflicted, the degree of stenosis and its length. A common technique for imaging PAD is Computed Tomography-Angiography (CTA). The acquired CTA images are then investigated by a radiologist for disease assessment. However due to the large size of the PAD CTA datasets (1000-2000 slices) the radiologist's examination is time consuming and laborious. This project brings a contribution to the investigation of PAD in CTA datasets by the development of a tool for the radiologist, a fully automatic system for the detection and measurement of PAD, as currently there are no such systems efficacious for the disease. The proposed system is comprised of two components: a Computer Aided Detection (CAD) component and a Computer Aided Measurement (CAM) component. The CAD component is designed for artery segmentation and stenosis detection. The stage of artery segmentation is accomplished by using a 3D region growing method and an innovative 3D fast morphology operation. CAD methodologies commonly employ morphological operations as a tool in the segmentation process, along with extended series of CTA images. This large dataset requires careful attention to be paid towards optimizing the computational process in terms of time efficiency. In order to meet this goal, an optimized morphology algorithm is presented, which reduces the computation time by a factor of 10. A skeletonization based centreline technique is applied on the detected artery, and it then provides the basis for the measurement stage. Orthogonal planes to the centreline are used in order to obtain cross sectional images. The artery profile is then built based on vessel areas measured in the cross sectional images and an automated process of stenosis detection is performed. The CAM component of the system accurately measures and quantifies the stenosis and overcomes the challenge brought by the partial volume effect. In this respect, a hybrid method for partial volume correction is employed locally, on the candidate areas of stenosis detected by the CAD component, based on Maximum a Posterior (MAP) and Markov Random Field (MRF) expectation maximization method. The CAD-CAM system has been successfully implemented and applied on phantom and patient data (twenty data sets from The University Hospital of Lausanne (CHUV)) and the evaluation was carried out through the visual judgment of two experienced radiologists. Within the CAD component, the artery segmentation was evaluated and a total of 15 peripheral arterial trees were correctly extracted. The proposed stenosis detection method was evaluated on 525 arterial segments (each dataset was partitioned into 35 segments) from which 132 exhibited stenosis caused by soft plaque. The system achieved a sensitivity of 88% and a specificity of 96%. The CAM component has been evaluated using phantom data, and the average error of the diameter measurement was 8%.
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Gil, Paulo Guilherme. "Algoritmo para conversão automática de modelos SAN GTA para modelos SAN CTA." Pontifícia Universidade Católica do Rio Grande do Sul, 2013. http://hdl.handle.net/10923/1642.
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Previous issue date: 2013This work presents a formalism for modeling systems called Stochastic Automata Networks (SAN), SAN formalism aims to increase the abstraction’s level and provides a sophisticated alternative model to the tadicional formalism of Markov Chains (MC). SAN uses both Classical (CTA) and Generalized Tensor Algebra (GTA) to simplify the matrix of transitions between states of the model. Despite all models described with GTA having at least one equivalent model described using CTA, and that the solution of certain models based on CTA could be faster than the equivalent GTA based model, this dissertation proposes an algorithm for translating a model described in GTA into the equivalent model described in CTA. It is expected that some models described using functions (using GTA) could be solved more quickly or taking less memory through the solution of its CTA-converted model.
Este trabalho apresenta o formalismo para modelagem de sistemas chamado Redes de Autômatos Estocásticos (SAN). O formalismo SAN tem o objetivo de aumentar o nível de abstração e oferece uma alternativa de modelagem mais sofisticada do que a proporcionada pelas tradicionais Cadeias de Markov (MC). Este formalismo utiliza a álgebra tensorial clássica (CTA) e geralizada (GTA) para simplificar a matriz das transições entre os estados do modelo. Embora todos os modelos SAN descritos utilizando GTA possuam pelo menos um modelo equivalente descrito utilizando CTA, e que a solução de certos modelos utilizando CTA possa ser mais rápido que o modelo equivalente que utiliza GTA, este trabalho propõe um algoritmo para traduzir um modelo descrito em GTA para o modelo equivalente descrito em CTA. Espera-se com isto permitir que um modelo descrito utilizando funções (usando GTA) possa ser resolvido mais rapidamente ou ocupando menos memória através da solução de seu modelo convertido para CTA.
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Salazar, Gonz��lez Claudia. "Pasteurizaci��n con microondas de n��ctar de guayaba: estabilidad fisicoqu��mica, microbiol��gica y sensorial." Thesis, Universidad de las Am��ricas Puebla, 2011. http://catarina.udlap.mx/u_dl_a/tales/documentos/mca/salazar_g_c/.
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La guayaba es una fruta tropical altamente perecedera. Sus atributos de calidad se deterioran en un tiempo corto, por lo que tiene que ser procesada en una variedad de productos como el n��ctar de guayaba. Los n��ctares de frutas a menudo se pasteurizan para extender su vida ��til; sin embargo pueden generarse sabores a cocido. Diversos estudios han reportado la factibilidad del calentamiento por microondas para el tratamiento de alimentos l��quidos. Por esta raz��n, el objetivo de este trabajo fue evaluar el efecto de la pasteurizaci��n con microondas sobre las propiedades fisicoqu��micas, microbiol��gicas y sensoriales de n��ctar de guayaba. Para llevar a cabo este estudio, se estableci�� la formulaci��n del n��ctar de guayaba de acuerdo con las especificaciones del Codex Alimentarius (1985) y la aceptaci��n sensorial del producto. Con la formulaci��n elegida, se elabor�� un n��ctar y se determin�� su pH, contenido de vitamina C, acidez titulable, actividad de la enzima pectinmetilesterasa (PME), color, propiedades reol��gicas y cuenta total de microorganismos(cont.) As�� tambi��n, se determinaron los par��metros cin��ticos (D y z) de inactivaci��n t��rmica de la pectinmetilesterasa a 60, 65 y 70 ��C. El n��ctar fresco se trat�� por calentamiento en un sistema de microondas por lotes (2450 MHz) a 90 ��C usando dos niveles de potencia (500 y 950 W) y tiempos de retenci��n preestablecidos (9 y 11 s, respectivamente). A las muestras tratadas a 500 y 950 W se les denominaron como MW500 y MW950, respectivamente. Las condiciones de pasteurizaci��n fueron determinadas en funci��n de la inactivaci��n de la enzima PME. Los n��ctares tratados con microondas se almacenaron a 4 ��C y a los 0, 4, 8 y 12 d��as de almacenamiento se evaluaron en cuanto a sus propiedades fisicoqu��micas y microbiol��gicas. Adem��s, al octavo d��a de almacenamiento se realiz�� una evaluaci��n sensorial para conocer la aceptabilidad general del producto y para detectar diferencias entre el n��ctar fresco y el n��ctar pasteurizado con microondas
(cont.) Los resultados obtenidos se compararon con los de n��ctares pasteurizados en un Intercambiador de Calor de Placas ICP (90 ��C, 0.8 L/min) que fueron almacenados a 4 ��C durante 12 d��as. Se obtuvieron valores de D75 ��C= 4.74 min y z= 5.1 ��C para la enzima PME en n��ctar de guayaba. Los resultados mostraron una inactivaci��n de PME del 53-56 % para las muestras tratadas con microondas; el nivel de potencia no tuvo un efecto significativo (p>0.05). La acidez titulable (0.14 % ��cido c��trico) y los grados Brix (15) no cambiaron significativamente (p>0.05) despu��s del tratamiento con microondas mientras que la vitamina C y el pH s�� se vieron afectados. El coeficiente de consistencia (K) disminuy�� de 1.78 a 1.27 Pa*sn para la muestra MW500 mientras que no se observaron cambios para la muestra MW950 (1.78 Pa*sn); el ��ndice de flujo (n) se mantuvo en 0.20-0.21 en todas las muestras
(cont.) No se observaron diferencias con respecto al color de los n��ctares despu��s del calentamiento con microondas (ΔE*=0.69-0.75). Las propiedades fisicoqu��micas y los conteos microbiol��gicos de las muestras tratadas con microondas no mostraron cambios significativos (p>0.05) durante el almacenamiento en refrigeraci��n; la muestra testigo (sin tratamiento) mostr�� cambios en el pH y una disminuci��n del 31 % en el contenido de vitamina C. La actividad enzim��tica se mantuvo constante mostrando un valor promedio de 1.50 x 10-4 U.A.E./mL al d��cimo segundo d��a de almacenamiento. El testigo no mostr�� cambios significativos (p>0.05) en la actividad de enzim��tica durante el almacenamiento, sin embargo, mostr�� un valor promedio de 2.14 x 10-4 U.A.E./mL No se observaron cambios en el par��metro L*(56.01) ni en el par��metro b* (16.96) para la muestra MW500 durante el almacenamiento
(cont.) Las propiedades reol��gicas de las muestras tratadas con microondas no mostraron cambios significativos (p>0.05) durante el periodo de almacenamiento refrigerado. La muestra tratada en el ICP mostr�� una mayor actividad enzim��tica residual (44.4 %) y una mayor diferencia neta de color (ΔE*= 2.12) al d��a 12 del almacenamiento que la muestra MW500, y tuvo mayor estabilidad desde el punto de vista reol��gico. El calentamiento por microondas se considera una tecnolog��a factible para el tratamiento t��rmico de n��ctar de guayaba; la muestra MW500 present�� mejores caracter��sticas de color, mayor estabilidad enzim��tica y reol��gica que las muestras tratadas en un ICP
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Hadri, Ferhat. "Contribution à l'étude de la réduction de la traînée en écoulement turbulent d'une solution de CTAC." Phd thesis, Université de Caen, 2008. http://tel.archives-ouvertes.fr/tel-00464084.
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La réduction de la traînée est un phénomène d'écoulement qui, par la présence de très petites quantités d'additifs (polymères ou tensio-actifs) dans un fluide quelconque, consiste en une réduction significative du frottement à la paroi en régime turbulent. Certaines solutions d'additifs, en interagissant avec la structure de la turbulence conduisent à une réduction du frottement pouvant aller jusqu'à 90 % par rapport au solvant pur. Ceci induit une réduction de la puissance de pompage de l'ordre de 30 %. La réduction de la traînée peut trouver son application dans des systèmes de chauffage et de refroidissement urbains, dans le domaine pétrolier (pipelines), ... Dans ce travail de thèse une contribution à l'étude de ce type d'écoulement a été menée. Une solution réductrice de la traînée à base de « CTAC/NaSal » à faible concentration a été largement explorée. La rhéométrie, la vélocimétrie par images de particules (PIV) et des modèles numériques sont utilisés. Ainsi, les solutions de tensio-actifs ont été caractérisées rhéologiquement. Plusieurs paramètres influençant la réduction de la traînée en conduite ont été étudiés. Le phénomène de glissement à la paroi a été abordé par une étude dans une géométrie de Couette. Enfin, un modèle de comportement rhéologique issu des mesures rhéologiques a été testé par Simulation Numérique Directe (DNS). Les principaux résultats qui ressortent de ce travail montrent que le mécanisme de la réduction de la traînée est conditionné par plusieurs paramètres par contre, le glissement à la paroi n'est pas forcement responsable de la réduction de la traînée.
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Faivre, Valérie. "Étude des propriétés esterolytiques de complexes hydrophobes 2-hydroxymethylbenzimidazole-zn+² en présence de micelles cationiques (CTAB)." Vandoeuvre-les-Nancy, INPL, 1993. http://www.theses.fr/1993INPL008N.
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On décrit la préparation de deux séries de 2-hydroxymethylbenzimidazoles substitués par une chaine n-alkyle (1 a 14 carbones) en position 5(6) (série I) ou 1 (série II) ainsi que la mise au point de la synthèse de nouveaux picolinates de 4-nitrophenyle (série III) porteurs d'un groupe alkoxy hydrophobe de 1 a 18 atomes de carbone. L'activité esterolytique des systèmes ligands I ou II-Zn2+ vis-à-vis des esters actives III en présence de micelles cationiques (CTAB) est comparée à celle d'un système hydrosoluble de même nature. L'étude cinétique montre l'intervention d'un seul complexe actif 2/1 pour la série I, mais de deux complexes actifs 1/1 et 2/1 pour la série II alors qu'en l'absence de micelles n'existe que le complexe 1/1. Le pouvoir esterolytique global de ces complexes est beaucoup plus élevé qu'une solution moléculaire. L'étude plus détaillée d'un ligand I montre sa complexation quasi totale; cependant la constante de vitesse apparente liée au complexe ainsi que les constantes spécifiques rapportées à la pseudo-phase micellaire sont plus faibles qu'en l'absence de micelle. Cette forte diminution de réactivité peut être attribuée à la formation plus difficile du complexe ternaire ligand/-Zn++/ester, intermédiaire dans la réaction d'esterolyse
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Oliveira, Nilda Nazaré Pereira. "Entre o criar, o copiar e o comprar pronto: a criação de instituições de ensino e pesquisa para a consolidação da indústria aeronáutica brasileira (1945-1990)." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/8/8138/tde-07072008-100907/.
Full textAbstract:
A presente tese tem o objetivo de analisar o processo de consolidação da indústria aeronáutica brasileira a partir de três possibilidades de geração de tecnologia para produtos ou processos: o criar, o copiar e o comprar pronto. O \"criar\" significa aqui a opção de desenvolver tecnologias próprias, autóctones, geradas em instituições ou empresas do próprio país e utilizadas em projetos e programas próprios, que garantam, ou possam garantir soberania econômica, política, estratégica. Para o desenvolvimento desse tipo de tecnologia de produtos e/ou processos é fundamental formar pessoal, formar grupos que dêem sustentação aos processos. O \"criar\" também é influenciado por fatores relacionados aos interesses dos países mais ricos. O \"copiar\" envolve uma forma de produzir que o Brasil já tinha experimentado na indústria de construção aeronáutica, com o exemplo das fábricas de aviões criadas pelo governo, na primeira metade do século XX, que produziam \"sob licença\", mas é uma forma de produzir que o Brasil já experimentava também em outras indústrias que demandam alguma \"tecnologia\". Muitas vezes, \"copiar\" está associado às \"caixas pretas\", sendo que, nesse caso o país não é o dono da \"caixa preta\". Esse tipo de produção pode ser interessante para países que não almejam um real desenvolvimento tecnológico e que servem como base de produção por possuírem mão-de-obra barata, ou incentivos fiscais, ou matéria-prima abundante, ou todas as condições juntas. Finalmente o \"comprar pronto\", é sempre a opção mais rápida, mais imediata, aquela a ser tomada por qualquer país, instituição, empresa ou grupo que não pode esperar por nenhuma das anteriores. É também a opção que deixará o país, instituição, empresa ou grupo mais empobrecido, do ponto de vista do desenvolvimento tecnológico. Pois estará adquirindo um \"produto\", seja ele um bem ou um processo do qual, uma vez cumprida sua função, seu tempo de uso, não restará nada. No caso específico da indústria aeronáutica, o objetivo é investigar e analisar a motivação, as propostas, as decisões, o planejamento, os encaminhamentos e os 12 resultados do projeto de reconstrução da indústria aeronáutica brasileira promovida por um grupo de militares da Aeronáutica, a partir da criação do Instituto Tecnológico de Aeronáutica, em 1950 e do Centro Técnico de Aeronáutica, em 1953. O termo \"reconstrução\" é utilizado porque a indústria de construção aeronáutica no Brasil é mais antiga do que esse projeto e, embora as iniciativas anteriores não tenham obtido o mesmo sucesso da EMBRAER, algumas delas já tinham sido incluídas em planejamentos de desenvolvimento nacional. Assim, nesta análise o sucesso da Empresa Brasileira de Aeronáutica, criada em 1969, pode ser compreendido dentro do projeto modernizador das Forças Armadas e da construção do projeto do Brasil Potência, o que justificaria os investimentos governamentais no financiamento da criação e manutenção da empresa, sem os quais sua viabilização e sucesso não seriam possíveis.The purpose of this thesis is to analyze the process of the Brazilian aeronautical industry consolidation out of three perspectives of generating technology for products or processes: creating, copying and buying readymade. \"Creating\" means the choice of developing proper technologies, and \"made in the country\" by national institutions or companies which are used in internal projects and programs that may ensure economic, political and strategic sovereignty. For the development of this type of product and/or process technology, the formation of appropriate personal is basic to create groups that give support for these processes. \"Creating\" is also influenced by factors related to the interests of the richest countries. \"Copying\" means a well-known formula of production that Brazil had already tried in the aeronautical industry construction. As an example, the industry of airplanes created by the government in the first half of the 20th century produced them \"under license\". In addition, it was a form of production that Brazil also tried in some other industries which demanded some \"technology\". Due to the lack of the scientific domain of the \"black boxes\", the countries that are not the technology owner have to bear the disadvantages of \"copying\". This type of production may be interesting for countries that do not have real technological development and serve only as a production base because of their low manpower cost, tax incentives, abundant raw material or all of them together. Finally, \"buying readymade\" is always the fastest and the most immediate choice that can be taken by any country, institution, company or group that cannot wait for any of the two previous perspectives. It is also the option that will contribute more rapidly for the technological impoverishment, considering that the institution acquires some \"product\", either a property or a process, and after its use, nothing of it will remain. In the specific case of the aeronautics industry, the aim is to investigate and to analyze 14 the motivation, the proposals, the decisions, the planning and the results of the reconstruction of Brazilian industry, implemented by an Air Force military group, after the creation of the Technological Institute of Aeronautics (ITA), in 1950 and the Aeroespace Technical Center (CTA), in 1953. The term \"reconstruction\" is employed because the Brazilian aeronautics industry in Brazil is older than this project and, although previous initiatives did not achieve the same success as EMBRAER, some of them had already been included in the national development program. From this point of view, the success of EMBRAER, created in 1969, can be included in the modernizing project of the Armed Forces and in the construction of a \"Brazilian Power\". This idea could justify the governmental investments in the creation and maintenance of an industry, without which its viability and success would not be possible.