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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Estratégias de apoio à captação de estudos clínicos patrocinados

Oliveira, Fernando Araújo Rodrigues de January 2018 (has links)
Os ensaios clínicos ocorrem cada vez mais em uma escala global e as pesquisas patrocinadas vem mudando para as regiões emergentes. A condução desses estudos traz benefícios para centros de pesquisa, pacientes e para o país como um todo. No entanto, a alocação de ensaios clínicos por companhias farmacêuticas multinacionais é um processo complexo determinado por múltiplos fatores e o conhecimento de quais fatores as companhias farmacêuticas valorizam mais ao alocar ensaios clínicos é escasso. Assim, compreender melhor esse processo é essencial para governos e centros de pesquisa que desejam atrair mais ensaios clínicos patrocinados por companhias farmacêuticas multinacionais. O objetivo deste trabalho é apresentar os atributos de centros de pesquisa clínica necessários para melhorar a captação de estudos clínicos patrocinados. Para identificar os fatores considerados determinantes da seleção de centros de pesquisa por patrocinadores e organizações representativas de pesquisa clínica foi desenvolvido um estudo descritivo-exploratório por meio da revisão da literatura através de buscas em bases de dados. As buscas resultaram na seleção de 16 materiais bibliográficos que abordaram a questão seleção de centros de pesquisa. Os fatores considerados mais críticos para a seleção foram disponibilidade de população alvo e capacidade de recrutamento, tempo de start-up e interesse e motivação da equipe do centro. Além disso, a infraestrutura é considerada um pré-requisito que pode inviabilizar a seleção e a qualidade de dados também é muito valorizada. Os custos diretos de execução do ensaio não foram considerados muito importantes, ao contrário dos custos indiretos. A partir do conhecimento dos pré-requisitos e dos fatores determinantes da seleção de um centro para um ensaio clínico multicêntrico patrocinado por companhias farmacêuticas, a Empresa Brasileira de Serviços Hospitalares poderá promover e direcionar os esforços para organizar uma rede de centros de pesquisa que pode ser muito atrativa. / Clinical trials are increasingly occurring on a global scale and sponsored research has been shifting to emerging regions. Conducting these studies brings benefits to research centers, patients, and the country as a whole. However, the allocation of clinical trials by multinational pharmaceutical companies is a complex process determined by multiple factors and the knowledge of what factors pharmaceutical companies value most when allocating clinical trials is scarce. So, better understanding this process is essential for governments and research centers wishing to attract more clinical trials sponsored by multinational pharmaceutical companies. The objective of this work is to present the attributes of clinical research centers necessary to improve the capture of sponsored clinical studies. To identify the factors considered as determinants of the selection of research centers by sponsors and clinical research organizations, a descriptive-exploratory study was developed through the review of the literature through searches in databases. The search resulted in the selection of 16 bibliographic materials that addressed the issue of selection of research centers. The factors considered most critical for center selection were target population availability and recruiting capacity, start-up time, and interest and motivation of the center staff. In addition, infrastructure is considered a prerequisite that can make selection unfeasible and data quality is also highly valued. The direct costs of running the trial were not considered very important, as opposed to indirect costs. From the knowledge of the prerequisites and determinants of the selection of a center for a multi-center clinical trial sponsored by pharmaceutical companies, the Empresa Brasileira de Serviços Hospitalares can promote and direct efforts to organize a network of research centers that can be very attractive.
42

Interactions between Spider Mites and Predators in Systems with Dispersal Opportunities / 分散可能な環境でのハダニと捕食者の攻防

Otsuki, Hatsune 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第22475号 / 農博第2379号 / 新制||農||1074(附属図書館) / 学位論文||R2||N5255(農学部図書室) / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 日本 典秀, 教授 田中 千尋, 准教授 刑部 正博 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
43

A Study of the Relationship Between Plains Sharp-Tailed Grouse Nest Site Selection and Survival and Ecological Site Descriptions in the Northern Plains

Klostermeier, Derek Wade January 2019 (has links)
Nest site selection and nesting success of plains sharp-tailed grouse were examined on the Grand River National Grassland in South Dakota during the nesting season from 2009-2012. We used conditional logistic regression to assess vegetation production, ecological site description, and landscape position on nest site selection. Two competing models regarding nest site selection: top model consisted of non-native forbs and native cool-season grasses, second best model included all grass and forb. Nine ESDs were used for nesting; loamy and clayey ecological sites most frequently used and produced the highest standing crop. Most frequent observed nest site State were Annual/Pioneer Perennial and Introduced and Invaded Grass. Top model for nest daily survival rates included litter, second-best model included ESD; second-best model showed negative effect for nests initiated in thin claypan, limy backslope, and sandy ecological sites. Based on daily survival estimate and 23-day incubation period, nests were 59% successful.
44

Intégration du critère de dioxyde de carbone dans la localisation des industries : le cas du cluster industriel du Havre / Integration of carbon dioxide factor in industrial location : the case of Le Havre industrial cluster

Musset, Yann 02 October 2014 (has links)
Les problèmes environnementaux, notamment ceux qui, liés au réchauffement global, ont attiré de plus en plus l’attention des décideurs de l'entreprise. Leurs préoccupations sur ces problèmes les conduisent à une réflexion de réorganisation de leurs activités. Pour les entreprises industrielles qui doivent faire face au problème des émissions de CO2, le soutien de gouvernement local qui concerne la gestion des émissions de CO2 devient non négligeable. Dans cette thèse, nous interviewons 50 décideurs de l'industrie, le gouvernement et la communauté universitaire. L’importance du problème des émissions de CO2 dans le choix de site est globalement évaluée. Nos observations suggèrent que le problème du CO2 est un facteur mineur dans la localisation des sites. Il peut être intégré dans le coût global. Pour les autorités locales, il n'est pas nécessaire d'investir dans les infrastructures de traitement des émissions de CO2 à l'heure actuelle. Nos résultats fournissent ainsi une meilleure compréhension du problème des émissions de CO2 pour les décideurs des industries locales. / Environmental problems, especially those related to the global warming have attracted extensive attention from the decision makers of companies. Their concerns on the environmental problems lead them to a reform of the mode of management. For the decision makers from industry who have to face the CO2 problem, whether they can be supported by the local government with respect to managing CO2 emissions becomes non trivial. In this thesis, we interviewed 50 decision makers from industries, government, and academic community. The significance of the CO2 problem in site selection is comprehensively evaluated. Our observations suggest that the CO2 problem is a minor factor. It can be measured by the cost. For the local government, there is no need to invest in the infrastructures of CO2 treatment at present. Our results thus provide a better understanding of the CO2 problem for the decision makers of local industries.
45

BREEDING PRODUCTIVITY, NEST DISTRIBUTION, AND POPULATION ECOLOGY OF WOOD DUCKS IN FLOODPLAIN AND UPLAND FORESTS OF SOUTHERN ILLINOIS

Anderson, Robert Gray 01 May 2010 (has links)
Wood ducks are thought to depend on mature hardwood forests juxtaposed with palustrine wetlands but these habitats have been continuously degraded or destroyed since European settlement. Wood ducks are adaptable and the use of marginal habitats and nest boxes has extended their range and probably was important to the recovery of wood duck populations. Until now no study has analyzed the contribution of upland nesting to local population growth and maintenance. I investigated predation effects on nest site selection using wood duck nests and simulated nests placed in natural cavities. Using demographic data collected on wood ducks in southern Illinois, I created a population model to compare growth rates of population segments that nested in upland and floodplain habitats. During 1993-1998, 179 of 244 radiomarked hens remained on the study area as resident hens. One hundred-four nests were located by following radiomarked hens and 66% of nests were found in upland forests. Nests in the floodplain were initiated earlier than nests in the upland. Thirty-six percent of known nest cavities were used in subsequent years but <10% were used by the same hen. Nest success was greater in upland habitats (0.78 ± 0.10) than in floodplain habitats (0.54 ± 0.18). Hen survival through the nesting season was 0.80 ± 0.03 and did not differ between habitats or age classes. Sixty-five percent (n = 43) of simulated floodplain nests were destroyed compared to 33% (n = 45) in the upland. Logistic regression models of simulated nest data indicated cavity security could be important in the fragmented floodplain forests of Union County Conservation Area (UCCA). No physical characteristics of wood duck nest cavities differentiated successful and unsuccessful nesting attempts. The growth rate of the local population was positive and estimated to be about 3%. Lambda was most sensitive to upland nesting parameters and floodplain parameters appeared to have little impact on lambda. Hens nesting in the area appear to have adapted to predation pressure by nesting in more secure floodplain cavities at UCCA or by nesting in the upland habitats. Floodplain and upland habitats are ecologically intertwined and the local wood duck population would not survive if either habitat were destroyed or severely degraded.
46

OVERT AND LATENT PATHWAYS OF POLARITY SPECIFICATION IN ZYGOTES: THE HAPLOID-TO-DIPLOID TRANSITION

Rinonos, Serendipity Zapanta 08 March 2013 (has links)
No description available.
47

Benefits, Feasibility, and Design Recommendations for a Proposed Constructed Wetland, Athens, Ohio

Lux, Emily January 2004 (has links)
No description available.
48

Reproductive consequences of nesting site decisions in a marine toadfish (Porichthys notatus)

Brown, Nicholas January 2019 (has links)
Full thesis document accompanied by all data files and R scripts to reproduce analyses in both data chapters (2 & 3). / Animals should favour breeding locations that maximize their lifetime reproductive output. Parents ought to rear young in sites that positively affect offspring but sometimes these same sites inflict costs on parents. How parents balance their own needs against those of their offspring when selecting a site for reproduction remains unclear, particularly in animals that provide extended parental care at one location. Further, few studies have linked variation in life history traits to reproductive site choices within a single species. In this thesis, I addressed both knowledge gaps by studying the plainfin midshipman (Porichthys notatus), a marine toadfish where fathers provide sole parental care to broods of young in intertidal and shallow subtidal nests for up to two months. In Chapter 2, I measured the costs incurred by caring males and the benefits conferred to offspring in nest sites along a tidal gradient. Males suffered similar rates of body condition deterioration in all nests across the intertidal gradient. Young developed more quickly in intertidal nests compared to subtidal nests, but broods in the highest intertidal nests suffered the highest mortality rates, despite receiving more parental care from the males at these nest sites. We found the most competitive males in lower intertidal nests, a trend that agrees with life history theory—in species with relatively slow offspring development, parents should accrue greater reproductive benefits from nest sites where offspring benefits are highest. In Chapter 3, I describe a laboratory experiment designed to examine how warm water and air exposure (two abiotic conditions that vary dramatically within the intertidal) affect development and survival of plainfin midshipman young, and how these effects vary with maternal traits. Exposure to warm water enhanced embryonic and larval development rates; this effect was attenuated by air exposure. Juveniles raised in warm water also exhibited superior swimming performance, while air-exposed young suffered higher mortality rates. Although larger juveniles emerged from larger eggs, development rates were similar across egg sizes. Offspring survival increased with maternal body condition in cold water but decreased with maternal body condition in warm water. Juvenile body sizes increased with maternal condition in cold water without emersion, and in warm water with emersion—the two ecologically relevant rearing environments. Thus, low condition mothers might accrue greater benefits by depositing their eggs in nests at higher tidal elevations—where development is more rapid—further supporting the idea that among-individual variation in the expression of life history traits might influence nest site preferences in these fish. In sum, my research (Chapters 2 & 3) elucidates the link between life history traits and the spatial component of animal reproductive strategies. / Thesis / Master of Science (MSc)
49

Individual and Interactive Impacts of Mercury and Agriculture on Reproduction in a Freshwater Turtle, Chelydra serpentina

Thompson, Molly Marie 26 June 2017 (has links)
In aquatic turtles, females select nest sites that have a high degree of solar exposure, and exploit recently tilled agricultural fields for nesting, presumably because of increased solar exposure and/or easier nest excavation, and the importance of incubation temperature on survival and offspring phenotype. These same disturbed sites are often contaminated by pollutants and turtles can incorporate high levels of pollutants into their eggs which negatively impact hatch success. For my M.S. research, I investigated turtle nest site selection in a system dominated by agricultural and industrial land use, the impact of crop growth on the thermal and hydric dynamics of turtle nests, and I used paired field and laboratory experiments to examine the individual and interactive impacts of agricultural land use and Hg contamination on hatch success and offspring phenotype in Chelydra serpentina. Of the 150 turtle nests found during this research, 84% were located in human-disturbed soils. Nest site characteristics were similar among nests found in Hg contaminated and reference areas. Agriculture and control nests did not differ in temperature at the time of nesting, but temperatures diverged as crops grew, with temperatures in nests in agricultural fields averaging 2.5 °C lower than control nests over the course of incubation. Similarly, despite no initial difference, nest moisture levels diverged throughout incubation and moisture averaged 107 kPa lower in agricultural than control soils throughout incubation. In my field and laboratory experiments, I found that in comparison to turtles from control incubation conditions (i.e., warmer), turtles incubated under agricultural thermal regimens (i.e., colder) took longer to hatch, hatched at smaller structural body sizes, lost more mass after hatching, had lower post-hatching structural growth rates, and were more likely to be male. Additionally, thermal conditions associated with agricultural land use interacted with high levels of mercury to impact hatching success and offspring sex ratios. My thesis research provides one of the first documentations of negative interactive effects of mercury pollution and habitat quality on early vertebrate development and highlights the importance of examining the combined influence of multiple global changes on biological systems. / Master of Science
50

Spawning Site Selection and Fry Development of Invasive Lake Trout in Yellowstone Lake, Yellowstone National Park, Wyoming

Simard, Lee 01 January 2017 (has links)
Since their discovery in Yellowstone Lake in 1994, Lake Trout (Salvelinus namaycush) have been the object of an intensive gillnet suppression program due to their predation on native Yellowstone Cutthroat Trout (Oncorhynchus clarkii bouvieri). Managers are also interested in targeting early life stages to augment suppression. A benthic sled was used to sample for Lake Trout eggs at 24 locations, hypothesized to be spawning sites, that encompassed a range of depths, slopes, and substrate composition to determine the location and characteristics of spawning sites in Yellowstone Lake. Lake Trout eggs were collected at seven sites, five of which had not been previously confirmed as spawning sites. Habitat characterization at these sites indicate Lake Trout spawning in Yellowstone Lake is limited to areas with rocky substrate, but is not constrained to areas with interstitial spaces or contour breaks as is seen within the species' native range. Lake Trout fry were captured around Carrington Island, an additional spawning site in Yellowstone Lake, in 2014 and 2015. These fry were significantly larger at each developmental stage, consumed more food beginning at earlier stages, and were captured much later into the summer than fry captured at a spawning site in Lake Champlain. The lack of potential egg and fry predators in Yellowstone Lake could be driving these differences in spawning site selection and fry behavior. This information will allow managers to identify additional spawning locations for suppression and evaluate the impact their efforts might have on the Lake Trout population in Yellowstone Lake.

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