Thèses : « Trait approach »

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Gusmão, Junior João Bosco Leite. « Sediments and functional traits : applying a functional trait approach to assess marine macrobenthic function ». reponame:Repositório Institucional da UFPR, 2017. http://hdl.handle.net/1884/48888.

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Orientadores : Dr. Paulo da Cunha Lana, Dr. Britas Klemens Eriksson
Tese (doutorado) - Universidade Federal do Paraná, Setor de Ciências da Terra, Programa de Pós-Graduação em Sistemas Costeiros e Oceânicos. Defesa: Pontal do Paraná, 21/04/2017
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Resumo: Na presente tese, investiguei como a função do macrobentos marinho de sistemas sedimentares rasos é afetada pela poluição ambiental, complexidade do habitat e mudanças na composição específica das assembleias. Utilizei uma abordagem analítica baseada em traços biológicos para estimar potenciais mudanças na função do macrobentos nos processos ecossistêmicos associados aos sedimentos. Meus objetivos de pesquisa incluem avaliações do papel dos gradientes ambientais naturais ou antropogênicos na estrutura funcional do macrobentos; da aplicabilidade das abordagens baseadas em traços biológicos para analisar a qualidade ambiental do bentos; dos efeitos das mudanças na composição específica das assembleias na função do macrobentos; do efeito da complexidade do habitat na diversidade de traços funcionais; e do impacto de espécies funcionalmente relevantes no funcionamento ecossistêmico. Os resultados e conclusões mais importantes desta tese foram: 1. Baixa qualidade do ambiente bêntico causada pelo enriquecimento orgânico prejudica o estabelecimento de espécies com determinados traços funcionais, resultando em assembleias com baixa diversidade funcional. 2. Abordagens baseadas em traços biológicos são uma forma válida de avaliação os efeitos gerais da poluição orgânica no macrobentos. Tanto a análise de traços biológicos quanto os índices multivariados de diversidade funcional representam boas ferramentas analíticas para a investigação de mudanças na estrutura macrobêntica ao longo de gradientes de contaminação orgânica. 3. As mudanças na estrutura das assembleias promovidas pelo estabelecimento de espécies exóticas podem levar a grandes mudanças na diversidade funcional do macrobentos. Essas mudanças podem aumentar o potencial de bioturbação das assembleias e ter implicações para o funcionamento do ecossistema nos sistemas sedimentares. 4. O aumento da complexidade do habitat promovido pelas gramas marinhas pode promover funções relacionadas com os sedimentos devido ao estabelecimento de organismos bioturbadores que habitam camadas superficiais do sedimento. 5. As espécies funcionalmente relevantes do macrobentos podem promover o microfitobentos, seja através do aumento da bioturbação dos sedimentos ou através da estabilização dos sedimentos devido à atenuação da hidrodinâmica local. 6. As espécies funcionalmente relevantes podem promover cascatas funcionais por favorecer o estabelecimento de organismos que desempenham outras funções. Nos casos abordados nesta tese, as gramas marinhas promovem a infauna que vive próximo à superfície do sedimento e indiretamente media processos relacionados à bioturbação; a bioturbação macrobêntica influencia os produtores primários por afetar a estrutura microfitobêntica e os bancos de mexilhões promovem a produção primária por favorecer o microfitobentos. 7. Os índices de diversidade funcional são úteis como uma ferramenta exploratória para avaliar os efeitos gerais de perturbações ou gradientes ambientais na estrutura do macrobentos. Por outro lado, a análise de traços biológicos ou o enfoque em identidades funcionais representa uma melhor abordagem para avaliar os efeitos funcionais gerais do macrobentos na estrutura e nos processos ecossistêmicos.
Abstract: In this doctoral thesis, I investigate how the function of sediment living organisms is affected by environmental pollution, habitat complexity and changes in assemblage composition in shallow sedimentary systems. I used a trait-based approach to estimate potential changes in function of the macrobenthos in sediment-related ecosystem processes. My research subjects include: the role of natural and human induced gradients in shaping assemblage functional trait structure; the applicability of trait-based approaches to assess environmental status; the effects of changes in assemblage composition on macrobenthic function; the effect of complexity on functional diversity; and the impact of functionally relevant species on ecosystem functioning. The most important findings and conclusions of this thesis are: 1. Low benthic environmental quality driven by organic enrichment hinders the establishment of macrobenthic species with specific functional traits, resulting in assemblages with differentiated trait composition and decreased functional diversity. 2. Trait-based approaches are a reliable way to assess general effects of organic pollution on the macrobenthos. Both biological trait analysis and multivariate functional diversity are good analytical tools to analyze changes in macrobenthic structure across organic contamination gradients, although biomass- and abundancebased analysis can differ. 3. Changes in assemblage structure driven by establishing alien species can drive major changes in macrobenthic functional diversity. These changes can drive increased bioturbation potential, and have implications for ecosystem functioning in sedimentary systems. 4. Increased habitat complexity driven by seagrasses can promote sediment-related functions by favoring the establishment of shallow-living macrobenthic bioturbators. 5. Functionally relevant macrobenthic species can promote microphytobenthos either by increasing sediment bioturbation or by sediment stabilization via flow attenuation. 6. Functionally relevant species can promote functional cascades by favoring the establishment of organisms that perform other functions. In the cases addressed in this thesis, seagrasses promote shallow-living infauna and indirectly mediate bioturbation-related processes; macrobenthic bioturbation drives primary producers by affecting microphytobenthic structure; and mussel beds promote primary production by favoring microphytobenthos. 7. Functional diversity indices are useful as an exploratory tool to assess general effects of disturbances or gradients on macrobenthic structure. On the other hand, biological trait analysis or the focus on functional identities represents a better approach to assess the general functional effects of the macrobenthos on ecosystem structure and processes.
Samenvatting: In dit proefschrift onderzoek ik hoe de ecologische functie van bodemorganismen wordt beïnvloed door milieuvervuiling, habitatcomplexiteit en veranderingen in de soortensamenstelling binnen ondiepe sedimentaire ecosystemen. Ik heb gebruik gemaakt van een aanpak gericht op fenotypische kenmerken (een zogeheten trait-based approach) om een inschatting te maken van potentiële veranderingen in de functie van het macrobenthos binnen sedimentgerelateerde ecosysteemprocessen. Onderwerpen binnen mijn onderzoek zijn: de rol van natuurlijke en door de mens veroorzaakte gradiënten bij het vormen van de functionele structuur van ecologische gemeenschappen; de toepasbaarheid van de trait-based approach om de toestand van het milieu te beoordelen; de effecten van veranderingen in de soortensamenstelling op de functie van het macrobenthos; de effecten van complexiteit op functionele diversiteit; en de invloed van functioneel relevante soorten op het functioneren van ecosystemen. De belangrijkste bevindingen en conclusies van dit proefschrift zijn: 1. Lage kwaliteit van de benthische omgeving, gedreven door organische verrijking, verhindert de vestiging van macrobenthische soorten met specifieke functionele kenmerken. Dit resulteert in samenstellingen met verschillende eigenschappen en verminderde functionele diversiteit. 2. De trait-based approach is een betrouwbare manier om de algemene effecten van organische vervuiling op het macrobenthos te beoordelen. Zowel een analyse van biologische kenmerken als multivariate indices van functionele diversiteit zijn nuttige analytische methoden om de veranderingen in macrobenthische structuur in verschillende gradiënten van organische vervuiling te analyseren, ondanks dat biomassa- en abundantie-analyse kunnen verschillen. 3. Veranderingen in de structuur van de soortensamenstelling gedreven door de vestiging van uitheemse soorten, kan grote veranderingen in de macrobenthische functionele diversiteit veroorzaken. Deze veranderingen kunnen een verhoogd bioturbatiepotentieel veroorzaken en hebben implicaties voor het functioneren van bodemecosystemen. 4. Toegenomen habitatcomplexiteit gedreven door zeegrassen kan sedimentgerelateerde functies bevorderen door de vestiging van ondiep levende macrobenthische bioturbators. 5. Functioneel relevante macrobenthische soorten kunnen het microfytobenthos begunstigen door bioturbatie van het sediment te verhogen of door het sediment te stabiliseren middels het verzwakken van de stroming. 6. Functioneel relevante soorten kunnen functionele cascades bevorderen door de vestiging van organismen die andere functies uitvoeren te begunstigen zoals in de gevallen besproken in dit proefschrift: zeegrassen bevorderen ondiep levende infauna en bemiddelen indirect bioturbatiegerelateerde processen; macrobenthische bioturbatie drijft primaire producenten door de microfytobenthische structuur te beïnvloeden; en mosselbedden bevorderen primaire productie door microfytobenthos te begunstigen. 7. Indicatoren van functionele diversiteit zijn nuttig als verkennend hulpmiddel om de algemene effecten van verstoringen of gradiënten op de macrobenthische structuur te beoordelen. Anderzijds vertegenwoordigen de analyse van biologische kenmerken of de focus op functionele identiteit een betere aanpak om algemene functionele effecten van het macrobenthos op de processen en de structuur van het ecosysteem te beoordelen.

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Dickinson, Maria Grace. « Climate change impacts on species : a trait-based approach ». Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/39389.

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Cleveland, Rena R. « A qualitative approach to the study of resilience in our elders ». Online version, 2003. http://www.uwstout.edu/lib/thesis/2003/2003clevelandr.pdf.

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Powney, Gary. « Understanding drivers of species distribution change : a trait-based approach ». Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/39367.

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The impacts of anthropogenic environmental change on biodiversity are well documented, with threats such as habitat loss and climate change identified as causes of change in species distributions. The high degree of variation in responses of species to environmental change can be partly explained through comparative analyses of species traits. I carried out a phylogenetically informed trait-based analysis of plant range change in Britain, discovering that traits associated with competitive ability and habitat specialism both explained variation in range changes. Competitive, habitat generalists out-perform ed species specialised to nutrient-poor conditions; a result which can be attributed to the impact of agricultural intensification in Britain. A limitation of the comparative approach is that the models do not directly test the impact of environmental change on species distribution patterns, but instead infer potential impacts. I tested the potential of comparative analyses from a spatial context by conducting a spatial analysis of plant distribution change in Britain, examining the direct impact of environmental change on the spatial distribution of the trait characteristics of species that have gone locally extinct. I discovered a loss of species associated with nitrogen poor soils in regions that had an increase in arable land cover, a result that supports the results from the trait-based analysis of plant range change and demonstrates that comparative studies can accurately infer drivers of distribution change. I found that the cross-region transferability of trait-based models of range change to be related to land cover similarity, highlighting that the trait-based approach is dependent on a regional context. Additionally, I discovered that traits derived from distribution data were significant predictors of range shift across many taxonomic groups, out-performing traditional life history traits. This thesis highlights the potential of the data accumulated through the increased public participation in biological recording to address previously unanswerable ecological research questions.

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White, Hannah Jayne. « A trait-based approach to changes in spatiotemporal patterns of biodiversity ». Thesis, Queen's University Belfast, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728827.

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Spatial and temporal variation in biodiversity is shaped by a combination of abiotic and biotic factors. Most research into these relationships has focused on taxonomic diversity as the currency of biodiversity; however, this term covers a range of other aspects including genetic diversity, phylogenetic diversity and, the focus of this thesis, functional diversity. The range and variation in species traits is a vital area of research due to their importance in ecosystem functioning as well as determining species responses to the environment. They are, therefore, a crucial biodiversity component to consider in conservation science. The main aim of this thesis was to identify spatial and temporal patterns of functional diversity and to determine how these differ from observed patterns of taxonomic diversity such as species richness using a range of statistical approaches to deal with the inherent characteristics of biodiversity data such as spatial autocorrelation. Primarily this thesis focuses on British birds, but Scottish machair vegetation is also considered. These represent well recorded datasets so that statistical relationships revealed are a true representation of biological phenomena as opposed to a map of recorder effort. Spatial drivers of functional diversity differ from those of taxonomic diversity indicating a decoupling of the two biodiversity axes. Additionally, patterns of functional homogenisation do not match with those of taxonomic homogenisation. Despite differences in spatial patterns of species and traits, interspecific variation in the drivers of changes in species occurrences can partially be explained by their traits indicating a link between the two. Phylogenetic diversity also varies spatially and the location of biodiversity hotspots shifts not only with the diversity metric being investigated but also the spatial scale of measurement. This thesis highlights a number of important considerations for conservation planning and the results can contribute to better predictions, and understanding, of the consequences of climate change.

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Hellgren, Alfred, et Henrik Hörnberg. « Från elitidrott till yrkeskarriär : En studie av elitidrottsutövares upplevelser av karriärövergång och ledarkvalitéer ». Thesis, Umeå universitet, Pedagogiska institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-138701.

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There have been numerous of examples where former elite athletes have had a problem with adaptingto the life as a civilian. Research has shown that it is common among former athletes to experiencenegative emotions when ending an elite career in sports. What separated the ones who successfullymoved on to achieve greatness outside of the sports environment? This study was about female formerelite athletes which have a senior position and their views on what role the elite career had on theirfollowing career. The purpose of the study was to examine what generic traits, knowledges and skillsthat elite sports can help to develop and that is usable in a senior position. The study also aimed togain knowledge about how female former elite athletes from the county of Vasterbotten, Sweden,experienced and handled the transition from elite sports to the life as a civilian. To answer thesequestions eight interviews were conducted with female former elite athletes from a variety of sports.The main result showed that there were several factors that helped these former elite athletes tohandle the transitional phase in a good way. They all agreed that elite sports helped to develop goaldetermination, a will to continually evolve, manage both success and adversity and lastly teamworkand social skills. Regarding how their athletic career influenced the job opportunities following theircareer termination, the study found that their athletic career had either a direct or indirect influence.

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Roquer, Beni Laura. « Pollinator communities and pollination services in apple orchards : a trait-based approach ». Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/670800.

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La biodiversitat està amenaçada arreu del món a conseqüència d’activitats humanes com el canvi d’usos del sòl, l’explotació de recursos o el canvi climàtic. Durant els darrers 20 anys, les aproximacions basades en trets s’han anat incorporant de manera creixent en estudis que relacionen la biodiversitat, l’estructura de les comunitats i el funcionament ecosistèmic, com a alternativa a les aproximacions taxonòmiques. La pol·linització és un servei ecosistèmic cabdal que contribueix a la reproducció sexual de més del 85% de les espècies d’angiospermes al món. A més, els pol·linitzadors proveeixen d’un servei ecosistèmic cabdal a través de la seva contribució a la producció agrícola i a la nutrició humana. Tanmateix, la diversitat de pol·linitzadors està experimentant forts declivis a Europa. La intensificació agrícola és una de les principals causes d’aquests declivis. Els trets funcionals determinen les respostes dels pol·linitzadors (individus o espècies) a les alteracions ambientals (trets resposta) i, al mateix temps, contribueixen al funcionament ecosistèmic (trets efecte). Les aproximacions basades en trets ja fa temps que s’utilitzen en plantes i, en canvi, no tant en animals vertebrats. Per molts grups d’invertebrats terrestres encara falta consens sobre quins trets cal mesurar, com, i quin poder predictiu tenen. Diversos estudis han analitzat els efectes de la intensificació agrícola sobre la composició funcional, i d’altres han analitzat el rol de la composició funcional sobre el servei de la pol·linització. Tot i això, són pocs els estudis que utilitzen un marc de trets resposta-efecte. L’objectiu d’aquesta tesi és entendre millor els mecanismes que relacionen la composició funcional amb la provisió del servei de la pol·linització en camps de pomera. Per fer-ho, vaig mesurar diferents trets de pol·linitzadors en 109 espècies de per tal d’estudiar el rol funcional individual i a nivell d’espècie. També vaig utilitzar aquests trets per estudiar com la composició funcional de pol·linitzadors responia a factors agrícoles a escala local i de paisatge i com, a la vegada, aquests trets afectaven al servei de la pol·linització a nivell de comunitat. Primer, vaig desenvolupar un mètode estandarditzat per mesurar quantitativament la pilositat, un tret important en l’ecologia de la pol·linització. El mètode proposat considera dos components de la pilositat (la llargada i la densitat dels pèls) i es va utilitzar en 109 espècies pertanyents a diferents grups de pol·linitzadors. Segon, vaig determinar quins trets dels pol·linitzadors promovien l’eficàcia pol·linitzadora i vaig explorar si pol·linitzadors amb eficàcies pol·linitzadores similars compartien també trets similars. Vaig observar que l’eficàcia pol·linitzadora no depenia d’un únic tret sinó de diversos trets morfològics i de comportament. Els trets que tenien més efecte sobre l’eficàcia pol·linitzadora van ser el comportament intrafloral, la mida corporal i la durada de les visites. Tots els pol·linitzadors eficients s’aproximaven a les flors des de dalt però, a banda d’això, no compartien necessàriament altres trets. Finalment, vaig analitzar com factors locals i de paisatge afectaven al servei de la pol·linització mitjançant canvis en la composició funcional en 110 camps de pomes de diferents zones d’Europa. El servei de la pol·linització va incrementar amb la diversitat funcional de pol·linitzadors, però només en camps de gestió poc intensiva. Així, camps poc intensius amb una alta diversitat funcional van assolir nivells de serveis de pol·linització similars als dels camps de gestió intensiva.
La biodiversidad está siendo amenazada en todo el mundo a consecuencia de actividades humanas como el cambio de los usos del suelo, la explotación de recursos o el cambio climático. Durante los últimos 20 años, las aproximaciones basadas en rasgos se han ido incorporando de manera creciente en los estudios que relacionan la biodiversidad, la estructura de las comunidades y el funcionamiento ecosistémico, como alternativa a las aproximaciones taxonómicas. La polinización es un servicio ecosistémico clave que contribuye a la reproducción sexual de más del 85% de las especies de angiospermas del mundo. Además, los polinizadores proveen un servicio ecosistémico clave a través de su contribución a la producción agrícola y a la nutrición humana. Asimismo, la diversidad de polinizadores está experimentando fuertes declives en Europa. La intensificación agrícola es una de las principales causas de estos declives. Los rasgos funcionales determinan las respuestas de los polinizadores (individuos o especies) a las alteraciones ambientales (rasgos respuesta) y, al mismo tiempo, contribuyen al funcionamiento ecosistémico (rasgos respuesta). Las aproximaciones basadas en rasgos ya hace tiempo que se utilizan en plantas y, en cambio, no son tan utilizadas en animales vertebrados. En muchos grupos de invertebrados terrestres aún falta consenso sobre qué rasgos es necesario medir, cómo, y qué poder predictivo tienen. Diversos estudios han analizado los efectos de la intensificación agrícola sobre la composición funcional y otros han analizado el rol de la composición funcional sobre el servicio de la polinización. En cambio, son pocos los estudios que utilizan un marco de rasgos respuesta-efecto. El objetivo de la presente tesis es entender mejor los mecanismos que relacionan la composición funcional con la provisión del servicio ecosistémico de la polinización en campos de manzana. Para ello, medí 10 rasgos de polinizadores en 109 especies de grupos diferentes para estudiar el rol funcional individual y a nivel de especie. También utilicé los rasgos para estudiar cómo la composición funcional de polinizadores respondía a factores agrícolas tanto a escala local como de paisaje y de cómo, a la vez, estos rasgos afectan al servicio de la polinización a nivel de comunidad. Primero, desarrollé un método estandarizado para medir cuantitativamente la pilosidad, un rasgo importante en ecología de la polinización. El método propuesto tiene en cuenta dos componentes de la pilosidad (la longitud y la densidad de los pelos) y se utilizó en 109 especies pertenecientes a diferentes grupos de polinizadores. Esperamos que este método incentive la inclusión de la pilosidad en bases de datos de polinizadores y contribuya al conocimiento sobre la importancia de este rasgo en la ecología de la polinización. Segundo, determiné qué rasgos de los polinizadores promueven la eficacia polinizadora y exploré si polinizadores con eficacias similares compartían también rasgos similares. Observé que la eficacia polinizadora no depende de un único rasgo sino de varios rasgos morfológicos y de comportamiento. Los rasgos que afectaron más a la eficacia polinizadora fueron el comportamiento intrafloral, el tamaño corporal y la duración de las visitas. Todos los polinizadores eficientes se aproximaban a las flores desde arriba, pero no compartían necesariamente otros rasgos. Finalmente, analicé cómo factores locales y de paisaje afectan al servicio de la polinización mediante cambios en la composición funcional en 110 campos de manzana de diferentes zonas de Europa. El servicio de la polinización incrementó con la diversidad funcional de polinizadores, pero solo en campos de gestión poco intensiva. Así, campos poco intensivos con una diversidad funcional alta obtuvieron niveles de polinización similares a los campos de gestión intensiva. La relación entre los rasgos respuesta y efecto se vio más influenciada por la diversidad funcional que no por rasgos funcionales concretos.
Biodiversity is being threatened worldwide as a result of human activities such as land use change, exploitation of resources or climate change. During the last 20 years, trait-based approaches have been increasingly incorporated in studies linking biodiversity, community structure and ecosystem functioning, as an alternative to taxonomy-based approaches. One crucial ecosystem function is pollination, which contributes to the sexual reproduction of more than 85% of angiosperm species worldwide. In addition, pollinators provide a crucial ecosystem service through their contribution to agricultural production and human nutrition. However, pollinator diversity is experiencing strong declines in Europe and North America. Agricultural intensification is considered one of the main drivers of these declines. Functional traits mediate the responses of pollinators (individuals or species) to environmental disturbances (response traits) and, at the same time, contribute to ecosystem function (effect traits). Trait-based approaches have long been used in plant studies and, to a lesser extent, studies on vertebrate animals. However, for many groups of terrestrial invertebrates there is still a lack of consensus on which traits should be measured, their predictive value and how they should be measured. Several studies have addressed the effects of agricultural intensification on pollinator functional composition and others have addressed the role of functional composition on pollination service. However, of studies analysing both processes simultaneously using a response-trait effect framework remain very scarce. The aim of this thesis is to better understand the mechanisms linking functional composition with pollination service provision in apple orchards. To do so, I measured 10 pollinator traits in 109 species of different pollinator groups to study pollinator functional performance at individual and species level. I also used these traits to study how pollinator functional composition responded to agricultural local and landscape features and how, in turn, these traits affected pollination service at the community level. First, I developed a standardized method to quantitatively measure hairiness, a salient trait in pollination ecology. The proposed methodology accounts for the two components of hairiness (hair length and hair density) and was used on 109 species from different pollinator groups. Hopefully the method will foster the inclusion of hairiness in pollinator data bases and contribute to our understanding of the relevance of this trait in pollination ecology. Second, I determined which pollinator traits promote pollination effectiveness and explored whether pollinators with similar pollination effectiveness share similar traits. I found that pollination effectiveness was not dependent on a single trait but on a variety of behavioural and morphological traits. The main traits affecting pollination effectiveness were flower handling behaviour, body size and visit duration. All effective pollinators were top-workers, but otherwise did not necessarily share similar traits. Third, using a response-trait framework, I analysed how local and landscape features affected pollination service through changes in functional composition in 110 apple orchards across Europe. Pollination service increased with pollinator functional diversity, but only in low-input orchards. As a result, low-input orchards with high pollinator functional diversity reached levels of pollination service similar to those of high-input orchards. The relationship between response and effect traits was better mediated by functional diversity rather than specific functional traits. Functional diversity enabled pollinator communities to better respond to management and landscape intensity and to increase pollination function through complementarity.

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Nodarse, Brynn C. « A nonverbal approach to charismatic leadership training ». Diss., UC access only, 2009. http://proquest.umi.com/pqdweb?index=8&did=1907259901&SrchMode=2&sid=3&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1270057484&clientId=48051.

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Thesis (Ph. D.)--University of California, Riverside, 2009.
Includes abstract. Includes bibliographical references (leaves 111-115). Issued in print and online. Available via ProQuest Digital Dissertations.

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Hodge, Josh. « Using the plant trait-based approach to study temperate grassland ecology and restoration ». Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/110962/.

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Grasslands are considered to be the most endangered terrestrial ecosystem in the world. In the United Kingdom, substantial losses in unimproved grasslands and the abandonment of traditional grazing has resulted in the decline of ecosystem services, such as pollination. A plant trait-based approach was conducted to study the community ecology and restoration of temperate grasslands, with a focus on the convergence/divergence patterns in response to environmental and management factors, and how these scale to the provision of ecosystem processes and services –biomass production and livestock. The role of seven plant traits, obtained from the TRY-database, was investigated using the botanical data of the National Vegetation Classification, the Park Grass Experiment and the North Wyke Farm Platform. Trait-based analyses were conducted on the latter two to investigate the provision of biomass production and livestock production. A microcosm experiment was conducted to test the effects of agricultural soil legacies and restoration seed mixture on the reassembly of grassland communities, and their associated functional structure and composition. It was found that the seven traits investigated were independent and countered the conceptualisation of ecological axes of specialisation and ecological strategies. The type of fertiliser used to improve grasslands was found to be a significant factor driving the convergence/divergence patterns of temperate grassland communities, together with grazing. Biomass production was found to be best explained by statistical models incorporating climate and environmental factors, community-weighted means and different facets of functional diversity. In essence, environmental and management pressures resembling intensely managed, especially with nitrate-based fertilisers, temperate grasslands and an exploitative community best supported greater amounts of high quality biomass. Livestock production was found to be best explained by the Functional Diversity Hypothesis: higher yields from cattle and sheep were found from diverged grazing pastures. A trade-off between cattle quantity and quality was also highlighted. Agricultural soil legacies were found to greatly hinder the progression towards vegetation and functional restoration targets, producing ruderal communities dominated by weak competitors and opportunistic weedy plant species. The work has important implication for the management and restoration of grassland communities.

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Véron, Laélia. « Le trait d’esprit dans "La Comédie humaine" de Balzac : étude stylistique ». Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEN003.

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L’esprit, comme forme de la conversation, est au XIXe siècle une notion fondamentalement ambiguë. Hérité du XVIIe siècle et de l’âge d’or de la conversation, profondément marqué par les bouleversements de l’âge post-révolutionnaire, bousculé par le développement de la mystification, du persiflage, de la blague, et de la raillerie journalistique, le trait d’esprit prend tendanciellement un tour agonistique et instrumental dans les luttes sociales de l’époque. Balzac, journaliste, blagueur, mais aussi conservateur et amoureux des « conversation[s] entre onze heures et minuit » paraît emblématique de cette ambiguïté. Le trait d’esprit, parole brillante et concise, qui se veut singulière, peut être appréhendé comme un énoncé détachable. Notre approche stylistique sera donc en premier lieu celle d’une analyse des figures, au niveau de l’unité-énoncé et des catégories syntactico-sémantico-lexicales de la phrase. Cependant, suite aux acquis de la grammaire du texte, il apparaît que la signification même de ces catégories ne peut être comprise que par rapport à des structures extra-énoncives : nous tenterons ainsi de replacer systématiquement ces énoncés dans leur contexte discursif. Considérant que le trait d’esprit, en tant que performance sociale, doit être défini en partie par les conditions mêmes de son énonciation, nous tenterons de comprendre le fonctionnement de cet acte socio-discursif grâce aux acquis de l’analyse du discours. Notre travail privilégiera donc une approche conversationnelle (ou interactionnelle, selon les terminologies) et pragmatique, en s’attachant à étudier non seulement ce que dit le trait d’esprit, mais aussi ce qu’il communique, qu’il s’agisse des traits d’esprit des personnages ou de ceux du narrateur. L’interaction dialectique de ces deux niveaux nous permettra d’interroger la valeur romanesque du trait d’esprit, parole ambiguë, entre référence sérieuse et jeu métalinguistique, caractéristique du réalisme paradoxal de La Comédie humaine
The notion of “esprit” (French wit), a feature of the art of conversation, was, all through the 19th century, an ambiguous one. The art of witticism – a legacy of the 17th century and of the golden age of conversation – was, however, deeply altered by the advent of other forms of wit such as mystification, persiflage, jokes and journalistic banter : “traits d’esprit” (witticisms) gradually took on an agonistic dimension and became instruments in the social struggles of the time. Balzac, a journalist, a joker but also a conservative writer and a lover of “conversations between eleven o'clock and midnight” is emblematic of this ambiguity. “Traits d’esprit” (Witticisms) – short and clever statements aimed at being remarkable – can be studied as stand-alone utterances. That is why I shall first proceed to an analysis of the stylistic devices at work at the level of utterance, and relying on syntactic, semantic and lexical categories. However, drawing from the findings of text grammar, it appears that the meaning of these categories can only be understood in relation to an extra-utterance context and structures. Therefore, I shall systemically attempt to contextualize these utterances within a larger discursive framework. “Traits d’esprit” being social performances, they have to be defined in regard to the situation of utterance. I shall therefore use the tools of discourse analysis in order to break down the mechanisms of such a socio-discursive act. The present work thus relies on a conversational (or interactional) and pragmatic approach. It attempts to tackle not only what is said but also what is conveyed in those “traits d’esprit”, whether they belong to the characters’ or the narrator’s discourse. It is through the dialectic interaction between these two levels of wit that I intend to assess the role of witticisms. Ambiguous utterances, “traits d’esprit” pertain to serious references as well as to metalinguistic games, and are thus characteristics of the paradoxical realism to be found in La Comédie humaine

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Juárez, Escario Alejandro. « A trait-based approach to disentangle the success of alien weeds in irrigated crops ». Doctoral thesis, Universitat de Lleida, 2016. http://hdl.handle.net/10803/399590.

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El estudio se centra detectar los cambios temporales sufridos en la composición florística de las comunidades de malas hierbas de los cultivos de regadío y en descifrar los factores intrínsecos y extrínsecos subyacentes al éxito de las especies exóticas en estos cultivos y a su capacidad de colonizar los hábitats naturales adyacentes. Se ha utilizado una aproximación funcional. Los resultados muestran que a largo plazo, ha habido cambios en la diversidad, la composición y la estructura funcional de las comunidades de malas hierbas y un incremento del protagonismo de las malas hierbas exóticas. En los cultivos frutales, entre los atributos funcionales más beneficiados destacan la vía fotosintética C4, las formas graminoides y perennes y la capacidad de reproducción vegetativa, así como la hidrocoria y las semillas adaptadas a más de un modo de dispersión. Estos atributos se encuentran representados principalmente en las especies exóticas y su selección está determinada fundamentalmente por el sistema de riego por inundación. Por otro lado, el manejo de los cultivos regados por goteo configura una comunidad de malas hierbas caracterizada por una menor prominencia de especies exóticas y una estructura funcional que la hace menos competitiva hacia los árboles frutales. Los atributos favorecidos en los cultivos frutales regados por inundación se relacionan con la capacidad de las malas hierbas exóticas para colonizar los ambientes riparios adyacentes a los cultivos.
L'estudi es centra a detectar els canvis temporals de la composició florística de les comunitats de males herbes dels cultius de regadiu i a desxifrar els factors intrínsecs i extrínsecs subjacents a l’èxit de les espècies exòtiques en aquests cultius i a la seva potencial capacitat de colonitzar els hàbitats naturals dels voltants. S’ha utilitzat una aproximació funcional. Els resultats mostren que a llarg termini, ha hagut canvis en la diversitat, la composició i l’estructura funcional de les comunitats de males herbes a més d’un increment del protagonisme de les males herbes exòtiques. Als fruiters, entre els atributs funcionals més beneficiats destaquen la via fotosintètica C4, les formes graminoides i perennes i la capacitat de reproducció vegetativa, així com la hidrocòria i les llavors adaptades a més d’un mode de dispersió. Aquests atributs es troben representats principalment a les espècies exòtiques i la seva selecció està dirigida fonamentalment pel sistema de regadiu per inundació. Per altra banda, el maneig dels cultius regats per degoteig configura una comunitat de males herbes caracteritzada per una menor prominència d’espècies exòtiques i una estructura funcional que la fa menys competitiva envers els arbres fruiters. Els atributs que es veuen afavorits en els fruiterars irrigats per inundació també es troba relacionat amb la capacitat que tenen les males herbes exòtiques per colonitzar els ambients riparis adjacents als cultius.
This study aims at identifying temporal changes in weed community composition as well as unravelling the intrinsic and extrinsic factors that lay behind the success of alien weeds in irrigated crops and their potential capability to spread and colonize surrounding natural habitats. These main goals were addressed using a trait-based approach. Results showed that at long-term temporal scale, there were changes in diversity, composition and functional structure of weed communities, accompanied by a higher prominence of alien plants within these weed assemblages. In orchards, C4 photosynthesis, graminoid and perennial forms, clonal reproduction, hydrochory and seed dispersed by multiple methods were among the most benefited plant traits, which were mainly found in successful alien weeds. This trait selection was mainly driven by flood irrigation. On the other hand, management in drip-irrigated orchards configures a weed community characterized by a lower prominence of alien species and a functional structure that make it less competitive to the trees.Furthermore, the trait syndrome favoured in flood-irrigated orchards was also linked to the capacity of alien species to overcome ecosystems filtering and colonize surrounding natural riparian habitats.

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Lasky, Benjamin M. « Chronic accessibility of virtue-trait inferences : a social-cognitive approach to the moral personality ». Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1177985.

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This study examined the hypothesis that the moral personality is one in which moral knowledge structures are chronically accessible. A spontaneous trait inference cued-recall paradigm was employed. It was expected that those with chronically accessible moral knowledge structures (N = 61) would spontaneously encode virtue-content information differently than those with less chronically accessible moral knowledge structures (N = 77). High and low moral chronic accessibility participants were instructed to memorize sentences that contained virtue-content implications. Sentence recall was then cued by either virtuous dispositional terms or by words that were linked semantically to the sentences. Within the spontaneous processing condition, dispositional cues prompted twice as much recall as semantic cues among participants with high moral chronic accessibility whereas semantic cues prompted twice as much recall as dispositional cues among participants with low moral chronic accessibility. As predicted, within the deliberate processing conditions, there were no high/low moral chronic accessibility differences. These findings support the claim that the moral personality is usefully conceptualized in terms of the chronic accessibility of moral knowledge structures.
Department of Educational Psychology

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Vitacco, Michael J. « Construct Validity of Psychopathy in Mentally Disordered Offenders : A Multi-trait Multi-method Approach ». Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc4168/.

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Psychopathy continues to receive increased attention due to the negative outcomes, including recidivism, violence, and poor treatment amenability. Despite the vast amount of attention psychopathy has received, research on its applications to mentally disordered offenders remains sparse. The current study explored the relationship between psychopathy, depression, anxiety, and psychotic disorders. It also investigated the comparative fits of two and three-factor models of the PCL-R with mentally disordered offenders. Participants consisted of 96 inmates placed in the mental health pod at Tarrant County Jail. A Confirmatory Factor Analysis (CFA) with testlets found the three-factor PCL-R model had excellent fit (Robust Comparative Fit Index = 1.00). Psychopathy was found to be a construct independent of mental disorders. Two exceptions were (a) a modest correlation between anxiety and Impulsive and the Irresponsible Lifestyle factor of the PCL-R (r = 0.20) and (b) a modest negative correlation between Deficient Affective Experience of the PCL-R and mania (r = -.37). Based on the current data, treatment programs for mentally disordered offenders are suggested that focus on both behavioral and personality aspects of psychopathy.

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Plumb, Sarah. « A positive clinical psychology approach to developing resilience among state employed nurses ». Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/d1018879.

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Nurses are confronted with numerous work-related stressors that can result in burnout. This can contribute to absenteeism and high turn-over rates in the nursing profession. A review of the literature indicated that psycho-educational interventions to increase resilience could be an effective way of addressing this problem. The study aimed to develop a positive clinical-psychology approach to increasing resilience in State employed nurses. The study used a mixed-method approach to determine the current psychological functioning of a sample of 87 nurses. Quantitative data on personality traits, character strengths and levels of resilience were obtained, using the NEO PI-R, VIA – IS, and Resilience Scale. Qualitative data on the coping responses of nurses were obtained through the thematic analysis of focus groups. These data were integrated to create a positive clinical psychology conceptualisation of resilience and to develop therapeutic guidelines for a group psycho-educational intervention. The results of the study indicated a struggling psychological profile. This was defined as the ability to deal with work-related stressors – but with the potential risk of developing symptoms of burnout. The moderate levels of resilience were attributed to elevated character strengths in the sample. The distribution of personality traits indicated that the nurses in the sample were at risk of developing burnout; and this prevented them from flourishing. These data were synthesised to create therapeutic guidelines for developing resilience aimed: (1) increasing emotional stability and invulnerability; (2) increasing agreeableness; and (3) increasing conscientiousness. These guidelines were based on the personality traits that were deemed to negatively impact the resilience of the nurses. These personality traits were correlated with several character strengths that displayed strong relationships with resilience. This indicated that resilience could be developed through the cultivation of the following character strengths: perspective; perseverance; fairness; forgiveness; leadership; love; zest; hope; curiosity; and appreciation of beauty and excellence. These character strengths were identified to facilitate the positive adaptation of the personality traits identified in the therapeutic guidelines. A group psycho-educational intervention was developed, using the positive clinical psychology conceptualisation of resilience. The literature was reviewed to identify techniques to cultivate the ten character strengths specified in the therapeutic guidelines. These techniques were adapted to create experiential learning processes for the intervention. This psycho-educational programme can be applied as a secondary and tertiary intervention. It can be used to increase resilience to prevent burnout among nurses. It can also be used to psychologically empower nurses that have existing symptoms of burnout.

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Subedi, Suresh Chandra. « A Functional Trait Approach to Examine Plant Community Dynamics in South Florida Hardwood Hammock Forests ». FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3373.

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The tropical hardwood forests of south Florida persist as well-drained patches of broadleaf forest separated by brackish water swamp, marsh, or pineland. In this dissertation, a functional trait approach was used to understand the structure and dynamics of these communities and their responses to abiotic and biotic variation. Twenty-seven permanent plots (20 x 20 m2) were established across the south Florida landscape, representing four sub-regions: Everglades marsh, Long Pine Key, Upper Keys, and Lower Keys. Community weighted mean trait values for four of six selected traits showed significant inter-sub-regional variation. Out of them, three traits (specific leaf area, tree height, and leaf phosphorus) increased significantly from dry and low productivity Florida Keys in the south to the moist and productive areas on the south Florida mainland, while wood density showed the opposite pattern. Trait variance ratios (T-statistic metrics) was used to explore internal filtering (processes that operate within a community) and external filtering (processes that operate at larger scale than that of the individual population or community) on community structure. Both external and internal filtering in the functional composition of south Florida hardwood hammock forest were important for local communities differing in freshwater accessibility, or that occupy different positions along strong edaphic or climatic gradients. To understand the underlying mechanisms that drive species assembly during forest succession in Florida dry sub-tropical forest, 13 leaf, stem, reproductive, and architectural traits of resident tree species across the successional gradient were measured. Tests of null models showed that younger communities are shaped by environmentally driven processes, while mature communities are shaped by competitively driven processes. The overall trait similarities among species present in North Key Largo tropical dry forest suggest that tree species are specialists on the local environment, and their ability to survive and grow in a stressful environment may be more important than competition for resources at larger scale. Moreover, tree species in these forests may exhibit specialization or trait plasticity in coping with drought by changes in their stomatal morphology or activity, allowing for a balance between gas exchange and water loss in a periodically stressful environment. A significant negative correlation between stomatal density and size, and a positive correlation between leaf δ13C and stomatal density were observed across habitat gradient for one of the dominant hardwood hammock species (Bursera simaruba). Small and densely distributed stomates in tandem seems to represent a strategy that allows hammock species to conserve water under physiological drought. Furthermore, findings from this work also showed both intra- and inter-specific trait variation at regional and local scales influence community assembly patterns in hardwood hammock communities in South Florida.

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Yang, Tun-Hsiang. « Family based liquid association study an approach to map the disease genes for the complex trait / ». Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1610653951&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Snedeker, John. « A Genetic Approach to the Role of Primary Cilia in Forebrain Development ». University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535458396250938.

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Forgetta, Vincenzo. « Systematic search for Salmonella-susceptibility quantitative trait loci in the chicken using a whole genome scan approach ». Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33758.

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The goal of this project is to identify QTL involved in Salmonella -susceptibility in the chicken. Salmonellosis is one of the most common causes of food poisoning in humans and is frequently caused by the ingestion of Salmonella-contaminated poultry products. Identification of QTL responsible for Salmonella-susceptibility may lead to more efficient control strategies, and selection against genes that may lead to increased risk of transmission. The genome scan was performed on a selection of 425 backcross progeny, (W1 x C) F1 x C, derived from C Salmonella-susceptible and W1 Salmonella-resistant chickens. The 425 backcross birds were phenotyped for their susceptibility to infection with Salmonella Typhimurium. A collection of 160 fluorolabelled microsatellite markers (FAM, TET, and HEX) was used to scan the chicken genome, which is 3800cM in size (1.2 x 109 bp) and consists of 39 linkage groups, 9 chromosomes and 30 microchromosomes. We first tested the available microsatellite markers for informativeness in C and W1 chicken lines. In addition, we also determined the allele lengths and PCR product intensity (qualitatively) to facilitate pooling of markers during electrophoresis. PCR reaction mixtures were prepared using a Packard MultiProbe II Robotic System and Minitrak to pipette DNA-PCR Master mix and primer mix into microtiter plates. PCR products were then pooled and analyzed on Perkin-Elmer ABI Prism 3700 DNA Analyzers. Analysis of informative microsatellite markers on the backcross panel resulted in the detection of two loci, one on Chromosome 7 carrying NRAMP1, and the other on microchromosome E41W17 carrying TLR4, linked to resistance to Salmonella infection in chickens.

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Bass, Julia [Verfasser], Michael [Akademischer Betreuer] Kleyer et Gerhard [Akademischer Betreuer] Zotz. « Biodiversity effects on dune and salt marsh biogeomorphology : a trait-based approach / Julia Bass ; Michael Kleyer, Gerhard Zotz ». Oldenburg : BIS der Universität Oldenburg, 2019. http://d-nb.info/1205879072/34.

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Carvalho, Gomes Da Silva Fabio. « Using plant functional traits to assess ecosystem processes and community dynamics in lowland fens : understanding the efficacy and applicability of a trait-based approach to plant ecology ». Thesis, Kingston University, 2017. http://eprints.kingston.ac.uk/38654/.

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The research presented here focuses on the functional aspect of biodiversity of plant communities, with emphasis placed on the functions of species within biological communities and ecosystems, rather than their identity. The prominence of plant functional traits as major contributors to ecosystem functioning is based on underlying mechanisms whereby individual species interact with each other and with their abiotic environment to influence ecological processes on different spatial scales. In this study, particular attention is given to the modulating effects of functional diversity and composition on community dynamics and ecosystem processes (e.g., soil processes relevant to the cycles of carbon and nitrogen), as well as its response to disturbance. A number of green leaf functional traits considered to be pertinent to soil processes and the biogeochemical cycles of carbon and nitrogen were measured from vascular plant species growing in lowland fens in East Anglia, UK. Such habitats are widely recognised as areas of high conservation value for providing numerous benefits to society, including nutrient cycling and soil carbon storage. The set of analyses presented here reveals the implications of different degrees of management intervention for the functional composition of lowland fen plant communities. Overall, the functional diversity of such communities were found to respond strongly to changing disturbance intensity, to significantly interact with abiotic factors to contribute to the provision of ecosystem processes and to exert major effects on species coexistence within plant assemblages. These results confirm the wide applicability of the trait approach when investigating the effects of biodiversity on the stability of biological communities and ecosystems, and is potentially informative to conservation focused projects that aim to simultaneously enhance biodiversity and the provision of vital ecosystem services. In fact, management intervention was largely found to favour species with a set of traits conducive to enhancing soil carbon storage, lending support to current long term conservation projects that aim to positively influence soil carbon balance.

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Garrido, Martín Diego 1992. « A Multivariate approach to study the genetic determinants of phenotypic traits ». Doctoral thesis, Universitat Pompeu Fabra, 2020. http://hdl.handle.net/10803/668497.

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We have developed an efficient and reproducible pipeline for the identification of genetic variants affecting splicing (splicing quantitative trait loci or sQTLs), based on an approach that captures the intrinsically multivariate nature of this phenomenon. We employed it to study the multi-tissue transcriptome GTEx dataset, generating a comprehensive catalogue of sQTLs in the human genome. Downstream analyses of this catalogue provide novel insights into the mechanisms underlying alternative splicing regulation and its contribution to human complex traits and diseases. To facilitate the visualization of splicing events in GTEx and other large-scale RNA-seq studies, we developed a software to generate sashimi plots, which supports the aggregated representation of hundreds of samples. Given the growing interest in efficient methods to identify genetic effects on multiple traits, we extended the statistical framework employed for sQTL mapping (Anderson test) to accommodate any quantitative multivariate phenotype and experimental design. We derived the limiting distribution of the test statistic, allowing to compute asymptotic p values. We further demonstrated the advantages and applicability of our approach to GWAS and QTL mapping analyses using simulated and real datasets.
Hemos desarrollado un método computacional eficiente y reproducible, que permite la identificación de variantes genéticas que afectan al splicing (splicing quantitative trait loci o sQTLs), y que es capaz de capturar la naturaleza multivariante de este fenómeno. Lo hemos empleado para estudiar el conjunto de datos GTEx, que contiene información sobre el transcriptoma en múltiples tejidos, generando un catálogo completo de sQTLs en el genoma humano. El análisis de dicho catálogo proporciona nuevos conocimientos sobre los mecanismos que subyacen a la regulación del splicing alternativo, así como sobre su contribución a los rasgos complejos y enfermedades humanas. Con el objetivo de facilitar la visualización de eventos de splicing en GTEx y otros estudios de secuenciación de ARN a gran escala, hemos desarrollado un software para generar gráficos de tipo sashimi, que permite la representación agregada de cientos de muestras. En vista del creciente interés por métodos capaces de analizar efectos genéticos en múltiples rasgos de manera eficiente, hemos extendido el marco estadístico empleado para la identificación de sQTLs (test de Anderson) para acomodar cualquier fenotipo multivariante cuantitativo y diseño experimental. Hemos derivado la distribución límite del estadístico, lo que nos permite calcular p valores asintóticos. Además, demostramos las ventajas y la aplicabilidad de nuestro método en GWAS y análisis de QTLs, empleando conjuntos de datos tanto simulados como reales.

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Park, Hee-Bok. « Genetic Analysis of Quantitative Traits Using Domestic Animals : A Candidate Gene and Genome Scanning Approach ». Doctoral thesis, Uppsala University, Department of Medical Biochemistry and Microbiology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4582.

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Domestication has led to genetic changes that affect quantitative traits in farm animals. Both candidate gene analysis using association tests and genome scans based on linkage analysis have been performed to understand the molecular basis underlying quantitative genetic variation in horses, pigs and chickens. To test a possible association of polymorphisms in the PRKAG3 gene, previously found to be associated with excess glycogen content in pig skeletal muscle, with quantitative traits in the horse, the major coding part of the equine PRKAG3 sequence was identified. Bioinformatic characterization of the equine PRKAG3 gene was conducted. A single nucleotide polymorphism (SNP) causing a missense mutation (Pro258Leu) was found. Screening this SNP showed that the Leu258 allele was more frequent in breeds with heavy muscularity. To assess previously reported associations between polymorphisms in the MC4R gene and obesity-related traits further, we conducted linkage analysis between the MC4R locus and fatness-related traits using a Wild BoarxLarge White intercross. No significant association between segregation at the MC4R locus and fatness was detected in this pedigree. A genome scan of quantitative trait loci (QTLs) has been performed in an intercross between chicken lines divergently selected for growth. Divergent parental lines have been established by selecting for high and low 56-day body weight for over 40 generations. The selection has led to approximately a 9-fold difference in 56-day body weight between lines and resulted in correlated responses for a number of traits including appetite, immune response, body composition and metabolic traits. Phenotypic data on growth and other correlated traits were collected from more than 800 F2 individuals. Genome scans using 145 markers on 26 linkage groups have identified QTLs affecting growth and correlated responses to selection for 56-day body weight. No major QTL explaining a large portion of phenotypic variation in growth was revealed in this study.

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Lainé, Annick. « Management coopératif et gouvernance coopérative : un trait d'union pour un développement soutenable des SCOP : analyse des pratiques de SCOP TPE-PME en Rhône Alpes ». Thesis, Montpellier 1, 2011. http://www.theses.fr/2011MON10047.

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Ce travail de recherche doctoral a pour objet l'étude des relations entre la Gouvernance, le Management des Ressources Humaines et la Stratégie des SCOP. Ces entreprises coopératives, au projet politique originel et original, s'organisent à partir de valeurs issues du XIX ème siècle que sont la solidarité, la propriété collective inter-générationnelle et l'équité, eu égard à leur triple filiation économique, politique et sociale.L'identification de risques de tensions et d'éclatements inhérents à ce type de gouvernance hybride fait appel à un management adapté pour animer une organisation de salarié-e-s -associé-e-s majoritaires en co-responsabilité d'une organisation coopérative.Cette problématique à la croisée du terrain et de la littérature, s'inscrit dans une démarche innovante d'approche triptyque pour une méthodologie qualitative.L'analyse des pratiques et des discours recueillis auprès de gérant-e-s de 16 SCOP TPE PME de Rhône Alpes et d'animateurs du secteur coopératif a révélé d'une part des freins et des leviers et d'autre part des éléments de contingence au Développement Coopératif Soutenable des SCOP. Ces résultats ont permis l'élaboration d'un idéal type de Management Coopératif et de Développement Coopératif Soutenable complétés par le SCCORRET et la pyramide de l'équilibre coopératif, outils de gestion coopératifs proposés pour prévenir les risques de tensions individuels et collectifs et l'établissement du lien existant entre Gouvernance Coopérative-Management Coopératif et Développement Coopératif
This doctoral research aims to study the relationship between Governance, Human Resource Management and Strategy of SCOP. These co-operative enterprises have an original and innovative political project and are beneficiaries of a triple linage of economic, political & social nature. Their values which derived from the nineteenth century are of solidarity, collective inter-generational ownership and equity.The identification of risks of tension and disintegration inherent to such an hybrid form of governance calls for a adequate management to run a co-operative organisation where worker members have a majority vote in co-responsibility.This issue emerging from both the field and the literature is studied in an innovative triptych approach based on a qualitative methodology. The analysis of practices and speeches - gathered from managers of 16 micro co-operatives and small & medium co-operatives of Rhône Alpes and from leaders of the co-operative sector – has revealed, on one hand, brakes and levers and on the other hand, contingency elements to a sustainable co-operative development of SCOP.These results have allowed the development of an ideal type of co-operative management and sustainable co-operative development based on co-operative management tools designed to prevent the risk of individual and collective tensions and to strenghthen the link between co-operative governance, co-operative management and co-operative development

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Oken, Barry S. « A Systems Approach to Stress and Resilience in Humans : Mindfulness Meditation, Aging, and Cognitive Function ». PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/2700.

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Psychological stress is common and contributes to many physical and mental health problems. Its effects are mediated by a complex neurobiological system centering in the brain with effectors including autonomic nervous system, hypothalamic-pituitary-adrenal axis, inflammatory system, and gene expression. A stressor pushes the human physiological system away from its baseline state towards a lower utility state. The physiological system may return towards the original state but may be shifted to a lower utility state. While some physiological changes induced by stressors may benefit health, chronic stressors usually have negative effects on health. In contrast to this stressor effect is the system's resilience which influences its ability to return to the high utility attractor basin following a perturbation by increasing the likelihood and/or speed of returning to the baseline state following a stressor. Age-related cognitive decline is a major public health issue with few preventative options. Stress contributes to this cognitive decline, and mindfulness meditation (MM) is a behavioral intervention that reduces stress and stress reactivity in many health conditions. A randomized clinical trial was performed to determine if MM in older adults would improve measures of cognitive function, as well as psychology and physiology, and to determine what factors might predict who would improve. 134 at least mildly stressed 50-85 year olds were randomized to a MM intervention or a wait-list control. Outcome measures included a broad cognitive function battery with emphasis on attention and executive function, self-rated psychological measures of affect and stress, and physiological measures of stress. Self-rated measures related to negative affect and stress were all significantly improved as a result of the MM intervention compared to wait-list control. There were no changes in cognition, salivary cortisol, and heart rate variability. Potential explanations for the discrepancy between the beneficial mental health outcomes and lack of impact on cognitive and physiological outcomes are discussed. To determine which factors predict MM responsiveness, a responder was defined by determining if there was a minimum clinically important improvement in mental health. Predictors included demographic information and selected self-rated baseline measures related to stress and affect. Classification was performed using decision tree analysis. There were 61 responders and 60 non-responders. Univariate statistical analysis of the baseline measures demonstrated significant differences between the responder and non-responders in several self-rated mental health measures. However, decision tree was unable to achieve a reliable classification rate better than 65%. A number of future research directions were suggested by this study, including to optimize the MM intervention itself, to better select participants who would benefit from MM, and to improve the outcome measures perhaps by focusing on decreased reactivity to stressful events. Finally, a less well-defined but always present future research direction is the development of better models and better quantitative analysis approaches to the multivariate but dynamically limited human empirical data that can be practically collected.

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Meyers, Tom. « The effect of the Reaset Approach on the autonomic nervous system, state-trait anxiety and musculoskeletal pain in patients with work-related stress : A pilot study ». Bachelor's thesis, Dresden International University, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-204179.

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Background: Work-related stress (WRS) is associated with musculoskeletal pain (MSP), changes in the autonomic nervous system (ANS) and anxiety. Objective: To determine the feasibility of a follow-up study and treatment efficacy of the Reaset Approach on MSP, ANS and State-Trait anxiety. Methods: 15 subjects with WRS and MSP were assigned into 3 groups (Body, Head-Neck, Head-Neck-Body). Each group received a single 25 minute ‘Reaset Approach’ intervention. Heart rate variability (HRV), electro-dermal activity (EDA), State Trait Anxiety (STAI) and MSP were measured. Results: HRV parameters: SDNN increased in 13 of 15 subjects while SD1 and SD2 increased in 12 of 15 subjects. EDA reduced in 10 of 14 subjects. State Anxiety reduced in all subjects and Trait Anxiety reduced in 14 of 15 subjects. MSP reduced in all subjects after the intervention and were still lower three days afterwards. Conclusions: This pilot study determined that a follow-up study can ensue provided minor modifications are implemented and that the ‘Reaset Approach’ has an influence on the ANS, anxiety and MSP. Results do differ between groups. The intervention groups including the head and neck modalities demonstrated better results
Hintergrund: Arbeitsbedingter Stress (ABS) ist verbunden mit muskelschmerzen, Veränderungen im autonomen Nervensystem (ANS) und Angst. Ziel: Machbarkeit einer Follow-up-Studie und Wirksamkeit der Behandlung des Reaset Ansatzes auf ANS, Muskelschmerzen und State und Trait- Angst bestimmen. Methoden: 15 Patienten mit ABS und Muskelschmerzen wurden in 3 Gruppen eingeteilt (Körper, Kopf-Hals, Kopf-Hals-Körper). Jede Gruppe erhielt eine einzige 25 Minuten dauernde 'Reaset Approach’-Behandlung. Herzfrequenzvariabilität (HRV), elektro-dermale Aktivität (EDA), State-Trait-Angstsinventar (STAI) und Muskelschmerzen (SF-MPQ) wurden gemessen. Ergebnisse: Die HRV-wert: SDNN ist bei 13 von 15 Probanden erhöht, während SD1 und SD2 bei 12 von 15 Probanden zugenommen hat. EDA war bei 10 von 14 Probanden reduziert. Die State-Angst hat bei allen Probanden und die Trait-Angst bei 14 der 15 Probanden abgenommen. Muskelschmerzen waren bei alle Probanden anschließend an und drei Tage nach der Intervention reduziert. Schlussfolgerung: Diese Pilotstudie hat gezeigt, dass eine Follow-up-Studie fortgesetzt werden kann, sofern kleinere Änderungen durchgeführt werden. Die 'Reaset Approach’ hat einen günstigen Einfluss auf die ANS, State-Trait-Angst und Muskelschmerzen. Ergebnisse zwischen den Gruppen sind unterschiedlich. Die Interventionsgruppen mit einschließlich der Kopf-Hals-Modalitäten zeigten bessere Ergebnisse

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Fry, Jann E. « A PLANT TRAIT-BASED APPROACH TO EVALUATE THE ABILITY OF NATIVE C₃ AND C₄ GRASSES TO RESTORE FUNCTIONALITY TO A REMNANT BLUEGRASS SAVANNA-WOODLAND IN KENTUCKY, USA ». UKnowledge, 2014. http://uknowledge.uky.edu/biology_etds/20.

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Temperate Midwestern oak savannas are considered imperiled ecosystems with < 1 % remaining since the time of European settlement and are identified as critical areas for preservation. Restoration of Midwestern oak savannas is challenging due to the lack of accurate historical data, few intact remnants remaining to study, and lack of restoration ecology studies. A plant trait-based approach was used to evaluate the ability of six C3 and three C4 native bunchgrasses to restore functionality to a remnant savanna–woodland of the Bluegrass Region of Kentucky. The response and effect framework was used to assess the response of the nine native grasses according to the habitat filters of interannual precipitation, inter- vs. intra-specific competition, and simulated grazing. The effect traits associated with plant-soil nitrogen and carbon cycling were also assessed. The response traits of interannual competition and inter- vs. intra-specific competition along with the effect traits plant-soil nitrogen and carbon cycling were measured in a monoculture experiment conducted at Griffith Woods WMA. The simulated grazing or clipping experiment was conducted over three months in a heated greenhouse experiment. Four of the C3 species were of the genus Elymus which had significant differences in life history traits compared to the other species and made them particularly well adapted to the Bluegrass Savanna-Woodland. The Elymus species were not well adapted to the most intense clipping treatment. For the other two C3 species, C. latifolium would be a better competitor than D. clandestinum under normal conditions. D. clandestinum had the most number of plastic traits and was the only species to exhibit all three grazing strategies. Comparing the C4 species, T. flavus and P. anceps grew well in the monoculture but A. virginicus did not. The life history traits of A. virginicus does not make this species a good candidate for restoration at this site. The three C4 species were well adapted to clipping. The results of this study suggest that the C3 species, particularly the Elymus, are well adapted to the eutrophic mesic conditions of the Bluegrass Savanna-Woodland, and that the C4 species are better adapted to disturbance.

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Iltis, Corentin. « Effets du réchauffement climatique sur la performance d’un ravageur des cultures et impact sur les relations tritrophiques ». Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCK051.

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Le réchauffement climatique va avoir des répercussions profondes sur les organismes vivants, en particulier les ectothermes comme les insectes, dont la physiologie et le comportement sont intimement liés à la température de leur environnement. Cette thèse propose d’étudier, par voie expérimentale, les conséquences du réchauffement climatique sur la performance d’un ravageur majeur de la vigne en Europe, l’eudémis (Lobesia botrana), et les conséquences pour l’interaction entre ce phytophage et les niveaux trophiques associés, en particulier les ennemis naturels (parasitoïdes). Les travaux se focalisent sur trois facettes du réchauffement climatique : une augmentation de température moyenne, une altération de l’amplitude thermique journalière, et l’occurrence d’une vague de chaleur.Les résultats attestent d’un impact des températures sur les traits reliés à la performance larvaire (capacités de défense des chenilles contre les ennemis naturels) et sur la reproduction des adultes, ainsi que sur l’interaction entre ce ravageur et un parasitoïde oophage. Par ailleurs, une importante variabilité de réponses thermiques est observée entre traits et parfois entre facettes du changement climatique, laissant suggérer des conséquences complexes de ce dernier sur la dynamique des populations du ravageur. Ainsi, prédire la réponse d’une espèce au réchauffement climatique nécessite d’adopter une vision relativement intégrative de la biologie de cette espèce, ainsi que de la complexité des changements se produisant au niveau de l’environnement thermique de l’organisme
Global warming poses a major challenge to living organisms, particularly for ectothermic animals like insects, whose physiology and behaviour are closely related with direct thermal surroundings. This thesis aims at experimentally investigating the impacts of climate change on the overall performance of a major grapevine pest, the European grapevine moth (Lobesia botrana), and the associated consequences for interactions involving this phytophagous insect and adjacent trophic levels, more specifically natural enemies (parasitoids). The experiments conducted focus on three facets of climate change: an increase in mean temperature, an alteration of daily thermal range, and the occurrence of heat waves as extreme thermal events.Results highlight an impact of temperatures on both life-history traits related with larval performance (defensive abilities of caterpillars) and adult reproductive success, with demonstrated repercussions for the interaction between this pest and an oophagous parasitoid. Furthermore, they reveal an important variability of thermal responses occurring among traits and even facets of climate change, thereby suggesting complex consequences of this phenomenon in terms of pest population dynamics. Hence, predicting a species response to climate change requires adopting an integrative perspective of the biology of the focal species while considering the complexity of changes occurring in insect direct thermal environment

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Terseleer, Lillo Nathan. « Bottom-up and top-down controls of diatoms in the Belgian coastal zone, Southern North Sea : combining plankton functional type modelling and trait-based approaches ». Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209321.

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Les diatomées sont une composante majeure des écosystèmes marins et sont caractérisées par une grande diversité. L’objectif général de cette thèse est d’étudier les facteurs de contrôle des diatomées dans la Zone Côtière Belge (ZCB). Pour ce faire, la modélisation par groupes fonctionnels et l’approche basée sur les traits sont combinées :la première fournit un cadre écosystémique utile pour étudier les interactions des diatomées avec les compartiments biotiques et abiotiques de l’écosystème, et la seconde permet de représenter de façon efficace leur diversité fonctionnelle.

Dans un premier temps, puisque la taille est reconnue comme un trait majeur affectant de nombreux aspects de la valeur sélective du phytoplancton, la dépendance au biovolume de différents traits des diatomées a été établie sur base d’observations disponibles dans la littérature. Cette revue a montré qu’un compromis sépare les diatomées sur base de leur biovolume :les petites espèces sont meilleures compétitrices pour l’acquisition des ressources mais plus sensibles au broutage, et inversement.

Sur cette base, un ré-analyse d’un jeu de données incluant des comptages et mesures de biométrie avec l’identification de 68 taxons dans la ZCB entre 1992 et 2000 a été réalisée, avec une attention particulière pour la structure en termes de taille de la communauté de diatomées. Un regroupement des diatomées en fonction de leur biovolume a été réalisé sur base de leur évolution saisonnière typique. L’analyse de leur évolution temporelle suggère que la communauté des diatomées est composée d’assemblages avec une évolution saisonnière et interannuelle distinctes qui répondent vraisemblablement différemment aux conditions environnementales.

Afin d’étudier plus en profondeur les facteurs environnementaux contrôlant la structure en termes de taille de la communauté des diatomées dans la ZCB, le module diatomées du modèle MIRO, qui représente l’écosystème planctonique de la ZCP, a été modifié afin d’inclure les dépendances à la taille de quatre traits des diatomées. Cet outil reproduit correctement l’évolution saisonnière du biovolume moyen de la communauté, qui est caractérisé par de plus petites diatomées au printemps qui maximisent l’acquisition de ressources tandis que la prévalence du broutage en été induit une transition vers des espèces plus grandes. Le modèle a également été exploité pour étudier la gamme de tailles viables dans la ZCB en fonction des conditions environnementales.

Les résultats du modèle basés sur les traits ont ensuite été analysés sur la période 1992-2000. Les simulations ont mis en évidence les interactions complexes entre les processus physiques, de contrôles par les ressources et par le broutage, qui sont susceptibles de déterminer la variabilité interannuelle de la structure en termes de taille des diatomées dans la ZCB. La comparaison de ce modèle adaptatif avec un modèle plus conventionnel qui ne représente pas de diversité interne aux diatomées suggère que le premier produit une réponse légèrement plus flexible que le dernier, mais que la rigidité de la réponse simulée demeure un problème avec le modèle adaptatif qui reste incapable de représenter des évènements extrêmes de biomasse ou de structure de la communauté. Cela suggère que des développements supplémentaires du modèle sont nécessaires, en particulier du module zooplancton.

Finalement, une fonction écologique particulière est abordée dans une dernière section de cette thèse :la production d’une neurotoxine par certaines diatomées du genre Pseudo-nitzschia. Cette fonction a été incluse comme un métabolisme secondaire dans un modèle idéalisé de la croissance de Pseudo-nitzschia afin d’étudier les facteurs contrôlant la production de la toxine. Il est notamment montré que l’environnement lumineux est déterminant lorsque les conditions menant à la production de toxine sont rencontrées.

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Diatoms are a key component of marine ecosystems and are characterized by an important diversity. The general objective of this thesis is to investigate the bottom-up and top-down controls of diatoms in the Belgian Coastal Zone (BCZ). This is done through the integration of their functional diversity into a coherent framework. In order to achieve this, Plankton Functional Type modelling and trait-based approaches are combined: the former provides an ecosystem context convenient to study the interactions of diatoms with biotic and abiotic compartments, and the latter allows an efficient representation of their functional diversity.

As a first step, since size is recognized as a master trait shaping many aspects of phytoplankton fitness, the cell volume dependences of diatom functional traits were compiled from observations available in the literature. This review showed that a trade-off distinguishes diatoms on the basis of their cell volume: smaller species are better competitor for resource acquisition but sensitive to grazing, and inversely.

On this basis, a re-analysis of a dataset including diatom cell counts and biometry with the identification of 68 taxa in the BCZ over the 1992-2000 period was carried out, with a focus on the size structure of the diatom community. A clustering of diatoms according to their cell volume was realized on the basis of their average seasonality. Investigation of their time evolution suggested that the diatom community in the area is composed of assemblages with distinct seasonal and interannual evolution that likely respond differently to environmental conditions.

In order to further investigate the bottom-up and top-down constrains on the size structure of the diatom community in the BCZ, the diatom module of the MIRO model, which represents the planktonic ecosystem of the BCZ, was modified in order to accommodate size-dependences of four diatom functional traits. This tool adequately reproduced the seasonal evolution of the mean cell volume of the diatom community, which is characterized by smaller diatoms in spring that maximize resource acquisition while the prevalence of grazing pressures in summer induces a shift towards larger species. The model was also used to investigate the range of viable diatom sizes in response to the bottom-up and top-down pressures in the BCZ.

Results of the trait-based adaptive model were then analysed over the 1992-2000 period. Simulations evidenced the complex interactions between physical, bottom-up and top-down processes that are likely to govern the interannual variability in the size structure of diatom in the area. Comparison of the adaptive model with a more conventional model resolving no diversity within diatoms suggested that the former produces a slightly more flexible response than the latter, but showed that the rigidity of the simulated response persists with the adaptive model which remains unable to catch extreme biomass and community structure events. This calls for further developments of other compartments of the model, more particularly zooplankton.

Finally, a peculiar ecological function is addressed on its own in the last section of this thesis: the toxigenicity of some species of the genus Pseudo-nitzschia. This function was added as a secondary metabolism in an idealized model of Pseudo-nitzschia growth in order to investigate the factors affecting toxin production. It notably showed that light was determinant under conditions leading to its production.

Doctorat en Sciences agronomiques et ingénierie biologique
info:eu-repo/semantics/nonPublished

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Fritz, Sarah-mee. « A Mixed Methods Approach to Exploring Social Support and Resilience in Coping with Stigma and Psychological Distress among HIV-Positive Adults ». Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc1011870/.

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Since its emergence in the U.S., HIV has been a stigmatized illness. People living with HIV (PLH) are a minority and prone to psychological distress and poor mental health outcomes due to HIV-related stigma. PLH who identify with another minority group in addition to being HIV-positive (e.g., gay, African-American) experience multiple forms of oppression or layered stigma. Affirmative social support and resilience are negatively associated with HIV-stigma and are important coping resources for PLH. We used an explanatory sequential mixed methods design study involving a quantitative survey phase and a qualitative interview phase. We explored whether social support and resilience (Positive Psychological Resources) mediate or moderate the relationship between HIV Stigma and Psychological Distress among HIV-positive adults using partial least squares (PLS) path modeling and multiple regressions. Via PLS, we found Positive Psychological Resources partially mediated the relationship between HIV Stigma and Psychological Distress: the path between HIV Stigma and Psychological distress reduced (from t = 5.49, p = .000 to t = 2.39, p = .000) but remained statistically significant. Similarly, via regression, the Sobel test was significant (Sobel = .26, SE = .07, z = 3.63, p = .000). However, moderation was not found (HIV Stigma x Positive Psychological Resources β = .05, t = .66, p = .508). Overall, our quantitative survey and qualitative interview data were consistent. We anticipate that our findings will inform strengths-based therapeutic interventions to mitigate stress and stigma among PLH.

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LaChausse, Robert Gerald. « Measuring resiliency in adolescence : The press scale of resiliency ». CSUSB ScholarWorks, 1998. https://scholarworks.lib.csusb.edu/etd-project/1663.

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Boyé, Aurélien. « Diversité taxinomique et fonctionnelle des habitats benthiques dans l'espace et dans le temps : une perspective régionale et décennale Constancy despite variability : Local and regional macrofaunal diversity in intertidal seagrass beds ?, in Journal of Sea Research 130, December 2017 ». Thesis, Brest, 2018. http://www.theses.fr/2018BRES0110.

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Ce travail de thèse s’appuie sur les données d’un suivi à long-terme mené à une échelle régionale pour mieux appréhender les facteurs gouvernant la diversité des fonds marins côtiers. En considérant de multiples échelles spatiales et temporelles ainsi que différentes facettes de la diversité de ces communautés, l’objectif principal a été de fournir des connaissances permettant de mieux prédire les potentielles réponses des communautés benthiques face aux changements environnementaux à venir. Cette thèse s’inscrit en particulier dans un contexte de la menace de l’homogénéisation des fonds marins et de la disparition à large échelle des habitats biogéniques, réservoirs de biodiversité formés par des espèces fondatrices. La comparaison de deux de ces habitats, les herbiers de Zostères intertidaux et les bancs de mäerl subtidaux, à des sédiments dépourvus d’espèces fondatrices a mis en évidence le rôle fondamental de ces habitats biogéniques dans le maintien de la diversité et du fonctionnement des fonds marins à long-terme. Ils contrôlent profondément les dynamiques temporelles des communautés et leurs capacités de réponse aux variations des conditions environnementales, assurent une plus grande stabilité des structures spatiales des communautés à une échelle régionale. Ils semblent par-là essentiels au maintien à long-terme des fonctions écologiques auxquelles contribuent les espèces benthiques. Cependant, ce travail montre que ces espèces fondatrices opèrent selon des mécanismes différents et que les implications en terme de vulnérabilité des communautés sont donc aussi différentes. Cette étude montre enfin qu’au sein d’un habitat donné, la richesse locale des communautés est relativement stable dans l’espace et le temps et met en évidence le besoin de caractériser les variations de compositions de communautés pour guider les actions de conservations à larges échelles. À ce titre, et à l’échelle régionale, les variations de composition contribuent à une richesse taxinomique et fonctionnelle dans les sédiments dépourvus d’espèces fondatrices aussi importante que dans les habitats biogéniques.Ce résultat impose de réévaluer la valeur de conservation qui pourrait leur être attribué de part leur richesse locale limitée. Les suivis à grandes échelles spatiales et temporelles sont dans ce contexte essentiels pour fournir un lien entre les connaissances empiriques et théoriques existantes à des échelles locales, et les échelles supérieures auxquelles s’intéressent les politiques de conservation
This thesis takes advantage of long-term monitoring data covering a regional scale to better apprehend the maindrivers of the diversity of coastal seafloors. Through consideration of multiple spatial and temporal scales and different facets o fcommunity diversity, the main objective of this work was to provide a better predictive understanding of the responses of benthic communities to environmental changes. In particular, this thesis addressed the potential consequences of the on-going homogenisation of the seafloor and the global loss of biogenic habitats, havens of diversity made by foundation species. Through comparison of two such habitats, intertidal seagrass meadows and subtidal maerl beds, with bare sediment devoid of foundationspecies, this thesis has highlighted the key role of biogenicstructures for long-term maintenance of the diversity andfunctioning of benthic communities. Indeed, these habitats mediate the dynamics and responses of benthic communities to environmental conditions, ensure a greater stability of their spatial structures at regional scale, and appeared essential for the long-term maintenance of the ecological functions benthic invertebrates are associated with. This work also highlighted that foundation species may affect benthic communities through different mechanisms, and that has implications on the structure and vulnerability of these communities. Lastly, this the sisemphasized a strong spatial and temporal stability of community richness despite important underlying changes in composition and there by stressed the need to better characterise these compositional variations to guide conservation. These variations contributed, for instance, to an unexpectedly high taxonomic and functional richness of bare sediment at regional scale,similar to those of biogenic habitats, despite being locally depauperate. Overall, broad-scale monitoring programs are fundamental assets to bridge local empirical and theoretical ecological knowledge to the broader scales at which society manage and benefits from natural ecosystems

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Terrien, Sarah. « Approche psychopathologique dimensionnelle de la schizophrénie et du trouble bipolaire : exploration des processus cognitifs d’intégration des informations contextuelles sémantiques et sémantico-émotionnelles, études en potentiels évoqués ». Thesis, Reims, 2016. http://www.theses.fr/2016REIML009.

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Ce travail de thèse s’inscrit dans une approche dimensionnelle de la psychopathologie et son objectif est d’apporter de nouvelles connaissances au champ de recherche qui considère l’existence d’un continuum entre schizophrénie et trouble bipolaire ainsi qu’entre traits de personnalité et pathologies. Afin d’explorer ces continuums, nous avons étudié, grâce à la méthode des potentiels évoqués cognitifs et l’étude de certaines de leurs composantes (N400, LPC), les processus neurocognitifs sous-tendant l’intégration d’un contexte sémantique et sémantico-émotionnel dans la schizophrénie, le trouble bipolaire, les traits de personnalité schizotypique et les traits de personnalité hypomaniaque. Premièrement, nous avons montré, que les patients schizophrènes stabilisés et les patients bipolaires euthymiques présentent des patterns de modulation de la N400 différents lors de tâches impliquant l’intégration d’un contexte sémantique ou sémantico-émotionnel. Néanmoins, ces résultats en défaveur de l’existence d’un continuum entre schizophrénie et trouble bipolaire pourraient être la conséquence de l’absence de symptomatologie commune entre nos deux échantillons de patients. Deuxièmement, les résultats des études portant sur la population pathologique et ceux des études portant sur la population générale présentant des traits de personnalité semblent en faveur de l’existence d’un continuum entre population générale et pathologie. En effet, les personnes présentant des traits de personnalité hypomaniaque présentent des similitudes dans les atteintes des processus neurocognitifs sous-tendant l’intégration d’un contexte sémantique et sémantico-émotionnel avec les patients bipolaires, et les personnes présentant des traits de personnalité schizotypique présentent des similitudes dans les atteintes des processus neurocognitifs sous-tendant l’intégration d’un contexte sémantico-émotionnel avec les patients schizophrènes. L’ensemble de nos résultats associés à ceux de la littérature semblent en faveur d’une approche dimensionnelle de la psychopathologie bipolaire et schizophrénique où les symptômes, davantage que le diagnostic, doivent être envisagés comme le point central du continuum
This work is part of a dimensional approach of the psychopathology. Its goal is to bring new knowledge to the field of research that considers the existence of a continuum between schizophrenia and bipolar disorder as well as between personality traits and pathologies. In order to explore these continuums, we have studied, thanks to event-related potential method and the study of N400 and LPC components, neurocognitive processes involved in the integration of semantic and semantico-emotional context in schizophrenia, bipolar disorder, schizotypal personality traits and hypomanic personality traits. We have first demonstrated that stabilized schizophrenic patients and euthymic bipolar patients have different patterns of the N400 modulation during tasks involving semantic and semantico-emotional integration. However, these results against the existence of a continuum between schizophrenia and bipolar disorder could be due to the lack of common symptoms in both samples. Secondly, the results of our studies dealing with clinical population and those dealing with general population with personality traits seem to be in favor to the existence of a continuum between general population and pathology. As a matter of fact individuals with hypomanic personality traits have similitude with bipolar patients in disturbance in neurocognitive processes involved in the integration of semantic and semantico-emotional context. Furthermore, individuals with schizotypal personality traits have common difficulties with schizophrenic patients in neurocognitive processes involved in semantico-emotional context integration. The results of our investigation, combined with those in the literature, are in favor of a dimensional approach of schizophrenic and bipolar psychopathology. And this approach is more about considering the symptoms as the central point of the continuum rather than the diagnostic

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Thurston, David Frank. « A Proactive Approach to Train Control ». Diss., Temple University Libraries, 2012. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/181175.

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Electrical Engineering
Ph.D.
The main objective in optimizing train control is to eliminate the waste associated with classical design where train separation is determined through the use of "worst case" assumptions to calculate Safe Braking Distances that are invariant to the system. In fact, the worst case approach has been in place since the beginning of train control systems. Worst case takes the most conservative approach to the determination of train stopping distance, which is the basis for design and capacity of all train control systems. This leads to stopping distances that could be far more than actually required under the circumstances at the time the train is attempting to brake. A new train control system is proposed that utilizes information about the train and the conditions ahead to optimize and minimize the Safe Braking Distance. Two methods are proposed to reduce safe braking distance while maintaining an appropriate level of safety for the system. The first introduces a statistical method that quantifies a braking distance with various hazards levels and picks a level that meets the safety criteria of the system. The second method uses train mounted sensors to determine the adhesion level of the wheel and rail to determine the appropriate braking rate for the train under known circumstances. Combining these methods provides significant decreases in Safe Braking Distances for trains. A new train control system is utilized to take advantage of these features to increase overall system capacity.
Temple University--Theses

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Moor, Helen. « Function follows Form : Trait-based approaches to climate change effects on wetland vegetation and functioning ». Doctoral thesis, Stockholms universitet, Stockholm Resilience Centre, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-133488.

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Climate change and habitat fragmentation are altering the structure and functioning of plant communities world-wide. Understanding how, why and with what consequences are major challenges of ecology today. Trait-based approaches focus on functional rather than taxonomic identity to facilitate process-based explanation and prediction. This thesis develops new ways of operationalising traits to understand plant community responses to the environment and community effects on ecosystem functioning and services. Wetlands, distinct in nature and patchy in their distribution, serve as a natural laboratory to extend plant trait theory and as inspiration for metacommunity modelling. The first part of the thesis (Papers 1 and 2) focuses on wetland plant traits in relation to current and future environmental conditions, ecosystem functioning and ecosystem services. Paper 1 surveys the state of knowledge regarding (i) ultimate and proximate drivers of wetland plant community functional composition, trait covariation and responses of individual traits along gradients, as well as (ii) trait effects on the sets of ecosystem properties and processes that underlie the generation of three key wetland ecosystem services (regulation of water flow, water quality, and climate). Paper 2 modifies species distribution modelling to predict future changes in plant community trait distributions due to climate change in central Sweden, which allows a qualitative estimate of changes in ecosystem service potential. Climate change induced functional changes may benefit water quality and flow regulation provided by fens and riparian wetlands, but compromise carbon sequestration capacity in bogs. The second part of the thesis (Papers 3 and 4) develops trait-based metacommunity models to study the interplay of local and regional dynamics on species, community and whole-metacommunity responses to climate change. Paper 3 finds model assumptions about species dispersal capacity to strongly influence predictions of diversity loss following climate change. While differences in species dispersal capacity drastically increase predicted extinction risk, more realistic models based on an empirically derived seed mass – seed number trade-off strongly moderate these predictions. Without considering fitness effects of covarying traits, models that include variable dispersal capacities thus might overestimate extinction risk from climate change. Paper 4 studies the development and recovery of the regional average trait-lag of response trait distributions, as a direct measure of the instantaneous realised metacommunity response to temperature change with implications for levels of ecosystem functioning. The dynamical response jointly depended on local response capacity and regional adaptive re-organisation via species range shifts. Where habitat was scarce, connectivity network properties mediated response capacity and may guide conservation priorities. This thesis makes contributions to plant trait ecology, wetland functional ecology, ecosystem service science and metacommunity theory. As a whole it furthers progress towards a predictive ecology that can bridge scales from individual physiology to ecosystem dynamics and anticipate global change effects on biodiversity and ecosystem functioning.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 3: Manuscript. Paper 4: Manuscript.

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Barton, Andrew David. « Trait-based approaches to marine microbial ecology ». Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/69465.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references.
The goal of this thesis is to understand how the functional traits of species, biotic interactions, and the environment jointly regulate the community ecology of phytoplankton. In Chapter 2, I examined Continuous Plankton Recorder observations of diatom and dinoflagellate abundance in the North Atlantic Ocean and interpreted their community ecology in terms of functional traits, as inferred from laboratory- and field-based data. A spring-to-summer ecological succession from larger to smaller cell sizes and from photoautotrophic to mixotrophic and ieterotrophic phytoplankton was apparent. No relationship between maximum net growth rate and cell size or taxonomy was found, suggesting that growth and loss processes nearly balance across a range of cell sizes and between diatoms and dinoflagellates. In Chapter 3, I examined a global ocean circulation, biogeochemistry, and ecosystem model that indicated a decrease in) phytoplankton diversity with increasing latitude, consistent with observations of many marine and terrestrial taxa. Ii the modeled subpolar oceans, seasonal variability of the environment led to the competitive exclusion of phytoplankton with slower growth rates and to lower diversity. The relatively weak seasonality of the stable subtropical and tropical oceans in the global model enabled long exclusion timescales and prolonged coexistence of multiple phytoplankton with comparable fitness. Superimposed on this meridional diversity decrease were "hot spots" of enhanced diversity in soc regions of energetic ocean circulation which reflected a strong influence of lateral dispersal. In Chapter 4, I investigated how small-scale fluid turbulence affects phytoplankton nutrient uptake rates and community structure in an idealized resource competition model. The flux of nutrients to the cell and nutrient uptake are enhanced by turbulence, particularly for big cells in turbulent conditions. Yet with a linear loss form of grazing, turbulence played little role in regulating model community structure and the smallest cell size outcompeted all others because of its significantly lower R* (the minimum nutrient requirement at equilibrium). With a quadratic loss form of grazing, however, the coexistence of many phytoplankton sizes was possible and turbulence played a role in selecting the number of coexisting size classes and the dominant size class. The impact of turbulence on community structure in the ocean may be greatest in relatively nutrient-deplete regions that experience episodic inputs of turbulence kinetic energy.
by Andrew David Barton.
Ph.D.

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Krapohl, Eva Maria Laura. « Multi-variable approaches to polygenic trait prediction ». Thesis, King's College London (University of London), 2017. https://kclpure.kcl.ac.uk/portal/en/theses/multivariable-approaches-to-polygenic-trait-prediction(1e69a4a3-f89b-4646-980e-02031d5c23d3).html.

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Robust evidence for the polygenicity and genetic correlations of complex traits across the phenome suggests both the necessity of polygenic instruments and the value of multi-trait prediction models. This thesis used multi-variable approaches in four papers and along two main threads: Multi-variable approaches to trait prediction A primary goal of polygenic scores, which aggregate effects of trait-associated variants discovered in genome-wide association studies (GWAS), is to estimate individual-specific genetic propensities to predict trait variation. This is typically achieved using one polygenic score predicting one outcome. Extending this to a multi-variable approach, a ‘phenome-wide analysis of genome-wide polygenic scores’ mapped associations between 13 polygenic scores created from GWAS for psychiatric disorders and cognitive traits and 50 behavioural traits. Extending the multi-variable approach further, a multi-polygenic score approach was employed to increase prediction by exploiting the joint power of multiple discovery GWAS in the same model. A regularised regression model combining summary statistics of 81 trait GWAS improved out-of-sample prediction of three child outcomes over the best single-predictor model. Multi-variable approaches to gene-environment correlation Although geneenvironment correlation is widely investigated by family studies and recently by SNP-heritability studies, the possibility that genetic effects on traits capture environmental risk factors or protective factors has been neglected by polygenic prediction models. First, a study using genome-wide SNP-heritability estimation and polygenic score analysis provided the first molecular evidence for substantial genetic influence on differences in children’s educational achievement and its association with family socio-economic status. Second, covariation between offspring trait-associated polygenic variation and a wide range of parent-mediated environmental exposures was estimated. For this, a mixed linear model estimated the effects of multiple polygenic scores on each environmental exposure while controlling for overall relatedness by fitting the effects of all SNPs as random effects. Findings illustrate the relevance of gene-environment correlation for polygenic prediction models. Taken together, the analyses illustrate the value of multi-variable approaches to complex trait prediction, as well as their current limitations and future potential.

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Zablotski, Yury [Verfasser]. « Optimality and trait based approaches to sympatric speciation and sympatric co-evolution of predator and prey traits in marine plankton / Yury Zablotski ». Kiel : Universitätsbibliothek Kiel, 2014. http://d-nb.info/105432820X/34.

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Dalton-Brits, E., et M. Viljoen. « Personality traits and learning approaches : are they influencing the learning process ? » Journal for New Generation Sciences, Vol 8, Issue 3 : Central University of Technology, Free State, Bloemfontein, 2010. http://hdl.handle.net/11462/565.

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Published Article
The relationship between the big five personality traits, Extraversion, Agreeableness Neuroticism, Conscientiousness and Openness to Experience and deep and surface approaches to learning forms the basis of this article. The findings of a research study in this milieu will be presented to prove that earlier studies in this field have been upheld, but that an important deviation has occurred on certain levels of personality. A students way of learning implies the type of learning that is taking place. Ultimately we as lecturers want to encourage deep learning as this stimulates retention of information, important in production of students that are ready for employment.

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Rocci, Lisa. « Locomotion : A Cinematic Approach ». Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/32428.

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The landscape is not static, but perceived dynamically and should be designed for the unique sorts of movement that occur. Within the site of Carpinteria, Californiaâ s Amtrak train station lies an opportunity to maximize public space through an investigation of those in motion at this place of convergence, including cars, busses, pedestrians, skateboarders, bicyclists, and trains. A cinematic process of design allows for exploration of distinct character movements and resulting unique perceptions of the site in terms of scale, rhythm, texture, color, and perceived desire or needs. These stories are then sculpted onto the land, recording physically threads of speed, moments of pause, and elements of fascination. The â newâ station is presented as a movie, unveiling a landscape perceived and created dynamically through the eyes of those in motion.
Master of Landscape Architecture

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Utzinger, Jürg. « Novel approaches in the control of schistosomiasis : from rapid identification to chemoprophylaxis / ». Basel : Universität Basel, 1999. http://edoc.unibas.ch/diss/DissB_5365.

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Kauppi, Arvid. « A human-computer interaction approach to train traffic control ». Licentiate thesis, Uppsala : Department of Information Technology, Uppsala University, 2006. http://www.it.uu.se/research/publications/lic/2006-005/.

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Wu, Song. « A robust approach for genetic mapping of complex traits ». [Gainesville, Fla.] : University of Florida, 2008. http://purl.fcla.edu/fcla/etd/UFE0022399.

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Petersson, Anton. « Train Re-scheduling : A Massively Parallel Approach Using CUDA ». Thesis, Blekinge Tekniska Högskola, Institutionen för datalogi och datorsystemteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-10965.

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Context. Train re-scheduling during disturbances is a time-consuming task. Modified schedules need to be found, so that trains can meet in suitable locations and delays minimized. Domino effects are difficult to manage. Commercial optimization software has been shown to find optimal solutions, but modied schedules need to be found quickly. Therefore, greedy depth-first algorithms have been designed to find solutions within a limited time-frame. Modern GPUs have a high computational capacity, and have become easier to use for computations unrelated to computer graphics with the development of technologies such as CUDA and OpenCL. Objectives. We explore the feasibility of running a re-scheduling algorithm developed specifically for this problem on a GPU using the CUDA toolkit. The main objective is to find a way of exploiting the computational capacity of modern GPUs to find better re-scheduling solutions within a limited time-frame. Methods. We develop and adapt a sequential algorithm for use on a GPU and run multiple experiments using 16 disturbance scenarios on the single-tracked iron ore line in northern Sweden. Results. Our implementation succeeds in finding re-scheduling solutions without conflicts for all 16 scenarios. The algorithm visits on average 7 times more nodes per time unit than the sequential CPU algorithm when branching at depth 50, and 4 times more when branching at depth 200. Conclusions. The computational performance of our parallel algorithm is promising but the approach is not complete. Our experiments only show that multiple solution branches can be explored fast in parallel, but not how to construct a high level algorithm that systematically searches for better schedules within a certain time limit. Further research is needed for that. We also find that multiple threads explore redundant solutions in our approach.

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De, almeida Tania. « Impact d’une espèce ingénieure de l’écosystème et son utilisation en restauration écologique : Le cas de Messor barbarus (L.) dans les pelouses méditerranéennes Above- and below-ground effects of an ecosystem engineer ant in Mediterranean dry grasslands Harvester ants as ecological engineers for Mediterranean grassland restoration : impacts on soil and vegetation A trait-based approach to promote ants in restoration ecology ». Thesis, Avignon, 2020. http://www.theses.fr/2020AVIG0358.

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L’objectif principal de cette thèse était double : (i) mesurer l’impact d’une espèce de fourmi sur son écosystème, afin (ii) d’en déduire des applications potentielles dans le domaine de la restauration écologique.Les fourmis sont parmi les organismes les plus abondants des écosystèmes terrestres et occupent des zones géographiques très variées. Elles jouent des rôles écologiques clés dans de nombreux écosystèmes comme ingénieurs du sol, prédateurs ou régulateurs de la croissance et de la reproduction des plantes. Cependant les données collectées localement sont souvent parcellaires et ne permettent pas d’avoir une vision complète de l’impact d’une espèce sur son milieu.Messor barbarus (L.), connue pour redistribuer les graines et pour modifier les propriétés physico-chimiques du sol, est largement répandue dans le Sud-Ouest de l’Europe notamment au sein des pelouses méditerranéennes. Elle pourrait donc jouer un rôle majeur dans la composition et structuration de ces pelouses caractérisées par une forte biodiversité mais dont le nombre et la superficie ont drastiquement diminué ces dernières décennies.Dans un premier temps, par une étude multi-compartiments, nous avons confirmé l’hypothèse selon laquelle M. barbarus est une ingénieure de l’écosystème au sein des pelouses méditerranéennes. Elle transforme cet habitat en modifiant, comme attendu, les propriétés physico-chimiques du sol. Ces modifications sont associées à une augmentation de la biomasse et de l’hétérogénéité des communautés végétales ainsi qu’à des changements dans les faunes épigée et endogée (abondance, occurrence et structure des communautés). De plus, M. barbarus modifie profondément les relations trophiques et non trophiques interspécifiques et entre les espèces et leur habitat. L’hétérogénéité créée à l’échelle locale par l’activité de cette fourmi, entraine une diversification des niches écologiques au sein de ces pelouses.Malgré leur rôle souvent majeur sur le fonctionnement des écosystèmes, les fourmis ne sont que très rarement considérées en restauration écologique. Sur notre site d’étude, un chantier de réhabilitation d’une pelouse sèche après une fuite d’hydrocarbures et un transfert de sol, M. barbarus a permis d’accélérer la restauration des propriétés physico-chimiques du sol mais aussi de la banque de graines à moyen terme - sept ans après la réhabilitation du site. Ces résultats font donc de cette espèce une bonne candidate en ingénierie écologique.Afin de généraliser l’utilisation des fourmis en restauration écologique, nous proposons une méthodologie à destination des gestionnaires basée sur l’utilisation de traits fonctionnels et d’histoire de vie. Pour cela nous avons évalué le potentiel des fourmis en écologie de la restauration, puis nous avons listé l’ensemble des traits connus pour affecter les compartiments abiotiques et biotiques et/ou pertinent pour effectuer un suivi du succès de la phase de restauration. La méthodologie proposée permet une première sélection des espèces potentiellement utilisables en fonction des objectifs de restauration
The main objective of this thesis was double: (i) to assess the impact of an ant species on its ecosystem, in order to (ii) deduce potential applications in the field of ecological restoration.Ants are among the most abundant organisms in terrestrial ecosystems and occupy a wide range of geographical areas. They play key ecological roles in many ecosystems as soil engineers, predators or regulators of plant growth and reproduction. However, the information collected locally is often fragmented and does not provide a complete overview of the impact of a species on its environment.Messor barbarus (L.), known to redistribute seeds and to modify the soil physico-chemical properties, is widespread in South-Western Europe, particularly in Mediterranean grasslands. Therefore, it may play a major role in the composition and structuring of these ecosystems, which are characterised by high biodiversity but whose abundance and surface area have decreased drastically in recent decades.Through a multi-compartment study, we confirmed the hypothesis that M. barbarus is an ecological engineer in Mediterranean grasslands. This species changes this habitat by modifying, as expected, soil physico-chemical properties. These modifications are associated with an increase in both biomass and heterogeneity of plant communities, as well as changes in above- and belowground fauna (abundance, occurrence and structure of communities). Messor barbarus profoundly changes trophic and non-trophic relationships within and between species and their habitat. The heterogeneity created locally by the activity of M. barbarus leads to a diversification of ecological niches within these grasslands.Despite their major role in the functioning of ecosystems, ants are rarely considered in restoration ecology. In our study site, corresponding to a dry grassland rehabilited after an oil leak and a soil transfer, M. barbarus contributed to accelerate the restoration of the soil physico-chemical properties but also of the seed bank in the medium term - seven years after the rehabilitation. These results make this species a good candidate for ecological engineering.In order to generalise the use of ants in restoration ecology, we propose a trait-based methodology for stakeholders. We evaluated the potential of ants in restoration ecology, then listed all the traits known to affect abiotic and biotic compartments and/or relevant to monitor the success of the restoration phase. The proposed methodology provides a first selection of potentially relevant species according to the restoration objectives

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Jayawardena, Mahen. « An e-Science Approach to Genetic Analysis of Quantitative Traits ». Doctoral thesis, Uppsala universitet, Avdelningen för teknisk databehandling, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-111597.

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Many important traits in plants, animals and humans are quantitative, and most such traits are generally believed to be affected by multiple genetic loci. Standard computational tools for mapping of quantitative traits (i.e. for finding Quantitative Trait Loci, QTL, in the genome) use linear regression models for relating the observed phenotypes to the genetic composition of individuals in an experimental population. Using these tools to simultaneously search for multiple QTL is computationally demanding. The main reason for this is the complex optimization landscape for the multidimensional global optimization problems that must be solved. This thesis describes parallel algorithms, implementations and tools for simultaneous mapping of several QTL. These new computational tools enable genetic analysis exploiting new classes of multidimensional statistical models, potentially resulting in interesting results in genetics. We first describe how the standard, brute-force algorithm for global optimization in QTL analysis is parallelized and implemented on a grid system. Then, we also present a parallelized version of the more elaborate global optimization algorithm DIRECT and show how this can be efficiently deployed and used on grid systems and other loosely-coupled architectures. The parallel DIRECT scheme is further developed to exploit both coarse-grained parallelism in grid systems or clusters as well as fine-grained, tightly-coupled parallelism in multi-core nodes. The results show that excellent speedup and performance can be archived on grid systems and clusters, even when using a tightly-coupled algorithm such as DIRECT. Finally, we provide two distinctly different front-ends for our code. One is a grid portal providing a graphical front-end suitable for novice users and standard forms of QTL analysis. The other is a prototype of an R-based grid-enabled problem solving environment. Both of these front-ends can, after some further refinement, be utilized by geneticists for performing multidimensional genetic analysis of quantitative traits on a regular basis.
eSSENCE

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Mirabadi, Ahmad. « Fault tolerant train navigation systems using a multisensor integration approach ». Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322911.

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Van, Pelt Jeffrey Neil. « Relationships among therapists' family background, personality traits, and therapeutic approach ». W&M ScholarWorks, 1993. https://scholarworks.wm.edu/etd/1539618687.

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This study investigated whether therapists' health of family of origin, marital adjustment, and personality traits influence their approach to therapy in systematic and measurable ways. Approach to therapy referred to: (1) relative emphasis on clients' family of origin versus current presenting problems, and (2) preference for doing individual versus conjoint marital therapy.;This study employed a survey design. Questionnaires were mailed to a national random sample of 200 counselors from the membership of the National Board for Certified Counselors (NBCC). One hundred-six were returned, for a return rate of 53%. The following instruments were used to measure the variables in the study: the Family of Origin Scale; the Locke-Wallace Marital Adjustment Test; The Adjective Check List; and the Therapeutic Focus Scale, an instrument created by the author for this study.;The results were not statistically significant for any of the hypotheses in the study. However, the relationship between therapists' family of origin and approach to therapy approached significance. That is, there was a trend for therapists from healthier families of origin to focus more on clients' current presenting problems, and for therapists from less healthy families of origin to focus more on clients' families of origin. An unexpected finding was that therapists who held a doctoral degree were relatively more likely to focus on clients' current presenting problems, whereas holders of masters degrees were more likely to focus on clients' families of origin. The overarching conclusion of this study, however, is that the influence of therapists' family background and personality traits on their therapeutic approach appears to be too complex and subtle to be easily categorized and measured.

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Rochat, Nadège. « Analyse énactive de l'activité en trail et ultra-trail : une approche multi-sourcing ». Thesis, Normandie, 2017. http://www.theses.fr/2017NORMR037/document.

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L’objectif de cette thèse était d’analyser l’activité en trail et ultra-trail en s’inscrivant dans le paradigme de l’énaction (Varela et al., 1993). Un observatoire multi-sourcing composé de discussions de forum, de récits de courses postés sur les blogs, d’entretiens énactifs et de données en troisième personne caractérisant les accélérations verticales du traileur et de son système de portage a été construit pour mener nos analyses. Les résultats des analyses des discussions de forums ont montré que les traileurs partagent des préoccupations relatives à l’entraînement et la santé. Les résultats des analyses des récits de blogs et des entretiens énactifs ont caractérisé l’activité des traileurs en situation de course, en reportant (a) des gestalts phénoménologiques dont l’agencement temporel a identifié des profils d’activité, (b) des états de vitalité dont la répartition et l’organisation temporelle différaient chez les finisheurs et les abandonneurs et (c) sept étapes-clés impliquées dans les abandons. Les résultats des analyses de l’usage du matériel ont montré que les sensations de ballotement du système de portage reportées par les traileurs étaient confirmées par les données comportementales. Pris dans leur ensemble, ces résultats suggèrent que l’activité des traileurs peut être caractérisée avec différentes sources de données, rendant compte des expériences signifiantes multiples énactés en situation. Ils fournissent des implications pratiques pour le champ de la psychologie du sport et transformatives pour les entreprises souhaitant intégrer les utilisateurs dans leur processus de conception
Rooted in the enaction paradigm (Varela et al., 1993), the aim of this thesis was to analyse the activity in trail and ultra-trail running. A multi-sourcing observatory was constructed to conduct our analyses. It was composed of forum discussions posted on the community website of the Raidlight brand, races narratives posted on blogs, enactive interviews and third-person data characterising the vertical oscillations of both the runners and their carrying systems. The results of the discussion forums showed that trail runners share common concerns regarding health and training issues. The results of the blog narratives and enactive interviews analyses characterised trail runners’ activity in race situation, by reporting (a) phenomenological gestalts, which temporal layout identified activity profiles, (b) vitality states, which repartition and temporal organisation differed in finishers and withdrawers and (c) seven key-stages involved in withdrawals. The results of analyses of the use of equipment showed that the sensations of bouncing reported by runners were confirmed by the behavioural data. Taken together, these results suggested that trail runners’ activity can be characterised by different data sources, reporting the various meaningful experiences that trail runners enact in situation. They provide practical and transformative implications for the proposition of an intervention model in sport psychology as well as a proposition of a multi-sourcing conception model for companies, which seek to integrate users in their conception processes

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Lowry, Matthew C. « A new approach to the train algorithm for distributed garbage collection ». Title page, table of contents and abstract only, 2004. http://hdl.handle.net/2440/37710.

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This thesis describes a new approach to achieving high quality distributed garbage collection using the Train Algorithm. This algorithm has been investigated for its ability to provide high quality collection in a variety of contexts, including persistent object systems and distributed object systems. Prior literature on the distributed Train Algorithm suggests that safe, complete, asynchronous, and scalable collection can be attained, however an approach that achieves this combination of behaviour has yet to emerge. The mechanisms and policies described in this thesis are unique in their ability to exploit the distributed Train Algorithm in a manner that displays all four desirable qualities. Further the mechanisms allow any number of mutator and collector threads to operate concurrently within a site; this is also a unique property amongst train-based mechanisms (distributed or otherwise). Confidence in the quality of the approach promoted in this thesis is obtained via a top-down approach. Firstly a concise behavioural model is introduced to capture fundamental requirements for safe and complete behaviour from train-based collection mechanisms. The model abstracts over the techniques previously introduced under the banner of the Train Algorithm. It serves as a self- contained template for correct train-based collection that is independent of a target object system for deployment of the algorithm. Secondly a means to instantiate the model in a distributed object system is described. The instantiation includes well-established techniques from prior literature, and via the model these are correctly refined and reorganised with new techniques to achieve asynchrony, scalability, and support for concurrency. The result is a flexible approach that allows a distributed system to exhibit a variety of local collection mechanisms and policies, while ensuring their interaction is safe, complete, asynchronous, and scalable regardless of the local choices made by each site. Additional confidence in the properties of the new approach is obtained from implementation within a distributed object system simulation. The implementation provides some insight into the practical issues that arise through the combination of distribution, concurrent execution within sites, and train-based collection. Executions of the simulation system are used to verify that safe collection is observed at all times, and obtain evidence that asynchrony, scalability, and concurrency can be observed in practice.
Thesis (Ph.D.)--School of Computer Science, 2004.

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Törnquist, Daun Klara, et Carl-Fredrik Vezzoli. « Optimisation of a Commuter Train System’s Energy Consumption : : A Statistical Approach ». Thesis, Umeå universitet, Institutionen för matematik och matematisk statistik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184732.

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In recent years the number of passengers travelling by train have increased and so has the requirements for punctuality and energy efficiency. The performance of the requirements depends on how the driver operates the train which in turn depends on the drivers skills and experiences. A Driver Advisory System(DAS) that gives the drivers guiding can increase the operational performance on these requirements. The aim of this thesis project was to investigate if the available data partly containing information about the trains velocity, acceleration and effect usage can be used to develop a system that aids the train drivers to reach the next station in time whilst minimising the consumed energy. The project was di-vided into two parts. In the first part different regression models and data setups were tested to see how well they could capture the effect usage. The tested regression techniques were linear regression and support vector regression, both techniques giving a good result with aR2over0.9. From the tried data setups the results shows that one estimated model could be used for all the trips in the system and the trips could be looked at as 1 or 3 phases. The second part of the project was to see if the estimated regression model could be used in an optimisation problem to find the best speed curve between two sta-tions. The results from the optimisation problem presents a solution between two stations with a lower energy consumption than the average historical trip. The optimisation results gives directives for the optimal way of driving the train as well, where the acceleration should not be over 0.85m/s^2 and where the max speed during a trip should not be higher than needed.

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