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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Physiologie de l’exercice et métabolomique chez des athlètes exposés à une altitude modérée aiguë / Physiology of Exercise and Metabolism in Athletes Exposed to Moderate Acute Altitude

Messier, Florian 21 December 2017 (has links)
A l’heure actuelle aucun consensus n’existe sur l’utilisation des substrats énergétiques lors d’un exercice en altitude. Certaines études ont montré une utilisation accrue des glucides en altitude comparée à la plaine mais les intensités d’exercices utilisées sont discutables et l’utilisation de méthodes biochimiques traditionnelles ont permis de doser qu’un nombre restreint de molécules. Aujourd’hui grâce à la métabolomique, il est possible d’analyser les variations d’un grand nombre de métabolites simultanément. Le but de cette thèse est d’étudier l’incidence de l’altitude modérée sur l’utilisation des substrats énergétiques à l’effort à l’aide de la métabolomique par résonnance magnétique nucléaire du proton. Des échantillons de plasmas et d’urines ont été collectés lors d’exercices d’endurance en plaine et en altitude modérée chez des sujets non acclimatés. Nos premiers résultats, dans les plasmas, ont montré une baisse de la glycémie et une utilisation accrue des acides aminés ramifiés entre avant et après un exercice d’endurance en altitude, ce qui n’a pas été observé en plaine. Ces résultats ont ensuite été confirmé lors d’un exercice d’endurance jusqu’à épuisement. De plus, nous avons montré que l’utilisation des urines permet de mettre en avant les résultats obtenus dans les plasmas, ce qui est très encourageant pour la compréhension des adaptations métaboliques en altitude par des méthodes non invasives. Pour finir, nous avons utilisé une méthode statistique innovante appelée « analyse en composantes communes et poids spécifiques ». Les résultats ont permis d’observer les variabilités communes entre les paramètres physiologiques mesurés et les variations des métabolites plasmatiques. / Although it is known that altitude impairs performance in endurance sports, there is no consensus on the involvement of energy substrates in this process. Some studies have shown an increased use of carbohydrates at altitude compared at plain but the intensities of exercises used are debatable and the use of traditional biochemical methods allowed to dose only a limited number of molecules. Today, thanks to metabolomics, it is possible to analyze the variations of a large number of metabolites simultaneously. The aim of this thesis is to investigate the incidence of moderate altitude on the use of energy substrates on stress using proton nuclear magnetic resonance metabolomics. Plasma and urine samples were collected during endurance exercises at plain and at moderate altitude in non-acclimatized subjects. Our first results in plasma showed decreased blood glucose and increased use of branched amino acids between before and after endurance exercise at altitude, which was not observed at plain. These results were then confirmed during an endurance exercise until exhaustion. Moreover, we have shown that the use of urine allows to highlight the results obtained in the plasmas, which is very encouraging for the understanding of the metabolic adaptations at altitude by noninvasive methods. Finally, we used an innovative statistical method called “ common components and specific weights analysis”. The results allowed us to observe the common variability between the measured physiological parameters and the variations of the plasma metabolites.
152

A influência de fatores ambientais na riqueza e composição da micota liquenizada em área de brejo de altitude e caatinga

Silva, Jeanne dos Reis 20 February 2015 (has links)
Lichens are the result of an symbiotic interaction between fungus, the mycobiont, and one or more photosynthetic components, the photobionts, which can be a green algae and/or a cyanobacteria. This study aimed to compare the species richness and composition of corticolous crustose lichens in two forest types, Caatinga and Brejo de Altitude, in relation to the influence of biotic and abiotic parameters such as light, bark pH and diameter at breast height (DBH) of the host, and elevation. To collect the lichens two transects of 300 m each were delimited, one per site. Along these transects, sampling points were marked every 10 m, in a total of 30 points per site and 60 points for the whole work. For each of the points, the nearest tree was selected which had a lichen cover at the height of 0.5 m to 1.50 m from the ground on the tree trunk. The species richness and composition for each area were analyzed. Altogether, 576 samples were collected, totaling 96 species of corticolous microlichens. There was no significant difference in species richness between the two areas. With respect to the species composition, the areas were different, but with some common species between them. Comparing the species richness of corticicolous lichens with biotic and abiotic factors, only the diameter at breast height (DBH) of the selected host presented a significant relationship. Relating the composition and biotic and abiotic factors, we had elevation, DBH and vegetation types, canopy openness, influencing the species composition. Thus, the results presented in this study are intended to contribute to the ecological knowledge of lichenized fungi, and enhancing the ecological and lichenological knowledge on Caatinga and Brejo de Altitude. / Os liquens surgem a partir da interação simbiótica entre um fungo, o micobionte, e um ou mais componentes fotossintéticos, fotobiontes, que podem ser algas verdes e, ou cianobactérias. Este trabalho teve como objetivo comparar a riqueza e composição de liquens corticícolas crostosos em duas fitofisionomias, Caatinga e Brejo de Altitude, no semiárido brasileiro, verificando se a riqueza e composição de espécies destes liquens são influenciadas pelos fatores bióticos e abióticos, como luminosidade, pH da casca e diâmetro na altura do peito (DAP) do hospedeiro, e altitude. Para a coleta dos liquens, foram demarcados dois transectos de 300 m, um em cada área de estudo. Ao longo destes transectos foram demarcados pontos a cada 10 m, sendo 30 pontos para cada área, perfazendo um total de 60 pontos. Para cada ponto demarcado, foram adotados como critério de escolha do hospedeiro a maior proximidade do ponto e a presença de talos liquênicos na altura de 0,5 m até 1,50 m em relação ao solo no tronco da árvore. Foram analisadas a riqueza e composição de espécies para cada área. Ao todo, foram coletadas 576 amostras, totalizando 96 espécies de microliquens corticícolas. Não houve uma diferença significativa na riqueza entre as duas áreas. Com relação à composição de espécies, as áreas apresentaram diferença, porém com algumas espécies comuns para as duas áreas. Comparando a riqueza de liquens corticícolas com os fatores bióticos e abióticos, apenas o diâmetro à altura do peito (DAP) do hospedeiro selecionado, apresentou-se de forma significativa em relação à riqueza de espécies de liquens corticícolas. Relacionando a composição de espécies e os fatores bióticos e abióticos, tivemos elevação, DAP e fitofisionomias (local), abertura do dossel, e riqueza influenciando a composição. Desta forma, os resultados apresentados neste estudo visam contribuir para o conhecimento ecológico dos fungos liquenizados, assim como se torna subsídio para outras pesquisas que venham a aprimorar e enriquecer o conhecimento ecológico e liquenológico da Caatinga e Brejos de Altitude.
153

Composição florística, similaridade e influência de variáveis ambientais de uma floresta de araucária na Serra da Mantiqueira, Minas Gerais, Brasil / Floristic composition, similarity and influence of environmental variables in the Araucaria Forest in the Serra da Mantiqueira, Minas Gerais, Brazil

Santiago, Daniel Silva 28 March 2014 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-11T14:10:18Z No. of bitstreams: 1 danielsilvasantiago.pdf: 1973450 bytes, checksum: 649b65ee91ba9b6f134c21d3f9fc8783 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-02-26T12:02:22Z (GMT) No. of bitstreams: 1 danielsilvasantiago.pdf: 1973450 bytes, checksum: 649b65ee91ba9b6f134c21d3f9fc8783 (MD5) / Made available in DSpace on 2016-02-26T12:02:22Z (GMT). No. of bitstreams: 1 danielsilvasantiago.pdf: 1973450 bytes, checksum: 649b65ee91ba9b6f134c21d3f9fc8783 (MD5) Previous issue date: 2014-03-28 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O estado de Minas Gerais apresenta uma cobertura vegetal rica e diversa, especialmente nas áreas de elevadas altitudes, que apresentam um refúgio para a flora. O Parque Estadual da Serra do Papagaio (PESP), localizado na Serra da Mantiqueira, abriga um dos raros fragmentos de floresta mista lati-aciculifoliada (FML) do estado e está inserido em um mosaico vegetacional composto por campinas nebulares e florestas latifoliadas nebulares. Os objetivos deste trabalho foram analisar os aspectos florísticos, a similaridade e a influência das variáveis ambientais da FML do PESP. Foram realizadas coletas mensais (de Março de 2012 a Junho de 2013) de exemplares férteis (excluindo-se as epífitas) nas áreas de FML aluvial e de encosta do PESP, com altitudes entre 1.650 e 2.000 m. A partir do banco de dados TreeAtlan, foram obtidas informações de 51 localidades acima de 800 m de altitude na Serra da Mantiqueira, utilizadas para as Análises de Similaridade, e relação com as variáveis ambientais (Análise de Correspondência Canônica, CCA) do estrato arbustivo/arbóreo. Foram registradas 312 espécies distribuídas em 163 gêneros e 83 famílias de plantas vasculares, sendo 292 angiospermas, duas gimnospermas e 18 pteridófitas. As famílias com maior riqueza foram Asteraceae (49 spp.), Melastomataceae (33 spp.), Rubiaceae (16 spp.), Solanaceae (15 spp.) e Myrtaceae (13 spp.). Os gêneros mais ricos foram: Leandra (14 spp.), Solanum (11 spp.), Baccharis (9 spp.), Myrcia e Tibouchina (8 spp. cada). Foram encontradas duas espécies ameaçadas de extinção e seis novas ocorrências para o estado de Minas Gerais. Além das espécies características de clima temperado, observou-se a presença de espécies frequentes em florestas montanas e altomontanas da Região Sudeste do Brasil e nos Andes, destacando a altitude como fator determinante na composição florística. A CCA apontou maior correlação da FML com a precipitação no inverno e com a altitude. A análise de similaridade apontou maior semelhança com as nanoflorestas latifoliadas da Serra Fina, Serra Negra (Minas Gerais) e Agulhas Negras (Rio de Janeiro), provavelmente associada ao compartilhamento de espécies de altitudes elevadas e a proximidade geográfica entre as áreas, indicando que a FML do PESP recebe influência da flora local e não apresenta o padrão florístico das outras FML da Serra da Mantiqueira. / Minas Gerais state has a rich and diverse plant cover, especially in high altitude locations which are like refuges for the regional flora. The Parque Estadual da Serra do Papagaio (PESP), located in the Mantiqueira hill range, houses one of the rare fragments of Mixed Needle-broadleaved Forest (MNF) of the state, and is inserted into a mosaic of high-altitude grasslands and dense forests. This study aims at analyzing the floristic composition, similarity and the influence of environmental variables in the MNF of PESP. Monthly expeditions were done (March 2012 to June 2013) and all fertile plants (excluding epiphytes) were collected in alluvial and slope MNF areas at altitudes ranging from 1650-2000 m. We obtained, from the TreeAtlan database, information on 51 areas located above 800 m altitude in Serra da Mantiqueira, which were used in Similarity Analysis and Canonical Correspondence Analysis (CCA) of shrub/tree components. A total of 312 species was recorded, distributed to163 genera and 83 families, 292 of which were angiosperms, two gymnosperms and 18 pteridophytes. The richest families were Asteraceae (49 spp.), Melastomataceae (33 spp.), Rubiaceae (16 spp.), Solanaceae (15 spp.) and Myrtaceae (13 spp.). The richest genera were Leandra (14 spp.), Solanum (11 spp.), Baccharis (9 spp.), Myrcia (8 spp.) and Tibouchina (8 spp.). We also found two threatened species and six new records for Minas Gerais state. We observed the presence of temperate climate species that are also frequent in others montane and upper montane forests in Southeastern Brazil and in the Andes, stressing altitude as an important factor in floristic composition. The CCA showed a higher correlation with the winter precipitation and with altitude. The similarity analysis showed a greater resemblance to Broadleaved dwarf-forest from Serra Fina, Serra Negra and Agulhas Negras, probably associated with shared high altitude species and geographical proximity among these areas, indicating that the MNF of PESP receives influences of the local flora and not presents the floristic pattern of other MNF in the Mantiqueira hill range.
154

Flora da Serra da Pedra Branca, Caldas, Minas Gerais, Brasil

Rezende, Munike Gonçalves de 19 May 2010 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-07-04T10:43:34Z No. of bitstreams: 1 munikegoncalvesderezende.pdf: 393903 bytes, checksum: 0462010120ab29a1f4bf0857d5ceec79 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-08T13:05:04Z (GMT) No. of bitstreams: 1 munikegoncalvesderezende.pdf: 393903 bytes, checksum: 0462010120ab29a1f4bf0857d5ceec79 (MD5) / Made available in DSpace on 2017-08-08T13:05:04Z (GMT). No. of bitstreams: 1 munikegoncalvesderezende.pdf: 393903 bytes, checksum: 0462010120ab29a1f4bf0857d5ceec79 (MD5) Previous issue date: 2010-05-19 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / A Serra da Pedra Branca localiza-se no sudoeste do estado de Minas Gerais, no município de Caldas (21° 58' - 55' S e 46° 24' -22' W). É uma feição marcante no relevo, inserida no Bioma Mata Atlântica e considerada área prioritária para a conservação da flora no estado de Minas Gerais. Os objetivos do presente estudo foram realizar o levantamento florístico da Serra da Pedra Branca com ênfase na vegetação dos Campos de Altitude, comparar a flora da Serra da Pedra Branca à coletada por Anders Fredrik Regnell no século XIX em Caldas e analisar a similaridade florística entre áreas de afloramentos rochosos. Para tal, foram realizadas expedições mensais de coleta no período de março de 2008 a fevereiro de 2009. O levantamento florístico registrou 340 espécies de plantas vasculares sendo 46 identificadas apenas até nível de gênero. Destacam-se as seguintes famílias quanto à riqueza de espécies entre as angiospermas: Orchidaceae (27 spp.), Asteraceae e Rubiaceae (16 spp. cada), Fabaceae e Piperaceae (15 spp. cada), Bromeliaceae (14 spp.), Solanaceae (10 spp) e Poaceae (nove spp.) e, entre as pteridófitas: Polypodiaceae (15 spp.) e Aspleniaceae (oito spp.). As espécies herbáceas representam 56,5% da flora, seguida por arbóreas (21,8%), arbustivas (15,3%), lianas (5,9%) e arborescentes (0,6%). A comparação dos dados atuais da flora com a dos dados levantados por Anders Fredrik Regnell, indica a presença de 90 espécies em comum às duas listagens. De modo geral, a diversidade ao longo dos anos não diferiu apesar da riqueza dentro de algumas famílias ter sido diferente. A intensa degradação e supressão de vegetação ocorrida no município de Caldas ao longo dos anos para a abertura de pastagens, agricultura e mineração pode ter causado o desaparecimento de diversas espécies e o estabelecimento de outras. A análise de similaridade florística realizada entre a flora dos Campos de Altitude da Serra da Pedra Branca e outras áreas de afloramentos rochosos localizadas no sudeste de Minas Gerais e Rio de Janeiro revelou uma maior proximidade da Serra da Pedra Branca com áreas de Campos Rupestres o que pode ser explicado pela influência do cerrado na flora desses ambientes. A vegetação da Serra da Pedra Branca é considerada um ambiente em perigo já que a presença de espécies ameaçadas de extinção e/ou endêmicas, associada às condições ambientais locais com acelerado ritmo de destruição, evidenciam a necessidade de medidas urgentes de preservação da biodiversidade local. / Serra da Pedra Branca is located in the southwestern of Minas Gerais state, municipality of Caldas (21 ° 58 '- 55' S and 46 ° 24 '-22' W). Striking feature in the landscape, the region is part of the Atlantic Forest biome and is considered priority area for conservation the flora in Minas Gerais state. The aims of this paper were the elaboration of a floristic checklist of Serra da Pedra Branca with emphasis on the vegetation of Campos de Altitude, compare the flora of the Serra da Pedra Branca with the flora collected by Anders Fredrik Regnell in the nineteenth century in Caldas and analyse the floristic similarity between areas of rock outcrops. For that, monthly collections were made from March 2008 to February 2009. The floristic survey recorded 340 vascular plant species and 46 identified only up to genus level. The following families are important for their species richness among the angiosperms: Orchidaceae (27 spp.), Asteraceae and Rubiaceae (16 spp. each one), Piperaceae and Fabaceae (15 spp. each one), Bromeliaceae (14 spp.), Solanaceae (10 spp) and Poaceae (nine spp.), and among the ferns: Polypodiaceae (15 spp.) and Aspleniaceae (eight spp.). Herbs represent 56,5% of the flora, followed by trees (21,8%), shrubs (15,3%), climbers (5,9%) and arborescent (0,6%). Comparing the current floristic data with the data collected by Anders Fredrik Regnell in Caldas in the nineteenth century, indicates the presence of 90 species in common to both listings. In general, the diversity over the years did not differ despite the richness within some families have been quite different. The intense degradation and removal of vegetation occurred in the municipality of Caldas over the years to open pastures, agriculture and mining may have caused the disappearance of several species and the establishment of others. The analysis of floristic similarity between the flora of Campos de Altitude da Serra da Pedra Branca and other areas of rocky outcrops located in southeastern of Minas Gerais state and Rio de Janeiro, showed a greater proximity of the Serra da Pedra Branca with areas of Campos Rupestres which can be explained by the influence of the cerrado in the floristic of these environments. The vegetation of the Serra da Pedra Branca is considered an endangered environment since the presence of endangered species and / or endemic, associated with local environmental conditions with accelerated rate of destruction, highlight the need for urgent action to preserve local biodiversity.
155

Florística, influência altitudinal e aspectos ecológicos das samambaias ocorrentes na RPPN Pedra D’Antas (Lagoa dos Gatos, Pernambuco, Brasil)

LOPES, Amanda Sibele da Silva 28 February 2013 (has links)
Submitted by Rafael Santana (rafael.silvasantana@ufpe.br) on 2017-08-01T17:56:47Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação_-_Amanda_Lopes_-_PPGEO_-_2013.pdf: 3744924 bytes, checksum: 498108a19350d5eac53892be88dac508 (MD5) / Made available in DSpace on 2017-08-01T17:56:47Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação_-_Amanda_Lopes_-_PPGEO_-_2013.pdf: 3744924 bytes, checksum: 498108a19350d5eac53892be88dac508 (MD5) Previous issue date: 2013-02-28 / FACEPE / Este estudo teve como objetivo apresentar dados relacionados à florística, à influência altitudinal e aos aspectos ecológicos das samambaias na RPPN Pedra D´antas, localizada no município de Lagoa dos Gatos, Pernambuco, Brasil. Para a execução deste estudo, foram realizadas três excursões semanais (oito horas diárias), nas quais o fragmento foi explorado através de caminhadas, priorizando os habitats onde as samambaias ocorrem com maior frequência. Os processos de coleta, identificação e herborização do material seguiram a literatura especializada. Na RPPN Pedra D’Antas foram registradas 82 espécies de samambaias, distribuídas em 37 gêneros e 17 famílias, Pteridaceae (20 spp.), Polypodiaceae (15 spp.) e Dryopteridaceae (10 spp.), as mais representativas. Os gêneros com maior número de espécies foram Adiantum e Thelypteris, com 10 e sete espécies, respectivamente. A riqueza específica variou entre as faixas altitudinais, sendo maior na faixa entre 600-700 m com 63 espécies, e a menor representatividade foi registrada na faixa entre 400-500 m com 15 espécies. A variação altitudinal também ocasionou modificação na composição florística, principalmente entre a faixa 400-500 com as demais. Estes dados indicam uma riqueza de samambaias importante no contexto da Floresta Atlântica Nordestina, além de demonstrar a influência da altitude nos aspectos ecológicos destas plantas. / This paper aimed present data related to floristc survey, the altitudinal influence and ecological aspects of ferns in the RPPN Pedra D´Antas, located in the municipality of Lagoa dos Gatos, Pernambuco, Brazil. For the execution of this study, there were three excursions per week (eight hours) to field works, in which the fragment was explored prioritizing habitats where ferns occur with greater frequency. The processes of collecting, identifying and herborization material followed the literature. In RPPN Pedra D'Antas were recorded 82 species of ferns, belonging to 37 genera and 17 families, Pteridaceae (20 spp.), Polypodiaceae (15 spp.) and Dryopteridaceae (10 spp.) were the most representative. The richest genera were Adiantum and Thelypteris, with 10 and seven species, respectively. The richness varied between altitudinal zones, being higher in the range between 600-700 m with 63 species, and the lowest representation was recorded in the range of 400-500 m with 15 species. The altitudinal variation also resulted in changes in the floristic composition, especially between the 400-500 range with the other. These data indicate a richeness of ferns important in the context of the Northeastern Atlantic Forest, as well as demonstrating the influence of altitude on the ecological aspects of these plants.
156

Cafés da espécie Coffea arabica L. produzidos no Circuito das Águas Paulista: caracterização física, química e sensorial / Coffees of the Coffea arabica L. species produced in the Circuito das Águas Paulista: physical, chemical and sensory characterization

Cintia Maretto 29 August 2016 (has links)
Dentre as principais áreas produtoras de café no Brasil, destaca-se a região do Circuito das Águas Paulista - CAP. Devido às suas características edafoclimáticas, com clima ameno, temperaturas entre 13ºC e 26ºC e altitudes de até 1.400 m, a região, composta por nove municípios da Serra da Mantiqueira, apresenta potencial de produção de cafés especiais. Desse modo, o objetivo deste trabalho foi caracterizar os cafés de diferentes cultivares da espécie Coffea arabica L. produzidos em duas faixas de altitude da região do CAP a partir de entrevistas semiestruturadas com os cafeicultores e análises físicas, químicas e sensoriais. O delineamento experimental foi inteiramente casualizado, baseado na interação entre ambiente (duas faixas de altitude - abaixo e acima de 1.100 m) e genótipos (Catucaí Amarelo, Catuaí Vermelho, Obatã, Mundo Novo, Bourbon Amarelo, Icatu Amarelo e Iapar). Os resultados foram submetidos à ANOVA (teste F) e ao teste de Tukey (p<0,05) (análises químicas e sensoriais). Em adição, os dados das sensoriais (SCAA e ADQ) foram submetidos às Análises de Agrupamento Aglomerativo Hierárquico e de Componentes Principais, sendo a análise de frequência das citações da ADQ submetida também ao Teste de Cochran. Foram encontradas diferenças significativas (p<0,05) entre as amostras para todas as análises. Dentre as amostras estudadas, cinco foram classificadas como \"especiais\" (SCAA), com pontuação de até 84,42 e todas foram classificadas como Gourmet (ADQ), com destaque para os atributos: floral/frutado, acidez, doçura e corpo pronunciados, e sabor de nozes/avelã, evidenciando as características singulares dos cafés do CAP. Quanto às cultivares, as amostras de Obatã apresentaram as maiores notas (alta qualidade); as de Mundo Novo, notas intermediárias, com aroma da bebida pronunciado e menor adstringência; e as de Bourbon Amarelo, menores notas. Quanto à altitude, houve influência na acidez, pois parte das amostras cultivadas abaixo de 1.100 metros apresentou valores mais altos desse atributo, todavia, sem interferência negativa comprovada na qualidade final da bebida. Além disso, também influenciou a cafeína, pois as amostras de Catucaí Amarelo, Catuaí Vermelho, Obatã e Bourbon Amarelo cultivadas abaixo de 1.100 metros apresentaram valores superiores. A cultivar Bourbon Amarelo apresentou maiores teores de ácidos clorogênicos e, as amostras preparadas pela via úmida, maiores teores de trigonelina, cafeína e ácidos clorogênicos (Catucaí Amarelo e Obatã) em relação às de via seca, além de notas mais altas ou intermediárias na análise sensorial (exceto a de Bourbon Amarelo). Em suma, a região do CAP possui potencial para produção de cafés especiais, de características singulares, que envolvem tradição, história, cultura e aspectos ambientais. Contudo, podem ter ocorrido interferências no processo produtivo de algumas das amostras analisadas no presente estudo. / Among the main coffee producing areas in Brazil, there is the Circuito das Águas Paulista - CAP. Due to its soil and climate characteristics, temperatures between 13°C and 26°C and altitudes up to 1,400 m, the region consists of nine districts of the \"Serra da Mantiqueira\" and has great potential for producing high quality coffee. Thus, the objective of this study was to characterize the coffees of different cultivars of Coffea arabica L. produced in two altitude ranges of the CAP region from semi-structured interviews with farmers and physical, chemical and sensory analysis. The experimental design was completely randomized, based on the interaction between environment (two altitude ranges - below and above 1,100 m) and genetic (cultivars: Yellow Catucaí, Red Catuaí, Obatã, Mundo Novo, Yellow Bourbon, Yellow Icatu and Iapar). The results were submitted to ANOVA (F test) and Tukey test (p <0.05) (chemical and sensory analysis). In addition, the sensory data (SCAA and ADQ) were subjected to Hierarchical agglomerative clustering and Principal component analysis, and the analysis of frequency of ADQ quotes were submitted also to Cochran test. There were significant differences (p <0.05) between samples for all analyzes. Among the samples analyzed, five were classified as \"special\" (SCAA), with scores of up to 84.42 and all were classified as Gourmet (ADQ), highlighting the attributes: floral / fruity, acidity, sweetness and body pronounced, and nutty / hazelnut, highlighting the unique features of the CAP coffees. As for the cultivars, Obatã samples showed the highest scores (high quality); the Mundo Novo, intermediate notes, with the aroma pronounced and less astringency drink; and Yellow Bourbon, smaller notes. As for the altitude, there was influence on acidity, because of the samples grown below 1,100 m showed higher values of this attribute, however without negative interference proven in the final quality of the drink. In addition, it also influenced the caffeine, because the samples Yellow Catucaí, Red Catuaí, Obatã and Yellow Bourbon grown below 1,100 m showed higher values. The Yellow Bourbon showed higher levels of chlorogenic acids and the samples prepared by the wet method, higher trigoneline content, caffeine and chlorogenic acids (Yellow Catucaí and Obatã) in relation to dry ones, and higher and intermediate grades in analysis sensory (except for the Yellow Bourbon). In short, the CAP region has potential for production of specialty coffees, with unique characteristics, involving tradition, history, culture and environmental aspects. However, interference may have occurred in the production process of some of the samples analyzed in this study.
157

PHYSIOLOGICAL RESPONSES TO SINGLE AND DOUBLE LEG CYCLING IN NORMOXIC AND HYPOXIC CONDITIONS

Draper, Shane N. 02 May 2018 (has links)
No description available.
158

A high-altitude nuclear environment simulation

White, Ryan D. January 1900 (has links)
Master of Science / Department of Mechanical and Nuclear Engineering / J. Kenneth Shultis / A program which calculates the radiation dosage to a predetermined set of components inside of a kill vehicle as a result of natural or artificial radiation sources has been developed for use within the confines of a parent external simulation. This dose can then be used to determine if a critical component has malfunctioned or failed completely, thereby rendering the interceptor unable to finish its mission. Knowledge of system and component performance as a function of incident high-energy particles leads to better battle management planning, CONOPS, and potentially a more efficient shielding design to achieve a higher probability of mission success.
159

Caractérisation, modélisation et validation du transfert radiatif d'atmosphères non standard : impact sur les corrections atmosphériques d'images de télédétection

Zidane, Shems January 2012 (has links)
Cette étude est basée sur des données multi-altitudes aéroportées acquises en juillet 2004 lors d'un événement atmosphérique inhabituel dans la région de Saint-Jean-sur-Richelieu. Nous entendons en cela une atmosphère dont la distribution des aérosols ne respecte pas les variations habituellement implémentée dans les codes de transfert radiatifs. Les surfaces au sol imagées pendant cette campagne de terrain couvraient une variété spectrale assez diversifiée, à savoir des surfaces agricoles, des plans d'eau et des zones urbaines et forestières. L'aspect multi-altitude de cette acquisition de données a permis de caractériser les mêmes cibles au sol avec des contributions de l'atmosphère variant en fonction de l'altitude considérée afin de caractériser au mieux la perturbation observée durant cette campagne et de permettre une meilleure caractérisation de la perturbation apportée par une variation non-standard (panache de fumée). La transformation de la luminance apparente aux trois altitudes en réflectance apparente et l'implémentation de la perturbation apportée par le panache de fumée dans un modèle classique a permis une correction atmosphérique appliquée aux deux altitudes les plus hautes. Les résultats ont démontré une cohérence avec les réflectances apparentes de validation qui confirmait la véracité de notre modélisation du cas non-standard. Ces résultats ont d'autant plus étés pertinent [i.e. pertinents] pour la plus haute altitude de 3,17km : la réflectance apparente à cette altitude est au dessus de la majeur [i.e. majeure] partie du panache de fumée et intègre une bonne proportion de la perturbation apportée par ce panache, ce qui représente un test probant de notre capacité à corriger adéquatement l'influence de cette perturbation. Les perturbations atmosphériques standard sont évidemment prises en compte dans la majorité des modèles atmosphériques, mais ceux-ci sont souvent basés sur des variations monotones des caractéristiques physiques de l'atmosphère avec l'altitude. Lorsque la radiation atmosphérique est perturbée, par un panache de fumée ou un événement de pollution atmosphérique local et non standard, cela nécessite une modélisation et une modification adéquate des modèles existants en fonction des paramètres que l'on pourra obtenir sur ladite perturbation. Les intrants principaux de cette étude étaient ceux normalement utilisés lors d'une correction atmosphérique classique à savoir les luminances apparentes mesurées par un imageur aéroporté mais à trois altitudes différentes et l'épaisseur optique des aérosols (AOD) qui était acquise depuis le sol. La méthodologie que nous avons employé [i.e. employée] utilise aussi un code de transfert radiatif (CAM5S, pour Canadian Modified 5S, qui vient directement du code de transfert radiatif 5S dans le visible et proche infrarouge). Cependant il nous faudra aussi avoir recours à d'autres paramètres et données afin de modéliser correctement la situation atmosphérique particulière présente sur les images multi-altitude acquises pendant la campagne de terrain à Saint-Jean-sur-Richelieu. Nous avons alors élaboré un protocole de modélisation de perturbation atmosphérique non standard où une gamme de données auxiliaires disponibles est venue compléter nos données principales. Cela a permis l'élaboration d'une méthodologie robuste et relativement simple adaptée à notre problématique. Ces données auxiliaires, à savoir des données météorologiques, des profils LEDAR, différentes images satellites et des données de photomètres solaires qui ont permis la détermination de la fonction de phase des aérosols, ont été suffisantes pour établir une modélisation adéquate du panache de fumée observé en terme de distribution verticale non monotone des paramètres physiques relevés lors de cette campagne. Cette distribution non-standard à été par la suite interprétée en terme de profil spécifique de l'AOD qui a remplacé les profils des AOD employés dans le modèle de correction atmosphérique CAM5S. En fonction de cette modélisation, nous montrons que l'erreur entre les réflectances apparentes au sol obtenu [i.e. obtenue] par le processus de correction atmosphérique et les réflectances apparentes au sol provenant du processus de validation dR*(0), moyenné quadratiquement à travers les bandes visibles, reste majoritairement dans une gamme inférieure à 0,01 d'erreur quadratique moyenne des R*(0) après avoir modélisé la perturbation non-standard, ce qui permet une estimation plus acceptable des réflectances multi-altitude et du biais existant entre la prise en compte et la non prise en compte de cette perturbation dans le modèle atmosphérique. D'importants écarts ont néanmoins été observés, majoritairement attribuables à la difficulté apportée par les conditions d'acquisition, les grandes disparités observées entre l'échantillonnage des mêmes surfaces aux trois altitudes, et probablement des erreurs de modélisation et/ou de calibration. La nécessité d'améliorer le processus d'acquisition, de modélisation et de prévision de telle perturbation est largement décrit dans ce document afin de permettre à l'avenir d'établir un protocole d'acquisition plus adapté grâce notamment à une surveillance et un suivi des perturbations atmosphériques maintenant possible grâce aux outils décrits. L'originalité de cette étude réside dans une nouvelle approche de la caractérisation de ces perturbations atmosphériques par l'incorporation d'une structure non standard dans un modèle de correction atmosphérique opérationnel et de démontrer que cette approche présente des améliorations significatives des résultats par rapport à une approche qui ignore la perturbation du profil vertical standard tout en utilisant des valeurs d'AOD totaux correctement mesurés. Le modèle de profil que nous avons employé était simple et robuste, mais a capturé suffisamment de caractéristiques du panache pour réaliser des améliorations significatives en termes de précision de correction atmosphérique. Le processus global d'aborder tous les problèmes rencontrés dans l'analyse de notre perturbation des aérosols nous a aidé à construire une méthodologie appropriée pour caractériser ces événements sur la base de la disponibilité des données, distribué gratuitement et accessibles à la communauté scientifique. Cela rend cette étude adaptable et exportable à d'autres problématiques du même genre.
160

Determinants and correlates of intra-individual variability in reaction time

Dykiert, Dominika January 2011 (has links)
Traditionally, reaction time (RT) was conceived of as an average speed of a number of responses made by an individual, or mean RT. Increasingly, however, intraindividual variability in reaction time (RT IIV) – the consistency of responses by a single person across trials – is used as an additional or even alternative measure. RT IIV is often found to be elevated in a number of conditions that affect the central nervous system functioning, such as traumatic brain injury or neurodegenerative diseases. It can predict change in cognitive performance in ageing, progression from normal ageing to mild cognitive impairment, and even death. Therefore, RT IIV may be of great practical importance. However, RT IIV and mean RT are correlated; therefore it is often problematic to draw conclusions about unique associations between these and other variables. One objective of the work presented in this thesis was to investigate determinants and correlates of simple and choice RT IIV and to test which associations may be accounted for by the individual differences in mean RT. The first investigation was concerned with age differences in RT IIV. Following a systematic review of literature, a series of meta-analyses demonstrated that older individuals (aged 60 years and above) have greater RT IIV than young or middle-aged adults in simple and choice RT tasks. The effects were reduced but still significant when RT IIV was adjusted for mean RT. The next study was a cross-sectional investigation of the associations between age and RT IIV, as well as of sex differences in RT IIV, across the lifespan in participants ranging in age from 4 to 75. Non-linear effects of age were found for RT IIV measures, such that variability decreased with age in children and increased with age in older adults. A novel finding from this study was that sex differences in RT IIV were present among adults but not children, suggesting that there might be an age threshold at which sexes diverge in their RT IIV trajectories. The results also indicated that findings regarding RT IIV may differ depending on the variability measure used (that is, whether and how mean RT is controlled). The second study on the same sample investigated variability on a trial-by-trial basis. Specifically, it tested the hypothesis that sex differences in variability are due to females being disproportionately slower at the first trial which inflates their overall RT IIV. This hypothesis was not supported. Another investigation used longitudinal data from the West of Scotland Twenty-07 study. Three cohorts of individuals aged approximately 15, 35 and 55, were followed up for 20 years and had RT data collected at four occasions. Analyses confirmed non-linear effects of age on RT IIV found in the earlier cross-sectional investigation. The final study investigated the effect of high altitude on RT IIV. It found that altitude-related increase in RT IIV is fully accounted for by general slowing of RT at high altitude. The overall pattern of results obtained from the investigations suggests that RT IIV increases with age in adults and that not all of the increase is due to general slowing. Moreover, the results show that sex differences in RT IIV are not uniform across the lifespan. Finally, whereas associations of RT IIV with some variables, for example age, are relatively robust to controlling for mean RT, others are fully attenuated by such practice.

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