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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.
551

ANÁLISE DA PERCEPÇÃO DAS CONDIÇÕES DE TRABALHO, AMBIENTE E SAÚDE DOS MOTORISTAS DE CAMINHÃO EM RIO VERDE-GO

Ribeiro, Fábio Henrique 24 September 2008 (has links)
Made available in DSpace on 2016-08-10T10:55:37Z (GMT). No. of bitstreams: 1 Fabio Henrique Ribeiro.pdf: 1472181 bytes, checksum: 70e834664a56ef82dbf61398ecb51b4b (MD5) Previous issue date: 2008-09-24 / This work analyses the perception of the professional driver about his work conditions, environment and health. The objective was to identify the difficulties met by the professional driver in the exercise of the profession, to verify his labor and health conditions, his perception of environmental changes and the kind of support received on the highways of the state of Goiás. It is a descriptive and exploratory study that uses a questionnaire (N=83) with questions about sociodemographic and anthropometrics characteristics; labor performance; self health evaluation; work related environment; general well-being using a scale developed by Fazio (1971) and used by Lima Paula e Torres (2001). The data on the accidents occurred between 2006 and 2007 in Goiás federal highways was obtained from the PRF-GO database. Within that period, 872 motorway accidents were registered, most involving males. In a total of 456 deaths, 256 were the drivers. The majority of accidents involved small vehicles, followed by tractor trucks and trucks. The average age of the participants was 42,8 years old, all male. The anthropometrics profile provided by corporal mass index (CMI) was 26,19 kg/m² of which 51,6% was overweight and 12% obese. On the level of school education, the predominance was incomplete elementary education with 39,8%. Most participants were married, with an average family income between R$1,501.00 and R$2.000,00, and 72% of the families depended solely on the participants income. Out of 83 interviews, 75,9% had a type E professional driver s license, and 26,5% owned the vehicle. The average professional time was 13,8 years. The well-being scale presented an average of 3,2 (DP=0,8), which indicates physical and psychological well-being bellow of medium point of the scale (4). Approximately 63% do not take regular medical examination. On average, 43,4% had medical exams over 2 years ago, 19% said that they suffer from some illness. On the perception of the environment, 71% have noticed environmental degradation. The results of research allows to conclude that the job of truck driver demands great ability of the worker, but the conditions where it is performed imposes physical and psychological demands that interfere with professional performance and road safety. / O presente trabalho trata da análise da percepção do motorista profissional sobre suas condições de trabalho, ambiente e saúde. O objetivo do trabalho foi conhecer as dificuldades encontradas pelo motorista de trânsito rodoviário no exercício de sua profissão, verificar suas condições de trabalho e saúde, sua percepção em relação às mudanças ambientais, bem como o tipo de apoio que recebe nas rodovias de Goiás. Trata-se de um estudo descritivo e exploratório que utilizou como instrumento um questionário (N=83) contendo perguntas sobre características sócio-demográficas e antropométricas, desempenho laboral; autoavaliação sobre a saúde; meio ambiente relacionado ao trabalho; escala do bemestar geral, desenvolvida por Fazio (1971) e utilizada por Lima Paula e Torres (2001). O levantamento de acidentes ocorridos entre os anos de 2006 e 2007 em rodovias federais de Goiás, foi obtido do banco de dados informatizado da PRFGO. Neste período, ocorreram 872 acidentes terrestres, com maioria de envolvidos sendo do sexo masculino. Em um total de 456 óbitos, 256 foram condutores dos veículos. O maior índice de acidentes ocorreu com automóveis, seguido de caminhão trator e caminhão. A média da idade dos participantes da pesquisa foi de 42,8 anos, todos do sexo masculino. O perfil antropométrico dado pelo índice de massa corpórea (IMC) foi de 26,19kg/m² onde 51,6% estavam acima do peso e 12% obesos. Quanto ao grau de escolaridade, a predominância foi o ensino fundamental incompleto, com 39,8%. Em relação ao estado civil, há predominância de casados. A renda familiar está entre R$1.501,00 e R$2.000,00 e 72% das famílias dos participantes depende exclusivamente de seu trabalho. Dos 83 entrevistados, 75,9% possuíam a CNH categoria profissional E e 26,5% eram donos do veículo. Quanto ao tempo de trabalho, a média apurada foi de 13,8 anos. A escala de bem-estar apresentou média de 3,2 (DP= 0,8), indicando o bem-estar físico e psicológico, abaixo do ponto médio da escala (4). Aproximadamente 63% responderam que não fazem regularmente exames de saúde, e em média, 43,4% realizaram há mais de dois anos o último exame de saúde, 19% alegaram ter alguma doença. Sobre a percepção do meio ambiente, 71% dos profissionais notaram a degradação ambiental. Os resultados da pesquisa permitem concluir que a profissão motorista de caminhão exige grande competência do trabalhador, e as condições em que ela é exercida provocam desgaste físico e psicológico que interferem na atuação do profissional e na segurança nas estradas.
552

A Terra como um exoplaneta / Earth as exoplanet

Luander Bernardes 29 November 2018 (has links)
É notório o fato de que o interesse pela detecção de vida fora da Terra tenha aumentado no mundo científico. A existência de possíveis traçadores biológicos na atmosfera terrestre, a presença de material vivo ou de material orgânico decomposto em superfícies e no mar aumentam as possibilidades de sucesso das pesquisas. A vida na Terra é encontrada em todas as partes, e o planeta está saturado de suas manifestações. O objetivo da presente tese é o desenvolvimento de uma metodologia que ofereça ideias para a detecção de bioassinaturas fora da Terra, particularmente em exoplanetas. Em termos de biologia molecular, a principal assinatura de vida é o DNA (ácido desoxirribonucleico), que organiza e sedia o código genético de todos os seres vivos. Outras moléculas que denunciam a presença de vida são a clorofila, carotenoides, fragmentos de DNA, moléculas orgânicas, etc. Na tentativa de se encontrar bioassinaturas na atmosfera de exoplanetas, um requisito deve ser atendido: a identificação de bandas características que permitam a detecção de um sinal que esteja associado a uma biomolécula complexa, preferencialmente na região do infravermelho, vista em meio aos picos de gases atmosféricos. Sendo assim, uma série de análises espectrais foram realizadas para amostras de DNA/células do micro-organismo extremófilo Halobacterium salinarum, com a finalidade de serem comparadas ao espectro infravermelho, obtido de forma direta da atmosfera terrestre. A pesquisa por marcadores específicos foi realizada a fim de determinar os picos que permitam a detecção desses componentes singulares quando suspensos em gases atmosféricos. Os resultados da pesquisa mostram que a atmosfera terrestre está contaminada com moléculas complexas. Existem 37 absorções em comum quando se compara o espectro da atmosfera terrestre com os espectros de células ou DNA (por exemplo 966, 936, 924, 886 e 866 cm-1). Entre elas, os picos centrados em aproximadamente 1018, 996, 900 e 840 cm-1, denunciam a presença de estruturas biogênicas ligadas à presença de ácidos nucleicos (riboses e grupos fosfatos). Investigou-se, também, a possibilidade de certas assinaturas biológicas serem mascaradas pela presença de gases quando observadas remotamente. A conclusão é que as bandas de gases como o SO2 (1136 cm-1), O3 (1042 e 1124 cm-1) e C2H6 (826 cm-1), podem tornar a detecções de algumas bioassinaturas uma tarefa árdua e até mesmo impossível. Outras perguntas de pesquisa ligadas à determinação da quantidade mínima de material biológico capaz de oferecer um sinal que possa ser identificado e atribuído a um material biológico específico, assim como a possibilidade de determinação de uma banda de absorção apta a servir como fator de calibração foram abordadas. Conclui-se que há possibilidades de se detectar alguma característica biológica mesmo após diluições cobrindo 5 ordens de magnitude (variação de 760 a 0.076 ng/µl). A banda centrada em 893 cm-1 pode ser utilizada para futuras calibrações, pois responde linearmente com a variação da quantidade de material biológico. O resultado da pesquisa mostrou que existem bandas moleculares em comum entre a atmosfera e o material biológico, sendo atribuídas a potenciais marcadores moleculares que, possivelmente, poderão ser detectados de forma remota em futuras missões espaciais. / It is notorious that interest in detecting life beyond Earth has increased in the scientific world. The existence of possible biological markers the terrestrial atmosphere, the presence of living material or organic material decomposed on surfaces and at the sea increase the chances of success of the research. Life on Earth is everywhere and the planet is saturated with its manifestations. The objective of this thesis is the development of a methodology that offers ideas for the detection of bioassinatures outside the Earth, particularly in exoplanets. In terms of molecular biology, the main signature of life is DNA (desoxyribonucleic acid), which organizes and hosts the genetic code all of the living things. Other molecules that denounce the presence of life are chlorophyll, carotenoids, DNA fragments, organic molecules, etc. In an attempt to find bioassinatures in the atmosphere of exoplanets, a requirement must be met: the identification of characteristic bands that allow the detection of a signal associated with a complex biomolecule, preferably in the infrared region, seen in the middle of the peaks of gases atmospheric conditions. Thus, a series of spectral analyzes were performed for DNA samples/cells of the extremophilic microorganism Halobacterium salinarum, to be compared to the infrared spectrum obtained directly from the Earths atmosphere. The search for specific markers was performed in order to determine the peaks that allow the detection of these singular components when suspended in atmospheric gases. The results of the research show that the Earths atmosphere is contaminated with complex molecules. There is a total of 37 common absorptions found in the spectrum of the Earths atmosphere and in Cells or DNA spectra (for example 966, 936, 924, 886 and 866 cm-1). Among them, the peaks centered at approximately 1018, 996, 900 and 840 cm-1, denote the presence of biogenic structures linked to the presence of nucleic acids (riboses and phosphate groups). It was also investigated the possibility of certain biological signatures being masked by the presence of gases when observed remotely. The conclusion is that gas bands such as SO2 (1136 cm-1), O3 (1042 and 1124 cm-1) and C2H6 (826 cm-1) can make the detection of some bioassinatures a difficult task. Other research questions related to the determination of the minimum quantity of biological material can providing a signal capable of being identified and assigned to a specific biological material, as well as the possibility of determining an absorption that could a serving as a calibration factor were addressed . It is concluded that it is possible to detect a same biological characteristic after dilutions covering 5 orders of magnitude (ranging from 760 to 0.076 ng/µl). The band centered at 893 cm-1 can be used for future calibrations because it responds linearly with the variation of the amount of biological material. The research results showed that there are molecular bands in common between the atmosphere and biological material and are attributed to potential molecular markers that may possibly be detected remotely in future space missions.
553

The role of large woody debris on sandy beach-dune morphodynamics

Grilliot, Michael J. 30 April 2019 (has links)
Coastal foredune evolution involves complex processes and controls. Although a great deal is known about the effects of vegetation cover, moisture, and fetch distance on sediment supply, and of topographic forcing on airflow dynamics, the role of large woody debris (LWD) as a modulator of sediment supply and a control on foredune growth is understudied. Large assemblages of LWD are common on beaches near forested watersheds and collectively have a degree of porosity that increases aerodynamic roughness and provides substantial sand trapping volume. To date, no research has attempted to understand the geomorphic role that LWD matrices, as a whole, have as roughness elements affecting airflow and sediment transport across a beach-dune system, or, what the long-term implications of these impacts are on beach and foredune erosion recovery and evolution. This four-year research initiative investigated the role of a LWD matrix on beach-dune morphodynamics on West Beach, Calvert Island on the central coast of British Columbia, Canada. This study integrated data from research that spanned three temporal scales, 1) event-scale (10 min) flow and sediment transport patterns, 2) daily frequency and relative magnitude of landscape changing events, 3) seasonal to interannual-scale volumetric and LWD changes. An event-scale experiment to characterise airflow dynamics and related sand transport patterns showed that LWD distinctly alters wind flow patterns and turbulence levels from that of incoming flow over a flat beach. Overall, mean wind speed and fluctuating flow properties declined as wind transitioned across the LWD. Streamwise mean energy was converted to turbulent energy, however, the reductions in mean flow properties were too great for the increased streamwise turbulence to have an effect on transport. In response to these flow alterations and more limited sand transport pathways to the foredune, sediment flux was reduced by 99% in the LWD compared to the open beach, thereby reducing sand supply to the foredune. Sand grains rebounding off of the LWD were carried higher into the flow field resulting in greater mass flux recorded at 20-50 cm in the LWD as opposed to the flat beach. This effect was only recorded 6 m into the LWD. As such, LWD has the potential to modulate rates of foredune recovery, growth, and evolution. Time-lapse photography collected at 15 min intervals during the study revealed that storm events lead to wave-induced erosion of the backshore and reworking of the LWD matrix. The exposed LWD matrix subsequently traps aeolian sediment that leads to rapid burial of the LWD and building of a raised platform for emergent vegetation. However, infilling of the accommodation space within the LWD matrix is so rapid, that sediment starvation of the foredune is short-lived. While the LWD at this site does trap sediment in the backshore, helping to protect the dune from scarping, LWD at this study site maintains an overall lower impact on transport to the foredune. Critical to this relationship is the frequency and magnitude of nearshore events that erode the beach periodically and re-organize the LWD matrix, which directly impacts the ability of LWD to store sediment and modulate transport to the foredune. A conceptual model exploring these relationships is presented. / Graduate
554

Mamíferos de maior porte em paisagens tropicais alteradas: seu papel em cascatas tróficas e fatores que determinam sua distribuição / Large mammals in altered tropical forest landscapes: their role in trophic cascade and factors that determine their distribution

Oliveira, Gustavo de 17 November 2011 (has links)
Nesta dissertação investigamos o papel dos mamíferos em cascatas tróficas nas florestas tropicais, e os efeitos da configuração espacial e qualidade do habitat assim como das atividades humanas atuais sobre a distribuição de mamíferos de maior porte em uma paisagem rural de Mata Atlântica. No primeiro capítulo, através de uma revisão da literatura sumarizamos e avaliamos a evidência empírica de que mamíferos estão envolvidos em cascatas tróficas em florestas tropicais com o objetivo de indicar os avanços, os problemas e os desafios nessa área. Poucos estudos empíricos e conceituais foram encontrados na literatura, todos realizados nas últimas três décadas, enquanto que a maioria dos estudos empíricos foi realizada nos Neotrópicos. Grande parte das hipóteses relacionadas a cascatas tróficas foi apenas proposta, e considera o homem como predador de topo. Além da maior parte das variáveis quantificadas não serem adequadas para demonstrar efeitos em cascata, a escala temporal da maioria dos estudos revisados foi curta para acessar estes efeitos sobre a comunidade de plantas que contém espécies longevas. Nenhuma hipótese abordou o efeito dos predadores de topo sobre as populações de presas pequenas via o controle da densidade e distribuição de mesopredadores. A maioria das hipóteses que encontramos na literatura se refere a outros efeitos indiretos causados por mamíferos, em particular através da dispersão de sementes e da disponibilização de nutrientes via fezes. Dessa maneira, demonstramos que o termo \"cascata trófica\" tem sido utilizado amplamente, englobando outros efeitos indiretos que se propagam via outras interações que não tróficas, e que a evidência empírica disponível até o momento de que mamíferos desencadeiam cascatas tróficas em florestas tropicais é pequena. No segundo capítulo, através da amostragem de 23 remanescentes florestais e do uso de modelos de ocupação e da abordagem de seleção de modelos, investigamos como fatores associados à configuração espacial e qualidade do habitat e a outras atividades humanas em andamento interagem e condicionam a distribuição de mamíferos terrestres de maior porte em paisagens intensamente modificadas pelo homem. A assembléia de mamíferos de maior porte encontrada na paisagem estudada é simplificada e dominada por mamíferos silvestres generalistas de médio porte, sugerindo que o controle de mesopredadores e a regeneração das florestas podem estar comprometidos. Os resultados também sugerem que: (1) a distribuição de mamíferos de maior porte deve ser condicionada mais por fatores associados à configuração espacial do que à qualidade do habitat florestal; (2) as atividades humanas atuais são tão ou mais importantes que a configuração espacial e a qualidade do habitat para a maioria das espécies. O tamanho dos fragmentos e a distância a rodovias, entre os fatores associados à configuração espacial, e a caça e a presença do cachorro doméstico, entre as atividades humanas atuais, foram particularmente importantes para a distribuição das espécies de mamíferos de maior porte. A relevância das atividades humanas em andamento sugere que estratégias de manejo que foquem em mudanças na atitude da população humana, através de programas de conscientização e educação, podem ter resultados significativos em termos da persistência de populações de mamíferos em paisagens rurais. / In this dissertation we investigated the role of large mammals in trophic cascades in tropical forests, and the effects of habitat configuration and quality as well as of current human activities on the distribution of large mammals in a rural Atlantic forest landscape. In the first chapter, through a literature review we summarized and evaluated the empirical evidence that mammals are involved in trophic cascades in tropical forest, with the aim of highlighting the progress, problems and challenges in this area. Few conceptual and empirical studies were found in the literature, all of which were performed in the last three decades, while most of the empirical studies were developed in the Neotropics. Most of the hypotheses related to trophic cascades were only proposed and not tested, and considered humans as top predators. Not only most of the quantified variables were not appropriate to demonstrate cascading effects, but also the temporal scale of most studies was short to detect these effects on plant communities composed of long-lived species. We did not find hypotheses addressing the effect of top predators on the populations of small prey through the control of mesopredator density and distribution. Most hypotheses in the reviewed literature refer to other indirect effects played by mammals, especially through seed dispersal and nutrient allocation via feaces. Thus, we demonstrate that the term \"trophic cascade\" has been used widely, encompassing other indirect effects that propagate through other, non-throphic interactions, and that the empirical evidence available so far that mammals are drivers of trophic cascades in tropical forest is weak. In the second chapter, through the sampling of 23 forest fragments and using occupancy models and a model selection approach, we investigated how factors associated with habitat configuration and quality and with other current human activities interact to define the distribution of terrestrial large mammals in human-modified landscapes. The large mammal assemblage from the studied landscape is impoverished and dominated by medium-sized generalist species, suggesting that both the control of mesopredators and forest regeneration may be compromised. Our results also suggest that: (1) the distribution of large mammals is determined mainly by aspects of habitat configuration rather than by aspects of habitat quality, and (2) current human activities are equally or more important than habitat configuration and quality for most of the species. Fragment size and distance to roads, among the factors associated with habitat configuration, and hunting pressure and domestic dog presence, among those associated with current human activities, were particularly important to the distribution of large mammal species. The relevance of current human activities suggests that management strategies that focus on changing people attitudes, through programs of education, can have significant results in terms of the persistence of mammal populations in rural landscapes.
555

The biogeography and conservation status of the rocky plateaus of the northern Western Ghats, India

Thorpe, Christopher John January 2018 (has links)
Rocky plateaus are globally threatened ecosystems and the lateritic plateaus in northern section of the Indian Western Ghats/Sri Lanka Biodiversity Hotspot (NWG) are notable landscape features. The NWG are geologically distinct from and biologically isolated from the other two sections of the Western Ghats. The NWG is known to possess elevated levels of endemic flora their biotic relationships remain poorly understood. We present here the first quantitative multi-taxa comparative study of plateau fauna in the northern Western Ghats. Ants, water beetles and amphibians were selected for the comparison as they use different ecological resources from each other and at various times of year therefore may provide a wider representation of plateau usage. Distribution and endemism were expected to reflect distribution and isolation by plateau and inter-plateau environment related to elevational, latitudinal, climatic and land-use clines. The study explored patterns of amphibian, water beetle, ant and fungal distribution and sampling seasonal pools and terrestrial surfaces of 13 representative plateaus in western Maharashtra, with sites ranging from 67-1179 m and across 2° of (sub) tropical latitude. Distribution of all taxonomic groups was spatially non-random at all levels of organisation and across all spatial scales. At the macroscale assemblages differed significantly with climate related to elevation, latitude but at a local scale land-use and microhabitat availably had an impact. Ants displayed a large seasonal assemblage variation, responding to seed availability. Water beetles the ants (combined survey data) were the best surrogates for all taxa data with amphibians the weakest representatives. Infection by the fungal pathogen, Batrachochytrium dendrobatidis, was extensive but less intense below the escarpment. We report the first records of infection in 13 endangered and data deficient amphibian species in the Western Ghats. The plateaus of western Maharashtra have recently been recognised as fragile and threatened ecosystems most still lack adequate statutory protection. In the absence of peer reviewed comparative data, the importance of individual sites is difficult to demonstrate hampering evidence-based conservation decisions.
556

Ocorrência e distribuição de isópodos terrestres (Crustacea: Oniscidea) em três ambientes florestais na Serra Geral, Rio Grande do Sul

Bugs, Priscila da Silva January 2010 (has links)
A subordem Oniscidea Latreille, 1829 é a única ordem de Isopoda que abriga espécies verdadeiramente terrestres. Formam um importante e dominante componente nas comunidades de meso e macro-decompositores de solo. Suas atividades causam um impacto considerável na decomposição através da promoção da respiração microbial e alterações na química dos detritos. No presente estudo investigou-se a abundância, diversidade e composição de espécies de isópodos terrestres em três formações vegetais, na Serra Geral do Rio Grande do Sul – Brasil. A área compreende duas formações espontâneas (Mata Primária e Mata Secundária) e área de plantação de Pinus abandonada, em estágio de sucessão. Para cada área, foram consideradas duas subáreas, contendo dois transectos com 5 armadilhas de queda em cada um, as quais ficaram operantes de 2001 a 2002. Os dados obtidos possibilitaram a realização de inferências sobre as características populacionais apresentadas por duas espécies: Atlantoscia floridana e Balloniscus glaber. Atlantoscia floridana é a espécie mais frequente nas três áreas: 145 indivíduos em Mata Primária, 194 em Mata Secundária e 105 em plantações de Pinus. Balloniscus glaber apresentou abundância de 80 indivíduos em Mata Primária, 82 em Mata Secundária e um indivíduo em plantações de Pinus. A Análise de Similaridade revelou diferença quantitativa entre as áreas, mas não diferença qualitativa. Foram identificados Doubletons para mata primária (Alboscia silveirensis) e plantação de Pinus (Benthana araucariana) e Singletons para a mata secundária (A. silveirensis, B. araucariana e Styloniscus otakensis) e plantação de Pinus (B. glaber). Obteve-se também o registro de uma Duplicata (A. silveirensis) para mata primária e secundária. A Proporção Sexual Operacional (OSR) de A. floridana seguido do Teste G, não verificou diferença entre a proporção sexual apresentada dentro das áreas ou em relação ao esperado 1:1. Atlantoscia floridana apresentou correlação significativa entre o tamanho da fêmea e o tamanho da prole para as três áreas. A menor fêmea ovígera foi encontrada em área de Pinus (0.968mm). Fêmeas ovígeras e pós-ovígeras ocorreram nas estações de verão, outono e primavera (Mata Primária e Plantação de Pinus) e nas quatro estações (Mata Secundária). Quanto à abundância de A. floridana não apresentou diferença significativa entre as áreas. Representantes de todas as classes ocorrem em todas as áreas. Para Balloniscus glaber a Proporção Sexual Operacional (OSR) seguido do Teste G verificou diferença quanto à proporção esperada de 1:1, mas não diferença entre as áreas. Não foi apresentada correlação significativa entre o tamanho da fêmea e o tamanho da prole na Mata Primária e Mata Secundária. Fêmeas ovígeras e pósovígeras ocorreram nas estações de verão e outono (Mata Primária e Mata Secundária). Quanto à abundância B. glaber não apresentou diferença significativa entre as áreas. Representantes de todas as classes ocorrem na Mata Primária e Mata Secundária. Em Plantação de Pinus ocorreu o registro de somente uma fêmea no verão de 2001. A menor fêmea ovígera foi encontrada em Mata Primária. / The suborder Oniscidea Latreille, 1829 is the only Isopoda order that has truly terrestrial species. This group is an important and dominant portion of the soil meso and macro faunal community. Their activity causes considerable impact in decomposition through the increase on microbial respiration and detritus chemical alteration. The present study investigated the abundance, diversity, and species composition of terrestrial isopods in three vegetal formations in the Serra Geral of Rio Grande do Sul – Brazil. The area comprises two spontaneous formations (primary and secondary forests) and an abandoned Pinus plantation in succession stage. For each area, two sub-areas were taken into account; constituting two transects containing 10 pitfall traps each, that where kept during 2001 and 2002. The obtained data permitted inferences regarding the population characteristics of two species: Atlantoscia floridana and Balloniscus glaber. Atlantoscia floridana was the most frequent species in the three areas: 145 individuals in primary forest, 194 in secondary forest and 105 in Pinus plantation. Balloniscus glaber presented an abundance of 80 individuals in primary forest, 82 in secondary forest and one individual in Pinus plantation. The similarity analysis revealed quantitative but not qualitative difference between the areas. Doubletons were identified in primary forest (Alboscia silveirensis) and Pinus plantation (Benthana araucariana) and Singletons were identified for secondary forest (A. silveirensis, B. araucariana and Styloniscus otakensis) and Pinus plantation (B. glaber). One Duplicata (A. silveirensis) was also registered for primary and secondary forest. The operational sexual proportion (OSR) of A. floridana followed by G Test was not different between observed and expected 1:1 sexual proportion in the areas. Atlantoscia floridana presented significant correlation between female size and offspring number in the three areas. The smallest ovigerous female was found in the area with Pinus (0.968mm). There was no difference in the abundance of ovigerous and post ovigerous females. Both females were present in the samples from summer, fall and spring (primary forest and Pinus plantation) or in the four seasons (secondary forest). Regarding the abundance of Atlantoscia floridana, there was no significant difference between the different areas. Individuals of all classes were present in all areas. The OSR of B. glaber had no significant difference between the sampled number of females and males. Through G Test it was verified difference from the expected 1:1 proportion, but no difference between the areas. There was no significant correlation between female size and offspring number for primary and secondary forest. There was no significant difference regarding the abundance of ovigerous and post ovigerous females. Both females were present in the samples from summer and fall (primary and secondary forest). There was no significant difference in abundance of B. glaber between the areas. Individuals of all classes were present in primary and secondary forest. In Pinus plantation, there was only one female in the summer of 2001. The smallest ovigerous female was found in primary forest.
557

Aplicação de fotogrametria terrestre digital na análise de descontinuidades em maciços rochosos: exame comparativo com técnicas tradicionais / Aplication of digital terrestrial photogrammetry on discontinuities analysis in rock mass: comparative exame with traditional techniques

Fernandes, Fabiana Santos 07 May 2010 (has links)
A análise estrutural das descontinuidades e da tectônica rúptil atuante em um maciço rochoso é uma abordagem essencial em vários campos da geologia aplicada. No presente trabalho utilizou-se de técnicas tradicionais de levantamentos estruturais de detalhe via linha de varredura (scanlines) e técnicas de fotogrametria terrestre digital para a análise das descontinuidades de um maciço rochoso. Os resultados obtidos através de duas técnicas de caracterização foram comparados. Os trabalhos foram desenvolvidos em uma mina de metacalcário incluída no Grupo São Roque, situada próximo à borda leste da Bacia do Paraná, e próxima a grandes estruturas transcorrentes do sudeste do Estado de São Paulo. Foram amostrados taludes com direções ortogonais entre si visando uma amostragem que fosse tridimensionalmente representativa. Quando o levantamento foi efetuado através de técnicas tradicionais lineares, as estruturas preferencialmente amostradas foram aquelas com as direções perpendiculares à direção de amostragem. Inversamente as amostragens por fotogrametria terrestre digital evidenciaram as estruturas paralelas ao plano de levantamento. Os resultados foram bastante semelhantes em termos das atitudes das estruturas planares. O levantamento clássico mostrou-se bastante demorados, porém com análise mais direta, enquanto o levantamento fotogramétrico ofereceu uma abrangência maior, porém com tratamento e análise dos dados mais trabalhosos. Embora seja uma nova tecnologia que pode agilizar os levantamentos, um controle in situ se faz necessário. / Structural analysis of discontinuities in a brittle rock mass is an essential approach in various fields of applied geology. In this study we used traditional techniques of structural detail surveys scanlines and techniques of digital terrestrial photogrammetry for the analysis of discontinuities of rock mass. The results obtained by the two characterization techniques were then compared. The work was carried out in a limestone mine included in the São Roque Group, located near the eastern edge of the Paraná Basin, and near large transcurrent shear zones that occurs in the southeastern State of São Paulo. Slopes were sampled within orthogonal directions to each one in order to take a three-dimensional representative sample. When the survey was carried out using traditional linear techniques the structures preferentially sampled were those with the directions perpendicular to the direction of sampling. Conversely, sampling by digital photogrammetry showed that structures parallel to the survey. The results were quite similar in terms of the attitudes of planar structures. The classic survey proved to be very time consuming, but with more direct analysis, while the photogrammetric survey offered a bigger coverage, but with treatment and analysis more hard-working. Although it is a new technology that can speed up the surveys, an in situ control is necessary.
558

A Terra como um exoplaneta / Earth as exoplanet

Bernardes, Luander 29 November 2018 (has links)
É notório o fato de que o interesse pela detecção de vida fora da Terra tenha aumentado no mundo científico. A existência de possíveis traçadores biológicos na atmosfera terrestre, a presença de material vivo ou de material orgânico decomposto em superfícies e no mar aumentam as possibilidades de sucesso das pesquisas. A vida na Terra é encontrada em todas as partes, e o planeta está saturado de suas manifestações. O objetivo da presente tese é o desenvolvimento de uma metodologia que ofereça ideias para a detecção de bioassinaturas fora da Terra, particularmente em exoplanetas. Em termos de biologia molecular, a principal assinatura de vida é o DNA (ácido desoxirribonucleico), que organiza e sedia o código genético de todos os seres vivos. Outras moléculas que denunciam a presença de vida são a clorofila, carotenoides, fragmentos de DNA, moléculas orgânicas, etc. Na tentativa de se encontrar bioassinaturas na atmosfera de exoplanetas, um requisito deve ser atendido: a identificação de bandas características que permitam a detecção de um sinal que esteja associado a uma biomolécula complexa, preferencialmente na região do infravermelho, vista em meio aos picos de gases atmosféricos. Sendo assim, uma série de análises espectrais foram realizadas para amostras de DNA/células do micro-organismo extremófilo Halobacterium salinarum, com a finalidade de serem comparadas ao espectro infravermelho, obtido de forma direta da atmosfera terrestre. A pesquisa por marcadores específicos foi realizada a fim de determinar os picos que permitam a detecção desses componentes singulares quando suspensos em gases atmosféricos. Os resultados da pesquisa mostram que a atmosfera terrestre está contaminada com moléculas complexas. Existem 37 absorções em comum quando se compara o espectro da atmosfera terrestre com os espectros de células ou DNA (por exemplo 966, 936, 924, 886 e 866 cm-1). Entre elas, os picos centrados em aproximadamente 1018, 996, 900 e 840 cm-1, denunciam a presença de estruturas biogênicas ligadas à presença de ácidos nucleicos (riboses e grupos fosfatos). Investigou-se, também, a possibilidade de certas assinaturas biológicas serem mascaradas pela presença de gases quando observadas remotamente. A conclusão é que as bandas de gases como o SO2 (1136 cm-1), O3 (1042 e 1124 cm-1) e C2H6 (826 cm-1), podem tornar a detecções de algumas bioassinaturas uma tarefa árdua e até mesmo impossível. Outras perguntas de pesquisa ligadas à determinação da quantidade mínima de material biológico capaz de oferecer um sinal que possa ser identificado e atribuído a um material biológico específico, assim como a possibilidade de determinação de uma banda de absorção apta a servir como fator de calibração foram abordadas. Conclui-se que há possibilidades de se detectar alguma característica biológica mesmo após diluições cobrindo 5 ordens de magnitude (variação de 760 a 0.076 ng/µl). A banda centrada em 893 cm-1 pode ser utilizada para futuras calibrações, pois responde linearmente com a variação da quantidade de material biológico. O resultado da pesquisa mostrou que existem bandas moleculares em comum entre a atmosfera e o material biológico, sendo atribuídas a potenciais marcadores moleculares que, possivelmente, poderão ser detectados de forma remota em futuras missões espaciais. / It is notorious that interest in detecting life beyond Earth has increased in the scientific world. The existence of possible biological markers the terrestrial atmosphere, the presence of living material or organic material decomposed on surfaces and at the sea increase the chances of success of the research. Life on Earth is everywhere and the planet is saturated with its manifestations. The objective of this thesis is the development of a methodology that offers ideas for the detection of bioassinatures outside the Earth, particularly in exoplanets. In terms of molecular biology, the main signature of life is DNA (desoxyribonucleic acid), which organizes and hosts the genetic code all of the living things. Other molecules that denounce the presence of life are chlorophyll, carotenoids, DNA fragments, organic molecules, etc. In an attempt to find bioassinatures in the atmosphere of exoplanets, a requirement must be met: the identification of characteristic bands that allow the detection of a signal associated with a complex biomolecule, preferably in the infrared region, seen in the middle of the peaks of gases atmospheric conditions. Thus, a series of spectral analyzes were performed for DNA samples/cells of the extremophilic microorganism Halobacterium salinarum, to be compared to the infrared spectrum obtained directly from the Earths atmosphere. The search for specific markers was performed in order to determine the peaks that allow the detection of these singular components when suspended in atmospheric gases. The results of the research show that the Earths atmosphere is contaminated with complex molecules. There is a total of 37 common absorptions found in the spectrum of the Earths atmosphere and in Cells or DNA spectra (for example 966, 936, 924, 886 and 866 cm-1). Among them, the peaks centered at approximately 1018, 996, 900 and 840 cm-1, denote the presence of biogenic structures linked to the presence of nucleic acids (riboses and phosphate groups). It was also investigated the possibility of certain biological signatures being masked by the presence of gases when observed remotely. The conclusion is that gas bands such as SO2 (1136 cm-1), O3 (1042 and 1124 cm-1) and C2H6 (826 cm-1) can make the detection of some bioassinatures a difficult task. Other research questions related to the determination of the minimum quantity of biological material can providing a signal capable of being identified and assigned to a specific biological material, as well as the possibility of determining an absorption that could a serving as a calibration factor were addressed . It is concluded that it is possible to detect a same biological characteristic after dilutions covering 5 orders of magnitude (ranging from 760 to 0.076 ng/µl). The band centered at 893 cm-1 can be used for future calibrations because it responds linearly with the variation of the amount of biological material. The research results showed that there are molecular bands in common between the atmosphere and biological material and are attributed to potential molecular markers that may possibly be detected remotely in future space missions.
559

Diel Patterns of Foraging Aggression and Antipredator Behavior in the Trashline Orb-weaving Spider, Cyclosa turbinata

Watts, James C 01 May 2014 (has links)
Few studies have rigorously assessed the adaptive value of diel rhythms in animals. We laid the groundwork for assessing the adaptive rhythm hypothesis by assaying diel rhythms of foraging and antipredator behavior in the orb-weaving spider Cyclosa turbinata. When confronted with a predator stimulus in experimental arenas, C. turbinata exhibited thanatosis behavior more frequently and for longer durations during the day. However, assays of antipredator response within webs revealed more complex diel patterns of avoidance behaviors and no pattern of avoidance behavior duration. Assays of prey capture behavior found that the likelihood of exhibiting prey capture behavior varied significantly across times of day and test subjects, but only test subject predicted attack latencies. Although C. turbinata foraging aggression changed over the diel cycle, we found no evidence of a trade-off between foraging behavior and predator vigilance. However, overall patterns of vigilance may be masked by diel changes in antipredator strategies.
560

Genetic Variation in Long-Term and Short-Term Physiological Changes in Daphnia magna During Acclimation to High Temperature

coggins, bret l 01 May 2016 (has links)
The aquatic zooplankton crustacean Daphnia magna must be able to tolerate thermal stress in order to survive their native shallow ponds that are susceptible to drastic seasonal and diurnal temperature fluctuations as well as to globally increasing temperatures. Survival in such variable environments requires plastic responses that must include fundamental aspects of Daphnia biochemistry and physiology. Adaptive response to selection favoring such plastic phenotypes requires the presence of genetic variation for plastic response in natural populations. Adverse effects of elevated temperature on aquatic organisms are diverse and so are their plastic responses; among the most severe challenges aquatic organisms face when exposed to heat is the elevated oxidative stress. In this work we focused on short-term and long-term responses of Daphnia to temperature changes that increase its resistance to oxidative stress. Daphnia acclimated to stressful but non-lethal temperature (28ºC) show longer survive during exposure to a lethal temperature (37ºC) than those acclimated to the optimal temperature (18ºC). Short-term reciprocal switches between 18ºC and 28ºC result in intermediate temperature tolerance. These changes are accompanied by mirroring changes in total antioxidant capacity indicating the increased antioxidant capacity as a possible causative mechanism for heat tolerance gained from acclimation. The analysis of 6 geographically distinct genotypes representing a range of temperature tolerance levels shows a genetic difference in response to short-term and long-term acclimation as well as in the effect of antioxidant capacity on temperature tolerance. These results indicate a significant degree of local adaptation in heat and oxidative stress defenses in Daphnia and provide a better understanding of adaptive responses of this zooplankton crustacean to rising temperatures.

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