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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.
161

An investigation of environmental factors impacting on diarrhoea in children under five years old in Akakikality sub city, Addis Ababa, Ethiopia

Zeyede Kassa Mandefro 16 February 2015 (has links)
The purpose of this study was to investigate the environmental factors that impact on childhood diarrhoea in children under five years old in Akakikality sub city Addis Ababa, Ethiopia. Objectives of the study were to determine the prevalence of diarrhoea and to determine the environmental factors that impact on diarrhoea in children under five years old. A survey was done and a non-experimental approach was used in this descriptive and analytical quantitative study using a cross sectional study design. The instrument was a self-designed questionnaire. The target population for this study was all mothers or caretakers of children under five years found in the described study context – the sample size was 299. In this study 12.7% of the children had diarrhoea during the survey. Proper utilization of toilets, hand washing and safe storage of water in the households using narrow mouthed water containers were significant predictors of diarrhoea in the children. / Health Studies / M.A. (Public Health)
162

An organizational capacity model for Portuguese wine cooperatives

Souza, Maria de Fátima Arruda 15 September 2019 (has links)
The purpose of this research is to develop a model of organizational capacity that can potentially lead wine cooperatives to achieve success, exploring the factors in the environment that affect their performance and present preliminary criteria to evaluate organizational capacity based on the model. Cooperatives are organizations with particular characteristics. Apart from having sharing cooperative principles and values, there is a dual nature to their purpose that has been noted in the literature. Cooperatives have both an economic and a social dimension: they are simultaneously a business and non-profit driven organizations owned by their members and controlled by them democratically. The aim of cooperatives is to maximise members’ service and satisfaction. Financial indicators alone are not suitable to assess cooperatives’ performance since they are not for-profit organization. So, the construct of organizational capacity, developed to assess the potential of non-profit organizations (NPO) to achieve their goals, was adapted to wine cooperatives in Portugal. Although there are models of organizational capacity for NPO, they do not fit the reality of cooperatives mainly because of their economic role. Cooperatives are also economically oriented businesses. A grounded theory approach was adopted for this research, which is a qualitative methodology that intends to systematically obtain and analyse data in social research to generate theory. Cooperatives were selected through theoretical sampling, aiming to reach cooperatives that could represent the diversity of the universe of 67 wine cooperatives in Portugal in 2015. Twenty-three people (members and managers) were interviewed in 19 wine cooperatives and unions in different regions of the country. The model of organizational capacity in the environment of wine cooperatives was developed taking into account the categories that emerged from data. The model provides a systemic view of the wine cooperative environment and has three sets of categories: members, environmental factors and the cooperative itself. The two categories that compose this last set are cooperative identity and organizational capacity. The core category in the model of organizational capacity in wine cooperatives is management because it is the required ability of managers that allows them to coordinate the environmental factors and other capacities of the cooperative. / O objetivo desta pesquisa é desenvolver um modelo de capacidade organizacional capaz de gerar o potencial de conduzir as adegas cooperativas ao sucesso, identificando os fatores ambientais que afectam o seu desempenho e propor critérios para avaliar a capacidade organizacional das adegas cooperativas a partir do modelo. As cooperativas são organizações com características muito próprias. Para além de partilharem os princípios e valores cooperativos, uma dualidade de propósito tem sido identificada na literatura. As cooperativas têm tanto uma dimensão económica como uma dimensão social: são simultaneamente um negócio e organizações sem fins lucrativas que pertencem e são controladas pelos seus associados, democraticamente. A finalidade das cooperativas é maximizar os serviços e a satisfação dos associados. Indicadores financeiros não são adequados para avaliar o desempenho das cooperativas, pois estas não são organizações que visam lucro. Assim, o constructo capacidade organizacional, desenvolvido para avaliar o potencial das organizações sem fins lucrativos (OSFL) de atingir seus objetivos, foi adaptado para as adegas cooperativas Portuguesas. Embora existam modelos de capacidade organizacional para OSFL, eles não se adequam à realidade das cooperativas dado o seu papel económico. As cooperativas são também negócios com orientação económica. A abordagem de pesquisa foi a teoria fundamentada, uma metodologia qualitativa que pretende obter e analisar dados sistematicamente em pesquisa social para gerar teoria. As cooperativas foram selecionadas através da amostragem teórica, buscando incluir cooperativas que pudessem representar a diversidade do universo de 67 adegas cooperativas existentes em Portugal em 2015. Vinte e três pessoas (associados e gestores) foram entrevistados em 19 adegas cooperativas e uniões, em diferentes regiões do país. O modelo de capacidade organizacional no ambiente das adegas cooperativas foi desenvolvido levando em consideração as categorias que surgiram nas entrevistas. O modelo proporciona uma visão sistêmica do ambiente das adegas cooperativa e apresenta três conjuntos de categorias: associados, factores ambientais e a cooperativa. As duas categorias que compõem este último grupo são a identidade cooperativa e a capacidade organizacional. A categoria central do modelo de capacidade organizacional em adegas cooperativas é gestão pois é a habilidade necessária aos gestores que lhes permite coordenar os factores ambientais e as outras capacidades da cooperativa.
163

Avaliação das curvas de lactação de rebanhos holandeses nos estados de Minas Gerais e São Paulo / Evaluation of the lactation curves of Holstein cows from herds in Minas Gerais and São Paulo

Dias, Juliana 16 December 2011 (has links)
A curva de lactação é a descrição gráfica da produção de leite em dado período de tempo, normalmente descrita por modelos matemáticos dos quais podem ser obtidos fatores multiplicativos de predição e estimativas de interesse econômico como o pico, persistência e produção acumulada aos 305 dias. Entretanto, faz-se necessário a seleção de funções de curvas para que as estimativas obtidas apresentem o menor erro de predição associado, bem como, identificar os fatores que influenciam a curva de lactação para que essas estimativas sejam desprovidas de tais fontes de variação. Desta forma, foram utilizadas cinco funções não lineares para modelar 10.679 lactações pertencentes a vacas holandesas, de grupo genético PCOD (puro por cruza de origem desconhecida), PCOC (puro por cruza de origem conhecida) e PO (puro de origem), pertencentes a 38 rebanhos agrupados em três níveis de produção, situados nos estados de São Paulo e Minas Gerais no período de 1997 a 2009. A seleção da função baseou-se simultaneamente no maior valor do coeficiente de determinação e nos menores valores do quadrado médio do erro de predição, raiz quadrada do quadrado médio do erro de predição, critério bayesiano de informação e percentual de curvas atípicas. Independente do nível de produção e ordem de lactação, dentre os modelos avaliados, a função de Wood obteve o melhor ajuste e, portanto, foi utilizada para obter estimativas de pico, tempo de ascensão ao pico, persistência e produção acumulada aos 305 dias. Posteriormente, avaliou-se a influência de fatores ano de parto, época de parto, ordem de lactação, rebanho, nível de produção e duração da lactação sobre os parâmetros a (produção inicia), b (taxa de acréscimo na produção até o pico) e c (taxa de decréscimo na produção após o pico de lactação) e estimativas de pico, tempo de pico, persistência e produção acumulada aos 305 dias das curvas de lactação modeladas pela função de Wood. Em seus respectivos níveis de produção, as médias dos parâmetros e estimativas aumentaram proporcionalmente às classes de duração da lactação e maiores estimativas foram observadas para multíparas na época seca do ano. Dado o exposto, para os rebanhos em estudos, fatores de predição da produção de leite aos 305 dias podem ser construídos de acordo com o nível de produção, ordem, época e duração da lactação. / The lactation curve is a graphic depiction of milk production in a given period of time, usually described by mathematical models which can be obtained by multiplicative factors of prediction and estimates of economic interest as the peak, persistence and cumulative production to 305 days. However, it is necessary to select the functions of curves obtained for the estimates have the smallest prediction error associated, as well as to identify factors that influence the lactation curve for these estimates are devoid of these sources of variation. Thus, five were used to model nonlinear functions belonging to 10,679 lactations Holsteins, genetic group PCOD (pure by crosses of unknown origin), PCOC (pure by crosses of known origin) and PO (pure original), belonging to 38 herds grouped in three levels of production, located in São Paulo and Minas Gerais from 1997 to 2009. The function selection was based on both the greater coefficient of determination and lower values of mean square prediction error, the square root of mean square prediction error, Bayesian information criterion and the percentage of atypical curves. Regardless of the level of production and parity among the models evaluated, the function of Wood obtained the best fit and therefore was used to estimate the peak, rise time to peak, persistence and cumulative production to 305 days. Subsequently, we evaluated the influence of year of birth, season of calving, lactation order, herd production level and duration of lactation on the parameters a (production starts), b (rate of increase in production to peak) and c (rate of decline in production after peak lactation) and estimates of peak, peak time, persistence and cumulative production to 305 days of lactation curves modeled by the function of Wood. In their production levels, the mean estimates of parameters and increased proportionally to the classes of lactation length and higher estimates were observed for multiparous in the dry season. Given the above, for livestock studies, predictors of milk production to 305 days can be constructed according to the level of production, order, timing and duration of lactation.
164

Condições socioeconômicas e ambientais associadas à hanseníase na Bahia, Brasil / Socio-economic and environmental effects influencing the development of leprosy in Bahia, Brazil

Miranda, William Cabral de 19 June 2015 (has links)
Introdução: A hanseníase, doença infecciosa crônica, causada pelo bacilo Mycobacterium leprae, tem seu mecanismo de transmissão não totalmente esclarecido. A transmissão ativa pode estar associada a movimentos migratórios, condições sociais ou outras fontes de infecção (como a manutenção do bacilo no ambiente). Objetivos: Descrever o padrão espacial do risco relativo da hanseníase em menores de 15 anos no estado da Bahia; identificar possíveis agrupamentos espaciais e investigar a possível associação entre o risco relativo da hanseníase e fatores socioeconômicos e ambientais. Metodologia: Este estudo ecológico utilizou dados do Sistema de Informação de Agravos de Notificação (SINAN) de 2005 a 2011, do Censo Demográfico do Instituto Brasileiro de Geografia e Estatística de 2010, da Federação das Indústrias do Estado do Rio de Janeiro, Informações Demográficas e Socioeconômicas do Departamento de Informática do SUS, bases cartográficas digitais de dados ambientais do IBGE e bases cartográficas digitais do estado da Bahia e estados vizinhos. Os riscos relativos por município foram padronizados pela covariável gênero. A análise de varredura espacial com o programa SaTScan permitiu verificar a existência de agrupamentos espaciais do tipo alto e/ou baixo. O segundo estágio da análise consistiu em verificar a possível associação entre risco relativo da hanseníase como variável dependente e variáveis socioeconômicas e ambientais como explicativas, através de análises de regressão hierárquica multivariada não espacial e espacial, de acordo com quadro conceitual definido previamente. Resultados: Durante o período de estudo foram notificados 1.674 casos, que representam 7,87% dos casos totais. As taxas em menores de 15 anos, padronizadas por gênero, diminuiu de 0,89/10.000 em 2005 para 0,57 em 2011. A estatística de varredura espacial identificou 4 agrupamentos de risco alto e 6 de risco baixo. No modelo de regressão hierárquica, o risco relativo foi associado positivamente com porcentagem de corpos dágua, Índice de Gini, porcentagem de população urbana, número médio de moradores em domicílios particulares permanentes, e negativamente com o número de residentes nascidos na Bahia. Conclusão: Este estudo mostrou que a hanseníase ainda está ativa no Nordeste do Brasil, principalmente em ambientes urbanos. Embora o risco relativo da hanseníase tenha diminuído, ele ainda permanece muito alto. Migrações de assentamentos rurais para as cidades, bem como mais pessoas vivendo em domicílios e desigualdades sociais são resultados de um processo histórico no nordeste do Brasil, que dão suporte para a continuidade do processo de transmissão da doença. A associação entre o risco relativo da hanseníase e corpos dágua na escala geográfica proposta, indica que a hipótese que associa a M. leprae e ambientes úmidos ainda não pode ser descartada. / Background: Leprosy is a chronic infectious disease caused by the bacillus Mycobacterium leprae. Its mechanism of transmission has not been completely understood. The active transmission may be associated with people migration, social conditions or other sources of infection (such as maintenance of bacilli in the environment). Objectives: To describe the spatial pattern of the relative risk of leprosy in children under 15 years old in the State of Bahia; to identify possible spatial clusters and to investigate the possible association between the relative risk of leprosy with socioeconomic and environmental factors. Methods: This ecological study used data from the Brazilian Disease Notification System (Sistema Nacional de Informação de Agravos de Notificação SINAN) for the studied period of 2005 to 2011; Instituto Brasileiro de Geografia e Estatstica (IBGE 2011), Department of Data and Information Technology (Informações Demográficas e Socioeconômicas do Departamento de Informática do SUS DATASUS, 2010) and the Federation of Industries of the State of Rio de Janeiro FIRJAN (2010), Cartographic base of municipalities in Bahia and surrounding States corresponded to the shape files from the Brazilian Demographic Census. Relative risks were calculated accounting for the respective covariate gender. The spatial scan analysis with SaTScan program allowed to verify the existence of high and/or low spatial clusters. The second stage of the analysis consisted of verifying possible associations between the relative risks of leprosy as a dependent variable, and socio-economic and environmental variables as independent. This was performed using a multivariate regression analysis according to a previously defined conceptual framework. Results: During the study period, 1,674 cases were reported, representing 7.87% of the total cases. Overall rates have decreased from 0.88/10 000 in 2005 to 0.52 in 2011. Spatial scan statistics identified 4 high-risk and 6 low-risk clusters. In the regression model, after allowing for spatial dependence, relative risks were associated with higher percentage of water bodies, higher Gini index, higher percentage of urban population, larger average number of dwellers by permanent residence and smaller percentage of residents born in Bahia. Conclusions: This study showed that leprosy is still active in the Northeast of Brazil, especially in urban environments. Although relative risks of leprosy in Bahia have been decreasing, they remain very high. Migration of rural settlements to the cities, more people living in households and social inequalities are the result of a historical process in northeastern Brazil, that support the continuity of the disease transmission process. The association between relative risks of leprosy and water bodies in the proposed geographic scale indicates that hypothesis linking M. leprae and humid environments cannot be discarded.
165

[en] THE INFLUENCE OF THE ENVIRONMENTAL FACTORS TO THE PERFORMANCE OF PUBLIC SERVICES CONCESSIONS: CASE STUDY ON CEG AND CEG RIO / [pt] A INFLUÊNCIA DOS FATORES MACRO AMBIENTAIS NO DESEMPENHO DE CONCESSÕES DE SERVIÇOS PÚBLICOS: ESTUDO DE CASO DA CEG E DA CEG RIO

SERGIO AUGUSTO PEREIRA BASTOS 14 July 2006 (has links)
[pt] Um amplo rearranjo institucional e de mercado decorreu das privatizações de concessões de serviços públicos no Brasil em diversos setores econômicos. Tornou-se evidente, assim, uma crescente necessidade de estabelecer ações de gestão que produzam o desempenho esperado dessas concessões. Inseridos num ambiente de incertezas, setores regulados, como o de distribuição de gás canalizado, têm sido pouco investigados por pesquisadores no âmbito da gestão estratégica. A presente pesquisa procurou, sob as óticas integrativa e relacional, estudar o efeito dos fatores macro ambientais no desempenho da CEG e da CEG RIO, distribuidoras de gás canalizado do Estado do Rio de Janeiro privatizadas em julho de 1997. De acordo com a metodologia de estudo de caso de Yin, foi adotada a estratégia de triangulação dos métodos. Os dados foram coletados por meio de investigação documental/telematizada, pesquisa de percepções tipo survey via questionário predominantemente estruturado e entrevistas complementares. A interpretação e a análise dos dados foram realizadas com base no referencial teórico apropriado e com o auxílio dos modelos genérico integrativo e relacional de Macedo-Soares. Os resultados evidenciaram a adequação estratégica das empresas, embora os fatores macro ambientais pudessem ser mais estrategicamente orientados. Ainda que o estabelecimento de alianças não seja uma prática estratégica, a análise relacional agrega valor à análise tradicional, contribuindo com novos insights para a tomada de decisão estratégica da CEG e da CEG RIO. O estudo também trouxe contribuições aos referidos modelos de análise estratégica e à gestão de concessões de serviços públicos. / [en] A wide institutional and market reorganization derived from the privatizations of public services concessions in Brazil in economic sectors. It became evident an increasing need to establish business management actions in order to produce the expected performance from those concessions. Embbeded in uncertainties, regulated sectors like piped gas distribution have been underestimated by researchers in respect of strategic management issues. The present research focused, under integrative and relational perspectives, the effect of the environmental factors to the performance of CEG and CEG RIO - gas distribuiton companies in Rio de Janeiro State, privatized in july, 1997. According to Yin´s case study methodology, a triangulation of methods was adopted. Therefore, data was collected through documental/telematized investigation, survey of management perceptions using a mostrly structured questionnaire and complementary interviews. The interpretation and analysis of data were based on the appropriate theoretical reference aided by the generic integrative and the relational models from Macedo-Soares (2000 e 2002). The results highlighted a strategic fit by the companies, although environmental factors could be more strategically oriented. Despite the establishment of alliances not being a strategic practice, the relational perspective added value to the traditional perspective, contributing with new insights to the companies´ strategic decision making processes. The study also brought contributions to the mentioned strategy analysis models and to the management of public services concessions.
166

Estudo das associações de foraminíferos bentônicos recentes na Baía do Almirantado (Ilha Rei George, Antártica) durante três verões austrais consecutivos / Study of the recent benthic Foraminifera assemblages from Admiralty Bay (King George Island, Antartica) during three consecutive austral summers

Rodrigues, André Rosch 19 August 2008 (has links)
A região antártica é foco de constante observação por ser uma região de importante monitoramento climático global. Ao sedimento de fundo marinho está associada uma biota que responde aos processos de alterações ambientais e dentre seus representantes os foraminíferos são considerados bons indicadores marinhos. O objetivo do presente estudo é avaliar a fauna de foraminíferos recentes na Baía do Almirantado durante três verões austral consecutivos (2002/2003, 2003/2004 e 2004/2005) e, através da determinação de algumas variáveis ambientais, compreender melhor a ecologia e a distribuição desses organismos na região. Foram coletadas 56 amostras de sedimento de fundo marinho ao longo da Baía do Almirantado para análise e identificação da fauna de foraminíferos e de variáveis abióticas amostradas na água de fundo e no sedimento. Foram encontradas 66 espécies de foraminíferos bentônicos, sendo 36 espécies aglutinantes e 30 espécies calcárias. As espécies mais freqüentes foram as calcárias Bolivina pseudopunctata, Cassidulinoides parkerianus e Globocassidulina biora, e as aglutinantes Portatrochammina antarctica, Pseudobolivina antarctica e Spiroplectammina biformis. As espécies Portatrochammina antarctica e Pseudobolivina antarctica foram as mais abundantes na porção central e em algumas estações das três enseadas da baía. As regiões mais internas das enseadas apresentaram predominância de espécies hialinas principalmente do gênero Globocassidulina e Cassidulinoides. A predominância de espécies hialinas também foi observada nas estações próximas a desembocadura da Baía do Almirantado com as espécies Bolivina pseudopunctata e Fursenkoina fusiformis. / The Antarctic region is focus of constant scientific surveys because of its importance as global climate changing area. The marine bottom sediment has an associated biota that indicates some environmental changes and among them Foraminifera could be considered as one of the best marine biomarkers. The aim of the present study is describe the recent benthic foraminifera fauna from Admiralty Bay collected during three consecutive austral summers (2002/2003, 2003/2004 and 2004/2005) and better understand its ecology and distribution patterns throughout the bay and its relations with some environmental factors. Fifty-six bottom sediment samples were collected along the Admiralty Bay for analysis and identification of the forams fauna and abiotic factors from sediment and bottom water. We found 66 species of benthic foraminifera, 36 agglutinated and 30 calcareous. The most frequent species were the calcareous Bolivina pseudopunctata, Cassidulinoides parkerianus and Globocassidulina biora, and the agglutinated Portatrochammina antarctica, Pseudobolivina antarctica and Spiroplectammina biformis. The species Portatrochammina antarctica and Pseudobolivina antarctica were the most abundant in the central portion of the bay and in some samples of the three inlets of the bay. The inner parts of the inlets there was a predominance of calcareous such as Globocassidulina spp. and Cassidulinoides spp.. The predominance of calcareous species, such as Bolivina pseudopunctata and Fursenkoina fusiformis was also observed at samples near the connection between the Admiralty Bay and the Bransfield Strait.
167

Architecture of human complex trait variation

Xin, Xiachi January 2018 (has links)
A complex trait is a trait or disease that is controlled by both genetic and environmental factors, along with their interactions. Trait architecture encompasses the genetic variants and environmental causes of variation in the trait or disease, their effects on the trait or disease and the mechanism by which these factors interact at molecular and organism levels. It is important to understand trait architecture both from a biological viewpoint and a health perspective. In this thesis, I laid emphasis on exploring the influence of familial environmental factors on complex trait architecture alongside the genetic components. I performed a variety of studies to explore the architecture of anthropometric and cardio-metabolic traits, such as height, body mass index, high density lipoprotein content of blood and blood pressure, using a cohort of 20,000 individuals of recent Scottish descent and their phenotype measurements, Single Nucleotide Polymorphism (SNP) data and genealogical information. I extended a method of variance component analysis that could simultaneously estimate SNP-associated heritability and total heritability whilst considering familial environmental effects shared among siblings, couples and nuclear family members. I found that most missing heritability could be explained by including closely related individuals in the analysis and accounting for these close relationships; and that, on top of genetics, couple and sibling environmental effects are additional significant contributors to the complex trait variation investigated. Subsequently, I accounted for couple and sibling environmental effects in Genome- Wide Association Study (GWAS) and prediction models. Results demonstrated that by adding additional couple and sibling information, both GWAS performance and prediction accuracy were boosted for most traits investigated, especially for traits related to obesity. Since couple environmental effects as modelled in my study might, in fact, reflect the combined effect of assortative mating and shared couple environment, I explored further the dissection of couple effects according to their origin. I extended assortative mating theory by deriving the expected resemblance between an individual and in-laws of his first-degree relatives. Using the expected resemblance derived, I developed a novel pedigree study which could jointly estimate the heritability and the degree of assortative mating. I have shown in this thesis that, for anthropometric and cardio-metabolic traits, environmental factors shared by siblings and couples seem to have important effects on trait variation and that appropriate modelling of such effects may improve the outcome of genetic analyses and our understanding of the causes of trait variation. My thesis also points out that future studies on exploring trait architecture should not be limited to genetics because environment, as well as mate choice, might be a major contributor to trait variation, although trait architecture varies from trait to trait.
168

Comparative analysis of organ size, shape, and patterning in diverse species

Siomava, Natalia 21 December 2016 (has links)
No description available.
169

Estudo das associações de foraminíferos bentônicos recentes na Baía do Almirantado (Ilha Rei George, Antártica) durante três verões austrais consecutivos / Study of the recent benthic Foraminifera assemblages from Admiralty Bay (King George Island, Antartica) during three consecutive austral summers

André Rosch Rodrigues 19 August 2008 (has links)
A região antártica é foco de constante observação por ser uma região de importante monitoramento climático global. Ao sedimento de fundo marinho está associada uma biota que responde aos processos de alterações ambientais e dentre seus representantes os foraminíferos são considerados bons indicadores marinhos. O objetivo do presente estudo é avaliar a fauna de foraminíferos recentes na Baía do Almirantado durante três verões austral consecutivos (2002/2003, 2003/2004 e 2004/2005) e, através da determinação de algumas variáveis ambientais, compreender melhor a ecologia e a distribuição desses organismos na região. Foram coletadas 56 amostras de sedimento de fundo marinho ao longo da Baía do Almirantado para análise e identificação da fauna de foraminíferos e de variáveis abióticas amostradas na água de fundo e no sedimento. Foram encontradas 66 espécies de foraminíferos bentônicos, sendo 36 espécies aglutinantes e 30 espécies calcárias. As espécies mais freqüentes foram as calcárias Bolivina pseudopunctata, Cassidulinoides parkerianus e Globocassidulina biora, e as aglutinantes Portatrochammina antarctica, Pseudobolivina antarctica e Spiroplectammina biformis. As espécies Portatrochammina antarctica e Pseudobolivina antarctica foram as mais abundantes na porção central e em algumas estações das três enseadas da baía. As regiões mais internas das enseadas apresentaram predominância de espécies hialinas principalmente do gênero Globocassidulina e Cassidulinoides. A predominância de espécies hialinas também foi observada nas estações próximas a desembocadura da Baía do Almirantado com as espécies Bolivina pseudopunctata e Fursenkoina fusiformis. / The Antarctic region is focus of constant scientific surveys because of its importance as global climate changing area. The marine bottom sediment has an associated biota that indicates some environmental changes and among them Foraminifera could be considered as one of the best marine biomarkers. The aim of the present study is describe the recent benthic foraminifera fauna from Admiralty Bay collected during three consecutive austral summers (2002/2003, 2003/2004 and 2004/2005) and better understand its ecology and distribution patterns throughout the bay and its relations with some environmental factors. Fifty-six bottom sediment samples were collected along the Admiralty Bay for analysis and identification of the forams fauna and abiotic factors from sediment and bottom water. We found 66 species of benthic foraminifera, 36 agglutinated and 30 calcareous. The most frequent species were the calcareous Bolivina pseudopunctata, Cassidulinoides parkerianus and Globocassidulina biora, and the agglutinated Portatrochammina antarctica, Pseudobolivina antarctica and Spiroplectammina biformis. The species Portatrochammina antarctica and Pseudobolivina antarctica were the most abundant in the central portion of the bay and in some samples of the three inlets of the bay. The inner parts of the inlets there was a predominance of calcareous such as Globocassidulina spp. and Cassidulinoides spp.. The predominance of calcareous species, such as Bolivina pseudopunctata and Fursenkoina fusiformis was also observed at samples near the connection between the Admiralty Bay and the Bransfield Strait.
170

Development and evaluation of automated radar systems for monitoring and characterising echoes from insect targets

Dean, Timothy J., Physical, Environmental & Mathematical Sciences, Australian Defence Force Academy, UNSW January 2007 (has links)
This thesis describes the construction of a mobile Insect Monitoring Radars (IMR) and investigations of: the reliability of IMRs for observing insect migration in inland Australia; possible biases in IMR migration estimates; the relation between an insect???s size and its radar properties; radar discrimination between insect species; the effect of weather on the migrations of Australian plague locusts and of moths; the scale of these migrations; and here IMRs are best located. The principles of entomological radar design, and the main features of insect migration in inland Australia, are reviewed. The main procedures used in the study are: calculation of radar performance and of insect radar cross sections (RCSs); reanalysis of a laboratory RCS dataset; statistical analysis of a fouryear dataset of IMR and weather observations; and a field campaign using both two existing fixed IMRs and the new mobile unit. Statistical techniques used include correlation, multiple regression, discriminant analysis, and principal components analysis. The original results of this work include design details of the mobile IMR, extension of radar performance calculations to IMRs and evaluation of flight speed biases, a holistic approach to IMR design, the relation of insect RCS magnitudes and polarization patterns to morphological variables, an estimate of the accuracy of the retrieved parameters, evaluations of three approaches (oneparameter, theory-based, and a novel two-stage method) to target identification, and verification of inferred target identities using results from nearby light traps. Possible sites for future IMRs are identified. The major conclusions are that: a mobile IMR can be built with a performance equal to that of a fixed IMR but at half the cost; significant biases in the signal processing results arise from insect speed; locusts and moths can be distinguished if all RCS parameters are used; IMRs can be designed to match particular requirements; weather has a significant effect on insect migration, the best single predictor of insect numbers being temperature; moonlight has no effect; the spatial correlation of migration properties falls to 50% at a separation of 300 km; and migrating insects can be carried by the wind for 500 km in a single night

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