916 resultados para over-generalization and under-generalization problems
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The Pierre Auger Cosmic Ray Observatory North site employs a large array of surface detector stations (tanks) to detect the secondary particle showers generated by ultra-high energy cosmic rays. Due to the rare nature of ultra-high energy cosmic rays, it is important to have a high reliability on tank communications, ensuring no valuable data is lost. The Auger North site employs a peer-to-peer paradigm, the Wireless Architecture for Hard Real-Time Embedded Networks (WAHREN), designed specifically for highly reliable message delivery over fixed networks, under hard real-time deadlines. The WAHREN design included two retransmission protocols, Micro- and Macro- retransmission. To fully understand how each retransmission protocol increased the reliability of communications, this analysis evaluated the system without using either retransmission protocol (Case-0), both Micro- and Macro-retransmission individually (Micro and Macro), and Micro- and Macro-retransmission combined. This thesis used a multimodal modeling methodology to prove that a performance and reliability analysis of WAHREN was possible, and provided the results of the analysis. A multimodal approach was necessary because these processes were driven by different mathematical models. The results from this analysis can be used as a framework for making design decisions for the Auger North communication system.
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Carbon Monoxide (CO) and Ozone (O3) are considered to be one of the most important atmospheric pollutants in the troposphere with both having significant effects on human health. Both are included in the U.S. E.P.A list of criteria pollutants. CO is primarily emitted in the source region whereas O3 can be formed near the source, during transport of the pollution plumes containing O3 precursors or in a receptor region as the plumes subside. The long chemical lifetimes of both CO and O3 enable them to be transported over long distances. This transport is important on continental scales as well, commonly referred to as inter-continental transport and affects the concentrations of both CO and O3 in downwind receptor regions, thereby having significant implications for their air quality standards. Over the period 2001-2011, there have been decreases in the anthropogenic emissions of CO and NOx in North America and Europe whereas the emissions over Asia have increased. How these emission trends have affected concentrations at remote sites located downwind of these continents is an important question. The PICO-NARE observatory located on the Pico Mountain in Azores, Portugal is frequently impacted by North American pollution outflow (both anthropogenic and biomass burning) and is a unique site to investigate long range transport from North America. This study uses in-situ observations of CO and O3 for the period 2001-2011 at PICO-NARE coupled with output from the full chemistry (with normal and fixed anthropogenic emissions) and tagged CO simulations in GEOS-Chem, a global 3-D chemical transport model of atmospheric composition driven by meteorological input from the Goddard Earth Observing System (GEOS) of the NASA Global Modeling and Assimilation Office, to determine and interpret the trends in CO and O3 concentrations over the past decade. These trends would be useful in ascertaining the impacts emission reductions in the United States have had over Pico and in general over the North Atlantic. A regression model with sinusoidal functions and a linear trend term was fit to the in-situ observations and the GEOS-Chem output for CO and O3 at Pico respectively. The regression model yielded decreasing trends for CO and O3 with the observations (-0.314 ppbv/year & -0.208 ppbv/year respectively) and the full chemistry simulation with normal emissions (-0.343 ppbv/year & -0.526 ppbv/year respectively). Based on analysis of the results from the full chemistry simulation with fixed anthropogenic emissions and the tagged CO simulation it was concluded that the decreasing trends in CO were a consequence of the anthropogenic emission changes in regions such as USA and Asia. The emission reductions in USA are countered by Asian increases but the former have a greater impact resulting in decreasing trends for CO at PICO-NARE. For O3 however, it is the increase in water vapor content (which increases O3 destruction) along the pathways of transport from North America to PICO-NARE as well as around the site that has resulted in decreasing trends over this period. This decrease is offset by increase in O3 concentrations due to anthropogenic influence which could be due to increasing Asian emissions of O3 precursors as these emissions have decreased over the US. However, the anthropogenic influence does not change the final direction of the trend. It can thus be concluded that CO and O3 concentrations at PICO-NARE have decreased over 2001-2011.
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Empirical research has shown that pubertal development is closely linked with adolescent externalizing (e.g., aggressive) and internalizing (e.g., anxiety) problems. In most studies, pubertal timing, pubertal status, or both, are used to examine this link. The present study adds to the existing literature by examining the link between puberty and adolescent behavior problems in a sample of predominantly urban African American adolescent girls. One hundred and seventeen adolescent girls of color, aged 11-18 (M = 14.72 SD = 1.44), and their primary caregiver participated in this study. Sixty-eight percent were African American, 22.2 % were Hispanic/Latina, and 9.4% were Haitian. Among the Hispanic/Latina girls, 9.4% were Black Hispanic/Latina. Results showed that pubertal status and perceived pubertal timing (breasts) are better predictors of externalizing behavior problems than chronological age and quality of relationship with peers. No significant findings were found with anxious/depressed symptoms.
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We consider the Cauchy problem for the Laplace equation in 3-dimensional doubly-connected domains, that is the reconstruction of a harmonic function from knowledge of the function values and normal derivative on the outer of two closed boundary surfaces. We employ the alternating iterative method, which is a regularizing procedure for the stable determination of the solution. In each iteration step, mixed boundary value problems are solved. The solution to each mixed problem is represented as a sum of two single-layer potentials giving two unknown densities (one for each of the two boundary surfaces) to determine; matching the given boundary data gives a system of boundary integral equations to be solved for the densities. For the discretisation, Weinert's method [24] is employed, which generates a Galerkin-type procedure for the numerical solution via rewriting the boundary integrals over the unit sphere and expanding the densities in terms of spherical harmonics. Numerical results are included as well.
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This thesis examines deindustrialisation, the declining contribution of industrial activities to economic output and employment, in Lanarkshire, Scotland’s largest coalfield between the early nineteenth and mid-twentieth century. It focuses on contraction between the National Coal Board’s (NCB) vesting in 1947 and the closure of Lanarkshire’s last colliery, Cardowan, in 1983. Deindustrialisation was not the natural outcome of either market forces or geological exhaustion. Colliery closures and falling coal employment were the result of policy-makers’ decisions. The thesis consists of four thematic chapters: political economy, moral economy, class and community, and generation and gender. The analysis is based on archival sources including Scottish Office reports and correspondence relating to regional policy, and NCB records. These are supported by National Union of Mineworkers Scottish Area and STUC meeting minutes, and oral history testimonies from over 30 men and women with Lanarkshire coalfield backgrounds, as well as two focus groups. The first two chapters analyse the process of deindustrialisation, with the first offering a top-down perspective and the second a bottom-up viewpoint. In chapter one deindustrialisation is analysed through changes in political economy. Shifts in labour market structure are examined through the development of regional policy and its administration by the Scottish Office. The analysis centres upon a policy network of Scottish business elites and civil servants who shaped a vision of modernisation via industrial diversification through attracting inward investment. In chapter two the perspective shifts to community and workforce. It analyses responses to coalfield contraction through a moral economy of customary rights to colliery employment. A detailed investigation of Lanarkshire colliery closures between the 1940s and 1980s emphasises the protracted nature of deindustrialisation. Chapters three and four consider the social and cultural structures which shaped the moral economy but were heavily altered by deindustrialisation. Chapter three focuses on the dense networks that linked occupation, community, and class consciousness. Increasing coalfield centralisation and remote control of pits from NCB headquarters in London, and mounting hostility to coal closures, contributed to an accentuated sense of Scottish-ness. Chapter four illuminates gender and generational dimensions. The differing experiences of cohorts of men who faced either early retirement, redundancy or transfer to alternative sectors, or those who never attained anticipated industrial employment due to final closures, are analysed in terms of constructions of masculinity and the endurance of cultural as well as material losses. This is counterpoised to women who gained industrial work in assembly plants and the perceived gradual attainment of an improved economic and social position whilst continuing to navigate structures of patriarchy.
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Understanding confinement and its complex workings between individuals and society has been the stated aim of carceral geography and wider studies on detention. This project contributes ethnographic insights from multiple sites of incarceration, working with an under-researched group within confined populations. Focussing on young female detainees in Scotland, this project seeks to understand their experiences of different types of ‘closed’ space. Secure care, prison and closed psychiatric facilities all impact on the complex geographies of these young women’s lives. The fluid but always situated relations of control and care provide the backdrop for their journeys in/out and beyond institutional spaces. Understanding institutional journeys with reference to age and gender allows an insight into the highly mobile, often precarious, and unfamiliar lives of these young women who live on the margins. This thesis employs a mixed-method qualitative approach and explores what Goffman calls the ‘tissue and fabric’ of detention as a complex multi-institutional practice. In order to be able to understand the young women’s gendered, emotional and often repetitive experiences of confinement, analysis of the constitution of ‘closed space’ represents a first step for inquiry. The underlying nature of inner regimes, rules and discipline in closed spaces, provide the background on which confinement is lived, perceived and processed. The second part of the analysis is the exploration of individual experiences ‘on the inside’, ranging from young women’s views on entering a closed institution, the ways in which they adapt or resist the regime, and how they cope with embodied aspects of detention. The third and final step considers the wider context of incarceration by recovering the young women’s journeys through different types of institutional spaces and beyond. The exploration of these journeys challenges and re-develops understandings of mobility and inertia by engaging the relative power of carceral archipelagos and the figure of femina sacra. This project sits comfortably within the field of carceral geography while also pushing at its boundaries. On a conceptual level, a re-engagement with Goffman’s micro-analysis challenges current carceral-geographic theory development. Perhaps more importantly, this project pushes for an engagement with different institutions under the umbrella of carceral geography, thus creating new dialogues on issues like ‘care’ and ‘control’. Finally, an engagement with young women addresses an under-represented population within carceral geography in ways that raise distinctly problematic concerns for academic research and penal policy. Overall, this project aims to show the value of fine grained micro-level research in institutional geographies for extending thinking and understanding about society’s responses to a group of people who live on the margins of social and legal norms.
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The aim of the present work is to gain new insights into the formation mechanism of CdTe magic-sized clusters (MSCs) at low temperatures, as well as on their evolution towards 1D and 2D nanostructures and assemblies thereof, under mild reaction conditions. The reaction system included toluene as solvent, octylamine as primary alkylamine, trioctylphosphine-Te as chalcogenide precursor and Cd(oleate)2 as metal precursor. UV-Vis absorption spectroscopy and transmission electron microscopy (TEM) were used to analyze samples containing concentrations of octylamine of 0.2, 0.8 and 2 M: well-defined, sharp absorption peaks were observed, with peaks maxima at 449, 417 and 373 nm respectively, and 1D structures with a string-like appearance were displayed in the TEM images. Investigating peaks growth, step-wise peaks shift to lower energies and reverse, step-wise peak shift to higher energies allowed to propose a model to describe the system, based on interconnected [CdTe]x cluster units originating an amine-capped, 1-dimensional, polymer-like structure, in which different degrees of electronic coupling between the clusters are held responsible for the different absorption transitions. The many parameters involved in the synthesis procedure were then investigated, starting from the Cd:Te ratio, the role of the amine, the use of different phosphine-Te and Cd precursors. The results allowed to gain important information of the reaction mechanism, as well as on the different behavior of the species featuring the sharp absorption peaks in each case. Using Cd(acetate)2 as metal precursor, 2D structures were found to evolve from the MSCs solutions over time, and their tendency to self-assemble was then analyzed employing two amines of different alkyl chain length, octylamine (C-8) and oleylamine (C-18). Their co-presence led to the formation of free-floating triangular nanosheets, which tend to readily aggregate if only octylamine is present in solution.
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Modern scientific discoveries are driven by an unsatisfiable demand for computational resources. High-Performance Computing (HPC) systems are an aggregation of computing power to deliver considerably higher performance than one typical desktop computer can provide, to solve large problems in science, engineering, or business. An HPC room in the datacenter is a complex controlled environment that hosts thousands of computing nodes that consume electrical power in the range of megawatts, which gets completely transformed into heat. Although a datacenter contains sophisticated cooling systems, our studies indicate quantitative evidence of thermal bottlenecks in real-life production workload, showing the presence of significant spatial and temporal thermal and power heterogeneity. Therefore minor thermal issues/anomalies can potentially start a chain of events that leads to an unbalance between the amount of heat generated by the computing nodes and the heat removed by the cooling system originating thermal hazards. Although thermal anomalies are rare events, anomaly detection/prediction in time is vital to avoid IT and facility equipment damage and outage of the datacenter, with severe societal and business losses. For this reason, automated approaches to detect thermal anomalies in datacenters have considerable potential. This thesis analyzed and characterized the power and thermal characteristics of a Tier0 datacenter (CINECA) during production and under abnormal thermal conditions. Then, a Deep Learning (DL)-powered thermal hazard prediction framework is proposed. The proposed models are validated against real thermal hazard events reported for the studied HPC cluster while in production. This thesis is the first empirical study of thermal anomaly detection and prediction techniques of a real large-scale HPC system to the best of my knowledge. For this thesis, I used a large-scale dataset, monitoring data of tens of thousands of sensors for around 24 months with a data collection rate of around 20 seconds.
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Part 1 of the study aims to: evaluate NGF and VEGF levels obtained at parturition from mare, foal and umbilical cord vein plasma, as well as in amniotic fluid; evaluate NGF and VEGF content in plasma of healthy foals during the first 72 h of life; evaluate NGF and VEGF levels at parturition in relation to selected mares’ and foals’ clinical parameters; evaluate the relationship between the two trophic factors and thyroid hormone levels in the first 72 h of life; assess mRNA expression of NGF, VEGF and BDNF and their cell surface receptors in the placenta. Part 2 aims to clinically characterize a population of foals spontaneously affected by Neonatal Encephalopathy (NE), and then to: evaluate NGF and VEGF levels in plasma samples obtained in the affected population at parturition from mare’s jugular vein, umbilical cord vein and foal’s jugular vein, as well as in amniotic fluid; evaluate NGF and VEGF content in plasma of foals affected by NE during the first 72 h of life/hospitalization; evaluate NGF and VEGF levels at birth/admission in relation to selected mares’ and foals’ clinical parameters; evaluate the relationship between the two trophic factors and thyroid hormone levels in the first 72 h of life/hospitalization; assess the mRNA expression of NGF, VEGF and BDNF, and their cell surface receptors, in the placenta of mares that delivered affected foals. The close relationship between the two trophic factors in foal plasma over time and their fine expression in placental tissues under physiological conditions appear to be key regulators of fetal development and adaptation. Their less pronounced decrease in compromised foals compared to healthy ones, their relationship with thyroid hormones over time, and the reduced expression of NGF and BDNF in placental tissues, could be key regulators in the mechanisms of NE.
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Universidade Estadual de Campinas . Faculdade de Educação Física
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The objective of the present study was to evaluate the effects of light and temperature on germination of Cereus pernambucensis seeds, a species of columnar cactus native to Brazil and naturally incident in the restinga. Cereus pernambucensis seeds were incubated under different temperatures, from 5 to 45 °C, with 5 °C intervals, and under alternating temperatures of 15-20 °C, 15-30 °C, 20-25 °C, 20-30 °C, 20-35 °C, 25-30 °C, 25-35 °C, and 30-35 °C, both under continuous white light and dark. The seeds were also incubated in a gradient of phytochrome photoequilibrium at 25 °C. The highest percentage germination in this species was between 25 and 30 °C. The minimum temperature was between 15 and 20 °C and the maximum between 35 and 40 °C. Alternating temperatures did not affect the percentage of seed germination, but it did alter the rate and synchronization indexes. Seeds incubated in the dark did not germinate under any of the conditions tested, indicating that this species when cultivated present light sensitive seeds controlled by phytochrome. The seeds can tolerate a lot of shade conditions, germinating under very low fluence response of phytochrome.
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OBJETIVOS: Este trabalho estuda a distribuição dos óbitos por causas mal definidas no Brasil, no ano de 2003, entre as quais identifica a proporção de mortes sem assistência. MÉTODOS: Os dados provieram do Sistema de Informações Sobre Mortalidade, coordenado pelo Ministério da Saúde. As causas mal definidas de morte compreenderam as incluídas no "Capítulo XVIII - Sintomas, sinais e achados anormais de exames clínicos e de laboratório não classificados em outra parte" da Classificação Estatística Internacional de Doenças e Problemas Relacionados à Saúde, décima revisão, capítulo este no qual a categoria R98 identificava a "morte sem assistência". RESULTADOS: No Brasil, em 2003, a causa básica de 13,3% dos óbitos foi identificada como mal definida, sendo que as proporções maiores ocorreram nas Regiões Nordeste e Norte. Do total de causas mal definidas no país, 53,3% corresponderam a mortes sem assistência, proporção esta que superou 70% nos Estados do Maranhão, Piauí, Rio Grande do Norte, Pernambuco, Bahia, Paraíba e Alagoas. CONCLUSÃO: Dada a estrutura descentralizada para o levantamento dos óbitos no país, identifica-se a maior responsabilidade dos municípios e, em seguida, dos Estados para o aprimoramento da qualidade das estatísticas de mortalidade.
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OBJETIVO: Verificar a validade do Questionário de Freqüência Alimentar para Adolescentes para avaliar o consumo de grupos de alimentos entre escolares de Piracicaba, São Paulo. MÉTODOS: Participaram do estudo 94 adolescentes, com idade entre 11 e 15 anos, matriculados em uma escola da rede pública. O consumo alimentar foi avaliado pelo Questionário de Freqüência Alimentar para Adolescentes (QFAA) e a média de dois Recordatórios de 24 horas (R24h) foi utilizada como método de referência. Os itens alimentares foram classificados em 18 grupos. Foram realizadas análises descritivas, teste t-Student pareado e de Wilcoxon, coeficientes de correlação de Pearson e de Spearman. Foram também utilizadas análise de quartis e estatística Kappa ponderado. Os coeficientes de correlação foram corrigidos pela variância intrapessoal dos R24h, estimada a partir de ANOVA com um fator de classificação. RESULTADOS: Não foram verificadas diferenças significativas entre os instrumentos para o arroz, massas, carnes, refrigerantes e sucos artificiais. Os coeficientes de correlação corrigidos pela variabilidade intrapessoal variaram de -0,26 a 0,78. A concordância de classificação dos indivíduos no mesmo quartil de consumo para ambos os métodos variou de 22% (massas) a 50% (feijão). Para quartis opostos, os grupos que tiveram mais de 10% dos indivíduos classificados incorretamente foram massas (19%), carnes (13%) e gorduras (11%). Os valores de Kappa ponderado variaram de - 0,15 (massas) a 0,56 (feijão). O QFAA superestimou o consumo de quase a totalidade dos grupos alimentares e subestimou os grupos dos óleos, feijão, carnes e refrigerantes. CONCLUSÃO: O instrumento apresentou boa validade para feijão, verduras e legumes, leite e derivados, biscoitos recheados e para o arroz.
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OBJETIVO: Avaliar a associação entre eventos de vida produtores de estresse (EVPE) e queixas de insônia (QI). MÉTODOS: Foram analisados dados seccionais de 695 auxiliares de enfermagem de um hospital universitário, participantes do Estudo Pró-Saúde - coorte de funcionários de uma universidade no Rio de Janeiro. As informações foram obtidas através de um questionário multidimensional e autopreenchido, que avaliou a ocorrência de EVPE nos últimos 12 meses, variáveis socioeconômicas e demográficas e QI. As QI foram analisadas como desfecho politômico (frequente, ocasional, e ausente). Odds ratios brutos e ajustados foram calculados através de regressão logística multinomial. RESULTADOS: A prevalência total de QI foi de 45,8% (16,7% frequentes e 29,1% ocasionais). Após ajuste por sexo, idade, estado civil, renda familiar per capita e regime de trabalho, os EVPE associados com QI frequentes foram: "rompimento de relação amorosa" (OR = 3,32; IC95% 1,90 - 5,78), "ter tido problemas graves de saúde" (OR = 2,82; IC95% 1,73 - 4,58); "dificuldades financeiras graves" (OR = 2,38; IC95% 1,46 - 3,88), e "mudança forçada de moradia" (OR = 1,97; IC95% 1,02 - 3,79). Com relação às QI ocasionais, houve associação apenas com rompimento de relação amorosa (OR = 2,30; IC95% 1,42 - 3,74) e dificuldades financeiras graves (OR = 1,87; IC95% 1,27 - 2,75). CONCLUSÕES: Dada a responsabilidade com vidas humanas que os auxiliares de enfermagem assumem durante seu horário de trabalho, nossos achados podem contribuir para ações mais efetivas, por parte dos serviços de saúde ao trabalhador, para lidar com o estresse nessa categoria
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Pathogenicity of strains of the entomopathogenic fungus Beauveria bassiana and endophytic strains of Beauveria sp against the bovine tick Rhipicephalus (Boophilus) microplus was tested in laboratory bioassays and under field conditions. Suspensions containing 10(5), 10(7) and 10(9) conidia/mL were prepared of each fungal strain for laboratory bioassays. The ticks were maintained at 28 degrees C, 90 +/- 5% relative humidity, and the following variables were evaluated: initial female weight, egg weight, hatching percentage, reproductive efficiency, and percentage control. For tests under field conditions, a Beauveria suspension containing 10(6) conidia/mL was sprayed on tick-infested cows. After 72 h, the ticks were collected to estimate mortality under field conditions. Laboratory bioassays showed a mortality of 20 to 50% of the ticks seven days after inoculation with 10(7) Beauveria conidia/mL. Under field conditions 10(6) Beauveria conidia/mL induced 18-32% mortality. All Beauveria strains were effective in biological control of R. (Boophilus) microplus under laboratory and field test conditions. This is the first demonstration that endophytic fungi can be used for biological control of the cattle tick; this could help reduce environmental contamination by diminishing the need for chemical acaricides. Two endophytic strains were isolated from maize leaves and characterized by molecular sequencing of 5.8S rDNA ITS1 and ITS2 and morphological analyses of conidia. We found that these two endophytic Beauveria isolates, designated B95 and B157, are close to Beauveria amorpha.