As a result of the rise in processing power demands of today’s personal computers, water cooled pin fin heat sinks are increasingly being employed for the cooling of graphical processing units. Currently, these high performance devices are manufactured through high-cost, high-waste processes. In recent years, a new solution has emerged using the cold gas dynamic spray process, in which pin fins are directly manufactured onto a baseplate by spraying metallic powder particles through a mask. This process allows for a high degree of adaptability to different graphics processing unit shapes and sizes not achievable by any other process to date. One drawback of this process is that, as substrate sensitivity to heat and mechanical residual stresses requires the use of reduced spray parameters, there is reduced deposition efficiency, resulting in a fair portion of the feedstock powder being wasted. This work aims to demonstrate the feasibility of using powder recycling to mitigate this issue and compares coatings sprayed with reclaimed powder to their counterparts sprayed with as-received powder. The work demonstrates that cold gas dynamic spray is a highly flexible and economically competitive process for the production of pin fin heat sinks when using powder recycling even when spray parameters result in reduced deposition efficiency. The benefits of pin fins on heat transfer properties of flat plates used for graphical processing units is briefly addressed and demonstrated

Made available in DSpace on 2014-06-11T19:25:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-02Bitstream added on 2014-06-13T20:32:47Z : No. of bitstreams: 1 vergilio_sal_me_ilha.pdf: 3337665 bytes, checksum: 50e13409fecfd3249ea5cb1d7e6b9c79 (MD5) / Este trabalho trata da análise dos tipos de ligações usualmente empregadas em trelliças de cobertura constituídas por perfís de aço formados a frio. O escopo da análise engloba seu comportamento estrutural e modelos de cálculo. Além disso, apresenta e comenta os procedimentos indicados na norma brasileira NBR 14762:2010 Dimensionamento de estruturas de aço constituídas por perfís formado a frio (ABNT - ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS),pela NBR 8800:2008 Projeto de estruturas de aço e estruturas mistas de aço e concreto de edifícios - quando referidos pela primeira - e também por reconhecidas normas estrangeiras. Os meios de ligação estudados são parafusos e soldas; os elementos da ligação são as barras, cobrejuntas, chapas de gusset entre outros. As barras pertencentes às treliças são de perfís U ou L e suas combinações. Cada tipo de ligação de barra estudada apresenta as respectivas planilhas eletrônicas... / This work deals with the analysis of connections types commonly used in roof trusses consisting of steel cold-formed profiles. The scope of review includes its structural behavior and calculation models. it also presents and discusses the procedures specified by recognized foreign standards, the Brazilian Standard for cold-formed steel, and welded connections are studied; the connection elements are the bars, joint sheeting and gusset plates, among others... (Complete abstract click electronic access below)

Master of Science / Department of Civil Engineering / Hani Melhem / The combination of cold formed steel (CFS) with structural wood panels exhibits a degree of partial composite action behavior. In the current design and construction codes, CFS and wood sheathing systems are considered separate, in a non-composite manner, due to the absence of sufficient supporting experimental and research data. The problem with previous research is the lack of information to fully define the composite action between CFS and wood sheathing. The scope of this study is to check fundamental information provided in previous research. The approach adopted to solve the problem follows previous experimental procedures conducted at Kansas State University. The objective of the research is to determine the slip modulus with various fastener spacing. Additional results obtained in this study are compared to previous research results.

Orientador: Renato Bertolino Junior / Banca: José Antônio Matthiesen / Banca: João Alberto Venegas Requena / Resumo: Este trabalho trata da análise dos tipos de ligações usualmente empregadas em trelliças de cobertura constituídas por perfís de aço formados a frio. O escopo da análise engloba seu comportamento estrutural e modelos de cálculo. Além disso, apresenta e comenta os procedimentos indicados na norma brasileira NBR 14762:2010 "Dimensionamento de estruturas de aço constituídas por perfís formado a frio" (ABNT - ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS),pela NBR 8800:2008 "Projeto de estruturas de aço e estruturas mistas de aço e concreto de edifícios" - quando referidos pela primeira - e também por reconhecidas normas estrangeiras. Os meios de ligação estudados são parafusos e soldas; os elementos da ligação são as barras, cobrejuntas, chapas de gusset entre outros. As barras pertencentes às treliças são de perfís "U" ou "L" e suas combinações. Cada tipo de ligação de barra estudada apresenta as respectivas planilhas eletrônicas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work deals with the analysis of connections types commonly used in roof trusses consisting of steel cold-formed profiles. The scope of review includes its structural behavior and calculation models. it also presents and discusses the procedures specified by recognized foreign standards, the Brazilian Standard for cold-formed steel, and welded connections are studied; the connection elements are the bars, joint sheeting and gusset plates, among others... (Complete abstract click electronic access below) / Mestre

abstract: Background: Research in animal models suggests that fish oil ingestion may impair immunity and increase risk for infection. To date there are no studies examining this relationship between fish oil ingestion and risk for infection in humans. Objective: The primary aim of this randomized, placebo-controlled, double-blind, parallel-arm study was to examine the effect of 400 mg of EPA and 200 mg of DHA, the main components of fish oil (FO) supplements, on the incidence of symptoms related to upper respiratory tract infections in healthy young females, at a large southwestern university. Design: Healthy young women between 18 and 38 years of age who were non-obese (mean BMI 23.7 ± 0.6 kg/m2) were recruited from an urban southwestern university campus. Subjects were non-vegetarians, non-smokers, and reported consuming less than one serving (3.5 oz) of fish per week. Participants (n=26) were randomized according to age, body weight, BMI, and daily n-3 fatty acid (FA) intake into two groups: FO (one gel capsule of 600 mg EPA/DHA per day) or CO (one placebo gel capsule of 1000 mg coconut oil per day). Participants completed a validated daily cold symptom survey, the Wisconsin Upper Respiratory Symptom Survey-21 for 8 weeks. Fasting blood samples measuring TNF-α concentrations were taken at weeks 1 and 8, when 24-hour dietary recalls were also performed. Anthropometric measurements were recorded via bioelectrical impedance at trial weeks 1, 4, and 8. Results: The 8-week trial of FO supplementation did not significantly change the average score for perception of cold symptoms between FO and CO groups (167 ± 71 and 185 ± 56, p=0.418, respectively). Plasma TNF-α levels (pg/mL) did not differ between groups (p=0.482). TNF-α levels were significantly correlated with body weight (r=0.480, p=0.037), BMI (r=0.481, p=0.037, and percent body fat (r=0.511, p=0.025) at baseline. Conclusions: Healthy young women taking a fish oil supplement of 400 mg EPA and 200 mg DHA per day over 8 weeks does not impose unintentional health consequences. These findings do not refute the American Heart Association's current recommendations for all Americans to consume two servings (3.5 oz) of a variety of oily fish per week. Depending on the type of fish, this current recommendation equates to approximately 200-300 mg per day of EPA and DHA n-3 polyunsaturated fatty acids. Additional research is needed to investigate the effects of higher dosages of fish oils on daily cold symptoms. / Dissertation/Thesis / M.S. Nutrition 2013

Este trabalho consiste basicamente em dois experimentos: Determinação da equação de estado de um gás frio aprisionado, e na comparação das temperaturas de uma amostra de átomos confinadas em dois tipos de armadilhas magneto-ópticas. No primeiro experimento utilizamos a generalização do conceito de pressão e volume que foram redefinidos de maneira apropriada para alcançamos uma equação de estado. Experimentalmente nossa amostra apresentou um desvio do esperado para um gás ideal, dessa forma utilizamos uma expansão virial com as novas definições de pressão e volume para investigar as interações entre os átomos. Já no segundo experimento utilizamos uma técnica que mede transiente temporal da absorção do feixe pelos átomos através de um fotodetector para a obtenção da temperatura. Neste experimento obtemos temperaturas equivalentes para as duas armadilhas. / This work consists of two experiments: Determination of the state equation a trapped cold gas, and the comparison of the temperatures of confined atoms in two types of magneto-optical traps. For the first experiment we generalized and defined a new pressure and volume concept and we reached a state equation. Experimentally our sample presented a deviation of the ideal gas, in that way we used a virial expansion with the new pressure and volume definitions to investigate the interactions among the atoms. In the second experiment we used a technique that measures temporal variation of the absorption of a probe beam that crosses the atoms by a photodetector, witch gives us the information about the temperature. We have found equivalent temperatures for the two traps.

Orientador: Paulo Mazzafera / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-11T01:13:03Z (GMT). No. of bitstreams: 1 Sobczak_JullyanaCristinaMagalhaesSilvaMoura_M.pdf: 2446892 bytes, checksum: 4c97412103a3d5abdab642b94a070f35 (MD5) Previous issue date: 2008 / Resumo: O controle de deposição de ligninas em diferentes espécies de Eucalyptus foi estudado utilizando baixa temperatura como modulador. Em baixas temperaturas, foi observada redução significativa dos crescimentos foliares de E. camaldulensis, E. grandis e E. pellita e isto pareceu ser um mecanismo adaptativo a este tipo de estresse. Em E. camaldulensis e E. pellita ocorreram reduções significativas dos crescimentos caulinares. Já em E. globulus, foi observado um aumento significativo destes crescimentos, demonstrando existir temperaturas preferenciais para cada espécie que podem estar relacionadas com a distribuição natural das mesmas, bem como com padrões de atividades enzimáticas, expressões gênicas e acúmulo diferencial de ligninas. Foi observada uma atividade diferencial de guaiacol peroxidase (GPX), siringaldazina peroxidase (SPX) e polifenoloxidases (PPO) nas espécies de Eucalyptus expostas às baixas temperaturas. Adicionalmente, foi observado também um padrão de expressão gênica diferenciado para as enzimas envolvidas na biossíntese dos precursores monolignóis das ligninas e variações na deposição de ligninas, indicando haver um efeito dos tratamentos de baixas temperaturas nestes processos. Em E. pellita, as maiores atividades de peroxidases e polifenoloxidases nas regiões apicais das plantas expostas aos tratamentos de baixa temperatura foram acompanhadas de um maior acúmulo de ligninas nessas regiões, bem como de uma redução do crescimento caulinar. Em E. grandis e em E. camaldulensis observou-se que as atividades de peroxidases e polifenoloxidases tendem a ser maiores em baixas temperaturas. Observou-se também uma maior expressão de importantes genes envolvidos na biossíntese dos monolignóis precursores das ligninas, mas isto não foi acompanhado de uma maior deposição de ligninas nestas plantas. Em E. grandis não ocorreram reduções dos crescimentos caulinares em baixas temperaturas, mas em E. camaldulensis as reduções observadas poderiam estar relacionadas como outros fatores, como uma maior degradação de AIA, promovida pelo aumento das atividades de peroxidases. Em E. globulus foram observadas reduções significativas das atividades enzimáticas analisadas, tanto nas amostras de ápices quanto em bases caulinares, expostos às baixas temperaturas. Esta menor atividade enzimática também foi acompanhada de uma menor expressão de genes envolvidos na biossíntese de ligninas. Observou-se uma redução da concentração de ligninas determinadas por ácido tioglicólico nas amostras de ápice e base das plantas expostas às baixas temperaturas e a quantidade de lignina insolúvel e solúvel, determinada pelo método Klason, aumentou nas amostras de ápices. Deste modo, em E. globulus, a maior tendência de redução de ligninas poderia estar associada com o maior crescimento desta espécie em baixas temperaturas. Ao utilizar um estresse como modulador da biossíntese de ligninas, alguns dos genes envolvidos puderam indicar possíveis pontos específicos do metabolismo de ligninas a serem alterados para se produzir plantas melhoradas com menor teor deste polímero / Abstract: The control of lignin deposition in different Eucalyptus species was studied using low temperature as a modulator. Under low temperatures, a significant reduction of leaf growth was observed in E. camaldulensis, E. grandis and E. pellita and this seemed to be an adaptive mechanism to this type of stress. Significant reductions of stem growth were observed for E. camaldulensis and E. pellita. In contrast, a significant increase of stem growth was found for E. globulus, indicating that the optimal growth temperatures for each species might reflect their natural distribution or patterns of enzymatic activities, patterns of gene expression and differential accumulation of lignins. Differential activities of guaiacol peroxidase (GPX), syringaldazine peroxidase (SPX) and polyphenol oxidases (PPO) were observed for the Eucalyptus species exposed to low temperatures. It was also observed that a pattern of differential gene expression exists for the enzymes involved in the biosynthesis of monolignol lignin precursors, as well as variations in lignin deposition, indicating an effect of the low temperature treatments in these processes. The increased peroxidase and polyphenol oxidase activities in the stem apical regions of E. pellita plants exposed to the low temperature treatments were accompanied by an increase in lignin accumulation in these regions. A reduction in stem growth was also found in this species. It was observed that the peroxidase and polyphenol oxidase activities tend to be greater under low temperatures for both E. grandis and E. camaldulensis. Additionally, a transcriptional increase of important genes involved in the biosynthesis of monolignol lignin precursors was found, although this was not accompanied by an increase in lignin deposition in these plants. A reduction in stem growth was not observed at low temperatures for E. grandis but in E. camaldulensis the observed reduction in growth could also be related to others factors, such as a greater degradation of AIA promoted by the increase in the activity of peroxidases. A significant reduction was observed for all of the enzymatic activities analyzed, in both shoot tips and shoot bases of E. globulus plants exposed to low temperature treatments. This lower enzymatic activity was also accompanied by a lower expression of genes involved in lignin biosynthesis. The amount of lignin determined by thioglycollic acid in the samples of shoot tips and shoot bases of the plants exposed to low temperatures was reduced and the amount of acid insoluble and soluble lignin, determined by the method of Klason, increased significantly in the shoot tips. Thus, the tendency of reducing lignin content under cold treatment observed for E. globulus could be associated with its increase in growth at low temperatures. By using a stress as a modulator of lignin biosynthesis, some of the genes involved may indicate possible specific points of lignin metabolism that could be changed when breeding plants for lower content of this polymer / Mestrado / Mestre em Biologia Vegetal

D.Ing. (Civil Engineering) / Please refer to full text to view abstract

Abstract The semi-domesticated reindeer is a northern species of Cervidae that is exposed to extreme seasonal changes in temperature and nutrition in its living environment. The objective of this study was to examine the significance of thermogenic brown adipose tissue (BAT) for the survival of newborn reindeer in the cold during the critical perinatal period. The other main objective was to study the effect of wintertime undernutrition on serum and bone marrow fatty acid composition in yearling reindeer, with particular attention on the proportions of unsaturated and polyunsaturated fatty acids (PUFAs) and their feasibility as indicators of nutritional status. The results showed that the most of the adipose tissues in newborn reindeer were functionally active BAT. The tissue had specific anatomical locations, specialized cell morphological structure, high aerobic capacity, and tissue-specific mitochondrial 32000 Mr-uncoupling protein (UCP1) that is considered a rate-limiting factor for thermogenesis. The most readily mobilized fatty acids from BAT triacylglycerols were arachidonic, linoleic, and α-linolenic acids. BAT was most active at birth and during the close perinatal period but its aerobic capacity declined during the first month of life while UCP1 disappeared and the tissue gradually adopted the histological characteristics of white adipose tissue. The newborn reindeer had very low proportions of the principal C18-PUFAs, linoleic and α-linolenic acids, in serum lipids. However, the proportions of C18-PUFAs increased during the first few days of life by a rate that suggests a selective retention of these fatty acids from milk lipids. A prolonged restricted feeding of reindeer with lichen during winter and spring induced significant reductions in the proportions of linoleic and α-linolenic acids in serum cholesteryl esters and phospholipids, while proportion of arachidonic acid and serum prostaglandin PGF2α metabolite concentration increased. Plasma leptin and insulin levels decreased in parallel with decreases in feed intake and body weight. In freely ranging reindeer, the proportions of oleic acid and principal C18-PUFAs were significantly reduced in femur bone marrow triacylglycerols as a result of a wintertime undernutrition. In conclusion, active BAT is the dominant adipose tissue type in the newborn reindeer and it is likely to have a major significance on the thermoregulatory heat production and cold resistance of reindeer during the perinatal period. The changes in the specific PUFA proportions of serum and bone marrow lipids refleict the changes in the nutritional status and suggest that these fatty acids are preferentially utilized during prolonged wintertime undernutrition.

This thesis examines the function and presentation of “Nature” in American literature written between 1945 and 1971. It argues that the widespread presence of ecological representations of “Nature” within Cold War literature has been critically overlooked, as a result of Cold War literary criticism’s comparatively narrow concentration on the direct effects of political and ideological metanarratives on texts. It uncovers a plethora of ecological portrayals of the relationship between the human and the environment, and reveals the significance of the role played by non-Western and non-Anglocentric philosophies and spiritualties in shaping these presentations. This study is methodologically informed by the most recent developments in the field of ecocriticism, including Scott Knickerbocker’s work on ecopoetics and Timothy Morton’s explorations of the problems associated with the term “Nature”. It finds significant continuities within these ecological portrayals, which suggest that nuclear discourse had an influential effect on the presentation of “Nature” within Cold War literature. This influence is, however, heavily mediated by the role that non-Western and non-Anglocentric philosophies play in writers’ theorisations of relations of interdependence between the human and the environment. Such literary presentations challenge the understanding that the Nuclear Age represents a conquest of “Nature”. Rather, they reveal that a number of Cold War writers present human interdependence within an ecological system, capable of the annihilation of the human, and of the containment of the new nuclear threat. The thesis’s introductory chapter questions the characterisation of Silent Spring (1962) as the founding text of the modern environmental movement. It outlines this study’s intervention into the field of Cold War criticism, detailing its specific ecocritical methodology and engaging with the legacy of Transcendentalism. Chapter One looks at the work of Paul Bowles, with a primary focus on The Sheltering Sky (1949). It demonstrates the centrality of the landscape to the writer’s creative project, and reveals the substantial influence of the Sufi mysticism on Bowles’s presentation of the human’s relationship to the environment. Chapter Two focuses on the work of the New Mexican poet Peggy Pond Church. It establishes the influence of the writer’s familiarity with the Pueblo Native American worldview on her poetic portrayals of the human and the nuclear as interrelated parts within a greater ecological system. It also uncovers similar portrayals within the work of the “father of the atomic bomb”, J. Robert Oppenheimer. The third chapter analyses the effects of Chinese and Japanese literature and thought on the work of J. D. Salinger. It outlines the function of “Nature” in the work of the specific translators that Salinger names, arguing that this translated Taoism substantially informed the ecological vision present across his oeuvre. Chapter Four explores the impact of Simone Weil on the work of Mary McCarthy. It reads Birds of America (1971), demonstrating the governing influence of Weil’s concept of “force” on McCarthy’s presentation of the human as an interdependent part within a powerful ecological system.