When high strength aluminum alloys are subjected to liquid metals, physical and chemical reactions ensue resulting in what is known as liquid metal embrittlement (LME). A subset of environmentally-assisted cracking, LME is exhibited when a liquid metal, e.g. Hg or Ga, comes into intimate contact with a solid metal having significant susceptibility. As mechanical loads are applied, the interaction between the two metals results in a reduction in the flow properties of the solid metal. Several theories have been proposed to identify the underlying microstructural failure mechanism; however, none have been widely accepted, as failures can typically incorporate features common to several failure theories. In an effort to confirm, extend or replace the physically-based theories, fracture mechanics experiments on Al 7075-T651 in liquid mercury have been conducted. Experiments were conducted in a custom environmental chamber capable of exposing specimens to liquid environments while applying a mechanical load. Through both plane-strain fracture and stress intensity factor-dependent (SIF) tests, fracture toughness values along with incubation periods were analyzed and provided data for a load-based theory of LME. These mechanical test data, along with metallographic analysis, show that the phenomena of LME is both strongly time- and SIF-dependent.

Volcanism is the cause of great non-anthropogenic perturbations on the Earth climate through energy imbalance changes. There is still much to be uncovered relative to its impacts on the Southern Hemisphere, even more with respect to the Southern Ocean. The South Atlantic and its Southern Ocean sector response to volcanism are examined using simulation results from the Last Millennium Ensemble Experiment of the Community Earth System Model (CESM-LME), for the period 850-2005. Composite results point to significant changes in sea surface temperature and salinity in the first austral summer following the eruption. North of 60S, there is ocean cooling, as expected because of the higher albedo related to the volcanic forcing. In contrast, near the Antarctic Peninsula in the Weddell Sea, a local warming of ∼ 0.8ºC is observed (significant at the 90% level). Salinity shows positive anomaly (∼0.1) at the northern region off Antarctic Peninsula from the first year after the eruption to the fourth subsequent year. Oceanic surface anomalies weaken after the fifth subsequent year, however it is still present in deeper layers (∼500m). At the same time, wind stress changes are evident, results show a poleward shift (∼2º), strengthening (∼10%) of the prevailing westerlies and the reversal in direction of the meridional wind stress component in the northern Antarctic Peninsula. As consequence, there is intensification of the Antarctic Circumpolar Current southern extension. Together with the stronger westerlies, the mixing in the northern Antarctic Peninsula is enhanced, bringing up warmer subsurface waters, therefore explaining the anomalous surface warming after the eruption. The 1991 Mt. Pinatubo eruption response is also investigated. CESM-LME, observations and reanalysis have shown similar behavior, however for the second subsequent year, thus suggesting the occurrence of the same mechanism identified after Last Millennium eruptions. / Vulcanismo é uma das maiores causas naturais de mudanças no clima. Poucos estudos tiveram foco no seu impacto no hemisfério sul, principalmente no Oceano Austral. Desta forma, o impacto de erupções vulcânicas é investigado no Oceano Atlântico Sul incluindo o seu setor austral, em resultados do modelo CESM-LME (Community Earth System Model Last Millennium Ensemble) entre 850 e 2005. Os resultados utilizando composições mostram mudanças significativas na temperatura e salinidade da superfície do oceano no primeiro verão austral depois da erupção. Ao norte de 60S, há uma anomalia negativa de ∼ -0.8ºC na temperatura em superfície, devido ao maior albedo após a erupção. No entanto, próximo à Península Antártica no Mar de Weddell, é visto uma anomalia positiva de ∼0.8ºC (significativa a 90%). A salinidade apresenta mudanças importantes entre o primeiro e o quarto ano após a erupção, com anomalia positiva (∼0.1) ao norte da Península Antártica. A resposta ao vulcanismo em superfície desaparece no quinto ano sequente, mas permanecem anomalias em profundidade (∼500m). O campo de vento também se altera no mesmo ano, os ventos de oeste migram para sul (∼2º) e se intensificam (∼10%), além da componente meridional inverter seu sentido ao norte da Península Antártica. Como consequência, é observada intensificação da borda sul da Corrente Circumpolar Antártica. Junto com isto, há aumento da mistura próximo à Península Antártica, desta forma, águas subsuperficiais mais quentes afloram, explicando a anomalia quente após a erupção. Finalmente, é verificada a ocorrência de resposta similar após a erupção do Monte Pinatubo (1991). Resultados do CESM-LME tiveram comportamento aproximado quando comparados com dados observacionais e reanálise. O aquecimento próximo à Península Antártica é evidenciado no segundo ano após a erupção, sugerindo a ocorrência do mesmo mecanismo do último milênio.

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近年來，國際經濟發展相當快速，倫敦金屬交易所(LME)的銅價由2008年12月平均每噸3,071美元，上漲至2013年11月每噸7,066.4美元，成長了超過一倍以上，銅在工業上被廣泛應用，是不可或缺的重要原料，在西元1877年時，最早出現的銅期貨契約是在倫敦期貨交易所(LME)交易，銅也是LME最早進行交易的商品之一，LME其成交量也最大，成為國際貿易上交易熱絡的商品之一。 由於銅的生產集中於少數廠商，任何影響到主要產國或銅礦公司正常運作的消息，都可能使得銅價變動，而美國即是生產銅的重要國家之一。美國自2008年因次貸風暴引發金融危機，聯準會(Fed)便開始採取各種措施穩定金融秩序與提供市場流動性，其中最受關注的做法就是量化寬鬆(Quantity Easing; QE)的貨幣政策，而這項政策是否與銅價的變化具有關聯性，即是本研究的目的，而研究結果如下： 一、上海期貨交易所(SHFE)與倫敦金屬交易所(LME)公告之銅價皆會受前一期 數值影響； 二、趨勢調整後上海期貨交易所(SHFE)公告之銅價的指數平滑模型之預測力相 對較好； 三、在美國量化寬鬆貨幣政策第一輪及第二輪實施期間，釋出資金規模對銅價呈 正向關係； 四、在美國量化寬鬆貨幣政策第三輪實施期間，釋出資金規模對銅價呈負向影響 關係；

近年來各國推行寬鬆貨幣政策，導致各項金融商品價格波動劇烈，企業經營風險大幅提高，企業惟有建立有效的風險管理機制，進行相關的營運避險與財務避險策略，減少或規避風險，才能確保穩定的獲利來源，達到永續經營目的。 本論文以電線電纜業的避險作業為研究對象，除了簡單論述企業風險管理理論與避險理論外，同時介紹實務上電線電纜業常見的避險方式，並配合原料採購計價模式，結合銷貨、採購、製造等流程，提出多項避險作業流程建議，以有效控制原料成本，達成獲利目標。 對於曝險部位執行避險或不避險的選擇性避險行為（Selective Hedging），是多數企業時常面對的問題。「一單一鎖」完全避險的傳統避險理論是否就是企業最佳的避險策略，或是如何在一家企業的風險胃納（Risk Appetite）之下建立最適避險比例（Optimal Hedge Ratio），盼能藉此論文，以廠商的實務避險需求引領未來更多的學術研究。

Spline smoothers as implemented in common mixed model software provide a familiar framework for estimating semi-parametric and non-parametric models. Following a review of literature on splines and mixed models, details for implementing mixed model splines are presented. The examples use an experiment in the health sciences to demonstrate how to use mixed models to generate the smoothers. The first example takes a simple one-group case, while the second example fits an expanded model using three groups simultaneously. The second example also demonstrates how to fit confidence bands to the three-group model. The examples use mixed model software as implemented in lme() in R. Following the examples a discussion of the method is presented.

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A des dates et à des vitesses différentes selon les pays, l’aluminium a changé tout à la fois le monde industriel et les modes de vie. Au début du XXème siècle, le monde en développement était déjà partagé entre l’Amérique du Nord où acier et béton commençaient à façonner les villes reliées par le chemin de fer, et l’Europe où il fallait détruire pour reconstruire et où le changement a pris plus de temps. Aluminium et hydroélectricité ont effectué leurs débuts ensemble, ouvrant une longue période de croissance que leur complémentarité a accélérée. Les réussites techniques dans les deux domaines ont eu un effet boule de neige. L’expansion a duré ¾ de siècle jusqu’à ce que l’augmentation des usages domestiques de l’électricité contraigne la production d’aluminium à trouver de nouvelles sources de courant, au sein des États-Unis d’abord. Les pays en développement ont adopté le chemin suivi auparavant et assuré la continuité. Depuis 2003, la Chine est le premier producteur mondial d’aluminium. La modernisation a touché tous les domaines en même temps, sant apparaître des besoins considérables d’accompagnement. L’économie et la gestion ont construit et développé des bases théoriques et pratiques en réseau, amplifiant l’efficacité des progrès techniques. Ce qu’il a paru intéressant de mettre en lumière dans cette étude, ce sont les interactions durables entre la théorie économique et la production industrielle d’un métal qui a façonné le siècle. / At different times and speeds, depending on the countries concerned, aluminium has transformed both the world of industry and our ways of life. In the early 20th century, the developing world was already divided between North America, where steel and concrete were beginning to shape cities linked by railroads, and Europe, where it was necessary to demolish before rebuilding, and the transformation therefore took longer. Aluminium and hydroelectricity emerged together, heralding a long period of growth that was accelerated by their complementarity. Technical progress in both domains had a snowball effect. The expansion lasted three-quarters of a century, until the rising household demand for electricity forced aluminium producers to look for new sources of energy, firstly in the United States. The developing countries followed the same path and provided continuity. China has been the leading aluminium producer in the world since 2003. Modernisation affected both domains at the same time, creating considerable needs for support. Economics and management sciences have developed theoretical and practical foundations in a network, amplifying the effectiveness of technical advances. The interest of this study lies in our revelation of the lasting interactions between economic theory and industrial production.

Submitted by Nathalya Silva (nathyjf033@gmail.com) on 2017-05-30T15:28:20Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_EfeitosTransplanteAutologo.pdf: 9589960 bytes, checksum: 3fa8fabed3fd1b35a66ff2eb5b3ffccf (MD5) / Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2017-06-06T19:40:02Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_EfeitosTransplanteAutologo.pdf: 9589960 bytes, checksum: 3fa8fabed3fd1b35a66ff2eb5b3ffccf (MD5) / Made available in DSpace on 2017-06-06T19:40:02Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_EfeitosTransplanteAutologo.pdf: 9589960 bytes, checksum: 3fa8fabed3fd1b35a66ff2eb5b3ffccf (MD5) Previous issue date: 2017-03-30 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / A lesão da medula espinhal (LME) causa perda permanente da função neurológica abaixo do nível de lesão, gerando consequências físicas sociais e psicológicas nos pacientes. A fisiopatologia da LME envolve processos complexos, como hemorragia, excitotoxicidade e inflamação, geradas principalmente pelas células microgliais. Apesar do avançado conhecimento sobre os mecanismos patológicos, ainda não existem estratégias terapêuticas eficazes e aprovadas para o tratamento das lesões e suas consequências sem que tenham efeitos adversos graves. A terapia celular pode representar uma boa estratégia terapêutica por demonstrar bons resultados na modulação do ambiente inflamatório da lesão e por prováveis mecanismos de diferenciação. No presente estudo, investigamos a ação das células mononucleares da medula óssea (CMMO) em lesões incompletas (hemissecção à direita da medula espinhal, segmento T8-T9) após 42 dias de lesão (lesão crônica). As células eram do próprio animal lesionado (transplante autólogo) e o transplante foi intramedular, ou seja, as células eram inseridas próximas ao local da lesão. No presente estudo, investigaram-se os efeitos funcionais do transplante por meio da escala BBB (Basso, Beatie e Bresnahan), que permite graduar a função motora das patas posteriores dos animais. Investigou-se também os efeitos antiinflamatórios das CMMO. Foram utilizadas técnicas histológicas e imunohistoquímicas usando a coloração de Violeta de Cresila e os anticorpos anti-ED-1 (marcador de micróglia/macrófagos ativados) e anti-GFAP (marcador de astrócitos fibrilares). Foram realizadas análises qualitativas e quantitativas. Para análise quantitativa, o número de astrócitos e macrófagos/micróglia ativados por campo foram contados usando microscópio binocular com gradícula de contagem (0,0625mm2) em objetiva de 40x. As médias das contagens e os desvios-padrão obtidos foram plotados em coordenadas cartesianas. A contagem se deu da seguinte forma: no lado direito da medula espinhal (lado com lesão) e três campos por região medular (funículo ventral - FV, funículo dorsal - FD, funículo lateral - FL, corno dorsal - CD, corno ventral - CV e substância cinzenta intermediária-SCI), totalizando 18 campos de contagem por secção. O tratamento com CMMO não foi eficaz para melhorar a função motora dos animais lesionados quando comparamos os animais tratados e não tratados (médias e desvios-padrão dos grupos: falso operado, n=4, 21±0; controle, n=4, 13,57±3,88; tratado, n=5, 15,07±3,46). Na análise qualitativa por meio da coloração de Violeta de Cresila, os animais tratados apresentaram melhor preservação tecidual quando comparados com os animais não tratados. Na análise quantitativa da ativação microglial, observamos que o tratamento com as CMMO reduziu a ativação dessas células inflamatórias (controle: 19,52±7,79; tratados: 10,04±2,37), porém não reduziu significativamente a ativação dos astrócitos (médias dos grupos: controle 17,74± 2,757; tratados 14,46± 5,283). Os resultados sugerem que mais estudos são necessários para chegar-se a uma estratégia eficaz para os pacientes com LME. Um possível tratamento combinado com outras estratégias pode vir a ser promissor para a funcionalidade dos pacientes. / Spinal cord injury (SCI) causes permanent loss of neurological function below the level of injury, generating social and psychological physical consequences in patients. The pathophysiology of SCI involves complex processes, such as hemorrhage, excitotoxicity and inflammation, mainly generated by microglial cells. Despite advanced knowledge of pathological mechanisms, effective and approved therapeutic strategies for the treatment of lesions and their consequences are still lacking without serious adverse effects. Cell therapy may represent a good therapeutic strategy because it demonstrates good results in the modulation of the inflammatory environment of the lesion and by probable mechanisms of differentiation. In the present study, we investigated the action of bone marrow mononuclear cells (BMMC) in incomplete lesions (hemisection to the right of the spinal cord, T8-T9 segment) after 42 days of injury (chronic lesion). The cells were from the injured animal itself (autologous transplantation) and the transplantation was intramedullary, i.e. the cells were inserted near the site of the lesion. In the present study, the functional effects of transplantation were investigated through the BBB scale (Basso, Beatie and Bresnahan), which allows the motor function of the hind legs of the animals to be graded. The anti-inflammatory effects of BMMC were also investigated. Histological and immunohistochemical techniques using Cresila Violet staining and anti-ED-1 (microglial marker / activated macrophages) and anti-GFAP (fibrillar astrocyte marker) antibodies were used. Qualitative and quantitative analyzes were performed. For quantitative analysis, the number of field activated astrocytes and macrophages / microglia were counted using binocular microscope with counting gradient (0.0625mm2) in a 40x objective. The counting averages and the standard deviations obtained were plotted in Cartesian coordinates. The counting was as follows: on the right side of the spinal cord (lesion side) and three fields per medullary region (ventral funiculus - FV, dorsal funiculus - FD, lateral funiculus - FL, dorsal horn - CD, ventral horn - CV and intermediate gray matter-SCI), totaling 18 counting fields per section. Treatment with BMMC was not effective in improving the motor function of the injured animals when we compared the treated and untreated animals (means and standard deviations of the groups: false operated, n = 4, 21 ± 0, control, n = 4, 13,57 ± 3.88, treated, n = 5, 15.07 ± 3.46). In the qualitative analysis by means of the staining of Cresila Violet, treated animals presented better tissue preservation when compared to the untreated animals. In the quantitative analysis of microglial activation, we observed that treatment with BMMC reduced the activation of these inflammatory cells (control: 19.52 ± 7.79, treated: 10.04 ± 2.37), but did not significantly reduce the activation of the astrocytes (Mean of the groups: control 17.74 ± 2.757, treated 14.46 ± 5.283). The results suggest that further studies are needed to come up with an effective strategy for patients with SCI. A possible combined treatment with other strategies may turn out to be promising for patients' functionality.

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