Optical Spectroscopy of Wide Bandgap Semiconductor Heterostructures and Group-IV Alloy Quantum Dots

Efficient and robust blue InGaN multiple quantum well (MQW) light emitters have become ubiquitous; however, they still have unattained theoretical potential. It is widely accepted that “localization” of carriers due to indium fluctuations theoretically enhance their efficiency by moderating defect-associated nonradiative recombination. To help develop a complete understanding of localization effects on carrier dynamics, this thesis explores degree of localization in InGaN MQWs and its dependence on well thickness and number of wells, through temperature and power dependent photoluminescence measurements. Additionally, silicon-compatible, nontoxic, colloidally synthesizable 2-5 nm Ge1-xSnx alloy quantum-dots (QDs) are explored for potential visible to near-IR optoelectronic applications. While bulk Ge is an indirect gap material, QD confinement allows enhanced direct transitions, and alloying with Sn improves transition oscillator strengths. Temperature dependent steady-state and time-resolved photoluminescence reveal relaxation pathways involving bright/dark excitons and surface states in Ge1-xSnx QDs, showing their great potential for future use

p53: The Attractive Tumor Suppressor in the Cancer Research Field

p53 is one of the most studied tumor suppressors in the cancer research field. Of note, over 50% of human tumors carry loss of function mutations, and thus p53 has been considered to be a classical Knudson-type tumor suppressor. From the functional point of view, p53 is a nuclear transcription factor to transactivate a variety of its target genes implicated in the induction of cell cycle arrest, DNA repair, and apoptotic cell death. In response to cellular stresses such as DNA damage, p53 is activated and promotes cell cycle arrest followed by the replacement of DNA lesions and/or apoptotic cell death. Therefore, p53 is able to maintain the genomic integrity to prevent the accumulation of genetic alterations, and thus stands at a crossroad between cell survival and cell death. In this paper, we describe a variety of molecular mechanisms behind the regulation of p53

p73-Binding Partners and Their Functional Significance

p73 is one of the tumor-suppressor p53 family of nuclear transcription factor. As expected from the structural similarity between p53 and p73, p73 has a tumor-suppressive function. However, p73 was rarely mutated in human primary tumors. Under normal physiological conditions, p73 is kept at an extremely low level to allow cells normal growth. In response to a certain subset of DNA damages, p73 is induced dramatically and transactivates an overlapping set of p53-target genes implicated in the promotion of cell cycle arrest and/or apoptotic cell death. Cells undergo cell cycle arrest and/or apoptotic cell death depending on the type and strength of DNA damages. p73 is regulated largely through the posttranslational modifications such as phosphorylation and acetylation. These chemical modifications are tightly linked to direct protein-protein interactions. In the present paper, the authors describe the functional significance of the protein-protein interactions in the regulation of proapoptotic p73

Management of Patients with Ischemic Stroke

In a case with embolic occlusion of cerebral artery, residual cerebral blood flow (CBF) in symptomatic ischemic region is distributed heterogeneously and cerebral infarction is developed gradually from ischemic core to penumbra. Ischemic core is defined as a region with irreversible tissue damage due to fairly poor collateral circulation, and ischemic penumbra is defined as a region with preservation of tissue reversibility in a certain time. Reversibility of ischemic penumbra is also depending on both residual CBF and time from stroke onset, and the existence of ischemic penumbra is essential for thrombolytic therapy. Ischemic penumbra is thought to be the first therapeutic target in management of patients with acute cerebral ischemia. Using 133Xe SPECT imaging, penumbral flow is estimated as 15-30 m1/100g/min within 3 hours from stroke onset and 20-30 m1/100g/min during 3-6 hours from stroke onset. Ischemic penumbra could be diagnosed accurately by both negative findings on DWI and critical flow level in brain perfusion SPECT or other perfusion image. Hemodynamic cerebral ischemia could be stratified into Stage I and Stage II (Misery perfusion). According to vasodilatory and metabolic compensation toward reduction of cerebral perfusion pressure, Stage I ischemia is defined as both preservation of resting CBF and reduction of vascular reserve (VR). Stage II ischemia is defined as reduction of resting CBF associated with loss of VR. The vasodilatory response to acetazolamide provides an effective parameter of VR: (acetazolamide-activated CBF / resting CBF ? 1) X 100%. Stage II ischemia is quantitatively defined as both CBF less than 80% of normal mean CBF and VR less than 10%. Stratification of hemodynamic cerebral ischemia could be important to determine future risk of stroke. Stage II ischemia is thought to be the second therapeutic target in management of patients with hemodynamic cerebral ischemia. The characteristics and kinetics of brain perfusion radiotracers should be considered in quantitative stratification of hemodynamic cerebral ischemia using brain perfusion SPECT

RISCOS SOCIOAMBIENTAIS: PENSAMENTOS DE ULRICH BECK

RESUMO Este artigo aborda analiticamente os pensamentos de Ulrich Beck sobre os riscos do planeta Terra. Este pensador alemão, que formulou os fundamentos dos “Riscos Sociais”, na década de 1980, passa a ser mundialmente conhecido somente na década seguinte, quando a sua obra “Risk Society” foi traduzida para o inglês. Após essa publicação, Beck publicou várias obras, cujas temáticas sempre foram voltadas para compreender a sociedade contemporânea. Os conteúdos da sua pesquisa sempre foram embasados nas discussões sobre o ambiente e as atividades humanas, do ponto de vista ecológico e político. Considerado como um filósofo e analista crítico da sociedade pós-industrial, fez alertas sobre as emergências e as incertezas do século XXI, considerando o presente momento como “Cosmopolitan Moment”. Esta característica contemporânea, que gera um impulso cosmopolita, possibilita transformações da sociedade atual, onde os níveis local, nacional e global se revestem de simultaneidade, abrindo espaços sobre mudanças culturais, solidariedade, racionalidade, liberdade, democracia e legitimação. É a nossa própria condição e opção da sociedade de conhecimento. Os Riscos Sociais são complexos e representam riscos para toda a sociedade. Os riscos estão onipresentes, não respeitando fronteiras políticas ou culturais e pela sua incalculabilidade, e des-localização, tanto no espaço como no tempo, torna-se imprevisível. Desta forma, estamos diante de grandes desafios sociais, político-econômicos e financeiros, onde mudanças paradigmáticas culturais e políticas terão que ser assumidas. Palavras-chave: Ulrich Beck. Riscos Sociais. Momento Cosmopolita. Pensamento Ambiental. Planeta Emergente. Riscos Ambientais. ABSTRACT This paper discusses analytical Ulrich Beck’s thoughts about the risks of planet Earth. This German thinker, who formulated the concepts of the "Social Risks" in the 1980s, becomes widely known only in the following decade, when his book "Risk Society" was translated into English. After this publication, Beck published several works, whose themes have always been directed to understanding contemporary society. The contents of his research have always been based on discussions about the environment and human activities, under ecological and political views. Regarded as a philosopher and critical analyst of post-industrial society, he made alerts about emergencies and the uncertainties of XXI century, considering the present moment as "Cosmopolitan Moment". This contemporary feature, which created a cosmopolitan pulse, enables transformations of modern society, where the local, national and global levels are simultaneity, opening spaces on cultural changes, solidarity, rationality, freedom, democracy and legitimacy. It is our own condition and choice of the knowledge society. The Social Risks are complex and pose risks to society. The risks are omnipresent, not respecting political or cultural boundaries and its incalculability, and de-localization, both in space and time, and it becomes unpredictable. Thus, great social, political, economic and financial challenges are faced, where cultural and political paradigm transformations have to be assumed. Keywords: Ulrich Beck. Social risks. Cosmopolitan Moment. Environmental thinking. Planet Emergent. Environmental Risk

Muscle Atrophy and Motor Neuron Degeneration in Human NEDL1 Transgenic Mice

Amyotrophic lateral sclerosis (ALS) is the most frequent adult-onset motor neuron disease. Approximately 20% cases of familial ALS show the mutation in the superoxide dismutase-1 (SOD1) gene. We previously demonstrated that homologue to E6AP carboxyl terminus- (HECT-) type ubiquitin protein E3 ligase (NEDL1) physically bind to mutated SOD1 protein but not wild-type SOD1 and promote the degradation of mutated SOD1 protein through ubiquitin-mediated proteasome pathway. To further understand the role of NEDL1 involved in the pathogenesis of familial ALS, we generated transgenic mice with human NEDL1 cDNA. The transgenic mice with human NEDL1 expression showed motor dysfunctions in rotarod, hanging wire, and footprint pattern examination. Histological studies indicated degeneration of neurons in the lumbar spinal cord and muscle atrophy. The number of activated microglia in the spinal cord of transgenic mice was significantly higher than that of wild-type mice, suggesting that inflammation might be observed in the spinal cord of transgenic mice. In conclusion, these findings suggest that the human NEDL1 transgenic mice might develop ALS-like symptoms, showing signs of motor abnormalities, accompanied with significant reduction in muscle strength

Alocação de pessoas na cisão de empresa do setor elétrico: um estudo de caso

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção.O presente estudo procurou conhecer o trabalho dos gerentes para a alocação de pessoas paras as empresas Alfa e Beta1, durante a administração do processo de cisão da empresa Alfa ocorrida em dezembro de 1997. O estudo envolveu também a identificação das decisões individuais tomadas pelos gerentes na escolha da empresa onde trabalhariam após a cisão. O foco da pesquisa concentrou-se nos gerentes que administravam a atividade meio da empresa, por ser o ponto de maior impacto do processo. A corrente metodológica adotada é a fenomenologia (pesquisa qualitativa), o método empregado é o estudo de caso e para a coleta de dados utilizou-se de amostra intencional e entrevista semi-estruturada. O estudo foi realizado através de fundamentos teóricos compostos pela literatura disponível e por dados levantados entre seis gerentes (na ativa ou aposentado) dessas empresas. Os resultados obtidos apontam similaridade nas práticas adotadas pelos gerentes bem como sustentação em Ramos (1983, 1984, 1989), quando analisados sob o prisma dos modelos de homem, ação administrativa e o sistema cognitivo do corpo funcional e gerencial

NOTAS SOBRE O SIMPÓSIO NACIONAL: GEOGRAFIA, PERCEPÇÃO E COGNIÇÃO DO MEIO AMBIENTE

Foi realizado, nos dias 08, 09 e 10 de junho de 2005, na cidade de Londrina, com promoção do Laboratório de Pesquisas Urbanas e Regionais, do Departamento de Geociências, do Centro de Ciências Exatas da Universidade Estadual de Londrina, o primeiro Simpósio Nacional sobre Geografia, Percepção e Cognição do Meio Ambiente. A estrutura do evento foi composta por de uma Conferência de Abertura, quatro Mesas Redondas e vinte Sessões Temáticas. O Simpósio se constituiu em homenagem à professora Doutora Lívia de Oliveira geógrafa, educadora, pesquisadora e pioneira na introdução e no desenvolvimento de pesquisas voltadas à Percepção e Cognição do Meio Ambiente que, desde a década de 1970, tem influenciado estudantes e pesquisadores da Geografia e de áreas afins. Assim, um dos objetivos do evento foi congregar estudiosos e pesquisadores de várias universidades brasileiras em torno de estudos que se iniciaram com as fronteiras abertas pela Geografia Humanística11, tendo a Fenomenologia, como um de seus caminhos. O conhecimento e a difusão de muitas pesquisas que vinham sendo realizadas pelos pesquisadores foi um ponto alto do simpósio. O intercâmbio que se estabeleceu no evento atingiu o objetivo, de aglutinar e discutir as várias vertentes reveladas nesse encontro, como a questão da linguagem, da literatura, da identidade, da saúde, da cultura, da arte-imagem etc. Recorrendo a novos conceitos, metodologias e áreas de conhecimento distintas da Geografia, a prática interdisciplinar passa a ser incorporada gradativamente ao amplo leque do saber geográfico. Participaram desse evento, 199 inscritos, professores, pesquisadores, alunos de pós-graduação e estudantes interessados na temática, procedentes de treze estados brasileiros: Rio Grande do Sul, Santa Catarina, Paraná, São Paulo, Rio de Janeiro, Mato Grosso do Sul, Minas Gerais, Bahia, Goiás, Distrito Federal, Ceará, Paraíba e Rio Grande do Norte. Além de geógrafos, houve participação de profissionais e alunos de várias áreas de conhecimento, como psicólogos, historiadores, arquitetos, sociólogos, advogados, agrônomos, pedagogos, etc