Lack of photoreceptor signaling alters the expression of specific synaptic proteins in the retina

Synaptic modulation by activity-dependent changes constitutes a cellular mechanism for neuronal plasticity. However, it is not clear how the complete lack of neuronal signaling specifically affects elements involved in the communication between neurons. In the retina, it is now well established that both chemical and electrical synapses are essential to mediate the transmission of visual signaling triggered by the photoreceptors. In this study, we compared the expression of synaptic proteins in the retinas of wild-type (WT) vs. rd/rd mice, an animal model that displays inherited and specific ablation of photoreceptors caused by a mutation in the gene encoding the beta-subunit of rod cGMP-phosphodiesterase (Pde6b(rd1)). We specifically examined the expression of connexins (Cx), the proteins that form the gap junction channels of electrical synapses, in addition to synaptophysin and synapsin 1, which are involved in the release of neurotransmitters at chemical synapses. Our results revealed that Cx36 gene expression levels are lower in the retinas of rd/rd when compared with WT. Confocal analysis indicated that Cx36 immunolabeling almost disappeared in the outer plexiform layer without significant changes in protein distribution within the inner plexiform layer of rd/rd retinas. Likewise, synaptophysin expression remarkably decreased in the outer plexiform layer of rd/rd retinas, and this down-regulation was also associated with diminished transcript levels. Furthermore, we observed down-regulation of Cx57 gene expression in rd/rd retinas when compared with WT and also changes in protein distribution. Interestingly, Cx45 and synapsin I expression in rd/rd retinas showed no noticeable changes when compared with WT. Taken together, our results revealed that the loss of photoreceptors leads to decreased expression of some synaptic proteins. More importantly, this study provides evidence that neuronal activity regulates, but is not essential to maintain, the expression of synaptic elements. (c) 2008 IBRO. Published by Elsevier Ltd. All rights reserved.

Inhibition of interferon-gamma-induced nitric oxide production in endotoxin-activated macrophages by cytolethal distending toxin

Introduction: Cytolethal distending toxin (CDT) is a DNA-targeting agent produced by certain pathogenic gram-negative bacteria such as the periodontopathogenic organism Aggregatibacter actinomycetemcomitans. CDT targets lymphocytes and other cells causing cell cycle arrest and apoptosis, impairing the host immune response and contributing to the persistence of infections caused by this microorganism. In this study we explored the effects of CDT on the innate immune response, by investigating how it affects production of nitric oxide (NO) by macrophages. Methods: Murine peritoneal macrophages were stimulated with Escherichia coli sonicates and NO production was measured in the presence or not of active CDT. Results: We observed that CDT promptly and significantly inhibited NO production by inducible nitric oxide synthase (iNOS) in a dose-dependent manner. This inhibition is directed towards interferon-gamma-dependent pathways and is not mediated by either interleukin-4 or interleukin-10. Conclusion: This mechanism may constitute an important aspect of the immunosuppression mediated by CDT and may have potential clinical implications in A. actinomycetemcomitans infections.

On the variations of the Betti numbers of regular levels of Morse flows

We generalize results in Cruz and de Rezende (1999) [7] by completely describing how the Beth numbers of the boundary of an orientable manifold vary after attaching a handle, when the homology coefficients are in Z, Q, R or Z/pZ with p prime. First we apply this result to the Conley index theory of Lyapunov graphs. Next we consider the Ogasa invariant associated with handle decompositions of manifolds. We make use of the above results in order to obtain upper bounds for the Ogasa invariant of product manifolds. (C) 2011 Elsevier B.V. All rights reserved.

Ab Initio Calculations of Structural Evolution and Conductance of Benzene-1,4-dithiol on Gold Leads

By performing at) initio density functional theory (DFT) calculations and electronic transport simulations based on the OFT nonequilibrium Green`s functions method we investigate how the conformational changes of a benzene-1,4-dithiol molecule bonded to gold affect the molecular transport as the electrodes are separated from each other. In particular we consider the full evolution of the stretching process until the Junction breaking point and compare results obtained with a standard semilocal exchange and correlation functional to those computed with a self-interaction corrected method. We conclude that the inclusion of self-interaction corrections is fundamental for describing both the molecule conductance and its stability against conformational fluctuations.

Resilience of protein-protein interaction networks as determined by their large-scale topological features

The relationship between the structure and function of biological networks constitutes a fundamental issue in systems biology. Particularly, the structure of protein-protein interaction networks is related to important biological functions. In this work, we investigated how such a resilience is determined by the large scale features of the respective networks. Four species are taken into account, namely yeast Saccharomyces cerevisiae, worm Caenorhabditis elegans, fly Drosophila melanogaster and Homo sapiens. We adopted two entropy-related measurements (degree entropy and dynamic entropy) in order to quantify the overall degree of robustness of these networks. We verified that while they exhibit similar structural variations under random node removal, they differ significantly when subjected to intentional attacks (hub removal). As a matter of fact, more complex species tended to exhibit more robust networks. More specifically, we quantified how six important measurements of the networks topology (namely clustering coefficient, average degree of neighbors, average shortest path length, diameter, assortativity coefficient, and slope of the power law degree distribution) correlated with the two entropy measurements. Our results revealed that the fraction of hubs and the average neighbor degree contribute significantly for the resilience of networks. In addition, the topological analysis of the removed hubs indicated that the presence of alternative paths between the proteins connected to hubs tend to reinforce resilience. The performed analysis helps to understand how resilience is underlain in networks and can be applied to the development of protein network models.

The classification and the conjugacy classes of the finite subgroups of the sphere braid groups

Let n >= 3. We classify the finite groups which are realised as subgroups of the sphere braid group B(n)(S(2)). Such groups must be of cohomological period 2 or 4. Depending on the value of n, we show that the following are the maximal finite subgroups of B(n)(S(2)): Z(2(n-1)); the dicyclic groups of order 4n and 4(n - 2); the binary tetrahedral group T*; the binary octahedral group O*; and the binary icosahedral group I(*). We give geometric as well as some explicit algebraic constructions of these groups in B(n)(S(2)) and determine the number of conjugacy classes of such finite subgroups. We also reprove Murasugi`s classification of the torsion elements of B(n)(S(2)) and explain how the finite subgroups of B(n)(S(2)) are related to this classification, as well as to the lower central and derived series of B(n)(S(2)).

Part-time employment within the Swedish retail business : – A study of part-time employment from a management perspective

Research question: How has the presence of PT employees affected the role of managers in the Swedish food retail business? Research purpose: The purpose of this paper was to describe the change that accompanies part-time employment from a management perspective, and particularly, describe how the presence of part-time employment has influenced the role of the manager within the Swedish food retail business. Conceptual framework: The main focused in this chapter is directed towards the role of managers. The basis of the conceptual framework consist of the model developed by Mintzberg including the ten managerial roles and Quinn's eight leadership roles and how the presence of PT employments might affect these roles. Methodology: In this paper, the authors adopted a qualitative design and used narrative inquiry as a research strategy in order to gain a deep understanding of the context. Semi- structured interviews have been collected through a self-selection sampling and the total number of participants was ten. Conclusions: Based on the findings of this paper the presence of PT employees have not influenced and changed the role of managers. The changes that have influenced and caused the change of the role of the managers constitutes of the increased workload, the delegations of tasks and responsibilities, changed positions, the change of the organisational structure of the individual store, and the increased workforce.

Negotiating collective and individual agency : a qualitative study of young women's reproductive health in rural India

The societal changes in India and the available variety of reproductive health services call for evidence to inform health systems how to satisfy young women's reproductive health needs. Inspired by Foucault's power idiom and Bandura's agency framework, we explore young women's opportunities to practice reproductive agency in the context of collective social expectations. We carried out in-depth interviews with 19 young women in rural Rajasthan. Our findings highlight how changes in notions of agency across generations enable young women's reproductive intentions and desires, and call for effective means of reproductive control. However, the taboo around sex without the intention to reproduce made contraceptive use unfeasible. Instead, abortions were the preferred method for reproductive control. In conclusion, safe abortion is key, along with the need to address the taboo around sex to enable use of "modern" contraception. This approach could prevent unintended pregnancies and expand young women's agency.

Myth and Society: Functions, Uses, and Abuses of Myth in Society

In this work, I will discuss the integral role that myth has in society and then, after presenting several examples of this thesis, I will examine how the integral nature of myth lends itself to certain societal abuses. These abuses often result in unjust social constructs that eventually become attributed to the myth. I would like to proceed in defense of myth; that is, that these constructs are not to be attributed to the myths themselves, rather, society has taken myth and applied it to suit its purposes, ignoring the context in which the myths originated. Hopefully this will raise society's current attitudes toward myth to a level of respect, and will also help to clear myth of its reputation as the origin of injustice and domination.

The value of local partners in Brazil: the effects of ownership clusters and business group membership on firm value in emerging markets

Este estudo analisa como a classe de acionistas afeta o valor das empresas brasileiras listadas na bolsa de valores no ponto de vista da governança corporativa. O trabalho examina a interação entre o valor das empresas e cinco tipos de concentrações acionárias comumente presente em mercados emergentes: famílias, agentes públicos, investidores estrangeiros, executivos e investidores financeiros nacionais. A análise empírica demonstra que o mix e a concentração de participação acionária afeta significativamente o valor das empresas. Utilizando uma compilação única de dados em painel de 2004 a 2008, a presente pesquisa também desenvolve hipóteses sobre o efeito da participação em grupos econômicos para o valor das empresas. A investigação encontra evidências de que, apesar de sua importância para o desenvolvimento de empresas brasileiras, o capital familiar, instituições públicas, e investidores estrangeiros estão cedendo lugar a monitores mais especializados e menos concentrados, como executivos e instituições financeiras nacionais. Estes resultados indicam que a governança corporativa no Brasil pode estar alcançando níveis de maturidade mais elevados. Adicionalmente, apesar de não haver indicação da existência de correlação entre a participação em grupos econômicos e o valor das empresas, os resultados indicam que a presença de um tipo específico de acionista em uma empresa do grupo facilita investimentos futuros desta classe de acionista em outras empresas do mesmo grupo, sinalizando que os interesses acionários são provavelmente perpetuados dentro de uma mesma rede de empresas. Finalmente, a pesquisa demonstra que enquanto o capital familiar prefere investir em empresas com ativa mobilidade do capital, investidores internacionais e instituições públicas procuram investimentos em equity com menor mobilidade de capital, o que lhes garante mais transparência com relação ao uso dos recursos e fundos das empresas.

O planejamento estratégico do capital humano como fator de desenvolvimento sustentável das organizações na agroenergia: estudo de caso

O objetivo desta tese é analisar, orientar e indicar algumas formas de mensuração de resultados das ações ou programas na área de Gestão de Pessoas ao longo dos anos, bem como de novas tendências no setor de agroenergia. O trabalho procura também propor práticas de planejamento estratégico e, indicadores para as organizações com foco no desenvolvimento e nas mudanças previstas nas organizações, no mercado de trabalho, nos modelos de gestão e de negócios do segmento de produção de cana-de-açúcar para os próximos anos. No estudo são analisados as transformações organizacionais, novos desafios competitivos do presente e do futuro, e a forma como a área de Recursos Humanos nas diversas organizações do setor, tem acompanhado tal processo, verificando o impacto dessas ações em um contexto de mudanças nos processos da cadeia agrícola (mecanização do plantio, colheita,.dentre outros), da cadeia industrial (biorefinarias, etanol de segunda geração, gaseificação...dentre outros), e no desenvolvimento organizacional e humano como parte integrante de um programa de sustentabilidade das organizações. São abordados metodologias, sistemas e ferramentas de planejamento estratégico, e mensuração propostas por certos autores que visam a demonstrar o impacto das estratégias e as ações na Gestão de Pessoas em direção ao cumprimento das metas e objetivos das organizações, em um cenário de forte crescimento interno e global do mercado de bioenergia. Nesse cenário, expõe-se e discute-se como as empresas do setor sucroalcooleiro utilizam, na prática, essas metodologias e os indicadores de performance da área frente às necessidades, e indicam-se as melhores práticas e ferramentas que visam a facilitar os processos decisórios, o uso de métricas de Recursos Humanos para previsão e acompanhamento do Capital Humano, e a otimização dos recursos e dos investimentos frente aos novos desafios do setor. Embora já se notem várias iniciativas visando a tornar a Gestão de Pessoas um fator estratégico para as organizações da agroenergia, a pesquisa identificou que a área de Recursos Humanos está evoluindo nessa direção e pode contribuir de forma efetiva para a melhor performance e sustentabilidade dos negócios. Palavras chaves: Cana-de Açúcar, Estratégia Organizacional, Capital Humano

The forward and the equity premium puzzles: two symptoms of the same illness?

The Forward Premium Puzzle (FPP) is how the empirical observation of a negative relation between future changes in the spot rates and the forward premium is known. Modeling this forward bias as a risk premium and under weak assumptions on the behavior of the pricing kernel, we characterize the potential bias that is present in the regressions where the FPP is observed and we identify the necessary and sufficient conditions that the pricing kernel has to satisfy to account for the predictability of exchange rate movements. Next, we estimate the pricing kernel applying two methods: i) one, du.e to Araújo et aI. (2005), that exploits the fact that the pricing kernel is a serial correlation common feature of asset prices, and ii) a traditional principal component analysis used as a procedure 1;0 generate a statistical factor modeI. Then, using on the sample and out of the sample exercises, we are able to show that the same kernel that explains the Equity Premi um Puzzle (EPP) accounts for the FPP in all our data sets. This suggests that the quest for an economic mo deI that generates a pricing kernel which solves the EPP may double its prize by simultaneously accounting for the FPP.

JML- Based formal development of a Java card application for managing medical appointments

Although formal methods can dramatically increase the quality of software systems, they have not widely been adopted in software industry. Many software companies have the perception that formal methods are not cost-effective cause they are plenty of mathematical symbols that are difficult for non-experts to assimilate. The Java Modelling Language (short for JML) Section 3.3 is an academic initiative towards the development of a common formal specification language for Java programs, and the implementation of tools to check program correctness. This master thesis work shows how JML based formal methods can be used to formally develop a privacy sensitive Java application. This is a smart card application for managing medical appointments. The application is named HealthCard. We follow the software development strategy introduced by João Pestana, presented in Section 3.4. Our work influenced the development of this strategy by providing hands-on insight on challenges related to development of a privacy sensitive application in Java. Pestana’s strategy is based on a three-step evolution strategy of software specifications, from informal ones, through semiformal ones, to JML formal specifications. We further prove that this strategy can be automated by implementing a tool that generates JML formal specifications from a welldefined subset of informal software specifications. Hence, our work proves that JML-based formal methods techniques are cost-effective, and that they can be made popular in software industry. Although formal methods are not popular in many software development companies, we endeavour to integrate formal methods to general software practices. We hope our work can contribute to a better acceptance of mathematical based formalisms and tools used by software engineers. The structure of this document is as follows. In Section 2, we describe the preliminaries of this thesis work. We make an introduction to the application for managing medical applications we have implemented. We also describe the technologies used in the development of the application. This section further illustrates the Java Card Remote Method Invocation communication model used in the medical application for the client and server applications. Section 3 introduces software correctness, including the design by contract and the concept of contract in JML. Section 4 presents the design structure of the application. Section 5 shows the implementation of the HealthCard. Section 6 describes how the HealthCard is verified and validated using JML formal methods tools. Section 7 includes some metrics of the HealthCard implementation and specification. Section 8 presents a short example of how a client-side of a smart card application can be implemented while respecting formal specifications. Section 9 describes a prototype tools to generate JML formal specifications from informal specifications automatically. Section 10 describes some challenges and main ideas came acrorss during the development of the HealthCard. The full formal specification and implementation of the HealthCard smart card application presented in this document can be reached at https://sourceforge.net/projects/healthcard/.

Educação profissional: a expansão recente do IFRN e a absorção local dos egressos no mercado de trabalho

This study aims to analyze how IFRN s process of interiorization contributes to endogenization of local and territorial development, more precisely in terms of graduates absorption into the labor market, form of inclusion and increase of income and welfare. The research premise is that the policy of interiorization and expansion of professional and technology education, by decentralizing opportunities, create a differential for the educational and professional trajectory of part of the graduates. This training, however, retain a relative connection with the productive potentialities in the coverage territories. This study includes a review of the literature on education and labor market and a discussion about the role of technical and professional formation for the local development versus the logic of the free market, considering the expansion of public spending for this purpose. For this study two sets of information and data have been collected primarily, with qualitative and quantitative nature. The research with qualitative focus, entitled Pesquisa de Avaliação da Expansão (PAEX), is constituted by series of open interviews applied to institutional representatives, with the purpose of knowing aspects of the interiorization repercussion in the local development process. The research designed to quantity analysis, entitled of the Pesquisa de Acompanhamento de Egressos (PAE), have been put in practice by applying online questionnaire with closed questions to IFRN s former students, aiming to know the form of insertion of the graduates in the labor market and the formation capacity of increasing the welfare, among other things. Empirical data and information fully confirmed the hypothesis of this study, for they really demonstrated that the expansion policy decentralizes opportunities and constitutes an important differential for the professional trajectory of a significant portion of the graduates. However, the graduates employability in the labor market in their territories of coverage is below expectations, due to structural problems of the local economy related to scarcity of jobs, difficulty in wage growth and in professional development. Complementarily, it has been observed institutional difficulties related to the recent implantation process of the policy of professional and technical education in the various campuses of the Institution

Phylogeography and Pleistocene demographic history of the endangered marsh deer (Blastocerus dichotomus) from the Rio de la Plata Basin

The marsh deer is the largest neotropical cervid with morphological and ecological adaptations to wetlands and riparian habitats. Historically, this now endangered species occupied habitats along the major river basins in South America, ranging from southern Amazonia into northern Argentina to the Parana river delta. This particularly close association with wetlands makes marsh deer an excellent species for studying the effects of Pleistocene climatic changes on their demographic and phylogeographic patterns. We examined mitochondrial DNA variation in 127 marsh deer from 4 areas distributed throughout the Rio de]a Plata basin. We found 17 haplotypes in marsh deer from Brazil, Bolivia and Argentina that differed by 1-8 substitutions in a 601 bp fragment of mitochondrial control region sequence, and 486 bp of cytochrome b revealed only 3 variable sites that defined 4 haplotypes. Phylogeny and distribution of control region haplotypes suggest that populations close to the Pantanal area in central Brazil underwent a rapid population expansion and that this occurred approximately 28,000-25,000 years BP. Paleoclimatic data from this period suggests that there was a dramatic increase for precipitation in the medium latitudes in South America and these conditions may have fostered marsh deer's population growth.