904 resultados para CCM-DEAD


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Universidade Estadual de Campinas . Faculdade de Educação Física

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O domínio do Cerrado compreende uma área contínua nos estados centrais do Brasil e áreas disjuntas em outros estados, incluindo São Paulo. Essa vegetação ocupava originalmente 21% do território brasileiro, restando atualmente apenas 21,6% de sua extensão original. A área recoberta por essa vegetação em São Paulo cobria 14% de sua área total e seus remanescentes recobrem menos de 1% da ocorrência original dessa vegetação. Estudos recentes indicam que o valor da produtividade líquida no Cerrado Pé-de-Gigante (SP) constitui um pequeno dreno de carbono e indicou que a sazonalidade foi o fator determinante do valor observado. Os estudos dos fluxos de carbono em ecossistemas terrestres são raramente acompanhados de abordagens ecofisiológicas de modo a explorar a relação funcional das espécies que compõem o ecossistema e os valores líquidos obtidos para o mesmo. Assim, o objetivo deste trabalho foi caracterizar estruturalmente a vegetação presente na área de maior influência da torre de fluxo instalada no Cerrado Pé-de-Gigante, visando possibilitar estudos relacionados à quantificação em longo prazo da dinâmica dos fluxos de água, energia e CO2 na vegetação de Cerrado. Para isso foram levantadas 20 parcelas (10 x 10 m) em 0,2 ha de Cerrado, e amostraram-se todas as plantas com perímetro ao nível do solo >6 cm (exceto lianas e árvores mortas). A distribuição das classes de diâmetro e estrutura vertical, assim como os parâmetros fitossociológicos foram analisados. Encontramos 1451 indivíduos, distribuídos em 85 espécies, 52 gêneros e 31 famílias. A densidade absoluta e área basal foram de 7255 ind. ha-1 e de 7,9 m².ha-1, respectivamente. A família Leguminosae apresentou o maior número de espécies (13). O Índice de diversidade de Shannon (H') foi 3,27 nats.ind-1. A distribuição em classes de diâmetro mostrou uma curva de "J" invertido, estando a maioria dos indivíduos na primeira classe. Concluímos que a área deve ser classificada como Cerrado denso, devido principalmente à dominância pela espécie arbórea Anadenanthera falcata, cuja ocorrência no estado foi relatada apenas em locais com solos ricos em saturação de bases na região das Cuestas Basálticas, devido também à maior área basal dos indivíduos, comparando com outros fragmentos de Cerrado. Além da espécie citada, Myrcia lingua e Xylopia aromatica, apresentaram os maiores IVI (Valor de importância).

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Neste artigo visamos apontar, apoiadas em W. Benjamim e G. Agamben, a fragilização do registro da experiência e sua incidência na lógica do poder/violência. Analisamos, pretendendo desmistificar a eficácia dos discursos mortificadores da experiência, a figura do "mulçumano"; - nome que designava os mortos-vivos nos campos de concentração, conforme relato de Primo Levi e outros. Tal figura é emblemática do estado limite a que chegaram algumas pessoas e podem expressar o destino de alguns sujeitos na contemporaneidade. Pudemos identificar nessa posição tanto um movimento na direção da perda do laço identificatório com o semelhante, como uma forma de resistência à violência perpetrada pelo discurso social. Tal resistência consiste em operar uma mimese ao objeto resto, o que permite ao sujeito a manutenção da estrutura fantasmática. Indicamos que, apesar das estratégias do poder, o sujeito reinventa modos de se situar na relação ao Outro, nos quais se fazem importantes a presença e a palavra, incluindo aí a experiência psicanalítica.

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The weevil subfamily Scolytinae includes beetles which may feed on the bark, trunk or roots of both live and dead trees and are sometimes considered forest and silvicultural pests. Less frequently, some species feed on seeds and may be cause economic losses when associated to plant cultivars. Spermophthorus apuleiae Costa-Lima is a Neotropical Scolytinae formerly recorded to be "associated" with seeds of Caesalpinia ferrea var. leiostachya Benth, a Brazilian tree popularly known in Portuguese as "pau-ferro". Hitherto, it was not clear whether these beetles actually feed on the seeds of that plant. In order to investigate the ability of S. apuleiae to feed on seeds of "pau-ferro", observations were done and colonies of these beetles were established. Both in the field and in captivity the beetles were not observed feeding on the seeds. Even when beetles were exposed to seeds as the only source of food they were incapable of boring or eating the seeds and died. Our data therefore suggest that S. apuleiae is a frugivorous species which peculiarly does not eat seeds of "pau-ferro".

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Rabies is a viral zoonotic infectious disease that affects mammals and is caused by genotypes/species of the Lyssavirus genus (Rhabdoviridae, Mononegavirales), with the genotype 1 (classic rabies virus - RABV) being the most prevalent. Despite continuous efforts, rabies is still an incurable disease that causes thousands of deaths amongst humans worldwide. Due to a wide range of hosts and the different evolutionary paths of RABV in each host, several host-specific variants have arisen in an ongoing process. The result of RABV replication in nervous tissues may lead to two opposite clinical outcomes, i.e., paralytic/dumb form and encephalitic/furious one. The paralytic form creates dead-end hosts mainly amongst herbivores, while the furious form of the disease allows for augmented transmission when manifested in gregarious carnivores, as their natural aggressive behavior is accentuated by the disease itself. The aim of this article is to propose a theoretical model intended to explore how the rabies virus intrinsically modulates the immune system of different host classes, the pathological changes that the virus causes in these animals and how these elements favor its own perpetuation in nature, thus providing a basis for better prediction of the patterns this disease may present.

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Background: Toll-like receptor 4 (TLR4) is widely recognized as an essential element in the triggering of innate immunity, binding pathogen-associated molecules such as Lipopolysaccharide (LPS), and in initiating a cascade of pro-inflammatory events. Evidence for TLR4 expression in non-immune cells, including pancreatic beta-cells, has been shown, but, the functional role of TLR4 in the physiology of human pancreatic beta-cells is still to be clearly established. We investigated whether TLR4 is present in beta-cells purified from freshly isolated human islets and confirmed the results using MIN6 mouse insulinoma cells, by analyzing the effects of TLR4 expression on cell viability and insulin homeostasis. Results: CD11b positive macrophages were practically absent from isolated human islets obtained from nondiabetic brain-dead donors, and TLR4 mRNA and cell surface expression were restricted to beta-cells. A significant loss of cell viability was observed in these beta-cells indicating a possible relationship with TLR4 expression. Monitoring gene expression in beta-cells exposed for 48h to the prototypical TLR4 ligand LPS showed a concentration-dependent increase in TLR4 and CD14 transcripts and decreased insulin content and secretion. TLR4-positive MIN6 cells were also LPS-responsive, increasing TLR4 and CD14 mRNA levels and decreasing cell viability and insulin content. Conclusions: Taken together, our data indicate a novel function for TLR4 as a molecule capable of altering homeostasis of pancreatic beta-cells.

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Wild felids and canids are usually the main predators in the food chains where they dwell and are almost invisible to behavior and ecology researchers. Due to their grooming behavior, they tend to swallow shed hair, which shows up in the feces. DNA found in hair shafts can be used in molecular studies that can unravel, for instance, genetic variability, reproductive mode and family structure, and in some species, it is even possible to estimate migration and dispersion rates in given populations. First, however, DNA must be extracted from hair. We extracted successfully and dependably hair shaft DNA from eight wild Brazilian felids, ocelot, margay, oncilla, Geoffroy's cat, pampas cat, jaguarundi, puma, and jaguar, as well as the domestic cat and from three wild Brazilian canids, maned wolf, crab-eating fox, and hoary fox, as well as the domestic dog. Hair samples came mostly from feces collected at the Sao Paulo Zoo and were also gathered from non-sedated pet or from recently dead wild animals and were also collected from museum specimens. Fractions of hair samples were stained before DNA extraction, while most samples were not. Our extraction protocol is based on a feather DNA extraction technique, based in the phenol: chloroform: isoamyl alcohol general method, with proteinase K as digestive enzyme.

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We examined the sequence, order or steps of hygienic behavior (HB) from pin-killed pupae until the removal of them by the bees. We conducted our study with four colonies of Apis mellifera carnica in Germany and made four repetitions. The pin-killing method was used for evaluation of the HB of bees. The data were collected every 2 h after perforation, totaling 13 observations. Additionally, for one hygienic colony and another non-hygienic colony, individual analyses of each dead pupa were made at every observation, including all details, steps or sequences of HB. The bees recognize the cells containing dead pupae within 2 h after perforation, initially making a hole in the capping, which is the beginning of HB. Uncapping of the dead brood cell reached maximum values from 4 to 6 h after perforation; after 24 h, practically all cells were already uncapped. Another variable, called brood partially removed, was analyzed 4 h after perforation, after the cells had been perforated, which involved uncapping, followed by partial or total removal of the brood. Maximum values of brood partially removed were found 10 h after perforation, though such cells could be found up to 48 h after perforation. The most frequent sequence of events in both colonies was: capped cell -> punctured cell. brood partially removed -> empty cell. A new model of three pairs of recessive genes (uncapping u1, u2 and remover r) was proposed in order to explain the genetic control of the HB in Apis mellifera. We recommend evaluating HB 24 h after perforation and using a correction factor to compensate for control removal levels. We found a series of details of HB, which allow a study of how various factors may affect the sequence of the activities involved in HB and investigation of the genetics that controls this process.

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We report the infestation of stingless bee nests by the mite Pyemotes tritici, which killed four colonies of Tetragonisca angustula and one colony of Frieseomelitta varia in Brazil. The first infected colony, a colony of T. angustula, came from an area between Uberlandia and Araguari, Minas Gerais. The transfer of the mites to the other colonies occurred through the transfer of infected combs and subsequent manipulations. Other colonies in the same meliponary, which had not been manipulated, were not infected. The infestation was terminated by isolating the dead colonies from the meliponary.

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We investigated hygienic behavior in 10 colonies of Plebeia remota, using the pin-killed method. After 24 h the bees had removed a mean of 69.6% of the dead brood. After 48 h, the bees had removed a mean of 96.4% of the dead brood. No significant correlation was found between the size of the brood comb and the number of dead pupae removed, and there was no apparent effect of the origin and the condition of the colony on the hygienic behavior of the bees. Plebeia remota has an efficiency of hygienic behavior superior to that of three of the other four stingless bee species studied until now.

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Amazon forests are potentially globally significant sources or sinks for atmospheric carbon dioxide. In this study, we characterize the spatial trends in carbon storage and fluxes in both live and dead biomass (necromass) in two Amazonian forests, the Biological Dynamic of Forest Fragments Project (BDFFP), near Manaus, Amazonas, and the Tapajos National Forest (TNF) near Santarem, Para. We assessed coarse woody debris (CWD) stocks, tree growth, mortality, and recruitment in ground-based plots distributed across the terra firme forest at both sites. Carbon dynamics were similar within each site, but differed significantly between the sites. The BDFFP and the TNF held comparable live biomass (167 +/- 7.6 MgC.ha(-1) versus 149 +/- 6.0 MgC.ha(-1), respectively), but stocks of CWD were 2.5 times larger at TNF (16.2 +/- 1.5 MgC.ha(-1) at BDFFP, versus 40.1 +/- 3.9 MgC.ha(-1) at TNF). A model of current forest dynamics suggests that the BDFFP was close to carbon balance, and its size class structure approximated a steady state. The TNF, by contrast, showed rapid carbon accrual to live biomass (3.24 +/- 0.22 MgC.ha(-1).a(-1) in TNF, 2.59 +/- 0.16 MgC.ha(-1).a(-1) in BDFFP), which was more than offset by losses from large stocks of CWD, as well as ongoing shifts of biomass among size classes. This pattern in the TNF suggests recovery from a significant disturbance. The net loss of carbon from the TNF will likely last 10 - 15 years after the initial disturbance (controlled by the rate of decay of coarse woody debris), followed by uptake of carbon as the forest size class structure and composition continue to shift. The frequency and longevity of forests showing such disequilibruim dynamics within the larger matrix of the Amazon remains an essential question to understanding Amazonian carbon balance.

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In 1997 we examined the prevalence of dementia among the Japanese elderly immigrants living in the Sao Paulo metropolitan area (n = 166). Herein, we followed up on these subjects for causes of death and dementia incidence. We were able to contact 108 subjects: 54 were already dead. The most common cause of death was cardiac disease. For dementia, 31.6% of the dead subjects were found to have developed dementia before they died, and 20.8% of the living subjects were demented. As for the baseline the clinical dementia rating (CDR), 20.8% of CDR 0 and 50.0% of CDR 0.5 subjects developed dementia in the dead group; whereas in the living group, 23.9% of CDR 0 and 52.6% of CDR 0.5 developed dementia. As a whole, the incidence was 34.2% per 1000 person-years. Cardiac disease as the most common cause of death was probably due to the higher prevalence of diabetes mellitus. Compared with the previous study, the lower incidence of dementia from the CDR 0.5 group may have been due to a higher mortality rate. This is the first study on the incidence of dementia in elderly Japanese immigrants in Brazil. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

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This paper presents an investigation of design code provisions for steel-concrete composite columns. The study covers the national building codes of United States, Canada and Brazil, and the transnational EUROCODE. The study is based on experimental results of 93 axially loaded concrete-filled tubular steel columns. This includes 36 unpublished, full scale experimental results by the authors and 57 results from the literature. The error of resistance models is determined by comparing experimental results for ultimate loads with code-predicted column resistances. Regression analysis is used to describe the variation of model error with column slenderness and to describe model uncertainty. The paper shows that Canadian and European codes are able to predict mean column resistance, since resistance models of these codes present detailed formulations for concrete confinement by a steel tube. ANSI/AISC and Brazilian codes have limited allowance for concrete confinement, and become very conservative for short columns. Reliability analysis is used to evaluate the safety level of code provisions. Reliability analysis includes model error and other random problem parameters like steel and concrete strengths, and dead and live loads. Design code provisions are evaluated in terms of sufficient and uniform reliability criteria. Results show that the four design codes studied provide uniform reliability, with the Canadian code being best in achieving this goal. This is a result of a well balanced code, both in terms of load combinations and resistance model. The European code is less successful in providing uniform reliability, a consequence of the partial factors used in load combinations. The paper also shows that reliability indexes of columns designed according to European code can be as low as 2.2, which is quite below target reliability levels of EUROCODE. (C) 2009 Elsevier Ltd. All rights reserved.

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The objective was to study the flow pattern in a plate heat exchanger (PHE) through residence time distribution (RTD) experiments. The tested PHE had flat plates and it was part of a laboratory scale pasteurization unit. Series flow and parallel flow configurations were tested with a variable number of passes and channels per pass. Owing to the small scale of the equipment and the short residence times, it was necessary to take into account the influence of the tracer detection unit on the RID data. Four theoretical RID models were adjusted: combined, series combined, generalized convection and axial dispersion. The combined model provided the best fit and it was useful to quantify the active and dead space volumes of the PHE and their dependence on its configuration. Results suggest that the axial dispersion model would present good results for a larger number of passes because of the turbulence associated with the changes of pass. This type of study can be useful to compare the hydraulic performance of different plates or to provide data for the evaluation of heat-induced changes that occur in the processing of heat-sensitive products. (C) 2011 Elsevier Ltd. All rights reserved.

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Among several process variability sources, valve friction and inadequate controller tuning are supposed to be two of the most prevalent. Friction quantification methods can be applied to the development of model-based compensators or to diagnose valves that need repair, whereas accurate process models can be used in controller retuning. This paper extends existing methods that jointly estimate the friction and process parameters, so that a nonlinear structure is adopted to represent the process model. The developed estimation algorithm is tested with three different data sources: a simulated first order plus dead time process, a hybrid setup (composed of a real valve and a simulated pH neutralization process) and from three industrial datasets corresponding to real control loops. The results demonstrate that the friction is accurately quantified, as well as ""good"" process models are estimated in several situations. Furthermore, when a nonlinear process model is considered, the proposed extension presents significant advantages: (i) greater accuracy for friction quantification and (ii) reasonable estimates of the nonlinear steady-state characteristics of the process. (C) 2010 Elsevier Ltd. All rights reserved.