Computational studies of the reversible domain swapping of p13suc1

A minimalist representation of protein structures using a Go- like potential for interactions is implemented to investigate the mechanisms of the domain swapping of p13suc1, a protein that exists in two native conformations: a monomer and a domain- swapped dimer formed by the exchange of a beta- strand. Inspired by experimental studies which showed a similarity of the transition states for folding of the monomer and the dimer, in this study we justify this similarity in molecular descriptions. When intermediates are populated in the simulations, formation of a domain- swapped dimer initiates from the ensemble of unfolded monomers, given by the fact that the dimer formation occurs at the folding/ unfolding temperature of the monomer ( T-f). It is also shown that transitions, leading to a dimer, involve the presence of two intermediates, one of them has a dimeric form and the other is monomeric; the latter is much more populated than the former. However, at temperatures lower than T-f, the population of intermediates decreases. It is argued that the two folded forms may coexist in absence of intermediates at a temperature much lower than T-f. Computational simulations enable us to find a mechanism, `` lock- and- dock'', for domain swapping of p13suc1. To explore the route toward dimer formation, the folding of unstructured monomers must be retarded by first locking one of the free ends of each chain. Then, the other free termini could follow and dock at particular regions, where most intrachain contacts are formed, and thus de. ne the transition states of the dimer. The simulations also showed that a decrease in the maximum distance between monomers increased their stability, which is explained based on confinement arguments. Although the simulations are based on models extracted from the native structure of the monomer and the dimer of p13suc1, the mechanism of the domain- swapping process could be general, not only for p13suc1.

Assessing the uncertainties of model estimates of primary productivity in the tropical Pacific Ocean

Depth-integrated primary productivity (PP) estimates obtained from satellite ocean color-based models (SatPPMs) and those generated from biogeochemical ocean general circulation models (BCGCMs) represent a key resource for biogeochemical and ecological studies at global as well as regional scales. Calibration and validation of these PP models are not straightforward, however, and comparative studies show large differences between model estimates. The goal of this paper is to compare PP estimates obtained from 30 different models (21 SatPPMs and 9 BOGCMs) to a tropical Pacific PP database consisting of similar to 1000 C-14 measurements spanning more than a decade (1983-1996). Primary findings include: skill varied significantly between models, but performance was not a function of model complexity or type (i.e. SatPPM vs. BOGCM); nearly all models underestimated the observed variance of PR specifically yielding too few low PP (< 0.2 g Cm-2 d(-1)) values; more than half of the total root-mean-squared model-data differences associated with the satellite-based PP models might be accounted for by uncertainties in the input variables and/or the PP data; and the tropical Pacific database captures a broad scale shift from low biomassnormalized productivity in the 1980s to higher biomass-normalized productivity in the 1990s, which was not successfully captured by any of the models. This latter result suggests that interdecadal and global changes will be a significant challenge for both SatPPMs and BOGCMs. Finally, average root-mean-squared differences between in situ PP data on the equator at 140 degrees W and PP estimates from the satellite-based productivity models were 58% lower than analogous values computed in a previous PP model comparison 6 years ago. The success of these types of comparison exercises is illustrated by the continual modification and improvement of the participating models and the resulting increase in model skill. (C) 2008 Elsevier BY. All rights reserved.

New contributions to the determination of resonance frequencies of rectangular microstrip antennas by neural networks

This paper uses artificial neural networks (ANN) to compute the resonance frequencies of rectangular microstrip antennas (MSA), used in mobile communications. Perceptron Multi-layers (PML) networks were used, with the Quasi-Newton method proposed by Broyden, Fletcher, Goldfarb and Shanno (BFGS). Due to the nature of the problem, two hundred and fifty networks were trained, and the resonance frequency for each test antenna was calculated by statistical methods. The estimate resonance frequencies for six test antennas were compared with others results obtained by deterministic and ANN based empirical models from the literature, and presented a better agreement with the experimental values.

A territorial perspective: towards the consolidation of human settlements in Latin America and the Caribbean

Includes bibliography

Descrição do conceito de deficiência a partir da mídia cinematográfica: uma análise comportamental

This work pointed out forming elements from the conception of special necessities that the media show the audience by the movies. An expression description has established special needs and they were identified as keywords on a search of movies (1994-2004) which were analyzed by two observers, according to a script. The results showed that 33 of the movies selected, 39.9% were classified in the ramacategory; 64% shows the disability as organic nature and 57% with predominant clinic diagnoses. Many labeled practices were identified (85%) and few accessibilities options (76%). In 85% of the movies the disability is said a manifestation of problems with few (58%) professionals intervention. The results are discussed by the media role on the concept formation of disabilities, offering interaction models with important role on social practice specification or unsuitable to the relation with the diversity and to the culture.

Caracterização estrutural e das interações entre a Proteína G do hRSV e potenciais inibidores

Pós-graduação em Microbiologia - IBILCE

An assessment of the economic and social impacts of climate change on the energy sector in the Caribbean

The present report assesses the economic and social impacts of climate change on the energy sector in Antigua and Barbuda, the Bahamas, Barbados, Belize, Cuba, Dominica, the Dominican Republic, Haiti, Grenada, Guyana, Jamaica, Saint Kitts and Nevis, Saint Vincent and the Grenadines, Saint Lucia, Suriname, and Trinidad and Tobago. In the study, the Artificial Neural Network methodology was employed to model the relationship between climate change and energy demand. The viability of the actions proposed were assessed using cost benefit analyses based on models from the National Renewable Energy Laboratory (NREL) of the United States of America.

Epidemiological and oral manifestations of HIV-positive patients in a specialized service in Brazil

The purpose of this study was to evaluate the prevalence of oral lesions in HIV-positive patients attending the Specialized Service for Infectious-contagious Diseases and Parasitoses of the Health Secretariat of the State of Pará (URE-DIPE/SESPA), in the city of Belém, PA, Brazil. A total of 79 HIV-positive patients (53 males and 26 females) were examined. Clinical and epidemiological evaluations were done by correlating the lesions with gender, race, chronological age, risk behavior and prevailing immune status (CD4+ cells count). Lesion location and the presence of associated factors, such as alcohol use, smoking and denture wearing, were quantified individually for each type of lesion using a diagnostic pattern based on the clinical aspects. Approximately 47% of the patients (n=37) presented some type of oral lesion. Candidiasis (28%) and periodontal disease (28%) were the most common, followed by cervical-facial lymphadenopathy (17.5%). Other lesions observed were hairy leukoplakia, melanin hyperpigmentation, ulcerative stomatitis (aphthous), herpes simplex, frictional keratosis and pyogenic granuloma. This analysis presented some relevance as to the statistical data. Concerning CD4+ cells, most lesions manifested with the reduction of the CD count. There were a larger number of HIV-positive female heterosexual patients. Alcohol and/or smoking were strongly associated with the occurrence of hairy leukoplakia in these patients. Candidiasis and periodontal disease were the most common oro-regional clinical manifestations in the patients.

Ecologia política e estratégias de sustentabilidade: uma reflexão teórica

Este artigo tem como objetivo realizar uma reflexão teórica baseada nos modelos que analisam a relação entre crescimento populacional e acesso e uso de recursos naturais, inserindo nos modelos apresentados para análise dessa relação, a dimensão da posteridade como categoria balizadora das decisões políticas acerca das estratégias possíveis de sustentabilidade. O artigo apresenta o modelo de Boserup acerca da pressão populacional sobre os recursos, as arguições sobre a liberdade, de Stuart Mill e o modelo sobre Recursos Comuns de Elinor Ostrom.

Arenas de produção de políticas públicas: a nova Política Nacional de Atenção à Saúde Mental no período de 1989 a 2001

A interação entre os Poderes Executivo e Legislativo no processo de produção de políticas públicas apresenta contornos diversificados, que variam segundo as regras inerentes ao sistema político, as estratégias adotadas por esses atores políticos e a capacidade dos grupos sociais organizados de influenciar as decisões políticas relativas a políticas públicas. Não há, portanto, um padrão único de interação entre esses Poderes no processo decisório de políticas públicas. No sistema político brasileiro o Executivo e o Legislativo são os responsáveis diretos pelo encargo estatal de editar políticas públicas, daí o objetivo deste trabalho de investigar, sob o enfoque neoinstitucionalista, as bases da interação entre esses Poderes na produção da nova política nacional de saúde mental, no período de 1989 a 2001, seu período de consolidação normativa, em meio à correlação de forças que se costuma estabelecer entre eles no processo decisório de políticas públicas. A Constituição Federal de 1988, que estabelece como um dever do Estado a formulação de políticas públicas que promovam, protejam e recuperem a saúde das pessoas, fortaleceu o papel do Congresso enquanto arena decisória de políticas públicas, mas o Executivo acaba por imprimir uma dinamicidade própria ao processo de produção de políticas públicas, fazendo uso de instrumentos institucionais diversos que podem até excluir o Parlamento do processo decisório.

A geografia dos conflitos agrários no campo brasileiro: os dados do Governo Lula

Este texto apresenta uma breve reflexão sobre a Geografia dos conflitos agrários no Brasil entre os anos 2003 e 2006, enfatizando o período do primeiro Governo de Lula da Silva. Baseiase nos dados levantados pela Comissão Pastoral da Terra – CPT, que desde 1985 vem compilando informações sobre os conflitos no campo brasileiro. A análise dos dados nos dá a dimensão das medidas mais significativas ocorridas no âmbito das políticas relativas à agricultura brasileira, sobretudo no que se refere à política de reforma agrária. A presença significativa da violência e dos conflitos no campo brasileiro evidencia a persistência da reprodução de um modelo agrário-agrícola baseado na concentração de terra, da riqueza e de poder. Demonstra, sobretudo, a resistência das populações do campo – camponeses, sem terra, indígenas, seringueiros, quilombolas, dentre outras –, impelidas a protagonizar as mais diversas lutas sociais no país para manterem suas terras. A presença dos movimentos sociais na cena política demonstra a importância da realização da Reforma Agrária no contexto do desenvolvimento da sociedade brasileira.

Diversity of eating patterns and obesity in older adults: a new challenge

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Advances in Bovine Tuberculosis Diagnosis and Pathogenesis: What Policy Makers Need to Know

The mainstay of tuberculosis diagnosis in cattle and deer has been the tuberculin skin test. Recent advances have allowed the incorporation of blood based assays to the diagnostic arsenal for both cattle and deer. Use of defined and specific antigens has allowed for improved specificity of cell mediated assays in both cattle and deer and advances in antibody tests for tuberculosis have potential for use in free-ranging and captive cervid populations. Combined use of blood-based assays with skin testing will require further understanding of the effect of skin testing on the accuracy of blood based assays. Models of experimental infection of cattle have allowed for increased understanding of natural disease pathogenesis. Differences likely exist; however, between cattle and deer in both disease distribution and primary route of inoculation in naturally infected animals.

Effects of tannery sludge application on physiological and fatty acid profiles of the soil microbial community

The impact of tannery sludge application on soil microbial community and diversity is poorly understood. We studied the microbial community in an agricultural soil following two applications (2006 and 2007) of tannery sludge with annual application rates of 0.0,2.3 and 22.6 Mg ha(-1). The soil was sampled 12 and 271 days after the second (2007) application. Community structure was assessed via a phospholipid fatty acid analysis, and the physiological profile of the soil microbial community via the Biolog method. Tannery sludge application changed soil chemical properties, increasing the soil pH and electrical conductivity as well as available P and mineral N concentrations. The higher sludge application rate changed the community structure and the physiological profile of the microbial community at both sampling dates. However, there is no clear link between community structure and carbon substrate utilization. According to the Distance Based Linear Models Analysis, the fatty acids 16:0 and 117:0 together contributed 84% to the observed PLFA patterns, whereas the chemical properties available P, mineral N, and Ca, and pH together contributed 54%. At 12 days, tannery sludge application increased the average well color development from 0.46 to 0.87 after 48 h, and reduced the time elapsed before reaching the midpoint carbon substrate utilization (s) from 71 to 44 h, an effect still apparent nine months after application of the higher sludge application rate. The dominant signature fatty acids and kinetic parameters (r and s) were correlated to the concentrations of available P. Ca, mineral N, pH and EC. (c) 2012 Elsevier B.V. All rights reserved.

Interpretation of the depths of maximum of extensive air showers measured by the Pierre Auger Observatory

To interpret the mean depth of cosmic ray air shower maximum and its dispersion, we parametrize those two observables as functions of the rst two moments of the lnA distribution. We examine the goodness of this simple method through simulations of test mass distributions. The application of the parameterization to Pierre Auger Observatory data allows one to study the energy dependence of the mean lnA and of its variance under the assumption of selected hadronic interaction models. We discuss possible implications of these dependences in term of interaction models and astrophysical cosmic ray sources.