Early weaning impairs body composition in male mice

O presente estudo objetivou avaliar o efeito do desmame precoce sobre a composição corporal e sobre parâmetros indicativos do estado nutricional de camundongos. O grupo experimental consistiu de camundongos Swiss Webster, machos, desmamados precocemente (14º dia de vida) e alimentados com ração apropriada para roedores em crescimento até o 21º dia pós-natal (grupo DESM). O grupo controle consistiu de camundongos amamentados até o 21º dia pós-natal (grupo CON). Todos os animais foram sacrificados no 21º dia de vida. O grupo DESM apresentou redução da concentração e conteúdo hepático e muscular de proteínas, da concentração cerebral de proteínas, da concentração e conteúdo cerebral de DNA e da razão proteína/RNA hepática e muscular (p<0,05). Quanto à composição corporal, o grupo DESM apresentou maior conteúdo de umidade, maior percentual de umidade e lipídios e menor conteúdo e percentual de cinzas e proteína na carcaça (p<0,05). Os resultados indicam que o desmame precoce acarreta em prejuízo à composição corporal e a parâmetros indicativos do estado nutricional, o que pode estar relacionado ao retardo do processo de maturação química. Os dados do presente estudo podem contribuir para o entendimento da influência da alimentação com fórmulas infantis sobre a composição corporal e sobre o estado nutricional.

Necessidade energética estimada, valor energético e adequação de macronutrientes da alimentação dos idosos de Fortaleza/CE

O objetivo deste estudo foi verificar a necessidade energética estimada, o valor energético e a adequação de macronutrientes da alimentação dos idosos de Fortaleza. Este estudo é epidemiológico, transversal, com coleta de dados primários. As variáveis de estudo foram: necessidade energética estimada, valor energético da alimentação e adequação dos macronutrientes da alimentação. O inquérito alimentar utilizado para obtenção do valor energético da alimentação (VEA) foi o recordatório de 24 horas (R24). O cálculo da necessidade energética estimada (NEE) da população foi realizado a partir das equações propostas pelo Institute of Medicine (IOM, 2002). A adequação dos macronutrientes da alimentação foi verificada a partir dos valores propostos nos intervalos da distribuição aceitável de macronutrientes (IOM, 2002). Foi avaliada a alimentação de 458 idosos (153 homens e 305 mulheres). A média etária dos idosos foi 70,9 anos (DP= 7,9 anos). O valor energético médio da alimentação dos homens foi superior ao das mulheres. O valor energético médio da alimentação dos idosos foi inferior ao valor médio da necessidade energética estimada, tanto dos homens como das mulheres (p=0,000). Quanto à proporção de proteína da alimentação, a maioria dos idosos (91,7 por cento), apresentou valores adequados. A proporção de carboidratos da alimentação, também se mostrou adequada na maioria das dietas (59,8 por cento). O consumo de alimentação com adequada proporção de lipídio foi verificado em 53,9 por cento dos idosos. Sendo assim, conclui-se que os idosos de Fortaleza apresentam alimentação com valor energético insuficiente em relação à necessidade energética estimada para os mesmos

Alimentação saudável: percepções dos educadores de instituições infantis

Objetivo: Analisar as percepções dos educadores sobre a alimentação suadável no ambito escolar. Método: Estudo transversal de abordagem qualitativa no qual se utilizou o Discurso do Sujeito Coletivo (DSC), técnica baseada nas representações sociais, que permitiu a organização e tabulação de dados de natureza verbal, obtidos por meio de entrevistas com 78 educadores de 8 instituições infantis públicas do município de Jandira, São Paulo. Resultados: A alimentação saudável para crianças , sobre o ponto de vista destes profissionais, foi percebida a partir de diferentes dimensões como: a variedade e a diversidadade da alimentação; a quantidade e qualidade adequada, que atendesse às necessidades biológicas e às preferências alimentares; de consistência adequada, que fosse natural e oferecida nos horários certos. Muitos dos fundamentos que compõem uma alimentação saudável foram citados, porém verificou-se que algumas questões importantes não foram lembradas, como"a procedência e a preparação dos alimentos, a realização das refeições em ambientes calmos e a satisfação das necessidades emocionais e sociais. Ressaltando ainda que, dentre os itens comtemplados, alguns apresentaram contradições e distorções, como as questões das preferências versus gostos alimentares e da consistência. Conclusão: A maioria das percepções dos educadores sobre a alimentação saudável observadas nos discursos demostraram-se inadequadas quando comparadas aos parametros da promoção dos hábitos alimentares para as crianças. Práticas e percepções estas, que podem, em alguns casos, influenciar a conduta destes profissionais no momento das atividades de alimentação.

Aspectos dietéticos das refeições oferecidas por empresas participantes do Programa de Alimentação do Trabalhador na Cidade de São Paulo, Brasil

Resumo: OBJETIVO: Avaliar os aspectos dietéticos das refeições oferecidas por empresas inscritas no Programa de Alimentação do Trabalhador (PAT) na Cidade de São Paulo, Brasil, em relação às recomendações nutricionais do Guia Alimentar para a População Brasileira do Ministério da Saúde. MÉTODOS:Foram investigadas 72 empresas, caracterizadas conforme setor (indústria, serviços ou comércio), porte (micro, pequenas, médias ou grandes), modalidade do PAT (autogestão, gestão terceirizada do tipo refeição transportada ou gestão terceirizada do tipo preparo e distribuição de refeição na empresa) e supervisão de nutricionista (sim ou não). A quantidade per capita dos alimentos foi determinada nos cardápios de 3 dias de almoço, jantar e ceia. O valor nutricional das refeições foi definido com base nas variáveis energia, carboidrato, proteína, gorduras totais, gordura poliinsaturada, gordura saturada, gordura trans, açúcares livres, colesterol e frutas e hortaliças. RESULTADOS:A maioria dos cardápios teve baixa oferta de frutas e hortaliças (63,9%) e gordura poliinsaturada (83,3%) e excesso de gorduras totais (47,2%) e colesterol (62,5%). O agrupamento 2, composto principalmente por empresas de médio e grande porte do setor industrial e de serviços, com gestão terceirizada e supervisão de nutricionista, teve, em média, refeições com maior valor energético (P < 0,001), maior porcentagem de gorduras poliinsaturadas (P < 0,001), maior quantidade de colesterol (P = 0,015) e maior quantidade de frutas e hortaliças (P < 0,001) do que o agrupamento 1, composto por micro e pequenas empresas do setor de comércio, tendo autogestão como modalidade e sem supervisão de nutricionista. Quanto à adequação dos cardápios oferecidos às metas do Guia Alimentar para a População Brasileira, as refeições do agrupamento 2 foram mais adequadas em relação à oferta de frutas e hortaliças (P < 0,001). ) Em contrapartida, o agrupamento 1 apresentou maior adequação da quantidade de colesterol (P = 0,05). CONCLUSÕES: É necessária uma ação mais direcionada aos gestores de empresas e aos responsáveis pelas unidades de alimentação e nutrição, principalmente no grupo de empresas que não tem a supervisão de nutricionista

Classification of breast masses using a committee machine of artificial neural networks

This work proposes a new approach using a committee machine of artificial neural networks to classify masses found in mammograms as benign or malignant. Three shape factors, three edge-sharpness measures, and 14 texture measures are used for the classification of 20 regions of interest (ROIs) related to malignant tumors and 37 ROIs related to benign masses. A group of multilayer perceptrons (MLPs) is employed as a committee machine of neural network classifiers. The classification results are reached by combining the responses of the individual classifiers. Experiments involving changes in the learning algorithm of the committee machine are conducted. The classification accuracy is evaluated using the area A. under the receiver operating characteristics (ROC) curve. The A, result for the committee machine is compared with the A, results obtained using MLPs and single-layer perceptrons (SLPs), as well as a linear discriminant analysis (LDA) classifier Tests are carried out using the student's t-distribution. The committee machine classifier outperforms the MLP SLP, and LDA classifiers in the following cases: with the shape measure of spiculation index, the A, values of the four methods are, in order 0.93, 0.84, 0.75, and 0.76; and with the edge-sharpness measure of acutance, the values are 0.79, 0.70, 0.69, and 0.74. Although the features with which improvement is obtained with the committee machines are not the same as those that provided the maximal value of A(z) (A(z) = 0.99 with some shape features, with or without the committee machine), they correspond to features that are not critically dependent on the accuracy of the boundaries of the masses, which is an important result. (c) 2008 SPIE and IS&T.

Cultivo da microalga marinha Chaetoceros calcitrans (BACILLARIOPHYCEAE) utilizando diferentes tipos de água marinha artificial

The use of microalgae as live food to a wide variety of organisms is one of the most important aspects in aquaculture. Several commercial formulations have been available in the marine aquarium market in order to prepare artificial sea water (ASW). The present study accounted microalgae Chaetoceros calcitrans performance cultured using different ASW in comparison to natural seawater(NSW). it was carried out using red Sea, Coralife and oceanic, three different ASW brands and NSW as control. nonaerated cultures were grew in 400 mL with Conwy culture medium with five replicates each under defined conditions. All cultures began with an algal inoculum of 208.000 cells/mL. a 5-mL aliquot was removed daily from each culture for cells counts. data obtained using polynomial regression test demonstrated that all ASW brands reached higher algal density rates than the one with NSW, though the three ASW brands were significantly heterogeneous. C. calcitrans raised with oceanic and red Sea brands showed similar growth rates and both were higher than Coralife brand. the results suggest that all three ASW brands studied can be used in the culture of this microalgae specie.

Artificial Lighting as a Vector Attractant and Cause of Disease Diffusion

BACKGROUND: Traditionally, epidemiologists have considered electrification to be a positive factor. In fact, electrification and plumbing are typical initiatives that represent the integration of an isolated population into modern society, ensuring the control of pathogens and promoting public health. Nonetheless, electrification is always accompanied by night lighting that attracts insect vectors and changes people's behavior. Although this may lead to new modes of infection and increased transmission of insect-borne diseases, epidemiologists rarely consider the role of night lighting in their surveys. OBJECTIVE: We reviewed the epidemiological evidence concerning the role of lighting in the spread of vector-borne diseases to encourage other researchers to consider it in future studies. DISCUSSION: We present three infectious vector-borne diseases-Chagas, leishmaniasis, and malaria-and discuss evidence that suggests that the use of artificial lighting results in behavioral changes among human populations and changes in the prevalence of vector species and in the modes of transmission. CONCLUSION: Despite a surprising lack of studies, existing evidence supports our hypothesis that artificial lighting leads to a higher risk of infection from vector-borne diseases. We believe that this is related not only to the simple attraction of traditional vectors to light sources but also to changes in the behavior of both humans and insects that result in new modes of disease transmission. Considering the ongoing expansion of night lighting in developing countries, additional research on this subject is urgently needed.

Detection of Ureaplasma diversum in bovine semen straws for artificial insemination

Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[06/56855-0]

Artificial molecular quantum rings under magnetic field influence

The ground states of a few electrons confined in two vertically coupled quantum rings in the presence of an external magnetic field are studied systematically within the current spin-density functional theory. Electron-electron interactions combined with inter-ring tunneling affect the electronic structure and the persistent current. For small values of the external magnetic field, we recover the zero magnetic field molecular quantum ring ground state configurations. Increasing the magnetic field many angular momentum, spin, and isospin transitions are predicted to occur in the ground state. We show that these transitions follow certain rules, which are governed by the parity of the number of electrons, the single-particle picture, Hund's rules, and many-body effects. (C) 2009 American Institute of Physics. [doi:10.1063/1.3223360]

Making solar fuels by artificial photosynthesis

In order for solar energy to serve as a primary energy source, it must be paired with energy storage on a massive scale. At this scale, solar fuels and energy storage in chemical bonds is the only practical approach. Solar fuels are produced in massive amounts by photosynthesis with the reduction of CO(2) by water to give carbohydrates but efficiencies are low. In photosystem II (PSII), the oxygen-producing site for photosynthesis, light absorption and sensitization trigger a cascade of coupled electron-proton transfer events with time scales ranging from picoseconds to microseconds. Oxidative equivalents are built up at the oxygen evolving complex (OEC) for water oxidation by the Kok cycle. A systematic approach to artificial photo synthesis is available based on a ""modular approach"" in which the separate functions of a final device are studied separately, maximized for rates and stability, and used as modules in constructing integrated devices based on molecular assemblies, nanoscale arrays, self-assembled monolayers, etc. Considerable simplification is available by adopting a ""dyesensitized photoelectrosynthesis cell"" (DSPEC) approach inspired by dye-sensitized solar cells (DSSCs). Water oxidation catalysis is a key feature, and significant progress has been made in developing a single-site solution and surface catalysts based on polypyridyl complexes of Ru. In this series, ligand variations can be used to tune redox potentials and reactivity over a wide range. Water oxidation electrocatalysis has been extended to chromophore-catalyst assemblies for both water oxidation and DSPEC applications.

Correlation of Modified Natural Rubber Properties by Artificial Neural Networks

Natural rubber (NR) is a raw material largely used by the modern industry; however, it is common that chemical modifications must be made to NR in order to improve properties such as hydrophobicity or mechanical resistance. This work deals with the correlation of properties of NR modified with dimethylaminoethylmethacrylate or methylmethacrylate as grafting agents. Dynamic-mechanical behavior and stress/strain relations are very important properties because they furnish essential characteristics of the material such as glass transition temperature and rupture point. These properties are concerned with different physical principles; for this reason, normally they are not related to each other. This work showed that they can be correlated by artificial neural networks (ANN). So, from one type of assay, the properties that as a rule only could be obtained from the other can be extracted by ANN correlation. POLYM. ENG. SCI., 49:499-505, 2009. (c) 2009 Society of Plastics Engineers

Optimization of Heat Treatment Profiles Applied to Nanometric-Scale Nb(3)Sn Wires With Cu-Sn Artificial Pinning Centers

Nb(3)Sn is one of the most used superconducting materials for applications in high magnetic fields. The improvement of the critical current densities (J(c)) is important, and must be analyzed together with the optimization of the flux pinning acting in the material. For Nb(3)Sn, it is known that the grain boundaries are the most effective pinning centers. However, the introduction of artificial pinning centers (APCs) with different superconducting properties has been proved to be beneficial for J(c). As these APCs are normally in the nanometric-scale, the conventional heat treatment profiles used for Nb(3)Sn wires cannot be directly applied, leading to excessive grain growth and/or increase of the APCs cross sections. In this work, the heat treatment profiles for Nb(3)Sn superconductor wires with Cu(Sn) artificial pinning centers in nanometric-scale were analyzed in an attempt to improve J(c) . It is described a methodology to optimize the heat treatment profiles in respect to diffusion, reaction and formation of the superconducting phases. Microstructural, transport and magnetic characterization were performed in an attempt to find the pinning mechanisms acting in the samples. It was concluded that the maximum current densities were found when normal phases (due to the introduction of the APCs) are acting as main pinning centers in the global behavior of the Nb(3)Sn superconducting wire.

Heat treatment influence on the superconducting properties of nanometric-scale Nb(3)Sn wires with Cu-Sn artificial pinning centers

Since the discovery of Nb(3)Sn superconductors many efforts have been expended to improve the transport properties in these materials. In this work, the heat treatment profiles for Nb(3)Sn superconductor wires with Cu(Sn) artificial pinning centers (APCs) with nanometric-scale sizes were analyzed in an attempt to improve the critical current densities and upper critical magnetic field. The methodology to optimize the heat treatment profiles in respect to the diffusion, reaction and formation of the superconducting phases is described. Microstructural characterization, transport and magnetic measurements were performed in an attempt to relate the microstructure to the pinning mechanisms acting in the samples. It was concluded that the maximum current densities occur due to normal phases (APCs) that act as the main pinning centers in the global behavior of the Nb(3)Sn superconducting wire. The APC technique was shown to be very powerful because it permitted mixing of the pinning mechanism. This achievement was not possible in other studies in Nb(3)Sn wires reported up to now.

EIS study of Ti-23Ta alloy in artificial saliva

Although titanium and Ti-6Al-4V alloy have been widely used as dental materials, possible undesirable effects such as cytotoxic reactions and neurological disorder due to metal release led to the development of more corrosion resistant and V and Al free titanium alloys, containing Nb, Zr, Mo and Ta atoxic elements. Fluoride containing products used in the prevention of plaque formation and dental caries can affect the stability of the passive oxide films formed on the Ti alloys. In this work, the corrosion behaviour of the new Ti-23Ta alloy has been evaluated in artificial saliva of different pH and fluoride concentration using electrochemical impedance spectroscopy. Electrochemical impedance spectroscopy study showed that the oxide film formed on the alloy in artificial saliva consists of an inner compact film and an outer porous layer. The corrosion resistance of Ti-23Ta alloy which is reduced by increasing F concentration or decreasing pH is related to the resistance of the inner compact layer. The presence of fluoride and low pH of the saliva enhance the porosity of the oxide film and its dissolution.