Thermal performance of sisal fiber-cement roofing tiles for rural constructions

Roofing provides the main protection against direct solar radiation in animal housing. Appropriate thermal properties of roofing materials tend to improve the thermal comfort in the inner ambient. Nonasbestos fiber-cement roofing components reinforced with cellulose pulp from sisal (Agave sisalana) were produced by slurry and dewatering techniques, with an optional addition of polypropylene fibers. Nonasbestos tiles were evaluated and compared with commercially available asbestos-cement sheets and ceramic tiles (frequently chosen as roofing materials for animal housing). Thermal conductivity and thermal diffusivity of tiles were determined by the parallel hot-wire method, along with the evaluation of the downside surface temperature. Cement-based components reinforced with sisal pulp presented better thermal performance at room temperature (25ºC), while those reinforced with sisal pulp added by polypropylene fibers presented better thermal performance at 60ºC. Non-asbestos cement tiles provided more efficient protection against radiation than asbestos corrugated sheets.

Weekend/weekday differences in concentrations of ozone, nox, and non-methane hydrocarbon in the metropolitan area of São Paulo

Ozone and inhalable particulate matter are the major air pollutants in the Metropolitan Area of São Paulo, Brazil, a region that has more than 19 million inhabitants and approximately 7 million registered vehicles. Proximity of roadways, adjacent land use, and local circulation are just some of the factors that can affect the results of monitoring of pollutant concentrations. The so-called weekend effect (higher ozone concentrations on weekends than on weekdays) might be related to the fact that concentrations of ozone precursors, such as nitrogen oxides (NOx) and Non Methane-Hydrocarbon (NMHC), are relatively lower on weekends. This phenomenon has been reported in some areas of the United States since the 1970s. The differences between the concentrations of ozone in period of weekend and weekday, were obtained from analysis of data hourly average of CETESB for 2004, studied the precursors to the formation of troposphere ozone, the meteorological variables and traffic profile for RMSP. Because of the proximity to sources of emissions from the station Pinheiros showed higher concentrations of NO and NO² and greater variations to the periods weekend and weekday. With fewer vehicles circulating during the weekend, and consequently less emission of pollutants, it has cleaner air and less concentration of NO and NO², there is the ideal setting to the formation of troposphere ozone, despite the lower concentration of NO². The proximity with the source emissions, aided by the increased availability of solar radiation and the presence of ozone precursors, were factors conditions for the occurrence of weekend effect.

Albedo à superfície a partir de imagens Landsat 5 em áreas de cana-de-açúcar e cerrado

Propôs-se, neste trabalho, estimar dados de albedo à superfície terrestre usando-se o sensor Thematic Mapper (TM) do satélite LANDSAT 5 e compará-lo com dados de duas estações agrometeorológicas localizadas em região de Cerrado e a outra em cultivo da cana-de-açúcar. A região de estudo está localizada no município de Santa Rita do Passa Quatro, SP, Brasil. Para a realização do estudo obtiveram-se seis imagens orbitais do satélite Landsat 5 sensores TM, na órbita 220 e ponto 75, nas datas de 22/02, 11/04, 29/05, 01/08, 17/08 e 21/11, todas do ano de 2005, a que correspondem os dias juliano de 53, 101, 149, 213, 229 e 325, respectivamente. As correções geométricas para as imagens foram realizadas e geradas as cartas de albedo. O algoritmo SEBAL estimou satisfatoriamente os valores de albedo de superfícies sobre áreas de cerrado e de cana-de-açúcar, na região de Santa Rita do Passa Quatro, SP, consistentes com observações realizadas do albedo à superfície.

Study of the equatorial Atlantic Ocean mixing layer using a one-dimensional turbulence model

The General Ocean Turbulence Model (GOTM) is applied to the diagnostic turbulence field of the mixing layer (ML) over the equatorial region of the Atlantic Ocean. Two situations were investigated: rainy and dry seasons, defined, respectively, by the presence of the intertropical convergence zone and by its northward displacement. Simulations were carried out using data from a PIRATA buoy located on the equator at 23º W to compute surface turbulent fluxes and from the NASA/GEWEX Surface Radiation Budget Project to close the surface radiation balance. A data assimilation scheme was used as a surrogate for the physical effects not present in the one-dimensional model. In the rainy season, results show that the ML is shallower due to the weaker surface stress and stronger stable stratification; the maximum ML depth reached during this season is around 15 m, with an averaged diurnal variation of 7 m depth. In the dry season, the stronger surface stress and the enhanced surface heat balance components enable higher mechanical production of turbulent kinetic energy and, at night, the buoyancy acts also enhancing turbulence in the first meters of depth, characterizing a deeper ML, reaching around 60 m and presenting an average diurnal variation of 30 m.

Effect of ionizing radiation on rat parotid gland

A common side effect of radiotherapy used in the treatment of oral cancer is the occurrence of structural and physiological alterations of the salivary glands due to exposure to ionizing radiation, as demonstrated by conditions such as decreased salivary flow. The present study evaluated ultrastructural alterations in the parotid glands of rats receiving a fractionated dose (1,500-cGy) of radiation emitted by a Cesium-137 source and rats that were not subjected to ionizing radiation. After sacrifice, the parotid glands were removed and examined by transmission electron microscopy. Damage such as cytoplasmic vacuolization, dilatation of the endoplasmic reticulum and destruction of mitochondria, as well as damage to the cellular membrane of acinar cells, were observed. These findings lead to the conclusion that ionizing radiation promotes alterations in the glandular parenchyma, and that these alterations are directly related to the dose level of absorbed radiation. Certain phenomena that appear in the cytoplasm and nuclear material indicate that ionizing radiation causes acinar cell death (apoptosis).

Dose de exposição radiométrica de granitos do estado de Rondônia, Brasil

Este trabalho avaliou a concentração dos radioelementos K, eU e eTh em amostras de granitos do Estado de Rondônia, Brasil. A análise estatística dos dados obtidos indicou que eles seguem distribuições lognormais. Os valores modais encontrados correspondem a cerca de 11% para K, 29 ppm para eU e 85 ppm para eTh. Correlações diretas significativas foram determinadas entre as concentrações dos três radioelementos, isto é, r = 0,71 (entre K e eU), r = 0,72 (entre K e eTh)e r = 0,72 (entre eU e eTh), sugerindo que são congruentes os processos de seu acúmulo nos minerais das rochas analisadas. Os dados de concentração permitiram estimar a taxa de dose absorvida de radiação no ar acima de 1 m do nível do terreno, a qual também segue uma distribuição lognormal, com valor modal de 2,7 mSv/ano, que é ligeiramente superior à média global de 2,4 mSv/ano. Os resultados obtidos também permitiram avaliar, do ponto de vista radiométrico, se os granitos analisados são adequados para emprego como revestimento em construção civil.

Electrochemical and photocatalytic reactions of polycyclic aromatic hydrocarbons investigated by raman spectroscopy

This paper presents the study of photochemical behavior of polycyclic aromatic hydrocarbons (PAHs), potential pollutants in secondary reactions in aerosols, through Raman spectroscopy compared with its electrochemical behavior. The PAHs studied include pyrene, anthracene, phenanthrene and fluorene. These were adsorbed onto TiO2 and irradiated with ultraviolet light (254 nm). Their electrochemical oxidation was studied by in situ Surface-enhanced Raman Scattering (SERS) and led to the formation of carbonyl-containing products. Oxidized intermediates bearing the C=O group were also formed during photodegradation. The joint analysis of the photodegradation data with those produced by electrochemical means - using spectroscopic techniques for the identification and characterization of the products - revealed the formation of identical products for anthracene, but not for pyrene. A reasonable explanation for this difference in results is that photochemical and electrochemical oxidation reactions proceed via different mechanisms. While photocatalytic degradation over TiO2 is initiated by hydroxyl radicals, electrochemical oxidation is initiated by the direct electron transfer from adsorbed PAH to the electrode, generating PAH cation radicals that undergo subsequent reactions.

Molecular phylogeny of advanced snakes (Serpentes, Caenophidia) with an emphasis on South American Xenodontines: a revised classification and descriptions of new taxa

We present a molecular phylogenetic analysis of caenophidian (advanced) snakes using sequences from two mitochondrial genes (12S and 16S rRNA) and one nuclear (c-mos) gene (1681 total base pairs), and with 131 terminal taxa sampled from throughout all major caenophidian lineages but focussing on Neotropical xenodontines. Direct optimization parsimony analysis resulted in a well-resolved phylogenetic tree, which corroborates some clades identified in previous analyses and suggests new hypotheses for the composition and relationships of others. The major salient points of our analysis are: (1) placement of Acrochordus, Xenodermatids, and Pareatids as successive outgroups to all remaining caenophidians (including viperids, elapids, atractaspidids, and all other "colubrid" groups); (2) within the latter group, viperids and homalopsids are sucessive sister clades to all remaining snakes; (3) the following monophyletic clades within crown group caenophidians: Afro-Asian psammophiids (including Mimophis from Madagascar), Elapidae (including hydrophiines but excluding Homoroselaps), Pseudoxyrhophiinae, Colubrinae, Natricinae, Dipsadinae, and Xenodontinae. Homoroselaps is associated with atractaspidids. Our analysis suggests some taxonomic changes within xenodontines, including new taxonomy for Alsophis elegans, Liophis amarali, and further taxonomic changes within Xenodontini and the West Indian radiation of xenodontines. Based on our molecular analysis, we present a revised classification for caenophidians and provide morphological diagnoses for many of the included clades; we also highlight groups where much more work is needed. We name as new two higher taxonomic clades within Caenophidia, one new subfamily within Dipsadidae, and, within Xenodontinae five new tribes, six new genera and two resurrected genera. We synonymize Xenoxybelis and Pseudablabes with Philodryas; Erythrolamprus with Liophis; and Lystrophis and Waglerophis with Xenodon.

Magnetic fields and acute lymphoblastic leukemia in children: a systematic review of case-control studies

Leukemia incidence in children has increased worldwide in recent decades, particularly due to the rise in acute lymphoblastic leukemia. Studies have associated exposure to non-ionizing radiation generated by low frequency magnetic fields with childhood leukemia. The current article reviews the case-control studies published on this subject. Of 152 articles tracked in different databases, ten studies from North America, Asia, and Europe met the defined selection criteria, with patients diagnosed from 1960 to 2004. Methodological limitations were observed in these articles, including difficulties with the procedures for assessing exposure. An association may exist between exposure to low frequency magnetic fields and acute lymphoblastic leukemia in children, but this association is weak, preventing the observation of consistency in the findings. Future studies from a wider range of geographic regions should focus on the analysis of acute lymphoblastic leukemia, which is the subtype with the greatest impact on the increasing overall incidence of childhood leukemia.

Qualidade de luz na biometria e anatomia foliar de plântulas de Cattleya loddigesii L. (Orchidaceae) micropropagadas

A qualidade de luz pode alterar a morfogênese das plantas por meio de uma série de processos mediados por receptores de luz, principalmente na região do vermelho e azul. O objetivo do presente estudo foi verificar alterações anatômicas foliares e características biométricas de Cattleya loddigesii 'Tipo', cultivadas in vitro, sob diferentes malhas coloridas com nível de radiação de 50% de sombreamento. Plântulas oriundas de autopolinização e sementes germinadas in vitro, com aproximadamente 1,0cm de comprimento e com raízes, foram inoculadas em meio WPM e submetidas a diferentes condições de incubação. Testou-se o efeito de sombrites coloridos (vermelho e azul) sobre os frascos cultivados em casa de vegetação (CV) e sala de crescimento (SC), além dos tratamentos, nos dois ambientes, sem utilização das telas coloridas. A avaliação foi efetuada 180 dias após inoculação. Com os resultados obtidos, observou-se que o ambiente de cultivo promove alterações anatômicas e biométricas em plântulas de Cattleya loddigesii 'Tipo' micropropagadas. As alterações promovidas pelo cultivo em luz natural evidenciam maior capacidade fotossintética, por meio de maior diferenciação dos tecidos clorofilianos, promovendo uma superfície foliar anatomicamente adaptada à fase de aclimatização.

Controle de vetores utilizando mosquitos geneticamente modificados

Formas químicas de controle de mosquitos vetores são ineficazes, levando ao desenvolvimento de novas estratégias. Assim, foi realizada revisão das estratégias de controle genético de populações de mosquitos vetores baseada na técnica do inseto estéril. Uma delas consiste na liberação de machos esterilizados por radiação, a outra, na integração de um gene letal dominante associado a um promotor específico de fêmeas imaturas. Entre as vantagens sobre outras técnicas biológicas e químicas de controle de vetores estão: alta especificidade, não prejudicial ao meio ambiente, baixo custo de produção e alta eficácia. O uso desta técnica de modificação genética pode vir a ser uma importante ferramenta do manejo integrado de vetores

Cart??o do cidad??o

O pagamento dos benef??cios sociais, efetuado no guich?? de caixa das ag??ncias, era um processo lento e oneroso ao cidad??o e ?? CAIXA. Envolvia elevado quantitativo de atendentes e significativo tempo para a execu????o de rotinas inerentes, principalmente no que diz respeito ?? qualifica????o e ?? identifica????o do trabalhador, ao tratamento da documenta????o e ?? coleta de assinatura no documento de pagamento, gerando elevado custo operacional. Em 1995, a CAIXA lan??ou o Cart??o do Trabalhador, que permitia o acompanhamento de lan??amentos do Fundo de Garantia do Tempo de Servi??o (FGTS) e acesso ao saldo de cotas de sua participa????o no Programa de Integra????o Social (PIS), mas n??o tinha a funcionalidade de saque de benef??cios e n??o atendia os benefici??rios do Abono Salarial e do Seguro- Desemprego. A necessidade de aperfei??oar e integrar os processos de atendimento e pagamento desses produtos sociais levou ?? cria????o do Cart??o do Cidad??o, que proporcionou melhoria significativa na qualidade do atendimento ao cidad??o e minimizou os custos operacionais

Sistema de c??lculo de acr??scimos legais: SICALC

Efetuar o c??lculo dos acr??scimos legais para uma determinada data, mediante o fornecimento dos dados do cr??dito tribut??rio e/ou apurar o valor devedor ou credor, saldo, resultante da associa????o de pagamentos e cr??ditos tribut??rios. A aplica????o visa facilitar e agilizar o atendimento ao p??blico em geral e subsidiar os c??lculos no acompanhamento de processos fiscais nas reparti????es da SRF. Minimizar o fluxo de pessoas a SRF, permitindo que qualquer usu??rio que tenha tributos j?? vencidos ou a vencer (quotas), possa utilizar o sistema, bastando para isso, efetuar uma baixa dos programas da Internet e realizar os seus pr??prios c??lculos, gerando automaticamente o Documento de Arrecada????o Federal - DARF para ser recolhido na rede arrecadora sem a necessidade de se dirigir ?? SRF

Presta????o de contas ordin??ria anual: relat??rio de gest??o do exerc??cio de 2010

Relat??rio de Gest??o do exerc??cio de 2010 apresentado aos ??rg??os de controle interno e externo como presta????o de contas anual que a ENAP est?? obrigada nos termos do art. 70 da Constitui????o Federal, elaborado de acordo com as disposi????es da IN TCU n?? 63/2010, da DN TCU n?? 107/2010, da Portaria TCU n?? 277/2010 e das orienta????es do ??rg??o de controle interno (Portaria CGU n?? 2546/2010)

Alterações microclimáticas causadas pelo uso de tela plástica

Com o objetivo de caracterizar as alterações microclimáticas provocadas pelo uso de tela plástica na agricultura, foi desenvolvido um experimento com alface, em área de cultivo agrícola, em Alegre - ES (latitude 20º45 S, longitude 41º28 W e altitude 150 m), no período de setembro a dezembro de 1996. Foram utilizados sombreamentos de 0; 30; 50, e 70%, segundo especificação comercial. Os resultados mostraram que a tela com especificação comercial de 50% de sombreamento provocou uma atenuação média de 41% na radiação solar global, ocorrendo, no entanto, uma flutuação significativa ao longo do dia em função do movimento aparente do sol. A cobertura com a tela plástica não provocou alterações significativas da temperatura e umidade relativa do ar. Em relação à temperatura do solo, foi possível verificar uma atenuação com o aumento do sombreamento.