112 resultados para Perm


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Pesticide exposure during brain development could represent an important risk factor for the onset of neurodegenerative diseases. Previous studies investigated the effect of permethrin (PERM) administered at 34 mg/kg, a dose close to the no observable adverse effect level (NOAEL) from post natal day (PND) 6 to PND 21 in rats. Despite the PERM dose did not elicited overt signs of toxicity (i.e. normal body weight gain curve), it was able to induce striatal neurodegeneration (dopamine and Nurr1 reduction, and lipid peroxidation increase). The present study was designed to characterize the cognitive deficits in the current animal model. When during late adulthood PERM treated rats were tested for spatial working memory performances in a T-maze-rewarded alternation task they took longer to choose for the correct arm in comparison to age matched controls. No differences between groups were found in anxiety-like state, locomotor activity, feeding behavior and spatial orientation task. Our findings showing a selective effect of PERM treatment on the T-maze task point to an involvement of frontal cortico-striatal circuitry rather than to a role for the hippocampus. The predominant disturbances concern the dopamine (DA) depletion in the striatum and, the serotonin (5-HT) and noradrenaline (NE) unbalance together with a hypometabolic state in the medial prefrontal cortex area. In the hippocampus, an increase of NE and a decrease of DA were observed in PERM treated rats as compared to controls. The concentration of the most representative marker for pyrethroid exposure (3-phenoxybenzoic acid) measured in the urine of rodents 12 h after the last treatment was 41.50 µ/L and it was completely eliminated after 96 h.

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Os autores apresentam, os resultados de um inquérito clínico-nutricional e antropométrico realizado no período 1965 a 1967, em 11.283 indivíduos residentes nas zonas rural e urbana de três Estados do nordeste brasileiro (Alagcas, Rio Grande do Norte e Pernambuco), com o objetivo de estudar o estado nutricional de populações residentes em áreas endêmicas de Esquistossomose mansônica. Chamam a atenção para a freqüência relativamente baixa de manifestações clínicas de doenças carenciais, apesar de tratar-se de região cujos baixos padrões sociais e econômicos são bastante conhecidos, sugerindo que a maioria dos indivíduos deve apresentar deficiência nutricional apenas a nível bioquímico. Dentre os sinais de doença, carencial pesquisados, foram registrados com maior freqüência: estomatite angular, cicatrizes das comissuras labiais, atrofia das papilas linguais, gengivite, dermatite seborreica naso-labial e dermatite pelagrosa. De um modo geral, as manifestações clínicas de doença carencial pareciam incidir com maior freqüência entre os indivíduos parasitados pelo S. mansoni. embora não tenham sido encontrados resultados estatisticamente significativos. Os níveis de hemoglobina, pesquisados apenas em população rural do Estado de Pernambuco (Município de São Lourenço), foram muito baixos, não havendo, contudo, diferença estatisticamente significante entre crianças exibindo manifestações clínicas de carência duplamente parasitadas, e aquelas apenas portadoras de esquistossomose. Estudo antropométrico sumário, realizado no grupo etárío de 1 a 12 anos. e baseado na tomada de pese e altura, não revelou diferença estatisticamente significativa, entre crianças exibindo ou não doença carencial, e/ou ccm e sem Esquistossomose, contrariando achados de outros autores, e para cuja explicação pode ser invocado o pequeno número de formas graves (hepato-esplênicas) encontradas no campo, nesse grupo de idade. Os resultados do presente trabalho, por tratar-se de estudo preliminar, não permitem inferir conclusões definitivas, perém reforçam a suposição do provável papel desempenhado pela desnutrição na evolução da Esquistossomose mansônica, sugerindo a necessidade de continuação desses estudos, para uma melhor compreensão dos aspectos nutricionais das relações hospedeiro-parasito, nessa helmintose.

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Så som är fallet för många andra stater, kan vissa delar av den ryska förvaltningen ännu utvecklas för att till fullo uppfylla internationella standarder. Internationella fördragsorgan som övervakar förverkligandet i Ryssland av fördrag om mänskliga rättigheter framför ibland kritiska anmärkningar om den demokratiska utvecklingen i Ryssland. Enskilda fall där politiska rättigheter möjligen kränkts av ryska myndigheter har utan tvivel placerat Ryssland i fokus för internationell media. Exempel på sådana fall är mordet på journalisten Anna Politkovskaya, Sergei Magnitskys död i fängelse och fängslandet av medlemmarna i "Pussy Riot”. Likväl anser författaren av denna studie att politiska rättigheter i Ryssland förverkligas inom rimliga gränser och i enlighet med internationell människorättslagstiftning. Denna studie fokuserar på förverkligandet av den individuella rättigheten att delta i det politiska beslutsfattandet i Ryssland genom andra mekanismer för deltagande än val och folkomröstningar. Studien utgörs av en sammanställning av forskningsartiklar som har publicerats i olika internationella tidskrifter. Sammanställningen föregås av ett fristående inledande kapitel. Författaren koncentrerar sig på frågan om Rysslands invånare ges effektiva möjligheter att delta i handhavandet av allmänna angelägenheter och om det finns användbara rättsmedel till hands för skydd av de politiska rättigheterna. Författaren tar sig an en juridisk analys av rysk lagstiftning gällande olika sätt för direkt deltagande i beslutsfattande samt analyserar rättsfall angående direkt deltagande från domstolarna i Moskva, Perm Krai och Sverdlovsk Oblast. Denna studie använder sig även av en rättshistorisk infallsvinkel för att visa på den positiva dynamiken hos den historiska utvecklingen beträffande d e väsentligaste plattformarna för offentligt deltagande. Det bevisas att rysk lagstiftning som garanterar rätten att delta i beslutsfattande är väl utvecklad i enlighet med internationella människorättsfördrag, och att åtminstone domstolarna i de utvalda ryska områdena fattar beslut som stöder deltaganderättigheter som eventuellt kränkts av myndigheter inom den verkställande makten. Författaren kommer till den slutsatsen att de i denna studie inkluderade enskilda dokumenterade händelserna gällande administrativ felbehandling inte nödvändigtvis tillåter den direkta slutsatsen att det begås systematiska och grova kränkningar av medborgares deltaganderättigheter i Ryssland.

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Kartta kuuluu A. E. Nordenskiöldin kokoelmaan

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L???Associaci?? Balear d???Alletament Matern (ABAM) conjuntament amb l???Institut per a l???Educaci?? de la Primera Inf??ncia i el Servei de Salut del Govern de les Illes Balears, han elaborat i facilitat aquestes orientacions per tal d???informar sobre l???alletament matern al llarg de l???estada dels infants a l???Escoleta.

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A multi-scale framework for decision support is presented that uses a combination of experiments, models, communication, education and decision support tools to arrive at a realistic strategy to minimise diffuse pollution. Effective partnerships between researchers and stakeholders play a key part in successful implementation of this strategy. The Decision Support Matrix (DSM) is introduced as a set of visualisations that can be used at all scales, both to inform decision making and as a communication tool in stakeholder workshops. A demonstration farm is presented and one of its fields is taken as a case study. Hydrological and nutrient flow path models are used for event based simulation (TOPCAT), catchment scale modelling (INCA) and field scale flow visualisation (TopManage). One of the DSMs; The Phosphorus Export Risk Matrix (PERM) is discussed in detail. The PERM was developed iteratively as a point of discussion in stakeholder workshops, as a decision support and education tool. The resulting interactive PERM contains a set of questions and proposed remediation measures that reflect both expert and local knowledge. Education and visualisation tools such as GIS, risk indicators, TopManage and the PERM are found to be invaluable in communicating improved farming practice to stakeholders. (C) 2008 Elsevier Ltd. All rights reserved.

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A generic Nutrient Export Risk Matrix (NERM) approach is presented. This provides advice to farmers and policy makers on good practice for reducing nutrient loss and is intended to persuade them to implement such measures. Combined with a range of nutrient transport modelling tools and field experiments, NERMs can play an important role in reducing nutrient export from agricultural land. The Phosphorus Export Risk Matrix (PERM) is presented as an example NERM. The PERM integrates hydrological understanding of runoff with a number of agronomic and policy factors into a clear problem-solving framework. This allows farmers and policy makers to visualise strategies for reducing phosphorus loss through proactive land management. The risk Of Pollution is assessed by a series of informed questions relating to farming intensity and practice. This information is combined with the concept of runoff management to point towards simple, practical remedial strategies which do not compromise farmers' ability to obtain sound economic returns from their crop and livestock.

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A análise da condição feminina é polêmica, sobremaneira, quando a trilha a ser seguida se lnsere no veio organizacional,c~ minho ainda virgem na literatura corrente. o que se tenta em termos amplos é indagar,até que ponto, as organizações negligenciam, ou ainda, reforçam,no interior de las a situação de inferioridade da mulher no plano social e familiar, seja através da cultura organizacional,com valores tradici~ nalmente "patriarcais",ou através de normas, procedimentos e ou tros instrumentos de controle da conduta funcional. o foco do estudo recairá numa Autarquia Federal (AF) , possuidora de especificidades próprias que~asseguram por um la do, no que concerne às políticas de pessoal,o ingresso e a perm~ nência de mulheres e, por outro, a reprodução das condições malS gerais de opressao de sexo ,d e uma sociedade tradicional como a brasileira. o que se tenta especificamente conhecer, é como as fun cionárias e funcionários da AF se inserem no processo de ascen são funcional, doravante chamado de o caminho para o "sucesso";se há diferenças substanciais na maneira de perceber o trabalho em si e na sua intercessão com outras esferas da vida, como família, lazer, cultura, saúde e consumo, ou na maneira de perceber o "sucesso", os requisitos e as disponibilidades para se chegar até ele. Procurar-se-á,então, levantar os possíveis pontos de estrangulamento da carreira da mulher na organização. Acredita-se que, nao obstante os condicionantes supeE. estruturais e micro-institucionais que obstaculizam a ascensao funcional feminina, sua postura em relação ao trabalho e ao "sucesso" encontrará eco em fatores outros,advindos precipuamente de sua posição na hierarquia, por hipótese.

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O Mesozóico foi marcado por mudanças geológicas significativas, decorrentes de soerguimentos resultante da orogenia Gonduanide, que possibilitou a implantação de sistemas desérticos concomitantemente com expressivos eventos magmáticos. Na Bacia do Parnaíba, Nordeste do Brasil, estes eventos estão registrados nas unidades siliciclásticas do Triássico, os arenitos da Formação Sambaíba, representadas pelos derrames basálticos e arenitos fluviais e eólicos subordinados da Formação Mosquito e pelos arenitos flúvio-eólicos da Formação Corda. O estudo de fácies e estratigráfico realizado em afloramentos e testemunhos de sondagem na região entre Formosa da Serra Negra e Montes Altos, Estado do Maranhão, possibilitou reconstituir o paleoambiente do topo da Formação Mosquito e da Formação Corda, e inferir condições paleoclimáticas para a porção centro-oeste da Bacia do Parnaíba durante o Jurássico. Foram identificadas vinte fácies sedimentares agrupadas em cinco associações de fácies (AF) representativas de uma planície vulcânica com depósitos fluviais esporádicos e arenitos eólicos subordinados (AF1-Formação Mosquito), sucedida pela instalação de um sistema desértico úmido (AF2-AF5; Formação Corda). A planície vulcânica (AF1) constitui derrames basálticos intercalados com arenitos finos a grossos (arenitos intertrap) compostos por grãos arredondados a subangulosos de quartzo, feldspatos e fragmentos de vidro vulcânico. Os arenitos apresentam estratificações plano-paralela e cruzada de baixo ângulo, preenchendo geometria de canal ou em corpos tabulares. Depósitos de canal fluvial entrelaçado (AF2) consistem em conglomerados polimíticos, com grânulos e seixos subarredondados a angulosos de basalto, e arenitos grossos com estratificação cruzada acanalada e acamamento maciço. Os lençóis arenosos (AF3) foram divididos em dois elementos arquiteturais (EA), o primeiro (EA1) consistem em arenitos finos a muitos com geometria tabular e estruturas de deformação, o segundo (EA2) é composto por arenito fino a grosso com estratificação cruzada acanalada e laminação cruzada cavalgante, gutter cast de pequeno porte. O campo de dunas (AF4) foi subdividido em dois conjuntos de fácies (C), o primeiro (CI) é caracterizado por arenitos com estratificações cruzadas tabular e tangencial de pequeno a médio porte, estratificação planoparalela e laminação cruzada cavalgante transladante subcrítica. O segundo (CII) consiste de arenitos finos a médios, moderadamente selecionados, laminação ondulada e estruturas de adesão e gretas de contração com rip-up clast, curled mud flakes, forma ciclos de raseamento centimétricos, com topo marcado por horizontes mosqueados, ricos em óxido/hidróxido de ferro, bioturbações e gretas de contração, interpretados como depósitos de interdunas úmidas. Os lobos de suspensão (AF5) consistem em arenitos finos intercalados com pelitos e arenito/pelito com estratificação cruzada complexa. A abundância de esmectita na AF4 aponta para condições de clima semiárido. No Jurássico, a região centro-oeste da Bacia do Parnaíba, foi submetida a movimentos distensivos com recorrência de derrames básicos advindos de fissuras na crosta. Durante os intervalos de aquiescência sedimentos de rios efêmeros preenchiam depressões ou espraiavam-se na planície vulcânica. O final da atividade magmática foi sucedido pela implantação do desérto Corda com campo de dunas e canais fluviais efêmeros (wadi) que retrabalharam parte da planície vulcânica e esporadicamente invadiam os lençóis arenosos. Comparado aos ergs do Permo-Triássico (Formação Sambaíba), o deserto Jurássico da Formação Corda foi mais úmido e menos extenso precedendo os sistemas fluviais e costeiros de clima mais ameno do Cretáceo da Bacia do Parnaíba.

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The aim of this study was to evaluate the effect of 2% chlorhexidine digluconate (CHX) on immediate bond strength of etch-and-rinse adhesive to sound (SD) and caries-affected (CAD) primary dentin compared with permanent dentin. Flat dentin surfaces from 20 primary molars (Pri) and 20 permanent molars (Perm) were assigned to 8 experimental groups (n=5) according to tooth type (Pri or Perm), dentin condition (SD or CAD - pH-cycling for 14 days) and treatment (control - C or 60 s application of 2% CHX solution after acid etching - CHX). The bonding system (Adper Single Bond 2) was applied according to manufacturer's instructions followed by resin composite application (Filtek Z250). After 24 h water storage, specimens with cross-section area of 0.8 mm² were prepared for being tested under microtensile test (1 mm/min). Data were submitted to ANOVA and Tukey's post hoc test (α=0.05). Failure mode was evaluated using a stereomicroscope at ×400. Treatment with CHX did not result in higher bond strength values than no pre-treatment (C groups), independently of tooth type. Primary teeth and caries-affected dentin showed significantly lower (p<0.05) bond strength means compared with permanent teeth and sound dentin, respectively. Predominance of adhesive/mixed failure was observed for all groups. CHX did not influence the immediate bond strength to sound or caries-affected dentin of primary and permanent teeth.

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The work of this thesis has been focused on the characterization of metallic membranes for the hydrogen purification from steam reforming process and also of perfluorosulphonic acid ionomeric (PFSI) membranes suitable as electrolytes in fuel cell applications. The experimental study of metallic membranes was divided in three sections: synthesis of palladium and silver palladium coatings on porous ceramic support via electroless deposition (ELD), solubility and diffusivity analysis of hydrogen in palladium based alloys (temperature range between 200 and 400 °C up to 12 bar of pressure) and permeation experiments of pure hydrogen and mixtures containing, besides hydrogen, also nitrogen and methane at high temperatures (up to 600 °C) and pressures (up to 10 bar). Sequential deposition of palladium and silver on to porous alumina tubes by ELD technique was carried out using two different procedures: a stirred batch and a continuous flux method. Pure palladium as well as Pd-Ag membranes were produced: the Pd-Ag membranes’ composition is calculated to be close to 77% Pd and 23% Ag by weight which was the target value that correspond to the best performance of the palladium-based alloys. One of the membranes produced showed an infinite selectivity through hydrogen and relatively high permeability value and is suitable for the potential use as a hydrogen separator. The hydrogen sorption in silver palladium alloys was carried out in a gravimetric system on films produced by ELD technique. In the temperature range inspected, up to 400°C, there is still a lack in literature. The experimental data were analyzed with rigorous equations allowing to calculate the enthalpy and entropy values of the Sieverts’ constant; the results were in very good agreement with the extrapolation made with literature data obtained a lower temperature (up to 150 °C). The information obtained in this study would be directly usable in the modeling of hydrogen permeation in Pd-based systems. Pure and mixed gas permeation tests were performed on Pd-based hydrogen selective membranes at operative conditions close to steam-reforming ones. Two membranes (one produced in this work and another produced by NGK Insulators Japan) showed a virtually infinite selectivity and good permeability. Mixture data revealed the existence of non negligible resistances to hydrogen transport in the gas phase. Even if the decrease of the driving force due to polarization concentration phenomena occurs, in principle, in all membrane-based separation systems endowed with high perm-selectivity, an extensive experimental analysis lack, at the moment, in the palladium-based membrane process in literature. Moreover a new procedure has been introduced for the proper comparison of the mass transport resistance in the gas phase and in the membrane. Another object of study was the water vapor sorption and permeation in PFSI membranes with short and long side chains was also studied; moreover the permeation of gases (i.e. He, N2 and O2) in dry and humid conditions was considered. The water vapor sorption showed strong interactions between the hydrophilic groups and the water as revealed from the hysteresis in the sorption-desorption isotherms and thermo gravimetric analysis. The data obtained were used in the modeling of water vapor permeation, that was described as diffusion-reaction of water molecules, and in the humid gases permeation experiments. In the dry gas experiments the permeability and diffusivity was found to increase with temperature and with the equivalent weight (EW) of the membrane. A linear correlation was drawn between the dry gas permeability and the opposite of the equivalent weight of PFSI membranes, based on which the permeability of pure PTFE is retrieved in the limit of high EW. In the other hand O2 ,N2 and He permeability values was found to increase significantly, and in a similar fashion, with water activity. A model that considers the PFSI membrane as a composite matrix with a hydrophilic and a hydrophobic phase was considered allowing to estimate the variation of gas permeability with relative humidity on the basis of the permeability in the dry PFSI membrane and in pure liquid water.

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Membrane-based separation processes are acquiring, in the last years, an increasing importance because of their intrinsic energetic and environmental sustainability: some types of polymeric materials, showing adequate perm-selectivity features, appear rather suitable for these applications, because of their relatively low cost and easy processability. In this work have been studied two different types of polymeric membranes, in view of possible applications to the gas separation processes, i.e. Mixed Matrix Membranes (MMMs) and high free volume glassy polymers. Since the early 90’s, it has been understood that the performances of polymeric materials in the field of gas separations show an upper bound in terms of permeability and selectivity: in particular, an increase of permeability is often accompanied by a decrease of selectivity and vice-versa, while several inorganic materials, like zeolites or silica derivates, can overcome this limitation. As a consequence, it has been developed the idea of dispersing inorganic particles in polymeric matrices, in order to obtain membranes with improved perm-selectivity features. In particular, dispersing fumed silica nanoparticles in high free volume glassy polymers improves in all the cases gases and vapours permeability, while the selectivity may either increase or decrease, depending upon material and gas mixture: that effect is due to the capacity of nanoparticles to disrupt the local chain packing, increasing the dimensions of excess free volume elements trapped in the polymer matrix. In this work different kinds of MMMs were fabricated using amorphous Teflon® AF or PTMSP and fumed silica: in all the cases, a considerable increase of solubility, diffusivity and permeability of gases and vapours (n-alkanes, CO2, methanol) was observed, while the selectivity shows a non-monotonous trend with filler fraction. Moreover, the classical models for composites are not able to capture the increase of transport properties due to the silica addition, so it has been necessary to develop and validate an appropriate thermodynamic model that allows to predict correctly the mass transport features of MMMs. In this work, another material, called poly-trimethylsilyl-norbornene (PTMSN) was examined: it is a new generation high free volume glassy polymer that, like PTMSP, shows unusual high permeability and selectivity levels to the more condensable vapours. These two polymer differ each other because PTMSN shows a more pronounced chemical stability, due to its structure double-bond free. For this polymer, a set of Lattice Fluid parameters was estimated, making possible a comparison between experimental and theoretical solubility isotherms for hydrocarbons and alcoholic vapours: the successfully modelling task, based on application of NELF model, offers a reliable alternative to direct sorption measurement, which is extremely time-consuming due to the relevant relaxation phenomena showed by each sorption step. For this material also dilation experiments were performed, in order to quantify its dimensional stability in presence of large size, swelling vapours.