348 resultados para 1322


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A cyanobacterial mat colonizing the leaves of Eucalyptus grandis was determined to be responsible for serious damage affecting the growth and development of whole plants under the clonal hybrid nursery conditions. The dominant cyanobacterial species was isolated in BG-11 medium lacking a source of combined nitrogen and identified by cell morphology characters and molecular phylogenetic analysis (16S rRNA gene and cpcBA-IGS sequences). The isolated strain represents a novel species of the genus Brasilonema and is designated Brasilonema octagenarum strain UFV-E1. Thin sections of E. grandis leaves analyzed by light and electron microscopy showed that the B. octagenarum UFV-E1 filaments penetrate into the leaf mesophyll. The depth of infection and the mechanism by which the cyanobacterium invades leaf tissue were not determined. A major consequence of colonization by this cyanobacterium is a reduction in photosynthesis in the host since the cyanobacterial mats decrease the amount of light incident on leaf surfaces. Moreover, the cyanobacteria also interfere with stomatal gas exchange, decreasing CO2 assimilation. To our knowledge, this is the first report of an epiphytic cyanobacterial species causing damage to E. grandis leaves.

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Families with a child on chronic peritoneal dialysis have to assume a significant burden of care, intensifying the demands and the reorganization of roles in the families of children. The purpose of this study is to describe the implications of role changes in families of children with chronic renal disease on peritoneal dialysis. This is a case study of four families of children with chronic renal disease on peritoneal dialysis. Fourteen family members participate in the study. After the child`s chronic kidney failure and the start of treatment, each relative`s ways, acts and functions are changed, maintained or adapted to the new family dynamics, imposed by the child`s treatment conditions. Appropriate role assessment provides the nurse and the families of children with chronic renal failure on peritoneal dialysis with insight regarding current and potential health problems and aids in identifying the needs of the families.

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This paper presents a study of families of children with type 1 diabetes mellitus, emphasizing the identification of social supports and networks to strengthen interventions aimed at health promotion. The approach selected was a qualitative research, using a case study design. Four families of children with diabetes type 1 were studied, totalling seven participants. Data were collected between April and June 2007, through in-depth interviews and the construction of a genogram and an ecomap. The results presented the families` characterization and testimonies grouped in the following categories: social support, social networks and family roles. To promote care in practice, there is a need to identify the characteristics of each family and resources available that provide better living conditions. We concluded that identifying supports and social networks allows for more personalized care delivery to each family with a view to health promotion.

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This letter presents the properties of nMOS junctionless nanowire transistors (JNTs) under cryogenic operation. Experimental results of drain current, subthreshold slope, maximum transconductance at low electric field, and threshold voltage, as well as its variation with temperature, are presented. Unlike in classical devices, the drain current of JNTs decreases when temperature is lowered, although the maximum transconductance increases when the temperature is lowered down to 125 K. An analytical model for the threshold voltage is proposed to explain the influence of nanowire width and doping concentration on its variation with temperature. It is shown that the wider the nanowire or the lower the doping concentration, the higher the threshold voltage variation with temperature.

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This study aimed to evaluate adult emergence and duration of the pupal stage of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), and emergence of the fruit fly parasitoid, Diachasmimorpha longicaudata (Ashmead), under different moisture conditions in four soil types, using soil water matric potential Pupal stage duration in C capitata was influenced differently for males and females In females, only soil type affected pupal stage duration, which was longer in a clay soil In males, pupal stage duration was individually influenced by moisture and soil type, with a reduction in pupal stage duration in a heavy clay soil and in a sandy clay, with longer duration in the clay soil As allude potential decreased, duration of the pupal stage of C capitata males increased, regardless of soil type C capitata emergence was affected by moisture, regardless of soil type, and was higher in drier soils The emergence of D longicaudata adults was individually influenced by soil type and moisture factors, and the number of emerged D longicaudata adults was three times higher in sandy loam and lower in a heavy clay soil Always, the number of emerged adults was higher at higher moisture conditions C capitata and D longicaudata pupal development was affected by moisture and soil type, which may facilitate pest sampling and allow release areas for the parasitoid to be defined under field conditions.

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Here, we examine morphological changes in cortical thickness of patients with Alzheimer`s disease (AD) using image analysis algorithms for brain structure segmentation and study automatic classification of AD patients using cortical and volumetric data. Cortical thickness of AD patients (n = 14) was measured using MRI cortical surface-based analysis and compared with healthy subjects (n = 20). Data was analyzed using an automated algorithm for tissue segmentation and classification. A Support Vector Machine (SVM) was applied over the volumetric measurements of subcortical and cortical structures to separate AD patients from controls. The group analysis showed cortical thickness reduction in the superior temporal lobe, parahippocampal gyrus, and enthorhinal cortex in both hemispheres. We also found cortical thinning in the isthmus of cingulate gyrus and middle temporal gyrus at the right hemisphere, as well as a reduction of the cortical mantle in areas previously shown to be associated with AD. We also confirmed that automatic classification algorithms (SVM) could be helpful to distinguish AD patients from healthy controls. Moreover, the same areas implicated in the pathogenesis of AD were the main parameters driving the classification algorithm. While the patient sample used in this study was relatively small, we expect that using a database of regional volumes derived from MRI scans of a large number of subjects will increase the SVM power of AD patient identification.

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Background: This study of a chronic porcine postinfarction model examined whether linear epicardial cryoablation was capable of creating large, homogenous lesions in regions of the myocardium including scarred ventricle. Endocardial and epicardial focal cryolesions were also compared to determine if there were significant differences in lesion characteristics. Methods: Eighty focal endocardial and 28 focal epicardial cryoapplications were delivered to eight normal caprine and four normal porcine ventricular myocardium, and 21 linear cryolesions were applied along the border of infarcted epicardial tissue in a chronic porcine infarct model in six swines. Results: Focal endocardial cryolesions in normal animals measured 9.7 +/- 0.4 mm (length) by 7.3 +/- 1.4 mm (width) by 4.8 +/- 0.2 mm (depth), while epicardial lesions measured 10.2 +/- 1.4 mm (length) by 7.7 +/- 2 mm (width) by 4.6 +/- 0.9 mm (depth); P > 0.05. Linear epicardial cryolesions in the chronic porcine infarct model measured 36.5 +/- 7.8 mm (length) by 8.2 +/- 1.3 mm (width) by 6.0 +/- 1.2 mm (depth). The mean depth of linear cryolesions applied to the border of the infarct scar was 7 +/- 0.7 mm, as measured by magnetic resonance imaging. Conclusions:Cryoablation can create deep lesions when delivered to the ventricular epicardium. Endocardial and epicardial cryolesions created by a focal cryoablation catheter are similar in size and depth. The ability to rapidly create deep linear cryolesions may prove to be beneficial in substrate-based catheter ablation of ventricular arrhythmias.

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Two putative promoters from Australian banana streak badnavirus (BSV) isolates were analysed for activity in different plant species. In transient expression systems the My (2105 bp) and Cv (1322 bp) fragments were both shown to have promoter activity in a wide range of plant species including monocots (maize, barley, banana, millet, wheat, sorghum), dicots (tobacco, canola, sunflower, Nicotiana benthamiana, tipu tree), gymnosperm (Pinus radiata) and fern (Nephrolepis cordifolia). Evaluation of the My and Cv promoters in transgenic sugarcane, banana and tobacco plants demonstrated that these promoters could drive high-level expression of either the green fluorescent protein (GFP) or the beta -glucuronidase (GUS) reporter gene (uidA) in vegetative plant cells. In transgenic sugarcane plants harbouring the Cv promoter, GFP expression levels were comparable or higher (up to 1.06% of total soluble leaf protein as GFP) than those of plants containing the maize ubiquitin promoter (up to 0.34% of total soluble leaf protein). GUS activities in transgenic in vitro-grown banana plants containing the My promoter were up to seven-fold stronger in leaf tissue and up to four-fold stronger in root and corm tissue than in plants harbouring the maize ubiquitin promoter. The Cv promoter showed activities that were similar to the maize ubiquitin promoter in in vitro-grown banana plants, but was significantly reduced in larger glasshouse-grown plants. In transgenic in vitro-grown tobacco plants, the My promoter reached activities close to those of the 35S promoter of cauliflower mosaic virus (CaMV), while the Cv promoter was about half as active as the CaMV 35S promoter. The BSV promoters for pregenomic RNA represent useful tools for the high-level expression of foreign genes in transgenic monocots.

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Este artigo analisa as altera????es ao regime jur??dico dos dirigentes da fun????o p??blica portuguesa, que constam da proposta apresentada pelo Governo. Mencionam-se, ainda, as limita????es verificadas e os princ??pios orientadores da reforma. Em seguida, analisam-se de um ponto de vista cr??tico alguns aspectos, designadamente, a miss??o do dirigente, as categorias e os n??veis, as compet??ncias, a forma????o, o recrutamento e a selec????o, o provimento, a dura????o das comiss??es de servi??o e a sua renova????o. Por fim, aponta-se a import??ncia de monitorar a aplica????o da lei, tendo em vista verificar o seu papel na mudan??a.

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O presente trabalho teve como objetivo principal investigar concepções que estudantes do terceiro ano do ensino médio possuem sobre direitos e obrigações essenciais ao exercício da cidadania. Para tanto, foi elaborado um questionário composto de 20 questões fechadas e 9 questões abertas na forma de estudo de caso abordando alguns direitos e obrigações essenciais ao exercício pleno da vida civil. O instrumento foi submetido a 136 estudantes, entre 16 e 18 anos, de ambos os sexos, regularmente matriculados no terceiro ano de três escolas públicas de Ensino Médio. Os resultados apontam que, de modo geral, as concepções dos estudantes sobre legislação estão mais próximas das disposições legislativas naqueles direitos que permeiam sua realidade prática e, vai se distanciando à medida que os direitos propostos estavam distantes de sua realidade, de modo que, aparentemente, o conhecimento que os mesmos possuem acerca dos direitos repousam mais no senso comum que no aprendizado escolar. As conclusões apontam a necessidade de estratégias pedagógicas para inserção de noções de Direito para os estudantes do Ensino Médio, principalmente transversalmente aos conteúdos concernentes às disciplinas da área das Ciências Humanas. Com base nessas conclusões, foi elaborada uma proposta com sugestões de diretrizes para implementação da Educação em Direito no contexto das disciplinas de História, Geografia, Sociologia e Filosofia, à partir de um entrelaçamento entre os conteúdos presentes no Currículo Básico da Escola Estadual do Espírito Santo e dispositivos legislativos que pudessem dialogar com as temáticas, em busca de estabelecer uma proposta mínima que pudesse, sem prejuízo do desenvolvimento dos conteúdos, servir como instrumento para promoção da Educação em Direito, contribuindo, assim, na formação para a Cidadania.

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RESUMO: Angola tem sido ao longo dos tempos objecto de cobiça por parte de países estrangeiros por motivações diversas, que foram desde interesses coloniais – como aconteceu com Portugal, que durante séculos a colonizou, e da Holanda, que dominou Luanda entre 1641 e 1648 – ou por interesses hegemónicos, ideológicos e políticos – como sucedeu com os EUA e a URSS, mas também com a Republica Popular da China e Cuba – e até por interesses regionais – como foram os casos da África do Sul e dos contíguos Congo Belga, hoje Republica Democrática do Congo, e Zâmbia. No entanto, a todos estes interesses diversos não se pode excluir um que lhes é transversal: o interesse económico. De facto, os 1246700 km² de que Angola dispõe, aliados à sua excelente localização geográfica com uma extensa costa atlântica e a sua extraordinária riqueza em recursos naturais podem explicar este envolvimento estrangeiro na História de Angola. No que diz respeito ao objecto da Dissertação, o envolvimento da ONU nas questões relacionadas com Angola remonta à década de 50, ou seja, ao período colonial e muito antes da independência do país em 1975, devido à política descolonizadora saída da II Guerra Mundial. Além disso, a dinâmica que emergiu da II Guerra Mundial, rapidamente, reconfigurou o panorama político internacional em dois blocos: o ocidental liderado pelos EUA e o de Leste liderado pela URSS, que se envolveram numa Guerra Fria, polarização cujos efeitos se ligam de forma trágica à guerra em Angola, primeiro para a autodeterminação, e, depois, já num contexto de independência, num conflito armado que ultrapassou o plano interno. Os interesses dos EUA e da URSS, que começaram por ser antagónicos, deram lugar em 1989 com o fim da bipolaridade a uma cooperação mais aberta e uma abertura política em Angola rumo à paz e ao início da construção da democracia. Neste trabalho estuda-se o papel da ONU em Angola, quer no período de luta pela independência, quer depois, na busca da paz no sangrento conflito – nem sempre civil – que mesmo antes da data da independência, a 11 de Novembro de 1975, e até Fevereiro de 2002, dilacerou o país. Procura-se, igualmente, analisar o contributo da ONU na consolidação das instituições e na construção de um regime democrático em Angola. ABSTRACT: Angola has been along time subject to the greed of several foreign countries for many reasons and motivations which go from colonial interests - that is the cases of, Portugal which for centuries colonized it, and Netherlands under whose administration had been Luanda between 1641 and 1648 - or for hegemonic, ideological and political interests - as it happened in regard to USA and USSR, but also People‟s Republic of China, Cuba, - and even for regional interests - regarding South Africa Republic, and the neighbouring countries, Democratic Republic of Congo (ancient Republic of the Congo “Leopoldville”), and the Republic of Zambia. On the other hand to these interests we may join another which is transversal to all of them: economic interest. Effectively, Angola‟s 481,351 square miles (1,246,700 Km2) estimated area, combined with its excellent geographical location with a lengthy Atlantic coast, its extraordinary richness in natural resources may well explain this foreign participation in its Political History. Concerning the objective of this work, the UN has been involved in matters regarding Angola since the decade of 50 of the last century, during the colonial period, long before the independence of the country in 1975, due to the decolonization policy emerged from the Second World War. Furthermore, after the Second World War, international environment has changed, transforming quickly the world into two main blocs, the West with the leadership of the USA and the East with the leadership of USSR which went into a Cold War. The effects of this polarization reached tragically Angola, early in the fight for self-determination, and went on later after independence in an armed conflict, which has overcome the internal dimension. The USA and USSR interests, at the beginning being antagonistic had become by 1989, with the end of bipolarity, more cooperative, leading Angola to a political reform towards peace and beginning the construction of democracy. In this academic work it‟s studied the UNO role in Angola since the fight for self-determination early in the sixties of last century, and later in the search for peace during the bloody - and not always civil – war conflict which very before independence date in 11th November 1975, and as long as 2002, divided the country. Additionally, this work aims to understand the UNO contribution to consolidate institutions and to promote democracy in Angola.

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Neste texto, apresenta-se uma das ideias mais desenvolvidas por Paul de Man, nomeadamente a de que a linguagem é fundamentalmente infeliz porque nela gramática e retórica se encontram em constante tensão. Assim, um mesmo enunciado afirma e nega simultaneamente e não há um contexto ideal que nos esclareça acerca do sentido.

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As wind power generation undergoes rapid growth, new technical challenges emerge: dynamic stability and power quality. The influence of wind speed disturbances and a pitch control malfunction on the quality of the energy injected into the electric grid is studied for variable-speed wind turbines with different power-electronic converter topologies. Additionally, a new control strategy is proposed for the variable-speed operation of wind turbines with permanent magnet synchronous generators. The performance of disturbance attenuation and system robustness is ascertained. Simulation results are presented and conclusions are duly drawn. (C) 2010 Elsevier Ltd. All rights reserved.

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Os Bombeiros estão expostos frequentemente a vários poluentes prejudicando gravemente a sua saúde respiratória. Foi realizado um estudo observacional e transversal, com o objectivo de caracterizar a função pulmonar dos bombeiros da região norte de Portugal. A amostra foi constituída por 44 Bombeiros de Valongo e Rebordosa. Todos os participantes preencheram um questionário, executaram espirometrias e mediram o monóxido de carbono. Verificou-se uma elevada prevalência de hábitos tabágicos, bem como da carga tabágica. A percentagem de alterações espirométricas foi de 38,6% e a utilização de protecção respiratória revelou-se praticamente inexistente nos incêndios florestais.

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Este artigo pretende fazer uma revisão de uma das últimas e inovadoras alternativas cirúrgicas viáveis para a cura da incontinência urinária de esforço feminina, com um sucesso superior a 86%. É uma cirurgia mini invasiva e que induz um suporte da uretra média livre de tensão, muito eficaz. Tem vantagens, poucas complicações, curto tempo operatório e benefícios para a doente no pós-operatório imediato e tardio.