Vers��o resumida da "job stress scale": adapta����o para o portugu��s

OBJETIVO: Descrever o processo de adapta����o, para o portugu��s, da vers��o resumida da "job stress scale", originalmente elaborada em ingl��s. M��TODOS: Foram avaliados seis aspectos de equival��ncia entre a escala original e a vers��o para o portugu��s: as equival��ncias conceitual, sem��ntica, operacional, de itens, de medidas e funcional. Tomou-se por base um estudo de confiabilidade teste-reteste com 94 indiv��duos selecionados. RESULTADOS: O estudo de confiabilidade teste-reteste entre 94 indiv��duos permitiu estimativas de reprodutibilidade (coeficientes de correla����o intraclasse) para as dimens��es de "demanda", "controle" e "apoio social" da escala de 0,88, 0,87 e 0,85, respectivamente. Para as mesmas dimens��es, as estimativas de consist��ncia interna (alpha de Cronbach) foram, respectivamente, 0,79, 0,67 e 0,85. CONCLUS��ES: Os resultados sugerem que o processo de adapta����o da escala foi bem sucedido, indicando que seu uso no contexto sociocultural da popula����o de estudo (Estudo Pr��-Sa��de) �� apropriado.

Wind turbines equipped with fractional-order controllers: Stress on the mechanical drive train due to a converter control malfunction

This paper is on variable-speed wind turbines with permanent magnet synchronous generator (PMSG). Three different drive train mass models and three different topologies for the power-electronic converters are considered. The three different topologies considered are respectively a matrix, a two-level and a multilevel converter. A novel control strategy, based on fractional-order controllers, is proposed for the wind turbines. Simulation results are presented to illustrate the behaviour of the wind turbines during a converter control malfunction, considering the fractional-order controllers. Finally, conclusions are duly drawn. Copyright (C) 2010 John Wiley & Sons, Ltd.

Ensino e aprendizagem da Bioqu��mica em Ci��ncias da Sa��de: reten����o de conhecimentos adquiridos e sucesso acad��mico versus tipo de exame preferido, sua prepara����o e stress associado

Num contexto de reestrutura����o da forma����o em Ci��ncias da Sa��de baseada em compet��ncias, torna-se necess��rio estudar as diferentes formas de avalia����o e o stress que lhe est�� associado, observando de que forma estas poder��o interferir no sucesso acad��mico dos alunos e real aquisi����o de compet��ncias. O objectivo do trabalho foi avaliar estas quest��es no ��mbito da Bioqu��mica de diferentes cursos de Tecnologias da Sa��de. A metodologia foi adaptada de controlled pre-test-postest, e os resultados obtidos apontam para que os alunos que mais estudam, ao longo do ano e n��o no ���sprint final���, parecem possuir menor stress e serem melhor sucedidos.

Le moment venu ou l���eveil d��s editoriaux. Mutations de la litt��rature des ann��es quatre-vingt vues par les revues litt��raires

Les ann��es quatre-vingt signalent un point de bascule dans et une mutation majeure dans les caract��ristiques narratives de la litt��rature fran��aise. D���une certaine fa��on, elles entament la contemporan��it�� litt��raire telle que nous la connaissons du point de vue critique. Nous insisterons sur le r��le des revues et des ��ditoriaux dans ce processus. Ils manifestent quelques h��sitations de la critique par rapport �� la litt��rature naissante.

(Des)encontros trabalho-fam��lia: narrativas de familiares de trabalhadores migrantes do setor de produ����o de energia hidrel��trica

P��s-gradua����o em Psicologia - FCLAS

Pratiques d���enseignement en lecture-��criture et apprentissages des ��l��ves au d��but du primaire

Esta investiga����o pretende contribuir para o desenvolvimento da investiga����o interessada nas quest��es relativas ao ensino/ aprendizagem do modo escrito nos primeiros anos do primeiro ciclo do ensino b��sico, particularmente tendo em conta as pr��ticas mais propensas a apoiar a aprendizagem bem-sucedida da leitura e de escrita. Especificamente, esta investiga����o tem como objetivo descrever as pr��ticas de ensino observadas nas ��reas da leitura e da escrita com 22 professores, mas tamb��m para relacionar essas pr��ticas observadas com o desempenho em leitura e escrita dos seus alunos do primeiro e do segundo ano. Globalmente, os resultados indicam que as pr��ticas observadas, tanto do ponto de vista dos Dispositivos mobilizados como do conte��do ensinado, s��o variadas e contribuem para uma vis��o complexa da entrada na escrita. As an��lises de correla����o sugerem que determinadas pr��ticas, que geralmente procuram a participa����o activa das crian��as e as intera����es com os outros, est��o relacionados com o progresso dos alunos durante o ano letivo.

Effect of oxidative stress upon absorption of glucose by the human placenta: in vitro studies with BeWo cells

Pregnancy is a dynamic state and the placenta is a temporary organ that, among other important functions, plays a crucial role in the transport of nutrients and metabolites between the mother and the fetus, which is essential for a successful pregnancy. Among these nutrients, glucose is considered a primary source of energy and, therefore, fundamental to insure proper fetus development. Several studies have shown that glucose uptake is dependent on several morphological and biochemical placental conditions. Oxidative stress results from the unbalance between reactive oxygen species (ROS) and antioxidants, in favor of the first. During pregnancy, ROS, and therefore oxidative stress, increase, due to increased tissue oxygenation. Moreover, the relation between ROS and some pathological conditions during pregnancy has been well established. For these reasons, it becomes essential to understand if oxidative stress can compromise the uptake of glucose by the placenta. To make this study possible, a trophoblastic cell line, the BeWo cell line, was used. Experiments regarding glucose uptake, either under normal or oxidative stress conditions, were conducted using tert-butylhydroperoxide (tBOOH) as an oxidative stress inducer, and 3H-2-deoxy-D-glucose (3H-DG) as a glucose analogue. Afterwards, studies regarding the involvement of glucose facilitative transporters (GLUT) and the phosphatidylinositol 3-kinases (PI3K) and protein kinase C (PKC) pathways were conducted, also under normal and oxidative stress conditions. A few antioxidants, endogenous and from diet, were also tested in order to study their possible reversible effect of the oxidative effect of tBOOH upon apical 3H-DG uptake. Finally, transepithelial studies gave interesting insights regarding the apical-to-basolateral transport of 3H-DG. Results showed that 3H-DG uptake, in BeWo cells, is roughly 50% GLUT-mediated and that tBOOH (100 ��M; 24h) decreases apical 3H-DG uptake in BeWo cells by about 33%, by reducing both GLUT- (by 28%) and non-GLUT-mediated (by 40%) 3H-DG uptake. Uptake of 3H-DG and the effect of tBOOH upon 3H-DG uptake are not dependent on PKC and PI3K. Moreover, the effect of tBOOH is not associated with a reduction in GLUT1 mRNA levels. Resveratrol, quercetin and epigallocatechin-3-gallate, at 50 ��M, reversed, by at least 45%, the effect of tBOOH upon 3H-DG uptake. Transwell studies show that the apical-to-basolateral transepithelial transport of 3H-DG is increased by tBOOH.In conclusion, our results show that tBOOH caused a marked decrease in both GLUT and non-GLUT-mediated apical uptake of 3H-DG by BeWo cells. Given the association of increased oxidative stress levels with several important pregnancy pathologies, and the important role of glucose for fetal development, the results of this study appear very interesting.

Redes (des)conexas de interven����o local na viol��ncia infanto-juvenil

O objectivo deste estudo �� apresentar os resultados de uma an��lise diagn��stica da atua����o institucional relativamente ��s situa����es de viol��ncia infanto-juvenil em tr��s territ��rios de um concelho da per��feria de Lisboa(Portugal)

Metal accumulation and oxidative stress biomarkers in octopus (Octopus vulgaris) from Northwest Atlantic

Metals are ubiquitous in the environment and accumulate in aquatic organisms and are known for their ability to enhance the production of reactive oxygen species (ROS). In aquatic species, oxidative stress mechanisms have been studied by measuring antioxidant enzyme activities and oxidative damages in tissues. The aim of this study was to apply and validate a set of oxidative stress biomarkers and correlate responses with metal contents in tissues of common octopus (Octopus vulgaris). Antioxidant enzyme activity (catalase ��� CAT, superoxide dismutase ��� SOD and glutathione S-transferases ��� GST), oxidative damages (lipid peroxidation ��� LPO and protein carbonyl content ��� PCO) andmetal content (Cu, Zn, Pb, Cd and As) in the digestive gland and armof octopus, collected in the NWPortuguese coast in different periods, were assessed after capture and after 14 days in captivity. CAT and SOD activitieswere highly responsive to fluctuations inmetal concentrations and able to reduce oxidative damage, LPO and PCO in the digestive gland. CAT activity was also positively correlated with SOD and GST activities, which emphasizes that the three enzymes respond in a coordinated way to metal induced oxidative stress. Our results validate the use of oxidative stress biomarkers to assess metal pollution effects in this ecological and commercial relevant species.Moreover, octopus seems to have the ability to control oxidative damage by triggering an antioxidant enzyme coordinated response in the digestive gland.

OsRMC, a negative regulator of salt stress response in rice, is regulated by two AP2/ERF transcription factors

High salinity causes remarkable losses in rice productivity worldwide mainly because it inhibits growth and reduces grain yield. To cope with environmental changes, plants evolved several adaptive mechanisms, which involve the regulation of many stress-responsive genes. Among these, we have chosen OsRMC to study its transcriptional regulation in rice seedlings subjected to high salinity. Its transcription was highly induced by salt treatment and showed a stress-dose-dependent pattern. OsRMC encodes a receptor-like kinase described as a negative regulator of salt stress responses in rice. To investigate how OsRMC is regulated in response to high salinity, a salt-induced rice cDNA expression library was constructed and subsequently screened using the yeast one-hybrid system and the OsRMC promoter as bait. Thereby, two transcription factors (TFs), OsEREBP1 and OsEREBP2, belonging to the AP2/ERF family were identified. Both TFs were shown to bind to the same GCC-like DNA motif in OsRMC promoter and to negatively regulate its gene expression. The identified TFs were characterized regarding their gene expression under different abiotic stress conditions. This study revealed that OsEREBP1 transcript level is not significantly affected by salt, ABA or severe cold (5 ��C) and is only slightly regulated by drought and moderate cold. On the other hand, the OsEREBP2 transcript level increased after cold, ABA, drought and high salinity treatments, indicating that OsEREBP2 may play a central role mediating the response to different abiotic stresses. Gene expression analysis in rice varieties with contrasting salt tolerance further suggests that OsEREBP2 is involved in salt stress response in rice.

Protection against oxidative stress through SUA7/TFIIB regulation in Saccharomyces cerevisiae

The general transcription factor TFIIB, encoded by SUA7 in Saccharomyces cerevisiae, is required for transcription activation but apparently of a specific subset of genes, for example, linked with mitochondrial activity and hence with oxidative environments. Therefore, studying SUA7/TFIIB as a potential target of oxidative stress is fundamental. We found that controlled SUA7 expression under oxidative conditions occurs at transcriptional and mRNA stability levels. Both regulatory events are associated with the transcription activator Yap1 in distinct ways: Yap1 affects SUA7 transcription up regulation in exponentially growing cells facing oxidative signals; the absence of this activator per se contributes to increase SUA7 mRNA stability. However, unlike SUA7 mRNA, TFIIB abundance is not altered on oxidative signals. The biological impact of this preferential regulation of SUA7 mRNA pool is revealed by the partial suppression of cellular oxidative sensitivity by SUA7 overexpression, and supported by the insights on the existence of a novel RNA-binding factor, acting as an oxidative sensor, which regulates mRNA stability. Taken together the results point out a primarily cellular commitment to guarantee SUA7 mRNA levels under oxidative environments.

Expression of YAP4 in Saccharomyces cerevisiae under osmotic stress

YAP4, a member of the yeast activator protein (YAP) gene family, is induced in response to osmotic shock in the yeast Saccharomyces cerevisiae. The null mutant displays mild and moderate growth sensitivity at 0.4 M and 0.8 M NaCl respectively, a fact that led us to analyse YAP4 mRNA levels in the hog1 (high osmolarity glycerol) mutant. The data obtained show a complete abolition of YAP4 gene expression in this mutant, placing YAP4 under the HOG response pathway. YAP4 overexpression not only suppresses the osmosensitivity phenotype of the yap4 mutant but also relieves that of the hog1 mutant. Induction, under the conditions tested so far, requires the presence of the transcription factor Msn2p, but not of Msn4p, as YAP4 mRNA levels are depleted by at least 75% in the msn2 mutant. This result was further substantiated by the fact that full YAP4 induction requires the two more proximal stress response elements. Furthermore we find that GCY1, encoding a putative glycerol dehydrogenase, GPP2, encoding a NAD-dependent glycerol-3-phosphate phosphatase, and DCS2, a homologue to a decapping enzyme, have decreased mRNA levels in the yap4 -deleted strain. Our data point to a possible, as yet not entirely understood, role of the YAP4 in osmotic stress response.

Uma (des)complicada viagem ao mundo dos paradoxos

[...]. Na matem��tica e na filosofia h�� muitos exemplos. Obviamente n��o faremos a separa����o entre os paradoxos na matem��tica e na filosofia, pois os maiores fil��sofos desta ��rea eram tamb��m os maiores matem��ticos do seu tempo. Sem qualquer inten����o de ferir a sensibilidade religiosa do leitor, apresento o famoso paradoxo de Nietzche (1844-1900) da Omnipot��ncia de Deus. [...].

Crescimento de Ulva rigida C. Agardh em condi����es de stress de macronutrientes

Disserta����o de Mestrado em Biodiversidade e Biotecnologia Vegetal