Browsing by Issue Date, starting with "2014-09"
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- Translate into spanish of the conditions for work effectiveness questionnaire (CWEQ II)Publication . Mendoza Sierra, Maria Isabel; Orgambidez-Ramos, Alejandro; Borrego Ales, Yolanda; Gonçalves, Gabriela Maria Ramos; Santos, JoanaThe objective of this study is to adapt and translate into Spanish the Conditions for Work Effectiveness Questionnaire -CWEQ II-(Laschinger, Finegan, Shamian & Wilk, 2001). A process of translation and reverse-translation was applied to the scale's items, whose psychometric properties were then examined using a sample of 346 employees from a Spanish public university. Reliability, factor structure (confirmatory factor analysis) of the scale and relationships between structural, general and psychological empowerment are investigated. Results showed a multidimensional scale of four first-order factors (access to opportunities, information, support and resources) as the original one, and positive relations between structural, general and psychological empowerment in the workplace. Theoretical and practical implications of the findings are discussed and suggestions to further research are made.
- Polyhydroxyfullerene binds cadmium ions and alleviates metal-induced oxidative stress in saccharomyces cerevisiaePublication . Pradhan, Arunava; Pinheiro, José Paulo; Seena, Sahadevan; Pascoal, Claudia; Cassio, FernandaThe water-soluble polyhydroxyfullerene (PHF) is a functionalized carbon nanomaterial with several industrial and commercial applications. There have been controversial reports on the toxicity and/or antioxidant properties of fullerenes and their derivatives. Conversely, metals have been recognized as toxic mainly due to their ability to induce oxidative stress in living organisms. We investigated the interactive effects of PHF and cadmium ions (Cd) on the model yeast Saccharomyces cerevisiae by exposing cells to Cd (<= 5 mg liter(-1)) in the absence or presence of PHF (<= 500 mg liter(-1)) at different pHs (5.8 to 6.8). In the absence of Cd, PHF stimulated yeast growth up to 10.4%. Cd inhibited growth up to 79.7%, induced intracellular accumulation of reactive oxygen species (ROS), and promoted plasma membrane disruption in a dose- and pH-dependent manner. The negative effects of Cd on growth were attenuated by the presence of PHF, and maximum growth recovery (53.8%) was obtained at the highest PHF concentration and pH. The coexposure to Cd and PHF decreased ROS accumulation up to 36.7% and membrane disruption up to 30.7% in a dose- and pH-dependent manner. Two mechanisms helped to explain the role of PHF in alleviating Cd toxicity to yeasts: PHF decreased Cd-induced oxidative stress and bound significant amounts of Cd in the extracellular medium, reducing its bioavailability to the cells.
- Mobilidade em cidades de média dimensão: o caso da cidade de FaroPublication . Gameiro, Celeste; Pires Rosa, Manuela; Rodrigues, J. I.; Alves, R. M. A.Recentemente em Portugal, finais 2013, através do projeto de investigação INLUT - “Integração dos usos do solo e transportes em cidades de média dimensão”, que está a ser desenvolvido em parceria por quatro Universidades Portuguesas (IPCB, FAUTL, UTAD e UALG) e financiado pela FCT – Fundação para a Ciência e a Tecnologia, realizaram-se inquéritos gerais à mobilidade em quatro cidades de média dimensão (Faro, Santarém, Vila Real, e Castelo Branco) com o principal objetivo de se analisar a relação entre os usos do solo e os padrões de deslocação da população residente. Com o presente artigo pretende-se apresentar a metodologia seguida, e uma síntese dos resultados obtidos nos 1257 inquéritos à mobilidade realizados à população residente no perímetro urbano de Faro e Montenegro/Gambelas, nas seguintes variáveis: dados da amostra, identificação das áreas homogéneas da área de estudo, distribuição espacial dos inquiridos por local de residência, sexo e estrutura etária dos inquiridos, habilitações literárias, situação face ao mercado de trabalho, potencial de mobilidade, posse de veículos, número de viagens em um dia, hora de início da primeira viagem, apresentação das atitudes (perfil do inquirido), rendimento mensal liquido do aglomerado, cadeia de atividades, taxa de imobilidade, número médio de viagens, tempo médio gasto em viagens, os motivos, as cadeias de atividades realizadas, o modo de transporte escolhido, principais razões da escolha do modo de transporte, número de transbordos efetuados, entre outras. Dado que em Portugal, nas últimas duas décadas, têm vindo a ser realizados inquéritos à mobilidade geral em duas cidades de grandes dimensões: a cidade de Lisboa e a cidade do Porto com a finalidade de estudar os padrões de deslocação dos residentes e visitantes e melhorar a oferta de transportes públicos nas áreas metropolitanas destas duas grandes cidades, apresenta-se também uma breve análise comparativa entre os padrões de mobilidade da cidade de Faro, com os padrões de mobilidade da grande cidade de Lisboa.
- Lithium fluoride injection layers can form quasi-Ohmic contacts for both holes and electronsPublication . Bory, Benjamin F.; Rocha, Paulo; Janssen, Rene A. J.; Gomes, Henrique L.; De Leeuw, Dago M.; Meskers, Stefan C. J.Thin LiF interlayers are typically used in organic light-emitting diodes to enhance the electron injection. Here, we show that the effective work function of a contact with a LiF interlayer can be either raised or lowered depending on the history of the applied bias. Formation of quasi-Ohmic contacts for both electrons and holes is demonstrated by electroluminescence from symmetric LiF/polymer/LiF diodes in both bias polarities. The origin of the dynamic switching is charging of electrically induced Frenkel defects. The current density-electroluminescence-voltage characteristics can qualitatively be explained. The interpretation is corroborated by unipolar memristive switching and by bias dependent reflection measurements. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.
- Padrões de mobilidade urbana num contexto de crise económica e social: o caso da cidade de FaroPublication . Pires Rosa, Manuela; Gameiro, Celeste; Rodrigues, J. I.; Alves, R. M. A.; Serdoura , F. M. C.; Ramos, R. A. R.; Rodrigues, D. S.; Rodrigues da Silva, A. N.; Rodrigues da Silva, A. N.Na última década, em Portugal, no domínio da gestão da mobilidade urbana, tem vindo a ocorrer, progressivamente, uma mudança de abordagem de provisão de transporte, tradicionalmente focalizada no tráfego e transporte, para uma sustentabilidade orientada, valorizadora dos modos suaves e transportes coletivos. Paralelamente têm sucedido profundas mudanças económicas e sociais, registando-se atualmente uma situação de crise económica que tem tido grandes repercussões no poder de compra dos portugueses e no incremento das taxas de desemprego. Neste contexto, ocorre uma efetiva mudança dos padrões de mobilidade dos portugueses, expressa por uma redução da utilização do transporte individual motorizado, nomeadamente, à escala urbana. A análise é desenvolvida considerando a cidade de Faro e é suportada por inquéritos à mobilidade realizados nos anos de 2001 e 2013.
- Behavioural stress responses predict environmental perception in European sea bass (Dicentrarchus labrax)Publication . Millot, Sandie; Cerqueira, Marco; Castanheira, Maria Filipa; Overli, Oyvind; Oliveira, Rui F.; Martins, Catarina I. M.Individual variation in the response to environmental challenges depends partly on innate reaction norms, partly on experience-based cognitive/emotional evaluations that individuals make of the situation. The goal of this study was to investigate whether pre-existing differences in behaviour predict the outcome of such assessment of environmental cues, using a conditioned place preference/avoidance (CPP/CPA) paradigm. A comparative vertebrate model (European sea bass, Dicentrarchus labrax) was used, and ninety juvenile individuals were initially screened for behavioural reactivity using a net restraining test. Thereafter each individual was tested in a choice tank using net chasing as aversive stimulus or exposure to familiar conspecifics as appetitive stimulus in the preferred or non preferred side respectively (called hereafter stimulation side). Locomotor behaviour (i.e. time spent, distance travelled and swimming speed in each tank side) of each individual was recorded and analysed with video software. The results showed that fish which were previously exposed to appetitive stimulus increased significantly the time spent on the stimulation side, while aversive stimulus led to a strong decrease in time spent on the stimulation side. Moreover, this study showed clearly that proactive fish were characterised by a stronger preference for the social stimulus and when placed in a putative aversive environment showed a lower physiological stress responses than reactive fish. In conclusion, this study showed for the first time in sea bass, that the CPP/CPA paradigm can be used to assess the valence (positive vs. negative) that fish attribute to different stimuli and that individual behavioural traits is predictive of how stimuli are perceived and thus of the magnitude of preference or avoidance behaviour.
- Novel galanin receptors in teleost fish: identification, expression and regulation by sex steroidsPublication . Martins, Rute S. T.; Pinto, Patricia IS; Guerreiro, P. M.; Zanuy, Silvia; Carrillo, Manuel; Canario, Adelino V. M.In fish, the onset of puberty, the transition from juvenile to sexually reproductive adult animals, is triggered by the activation of pituitary gonadotrophin secretion and its timing is influenced by external and internal factors that include the growth/adiposity status of the animal. Kisseptins have been implicated in the activation of puberty but peripheral signals coming from the immature gonad or associated to the metabolic/nutritional status are also thought to be involved. Additionally, there is evidence that the galaninergic system in the brain and testis of pre-pubertal male sea bass is a possible mediator involved in the translation of somatic signals leading to gonadal maturation. Here, the transcripts for four galanin receptors (GALR), named GALR1a, 1b, 2a and 2b, were isolated from European sea bass, Dicentrarchus labrax. Phylogenetic analysis confirmed the previously reported duplication of GALR1 in teleost fish, and unravelled the duplication of GALR2 in teleost fish and in some tetrapod species. Comparison with human showed that the key amino acids involved in ligand binding are present in the corresponding GALR1 and GALR2 orthologues. Transcripts for all four receptors are expressed in brain and testes of adult fish with GALR1a and GALR1b abundant in testes 15 and hardly detected in ovaries. In order to investigate whether GALR1 dimorphic expression was dependent on steroid context we evaluated the effect of 11-ketotestosterone and 17β-estradiol treatments on the receptor expression in brain and testes of pre-pubertal males. Interestingly, steroid treatments had no effect on the expression of GALRs in the brain while in the testes, GALR1a and GALR1b were significantly up regulated by 11KT. Altogether, these results support a role for the galaninergic system, in particular the GALR1 paralog in fish reproductive function.
- Vera e Fábio: novas pinceladas nos Frescos de PompeiaPublication . Nogueira, AdrianaLívia Borges apresenta um segundo romance da saga Frescos de Pompeia. Digo «um» segundo e não «o» segundo, pois, como a autora tem revelado nas apresentações, quer de Julia Felix, o seu primeiro romance (v. Cultura.Sul, de agosto de 2011), quer deste, os seus livros foram desenhados como fazendo parte de um todo (alguns já estão mesmo completamente escritos), constituindo, no final, um vasto fresco da vida em Pompeios*, na época imperial. Este segundo romance de Lívia Borges tem como personagem principal uma escrava, que aparecia muito secundariamente no primeiro romance. Por seu lado, Julia Felix entra aqui, não como protagonista, mas como antagonista e propiciadora de muitas situações difíceis que Vera tem de viver e suportar. Uma forma inteligente de nos prender a uma coleção e de nos fazer ansiar pelo volume seguinte. E, apesar de haver uma relação lógica entre eles, a nossa ordem de leitura pode ser variável. Um desafio.
- Changes in the gene expression profiles of the brains of male European eels (Anguilla anguilla) during sexual maturationPublication . Churcher, Allison; Pujolar, Jose M.; Milan, Massimo; Hubbard, Peter; Martins, Rute S. T.; L. Saraiva, João; Huertas, Mar; Bargelloni, Luca; Patarnello, T.; Marino, Ilaria A. M.; Zane, Lorenzo; Canario, Adelino V. M.Background: The vertebrate brain plays a critical role in the regulation of sexual maturation and reproduction by integrating environmental information with developmental and endocrine status. The European eel Anguilla anguilla is an important species in which to better understand the neuroendocrine factors that control reproduction because it is an endangered species, has a complex life cycle that includes two extreme long distance migrations with both freshwater and seawater stages and because it occupies a key position within the teleost phylogeny. At present, mature eels have never been caught in the wild and little is known about most aspects of reproduction in A. anguilla. The goal of this study was to identify genes that may be involved in sexual maturation in experimentally matured eels. For this, we used microarrays to compare the gene expression profiles of sexually mature to immature males. Results: Using a false discovery rate of 0.05, a total of 1,497 differentially expressed genes were identified. Of this set, 991 were expressed at higher levels in brains (forebrain and midbrain) of mature males while 506 were expressed at lower levels relative to brains of immature males. The set of up-regulated genes includes genes involved in neuroendocrine processes, cell-cell signaling, neurogenesis and development. Interestingly, while genes involved in immune system function were down-regulated in the brains of mature males, changes in the expression levels of several receptors and channels were observed suggesting that some rewiring is occurring in the brain at sexual maturity. Conclusions: This study shows that the brains of eels undergo major changes at the molecular level at sexual maturity that may include re-organization at the cellular level. Here, we have defined a set of genes that help to understand the molecular mechanisms controlling reproduction in eels. Some of these genes have previously described functions while many others have roles that have yet to be characterized in a reproductive context. Since most of the genes examined here have orthologs in other vertebrates, the results of this study will contribute to the body of knowledge concerning reproduction in vertebrates as well as to an improved understanding of eel biology.
- Sebenta das aulas teóricas/teórico práticas para " Química Inorgânica"Publication . Wang, WenliSebenta das Aulas Teóricas /Teórico-práticas Curso: Farmácia Ano Letivo 2014/2015