834 resultados para Behaviour change


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The purpose of this research is fourfold. First, to investigate whether the determinants of international equity investment differ between investors with different degrees of information, experience and sophistication. For this purpose, the determinants of international equity investment of institutional and noninstitutional investors from 20 OECD countries, in the period 2001-2009, were analysed and compared. The results show that there are significant differences in the determinants of international equity investment between institutional and noninstitutional investors. Particularly, noninstitutional investors exhibit a more pronounced preference for equities of geographical nearby, contiguous and more transparent countries than institutional investors, suggesting that the effect of information costs and familiarity on international equity investment is stronger for less informed, experienced and sophisticated investors. Moreover, the preference for more developed equity markets and the contrarian behaviour are more severe for noninstitutional investors. Hence, the heterogeneity of institutional and noninstitutional investors in international equity investment is not negligible and therefore should be taken into account. Second, to investigate whether the determinants of international bond investment differ between investors with different degrees of information, experience and sophistication. For this purpose, the determinants of international bond investment of institutional and noninstitutional investors from 20 OECD countries, in the period 2001-2009, were analysed and compared. The results show that there are few significant differences in the determinants of international bond investment between institutional and noninstitutional investors. Particularly, the preference for bonds of more transparent countries and the return chasing behaviour are more pronounced for noninstitutional investors, whereas the preference for bonds with lower risk diversification potential is more pronounced for institutional investors. Hence, not only the results for international bond investment do not allow to support (or reject) the argument that information costs and familiarity are more important for less informed, experienced and sophisticated investors, but also they are contrary to the idea that financial variables, namely return and risk diversification, are more important for more informed, experienced and sophisticated investors. Third, to investigate whether the determinants of international equity investment differ from the determinants of international bond investment. For this purpose, the determinants of both international equity and bond investment of institutional and noninstitutional investors from 20 OECD countries, in the period 2001-2009, were analysed and compared. The results show that, although the effect of information costs on international equity investment tends to be stronger than on international bond investment, the differences between assets are not usually statistically significant, especially when the influence of financial variables is taken into account. Hence, it is not possible to conclude that international equity investment is much more information intensive than international bond investment, as suggested by Gehrig (1993) and Portes, Rey and Oh (2001), among others. Fourth, to investigate whether the flight to quality phenomenon is also observable in international investment and whether the flight to quality phenomenon is more pronounced for more sophisticated than for less sophisticated investors. For this purpose, a two-factor and three-factor ANOVA models, respectively, were applied to the international equity and bond investment of institutional and noninstitutional investors from 20 OECD countries in the period 2001-2009. The results suggest that the flight to quality phenomenon is also observable in international investment, as a change from business cycle of expansion to recession causes investors to significantly decrease the average weight invested in more risky assets (equities) and increase the average weight invested in less risky assets (bonds). The results also show that the variation on the average weight assigned to each type of asset, due to changes in business cycles, is significantly stronger for institutional investors than for noninstitutional investors, thereby suggesting that the flight to quality phenomenon is more pronounced for more sophisticated than for less sophisticated investors.

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We propose new theoretical models, which generalize the classical Avrami-Nakamura models. These models are suitable to describe the kinetics of nucleation and growth in transient regime, and/or with overlapping of nucleation and growth. Simulations and predictions were performed for lithium disilicate based on data reported in the literature. One re-examined the limitations of the models currently used to interpret DTA or DSC results, and to extract the relevant kinetic parameters. Glasses and glass-ceramics with molar formulation 0.45SiO2? (0.45-x)MgO?xK2O?0.1(3CaO.P2O5) (0?x?0.090) were prepared, crystallized and studied as potential materials for biomedical applications. Substitution of K+ for Mg2+ were used to prevent devritification on cooling, to adjust the kinetics of crystallization and to modify the in vitro behaviour of resulting biomaterials. The crystallization of the glass frits was studied by DTA, XRD and SEM. Exothermic peaks were detected corresponding to bulk crystallization of whitlockite-type phosphate, Ca9MgK(PO4)7, at approximately 900ºC, and surface crystallization of a predominant forsterite phase (Mg2SiO4) at higher temperatures. XRD also revealed the presence of diopside (CaMgSi2O6 in some samples. The predominant microstructure of the phosphate phase is of the plate-type, seemingly crystallizing by a 2-dimensional growth mechanism. Impedance spectroscopy revealed significant changes in electrical behaviour, associated to crystallization of the phosphate phase. This showed that electrical measurements can be used to study the kinetics of crystallization for cases when DTA or DSC experiments reveal limitations, and to extract estimates of relevant parameters from the dependence of crystallization peak temperature, and its width at half height. In vitro studies of glasses and glass-ceramics in acelular SBF media showed bioactivity and the development of apatite layers The morphology, composition and adhesion of the apatite layer could be changed by substitution of Mg2+ by K+. Apatite layers were deposited on the surface of glass-ceramics of the nominal compositions with x=0 and 0.09, in contact with SBF at 37ºC. The adhesion of the apatite layer was quantified by the scratch test technique, having been related with SBF?s immersion time, with composition and structure of the glass phase, and with the morphology of the crystalline phase of the glass-ceramics. The structure of three glasses (x=0, 0.045 and 0.090) were investigated by MAS-NMR ( 29Si and 31P), showing that the fraction of Q3 structural units increases with the contents of Mg, and that the structure of these glasses includes orthophosphate groups (PO43-) preferentially connected to Ca2+ ions. Mg2+ ions show preference towards the silicate network. Substitution of Mg2+ by K+ allowed one to change the bioactivity. FTIR data revealed octacalcium phosphate precipitation (Ca8H2(PO4)6.5H2O) in the glass without K, while the morphology of the layer acquires the shape of partially superimposed hemispheres, spread over the surface. The glasses with K present a layer of acicular hidroxyapatite, whose crystallinity and needles thickness tend to increase along with K content.

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ABSTRACTThis paper reports an empirical case study on the interface between microfinance and climate change actions. Climate change, which until recently seemed a luxury for the microfinance sector, now appears to be crucial for its future. For their low adaptive capacity, the millions of microfinance clients worldwide happen to be the most vulnerable to a changing climate. However, such an arena is still blurred from an academic viewpoint, and inexistent among Brazilian academia. Therefore, by investigating Brazil’s largest rural MFI, Agroamigo, we aim at providing an empirical contribution to green microfinance. The main conclusion is that, albeit Agroamigo offers important links to climate change initiatives, it will need to take better account of specific vulnerabilities and risks to protect its portfolio and clients better from climate change impacts.

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Revista Lusófona de Ciências Sociais

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RESUMO: Considerando a identidade como um processo dinâmico de interacção social, afastando-nos da ideia de identidades pré-estabelecidas, ancoradas numa visão essencialista e, aproximando-nos de uma identidade profissional que se constrói através de sucessivas interacções, procurámos conhecer a identidade profissional do docente de enfermagem. Convictos de que o estudo da identidade pode oscilar entre um pólo individual e um estrutural, optámos pela dimensão biográfica como eixo estruturante deste trabalho. Efectuaram-se oito biografias a docentes integrados no conceito de perito com uma profissionalidade reflectida. Utilizámos ainda o focus group como método complementar. Constatámos que os actores deste estudo se sentem enfermeiros, embora a sua área de actuação seja a docência. Destacam a integração do ensino de enfermagem no ensino superior como determinante na mudança da sua representação social. Todos estes docentes se incluem nos grupos que apresentam um estatuto da identidade realizado ou outorgado. Das competências que devem estar presentes no docente de enfermagem, salientam-se a comunicação, actualização científica e relação, capazes de promover um ambiente que propicie as aprendizagens significativas, de internacionalização, de investigação, como um modelo de conduta a seguir, que participe na vida da organização e seja capaz de motivar o outro, mas sobretudo que seja um bom enfermeiro. ABSTRACT: Considering identity as a social dynamic integration process, departing from the concept of pre-established identities anchored in an essentialist vision, and approaching a professional identity built trough successive interaction, we aimed to know the professional identity of the nursing teacher. Believing that the identity study may oscillate between an individual and a structural pole, we have chosen the biographic dimension as the structural axis for this assignment. Eight biographies from teachers integrated in the expert with a reflective professional identity have been made. We have also used the focus group as a complementary method. We have seen that the actors of this study feel themselves as nurses although their working area is teaching. They point out the higher teaching of Nursing as a determinant in the change of their social representation. All of these teachers are included in the groups that present an identity status that has been fulfilled or attributed. From the skills that should be present in the nursing teacher, communication, scientific knowledge and relationship are indicated when these are able to provide significant learning, internationalization and research as a behaviour model to be followed regarding the life of the organization and that might incentive others, but above as a way to be a good nurse.

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O tema a que se refere este estudo foi escolhido dada a atualidade e a pertinência da temática da violência doméstica na nossa sociedade, sendo reconhecida e assumida como um crime público e uma forma grave de violação dos direitos humanos. Este estudo tem como objetivo analisar, identificar e compreender as representações sociais de um grupo de mulheres migrantes brasileiras vítimas de violência doméstica. Do ponto de vista metodológico o estudo é qualitativo recorrendo aos testemunhos pessoais através de uma amostra de 10 participantes no qual foi aplicada a técnica de recolha de dados, a entrevista. Os conteúdos das entrevistas foram analisados através dos softwares Textstat 2.9 e do Freemind 1.1. Os resultados demonstraram que o tipo de violência doméstica preponderante é a violência física e as causas da violência doméstica foram, essencialmente, o álcool e as drogas. O agressor foi representado pelas mulheres através de objetivações negativas e afetivas, sendo que a maioria das mulheres acreditam na mudança do comportamento violento do agressor. No que tange às representações acerca do futuro, observaram-se representações ancoradas na resiliência e na falta de perspetivas de futuro. Os resultados são indicadores que as representações sociais que as mulheres brasileiras têm dos brasileiros são positivas e dos portugueses negativas, sendo o suporte social sustentado na família, nos amigos e nas instituições de apoio à vítima. Os resultados demonstram que as mulheres possuem a representação de que os portugueses e os brasileiros são ambos violentos, e constatou-se que as representações sociais que as mulheres possuem em relação à tolerância são objetivações positivas. Verificou-se também que a violência contra a mulher reflete um fenómeno complexo e multifacetado.

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Resting adults Culicidae were collected from January 1992 through January 1993 in several habitats of the Ribeira Valley region. The diversity of species found among them suggested that the vegetation remaining within human settlements favored the survival and the population increase of some mosquitoes. Among there are: Ae. scapularis, Ae. serratus, Cx. (Culex), Cx. nigripalpus and Cx. (Melanoconion) such as Cx. ribeirensis. That preservation role may be attributed to the rearing of livestock and the consequent increase in the number of blood sources. These species may be classified as hemisynanthropes and Cx. oedipus apparently evolving to the eusynanthropic status. On the other hand, An. cruzii showed an asynanthropic behaviour, with a low degree of survival in the modified human environment. Epidemiological implications of the data are mentioned.

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The tris(1-pyrazolyl)methanesulfonate lithium salt Li(Tpms) [Tpms = SO3C(pz)(3)-] reacts with [Mo(CO)(6)] in NCMe heated at reflux to yield Li[Mo(Tpms)(CO)(3)] (1), which, upon crystallization from thf, forms the coordination polymer [Mo(Tpms)(CO)(2)(mu-CO)Li(thf)(2)](n) (2). Reaction of 1 with I-2, HBF4 or AgBF4 yields [Mo(Tpms)I(CO)(3)] (3), (Mo(Tpms)-H(CO)(3)] (5) or (Mo(Tpms)O-2](2)(mu-O) (7), respectively. The high-oxidation-state dinuclear complexes [{Mo(Tpms)O(mu-O)}(2)] (4) and [{Mo(tpms)OCl)(2)](mu-O) (6) are formed upon exposure to air of solutions of 3 and 5, respectively. Compounds 1-7, which appear to be the first tris(pyrazolyl)methanesulfonate complexes of molybdenum to be reported, were characterized by IR, H-1 and C-13 NMR spectroscopy, ESI-MS, elemental analysis, cyclic voltammetry and, in the cases of Li(Tpms) and compounds 2, 4.2CH(3)CN, 6.6CHCl(3) and 7, by X-ray diffraction analyses. Li(Tpms) forms a 1D polymeric structure (i.e., [Li(tpms)](n)} with Tpms as a tetradentate N2O2 chelating ligand that bridges two Li cations with distorted tetrahedral coordination. Compound 2 is a 1D coordination polymer in which Tpms acts as a bridging tetradentate N3O ligand and each Li(thf)(2)(+) moiety is coordinated by one bridging CO ligand and by the sulfonyl group of a contiguous monomeric unit. In 4, 6 and 7, the Tpms ligand is a tridentate chelator either in the NNO (in 4) or in the NNN (in 6 and 7) fashion. Complexes 1, 3 and 5 exhibit, by cyclic voltammetry, a single-electron oxidation at oxidation potential values that indicate that the Tpms ligand has an electron-donor character weaker than that of cyclopentadienyl.

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Results obtained with catches performed at several sites of the Ribeira Valley, SP (Brazil) are reported. Collections with Shannon type traps showed a concentration of An.albitarsis s.l. in the Experimental Farm of Pariquera-Açu County, associated with the development of irrigated rice cultivation. Two species of the complex, named A and B, were recognized. Species B predominated in the samples. Indoor and outdoor crepuscular human bait captures were performed a the domiciliary environment. The two species showed a generally low William's media valve of 0.2, the highest value obtained was 1.6. No differences were found between indoor and outdoor behaviours between the two species of the complex.

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A study of Spissipes Section of Culex (Melanoconion) adults behaviour was carried out from August 1992 through December 1993 in human dominated (anthropic) environment in the Ribeira Valley, S.Paulo State, Brazil. By sampling at several sites it the dominance of Culex ribeirensis and Cx. sacchettae became evident even through a total number of ten species was recorded. Those two mosquitoes showed a clear tendency to frequent the domiciliary environment where they were caught, both indoor and outdoor, through the use of the human bait. In the outside environments, the residual patchy forests seems to display a concentration role, from which these adults spread to the open land and reach the dwellings. As their vector competence has been demonstrated through the virus isolations in natural conditions, it is advisable to pay attention to the presence of these mosquitoes in the man-made environment.

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A survey of adult behaviour of Culex (Culex) species was carried out from August 1992 through December 1993 in a human modified (anthropic) environment in the Ribeira Valley, S.Paulo State, Brazil. Culex nigripalpus dominated the catches at several sites and it's tendency to increase in the anthropic environment became quite clear. Nevertheless no high level of synanthropy was demonstrated. So it seems that the mosquito may have a restricted role in natural arbovirus cycles. Nonetheless, Cx. nigripalpus must be considered a potential vector of arboviruses, especially St. Louis encephalitis virus outside dwellings.