995 resultados para 258
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A nanocomposite porous electrode structure consisting of hierarchical iodine-doped zinc oxide (I-ZnO) aggregates combined with the two simple solution-processed interfacial modifications i.e. a ZnO compact layer (CL) and a TiO2 protective layer (PL) has been developed in order to understand electron transport and recombination in the photoanode matrix, together with boosting the conversion efficiency of I-ZnO based dye-sensitized solar cells (DSCs). Electrochemical impedance spectra demonstrate that ZnO CL pre-treatment and TiO2 PL post-treatment synergistically reduce charge-transfer resistance and suppress electron recombination. Furthermore, the electron lifetime in two combined modifications of IZnO + CL + PL photoelectrode is the longest in comparison with the other three photoelectrodes. As a consequence, the overall conversion efficiency of I-ZnO + CL + PL DSC is significantly enhanced to 6.79%, with a 36% enhancement compared with unmodified I-ZnO DSC. Moreover, the stability of I-ZnO + CL + PL cell is improved as compared to I-ZnO one. The mechanism of electron transfer and recombination upon the introduction of ZnO CL and TiO2 PL is also proposed in this work.
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To gain insight into IL5 receptor subunit recruitment mechanism, and in particular the experimentally elusive pathway for assembly of signaling subunit beta(c), we constructed a soluble beta(c) ectodomain (s(beta)(c)) and developed an optical biosensor assay to measure its binding kinetics. Functionally active s(beta)(c) was anchored via a C-terminal His tag to immobilized anti-His monoclonal antibodies on the sensor surface. Using this surface, we quantitated for the first time direct binding of s(beta)(c) to IL5R(alpha) complexed to either wild-type or single-chain IL5. Binding was much weaker if at all with either R(alpha) or IL5 alone. Kinetic evaluation revealed a moderate affinity (0.2-1 microM) and relatively fast off rate for the s(beta)(c) interaction with IL5:R(alpha) complexes. The data support a model in which beta(c) recruitment occurs with preformed IL5:R(alpha) complex. Dissociation kinetics analysis suggests that the IL5-alpha-beta(c) complex is relatively short-lived. Overall, this study solidifies a model of sequential recruitment of receptor subunits by IL5, provides a novel biosensor binding assay of beta(c) recruitment dynamics, and sets the stage for more advanced characterization of the roles of structural elements within R(alpha), beta(c), and cytokines of the IL5/IL3/GM-CSF family in receptor recruitment and activation.
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Objectives: Given the clinical and pathological similarities between age-relatedmacular degeneration (AMD) and Alzheimer disease (AD), to assess whether AMDassociatedsingle nucleotide polymorphisms (SNPs), including those from complementrelatedgenes, are associated with AD.
Design: A case-control association study-typedesign.
Setting: A UK tertiary care dementia clinic.
Participants: 322 cognitivelynormal participants and 258 cases with a clinical diagnosis of AD.
Measurements:Polymorphisms in the following genes were studied: CFH, ARMS2, C2/CFB, C3, CFI/PLA2G12a, SERPING1, TLR3, TLR4, CRP, APOE, and TOMM40. Haplotypes were analysedfor CFH, TOMM40, and APOE. Univariate analysis was performed for each geneticchange and case-comparator status, and then correction for multiple testing performed.
Results: The presence of an ε4 APOE allele was significantly associated with AD. Noassociation was evident between CFH SNPs or haplotypes, or other AMD-associated SNPstested, and AD. The exceptions were TOMM40 SNPs, which were associated with AD evenafter correction for multiple comparisons. The associations disappeared, however, whenentered into a regression model including APOE genotypes.
Conclusions: The resultsfor most SNPs tested, as well as CFH haplotypes, are novel. The functional effects ofabnormal complement activity in AD’s pathogenesis may be contradictory, butmethodological reasons may underlie the lack of association—for example, geneticchanges other than SNPs being involved.
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Objective: Regular follow-up is essential to successful management of childhood cataract. We sought to assess whether a mobile phone short message service (SMS) for parents of children with cataract could improve follow-up adherence and the proportion of procedures performed in timely fashion. Design: Randomized, controlled trial. This trial is registered with ClinicalTrials.gov, NCT01417819. Participants: We included 258 parent-child pairs involved in the Childhood Cataract Program of the Chinese Ministry of Health. Methods: Participants were randomized (1:1) to a mobile phone SMS intervention or standard follow-up appointments. All participants were scheduled to attend <4 follow-up appointments according to the protocol. Parents in the intervention group received SMS automated reminders before scheduled appointments. The control group parents did not receive SMSs or any alternative reminder of scheduled appointments. Regular ocular examinations and analyses were performed by investigators masked to group allocation; however, study participants and the manager in charge of randomization and sending SMSs were not masked. Main Outcome Measures: Number of follow-up appointments attended, additional surgeries, laser treatments, changes in eyeglasses prescription, and occurrence of secondary ocular hypertension. Results: Among parent-child participants, 135 were randomly assigned to the SMS intervention and 123 to standard appointments. Attendance rates for the SMS group (first visit, 97.8%; second, 91.9%; third, 92.6%; fourth, 83%) were significantly higher than those for the control group (first visit, 87.8%; second, 69.9%; third, 56.9%; fourth, 33.3%). The increase in attendance rate for total number of follow-up visits with SMS reminders was 47.2% (relative risk [RR] for attendance, 1.47; 95% confidence interval [CI], 1.16-1.78; P = 0.003). The number needed to remind (NNR) to gain 1 additional visit by 1 child was 3 (95% CI, 1.8-4.2). A total of 247 clinical interventions were carried out in the SMS group and 134 in the control group (RR, 1.68; 95% CI, 1.37-1.99; P = 0.007). The NNR to result in 1 additional clinical intervention was 5 (95% CI, 3.5-6.5). Conclusions: The SMS reminders significantly improved follow-up adherence in pediatric cataract treatment. Using readily available mobile phone resources may be an effective and economic strategy to improve management of childhood cataract in China. Financial Disclosure(s): The authors have no proprietary or commercial interest in any of the materials discussed in this article. © 2012 American Academy of Ophthalmology.
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PURPOSE: To assess determinants of spectacle acceptance and use among rural Chinese children. METHODS: Children with uncorrected acuity < or = 6/12 in either eye and whose presenting vision could be improved > or = 2 lines with refraction were identified from a school-based sample of 1892 students. Information on obtaining glasses and the benefits of spectacles was provided to children, families, and teachers. Purchase of new spectacles and reasons for nonpurchase were assessed by direct inspection and interview 3 months later. RESULTS: Among 674 (35.6%) children requiring spectacles (mean age, 14.7 +/- 0.8 years), 597 (88.6%) were followed up. Among 339 children with no glasses at baseline, 30.7% purchased spectacles, whereas 43.2% of 258 children with inaccurate glasses replaced them. Most (70%) subjects paid US$13 to $26. Among children with bilateral vision < or = 6/18, 45.6% bought glasses. In multivariate models, presenting vision < 6/12 (P < 0.009), refractive error < -2.0 D (P < 0.001), and amount willing to pay for glasses (P = 0.01) were predictors of purchase. Reasons for nonpurchase included satisfaction with current vision (78% of those with glasses at baseline, 49% of those without), concerns over price or parental refusal (18%), and fear glasses would weaken the eyes (13%). Only 26% of children stated that they usually wore their new glasses. CONCLUSIONS: Many families in rural China will pay for glasses, though spectacle acceptance was < 50%, even among children with poor vision. Acceptance could be improved by price reduction, education showing that glasses will not harm the eyes, and parent-focused interventions.
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Attitudes towards a regional military force are of paramount importance when exploring public support for regional integration. Until now, however, scholarly research has not considered the influence of attitudes towards a regional military mechanism in the sub-Saharan African context. Using Afrobarometer data, we demonstrate that military concerns are vital when exploring Tanzanian attitudes towards the proposed political federation of the East African Community (EAC), the East African Federation (EAF). More specifically, opposition to military cooperation strongly influences Tanzanian scepticism of the EAF. This finding is highly relevant given that referendums in the participating member states must be passed to facilitate political integration. Heightened opposition towards military cooperation raises the possibility of the public rejecting a politically integrated EAC. This poses a potential obstacle to the implementation of joint security policies and crucial mechanisms to provide a more stable region at large. We account for alternative explanations of Tanzanian opinion formation and reflect on the strength of military-orientated concerns for investigating public support for the East African project specifically and regional integration in sub-Saharan Africa more widely.
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La publicación ‘La accesibilidad y el diseño universal entendido por todos. De cómo Stephen Hawking viajó por el espacio’ es un libro al alcance de todos los públicos para acercarse a la accesibilidad universal, al diseño para todos y a la importancia de la igualdad de oportunidades para todas las personas. Sin duda, el autor se esfuerza con este libro en recopilar y sintetizar gran parte del conocimiento que había disperso en la materia, para condensarlo en una obra amena y apta para cualquier persona, independientemente si es profesional de la accesibilidad o está relacionada con el mundo de la discapacidad.
Família, psicopatologia e resiliência na adolescência: do risco psicossocial ao percurso delinquente
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Tese de dout., Psicologia, Faculdade de Ciências Humanas e Sociais, Univ. do Algarve, 2007
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Poker is the gambling game that is currently gaining the most in popularity. However, there is little information on poker players' characteristics and risk factors. Furthermore, the first studies described poker players, often recruited in universities, as an homogeneous group who played in only one of the modes (land based or on the Internet). This study aims to identify, through latent class analyses, poker player subgroups. A convenience sample of 258 adult poker players was recruited across Quebec during special events or through advertising in various media. Participants filled out a series of questionnaires (Canadian Problem Gambling Index, Beck Depression, Beck Anxiety, erroneous belief and alcohol/drug consumption). The latent class analysis suggests that there are three classes of poker players. Class I (recreational poker players) includes those who have the lowest probability of engaging intensively in different game modes. Participants in class II (Internet poker players) all play poker on the Internet. This class includes the highest proportion of players who consider themselves experts or professionals. They make a living in part or in whole from poker. Class III (multiform players) includes participants with the broadest variety of poker patterns. This group is complex: these players are positioned halfway between professional and recreational players. Results indicate that poker players are not an homogeneous group identified simply on the basis of the form of poker played. The specific characteristics associated with each subgroup points to vulnerabilities that could potentially be targeted for preventive interventions.
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Dissertação de mestrado, Tecnologia dos Alimentos, Instituto Superior de Engenharia, Universidade do Algarve, 2014
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Die alltägliche Konfrontation mit gesellschaftlichen Tabus wie Alter, Krankheit, Tod, die Arbeit zwischen "Macht und Ohnmacht" verlangt von den Pflegenden ein hohes Maß an sozialer und personaler Kompetenz. Das szenische Lernen bzw. Spiel ist ein Ansatz, der sich hervorragend zur Förderung dieser Schlüsselqualifikationen eignet. In diesem Aufsatz werden zunächst die allgemein didaktischen Ursprünge und Hintergründe szenischen Lernens bzw. Spiels dargestellt, um anschließend seine pflegedidaktische Auslegung und Akzentuierung zu charakterisieren. Zum Schluss wird anhand der Lerneinheit „Reflexion der praktischen Ausbildung“ aufgezeigt, wie mit ausgewählten szenischen Spielverfahren in der pflegepädagogischen Praxis gearbeitet werden kann.
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The framers of the American Constitution devised a singular bicameral legislative body, which invested substantial power in both a broadly representative lower chamber and a second "deliberative" chamber that was both insulated from the voters and unrepresentative of the population as a whole. Until the early 20th Century, the singular U.S. Congress changed little, but with growing national responsibilities, it sought to construct organizational forms that could address a consistently stronger executive. Since the 1980s, the Congress has relied increasingly on stronger parties to organize its activities. This development, embraced in turn by Democrats and Republicans, has led to changes that have edged the Congress in the direction of parliamentary democracies. We conclude this analysis has real, but limited utility, as congressional party leaders continue to barter for votes and, in the context, of narrow chamber majorities, often rely heavily on presidential assistance on divisive issues that are important to their party brand. Yet, the traditional features of the American separated system - bicameralism, the committee systems, and the centrifugal forces emanating from diverse congressional districts, increasingly complex policy issues, and the fear of electoral retribution - also remain strong, and effectively constrain the influence of leaders.'Qualified exceptionalism' thus most aptly describes the contemporary American Congress, which remains 'exceptional,' but less than unique, as it responds to many of the same forces, in some of the same ways (e.g., strong parties), as do many other representative assemblies around the world.
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US presidents have expanded executive power in times of war and emergency,sometimes aggressively so. This article builds on the application of punctuated equilibria theory by Burnham (1999 and Ackerman (1999). Underpinning this theory is the notion that rapid changes in - or external shocks to - domestic and international society impose new and insistent demands on the state. In so doing, they produce important and decisive moments of institutional mobilization and creativity, disrupt a pre-existing, relatively stable, equilibrium between the Congress and the president, and precipitate decisions or nondecisions by the electorate and political leaders that define the contours for action when the next crisis or external shock occurs. The article suggests that the combination of President George W. Bush's presidentialist doctrine, 9/11 and the 'war' on terror has consolidated a new, constitutional equilibrium. While some members of Congress contest the new order, the Congress collectively has acquiesced in its own marginalization. The article surveys a wide range of executive power assertions and legislative retreats. It argues that power assertions generally draw on precedent: on, for example, a tradition of wartime presidential extraconstitutional leadership extending to presidents, such as John Adams and Abraham Lincoln,as well as to Cold War and post-Cold War presidentialism.
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Where is the consumer represented within the discourses of Relationship Marketing? In our paper we deconstruct and critically (but productively) interrogate current Relationship Marketing discourse; and we argue for reconceptualising RM as a field of study through a transformatory process which involves the subversive reading of its academic texts. We argue that the consumer is silenced within relationship marketing discourse in a way that is fundamentally analogous with the gynopia (absence of women) in early sociological enquiry. Given that the means of transformation can potentially be found within contemporary feminist research, one of the main aims of this paper is to examine the parameters of feminist research and theory by presenting and explaining three representative frameworks (Fonow & Cook 1991, Maynard & Purvis 1994 and Harding 1988). The interrogative questions generated from the reading of feminist texts provide a framework to enable a close reading of RM ‘texts’. Using a form of discourse analysis, we read both ‘with the text’ and ‘against the grain’ (Tonkiss 1998:258) looking for ‘silences and gaps’ and making ‘conjectures about alternative accounts which are excluded by omission’ as well as those deliberately ‘countered by rhetoric’ (Tonkiss 1998:258). By striking together feminist methodology and a selected Relationship Marketing text to see if they spark (Brown 1999) our stance is activist and our purpose is to accelerate a restoration of the consumer’s voice as a central theoretical concern of this branch of Marketing.