968 resultados para Rejection by peers
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Objective: Using longitudinal and prospective measures of trauma during childhood, the authors assessed the risk of developing psychotic symptoms associated with maltreatment, bullying, and accidents in a nationally representative U. K. cohort of young twins. Method: Data were from the Environmental Risk Longitudinal Twin Study, which follows 2,232 twin children and their families. Mothers were interviewed during home visits when children were ages 5, 7, 10, and 12 on whether the children had experienced maltreatment by an adult, bullying by peers, or involvement in an accident. At age 12, children were asked about bullying experiences and psychotic symptoms. Children`s reports of psychotic symptoms were verified by clinicians. Results: Children who experienced maltreatment by an adult (relative risk=3.16, 95% CI=1.92-5.19) or bullying by peers (relative risk=2.47, 95% CI=1.74-3.52) were more likely to report psychotic symptoms at age 12 than were children who did not experience such traumatic events. The higher risk for psychotic symptoms was observed whether these events occurred early in life or later in childhood. The risk associated with childhood trauma remained significant in analyses controlling for children`s gender, socioeconomic deprivation, and IQ; for children`s early symptoms of internalizing or externalizing problems; and for children`s genetic liability to developing psychosis. In contrast, the risk associated with accidents was small (relative risk=1.47, 95% CI=1.02-2.13) and inconsistent across ages. Conclusions: Trauma characterized by intention to harm is associated with children`s reports of psychotic symptoms. Clinicians working with children who report early symptoms of psychosis should inquire about traumatic events such as maltreatment and bullying.
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Children with developmental coordination disorder (DCD) experience difficulty participating in the typical activities of childhood and are known to have a more sedentary pattern of activities than their peers. Little research has been done to investigate the impact of these deficits on the lives of children with DCD and the importance of their participation in the typical activities of childhood. This qualitative study explored the impact of the disorder and the importance of participation for children with DCD from the perspective of the parent. Twelve in-depth interviews were conducted with parents of children with DCD who attended a university clinic specializing in using the Cognitive Orientation to daily Occupational Performance (COOP) approach, a cognitive-based intervention. Findings revealed that incompetence in everyday activities had serious negative effects for the children. Conversely, intervention that was focused on enablement at the activity and participation level had a significant positive impact on the children's quality of life. Emerging themes highlighted the notion that performance competency played an important role in being accepted by peers and being able to be part of the group. As well, parents reported that successful participation built confidence in their children and allowed them to try other new activities. The World Health Organization's International Classification of Functioning, Disability, and Health provides a unique framework for analyzing and understanding the impact of the physical disability on the lives of families with children with DCD. Results illustrate how intervention that focuses on enabling children to choose their own functional goals in the area of physical activity has important implications for enabling participation and building the social networks of children with DCD. (C) 2003 Elsevier B.V. All rights reserved.
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Dissertação apresentada na Escola Superior de Educação de Lisboa para obtenção do grau de Mestre em Educação Matemática na Educação Pré-escolar e no 1º e 2º ciclos do Ensino Básico
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For a long time the allegorical activity was considered dogmatic and equated with artistic fossilization, archaic religious propensity and lack of creativity. However, Walter Benjamin (1928) and Paul De Man (1969), among other illustrious thinkers, came to its defense, exalting, instead, its cryptic, hybrid and abstract nature, which, incidentally, are the main characteristics of modern art. “Twin Peaks – Fire Walk with Me” (David Lynch, 1992) is a wonderful object of analysis, despite being one of the most misunderstood films in the history of cinema. The fact that its narrative is a prequel to the cult television series “Twin Peaks” and incorporates many of the characters of that show, explicitly denigrating the moral image of the protagonist, Laura Palmer, brought about an intense rejection by the fans of the series, as well as the indifference of the cinephilic community in general. However, one must go deeper, in order to understand Lynch’s brave accomplishment and its artfulness. Indeed, the opus is a powerful cinematic allegory because it contains a double layer of metaphorical meaning, one of them being explicitly metacinematic. Thus, besides assuming itself as a filmic daimonic allegory, occurring in a spiritual universe of Good versus Evil, the film is also an authorial discourse on cinema itself. More specifically, it is an allegory of spectatorship, according to Robert Stam’s definition, where the existence and crossing over to “another side” duplicates the architecture of movie theatres and the psychic processes involved in film viewing.
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Renal transplant in highly sensitised patients is associated with increased morbidity. The aim of this retrospective study was to evaluate the clinical evolution of 30 highly sensitised deceased donor kidney transplants and the influence of different timing of B cell directed treatment and its importance in the outcome of these patients. All recipients had negative complement dependent lymphocytotoxicity cytotoxic T cell crossmatch and no identified anti human leucocyte antigen class I donor specific antibodies. T cell flow crossmatch was performed within 24h of transplantation with serum obtained pretransplant (historic, recent or baseline). Posttransplant flow crossmatch were performed prospectively starting on the 3rd posttransplantation day. The immunosuppressive regime included thymoglobulin, tacrolimus, mycofenolate mofetil and steroids. Positive flow crossmatch occurred in 20/29 patients by the 3rd posttransplantation day, and in 17/27 patients after the 3rd posttransplantation day. All patients were started on intravenous immunoglobulin before transplantation: in nine patients (group A) at 400mg/kg/day for five days; in the remaining 21 patients (group B), as a continued infusion of 2g/kg during 48h. In group A, Rituximab was added only in the presence of antibody mediated rejection; in group B, introduced on the 3rd posttransplantation day whenever a positive flow crossmatch (with serum obtained pre or posttransplant) was reported. Antibody mediated rejection was observed in 44.4% of patients in group A, and 19% of those in group B. Mean follow-up was 12.2±5.5 months. Overall allograft survival was 76.6%, 81% in group B, and 66.6% in group A. At last follow up, mean serum creatinine was 1.3±0.6 mg/dl. Renal transplantation with pretransplant positive flow crossmatch is highly associated with antibody mediated rejection, despite introduction of intravenous immunoglobulin pretransplantation. However high dose intravenous immunoglobulin for 48h plus Rituximab by the 3rd posttransplantation day reduce the incidence of antibody mediated rejection by more than 50% and allowed for allograft survival of 81% at one year, with an excellent renal function.
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A aprendizagem cooperativa, através da qual os alunos se ajudam no processo de aprendizagem (Argyle, 1991; Balkcom, 1992; Johnson, Johnson, & Holubec, 1994) encontra nas artes plásticas um meio privilegiado de comunicação e estimulação sensorial. Este estudo visa examinar os efeitos da implementação de um programa de atividades cooperativas no âmbito das artes plásticas sobre o processo de inclusão de crianças com Perturbação do Espectro do Autismo (PEA) nas suas turmas de ensino regular, estando sobre análise: (i) o seu envolvimento e satisfação nas atividades dinamizadas; (ii) a interação estabelecida com os pares; (iii) e o apoio/ atitudes dos pares com desenvolvimento típico na relação com os colegas com PEA. Implementado em duas turmas do 1.º Ciclo do Ensino Básico, os efeitos do programa foram estudados, mediante a implementação de um estudo de caso único, tipo AB, com um desenho de múltiplas linhas de base. Para o efeito foram analisados registos de observação de seis crianças com autismo e de seis pares que compunham as díades de trabalho; e da entrevista aos professores das turmas. A socialização e desenvolvimento de atitudes positivas por parte dos alunos com desenvolvimento típico foi também aferida através de uma entrevista dirigida aos próprios. Os resultados são sugestivos de um global aumento da interação, do envolvimento e satisfação dos alunos com PEA – registando-se maior expressão destes indicadores aquando do uso de técnicas de teor mais sensorial (como monotipia, desenho, modelagem). O programa parece ter também promovido comportamentos mais apoiantes por parte dos pares na maximização da participação dos alunos com PEA - parecendo reforçar o reconhecimento das atividades artísticas cooperativas como promotoras de relações de interajuda e de mútuo conhecimento.
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Tese de Doutoramento em Ciências da Comunicação (Especialidade em Teoria da Cultura)
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This is a study of organisational decision making among senior civil servants in the Department of Health (DOH) in relation to the acceptance of methadone maintenance as a valid treatment modality for opiate misuse in Ireland. A qualitative strategy was adopted with an emergent design and grounded theory perspective. The data was collected using a naturalistic mode of inquiry and comprised of documentary analysis and semi-structured interviews. The aspects of decision making chosen for the study were: 1. Identifying the actors involved considering the heretofore dominant 'corporation sole' culture of the Irish public administration. 2. Identifying two (out of the myriad) processes involved in decision making. 3. Identifying what theoretical model(s) of decision making most closely approximates to this case. The findings were as follows: 1. Actors involved at all levels of the decision making could be identified, albeit with some difficulty. This as a result of the strategic management initiative. Previously, it may not have been possible. Stages or phases could not, in this case, be readily identified though limitations of this study may prove significant. 2. Both the processes selected in decision-making in this case were confirmed. Personal and professional support provided by peers and seniors is crucial to decision making. Decision making does occur within networks: these tend to be those that are formally appointed rather than informal ones. 3. The model closest to that of this case was that of incremental decision making within network settings.This resource was contributed by The National Documentation Centre on Drug Use.
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Cornea transplantation is one of the most performed graft procedures worldwide with an impressive success rate of 90%. However, for "high-risk" patients with particular ocular diseases in addition to the required surgery, the success rate is drastically reduced to 50%. In these cases, cyclosporin A (CsA) is frequently used to prevent the cornea rejection by a systemic treatment with possible systemic side effects for the patients. To overcome these problems, it is a challenge to prepare well-tolerated topical CsA formulations. Normally high amounts of oils or surfactants are needed for the solubilization of the very hydrophobic CsA. Furthermore, it is in general difficult to obtain ocular therapeutic drug levels with topical instillations due to the corneal barriers that efficiently protect the intraocular structures from foreign substances thus also from drugs. The aim of this study was to investigate in vivo the effects of a novel CsA topical aqueous formulation. This formulation was based on nanosized polymeric micelles as drug carriers. An established rat model for the prevention of cornea graft rejection after a keratoplasty procedure was used. After instillation of the novel formulation with fluorescent labeled micelles, confocal analysis of flat-mounted corneas clearly showed that the nanosized carriers were able to penetrate into all corneal layers. The efficacy of a 0.5% CsA micelle formulation was tested and compared to a physiological saline solution and to a systemic administration of CsA. In our studies, the topical CsA treatment was carried out for 14 days, and the three parameters (a) cornea transparency, (b) edema, and (c) neovascularization were evaluated by clinical observation and scoring. Compared to the control group, the treated group showed a significant higher cornea transparency and significant lower edema after 7 and 13 days of the surgery. At the end point of the study, the neovascularization was reduced by 50% in the CsA-micelle treated animals. The success rate of cornea graft transplantation was 73% in treated animals against 25% for the control group. This result was as good as observed for a systemic CsA treatment in the same animal model. This new formulation has the same efficacy like a systemic treatment but without the serious CsA systemic side effects. Ocular drug levels of transplanted and healthy rat eyes were dosed by UPLC/MS and showed a high CsA value in the cornea (11710 ± 7530 ng(CsA)/g(tissue) and 6470 ± 1730 ng(CsA)/g(tissue), respectively). In conclusion, the applied formulation has the capacity to overcome the ocular surface barriers, the micelles formed a drug reservoir in the cornea from, where a sustained release of CsA can take place. This novel formulation for topical application of CsA is clearly an effective and well-tolerated alternative to the systemic treatment for the prevention of corneal graft rejection.
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It has long been standard in agency theory to search for incentive-compatible mechanisms on the assumption that people care only about their own material wealth. However, this assumption is clearly refuted by numerous experiments, and we feel that it may be useful to consider nonpecuniary utility in mechanism design and contract theory. Accordingly, we devise an experiment to explore optimal contracts in an adverse-selection context. A principal proposes one of three contract menus, each of which offers a choice of two incentive-compatible contracts, to two agents whose types are unknown to the principal. The agents know the set of possible menus, and choose to either accept one of the two contracts offered in the proposed menu or to reject the menu altogether; a rejection by either agent leads to lower (and equal) reservation payoffs for all parties. While all three possible menus favor the principal, they do so to varying degrees. We observe numerous rejections of the more lopsided menus, and approach an equilibrium where one of the more equitable contract menus (which one depends on the reservation payoffs) is proposed and agents accept a contract, selecting actions according to their types. Behavior is largely consistent with all recent models of social preferences, strongly suggesting there is value in considering nonpecuniary utility in agency theory.
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Similar to aboveground herbivores, root-feeding insects must locate and identify suitable resources. In the darkness of soil, they mainly rely on root chemical exudations and, therefore, have evolved specific behaviours. Because of their impact on crop yield, most of our knowledge in belowground chemical ecology is biased towards soil-dwelling insect pests. Yet the increasing literature on volatile-mediated interactions in the ground underpins the great importance of chemical signalling in this ecosystem and its potential in pest control. Here, we explore the ecology and physiology of these chemically based interactions. An evolutionary approach reveals interesting patterns in the response of insects to particular classes of volatile or water-soluble organic compounds commonly emitted by roots. Food web analyses reasonably support that volatiles are used as long-range cues whereas water-soluble molecules serve in host acceptance/rejection by the insect; however, data are still scarce. As a case study, the chemical ecology of Diabrotica virgifera virgifera is discussed and applications of belowground signalling in pest management are examined. Soil chemical ecology is an expanding field of research and will certainly be a hub of our understanding of soil communities and subsequently of the management of belowground ecosystem services.
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It has long been standard in agency theory to search for incentive-compatible mechanisms on the assumption that people care only about their own material wealth. However, this assumption is clearly refuted by numerous experiments, and we feel that it may be useful to consider nonpecuniary utility in mechanism design and contract theory. Accordingly, we devise an experiment to explore optimal contracts in an adverse-selection context. A principal proposes one of three contract menus, each of which offers a choice of two incentive-compatible contracts, to two agents whose types are unknown to the principal. The agents know the set of possible menus, and choose to either accept one of the two contracts offered in the proposed menu or to reject the menu altogether; a rejection by either agent leads to lower (and equal) reservation payoffs for all parties. While all three possible menus favor the principal, they do so to varying degrees. We observe numerous rejections of the more lopsided menus, and approach an equilibrium where one of the more equitable contract menus (which one depends on the reservation payoffs) is proposed and agents accept a contract, selecting actions according to their types. Behavior is largely consistent with all recent models of social preferences, strongly suggesting there is value in considering nonpecuniary utility in agency theory.
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CD4+CD25+ regulatory T cells (Tregs) play a critical role in the prevention of autoimmune diseases as well as in the induction and maintenance of dominant tolerance in transplantation models. While their suppressive function has been extensively studied in vitro, their homeostasis and mechanisms of immunoregulation still remain to be clarifi ed in vivo. Using a murine adoptive transfer and skin allograft model, we analysed the expansion, effector function and traffi cking of effector T cells in the presence or absence of donor-specifi c Tregs. Although hyporesponsive to allogeneic and polyclonal stimulation in vitro, transferred Tregs survived and expanded, in response to an allograft in vivo. When co-transferred with naive CD4+CD25- effector T cells, they specifi cally prevented donor but not 3rd party allograft rejection by inhibiting the production of effector cytokines rather than the proliferation of effector T cells in response to alloantigens. The co-transfer of donor-specifi c Tregs did not affect the homing of effector T cells towards the graft draining lymph nodes, but it markedly reduced the infi ltration of the allograft by these pathogenic cells. Furthermore, in recipients where donor-specifi c transplantation tolerance was induced, Tregs preferentially accumulated in the allograft draining lymph nodes and within the grafted skin itself. Taken together, our results suggest that the suppression of graft rejection is an active process that involves the persistent presence of Tregs at the site of antigenic challenge.
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To study sensitisation to minor histocompatibility antigens (mHag) before and after BMT, we measured antidonor CTL activity in five patients who had rejected their graft, and in a control group of 10 leukemic patients who engrafted without complications. All patients were transplanted with marrow from an HLA-identical sibling. Fourteen patients were conditioned with cyclophosphamide (120 mg/kg) and TBI (1350 cGy) and received a T cell-depleted graft, while one patient with aplastic anaemia received cyclophosphamide alone and unmanipulated marrow. Before transplantation, anti-donor CTL activity was detected in two of the 15 patients. These patients rejected their grafts at days 21 and 58, respectively. In the other three patients who rejected their grafts at days 41, 60 and 250, CTL activity was found only after transplantation. In contrast, no anti-donor CTLs could be detected at any time in the 10 patients who engrafted permanently. We have identified some of the mHags recognised during graft rejection by cloning and subsequent specificity analysis of the recipient CTLs. In the patient who rejected at day 41 without detectable immunisation before BMT, the response was directed against HA-1, a minor antigen known to play a role in GVHD. In the other combinations, a significant part of the CTL activity was directed against the male antigen H-Y. In the patient who rejected the marrow of her HLA-identical brother at day 250, two clones recognised H-Y, while five others recognised at least three distinct autosomal mHags. This patient had an HLA-identical sister who expressed only one autosomal mHag that had been recognised by one single T cell clone. After re-transplantation with the marrow of this second donor, the CTL activity could no longer be detected and the patient engrafted without further complications.
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Drug addiction is a multi-etiological disorder to which some individuals are more vulnerable an others. Whereas converging clinical and epidemiological studies report a peak of drug use ring adolescence, many behavioral traits characterizing teenagers have been proposed to contribute to this vulnerability, including a heightened sensation-seeking, an enhanced impulsivity d a larger influence exerted by peers. By many aspects, juvenile rodents display behavioral traits at resemble those of teenagers. However, the concept of increased vulnerability to drug addiction juvenile rats remains in debate. Indeed, only a few studies directly compared juvenile and adult fdents regarding behavioral predictors of drug abuse. Moreover, some key features of drug diction have never been investigated in juvenile rats yet. For this very reason, we conducted a arge-scale behavioral comparison of adult and adolescent rats with the aim of dissecting their espective behavioral traits and vulnerabilities to drug addiction. We first have shown that juvenile rats exhibited an enhanced motor impulsivity, and a loss of control over reward seeking assessed by a persistent reward taking despite adverse consequences mild electric footshocks]. We also report that juvenile rats displayed a higher anxiety profile, ind we discuss why these behaviors might represent key underpinning mechanisms leading to an enhanced vulnerability to drug abuse. Meanwhile, we collected clear cut observations that do not support such an interpretation. In Articular, juvenile and adult rats displayed identical novelty-induced habituation and preference at are considered to represent two potent predictors of cocaine initiation and compulsive intake, "pre strikingly, juvenile rats were less attracted by cues predicting reward in a Pavlovian utoshaping task, suggesting a lower propensity for cues or context to trigger the reinstatement of a^previously extinguished reward seeking behavior. Finally, using a paradigm assessing schedule- ciuced polydipsia, juvenile and adult rats exhibited similar compulsive drinking, under control conditions and following a chronic cocaine treatment as well. Hence, these observations call for a cautious interpretation of adolescent vulnerability to drug use. In particular, we underlined that even the most compulsive young rats did not consume ärger amounts of cocaine than adults, nor exhibited larger efforts in a cue-induced relapse aradigm, despite a transient increased motivation for lever-pressing. And further, despite a higher ensitivity to the behavioral effects of cocaine, juvenile rats did not differ from adults in their ropensity to constantly prefer saccharin over cocaine in a discrete-choice procedure, even after a ?'Id chronic stress procedure. Altogether, our results shape an objective overview of the juvenile rats' behavior in relation to oth drug and non-drug rewards, suggesting a heterogeneous and task-specific profile. Despite elements potentially underlying a real risk for substance use, adolescent rats do not exhibit a ehavioral repertoire suggesting increased vulnerability for compulsive drug abuse. Our conclusions strongly encourage deeper neurobiological investigations of the developing brain, and also open a debate on a possible overestimation of juvenile rats' and teenager's risk to develop aladaptive behaviors and drug addiction. - L'addiction aux drogues est une pathologie d'origine multifactorielle, à laquelle certains individus sont plus vulnérables que d'autres. De nombreuses études cliniques et épidémiologiques suggèrent une consommation excessive de drogues pendant l'adolescence, et plusieurs explications ont été avancées pour justifier cette tendance, parmi lesquelles on note une augmentation de la recherche de sensation, une impulsivité plus marquée et une plus forte influence de l'entourage. Le rat juvénile présente de nombreuses caractéristiques développementales similaires à l'adolescence humaine. En revanche, la vulnérabilité des rats juvéniles à l'abus de drogue est encore sujette à caution. En effet, peu d'études ont directement comparé des traits de comportements pouvant refléter un accroissement du risque d'abus chez les rats juvéniles par comparaison aux rats adultes. En outre, certaines caractéristiques fondamentales de l'addiction chez l'homme n'ont pas encore été étudiées chez le rat adolescent. Ce travail de thèse s'est donc donné pour objectif de comparer le comportement de rats adultes vis-à-vis de celui de rats adolescents, afin d'évaluer dans quelle mesure ces derniers seraient plus vulnérables à l'abus de drogues. Nos résultats indiquent que les rats juvéniles présentent une augmentation des comportements impulsifs, ainsi qu'une plus grande persistance à rechercher de manière compulsive une récompense en dépit de légers chocs électriques. Les rats juvéniles présentent également un profil anxieux plus élevé, ce qui peut constituer une autre source de vulnérabilité. Cependant, certaines caractéristiques comportementales ne suggèrent pas de vulnérabilité chez les rats juvéniles. Aucune différence entre rats adultes et adolescents n'a été trouvée pour l'habituation et la préférence pour la nouveauté, deux traits prédisant l'initiation et la prise compulsive de drogue. De plus, nous avons montré que les rats adolescents attribuent moins d'intérêt à des stimuli prédisant la disponibilité d'une récompense, suggérant une vulnérabilité plus faible à la rechute induite par les stimuli associés à la prise de drogue. Une étude complémentaire des comportements compulsifs indique une absence de différence entre rats adultes et adolescents, à la fois en condition basale ou après un traitement chronique à la cocaïne. L'étude des comportements de prise de drogue ne va pas non plus dans le sens d'une vulnérabilité des rats adolescents. Bien que les rats compulsifs sélectionnés pendant la période juvénile présentent une plus grande motivation à prendre de la cocaïne, ils ne diffèrent ni dans la quantité de cocaïne consommée, ni dans la rechute induite par les stimuli environnementaux. En dépit d'une sensibilisation comportementale plus importante, les rats adolescents présentent la même préférence que les adultes face à un choix entre une drogue et une récompense alternative, suggérant une résilience à la cocaïne comparable à celle des adultes. Enfin, cette résilience pour la cocaïne n'est pas affectée par un stress chronique lors de l'adolescence. En résumé, cette étude dresse un regard objectif sur les comportements en lien avec une vulnérabilité à l'abus de drogues chez le rat juvénile, suggérant que celle-ci est hétérogène et spécifique au protocole utilisé. En dépit de certains éléments de vulnérabilité, les rats adolescents ne présentent pas d'attirance excessive pour la cocaïne, ni de prédisposition à la consommation compulsive de cette drogue. L'ensemble de ces éléments pourra constituer une base solide pour l'investigation neurobiologique du cerveau en développement, et ouvre un débat sur une possible surestimation de la vulnérabilité des rats juvéniles et de leurs homologues humains aux pathologies psychiatriques telles que l'addiction aux drogues.