902 resultados para The modes of action
Resumo:
Objective: Compensatory health beliefs (CHBs), defined as beliefs that healthy behaviours can compensate for unhealthy behaviours, may be one possible factor hindering people in adopting a healthier lifestyle. This study examined the contribution of CHBs to the prediction of adolescents’ physical activity within the theoretical framework of the Health Action Process Approach (HAPA). Design: The study followed a prospective survey design with assessments at baseline (T1) and two weeks later (T2). Method: Questionnaire data on physical activity, HAPA variables and CHBs were obtained twice from 430 adolescents of four different Swiss schools. Multilevel modelling was applied. Results: CHBs added significantly to the prediction of intentions and change in intentions, in that higher CHBs were associated with lower intentions to be physically active at T2 and a reduction in intentions from T1 to T2. No effect of CHBs emerged for the prediction of self-reported levels of physical activity at T2 and change in physical activity from T1 to T2. Conclusion: Findings emphasise the relevance of examining CHBs in the context of an established health behaviour change model and suggest that CHBs are of particular importance in the process of intention formation.
Resumo:
The goal of the present article is to introduce dual-process theories – in particular the default-interventionist model – as an overarching framework for attention-related research in sports. Dual-process theories propose that two different types of processing guide human behavior. Type 1 processing is independent of available working memory capacity (WMC), whereas Type 2 processing depends on available working memory capacity. We review the latest theoretical developments on dual-process theories and present evidence for the validity of dual-process theories from various domains. We demonstrate how existing sport psychology findings can be integrated within the dual-process framework. We illustrate how future sport psychology research might benefit from adopting the dual-process framework as a meta-theoretical framework by arguing that the complex interplay between Type 1 and Type 2 processing has to be taken into account in order to gain a more complete understanding of the dynamic nature of attentional processing during sport performance at varying levels of expertise. Finally, we demonstrate that sport psychology applications might benefit from the dual-process perspective as well: dual-process theories are able to predict which behaviors can be more successfully executed when relying on Type 1 processing and which behaviors benefit from Type 2 processing.
Resumo:
The protection and sustainable management of alpine summer pastures has been stated as a goal in Swiss national law since 1996, and direct payments from the state for summer pasturing have been tied to sustainability criteria since 2000. This reflects the increasing value of the alpine cultural landscape as a public good. However, provision of this public good remains in the hands of local farmers and their local common pool resource (CPR) institutions for managing alpine pastures. These institutions are increasingly struggling to maintain their institutional arrangements, particularly regarding the work needed to maintain the pastures. This paper examines two cases of local CPR institutions for managing alpine pastures in the Swiss Canton of Grisons that manifest different institutional developments in light of changing conditions. The differences in how these institutions reacted to change and the impacts this has had on the provision of the CPR are explained by focusing on relative prices, bargaining power, and ideology as drivers of institutional change that are often neglected within common property research. Key words: summer pasture management, institutional change, bargaining power, ideology
Resumo:
In epithelial/endothelial barriers, claudins form tight junctions, seal the paracellular cleft, and limit the uptake of solutes and drugs. The peptidomimetic C1C2 from the C-terminal half of claudin-1's first extracellular loop increases drug delivery through epithelial claudin-1 barriers. However, its molecular and structural mode of action remains unknown. In the present study, >100 μM C1C2 caused paracellular opening of various barriers with different claudin compositions, ranging from epithelial to endothelial cells, preferentially modulating claudin-1 and claudin-5. After 6 h incubation, C1C2 reversibly increased the permeability to molecules of different sizes; this was accompanied by redistribution of claudins and occludin from junctions to cytosol. Internalization of C1C2 in epithelial cells depended on claudin-1 expression and clathrin pathway, whereby most C1C2 was retained in recyclosomes >2 h. In freeze-fracture electron microscopy, C1C2 changed claudin-1 tight junction strands to a more parallel arrangement and claudin-5 strands from E-face to P-face association - drastic and novel effects. In conclusion, C1C2 is largely recycled in the presence of a claudin, which explains the delayed onset of barrier and junction loss, the high peptide concentration required and the long-lasting effect. Epithelial/endothelial barriers are specifically modulated via claudin-1/claudin-5, which can be targeted to improve drug delivery.
Resumo:
The purpose of this study was to determine the effects of benzodiazepine in area CA1 of the hippocampus, and to explore possible mechanisms of action for these agents in this brain area. Two distinctly different benzodiazepine-induced changes in hippocampal physiology have been identified. First, benzodiazepine depresses the population spike recorded in stratum pyramidale, indicating a decrease in action potential generation. Second, benzodiazepine decreases the magnitude of post-tetanic potentiation of the population EPSP recorded in stratum radiatum, and shortens the duration. The effect of benzodiazepine on pyramidal cell excitation was reversed by the GABA antagonis bicuculline, and mimicked by GABA itself. Thus the available evidence is consistent with the hypothesis that benzodiazepine acts by enhancing the effect of GABA in this area. In stratum radiatum, on the other hand, the effect of benzodiazepine on post tetanic potentiation of the population EPSP was not altered by bicuculline although bicuculline did antagonize GABA in this area. In addition, application of GABA, while it caused profound changes in the population EPSP,p, did not cause the same changes that were induced by benzodiazepine. Thus the evidence does not support the hypothesis that benzodiazepine is acting in stratum radiatum by enhancing the effects of GABA. ^
Resumo:
Previous studies have led to the development of allochimeric class I MHC proteins as agents that effectively induce donor-specific transplantation tolerance in a rat system with or without additional immunosuppression. Within the α1-helical region of RT1.Au, an epitope that conferred immunologic tolerance was discovered. Studies presented herein were designed to test our central hypothesis that allochimeric proteins onfer tolerance in a mouse model. To test this hypothesis, portal vein (PV) injection of wild-type H2Kd and H2Dd proteins were produced in a bacterial expression system and found to specifically prolong the survival of BALB/c (H2d) heart allografts in C57BL/10 (H2b) recipients. Although a single PV injection of 50 μg α1–α 3 H2Kd alone was ineffective, 50 μg α1 –α3 alone slightly prolonged BALB/c heart allograft survivals. In contrast, the combination of 25 μg α1–α 3 H2Kd and 25 μg α1–α 3 H2Dd proteins prolonged BALB/c graft survivals to 20.2 ± 6.4 days (p < 0.004). The effect was donor-specific, since a combination of 25 μg α1–α3 H2Kd and 25 μg α1–α3 H2Dd proteins failed to affect survivals of third-party C3H (H2k k) heart allografts, namely 9.0 ± 0.0 days in treated versus 7.8 ± 0.5 days in untreated hosts. Thus, the combination of two H2K d and H2Dd proteins is more effective in prolonging allograft survival than a single protein produced in a bacterial expression system. A single PV injection (day 0) of 25 μg α1–α 2 H2Kd and 25 μg α1–α 2 H2Dd proteins to C57BL/10 mice prolonged the survival of BALB/c heart allografts to 22.4 ± 4.5 days. Within a WF to ACI rat heart allograft system, a single PV injection of 20 μg 70–77 u-RT1.Aa induced specific tolerance of allografts. This therapy could be combined with CsA to induce transplantation tolerance. However, combination of 70–77u-RT1.Aa with CTLA4Ig, rapamycin, or AG-490 effectively blocked the induction of transplantation tolerance. Tolerance generated by allochimeric protein could be adoptively transferred to naive recipients. Intragraft cytokine mRNA levels showed a bias towards a Th2-type phenotype. Additionally, studies of cytokine signaling and activation of transcription factors revealed a requirement that these pathways remain available for signaling in order for transplantation tolerance to occur. These studies suggest that the generation of regulatory cells are required for the induction of transplantation tolerance through the use of allochimeric proteins. ^
Implementing the Global Plan of Action on workers' health: Components to protect health care workers
Resumo:
Health care workers are at risk for percutaneous injuries and infection with blood born pathogens due to needle stick injuries with contaminated needles. The most common pathogens transmitted are hepatitis B, and C and HIV/AIDS. According to the WHO Global Plan of Action (GPA) a large gap exist between and within countries with regards to the health status of workers and their exposure to occupational risk. Less than 15% of the world's work forces have access to occupational health services despite the availability of effective interventions that can prevent occupational hazards, or protect and promote health in the workplace. The 2006 World Health Report declared that there is a global crisis in the health care work force. 1 in 400 of the world's health care workers work in Sub-Saharan Africa. 1 in 3 work in the U.S or Canada. The shortage of health care workers is worst in Southeast Asia and Sub-Saharan Africa. These countries have the highest burden of exposure to contaminated sharps. They rarely, if ever monitor the exposure or health impact of occupational ailments and injuries on workers. Many injuries are unreported. Occupational health services in the developing world are virtually non existent. Many health care workers leave their home countries and go to work in other countries where the working conditions, occupational services included, are better. The inability of countries to provide the necessary numbers of health care workers to provide a high level of health coverage is a threat to national and international public health security. Immunizing health care workers against hepatitis B and providing them PEP, PPE, education and safety training is an essential part of increasing and maintaining the numbers of health care workers in the critical shortage areas. ^
Resumo:
Nostromo. A Tale of the Seaboard (1904), una de las novelas más experimentales del período modernista temprano, ha sido considerada la obra maestra de Joseph Conrad y su más grande lienzo. Un rasgo particular de la novela es que en ella coexisten la experimentación técnica del modernismo, la altamente difusa ficción del narrador y la situación de narración de historias y el paradigma narrativo de los subgéneros "degradados" de la novela de aventuras, el romance y el melodrama. Este estudio indaga las relaciones que se establecen entre dichos elementos, a todas luces anacrónicos o pertenecientes a espacios culturales diferentes, y se propone mostrar que estas discontinuidades no deben ser consideradas una falla sino índices de una tensión constitutiva de la novela.
Resumo:
Nostromo. A Tale of the Seaboard (1904), una de las novelas más experimentales del período modernista temprano, ha sido considerada la obra maestra de Joseph Conrad y su más grande lienzo. Un rasgo particular de la novela es que en ella coexisten la experimentación técnica del modernismo, la altamente difusa ficción del narrador y la situación de narración de historias y el paradigma narrativo de los subgéneros "degradados" de la novela de aventuras, el romance y el melodrama. Este estudio indaga las relaciones que se establecen entre dichos elementos, a todas luces anacrónicos o pertenecientes a espacios culturales diferentes, y se propone mostrar que estas discontinuidades no deben ser consideradas una falla sino índices de una tensión constitutiva de la novela.
Resumo:
Nostromo. A Tale of the Seaboard (1904), una de las novelas más experimentales del período modernista temprano, ha sido considerada la obra maestra de Joseph Conrad y su más grande lienzo. Un rasgo particular de la novela es que en ella coexisten la experimentación técnica del modernismo, la altamente difusa ficción del narrador y la situación de narración de historias y el paradigma narrativo de los subgéneros "degradados" de la novela de aventuras, el romance y el melodrama. Este estudio indaga las relaciones que se establecen entre dichos elementos, a todas luces anacrónicos o pertenecientes a espacios culturales diferentes, y se propone mostrar que estas discontinuidades no deben ser consideradas una falla sino índices de una tensión constitutiva de la novela.
Resumo:
Nostromo. A Tale of the Seaboard (1904), una de las novelas más experimentales del período modernista temprano, ha sido considerada la obra maestra de Joseph Conrad y su más grande lienzo. Un rasgo particular de la novela es que en ella coexisten la experimentación técnica del modernismo, la altamente difusa ficción del narrador y la situación de narración de historias y el paradigma narrativo de los subgéneros "degradados" de la novela de aventuras, el romance y el melodrama. Este estudio indaga las relaciones que se establecen entre dichos elementos, a todas luces anacrónicos o pertenecientes a espacios culturales diferentes, y se propone mostrar que estas discontinuidades no deben ser consideradas una falla sino índices de una tensión constitutiva de la novela.
Resumo:
Understanding the impact of ocean acidification and warming on communities and ecosystems is a researcher priority. This can only be achieved through a combination of experimental and field approaches that would allow developing a mechanistic understanding of impacts across level of biological organizations. Surprisingly, most published studies are still focusing on single species responses with little consideration for interspecific interactions. In this study, the impacts of a 3 days exposure to three parameters (temperature, pH, and presence/absence of the predator cue of the crab Charybdis japonica) and their interactions on an ecologically important endpoint were evaluated: the byssus production of the mussel Mytilus coruscus. Tested temperatures (25°C and 30°C) were within the present range of natural variability whereas pH (8.1, 7.7, and 7.4) covered present as well as near-future natural variability. As expected, the presence of the crab cue induced an antipredator response in Mytilus coruscus (significant 10% increase in byssus secretion rate, 22% increase in frequency of shed byssus, and 30% longer byssus). Decreased pH but not temperature had a significant negative impact on the same endpoints (up to a 17% decrease in byssus secretion rate, 40% decrease in frequency of shed byssus, and 10% shorter byssus at pH 7.3 as compared with pH 8.1) with no significant interactions between the three tested parameters. In this study, it has been hypothesized that pH and predator cue have different modes of action and lead to conflicting functional responses (escape response versus stronger attachment). Functional consequences for ecosystem dynamics still need to be investigated.