836 resultados para 750902 Understanding the pasts of other societies


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OBJECTIVE: This study aimed to use qualitative methodology to understand the current role of community pharmacists in limiting the use of antipsychotics prescribed inappropriately for behavioural and psychological symptoms of dementia. DESIGN: A qualitative study employing focus groups was conducted. Data were analysed using thematic analysis. SETTING: 3 different geographical locations in the England. PARTICIPANTS: Community pharmacists (n=22). RESULTS: The focus groups identified an array of factors and constraints, which affect the ability of community pharmacists to contribute to initiatives to limit the use of antipsychotics. 3 key themes were revealed: (1) politics and the medical hierarchy, which created communication barriers; (2) how resources and remit impact the effectiveness of community pharmacy; and (3) understanding the nature of the treatment of dementia. CONCLUSIONS: Our findings suggest that an improvement in communication between community pharmacists and healthcare professionals, especially general practitioners (GPs) must occur in order for community pharmacists to assist in limiting the use of antipsychotics in people with dementia. Additionally, extra training in working with people with dementia is required. Thus, an intervention which involves appropriately trained pharmacists working in collaboration with GPs and other caregivers is required. Overall, within the current environment, community pharmacists question the extent to which they can contribute in helping to reduce the prescription of antipsychotics.

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Research with adult samples has identified a cognitive risk factor for the development of panic and other anxiety disorders in the concept of anxiety sensitivity. The research to date on anxiety sensitivity in children, using the Childhood Anxiety Sensitivity Index (CASI), suggests that the CASI may help to garner knowledge regarding the development of anxiety sensitivity and also help to understand the development of panic attacks, panic disorder and other anxiety disorders in youth. To examine the development of anxiety sensitivity and its relation to panic in youth, data were collected on 44 children in 1998 who were administered the CASI in 1991. Results indicated that children whose CASI scores increased from Time 1 to Time 2 were significantly more likely to report experiencing panic attacks than children whose CASI scores decreased from Time 1 to Time 2. Specifically, 64% (9/14) of children whose CASI scores increased from Time 1 to Time 2 reported having one or more panic attacks versus 36% (5/14) reported having none. Moreover, 72% (21/29) of children whose CASI scores decreased from Time 1 to Time 2 reported no panic attacks. These results suggest that childhood may be the time when anxiety sensitivity as a risk factor for panic and panic disorder is developing. Results are discussed in terms of their relevance for understanding the development of panic and the need for further research to determine the generalizability of these findings in larger samples of children followed over different time spans. ^

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Organizations are becoming increasingly diverse as a growing number of women and ethnic minorities enter the workforce. Understanding the influence of diversity is particularly important for organizations that rely on team-based work structures, where individuals must engage in face-to-face interactions more frequently than in other organizational settings. The purpose of this research was to examine the effects of gender and ethnic diversity on team member interactions when performing a highly interdependent task that is both cognitively and behaviorally challenging. Participants were composed of 264 undergraduate students who enrolled in psychology courses at Florida International University and formed 66, 4-person teams. Teams participated in a low fidelity F-22 flight simulation consisting of two aircraft that had to interact in order to be successful. A 2 x 2 design was utilized in which the gender and ethnicity composition of each team was manipulated to form four experimental conditions (same gender/same ethnicity, same gender/mixed ethnicity, mixed gender/same ethnicity, mixed gender/mixed ethnicity). Both ethnic and gender homogeneity in teams resulted in increased interpersonal cohesion. Moreover, coordination fully mediated the relationship between interpersonal cohesion and team performance. Higher levels of interpersonal cohesion enhanced coordination between team members, which ultimately improved performance. Implications of these findings are discussed, as are limitations of the study and suggestions for future research. ^

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Background: Interventions to increase cooking skills (CS) and food skills (FS) as a route to improving overall diet are popular within public health. This study tested a comprehensive model of diet quality by assessing the influence of socio-demographic, knowledge- and psychological-related variables alongside perceived CS and FS abilities. The correspondence of two measures of diet quality further validated the Eating Choices Index (ECI) for use in quantitative research.
Methods: A cross-sectional survey was conducted in a quota-controlled nationally representative sample of 1049 adults aged 20–60 years drawn from the Island of Ireland. Surveys were administered in participants’ homes via computer-assisted personal interviewing (CAPI) assessing a range of socio-demographic, knowledge- and psychological-related variables alongside perceived CS and FS abilities. Regression models were used to model factors influencing diet quality. Correspondence between 2 measures of diet quality was assessed using chi-square and Pearson correlations.
Results: ECI score was significantly negatively correlated with DINE Fat intake (r = -0.24, p < 0.001), and ECI score was significantly positively correlated with DINE Fibre intake (r = 0.38, p < 0.001), demonstrating a high agreement. Findings indicated that males, younger respondents and those with no/few educational qualifications scored significantly lower on both CS and FS abilities. The relative influence of socio-demographic, knowledge, psychological variables and CS and FS abilities on dietary outcomes varied, with regression models explaining 10–20 % of diet quality variance. CS ability exerted the strongest relationship with saturated fat intake (β = -0.296, p < 0.001) and was a significant predictor of fibre intake (β = -0.113, p < 0.05), although not for healthy food choices (ECI) (β = 0.04, p > 0.05).
Conclusion: Greater CS and FS abilities may not lead directly to healthier dietary choices given the myriad of other factors implicated; however, CS appear to have differential influences on aspects of the diet, most notably in relation to lowering saturated fat intake. Findings suggest that CS and FS should not be singular targets of interventions designed to improve diet; but targeting specific sub-groups of the population e.g. males, younger adults, those with limited education might be more fruitful. A greater understanding of the interaction of factors influencing cooking and food practices within the home is needed.

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Thesis (Ph.D.)--University of Washington, 2016-08

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Introduction: In Nepal, by tradition, family life and marriage are generally controlled by patriarchal norms, sanctions, values and gender differences. Women in Nepal have limited possibilities to make decisions regarding their sexual and reproductive health, as the husbands and other elders in the family make most of the decisions regarding family planning, pregnancy and childbirth. Aim: To describe the perceptions of Nepali men regarding the role of the man with respect to family planning, pregnancy and childbirth. Methods: A qualitative study was conducted with 15 Nepali men in both urban and rural areas. The material was analyzed through inductive content analysis. Findings: One main category and two generic categories were identified. One generic category contained six subcategories and the other five subcategories. The main category was labeled: “He leads – She follows” and the generic categories were labeled: “Supporting women in family planning, during pregnancy and childbirth” and “Withdrawal from supporting women in family planning, during pregnancy and childbirth”. Conclusion: The role of the Nepali men with respect to family planning, pregnancy and childbirth, was identified as a conflicted approach. This study highlights the importance of understanding the influence of culture and tradition when developing strategies for promoting sexual and reproductive health during family planning, pregnancy and childbirth among families in Nepal.

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Partnership is a dominant theme in education policy and practice in England and in other western countries but remains relatively under-researched, especially with respect to what sustains a partnership. This article draws on a study of partnership working in the field of post-16 learning that revealed the role of dimensions of social capital in supporting and sustaining the case study partnership. The research adopted a grounded approach and used multiple methods of data gathering including observations of partnership meetings, semi-structured interviews and documentary research. The findings reported here focus on aspects of partnership working and facets of social capital that support and sustain partnership, including multiple layers of collaboration, networks and networking, high levels of trust and shared norms and values amongst key participants. The analysis suggests that the contested concept of social capital provides a useful theoretical frame for understanding the basis of sustainability in education partnerships.

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The aim of this thesis was to examine the role of environmental sustainability in the procurement of medical devices in health care sector. Current literature is mainly focused on other product groups and medical devices have been left without sufficient attention. Nevertheless, EU has recently developed green public procurement criteria for medical devices (EU GPP criteria for health care EEE) in order to support and offer guidelines for purchasers in hospitals. In this study, the criteria were used as a framework in order to examine the most significant environmental aspects for medical devices. The empirical research was executed in Finnish public hospitals with mixed method approach; quantitative data was collected by a survey and qualitative data was collected by interviews held for procurement specialists. The focus was on understanding the importance of environmental sustainability in the procurement of medical devices and which environmentally sustainable features would be the most significant. Of interest was also the medical device supplier view and how they could take environmental sustainability into consideration.

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Membrane proteins, which reside in the membranes of cells, play a critical role in many important biological processes including cellular signaling, immune response, and material and energy transduction. Because of their key role in maintaining the environment within cells and facilitating intercellular interactions, understanding the function of these proteins is of tremendous medical and biochemical significance. Indeed, the malfunction of membrane proteins has been linked to numerous diseases including diabetes, cirrhosis of the liver, cystic fibrosis, cancer, Alzheimer's disease, hypertension, epilepsy, cataracts, tubulopathy, leukodystrophy, Leigh syndrome, anemia, sensorineural deafness, and hypertrophic cardiomyopathy.1-3 However, the structure of many of these proteins and the changes in their structure that lead to disease-related malfunctions are not well understood. Additionally, at least 60% of the pharmaceuticals currently available are thought to target membrane proteins, despite the fact that their exact mode of operation is not known.4-6 Developing a detailed understanding of the function of a protein is achieved by coupling biochemical experiments with knowledge of the structure of the protein. Currently the most common method for obtaining three-dimensional structure information is X-ray crystallography. However, no a priori methods are currently available to predict crystallization conditions for a given protein.7-14 This limitation is currently overcome by screening a large number of possible combinations of precipitants, buffer, salt, and pH conditions to identify conditions that are conducive to crystal nucleation and growth.7,9,11,15-24 Unfortunately, these screening efforts are often limited by difficulties associated with quantity and purity of available protein samples. While the two most significant bottlenecks for protein structure determination in general are the (i) obtaining sufficient quantities of high quality protein samples and (ii) growing high quality protein crystals that are suitable for X-ray structure determination,7,20,21,23,25-47 membrane proteins present additional challenges. For crystallization it is necessary to extract the membrane proteins from the cellular membrane. However, this process often leads to denaturation. In fact, membrane proteins have proven to be so difficult to crystallize that of the more than 66,000 structures deposited in the Protein Data Bank,48 less than 1% are for membrane proteins, with even fewer present at high resolution (< 2Å)4,6,49 and only a handful are human membrane proteins.49 A variety of strategies including detergent solubilization50-53 and the use of artificial membrane-like environments have been developed to circumvent this challenge.43,53-55 In recent years, the use of a lipidic mesophase as a medium for crystallizing membrane proteins has been demonstrated to increase success for a wide range of membrane proteins, including human receptor proteins.54,56-62 This in meso method for membrane protein crystallization, however, is still by no means routine due to challenges related to sample preparation at sub-microliter volumes and to crystal harvesting and X-ray data collection. This dissertation presents various aspects of the development of a microfluidic platform to enable high throughput in meso membrane protein crystallization at a level beyond the capabilities of current technologies. Microfluidic platforms for protein crystallization and other lab-on-a-chip applications have been well demonstrated.9,63-66 These integrated chips provide fine control over transport phenomena and the ability to perform high throughput analyses via highly integrated fluid networks. However, the development of microfluidic platforms for in meso protein crystallization required the development of strategies to cope with extremely viscous and non-Newtonian fluids. A theoretical treatment of highly viscous fluids in microfluidic devices is presented in Chapter 3, followed by the application of these strategies for the development of a microfluidic mixer capable of preparing a mesophase sample for in meso crystallization at a scale of less than 20 nL in Chapter 4. This approach was validated with the successful on chip in meso crystallization of the membrane protein bacteriorhodopsin. In summary, this is the first report of a microfluidic platform capable of performing in meso crystallization on-chip, representing a 1000x reduction in the scale at which mesophase trials can be prepared. Once protein crystals have formed, they are typically harvested from the droplet they were grown in and mounted for crystallographic analysis. Despite the high throughput automation present in nearly all other aspects of protein structure determination, the harvesting and mounting of crystals is still largely a manual process. Furthermore, during mounting the fragile protein crystals can potentially be damaged, both from physical and environmental shock. To circumvent these challenges an X-ray transparent microfluidic device architecture was developed to couple the benefits of scale, integration, and precise fluid control with the ability to perform in situ X-ray analysis (Chapter 5). This approach was validated successfully by crystallization and subsequent on-chip analysis of the soluble proteins lysozyme, thaumatin, and ribonuclease A and will be extended to microfluidic platforms for in meso membrane protein crystallization. The ability to perform in situ X-ray analysis was shown to provide extremely high quality diffraction data, in part as a result of not being affected by damage due to physical handling of the crystals. As part of the work described in this thesis, a variety of data collection strategies for in situ data analysis were also tested, including merging of small slices of data from a large number of crystals grown on a single chip, to allow for diffraction analysis at biologically relevant temperatures. While such strategies have been applied previously,57,59,61,67 they are potentially challenging when applied via traditional methods due to the need to grow and then mount a large number of crystals with minimal crystal-to-crystal variability. The integrated nature of microfluidic platforms easily enables the generation of a large number of reproducible crystallization trials. This, coupled with in situ analysis capabilities has the potential of being able to acquire high resolution structural data of proteins at biologically relevant conditions for which only small crystals, or crystals which are adversely affected by standard cryocooling techniques, could be obtained (Chapters 5 and 6). While the main focus of protein crystallography is to obtain three-dimensional protein structures, the results of typical experiments provide only a static picture of the protein. The use of polychromatic or Laue X-ray diffraction methods enables the collection of time resolved structural information. These experiments are very sensitive to crystal quality, however, and often suffer from severe radiation damage due to the intense polychromatic X-ray beams. Here, as before, the ability to perform in situ X-ray analysis on many small protein crystals within a microfluidic crystallization platform has the potential to overcome these challenges. An automated method for collecting a "single-shot" of data from a large number of crystals was developed in collaboration with the BioCARS team at the Advanced Photon Source at Argonne National Laboratory (Chapter 6). The work described in this thesis shows that, even more so than for traditional structure determination efforts, the ability to grow and analyze a large number of high quality crystals is critical to enable time resolved structural studies of novel proteins. In addition to enabling X-ray crystallography experiments, the development of X-ray transparent microfluidic platforms also has tremendous potential to answer other scientific questions, such as unraveling the mechanism of in meso crystallization. For instance, the lipidic mesophases utilized during in meso membrane protein crystallization can be characterized by small angle X-ray diffraction analysis. Coupling in situ analysis with microfluidic platforms capable of preparing these difficult mesophase samples at very small volumes has tremendous potential to enable the high throughput analysis of these systems on a scale that is not reasonably achievable using conventional sample preparation strategies (Chapter 7). In collaboration with the LS-CAT team at the Advanced Photon Source, an experimental station for small angle X-ray analysis coupled with the high quality visualization capabilities needed to target specific microfluidic samples on a highly integrated chip is under development. Characterizing the phase behavior of these mesophase systems and the effects of various additives present in crystallization trials is key for developing an understanding of how in meso crystallization occurs. A long term goal of these studies is to enable the rational design of in meso crystallization experiments so as to avoid or limit the need for high throughput screening efforts. In summary, this thesis describes the development of microfluidic platforms for protein crystallization with in situ analysis capabilities. Coupling the ability to perform in situ analysis with the small scale, fine control, and the high throughput nature of microfluidic platforms has tremendous potential to enable a new generation of crystallographic studies and facilitate the structure determination of important biological targets. The development of platforms for in meso membrane protein crystallization is particularly significant because they enable the preparation of highly viscous mixtures at a previously unachievable scale. Work in these areas is ongoing and has tremendous potential to improve not only current the methods of protein crystallization and crystallography, but also to enhance our knowledge of the structure and function of proteins which could have a significant scientific and medical impact on society as a whole. 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Low-molecular-weight fucoidan (LMWF) is a sulfated polysaccharide extracted from brown seaweed that presents antithrombotic and pro-angiogenic properties. However, its mechanism of action is not well-characterized. Here, we studied the effects of LMWF on cell signaling and whole genome expression in human umbilical vein endothelial cells and endothelial colony forming cells. We observed that LMWF and vascular endothelial growth factor had synergistic effects on cell signaling, and more interestingly that LMWF by itself, in the absence of other growth factors, was able to trigger the activation of the PI3K/AKT pathway, which plays a crucial role in angiogenesis and vasculogenesis. We also observed that the effects of LMWF on cell migration were PI3K/AKT-dependent and that LMWF modulated the expression of genes involved at different levels of the neovessel formation process, such as cell migration and cytoskeleton organization, cell mobilization and homing. This provides a better understanding of LMWF's mechanism of action and confirms that it could be an interesting therapeutic approach for vascular repair.

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Poster presented at the 22nd International HIV Dynamics and Evolution. Budapest, Hungary, 13-16 May 2015

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Ce mémoire porte sur le rôle des cercles abolitionnistes dans l’application des lois sur l’émancipation graduelle de l’esclavage dans le nord des États-Unis vers la fin du dix-huitième siècle, principalement à New York et en Pennsylvanie. Plus particulièrement, il met en lumière la façon dont ces cercles, dont les deux plus importants étaient la Pennsylvania Abolition So-ciety (PAS) et le New­York Manumission Society (NYMS), ont fait face aux centaines de réfugiés de Saint-Domingue qui sont arrivés avec leurs esclaves sur la côte est américaine pour fuir la révolution haïtienne dans les années 1790. Dans un premier temps, ce mémoire étudie l’abolition graduelle de l’esclavage dans le nord des États-Unis, débutant avec la Pennsylvanie en 1780, et la formation des cercles abolitionnistes dans les anciennes colonies anglaises. Il sera en outre question des stratégies des antiesclavagistes américains afin de promouvoir l’abolition graduelle de l’esclavage et d’empêcher le mouvement des esclaves et des noirs libres en dehors des frontières de leurs États respectifs. Il sera aussi question de leurs efforts pour resserrer davantage les clauses des lois existantes à ce sujet. Dans un second temps, dans le but de mettre en relief la contribution des cercles abolitionnistes, ce mémoire procède à une étude de cas sur la manière dont les réfugiés de Saint-Domingue ont interagi avec l’esclavage résiduel à New York et en Pennsylvanie et cherche à comprendre pourquoi leurs tentatives d’échapper aux lois sur l’émancipation graduelle se sont heurtées, à plusieurs reprises, aux stratégies des sociétés antiesclavagistes.

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The purpose of my thesis was to explore the problem surrounding the sources believed to constitute the Ur-Hamlet from which Shakespeare derived Hamlet. By utilization of close reading, analysis, and archetypical criticism, my thesis confirms Shakespeare’s usage of the “Hero as Fool” archetype present in the Danish legend of Amleth, translated by Saxo Grammaticus and Francois Belleforest, as the Ur-Hamlet. My study is significant because it further develops the notion that the earlier legend served as the originary source for Hamlet, while providing evidence that rejects the validity of other sources of the Ur-Hamlet. The evidence was corroborated by presenting analytical comparisons of the framework both works share. Focusing on the archetypal origins of Shakespeare’s plot, characters and their actions revealed a more complex understanding of the play. These findings indicate and substantiate the claim that the Ur-Hamlet can be no other source but the Danish legend of Amleth.

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Ce mémoire porte sur le rôle des cercles abolitionnistes dans l’application des lois sur l’émancipation graduelle de l’esclavage dans le nord des États-Unis vers la fin du dix-huitième siècle, principalement à New York et en Pennsylvanie. Plus particulièrement, il met en lumière la façon dont ces cercles, dont les deux plus importants étaient la Pennsylvania Abolition So-ciety (PAS) et le New­York Manumission Society (NYMS), ont fait face aux centaines de réfugiés de Saint-Domingue qui sont arrivés avec leurs esclaves sur la côte est américaine pour fuir la révolution haïtienne dans les années 1790. Dans un premier temps, ce mémoire étudie l’abolition graduelle de l’esclavage dans le nord des États-Unis, débutant avec la Pennsylvanie en 1780, et la formation des cercles abolitionnistes dans les anciennes colonies anglaises. Il sera en outre question des stratégies des antiesclavagistes américains afin de promouvoir l’abolition graduelle de l’esclavage et d’empêcher le mouvement des esclaves et des noirs libres en dehors des frontières de leurs États respectifs. Il sera aussi question de leurs efforts pour resserrer davantage les clauses des lois existantes à ce sujet. Dans un second temps, dans le but de mettre en relief la contribution des cercles abolitionnistes, ce mémoire procède à une étude de cas sur la manière dont les réfugiés de Saint-Domingue ont interagi avec l’esclavage résiduel à New York et en Pennsylvanie et cherche à comprendre pourquoi leurs tentatives d’échapper aux lois sur l’émancipation graduelle se sont heurtées, à plusieurs reprises, aux stratégies des sociétés antiesclavagistes.

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Allostery is a phenomenon of fundamental importance in biology, allowing regulation of function and dynamic adaptability of enzymes and proteins. Despite the allosteric effect was first observed more than a century ago allostery remains a biophysical enigma, defined as the “second secret of life”. The challenge is mainly associated to the rather complex nature of the allosteric mechanisms, which manifests itself as the alteration of the biological function of a protein/enzyme (e.g. ligand/substrate binding at the active site) by binding ofother object” (“allos stereos” in Greek) at a site distant (> 1 nanometer) from the active site, namely the effector site. Thus, at the heart of allostery there is signal propagation from the effector to the active site through a dense protein matrix, with a fundamental challenge being represented by the elucidation of the physico-chemical interactions between amino acid residues allowing communicatio n between the two binding sites, i.e. the “allosteric pathways”. Here, we propose a multidisciplinary approach based on a combination of computational chemistry, involving molecular dynamics simulations of protein motions, (bio)physical analysis of allosteric systems, including multiple sequence alignments of known allosteric systems, and mathematical tools based on graph theory and machine learning that can greatly help understanding the complexity of dynamical interactions involved in the different allosteric systems. The project aims at developing robust and fast tools to identify unknown allosteric pathways. The characterization and predictions of such allosteric spots could elucidate and fully exploit the power of allosteric modulation in enzymes and DNA-protein complexes, with great potential applications in enzyme engineering and drug discovery.