950 resultados para facilitate
Resumo:
Hybrid speciation is constrained by the homogenizing effects of gene flow from the parental species. In the absence of post-mating isolation due to structural changes in the genome, or temporal or spatial premating isolation, another form of reproductive isolation would be needed for homoploid hybrid speciation to occur. Here, we investigate the potential of behavioural mate choice to generate assortative mating among hybrids and parental species. We made three-first-generation hybrid crosses between different species of African cichlid fish. In three-way mate-choice experiments, we allowed hybrid and nonhybrid females to mate with either hybrid or nonhybrid males. We found that hybrids generally mated nonrandomly and that hybridization can lead to the expression of new combinations of traits and preferences that behaviourally isolate hybrids from both parental species. Specifically, we find that the phenotypic distinctiveness of hybrids predicts the symmetry and extent of their reproductive isolation. Our data suggest that behavioural mate choice among hybrids may facilitate the establishment of isolated hybrid populations, even in proximity to one or both parental species.
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Distrust should automatically activate a "thinking the opposite". Thus, according to Schul, Mayo and Burnstein (2004), subjects detect antonyms of adjectives faster when confronted with untrustworthy rather than trustworthy faces. We conducted four experiments within their paradigm to test whether the response latency of detecting antonyms remains stable. We introduced the following changes: the paradigm was applied with and without an induction phase, faces were culturally adapted, the stimuli were presented according more to priming rules, and the canonicity of antonyms was controlled. Results show that the response latency of detecting antonyms is difficult to predict. Even if faces are culturally adapted and priming rules are applied more strictly, response latency depends on whether the induction phase is applied and on the canonicity of antonyms rather than on the trustworthiness of faces. In general, this paradigm seems not to be appropriate to test thinking the opposite under distrust.
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Expressing emotions has social functions; it provides information, affects social interactions, and shapes relationships with others. Expressing positive emotions could be a strategic tool for improving goal attainment during social interactions at work. Such effects have been found in research on social contagion, impression management, and emotion work. However, expressing emotions one does not feel entails the risk of being perceived as inauthentic. This risk may well be worth taking when the emotions felt are negative, as expressing negative emotions usually has negative effects. When experiencing positive emotions, however, expressing them authentically promises benefits, and the advantage of amplifying them is not so obvious. We postulated that expressing, and amplifying, positive emotions would foster goal attainment in social interactions at work, particularly when dealing with superiors. Analyses are based on 494 interactions involving the pursuit of a goal by 113 employes. Multilevel analyses, including polynomial analyses, show that authentic display of positive emotions supported goal attainment throughout. However, amplifying felt positive emotions promoted goal attainment only in interactions with superiors, but not with colleagues. Results are discussed with regard to the importance of hierarchy for detecting, and interpreting, signs of strategic display of positive emotions.
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The possibility that disruptive sexual selection alone can cause sympatric speciation is currently a subject of much debate. The initial difficulty for new and rare ornament phenotypes to invade a population, and the stabilisation of the resulting polymorphism in trait and preference make this hypothesis problematic. Recent theoretical work indicates that the invasion is facilitated if males with the new phenotype have an initial advantage in male-male competition. We studied a pair of sympatric incipient species of cichlids from Lake Victoria, in which the red (Pundamilia nyererei) and blue males (P. pundamilia) vigorously defend territories. Other studies suggested that red phenotypes may have repeatedly invaded blue populations in independent episodes of speciation. We hypothesised that red coloration confers an advantage in male-male competition, assisting red phenotypes to invade. To test this hypothesis, we staged contests between red and blue males from a population where the phenotypes are interbreeding morphs or incipient species. We staged contests under both white and green light condition. Green light effectively masks the difference between red and blue coloration. Red males dominated blue males under white light, but their competitive advantage was significantly diminished under green light. Contests were shorter when colour differences were visible. Experience of blue males with red males did not affect the outcome of a contest. The advantage of red over blue in combats may assist the red phenotype to invade blue populations. The apparently stable co-existence of red and blue incipient species in many populations of Lake Victoria cichlids is discussed.
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Dendritic cells (DCs) and macrophages populate the intestinal lamina propria to initiate immune responses required for the maintenance of intestinal homeostasis. To investigate whether CX3CR1(+) phagocytes communicate with CD4 T cells during the development of transfer colitis, we established an antigen-driven colitis model induced by the adoptive transfer of DsRed OT-II cells in CX3CR1(GFP/+) × RAG(-/-) recipients challenged with Escherichia coli expressing ovalbumin (OVA) fused to a cyan fluorescent protein (CFP). After colonization of CX3CR1(GFP/+) × RAG(-/-) animals with red fluorescent E. coli pCherry-OVA, colonic CX3CR1(+) cells but not CD103(+) DCs phagocytosed E. coli pCherry-OVA. Degraded bacterial-derived antigens are transported by CD103(+) DCs to mesenteric lymph nodes (MLNs), where CD103(+) DCs prime naive T cells. In RAG(-/-) recipients reconstituted with OT II cells and gavaged with OVA-expressing E. coli, colonic CX3CR1(+) phagocytes are in close contact with CD4 T cells and presented bacterial-derived antigens to CD4 T cells to activate and expand effector T cells.
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BACKGROUND Cardiac events (CEs) are among the most serious late effects following childhood cancer treatment. To establish accurate risk estimates for the occurrence of CEs it is essential that they are graded in a valid and consistent manner, especially for international studies. We therefore developed a data-extraction form and a set of flowcharts to grade CEs and tested the validity and consistency of this approach in a series of patients. METHODS The Common Terminology Criteria for Adverse Events version 3.0 and 4.0 were used to define the CEs. Forty patients were randomly selected from a cohort of 72 subjects with known CEs that had been graded by a physician for an earlier study. To establish whether the new method was valid for appropriate grading, a non-physician graded the CEs by using the new method. To evaluate consistency of the grading, the same charts were graded again by two other non-physicians, one with receiving brief introduction and one with receiving extensive training on the new method. We calculated weighted Kappa statistics to quantify inter-observer agreement. RESULTS The inter-observer agreement was 0.92 (95% CI 0.80-1.00) for validity, and 0.88 (0.79-0.98) and 0.99 (0.96-1.00) for consistency with the outcome assessors who had the brief introduction and the extensive training, respectively. CONCLUSIONS The newly developed standardized method to grade CEs using data from medical records has shown excellent validity and consistency. The study showed that the method can be correctly applied by researchers without a medical background, provided that they receive adequate training.
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One of the major challenges in prostate cancer (PCa) research is the identification of key players that control the progression of primary cancers to invasive and metastatic disease. The majority of metastatic PCa express wild-type p53, whereas loss of p63 expression, a p53 family member, is a common event. Here we identify inhibitor of apoptosis-stimulating protein of p53 (iASPP), a common cellular regulator of p53 and p63, as an important player of PCa progression. Detailed analysis of the prostate epithelium of iASPP transgenic mice, iASPP(Δ8/Δ8) mice, revealed that iASPP deficiency resulted in a reduction in the number of p63 expressing basal epithelial cells compared with that seen in wild-type mice. Nuclear and cytoplasmic iASPP expression was greater in PCa samples compared with benign epithelium. Importantly nuclear iASPP associated with p53 accumulation in vitro and in vivo. A pair of isogenic primary and metastatic PCa cell lines revealed that nuclear iASPP is enriched in the highly metastatic PCa cells. Nuclear iASPP is often detected in PCa cells located at the invasive leading edge in vivo. Increased iASPP expression associated with metastatic disease and PCa-specific death in a clinical cohort with long-term follow-up. These results suggest that iASPP function is required to maintain the expression of p63 in normal basal prostate epithelium, and nuclear iASPP may inactivate p53 function and facilitate PCa progression. Thus iASPP expression may act as a predictive marker of PCa progression.
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BACKGROUND Among other mismatches between human and pig, incompatibilities in the blood coagulation systems hamper the xenotransplantation of vascularized organs. The provision of the porcine endothelium with human thrombomodulin (hTM) is hypothesized to overcome the impaired activation of protein C by a heterodimer consisting of human thrombin and porcine TM. METHODS We evaluated regulatory regions of the THBD gene, optimized vectors for transgene expression, and generated hTM expressing pigs by somatic cell nuclear transfer. Genetically modified pigs were characterized at the molecular, cellular, histological, and physiological levels. RESULTS A 7.6-kb fragment containing the entire upstream region of the porcine THBD gene was found to drive a high expression in a porcine endothelial cell line and was therefore used to control hTM expression in transgenic pigs. The abundance of hTM was restricted to the endothelium, according to the predicted pattern, and the transgene expression of hTM was stably inherited to the offspring. When endothelial cells from pigs carrying the hTM transgene--either alone or in combination with an aGalTKO and a transgene encoding the human CD46-were tested in a coagulation assay with human whole blood, the clotting time was increased three- to four-fold (P<0.001) compared to wild-type and aGalTKO/CD46 transgenic endothelial cells. This, for the first time, demonstrated the anticoagulant properties of hTM on porcine endothelial cells in a human whole blood assay. CONCLUSIONS The biological efficacy of hTM suggests that the (multi-)transgenic donor pigs described here have the potential to overcome coagulation incompatibilities in pig-to-primate xenotransplantation.
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Maternal thromboembolism and a spectrum of placenta-mediated complications including the pre-eclampsia syndromes, fetal growth restriction, fetal loss, and abruption manifest a shared etiopathogenesis and predisposing risk factors. Furthermore, these maternal and fetal complications are often linked to subsequent maternal health consequences that comprise the metabolic syndrome, namely, thromboembolism, chronic hypertension, and type II diabetes. Traditionally, several lines of evidence have linked vasoconstriction, excessive thrombosis and inflammation, and impaired trophoblast invasion at the uteroplacental interface as hallmark features of the placental complications. "Omic" technologies and biomarker development have been largely based upon advances in vascular biology, improved understanding of the molecular basis and biochemical pathways responsible for the clinically relevant diseases, and increasingly robust large cohort and/or registry based studies. Advances in understanding of innate and adaptive immunity appear to play an important role in several pregnancy complications. Strategies aimed at improving prediction of these pregnancy complications are often incorporating hemodynamic blood flow data using non-invasive imaging technologies of the utero-placental and maternal circulations early in pregnancy. Some evidence suggests that a multiple marker approach will yield the best performing prediction tools, which may then in turn offer the possibility of early intervention to prevent or ameliorate these pregnancy complications. Prediction of maternal cardiovascular and non-cardiovascular consequences following pregnancy represents an important area of future research, which may have significant public health consequences not only for cardiovascular disease, but also for a variety of other disorders, such as autoimmune and neurodegenerative diseases.
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Medication errors, one of the most frequent types of medical errors, are a common cause of patient harm in hospital systems today. Nurses at the bedside are in a position to encounter many of these errors since they are there at the start of the process (ordering/prescribing) and the end of the process (administration). One of the recommendations from the IOM (Institute of Medicine) report, "To Err is Human," was for organizations to identify and learn from medical errors through event reporting systems. While many organizations have reporting systems in place, research studies report a significant amount of underreporting by nurses. A systematic review of the literature was performed to identify contributing factors related to the reporting and not reporting of medication errors by nurses at the bedside.^ Articles included in the literature review were primary or secondary studies, dated January 1, 2000 – July 2009, related to nursing medication error reporting. All 634 articles were reviewed with an algorithm developed to standardize the review process and help filter out those that did not meet the study criteria. In addition, 142 article bibliographies were reviewed to find additional studies that were not found in the original literature search.^ After reviewing the 634 articles and the additional 108 articles discovered in the bibliography review, 41 articles met the study criteria and were used in the systematic literature review results.^ Fear of punitive reactions to medication errors was a frequent barrier to error reporting. Nurses fear reactions from their leadership, peers, patients and their families, nursing boards, and the media. Anonymous reporting systems and departments/organizations with a strong safety culture in place helped to encourage the reporting of medication errors by nursing staff.^ Many of the studies included in this literature review do not allow results that can be generalized. The majority of them took place in single institutions/organizations with limited sample sizes. Stronger studies with larger sample sizes need to be performed, utilizing data collection methods that have been validated, to determine stronger correlations between safety cultures and nurse error reporting.^
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If allowed to continue unabated, the obesity epidemic may lead to the first decline in life expectancy in the developed world (Olshansky et al., 2005). Similar to the relationship between smoking habits in youth and adulthood, obesogenic dietary and physical activity habits in childhood may persist into adulthood (Kelder et al., 2002). Teaching children how to establish healthy eating habits and activity levels, as well as providing them the necessary resources to internalize and maintain these behaviors, may be the key to curbing this epidemic.^ A school-based obesity prevention approach is advantageous for many reasons including exposure to large captive audiences, reduced costs of sustainability and long-term maintenance, and generalizability of models and results across multiple populations. The effectiveness of school-based programs has been researched over the past 20 years, with promising results.^ Social marketing is a program-planning process that “facilitates the acceptance, rejection, modification, abandonment, or maintenance of particular behaviors” (Grier & Bryant, 2005). Social marketing has been shown to be effective in a variety of public health applications including improving diet, increasing physical activity, and preventing substance abuse. It is hypothesized that social marketing could further enhance the effectiveness of the Coordinated Approach To Child Health (CATCH) Central Texas Middle School Project, a school-based obesity prevention program.^ The development, implementation, and initial evaluation of the get ur 60 campaign, to promote the Center for Disease Control and Prevention (CDC) recommended sixty minutes of daily activity, is described in this paper. Various components of the get ur 60 campaign were assessed to evaluate the effectiveness of the campaign during the first semester of implementation. At the end of the spring semester focus groups were held to collect student reactions to the first semester of the get ur 60 campaign.^ The initial results from the first semester of get ur 60 have demonstrated that the campaign as designed was feasible to implement, accepted at all intervention schools, and resulted in a measure of success. ^
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These three manuscripts are presented as a PhD dissertation for the study of using GeoVis application to evaluate telehealth programs. The primary reason of this research was to understand how the GeoVis applications can be designed and developed using combined approaches of HC approach and cognitive fit theory and in terms utilized to evaluate telehealth program in Brazil. First manuscript The first manuscript in this dissertation presented a background about the use of GeoVisualization to facilitate visual exploration of public health data. The manuscript covered the existing challenges that were associated with an adoption of existing GeoVis applications. The manuscript combines the principles of Human Centered approach and Cognitive Fit Theory and a framework using a combination of these approaches is developed that lays the foundation of this research. The framework is then utilized to propose the design, development and evaluation of “the SanaViz” to evaluate telehealth data in Brazil, as a proof of concept. Second manuscript The second manuscript is a methods paper that describes the approaches that can be employed to design and develop “the SanaViz” based on the proposed framework. By defining the various elements of the HC approach and CFT, a mixed methods approach is utilized for the card sorting and sketching techniques. A representative sample of 20 study participants currently involved in the telehealth program at the NUTES telehealth center at UFPE, Recife, Brazil was enrolled. The findings of this manuscript helped us understand the needs of the diverse group of telehealth users, the tasks that they perform and helped us determine the essential features that might be necessary to be included in the proposed GeoVis application “the SanaViz”. Third manuscript The third manuscript involved mix- methods approach to compare the effectiveness and usefulness of the HC GeoVis application “the SanaViz” against a conventional GeoVis application “Instant Atlas”. The same group of 20 study participants who had earlier participated during Aim 2 was enrolled and a combination of quantitative and qualitative assessments was done. Effectiveness was gauged by the time that the participants took to complete the tasks using both the GeoVis applications, the ease with which they completed the tasks and the number of attempts that were taken to complete each task. Usefulness was assessed by System Usability Scale (SUS), a validated questionnaire tested in prior studies. In-depth interviews were conducted to gather opinions about both the GeoVis applications. This manuscript helped us in the demonstration of the usefulness and effectiveness of HC GeoVis applications to facilitate visual exploration of telehealth data, as a proof of concept. Together, these three manuscripts represent challenges of combining principles of Human Centered approach, Cognitive Fit Theory to design and develop GeoVis applications as a method to evaluate Telehealth data. To our knowledge, this is the first study to explore the usefulness and effectiveness of GeoVis to facilitate visual exploration of telehealth data. The results of the research enabled us to develop a framework for the design and development of GeoVis applications related to the areas of public health and especially telehealth. The results of our study showed that the varied users were involved with the telehealth program and the tasks that they performed. Further it enabled us to identify the components that might be essential to be included in these GeoVis applications. The results of our research answered the following questions; (a) Telehealth users vary in their level of understanding about GeoVis (b) Interaction features such as zooming, sorting, and linking and multiple views and representation features such as bar chart and choropleth maps were considered the most essential features of the GeoVis applications. (c) Comparing and sorting were two important tasks that the telehealth users would perform for exploratory data analysis. (d) A HC GeoVis prototype application is more effective and useful for exploration of telehealth data than a conventional GeoVis application. Future studies should be done to incorporate the proposed HC GeoVis framework to enable comprehensive assessment of the users and the tasks they perform to identify the features that might be necessary to be a part of the GeoVis applications. The results of this study demonstrate a novel approach to comprehensively and systematically enhance the evaluation of telehealth programs using the proposed GeoVis Framework.
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Incoming students in the University have education deficiencies, so universities studies require a sound basis of scientific knowledge. In this project are analysed instruments to reinforcing knowledge in those areas related to the studies that students are about to embark on public Spanish universities. There are important differences among universities and, in each university there are great differences among titles. Initial courses (cursos cero) are widespread (in 50% of universities) that selfevaluation instruments (14 % of universities). It is necessary to improve diffusion of those instruments because it is not possible to evaluate them. So are proposed the next actuations: to make regular standard surveys for professors and students; to publish results of surveys; public universities should institutionalize their basic training offer and improve the dissemination of this offer especially through the web. This paper presents a questionnaire to assess student opinion about these tools. To analyze the effectiveness, and make an initial estimate of the evaluation of these tools, we conducted a pilot test of the questionnaire with 68 students at the University of Extremadura. The results of preliminary statistical analysis conducted on the pilot test indicate that the survey results are reliable. A global evaluation of both tools, with a scale of 1 to 5, gave an average score of 3.29 for initial courses and 3.41 for selfevaluation. The 72.9% of the students consider the "self assessment" more effective than the "initial course"
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A useful strategy for improving disaster risk management is sharing spatial data across different technical organizations using shared information systems. However, the implementation of this type of system requires a large effort, so it is difficult to find fully implemented and sustainable information systems that facilitate sharing multinational spatial data about disasters, especially in developing countries. In this paper, we describe a pioneer system for sharing spatial information that we developed for the Andean Community. This system, called SIAPAD (Andean Information System for Disaster Prevention and Relief), integrates spatial information from 37 technical organizations in the Andean countries (Bolivia, Colombia, Ecuador, and Peru). SIAPAD was based on the concept of a thematic Spatial Data Infrastructure (SDI) and includes a web application, called GEORiesgo, which helps users to find relevant information with a knowledge-based system. In the paper, we describe the design and implementation of SIAPAD together with general conclusions and future directions which we learned as a result of this work.