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401.
Activities related to body donation programs, such as donor memorial ceremonies, provide the opportunity to complement student training, especially with regard to the ethical and humanistic elements involved in medical training. This study sought to assess the impact of a ceremony in honor of the body donors has on ethical and humanistic attitudes in medical students. Medical students were surveyed about their perceptions of changes in themselves, respect for donors and donor families, and their relationship with patients. The effect of the students' contact with the family of the donor was analyzed in students who had contact with the cadaver in the dissection room and had either participated or not participated in the donor memorial ceremony. A total of 370 questionnaires were answered by first-, second-, and third-year medical students at the Federal University of Health Sciences of Porto Alegre in 2017. The students who participated in the ceremony presented more positive responses in relation to commitment to their studies, reflection on death, and positive development of empathy when compared to those who did not attend the ceremony. Most of the students that attended the ceremony suggested the event led to an improvement in the doctor–patient relationship. These results suggest that cadaver dissection with accompanied memorial ceremony involving contact with donor families is an effective means of fostering ethical and humanistic attitudes among medical students from the beginning of the course.  相似文献   
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Using the famous Birthday problem, we present here a practical activity that allows students to perceive the basic reasoning behind simulation and explore its potential. Through a playful approach with probabilities, students are led along a path that illustrates difficulties with intuition and introduces them to theoretical results for sample proportions.  相似文献   
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Multiple-choice questions (MCQs) play a key role in standardised testing and in-class assessment. Research into the influence of within-item response order on MCQ characteristics has been mixed. While some researchers have shown preferential selection of response options presented earlier in the answer list, others have failed to replicate these results. This paper investigates a possible explanation for these mixed findings by assessing the influence of distractor strength on MCQ response order effects. A real-world assessment was administered to 232 undergraduates in which the response order within items was systematically varied. A generalised multilevel model was then used to show a significant interaction between distractor strength and response position with regard to response behaviour. Furthermore, the effect was found to be independent of student ability. These findings have implications for MCQ test construction, minimising the negative consequences of MCQ test exposure and promoting improved test-taking strategies.  相似文献   
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SEAD method estimates the direction-of-arrival angles on an uniform linear array based on the difference between the two largest singular values, what is called differential spectrum. Although it presented an outstanding performance, the ability to indicate the source positions was not elucidated yet. Inspired by the differential spectrum formulation we derived a total differential spectrum and found out that the matrix norm induced by the vector 2-norm of a modified spatial covariance matrix can be used to estimate the direction-of-arrival of multiple plane waves. Indeed we show that matrix norms are estimators and we propose their use instead of the singular value decomposition in SEAD-based methods. We present a general mathematical expression in order to explicit the operating principles of the proposed methods. Consequently, we were able to explain how the relation between the arriving and the search angles produces the larger peaks on the differential spectrum. To evaluate the important role played by matrix norms, a thousand experiments were carried out. They showed that the proposed approach proved to be as accurate as the previous SEAD-based methods, while providing a significant reduction on runtime. It also outperformed well-established methods like MODEX regarding the estimation error.  相似文献   
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The consensus problem for networks of multiple agents consists in reaching an agreement between certain coordinates of interest using a distributed controller. It may be desirable that all the agents find a consensus at a given desired leader coordinate (Leader Follower Consensus Problem LFCP), or it may be only necessary that they agree at a certain coordinates value (Leaderless Consensus Problem LCP). Consensus has many practical applications in robot networks systems, where the interconnection of the agents may present variable time delays, hence rendering the stability analysis and control design more complex. Another problem that may arise is the possible lack of velocity measurements. In this work, a Proportional plus damping injection (P + d) controller together with a linear velocity observer is introduced. Our approach is able to solve both the LFCP and the LCP in networks of robots modeled as undirected weighted graphs with unknown asymmetric (bounded) variable time delays. Local (semi global) asymptotic stability is proven and simulation results are provided to test the performance of the proposed scheme.  相似文献   
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Purpose: Several studies have demonstrated that physiological variables predict cycling endurance performance. However, it is still unclear whether the predictors will change over different performance durations. The aim of this study was to assess the correlations between physiological variables and cycling time trials with different durations. Methods: Twenty trained male cyclists (maximal oxygen uptake [VO2max] = 60.5 ± 5.6 mL/kg/min) performed 4 separate experimental trials during a 2-week period. Cyclists initially completed an incremental exercise test until volitional exhaustion followed by 3 maximal cycling time trials on separate days. Each time trial consisted of 3 different durations: 5 min, 20 min, and 60 min performed in a randomized order. Results: The main results showed that the physiological measures strongly correlated with long cycling performances rather than short and medium time trials. The time-trial mean power output was moderately high to highly correlated with peak power output and VO2max (r = .61–.87, r = .72–.89, respectively), and was moderately to highly correlated with the lactate threshold Dmax method and second ventilatory threshold (r = .52–.75, r = .55–.82, respectively). Conclusions: Therefore, trained cyclists should develop maximal aerobic power irrespective of the duration of time trial, as well as enhancements in metabolic thresholds for long-duration time trials.  相似文献   
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Based on a socio-ecological framework for physical education (PE), this study explored and analysed the perspectives of physically active and inactive adolescent boys and girls with different socioeconomic status (SES), regarding the meanings that PE had on their physical activity (PA) lifestyles throughout childhood and adolescence. An interpretative and qualitative design was adopted and operationalised through an individual two-hours in-depth interview. Thematic analysis identified five main themes that distinguish active from inactive adolescents: ‘Early experiences of PE at primary school’; ‘PE experiences in middle and secondary school’; ‘Friendly, professional and pedagogue. That’s what I want from my PE teacher’; ‘Friends in PE and PA’; ‘Active lifestyles? Are schools and PE ready for making a difference?…’. Regardless of the lifestyle, girls revealed more PE negative experiences, related to uninteresting and competitive activities, groups’ constitution and logistic factors. SES played a major role on their PA and PE experiences, with low SES adolescents having limited opportunities inclusively within the primary school PE context. This study provides evidence for the importance of promoting positive PE and PA experiences in early years. Based on adolescents’ voices, several recommendations are discussed that can be considered for improving PE professionals’ effectiveness in promoting active lifestyles.  相似文献   
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