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61.
The purpose of this study was to explore athletes' experiences with doping education and their recommendations to improve current education to create more effective doping prevention interventions. Following a constructivist approach, interviews were conducted with 21 athletes and analyzed inductively with thematic analysis. Six themes were identified relating to athletes' experiences with doping education and recommendations for improving it. Athletes commonly described receiving insufficient doping education during adolescence, highlighting the need for increased doping prevention efforts. Recommendations for future educational programs include addressing doping prevention collaboratively, implementing education at younger ages, and assuring the programs are engaging and interactive.  相似文献   
62.
In the categorical approach to the foundations of quantum theory, one begins with a symmetric monoidal category, the objects of which represent physical systems, and the morphisms of which represent physical processes. Usually, this category is taken to be at least compact closed, and more often, dagger compact, enforcing a certain self-duality, whereby preparation processes (roughly, states) are interconvertible with processes of registration (roughly, measurement outcomes). This is in contrast to the more concrete “operational” approach, in which the states and measurement outcomes associated with a physical system are represented in terms of what we here call a convex operational model: a certain dual pair of ordered linear spaces–generally, not isomorphic to one another. On the other hand, state spaces for which there is such an isomorphism, which we term weakly self-dual, play an important role in reconstructions of various quantum-information theoretic protocols, including teleportation and ensemble steering. In this paper, we characterize compact closure of symmetric monoidal categories of convex operational models in two ways: as a statement about the existence of teleportation protocols, and as the principle that every process allowed by that theory can be realized as an instance of a remote evaluation protocol—hence, as a form of classical probabilistic conditioning. In a large class of cases, which includes both the classical and quantum cases, the relevant compact closed categories are degenerate, in the weak sense that every object is its own dual. We characterize the dagger-compactness of such a category (with respect to the natural adjoint) in terms of the existence, for each system, of a symmetric bipartite state, the associated conditioning map of which is an isomorphism.  相似文献   
63.
RESUMEN

En una amplia variedad de tareas de detección de objetivos auditivos y visuales, la ejecución era escasamente influida por el número de no-objetivos simultáneos, pero le afectaba si los objetivos simultáneos debían ser detectados por separado. Se ha sugerido que sólo los objetivos necesitan pasar por un sistema de capacidad limitada que conduce a la conciencia; los no-objetivos pueden ser identificados y rechazados por un procesamiento paralelo e inconsciente. Puesto que las palabras no- objetivo, por ejemplo, se pueden rechazar en base al significado, el estímulo debe ser completamente analizado antes de pasar por el sistema de capacidad limitada. De modo general, la disminución en la ejecución debida a la atención dividida es acusada siempre que la estimulación simultánea (psicofísica, verbal, etc.) se deba identificar por separado, puesto que bajo estas circunstancias cualquier estimulación debe pasar por un sistema de capacidad limitada hasta la conciencia.  相似文献   
64.
Promoting the ability to reason generatively about novel phenomena and problems students may encounter in their everyday lives is a major goal of science education. This goal proves to be a formidable challenge in domains, such as molecular genetics, for which the accumulated scientific understandings are daunting in both amount and complexity. To develop effective instruction that fosters generative reasoning we need to have a sound understanding of the types of knowledge in the domain that are critical for such reasoning. In this study I examined the ensemble of knowledge, both general and domain-specific, undergraduate students employed in reasoning about problems in genetics. I found that students initially formulate a solution in terms that are not domain specific and that serve as a frame–solution frame–that outlines and constrains a more specific and domain-appropriate explanation. This solution frame is then filled in with two powerful forms of domain-specific knowledge I term: domain-specific heuristics and domain-specific explanatory schemas. These knowledge forms embody understandings of central mechanisms and entities in molecular genetics. By invoking these domain-specific knowledge forms, students were able to reason about a variety of both familiar and novel genetics problems. I present a cognitive model that highlights the role of these powerful conceptual understandings in promoting generative reasoning in genetics.  相似文献   
65.
Abstract

This study developed and validated an Asthma Multidimensional Health Locus of Control (AMHLC) scale using 186 asthmatics aged 13 to 55 years recruited from 46 pharmacies in the Hunter Valley, Australia. The construct validity and internal consistency of the scale were demonstrated using principal components factor analysis and Cronbach's alpha respectively. Although correlations were modest, findings indicate that asthmatics with higher “Powerful Others” locus of control perceived they had a better quality of doctor-patient relationship; the opposite was found for those with higher “Chance” scores. Powerful Others orientation was also associated with expectations and valuation of services doctors' provide. Knowledge of asthma was not related in the expected direction with the new scale, nor were clinical indices of asthma severity. Younger asthmatics had higher Chance scores while older asthmatics tended toward higher Powerful Others orientation. Overall, the AMHLC instrument achieved suitable measurement properties to allow further investigation of health care behavior in people with asthma.  相似文献   
66.
Abstract

Increasing evidence suggests that regular physical activity can have considerable psychological, as well as physical, benefits in the elderly. Although factors such as exercise dosage may be implicated in exercise-induced affect responses, it has also been suggested that social and psychological factors might influence this relationship. This study examined the roles played by exercise environment (group versus alone) and self-efficacy in affective change in 80 older adults (M age = 66 yrs) over the course of three acute exercise bouts. Using latent growth curve methodology and statistically controlling for duration and intensity of exercise, we were able to demonstrate that social (group) environments resulted in statistically significant improvements in feeling state responses when contrasted with a condition in which the participants exercised alone. In addition, increases in self-efficacy were associated with more positive and less negative feeling states. Environmental factors that might influence the exercise-affect response are discussed and recommendations for subsequent exercise, efficacy, affect research made.  相似文献   
67.
68.
Past research shows that authoritarian individuals hold strong opinions about a variety of political and social issues, such as race relations and military conflict. What has not been established, though, is the amount of general political knowledge that authoritarians possess. In this study, three groups of college students were administered Altemeyer's Right-Wing Authoritarianism (RWA) scale; most of them also received items assessing general political knowledge and specific knowledge about the 2000 presidential election, as well as items assessing interest in politics. Relative to students with low RWA scores, those with high scores possessed less political knowledge; moreover, they expressed less interest in learning about politics. In general, authoritarianism was unrelated to how individuals got their political information or how credible they found their sources. The implication that authoritarians hold strong attitudinal beliefs with weak political knowledge is discussed.  相似文献   
69.
This paper presents a latent growth SEM approach for the estimation of treatment effects, and power to detect such effects, within a true experimental design setting in which subjects are randomly assigned to treatment and control conditions. Power estimation is a critical component of intervention experiment design and the testing of their results. Although researchers have become increasingly sophisticated in applying tests for statistical significance in intervention contexts, few are aware of the power of these tests. The issues raised in this paper are not new; however, reminding researchers to consider these points is important. Exactly how the researcher handles these issues will depend on the questions asked and the resources available, as well as other considerations. Discussion underscores the relationship between the reliability of a study's measures and concomitant increases in power obtained within the SEM framework.  相似文献   
70.
C-quence is a software application that matches sequential patterns of qualitative data specified by the user and calculates the rate of occurrence of these patterns in a data set. Although it was designed to facilitate analyses of face-to-face interaction, it is applicable to any data set involving categorical data and sequential information. C-quence queries are constructed using a graphical user interface. The program does not limit the complexity of the sequential patterns specified by the user.  相似文献   
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