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In this study, we evaluated several components of a pedometer-based intervention with children in an elementary-school-aged classroom, across 24-h sessions. The intervention included combinations of self-monitoring, goal setting, feedback, and reinforcement, and data were analyzed at both the classroom level (i.e., average daily step totals) and the individual level (i.e., daily step totals), across phases. The highest levels of physical activity were observed when components of self-monitoring, public posting, goal setting, and feedback with reward were applied concurrently.  相似文献   
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In March 2020, in response to the COVID-19 pandemic, Canadian provincial governments instituted a variety of public health measures that included social distancing and isolation, which may have had unintended consequeses. According to the Loneliness and Sexual Risk Model, gay, bisexual, and other men who have sex with men (GBM) often cope with loneliness through risky sexual behaviors. Previous studies have demonstrated that COVID-19 measures such as social distancing and isolation led to increases in loneliness; thus, these measures may also have led to elevated sexual risk-taking among some GBM. Participants were recruited from an ongoing cohort study on GBM health and well-being, and were included in the current analysis if they had completed relevant study questions (n = 1134). GBM who reported lower levels of social support pre-COVID-19, were younger, and lived alone each reported greater loneliness during the first year of COVID-19. Although feelings of loneliness did not predict sexual risk-taking within the first year of COVID-19, loneliness did predict greater sexual risk-taking 6 months later. Additionally, younger GBM and those living alone were more likely to engage in sexual risk-taking at both COVID-19 data collection points. These findings offer some support of the Loneliness and Sexual Risk Model; however, it is possible that the unique circumstances of the COVID-19 pandemic resulted in a temporary suspension of this association, as many GBM took steps to protect themselves and partners in the context of COVID-19.  相似文献   
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Introduction     
Theoretical Medicine and Bioethics -  相似文献   
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Given a variety we study the existence of a class such that S1 every A can be represented as a global subdirect product with factors in and S2 every non-trivial A is globally indecomposable. We show that the following varieties (and its subvarieties) have a class satisfying properties S1 and S2: p-algebras, distributive double p-algebras of a finite range, semisimple varieties of lattice expansions such that the simple members form a universal class (bounded distributive lattices, De Morgan algebras, etc) and arithmetical varieties in which the finitely subdirectly irreducible algebras form a universal class (f-rings, vector groups, Wajsberg algebras, discriminator varieties, Heyting algebras, etc). As an application we obtain results analogous to that of Nachbin saying that if every chain of prime filters of a bounded distributive lattice has at most length 1, then the lattice is Boolean.We wish to thank Lic. Alfredo Guerin and Dr. Daniel Penazzi for helping us with linguistics aspects. We are indebted to the referee for several helpful suggestions. We also wish to thank Professor Mick Adams for providing us with several reprints and useful e-mail information on the subject.Suported by CONICOR and SECyT (UNC).  相似文献   
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We extend to the predicate frame a previous characterization of the maximal intermediate propositional constructive logics. This provides a technique to get maximal intermediate predicate constructive logics starting from suitable sets of classically valid predicate formulae we call maximal nonstandard predicate constructive logics. As an example of this technique, we exhibit two maximal intermediate predicate constructive logics, yet leaving open the problem of stating whether the two logics are distinct. Further properties of these logics will be also investigated.Presented by H. Ono  相似文献   
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Risk perception of natural hazards has been widely studied as one of the potential determinants of people's behaviors and behavioral intentions. However, individual differences can also affect risk perception. The present work focused on the link between an individual cognitive mindset (i.e., level of holism) and flood-risk perception. It also assessed the consequences of such a link on public and personal mitigation intentions, taking into account the sense of connection with the environment, the psychological distance from the adverse event, and the role played by previous personal experience with flooding. Our study (N = 191) showed that the individual cognitive style predicted risk perceptions and personal (for both experienced and no-experience groups) and public (only for experienced group) mitigation intentions, through the mediation of the sense of connection with the environment and the psychological distance from the adverse event. Results are discussed in terms of their practical implications for public communication and policies about environmental hazards.  相似文献   
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Silver ME  Field TM  Sanders CE  Diego M 《Adolescence》2000,35(140):663-669
In the present study, 31 of 89 adolescents responded affirmatively to the following statement: "Sometimes I get so angry that I worry I will become violent." These adolescents (the anger group) were compared with the nonanger group, and several differences were found. The anger group (1) reported less intimacy with parents, received less support from them, and was less close to siblings; (2) had more opposite-sex friends, dated more frequently, and more frequently had a boyfriend or girlfriend; (3) had a lower grade point average; (4) were more depressed; and (5) used marijuana more frequently. Results of a regression analysis revealed that depression and dating were the only significant predictors of anger, explaining 17% of the variance.  相似文献   
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