This study examined gender and developmental differences in exercise-related beliefs and exercise behaviors of 286 racially diverse youth and explored factors predictive of exercise. Compared to males, females reported less prior and current exercise, lower self-esteem, poorer health status, and lower exercise self-schema. Adolescents, in contrast to pre-adolescents, reported less social support for exercise and fewer exercise role models. In a path model, gender, the benefits/barriers differential, and access to exercise facilities and programs directly predicted exercise. Effects of grade, perceived health status, exercise self-efficacy, social support for exercise, and social norms for exercise on exercise behavior, were mediated through the benefits/barriers differential. Effect of race on exercise was mediated by access to exercise facilities and programs. Continued exploration of gender and developmental differences in variables influencing physical activity can yield valuable information for tailoring exercise promotion interventions to the unique needs of youth.

In this paper we consider distributed optimization problems over a multi-agent network, where each agent can only partially evaluate the objective function, and it is allowed to exchange messages with its immediate neighbors. Differently from all existing works on distributed optimization, our focus is given to optimizing a class of non-convex problems, and under the challenging setting where each agent can only access the zeroth-order information (i.e., the functional values) of its local functions. For different types of network topologies such as undirected connected networks or star networks, we develop efficient distributed algorithms and rigorously analyze their convergence and rate of convergence (to the set of stationary solutions). Numerical results are provided to demonstrate the efficiency of the proposed algorithms. Furthermore, for given J independent samples of {(φ j , ξ j )} J j=1 , we defineḠ µ (z, φ, ξ) as the sample average:ḠLemma 1 [34, Lemma 4.2] Suppose that Assumption A holds true for function ψ : R Q → R. Then we have the followingwhereσ 2 := 2Q[K 2 + σ 2 + µ 2L2 Q].

To enhance our understanding of exercise adherence, predictors of adherence based on social-cognitive theory were compared with those derived from a trait approach. A community-based sample of older, sedentary men and women was administered the Self-Motivation Inventory and a self-efficacy questionnaire. Subjects were randomly assigned to one of three exercise regimens or to an assessment-only control condition for the following year. The subjects in the exercise conditions recorded each bout of exercise and rated the experience in terms of perceived exertion, enjoyment, and convenience (PEEC) on monthly logs. Based on social-cognitive theory, it was postulated that self-efficacy and certain aspects of the exercise bout itself, such as PEEC, would influence exercise adherence more than the general trait of self-motivation. Self-efficacy was significantly associated with exercise adherence at both 6 months and 1 year (rs = .42 and .44, respectively); self-motivation was not. Contrary to expectations, the PEEC components measured during the first 6 months did not make a significant contribution to the variance in adherence during the second 6 months.

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Nicotine intake, menstrual and smoking withdrawal symptomatology, and baseline cortisol and MHPG were assessed in nine women smokers under conditions of ad lib smoking and overnight abstinence in three menstrual phases (early follicular, mid-to-late follicular, and late luteal). A trend towards higher nicotine intake (p < 0.10) was observed in the mid-to-late follicular phase. Although menstrual symptomatology was not significantly elevated during the smoking abstinence condition overall, abstinence appeared to prevent the normal reduction in symptomatology during the mid-to-late follicular phase that occurred under conditions of ad lib smoking. Menstrual and withdrawal symptoms were highly correlated, and both were most pronounced during the late luteal/abstinence condition. The smoking-specific item "craving" reflected this pattern, though in attenuated form, suggesting that the observed exacerbation of withdrawal symptomatology was not simply due to generalized dysphoria, as queried in both instruments. MHPG was significantly elevated in the late luteal phase, whereas cortisol was significantly higher during ad lib smoking than during abstinence and tended to be highest in the mid-to-late follicular phase. Further investigation will be needed to determine the functional significance of these findings for understanding and treating smoking in women.

We introduce a novel procedure to compute system optimal routings in a dynamic trac network. Fictitious play is utilized within a game of identical interests wherein vehicles are treated as players with the common payo of average trip time experienced in the network. This decentralized approach via repeated play of the ®ctitious game is proven to converge to a local system optimal routing. Results from a largescale computational test on a real network are presented. Ó

Wireless sensor networks pose numerous fundamental coordination problems. For example, in a number of application domains including homeland security, environmental monitoring, and surveillance for military operations, a network's ability to efficiently manage power consumption is extremely critical because direct user intervention after initial deployment is severely limited. In these settings, limited battery life gives rise to the basic coordination problem of maintaining coverage while maximizing the network's lifetime. In this paper, we propose a distributed scheme for efficient power management in sensor networks that is guaranteed to identify suboptimal topologies in an online fashion. Our scheme is based on a general (game-theoretic) mathematical structure that induces a natural mapping between the informational layer and the physical layer. We provide sufficient conditions for the convergence of the algorithm to a pure Nash equilibrium and characterize the performance of the algorithm in terms of coverage. We also present encouraging performance results on a MicaZ testbed as well as on large-scale topologies (obtained via simulation).