Sex-differentiated free play behavior: Effects of teacher modeling, location, and gender.

82 preschoolers' (40–62 mo old) rates of behavior were observed toward play activities (e.g. dolls, trucks) and teacher-related variables. Results show that both sexes increased rates of participation in response to teacher presence in male and female sex-typed activity areas during free play. Girls, however, responded more consistently to teacher presence than did boys, who modulated their responses according to both the sex typing of the activity and the sex of the teacher. Findings indicate that typically observed teacher behavior during free play may contribute significantly to reported patterns of sex-differentiated play. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Health-related possible selves in young and middle adulthood.

The construct of possible selves was used to examine when, in the adult life span, health-related goals become dominant. It was predicted that by middle age most adults would have health-related possible selves and that the strength of self-regulatory variables associated with health-related possible selves would be related to reported health behaviors. Data collected from 171 young (aged 24–39 yrs) and middle-aged (aged 40–59 yrs) adults showed that health-related possible selves become predominant in midlife. In addition, both young and middle-aged adults reported more feared than hoped-for selves in the realm of health. Perceived self-efficacy and number of goal-oriented activities to avoid feared health-relevant selves were significant predictors of health behaviors. Results are discussed in relation to theoretical perspectives on self and health processes over the life span. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Detection of adulteration of locust bean gum with guar gum by capillary electrophoresis and polarized light microscopy

Capillary electrophoresis (CE) and polarized light microscopy (PLM) were utilized in the detection of the adulteration of locust bean gum with guar gum. For CE analyses, standards of locust bean and guar gums were extracted with 30% CH₃CN, removing the residual proteins from the gum matrix. A 8.75 mM NaH₂PO₄-20.6 mM Na₂B₄O₇ buffer, pH 9, was used to separate these proteins and to identify marker proteins that were present in the guar gum. These markers did not co-migrate with components in the extracts of mechanically processed locust bean gum, and are used as indicators of adulteration. Using PLM with toluidine blue and iodine staining techniques, unadulterated locust bean gum samples were distinguished from mixed samples through the differential staining of components in locust bean versus guar and tara gums. These experiments in the use of CE and PLM provide orthogonal and complementary methods for the verification of 'true' positives and the elimination of 'false' positives.     

Who said what? Source memory for narrator and character agents in literary short stories.

One dimension of reading literacy involves the tracking of agents associated with the text. In a literary short story, there is a society of character agents and pragmatic agents. This study investigated the relative salience of different classes of agents in memory. Two experiments measured source memory as an index of agent salience in long-term memory. Patterns of source memory scores supported an invisible third-person narrator hypothesis and an agent amalgamation hypothesis, but not a structural prominence hypothesis: First-person narrator > nonnarrator character > third-person narrator > 0. Statement detection parameters did not significantly differ among the 3 classes of agents, so differences in source memory could not be explained by differences in the content of the speech acts. Source memory scores also could not be explained by surface features of the text, differences among readers, and sophisticated guessing on the basis of a story abstract. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exercise duration and mood state: How much is enough to feel better?

The effects of exercise duration on mood state were examined. In a repeated-measures design, the Profile of Mood States inventory (D. M. McNair, M. Lorr, & L. F. Droppleman, 1971) was administered before and after 1 quiet resting trial and 3 exercise trials of 10, 20, and 30 min on a bicycle ergometer. Heart rate levels were controlled at 60% of the participant's estimated V02max level. An overall analysis of variance found improved levels of vigor with reduced levels of confusion, fatigue, and total negative mood. Planned analyses revealed that the improvements in vigor, fatigue, and total mood occurred after 10 min of exercise, with progressive improvements in confusion over 20 min and with no additional improvement over longer periods. These results complement current recommendations, which suggest that to experience positive fitness and health benefits, healthy adults should participate in a total of 30 min of moderate physical exercise daily, accumulated in short bouts throughout the day. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Tobacco withdrawal signs and symptoms among women with and without a history of depression.

A past history of depression is associated with a decreased likelihood of quitting smoking. Tobacco withdrawal may be a mechanism through which depression history impedes smoking cessation. This research examined the influence of depression history on unmedicated tobacco withdrawal signs (polysomnographic measures of sleep) and symptoms (self-reported urge, negative affect, hunger, and sleep) among women (N/& =/&13). Depression history was associated with differential withdrawal-induced changes in several REM sleep parameters. Self-report and other polysomnography (sleep fragmentation, slow-wave sleep) measures displayed statistically significant withdrawal effects but did not discriminate between depression history groups. These results suggest that REM sleep parameters may be sensitive to differential tobacco withdrawal responses that are not readily apparent through self-reported symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Parent–child attitude congruence on type and intensity of physical activity: Testing multiple mediators of sedentary behavior in older children.

Objective: This study examined parent–child attitudes on value of specific types and intensities of physical activity, which may explain gender differences in child activity, and evaluated physical activity as a mechanism to reduce time spent in sedentary behaviors. Design: A community sample of 681 parents and 433 children (mean age 9.9 years) reported attitudes on importance of vigorous and moderate intensity team and individually performed sports/activities, as well as household chores. Separate structural models (LISREL 8.7) for girls and boys tested whether parental attitudes were related to child TV and computer via child attitudes, sport team participation, and physical activity, controlling for demographic factors. Main Outcome Measures: Child 7-day physical activity, sport teams, weekly TV, computer. Results: Parent–child attitude congruence was more prevalent among boys, and attitudes varied by ethnicity, parent education, and number of children. Positive parent–child attitudes for vigorous team sports were related to increased team participation and physical activity, as well as reduced TV and computer in boys and girls. Value of moderate intensity household chores, such as cleaning house and doing laundry, was related to decreased team participation and increased TV in boys. Only organized team sports, not general physical activity, was related to reduced TV and computer. Conclusion: Results support parents’ role in socializing children’s achievement task values, affecting child activity by transferring specific attitudes. Value of vigorous intensity sports provided the most benefits to activity and reduction of sedentary behavior, while valuing household chores had unexpected negative effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Theory and practice of ubiquitous quantitative chemical analysis using conventional computer optical disk drives

We demonstrate a new attractive approach for ubiquitous quantitative chemical or biological sensing when analog signals are acquired from conventional optical disk drives, and these signals are used for quantitative detection of optical changes of sensing films deposited on conventional CD and DVD optical disks. Our developed analytical model of the operation of this Lab-on-DVD system describes the optical response of sensing films deposited onto the read surface of optical disks by taking into account the practical aspects of system performance that include possible reagent leaching effects, water sampling (delivering) efficiency, and possible changes of the film morphology after water removal. By applying a screen-printing process, we demonstrated a laboratory-scale automated production of sensing films with an average thickness of approximately 10 microm and a thickness relative standard deviation of <3% across multiple films. Finally, we developed a system for delivery of water-sample volumes to sensing films on the disk that utilized a multifunctional jewel case assembly.