The Effects of Athletic Participation on Self-Concept, Daily School Attendance, and Grade Point Average of Female Seventh-Grade Students in Urban Schools

This study examined the effects of athletic participation on self-concept, daily school attendance, and grade point average on 503 seventh grade students in urban middle schools. A 2 x 3 factorial MANOVA analyzed self-concept data to determine differences in self-concept associated with the levels of athletic participation with that of pre- and post-treatment test periods. Tukey\u27s post hoc tests were incorporated when a significant F ratio was demonstrated (p\u3c 0.05). Significant differences were noted in four areas of self-concept as defined by Piers-Harris (1984): (1) intellectual and school status (Tukey, p\u3c 0.05), (2) physical appearance and attributes (Tukey, p\u3c 0.05), (3) anxiety (Tukey, p\u3c 0.05), and (4) popularity (Tukey, p\u3c 0.05). No significant differences were noted in three areas of self-concept: (1) behavior, (2) happiness and satisfaction, and (3) self-concept total. A 3 x 3 factorial ANOVA demonstrated statistical differences in daily school attendance between female students participating in interscholastic athletics with female students not participating in interscholastic athletics. Daily school attendance reports were collected to coincide with three grading periods. Tukey\u27s post hoc tests were incorporated when a significant F ratio was demonstrated (Tukey, p\u3c 0.05). Students not participating in interscholastic athletics noted higher absenteeism than students who participated in interscholastic athletics (Tukey, p\u3c 0.05). A 3 x 3 factorial ANOVA demonstrated statistical differences in grade point averages between female students participating in interscholastic athletics with those female students not participating in interscholastic athletics. Grade point averages of the two-sport participants were significantly higher than the one-sport participants (Tukey, p\u3c 0.05). Grade point averages of the one-sport participants were significantly higher than the no-sport participants (Tukey, p\u3c 0.05). Results suggest positive effects of athletic participation on self-concept, daily school attendance, and grade point average of female seventh grade students in urban middle schools participating in interscholastic sports programs

Effect of Brief Biofeedback via a Smartphone App on Stress Recovery: Randomized Experimental Study.

BACKGROUND:Smartphones are often vilified for negatively influencing well-being and contributing to stress. However, these devices may, in fact, be useful in times of stress and, in particular, aid in stress recovery. Mobile apps that deliver evidence-based techniques for stress reduction, such as heart rate variability biofeedback (HRVB) training, hold promise as convenient, accessible, and effective stress-reducing tools. Numerous mobile health apps that may potentially aid in stress recovery are available, but very few have demonstrated that they can influence health-related physiological stress parameters (eg, salivary biomarkers of stress). The ability to recover swiftly from stress and reduce physiological arousal is particularly important for long-term health, and thus, it is imperative that evidence is provided to demonstrate the effectiveness of stress-reducing mobile health apps in this context. OBJECTIVE:The purpose of this research was to investigate the physiological and psychological effects of using a smartphone app for HRVB training following a stressful experience. The efficacy of the gamified Breather component of the Happify mobile health app was examined in an experimental setting. METHODS:In this study, participants (N=140) underwent a laboratory stressor and were randomly assigned to recover in one of three ways: with no phone present, with a phone present, with the HRBV game. Those in the no phone condition had no access to their phone. Those in the phone present condition had their phone but did not use it. Those in the HRVB game condition used the serious game Breather on the Happify app. Stress recovery was assessed via repeated measures of salivary alpha amylase, cortisol, and self-reported acute stress (on a 1-100 scale). RESULTS:Participants in the HRVB game condition had significantly lower levels of salivary alpha amylase during recovery than participants in the other conditions (F2,133=3.78, P=.03). There were no significant differences among the conditions during recovery for salivary cortisol levels or self-reported stress. CONCLUSIONS:These results show that engaging in a brief HRVB training session on a smartphone reduces levels of salivary alpha amylase following a stressful experience, providing preliminary evidence for the effectiveness of Breather in improving physiological stress recovery. Given the known ties between stress recovery and future well-being, this study provides a possible mechanism by which gamified biofeedback apps may lead to better health

Molecular Spiders in One Dimension

Molecular spiders are synthetic bio-molecular systems which have "legs" made of short single-stranded segments of DNA. Spiders move on a surface covered with single-stranded DNA segments complementary to legs. Different mappings are established between various models of spiders and simple exclusion processes. For spiders with simple gait and varying number of legs we compute the diffusion coefficient; when the hopping is biased we also compute their velocity.Comment: 14 pages, 2 figure

Bayesian approach to cyclic activity of CF Oct

Bayesian statistical methods of Gregory-Loredo and the Bretthorst generalization of the Lomb-Scargle periodogram have been applied for studying activity cycles of the early K-type subgiant star CF Oct. We have used a ~45 year long dataset derived from archival photographic observations, published photoelectric photometry, Hipparcos data series and All Sky Automated Survey archive. We have confirmed the already known rotational period for the star of 20.16 d and have shown evidences that it has exhibited changes from 19.90 d to 20.45 d. This is an indication for stellar surface differential rotation.The Bayesian magnitude and time--residual analysis reveals clearly at least one long-term cycle. The cycle lenght's posterior distributions appear to be multimodal with a pronounced peak at a period of 7.1 y with FWHM of 54 d for time-residuals and at a period of 9.8 y with FWHM of 184 d for magitude data. These results are consistent with the previously postulated cycle of 9+/-3 years.Comment: The paper contains 6 figures and 3 tables. Accepted for publication in Monthly Notices of the Royal Astronomical Society Main Journa

Liquid methanol Monte Carlo simulations with a refined potential which includes polarizability, nonadditivity, and intramolecular relaxation

Monte Carlo simulations of liquid methanol were performed using a refined ab initio derived potential which includes polarizability, nonadditivity, and intramolecular relaxation. The results present good agreement between the energetic and structural properties predicted by the model and those predicted by ab initio calculations of methanol clusters and experimental values of gas and condensed phases. The molecular level picture of methanol shows the existence of both rings and linear polymers in the methanol liquid phase

Increased White Matter Inflammation in Aging- and Alzheimer's Disease Brain

Chronic neuroinflammation, which is primarily mediated by microglia, plays an essential role in aging and neurodegeneration. It is still unclear whether this microglia-induced neuroinflammation occurs globally or is confined to distinct brain regions. In this study, we investigated microglia activity in various brain regions upon healthy aging and Alzheimer's disease (AD)-related pathology in both human and mouse samples. In purified microglia isolated from aging mouse brains, we found a profound gene expression pattern related to pro-inflammatory processes, phagocytosis, and lipid homeostasis. Particularly in white matter microglia of 24-month-old mice, abundant expression of phagocytic markers including Mac-2, Axl, CD16/32, Dectin1, CD11c, and CD36 was detected. Interestingly, in white matter of human brain tissue the first signs of inflammatory activity were already detected during middle age. Thus quantification of microglial proteins, such as CD68 (commonly associated with phagocytosis) and HLA-DR (associated with antigen presentation), in postmortem human white matter brain tissue showed an age-dependent increase in immunoreactivity already in middle-aged people (53.2 +/- 2.0 years). This early inflammation was also detectable by non-invasive positron emission tomography imaging using [C-11]-(R)-PK11195, a ligand that binds to activated microglia. Increased microglia activity was also prominently present in the white matter of human postmortem early-onset AD (EOAD) brain tissue. Interestingly, microglia activity in the white matter of late-onset AD (LOAD) CNS was similar to that of the aged clinically silent AD cases. These data indicate that microglia-induced neuroinflammation is predominant in the white matter of aging mice and humans as well as in EOAD brains. This white matter inflammation may contribute to the progression of neurodegeneration, and have prognostic value for detecting the onset and progression of aging and neurodegeneration