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A fast approximation to the Boys functions (related to the lower incomplete gamma function of half-integer parameter) by a single closed-form analytical expression for all argument values have been developed and tested. Besides the exponential function needed anyway for downward recursion, it uses a small number of addition, multiplication, division, and square root operations, and thus is straightforward to vectorize.

Recent evidence has suggested that aggressive boys demonstrate a bias toward attributing hostility to peers in unwarranted circumstances. This study explored two aspects of cognitive processing that might be related to attributional bias: speed of decision making and selective recall of hostile cues. Groups of aggressive and nonaggressive boys at three age levels participated in a detective game in which the task was to accumulate evidence in order to decide whether or not a peer had acted with benevolence or hostility. Aggressive boys were found to respond more quickly and with less attention to available social cues than nonaggressive boys. Aggressive boys also overattributed hostility to peers in unwarranted circumstances, but only when they responded quickly. This restriction suggested that training aggressive boys to respond more slowly could lead to fewer biased attributions on their part. Selective recall was also related to biased attributions, for both groups of boys. This suggested that training boys to recall all cues nonselectively could reduce the frequency of their biased attributions. The results are discussed in terms of a cognitive model of aggressive behavior. Because of the correlational nature of this study, the conclusions are stated as tentative. Recently, researchers have suggested that biases in children's social perceptions may act as mediators of deviant interpersonal aggressive behavior. Nasby, Hayden, and DePaulo (1980), for example, found that institutionalized aggressive boys display an attributional bias toward interpreting social cues from others as displays of hostility, even when the cues were meant to be benign. Similarly, Dodge (1980) found that in reaction to an ambiguously intended frustrating event, aggressive boys responded behaviorally as if the peer instigator had malevolently intended the act, whereas nonaggressive boys responded as if the peer had acted benignly. In a second study, Dodge also found that aggressive boys were more likely to attribute hostility to peers in ambiguous situations than nonaggressive boys were. The importance of this attributional bias in understanding interpersonal behavior is reflected in the work of Kelley and Stahelski (1970), who demonstrated in a different context that such attributional biases could lead to interpersonal conflicts that perpetuate the biased judgments. Support for this research was provided by a grant from the Spencer Foundation. The authors would like to acknowledge the support of administrators and teachers of the Monroe County Community School Corporation and the individual contributions of Cynthia Frame, Bryan Burke, and Scott Robbins.

BACKGROUND: Increasing evidence suggests a close association between early sexual maturation (SM) and obesity in girls and female adults. Earlier maturing girls are more likely to be obese than nonearly maturers. However, limited research has been conducted in boys. OBJECTIVE: To examine the influence of early SM on fatness in boys and compare it with girls, and to test the hypothesis that the associations differ by gender because of the differences in growth and SM patterns in boys and girls. STUDY DESIGN: Cross-sectional study. SUBJECTS: One thousand five hundred one girls and 1520 boys (aged 8-14 years) who participated in the Third National Health and Nutrition Examination Survey survey (1988-1994) and had complete anthropometry (weight, height, skinfold thickness) and SM data. METHODS: Based on each individual's age and SM status (Tanner stages: genitalia stages for boys and breast stages for girls), the subjects were classified as: 1) early maturers (those who reached a certain Tanner stage earlier than the median age for that stage), and 2) the others (average and later maturers). Overweight was defined as a body mass index (BMI) > or =85th percentile, and obesity > or =95th percentile. Logistic regression analysis was to test how early maturation affected the risks for overweight and obese. Using multiple linear regression models, the associations between fatness (BMI and skinfold thickness) and SM were systematically examined. Covariates including age, ethnicity, residence, family income, energy intake, and physical activity were adjusted. RESULTS: Early SM was positively associated with overweight and obesity in girls, but the associations were reverse for boys. The prevalence of overweight in early maturers versus the others was 22.6% versus 31.6% in boys and 34.4% versus 23.2% in girls; the figures for obesity were 6.7% versus 14.8% and 15.6% versus 8.1%, respectively. Odd ratios and 95% confidence intervals for obesity were 0.4 (0.2, 0.8) for boys and 2.0 (1.1, 3.5) for girls, and covariates were adjusted. Most significant differences in overweight and obesity among ethnic groups disappeared after controlling for SM. Fatness (BMI and skinfold thickness) was associated with SM stages and with early maturation in boys and girls, but the associations were in opposite directions. Compared with their counterparts, early maturing boys were thinner, whereas early maturing girls were fatter. CONCLUSIONS: Obesity is associated with sexual maturation in both boys and girls, but the association differs. There is positive association in girls, but a negative one in boys. Maturation status should be taken into consideration when assessing child and adolescent obesity.

Purpose: This study aims to analyze and compare selected physical fitness, physiological, and psychological variables among boys from government, government- aided, and private schools in the Chennai district. The purpose is to understand how different school environments impact these variables and to provide insights that can inform policy and practice in physical education and health promotion.  Methodology: A sample of 300 boys aged 12-15 years was selected through stratified random sampling, with 100 boys from each school type (government, government-aided, and private schools). Physical fitness was measured using the Fitness Gram test battery, physiological variables such as BMI, resting heart rate, and blood pressure were assessed using standard clinical procedures, and psychological variables were evaluated using the Rosenberg Self- Esteem Scale and the Perceived Stress Scale. Data were analyzed using ANOVA to compare the means across the three school types, with post-hoc tests conducted to identify specific group differences.  Conclusion: The study found significant differences in physical fitness, physiological health, and psychological well-being among boys from different types of schools. Boys from private schools exhibited better physical fitness and lower stress levels compared to their peers in government and government-aided schools. These findings highlight the influence of socio-economic factors and access to resources on students' health and suggest the need for targeted interventions in government and government- aided schools to improve physical and psychological well- being among students.

Mixed longitudinal data on the physical changes at puberty in 228 normal boys are presented together with normal standards for stages of genital and pubic hair development. The genitalia began to develop between the ages 9½ years and 13½ years in 95% of boys (mean = 11.6 ± 0.09) and reached maturity at ages varying between 13 and 17 (mean = 14.9 ± 1.10). The age at which pubic hair first appeared was not accurately determined, but its development through the later stages was studied. It reached the equivalent of an adult female distribution at a mean age of 15.2 ± 0.01 years. On average the genitalia reached the adult stage 3.0 years after they first began to develop; but some boys completed this development in as little as 1.8 years while others took as much as 4.7 years. Some boys complete the whole process in less time than others take to go from Stage G2 to Stage G3. The genitalia begin to develop before pubic hair is visible in photographs in practically all boys. The 41 boys in whom it could be studied reached their maximum rate of growth (peak height velocity) at a mean age of 14.1 ± 0.14 years. Very few boys (about 5%) reached peak height velocity before their genitalia were in Stage 4 and over 20% did not do so until their genitalia were adult. Peak height velocity is reached, on the average, nearly 2 years later in boys than in girls, but the boys9 genitalia begin to develop only about 6 months later than the girls9 breasts. Pubic hair appears about 1½ years later in boys than in girls.

We present a new fast algorithm for computing the Boys function using a nonlinear approximation of the integrand via exponentials. The resulting algorithms evaluate the Boys function with real and complex valued arguments and are competitive with previously developed algorithms for the same purpose.

COIE, JOHN D., and KUPERSMIDT, JANIS B. A Behavioral Analysis of Emerging Social Status in Boys' Groups. CHILD DEVELOPMENT, 1983, 54, 1400-1416. 4 fourth-grade boys, each different social status types-rejected, popular, neglected, and average--met in play groups once a week for 6 weeks. 5 groups were of boys from the same classroom, and 5 of the boys were from 4 different schools. Within 3 sessions, social status in the groups was highly correlated with school-based status for boys from both familiar and unfamiliar groups. Observations of behavior coded from videotapes revealed significant distinctive patterns of social interaction for the social status types. Rejected boys were extremely active and aversive, but no more physically aversive than average boys, although group members perceived rejected boys as starting fights. Popular boys engaged in more norm setting and were more prosocial in the unfamiliar groups. Although neglected boys were the least interactive and aversive, they were more visible and active in the unfamiliar group and seemed most affected by the new social context. The findings underscore the importance of distinguishing between behaviors associated with the emergence of social status in contrast to those associated with the maintenance of social status.

Based on the crystal structures of the previously proposed low energy phosphorene allotropes η-P and θ-P (Nano. Lett. 2015, 15, 3557), we propose five new structural stable phosphorene boys (XX-XY or XY-XY) and girls (XX-XX) through gene (XY from η-P and XX from θ-P) recombination methods. All of these five new phosphorene allotropes are obviously different from their parents, showing very different and fascinating two-dimensional patterns between each other. The dynamical stabilities of these phosphorene allotropes are confirmed positive and some of them are confirmed energetically more favorable than their parents (η-P and θ-P). Especially, the XX-XX type girl G1-P is confirmed energetically more favorable than all the previously proposed phosphorene allotropes, including black phosphorene (α-P, ACS Nano, 2014, 8, 4033) and blue phosphorene (β-P, Phys. Rev. Lett. 2014, 112, 176802), which is expected to be synthesized in future experiment through vapor deposition. Our results show that such a new promising phosphorene allotrope G1-P is an excellent candidate for potential applications in nano-electronics according to its middle band gap about 1.58 eV from DFT-HSE06 calculation.

BACKGROUND: Effective ways to prevent arthropathy in severe hemophilia are unknown. METHODS: We randomly assigned young boys with severe hemophilia A to regular infusions of recombinant factor VIII (prophylaxis) or to an enhanced episodic infusion schedule of at least three doses totaling a minimum of 80 IU of factor VIII per kilogram of body weight at the time of a joint hemorrhage. The primary outcome was the incidence of bone or cartilage damage as detected in index joints (ankles, knees, and elbows) by radiography or magnetic resonance imaging (MRI). RESULTS: Sixty-five boys younger than 30 months of age were randomly assigned to prophylaxis (32 boys) or enhanced episodic therapy (33 boys). When the boys reached 6 years of age, 93% of those in the prophylaxis group and 55% of those in the episodic-therapy group were considered to have normal index-joint structure on MRI (P=0.006). The relative risk of MRI-detected joint damage with episodic therapy as compared with prophylaxis was 6.1 (95% confidence interval, 1.5 to 24.4). The mean annual numbers of joint and total hemorrhages were higher at study exit in the episodic-therapy group than in the prophylaxis group (P<0.001 for both comparisons). High titers of inhibitors of factor VIII developed in two boys who received prophylaxis; three boys in the episodic-therapy group had a life-threatening hemorrhage. Hospitalizations and infections associated with central-catheter placement did not differ significantly between the two groups. CONCLUSIONS: Prophylaxis with recombinant factor VIII can prevent joint damage and decrease the frequency of joint and other hemorrhages in young boys with severe hemophilia A. (ClinicalTrials.gov number, NCT00207597 [ClinicalTrials.gov].).