Five-year follow-up of family-based behavioral treatments for childhood obesity.

This article presents the 5-year outcome of family-based behavioral treatment of obesity for 6- to 12-year-old children in 162 families across 4 treatment outcome studies. Results suggest that treatments that use (a) conjoint targeting and reinforcement of child and parent behavior or (b) reciprocal targeting and reinforcement of children and parents are associated with the best child outcomes. Predictors of child success include self-monitoring, changing eating behavior, praise, and change in parent percent overweight. Parental outcome is predicted by self-monitoring weight, baseline parent percent overweight, and participation in fewer subsequent weight control programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender and leadership style: A meta-analysis.

Research comparing the leadership styles of women and men is reviewed, and evidence is found for both the presence and absence of differences between the sexes. In contrast to the gender-stereotypic expectation that women lead in an interpersonally oriented style and men in a task-oriented style, female and male leaders did not differ in these two styles in organizational studies. However, these aspects of leadership style were somewhat gender stereotypic in the two other classes of leadership studies investigated, namely (a) laboratory experiments and (b) assessment studies, which were defined as research that assessed the leadership styles of people not selected for occupancy of leadership roles. Consistent with stereotypic expectations about a different aspect of leadership style, the tendency to lead democratically or autocratically, women tended to adopt a more democratic or participative style and a less autocratic or directive style than did men. This sex difference appeared in all three classes of leadership studies, including those conducted in organizations. These and other findings are interpreted in terms of a social role theory of sex differences in social behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Elemental concentrations in isolated rat thymocytes prepared for cryofixation in the presence of different media

Rat thymocytes were isolated in suspension and the effect of preparing the cells for cryofixation in the presence of different media on the elemental content was investigated using the technique of X-ray microanalysis. Cells prepared in the different media showed variation in the concentrations of Na, K and Cl. The isolated cells were incubated at 310 K for 1 h to allow recovery from isolation. There was a decrease in Na and Cl content after incubation. The thymocyte population was disturbed by suspension in medium containing dextran, and this resulted in a number of cells with high concentrations of Na and low concentrations of K. These cells did not take up vital dye. Thymocytes were also prepared for freezing by using high-speed centrifugation to concentrate the cells. Thymocytes prepared by this method showed values for concentrations of Na, K and Cl similar to published values for these cells using other methods of estimation. There were, however, consistent differences in Na content between the cells prepared in Hanks' balanced salt solution and those prepared in serum. Factors which affect the apparent concentration of Na and Cl in isolated cells are discussed.     

Criterion shifts in recall.

Examined criterion shifts in recall in light of clarifications of the distinction between Type I and Type II signal detection analyses and of the concept of criterion. With a new index of the criterion, B. B. Murdock's evidence for criterion shifts in recall is found to be evidence that Ss hold their criteria constant across different retention intervals. However, with the new criterion index, criterion shifts are found in intelligibility experiments and in the short-term recall experiment by E. L. Bjork and A. F. Healy. In these studies, Ss' criteria became more lax with increasing task difficulty. A possible strategy used by the Ss is proposed to explain this finding as well as the finding that the Ss shift their criteria in Bjork and Healy's task but not in Murdock's. Finally, this analysis is applied to recall studies in which the S is allowed to leave blanks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of decreasing sedentary behavior and increasing activity on weight change in obese children.

Obese children 8–12 years old from 61 families were randomized to treatment groups that targeted increased exercise, decreased sedentary behaviors, or both (combined group) to test the influence of reinforcing children to be more active or less sedentary on child weight change. Significant decreases in percentage overweight were observed after 4 months between the sedentary and the exercise groups (–29.9 vs. –23.2). At 1 year, the sedentary group had a greater decrease in percentage overweight than did the combined and the exercise groups (–28.7 vs. –20.3 and –8.7) and greater decrease in percentage of body fat (–4.7 vs. –2.3). All groups improved fitness during treatment and follow-up. Children in the sedentary group increased their liking for high-intensity activity and reported lower caloric intake than did children in the exercise group. These results support the goal of reducing time spent in sedentary activities to improve weight loss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Time-independent mechanical and physical properties of the ternary 95.5Sn-3.9Ag-0.6Cu solder

The development of a constitutive model for predicting the thermal-mechanical fatigue (TMF) of 95.5Sn-3.9Ag-0.6Cu (wt.%) Pb-free solder interconnects requires the measurement of time-independent mechanical and physical properties. Yield stress was measured over the temperature range of −25–160°C using strain rates of 4.2 × 10⁻⁵ s⁻¹ and 8.3 × 10⁻⁴ s⁻¹. The yield-stress values ranged from approximately 40 MPa at −25°C to 10 MPa at 160°C for tests performed at 4.2 × 10⁻⁵ s⁻¹. The faster strain rate and specimen aging had a limited impact on the yield stress. The true stress/true strain curves indicated that dynamic-recovery and dynamic-recrystallization processes took place in as-cast samples exposed to temperatures of 125°C and 160°C, respectively, while tested at a strain rate of 4.2 × 10⁻⁵ s⁻¹. Aging the sample prior to testing, as well as a faster strain rate, mitigated both phenomena. Dynamic Young’s modulus values ranged from 55 GPa at −50°C to 35 GPa at 200°C, while the coefficient of thermal expansion (CTE) increased from approximately 12 × 10⁻⁶°C⁻¹ to 24 × 10⁻⁶°C⁻¹ for the same temperature range. The aging treatment had little effect on either Young’s modulus or the CTE.     

On the cognitive structure of basic arithmetic skills: Operation, order, and symbol transfer effects.

In 2 experiments, 24 college students practiced extensively on single-digit multiplication and division problems (e.g.,?=?6?×?9; 42?×?6) and were tested on both practice problems and several altered versions of those problems, which were constructed by changing the required operation, operand order, or arithmetic symbol. There was strong positive transfer to test problems that had exactly the same elements (the numbers and the required operation) as a practice problem, regardless of whether other factors such as operand order or symbol were changed, but little if any positive transfer to test problems that did not have the same elements as a practice problem. An identical elements framework is used to interpret these results and implications for existing computational models of arithmetic fact retrieval and for the development of arithmetic skill are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

EXPECTATION-MAXIMIZATION ALGORITHMS AND THE ESTIMATION OF TIME SERIES MODELS IN THE PRESENCE OF OUTLIERS

Abstract. The expectation-maximization algorithm is reviewed briefly. The algorithm is applied to time series situations where outliers may be present. An approximation of the algorithm is considered to reduce the computational complexity. Examples are given to illustrate the application of this algorithm.     

Maternal drug use during pregnancy: Are preterm and full-term infants affected differently?

This study examined whether preterm infants are more vulnerable to the effects of prenatal drug exposure than are full-term infants. The sample of 235 low-income African American mothers and their infants included 119 cocaine-polydrug users, 19 alcohol-only users, and 97 nonusers; 148 infants were full term and 87 were preterm. Direct effects of exposure on birth weight, birth length, ponderal index, and irritability were moderated by length of gestation: Fetal growth deficits were more extreme in later-born infants, whereas increases in irritability were more extreme in earlier born infants. Effects of exposure on cardiorespiratory reactivity to a neonatal exam were not moderated by length of gestation. In general, effects of exposure occurred for both cocaine-polydrug and alcohol-only users and so could not be unambiguously attributed to either of these drugs alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ten-year outcomes of behavioral family-based treatment for childhood obesity.

Reports 10-yr treatment outcomes for obese children in 4 randomized treatment studies. At 10 yrs, 34% decreased percentage overweight by 20% or more, and 30% were not obese. Significant effects were observed when parents and children were targeted and reinforced for weight loss in comparison with nontargeted controls and for children given lifestyle or aerobic exercise in comparison with a calisthenics control. 34% of the variance in change in percentage overweight was predicted from sex, baseline percentage overweight, self-monitoring weight, meals eaten at home, and family and friends' support for eating and exercise. Results show long-term changes in children depend on the treatment, and evidence converges on the importance of the family and other sources of support for eating and activity change. (PsycINFO Database Record (c) 2010 APA, all rights reserved)