Identifying Shared Environmental Contributions to Early Substance Use: The Respective Roles of Peers and Parents.

Although behavior genetic studies have suggested that early substance use is primarily environmentally mediated, no study has sought to identify the specific sources of environmental variance. Using data obtained from multiple informants, this study assessed the contributions of peer deviance and parent-child relationship problems to substance use in 14-year-old male and female twins (N = 1,403) drawn from the Minnesota Twin Family Study (MTFS). All three phenotypes were influenced primarily by shared environmental variance (average c2 = .51), as was the overlap among them. Moreover, peer deviance and parent-child relationship problems accounted for approximately 77% of the variance in early substance use. Findings also indicated that peer deviance, but not parent-child relationship problems, accounted uniquely for variance in early substance use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Transfer of low nanoliter volumes between microplates using focused acoustics—automation considerations

Acoustic droplet ejection (ADE) gently and precisely aliquots nanoliter and picoliter liquid volumes without any physical contact with the solution being transferred. The technology is very automation-friendly, as it is compatible with conventional microplates. Focused energy from an acoustic transducer induces droplet ejection into an inverted standard microplate. The commercial system transfers low-nanoliter volumes of dimethyl sulfoxide–dissolved compound libraries and thereby enables cell-based assays to be performed in 1536-well plates.     

Technical Issues for Lunar Base Structures

The establishment of a permanent human presence on other planets will require establishing permanent infrastructure in new environments. Civil engineers select, define, and implement solutions to infrastructure design problems in unique environmental contexts. Wind and seismic loading are two examples of constraints long familiar to terrestrial civil engineering. Designing structures for lunar exploration, development and eventual settlement will make use of the same design processes already practiced by the civil engineering profession. However, the extensive experience base resulting from centuries of terrestrial work does not adequately prepare civil engineers for the unprecedented constraints and environmental conditions that are encountered in space. The limited knowledge we already have about the Moon (mostly from the Apollo program) is a place to start. By assimilating and working with this knowledge, those pursuing the design of lunar base structures can begin to produce realistic and valid design solutions. The paper presents technical, operations, and programmatic issues that the writers consider fundamental to understanding the facts of life in this promising new design arena.     

Generating Future Land-Use and Transportation Plans for High-Growth Cities Using a Genetic Algorithm

Abstract:   An elitist genetic algorithm was used to find a diverse non-dominated set of optimal future zoning and street plans for two high-growth cities in the United States of America. Plans were judged with regard to housing capacity, employment capacity, greenspace, traffic congestion, and change from the status quo. A multiobjective fitness function was used. The genetic algorithm offers the possibility of efficiently searching over tens of thousands of plans for a trade-off set of non-dominated plans. The trade-off set ranged from a minimum change plan, where undeveloped farmland was rezoned as commercial or residential land, to a minimum traffic congestion plan where commercial and residential usage were spread throughout the cities rather than concentrated in one or two areas. The algorithm is general enough to be applied to other cities and metropolitan regions.     

Social support and the effectiveness of group therapy.

Collected self-report data from 37 pretest clients and 26 of the same clients at posttest who participated in 6 counseling center therapy groups. Questionnaires assessed 6 functionally different types of social support provided from 2 sources, therapy group members vs persons outside the group, together with pre- and posttest levels of 3 distress symptoms, which were depression, self-esteem, and psychological symptoms of stress. Significant improvement in symptoms was noted during the 8-wk interventions, and this improvement was related to the availability of social support, depending on the type and source of support. In general, support from sources outside the therapy group appeared to have the most impact. Levels of certain types of support differed in groups depending on whether or not the group was composed of members with a common presenting concern. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Load testing, structural reliability and test evaluation

A brief review of the history and types of load testing is followed by an examination of the effects of load test and other information on structural reliability. Two aspects are studied. (1) Multi-mode proof testing is posed as a system relability problem with one or more inequality conditions on structural performance. After-test reliability can then be found using standard system reliability methods from the reliability of the system augmented in “series” with the test mode, divided by the reliability in the test mode alone. (2) Test evaluation procedures for several applications are analysed using simulation of destructive sample tests, including strength uncertainty discoverable by testing and other non-test uncertainties in strength and loading. Evaluation rules are found to have a significant effect on the achieved reliability of test-based design.     

Recognizing National Hockey League greatness with an ignorance-based heuristic.

This study examined whether people adhered to the recognition heuristic (i.e., inferred that a recognized hockey player had more total career points than an unrecognized player) and whether using this heuristic could yield accurate decisions. On paired comparisons, having participants report whether they recognized each player plus any knowledge they had about each player permitted players to be classified as either unrecognized (UR), merely recognized (MR), or recognized with additional knowledge (RK), thus producing six possible trial types. Participants adhered to the recognition heuristic on 95% of MR-UR trials and were accurate on 81% of those trials. They chose the recognized player on 98% of RK-UR trials, yielding 94% accuracy. Women had less knowledge and recognized fewer players than men, yet they were nearly as accurate as men. Future research should examine the conditions under which the recognition heuristic is an adaptive strategy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Co-occurrence of eating disorders and incest: The role of attachment, family environment, and social competencies.

Childhood attachment, family environment, and adult social competencies were examined to explain the association between sexual abuse and eating disorders (EDs). Female college students (n?=?102) and female clients sexually abused in childhood (n?=?52) completed surveys retrospectively that assessed parental bonds, family environment, and sexual abuse, as well as current self-efficacy, social support, intimacy, adult attachment style, and ED symptoms. Client incest survivors had a higher ED rate (47%) than did sexually abused clients (22%), student incest survivors (24%), or nonabused students (17%). Significant associations were found between family environment, incest, social competencies, and eating disorders. Incest survivors had more dysfunctional families and lower social competencies than did nonabused women. Among incest survivors, those with the lowest levels of social competencies and poorest bonds with their mothers had more ED symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lateralization of High Frequency Sounds as a Function of Interaural Amplitude Disparity.

Twenty-five subjects made graphic ratings of the perceived lateral position within the head of sounds presented through headphones. The stimuli were high frequency, pure tones and amplitude modulated sounds. For the amplitude modulated sounds, a 200 Hz modulation frequency was combined with carrier frequencies of 2200 Hz, 3200 Hz, 4200 Hz, and 5200 Hz, which were also the pure tone frequencies. Interaural level differences in the signals ranged from zero to 12 dB. The rate of lateralization was defined as the slope of the linear trend relating laterality ratings to interaural level differences. The rate of lateralization was found to be a decreasing function of frequency. The laterality ratings of amplitude modulated signals were nearly identical to those for pure tones. This result suggests that, for high frequency signals, conflicting temporal information that a source is centered is suppressed in favor of information from level differences that the source is off-center. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Choosing between a rock and a hard place when data are scarce and the questions important: Reply to Hollenbeck, DeRue, and Mannor (2006).

This article replies to J. R. Hollenbeck, D. S. DeRue, and M. Mannor's comment (see record 2006-00819-001) critiquing R. S. Peterson, D. B. Smith, P. V. Martorana, and P. D. Owens's use (see record 2003-08045-002) of a large number of statistical tests in research with a small sample. Although Hollenbeck et al's point of view is valid, it paints a one-sided picture of the trade-offs inherent in empirical research when data are scarce and the questions important. This reply specifically discusses the dilemmas Peterson et al faced in conducting empirical research in a nascent area and suggests that theory development in such a situation can be well served by studies that use alternative or new methods with small samples. Theory development scholarship using small-sample research methods (e.g., case studies and Q sorting from archival sources) can be useful for stimulating ideas, theory, and research programs that can be tested with large-sample quantitative research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)