Comparisons of normalization methods for relative quantitative in real-time polymerase chain reaction

The real-time polymerase chain reaction (rtPCR) provides sensitive and accurate quantitative results and becomes a widespread technique in analyzing gene expressions. House-keeping genes are required as references to normalize data of target genes, which may be unstable. This normalization process is similar to the normalization in analyzing high-density oligonucleotide arrays. This article evaluates the feasibility of normalizations for high-density oligonucleotide arrays to normalize data collected in rtPCR experiments. Since data features are different, simulations are used to evaluate the performance of these normalizations to rtPCR data based on five indices. Their feasibilities are illustrated by a rtPCR data.     

When does multitasking facilitate information processing? Effects of Internet-based multitasking on information seeking and information gain

This study examined whether Internet-based multitasking facilitates information gain by allowing users to seek additional information online. Study 1, using survey data, suggested that TV-Internet multitasking increased information gain, whereas TV-print media multitasking reduced it. In addition, online information seeking mediated the effect of TV-Internet multitasking on information gain. Study 2, using experimental data, confirmed the differential effects of TV-Internet multitasking and TV-print multitasking on information gain. The theoretical and practical implications of these findings are further discussed.     

The elephant in the room is awake and takes things personally: The North Korean nuclear threat and the general public's estimation of American diplomacy

The general audience for a global crisis can become a grassroots force in the ultimate fate of policy decisions. Focusing on the North Korean nuclear crisis case, certain contingent factors (dominant coalition characteristics, external threat, and external public characteristics) were overall strong predictors for public estimation about the government stance. Further, perception of situational factors (external threat and external public characteristics) was a stronger predictor for the participants’ stance estimation than perception of predisposing factors (dominant coalition characteristics). Implications for international diplomacy were discussed.     

Precursors and pathways to adolescent prostitution in taiwan

This paper identifies the major precursors and pathways to prostitution for contemporary Taiwanese girls and the socio‐economic and cultural changes that have facilitated the shift in pathways over the past 10 years. Special attention is paid to the case of Taiwanese aborigines, who have particularly suffered systemic disruption due to prostitution. Analysis of case files and interviews provide quantitative and qualitative data that highlight the role of filial piety and the shift from indenture to runaway as the major pathway in Taiwan. Discussion includes relation of these findings to juvenile entry into prostitution in other countries, directions for future research, and policy recommendations for Taiwan's government.     

Relocation Stress, Coping, and Sense of Control Among Resettlers Resulting from China’s Three Gorges Dam Project

The involuntary relocation of people for development purposes has become prevalent across the world in recent decades. Depression is one of the documented negative outcomes of involuntary relocation among resettlers. Viewing the affected population simply as passive victims, past studies have largely ignored the coping strategies employed by individual resettlers in dealing with stress they experienced in the relocation process. Focusing on Three Gorges Project-induced relocation in China, this study examines coping strategies employed by resettlers using panel data collected before and after relocation. We found that emotion-focused coping was more effective than problem-focused coping in combating relocation-related depression. Unsuccessful problem-focused coping was found to elevate, rather than reduce depression. Emotion-focused coping reduces depression not only directly but also indirectly by restoring resettlers’ sense of control. This study contributes to the literature by identifying coping strategies, as well as their mechanisms, that are effective in combating relocation-induced distress.     

Improved construction for pooling design

Pooling design is a mathematical tool with many applications in molecular biology, specially to reduce the number of tests for DNA library screening. In this note, we study construction of pooling design and present an improvement to a recent new construction given by Du et al. (J. Comput. Biol. 13:990–995, 2006). P. Deng and W. Wu supported in part by National Science Foundation under grants CCF-0514796 and CNS-0524429. T. Znati supported in part by National Science Foundation under grant CCF-0548895.     

Exploratory analysis of verbal aggression in romantic relationships among unmarried men and women: Predictive patterns by gender and race

This is an exploratory study that examined verbal aggression in romantic relationships among unmarried Black and White women and men as a function of gender and race. We employed an ecological approach to examine the receipt of verbal aggression separately for men and women at the levels of individual, relationship, and community. We also explored whether gender-specific correlates of verbal aggression interacted with race. Analyses were based on a sample of 212 women and 133 men in non-marital romantic relationships recruited from 21 U.S. cities for a larger study. Linear mixed-effects models revealed that factors related to experiencing verbal aggression differed substantially for unmarried women and men in romantic relationships. Interesting racial differences also emerged distinctly for women and men.     

An Evaluation of Risk Estimation Procedures for Mixtures of Carcinogens

The estimation of health risks from exposure to a mixture of chemical carcinogens is generally based on the combination of information from several available single compound studies. The current practice of directly summing the upper bound risk estimates of individual carcinogenic components as an upper bound on the total risk of a mixture is known to be generally too conservative. Gaylor and Chen (1996, Risk Analysis) proposed a simple procedure to compute an upper bound on the total risk using only the upper confidence limits and central risk estimates of individual carcinogens. The Gaylor-Chen procedure was derived based on an underlying assumption of the normality for the distributions of individual risk estimates. In this paper we evaluated the Gaylor-Chen approach in terms of the coverage probability. The performance of the Gaylor-Chen approach in terms the coverages of the upper confidence limits on the true risks of individual carcinogens. In general, if the coverage probabilities for the individual carcinogens are all approximately equal to the nominal level, then the Gaylor-Chen approach should perform well. However, the Gaylor-Chen approach can be conservative or anti-conservative if some or all individual upper confidence limit estimates are conservative or anti-conservative.     

Satisfaction Ratings of QOLPAV: Psychometric Properties Based on the Graded Response Model

A scale measuring quality of life (QOL) is important in adolescent research. Using the graded response model (GRM), this study evaluates the psychometric properties of the satisfaction ratings of the Quality of Life Profile Adolescent Version (QOLPAV). Data for 1,392 adolescents were used to check IRT assumptions such as unidimensionality and local item dependence (LID). The goodness of fit of the GRM to the data and the item characteristic curves were evaluated. The reliability and validity analyses included item/test information, Cronbach’s α, and convergent and discriminant validity. Differential item functioning (DIF) procedures were also performed to detect item bias. The results provide evidence that the items sufficiently measured one single dimension. Few pairs of questions were flagged as LID due to content or wording similarity. Five items did not fit the GRM, and 4 were low in item discrimination. The findings also suggest that the assessment had appropriate reliability and validity. The DIF impact on the assessment score was considered minor. Because QOLPAV includes a respondent’s perceived importance of various life aspects, a short form that only considers important life aspects in the overall QOL estimation for each respondent becomes feasible within the framework of IRT. Future studies focusing on the development of a QOL overall index using the items from QOLPAV are recommended.