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Though the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) was introduced into China more than 60 years ago, the genetic diversity and structure of this exotic insect pest and virus vector have not been studied. To investigate the population genetic characteristics of this invasive species and to identify potential invasion routes, the genetic diversity and population structure of 17 collections of T. vaporariorum from nine provinces in China were analyzed using seven microsatellite loci. The results of the analyses indicated that the genetic diversity for the populations examined from the four provinces: Jilin, Ningxia, Guizhou and Qinghai, was lower than the genetic diversity of populations from the five provinces: Yunnan, Shandong, Shanxi, Liaoning, and Gansu. The T. vaporariorum populations analyzed in this study grouped as two distinct genetic clusters based on the analysis using STRUCTURE, whereas, 8 clusters were identified based on the BAPS analysis. Of the 136 genetic distance (Fst) values, 128 (94%) were associated with a significant exact test. There was a significant relationship between Fst and geographical distance. These results demonstrate that populations of T. vaporariorum in China exhibit significant genetic differentiation, indicating the likelihood that multiple introductions of T. vaporariorum into China have occurred. Also, the populations collected from the provinces of Jilin, Ningxia, Guizhou and Qinghai appear to represent secondary introductions originating from other Chinese provinces. [ABSTRACT FROM AUTHOR]

The relationships between ambient PM2.5 and PM10 and arrhythmia and the effect modification by cigarette smoking were investigated. Data from U.S. Environmental Protection Agency (EPA) air quality monitors and an established national-scale, log-normal kriging method were used to spatially estimate daily mean concentrations of PM at addresses of 57,422 individuals from 59 examination sites in 24 U.S. states in 1999-2004. The acute and subacute exposures were estimated as mean, geocoded address-specific PM concentrations on the day of, 0-2 d before, and averaged over 30 d before the electrocardiogram (ECG) (Lag0; Lag1; Lag2; Lag1-30). At the time of standard 12-lead resting ECG, the mean age (SD) of participants was 67.5 (6.9) yr (84% non-Hispanic White; 6% current smoker; 15% with coronary heart disease; 5% with ectopy). After the identification of significant effect modifiers, two-stage random-effects models were used to calculate center-pooled odds ratios and 95% confidence intervals (OR, 95% CI) of arrhythmia per 10 μg/m3 increase in PM concentrations. Among current smokers, Lag0 and Lag1 PM concentrations were significantly associated ventricular ectopy (VE)—the OR (95% CI) for VE among current smokers was 2 (1.32-3.3) and 1.32 (1.07-1.65) at Lag1 PM2.5 and PM10, respectively. The interactions between current smoking and acute exposures (Lag0; Lag1; Lag2) were significant in relationship to VE. Acute exposures were not significantly associated with supraventricular ectopy (SVE), or with VE among nonsmokers. Subacute (Lag1-30) exposures were not significantly associated with arrhythmia. Acute PM2.5 and PM10 exposure is directly associated with the odds of VE among smokers, suggesting that they are more vulnerable to the arrhythmogenic effects of PM. [ABSTRACT FROM AUTHOR]

This paper critically debates the current development of parental prosecution for students'; unauthorized absence from school. The author examines the history of compulsory education in Europe and the USA and questions its pertinence today. The results of a survey of prosecution and truancy during the period 1999–2002, conducted in forty-three LEAs in England and Wales, are presented. The findings question the effectiveness of such new legislation and practice. [ABSTRACT FROM AUTHOR]

The article focuses on the U.S.-China-Japan triangle. This triangle has been formed from behavioral pattern and bilateral relations of these countries. The triangular relationships will possibly lead to more transparency and cooperative dealings, hostile relationships and loosening into multilateral and complex framework. The perceptions of the U.S. regarding these crucial factor is within the emerging of China as the world power, as well as the belief that the strong triad of the U.S.-China-Japan can create a more stable relations in Asia-Pacific.