Measurement analysis of two radials with a common-origin point and its application.

In spectral analysis, a chemical component is usually identified by its characteristic spectra, especially the peaks. If two components have overlapping spectral peaks, they are generally considered to be indiscriminate in current analytical chemistry textbooks and related literature. However, if the intensities of the overlapping major spectral peaks are additive, and have different rates of change with respect to variations in the concentration of the individual components, a simple method, named the 'common-origin ray', for the simultaneous determination of two components can be established. Several case studies highlighting its applications are presented.

Determination of amino acid nitrogen in tuber mustard using near-infrared spectroscopy with waveband selection stability.

Near-infrared (NIR) spectroscopy was successfully applied to the rapid chemical-free determination of amino acid nitrogen (AAN) in tuber mustard. Moving window partial least squares, combined with Savitzky-Golay smoothing, was used for the waveband selection. Based on the various divisions in the calibration and prediction sets, an effective modeling approach with good stability was proposed. The results confirmed that the long-wave NIR region contains sufficient information for the quantification of AAN in tuber mustard. An appropriate waveband (5874-4,258 cm(-1)) located in the combination region of NIR was selected. The validation root mean square error of prediction and the validation correlation coefficients of prediction were 0.380 mg/g and 0.962, respectively, both indicating good validation effect and stability. The results provided a reliable NIR model and can serve as valuable references for designing spectroscopic instruments for quality evaluation of tuber mustard.

Stigma against HIV-infected persons among migrant women living in Shanghai, China.

We examined the characteristics of 601 female migrants in Shanghai regarding stigmatizing attitudes toward people living with HIV/AIDS (PLWHA). A community-based cross-sectional study was conducted July and August 2008, using an anonymous questionnaire. Most participants (88%) were married, 9.2% reported multiple sexual partners, 19.1% knew about voluntary counseling and testing clinics, and 3.7% had been tested for HIV. About half (56.4%) agreed that people who acquire HIV/AIDS through sex or drug use deserve it. About 80% admitted that they were afraid of PLWHA. Low knowledge of HIV/AIDS, being older, low levels of education, and longer duration in Shanghai were correlates for having stigmatizing attitudes, while having premarital sex and/or multiple sex partners correlated with less stigma. HIV-related stigma among female migrants in Shanghai is common. Future stigma reduction prevention and intervention programs among female migrants should target those who are older, less educated, and have lived in Shanghai relatively longer.