BackgroundThe short version of the World Health Organization's Quality of Life Instrument (WHOQOL-BREF) is widely validated and popularly used in assessing the subjective quality of life (QOL) of patients and the general public. We examined its psychometric properties in a large sample of community residents in mainland China.MethodsThe WHOQOL-BREF was administered to 1052 adult community residents in a major metropolitan city in southern China. The structural integrity of the 4-factor model in confirmatory factor analyses (CFA) and the relationship of QOL with demographic variables were examined. Validity was assessed using the known-group comparison (229 with vs. 823 without chronic illness), item-domain correlations, and CFA using the ML estimation in LISREL.ResultsInternal consistency reliability of the whole instrument (26 items) was 0.89, and the psychological, social, and environment domains had acceptable reliability (alpha = 0.76, 0.72, 0.78 respectively), while that of the physical domain was slightly lower (α = 0.67). The respective mean scores of these domains were 13.69, 14.11, 12.33 and 14.56. Item-domain correlations were much higher for corresponding domains than for non-corresponding domains, indicating good convergent validity. CFA provided a marginally acceptable fit to the a priori four-factor model when two matching content item pairs were allowed to be correlated; χ2 (244) = 1836, RMSEA = 0.088, NNFI = 0.898, CFI = 0.909. This factorial structure was shown to be equivalent between the participants with and without chronic illness. The differences in means between these two groups were significant but small in some domains; effect size = 0.55, 0.15, 0.18 in the physical, psychological, and social relationship domains respectively. Furthermore, males had significantly higher QOL scores than females in the psychological domain, while individuals with a younger age, higher income, and higher education levels also had significantly higher QOL. Compared with the international data, the Chinese in this study had relatively low QOL scores with about 5% of males and 16% of females being at risk for poor QOL.ConclusionsThis study has provided psychometric properties of the WHOQOL-BREF as used in China and should definitely be useful for researchers who would like to use or further refine the instrument.

Quantitative understanding the kinetics of toxic ion reactions with various heterogeneous ferrihydrite binding sites is crucial for accurately predicting the dynamic behavior of contaminants in environment. In this study, kinetics of As(V), Cr(VI), Cu(II), and Pb(II) adsorption and desorption on ferrihydrite was studied using a stirred-flow method, which showed that metal adsorption/desorption kinetics was highly dependent on the reaction conditions and varied significantly among four metals. High resolution scanning transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy showed that all four metals were distributed within the ferrihydrite aggregates homogeneously after adsorption reactions. Based on the equilibrium model CD-MUSIC, we developed a novel unified kinetics model applicable for both cation and oxyanion adsorption and desorption on ferrihydrite, which is able to account for the heterogeneity of ferrihydrite binding sites, different binding properties of cations and oxyanions, and variations of solution chemistry. The model described the kinetic results well. We quantitatively elucidated how the equilibrium properties of the cation and oxyanion binding to various ferrihydrite sites and the formation of various surface complexes controlled the adsorption and desorption kinetics at different reaction conditions and time scales. Our study provided a unified modeling method for the kinetics of ion adsorption/desorption on ferrihydrite.

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In natural environments, kinetics of As(V) sequestration/release is usually coupled with dynamic Fe mineral transformation, which is further influenced by the presence of natural organic matter (NOM). Previous work mainly focused on the interactions between As(V) and Fe minerals. However, there is a lack of both mechanistic and quantitative understanding on the coupled kinetic processes in the As(V)-Fe mineral-NOM system. In this study, we investigated the effect of humic acids (HA) on the coupled kinetics of ferrihydrite transformation into hematite/goethite and sequestration of As(V) on Fe minerals. Time-resolved As(V) and HA interactions with Fe minerals during the kinetic processes were studied using aberration-corrected scanning transmission electron microscopy, chemical extractions, stirred-flow kinetic experiments, and X-ray absorption spectroscopy. Based on the experimental results, we developed a mechanistic kinetics model for As(V) fate during Fe mineral transformation. Our results demonstrated that the rates of As(V) speciation changes within Fe minerals were coupled with ferrihydrite transformation rates, and the overall reactions were slowed down by the presence of HA that sorbed on Fe minerals. Our kinetics model is able to account for variations of Fe mineral compositions, solution chemistry, and As(V) speciation, which has significant environmental implications for predicting As(V) behavior in the environment.

Asian Pacific J Cancer Prev, 13, 2369-2378 IntroductionCervical cancer is the second most common cancer among women worldwide, with an estimated 529,000 new cases and 275,000 deaths occurring every year (Ferlay et al., 2010). Over 85% of the cases occur in developing countries like China, where it accounts for 13%