Using the WHO Self-Reporting Questionnaire-20 (SRQ-20) to Detect Symptoms of Common Mental Disorders among Pregnant Women in Vietnam: a Validation Study.

Purpose: Detection of antenatal common mental disorders in low-resource settings like Vietnam is important and requires a reliable, valid and practical screening tool. Currently, there is no such tool validated for use among pregnant women in Vietnam. This study aims to assess the validity of the Vietnamese version of the 20-item Self Reporting Questionnaire (SRQ-20) by evaluating its reliability, factorial structure, and performance in detecting common mental disorder (CMD) symptoms, thereby identifying the optimum cut-off score for CMD screening among pregnant women in Vietnam. Participants and Methods: A total of 210 pregnant women from four rural communes participated in a face-to-face interview using the Vietnamese version of the SRQ-20, followed by a clinical diagnostic interview based on ICD-10 diagnostic criteria of CMDs. The reliability of the SRQ-20 was assessed by calculating the scale's Cronbach's alpha to measure internal consistency. Factor analyses were undertaken to examine the factor structure of the instrument. The Receiver Operating Characteristic (ROC) curve analysis was performed to assess the performance of the SRQ-20 against the clinical diagnosis and to identify the optimum cut-off score. Results: Internal consistency was good, with a Cronbach's alpha of 0.87. Factor analyses resulted in a 4-factor solution. The area under the ROC curve (AUC) for detection of CMDs was 0.90. The optimum cut-off score of the SRQ-20 for detection of CMD symptoms among Vietnamese pregnant women was 5/6. Conclusion: The Vietnamese version of the SRQ-20 has the capacity to detect CMDs among pregnant women effectively and is recommended for use as a screening tool for CMDs in antenatal care settings in Vietnam.

Binder Selection to Modify Hydrocarbon Cracking Properties of Zeolite-Containing Composites.

Activity, selectivity, and deactivation behavior of catalyst materials determine their efficiency in hydrocarbon conversion processes. For hydrocarbon cracking, the industrial catalyst is an important parameter in reaction technology to produce valuable compounds, e.g., light olefins (C3-C5) and gasoline from crude oil fractions with high molecular weight (C16+). One strategy to enhance the catalytic activity for precracking is increasing the matrix activity, which depends on the used binder and additives. In this work, three binders (water glass, aluminum chloride, and a mixture of colloidal silica with aluminum dihydrogen phosphate) were used in combination with active zeolite Y, kaolin as filler, and ZSM-5 as additive to produce composite materials. Specific surface area and surface acidity measurements were combined with catalytic testing of the formulated samples in order to find the relation between the catalyst morphology and its activity. In addition, constraint index was used as a control parameter for the determination of the shape-selective properties and their correlation with the catalytic activity. The results show that the binders determine the porosity of the matrix and so the accessibility to zeolite pores and active sites. Matrixes with low porosity and activity enhance coke production and deactivate faster than matrixes with mesopores. Furthermore, ZSM-5 modifies the individual morphological and catalytic effects of the binders. Everything considered, the small crystals of ZSM-5 together with mesopores increase the olefins yield, reduce coking, and therefore enhance the performance of the final grain.