Three different kinds of plastic bags HL, VHL, and VN1 with different chemical nature were degraded by a novel thermophilic bacterial strain isolated from composting agricultural residual in Vietnam in shaking liquid medium at 55 °C after 30 d. The new strain was classified in the Bacillus genus by morphological property and sequence of partial 16Sr RNA coding gene and named as Bacillus sp. BCBT21. This strain could produce extracellular hydrolase enzymes including lipase, CMCase, xylanase, chitinase, and protease with different level of activity in the same media. After a 30-d treatment at 55 °C with Bacillus sp. BCBT21, all characteristics including properties and morphology of treated plastic bags had been significantly changed. The weight loss, structure and surface morphology of these bags as well as the change in the average molecular weight of VHL bag were detected. Especially, the average molecular weight of VHL bag was significantly reduced from 205 000 to 116 760. New metabolites from the treated bags indicated biodegradation occurring with the different pathways. This finding suggests that there is high potential to develop an effective integrated method for plastic bags degradation by a combination of extracellular enzymes from bacteria and fungi existing in the composting process.

Background This study evaluated the psychometric properties of three self-reported scales including WHO Well-Being Index (WHO-5), Patient Health Questionnaire-9 items (PHQ-9), and Perceived Stress Scale (PSS) for determining the severity of antenatal depression and suicide risk. Methods Extracted from a multi-site birth cohort study in eight countries, we test the reliability and validity of tri-scales among 148 women in the third trimester and 3-months after childbirth in Vietnam. Results Reliability testing achieved good internal consistency for the set of scales (Alpha = 0.75–0.81). The multitrait-multimethods matrix and SEM model indicated a good fit [Chi-square (230) = 337.5, p < 0.001; Root Mean Square Error of approximation= 0.56, Comparative Fit Index= 0.91] and good discriminant validity of WHO-5 lower discriminant validity of PSS and PHQ-9. The proportion of correctly classified cases and optimum balanced indicators of sensitivity and specificity suggested the cut-off scores of ≥ 6 for PHQ-9 and ≥ 25 for PSS for suicide risk screening. Regarding to predictive validity for postpartum depression of PHQ-9, we found that the cut-off scores of ≥ 6 for prenatal PHQ-9 screening can predict approx.70% of mild postpartum depression cases after 3-month childbirth. Conclusions This present study suggested adequate validity and reliability of the WHO-5, PHQ9 and PSS to measure antenatal depression and suicide risk in Vietnam. Key messages Further studies might consider to use one or a set of scales to understand multiple domains of mental disorder as it is simple to administer and acceptable duration for completion in the community.

No abstract

Background This study examined the intergenerational effects of being exposed to childhood maltreatment (CM) and prenatal intimate partner violence (p-IPV) on perinatal mental distress and birth outcomes in central Vietnam. Methods A birth cohort study in Hue City, Vietnam was conducted with 150 women in the third trimester of pregnancy (Wave 1) and three months after childbirth (Wave 2). Using multivariable logistic regression models, augmented inverse-probability-weighted estimators and structural equation modelling (SEM), we analyzed a theoretical model by evaluating adjusted risk differences and pathways between CM, p-IPV and subsequent perinatal adversity and indicators of infant health problems. Results One in two pregnant women experienced at least one form of CM (55.03%) and one in ten pregnant women experienced both CM and p-IPV (10.67%). Mothers who experienced p-IPV or witnessed IPV as a child were approximately twice as likely to experience poor mental health during pregnancy [ARR 1.94, 95% CI (1.20-3.15)]. Infants had a two-fold higher risk of adverse birth outcomes (low birth weight, preterm birth, admission to neonatal intensive care) [ARR 2.45 95% CI (1.42, 4.25)] if their mothers experienced any form of p-IPV, with greater risk if their mothers were exposed to both CM and p-IPV [ARR 3.45 95% CI (1.40, 8.53)]. Notably, significant pathways to p-IPV were found via adverse childhood experience (ACE) events (β = 0.13), neighborhood disorder (β = 0.14) and partner support (β = -1.3). Conclusions These results emphasize the detrimental and prolonged nature of the effect of violence during childhood and pregnancy. Exposure to childhood maltreatment and violence during pregnancy increases the risk of maternal mental health difficulties and adverse birth outcomes. Antenatal care systems need to be responsive to women’s previous experiences of violence and maternal mental health. The significant protective role of partner support and social support should also be considered when designing tailored interventions to address violence during pregnancy. Key messages Mothers with violent and adverse family backgrounds have twice the risk of poor mental health during pregnancy, and their infants have twice the risk of adverse birth outcomes. Social support during pregnancy may have a buffering effect by reducing the long-term impact of childhood traumatic events.