Background: Health literacy (HL) is an important factor in improving health inequalities in poor and marginalized groups. Assessing comprehensive HL is critical. In this study, we validated the use of a comprehensive short-form HL survey tool (HLS-SF12) and examined the determinants of HL among people in rural areas. Methods: A cross-sectional study was conducted in July 2019 on 440 people residing in mountainous areas in Vietnam. Health literacy was measured using the HLS-SF12. Personal characteristics were also collected. We analyzed data using confirmatory factor analysis, internal consistency analysis, and regression analysis. Results: The questionnaire demonstrated a good construct validity with satisfactory goodness-of-fit indices and item-scale convergent validity. The tool was reliable and homogeneous with Cronbach’s alpha = 0.79, with no floor/ceiling effects. People who were married had lower HL (regression coefficient B = −3.12; 95% confidence interval (CI) = −5.69, −0.56; p = 0.017) compared with those who never married. Higher education attainment (B = 3.41 to 10.44; p < 0.001), a better ability to pay for medication (B = 4.17 to 9.89; p < 0.001), and a tendency to view health-related TV/radio more often (B = 5.23 to 6.15; p < 0.001) were associated with higher HL. Conclusions: The HLS-SF12 is a valid survey tool for the evaluation of HL in rural populations. A number of personal characteristics were strongly associated with HL.

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Saltwater intrusion, a consequence of climate change and decreased water levels, has been increasingly severe in the Mekong Delta region. Thanh Phu District, Ben Tre Province, Vietnam, is a coastal region where agricultural production and local livelihood have been impaired by saltwater intrusion, resulting in the adoption of multiple coping strategies, including rotations and intercropping. This study aims to measure and evaluate soil and water quality indicators of multiple farming systems in Thanh Phu district and contributes to developing suitable cropping patterns. Soil indicators were pH, electrical conductivity, and exchangeable Na+. Water quality characteristics include pH, salinity, dissolved N and P, alkalinity, H2S, and chemical oxygen demand (COD). The results indicated that water pH and salinity were at suitable levels to support the growth of prawn but were below the critical level required to grow black tiger shrimp and white-legged shrimp. Water alkalinity, dissolved N, P, and COD were not constraining for the growth of shrimps. However, a significant concentration of H2S may cause disadvantages for shrimp growth.

Hospital wastewater contains pharmaceutical residues, chemicals, and pathogens that cause coloration and nourish pathogenic microorganisms. The objective of the study was to evaluate the effectiveness of a medical wastewater treatment system at Military Hospital 175 (Ho Chi Minh City, Vietnam) that combined a membrane bioreactor (MBR) system with nanofiltration (NF). The influent of the system was the wastewater discharged from the operating rooms of the hospital. The system has a capacity of 50 L/day and operates at three organic load rates (OLR) of 0.5, 1.5 and 2.5 kgCOD/m3day (COD: Chemical oxygen demand), in which each load rate operates for 40 days. The results showed that most nutritional criteria generally achieved positive results. Specifically, the average COD removal was shown to be consistently high throughout the three phases at 94%, 93.3%, and 92.7%, respectively. For removal of nitrogen, the system demonstrated efficiencies of 75%, 79%, and 83%, respectively, to three phases. The log removal value (LRV) for Escherichia coli and coliform bacteria were higher than four throughout the study period. The average removal efficiency for color and total iron was approximately 98% and 99%, respectively. The water quality after treatment, especially after NF, meets the Vietnamese standard of grade A. The arrangement in which the MBR preceded NF was also found to limit the amount of soil and solids entering subsequent treatment, which therefore improved the efficiency of NF, as demonstrated by the stability of post-NF transmembrane pressures throughout three cycles renewed by two backwashes.

The effects of ultrasonic and ozonation pretreatments on organic solubilization, anaerobic biodegradability, and biogas production were elucidated in this study. Two pretreatment methods for batch anaerobic digestion for biogas recovery with the same material and experimental conditions were the focus for comparison. Anaerobic digestion experiments were conducted at ambient temperature with the solid retention time set to 25 days. The obtained results indicated that the soluble chemical oxygen demand increased from 0.344 without pretreatment to 1.023 and 1.228 g/L with ultrasound and ozone pretreatments, respectively, whereas the yields of biogas production in the 25 days increased by 32.3 and 52.9% via ultrasonic irradiation and ozonation relative to the control case, respectively. The biodegradability of the organic compounds of the samples for the cases of ultrasound, ozone pretreatments, and control achieved 55.9, 64.31, and 39.18%, respectively, in terms of chemical oxygen demand (COD) removal efficiencies. The physicochemical characteristics of sludge flocs were investigated via scanning with particle sizes, which were obviously affected by pretreatments of sonication and ozonation, resulting in finer particles than in the control case.

Malignant pleural mesothelioma (MPM) is associated with a history of heavy, long-term exposure to asbestos. However, MPM may also be associated with simian virus 40 (SV40), a polyomavirus. The association between SV40 and MPM remains unclear. The present study was conducted in order to investigate the proportion of SV40 presence in the histological specimens of Vietnamese patients with MPM. Histological specimens were obtained from 45 patients (19 men and 26 women) with MPM at the Pham Ngoc Thach Hospital in Ho Chi Minh City, Vietnam. The specimens were processed and examined in order to detect the presence of the SV40 large T antigen (SV40 Tag) expression using immunohistochemistry. Of the 45 patients, 23 (51%) were epithelioid, 7 (16%) were biphasic, 6 (13%) were sarcomatoid, 4 (9%) were desmoplastic, 4 (9%) were well-differentiated papillary and 1 (2%) was the anaplastic subtype. In total, 9/45 patients (20%) demonstrated SV40 Tag expression. The proportion of patients that demonstrated SV40 Tag expression was not significantly different between the epithelioid subtype and the other subtypes (22 vs. 18%; P=1.000) or between the patients with stage IV disease and other stages (20 vs. 20%; P=1.000). The median survival time was not significantly different between the patients with or without SV40 Tag expression (196 vs. 236 days, P=0.8949). In summary, a 5th of the Vietnamese patients with MPM were associated with infection with SV40. SV40 may be a potential cause of MPM in Vietnam and this potential association requires additional studies.

Due to the impacts of climate change and the reduction in the flow of the Mekong River, saline intrusion into the inland has been an emergent and pressing issue. The purpose of this study is to analyze the effects of various saline conditions (0–25‰) on changes in some soil properties under laboratory conditions. Ten topsoil samples were collected from a depth of 0–20 cm in the dry seasons in the rice–corn rotation fields with low salinity, in Thanh Phu district, Ben Tre province, Vietnam. The examined criteria consisted of soil pH, soil electrical conductivity of the saturated paste extract (ECe), exchangeable Na, percentage of exchangeable Na, and content (%) of nitrogen and phosphorus. The results revealed that the pH range of soil decreased from 5.14–5.72 to 4.08–5.14 when the soil salinity increased from 0 to 25‰. At the salinity of 10‰ and higher, the available nitrogen began to decline. Meanwhile, the available phosphorus tended to decrease as the salinity increased past 12‰. Some measures are also discussed, with the aim of ensuring sustainable rice farming in the circumstances of increased salinity.

Silver nanoparticles (AgNPs) find a wide range of use in many fields, and the biosynthesis of AgNPs via biological routines has recently gained currency. In this study, Bacillus licheniformis TT01 strain was isolated from quail feces collected in Vietnam and evaluated for its ability to synthesize AgNPs. Through visual confirmation and ultraviolet and visible (UV–Vis) spectrum analysis, we found that the biosynthesis of AgNPs was realized in the process in which biomass of B. licheniformis TT01 was incubated with AgNO3 solution. Obtained AgNPs were then assayed for antibacterial activity against three species of bacteria, namely Escherichia coli, Bacillus cereus and Ralstoniasolanacearum, showing better inhibitory action than the AgNO3 solution and the bacterial extracellular fluid. The minimum inhibitory concentration (MIC) of AgNP solution was 206 ppm against E. coli and R. solanacearum and 343.3 against B. cereus. X-ray diffraction (XRD) and transmission electron microscopy (TEM) revealed that the obtained AgNPs had a spherical shape and sizes ranging from 2 to 22 nm, in which particles from 2 to 10 nm appeared with the highest frequency.