Spatial and temporal evolution of groundwater arsenic contamination in the Red River delta, Vietnam: Interplay of mobilisation and retardation processes.

Geogenic arsenic (As) contamination of groundwater poses a major threat to global health, particularly in Asia. To mitigate this exposure, groundwater is increasingly extracted from low-As Pleistocene aquifers. This, however, disturbs groundwater flow and potentially draws high-As groundwater into low-As aquifers. Here we report a detailed characterisation of the Van Phuc aquifer in the Red River Delta region, Vietnam, where high-As groundwater from a Holocene aquifer is being drawn into a low-As Pleistocene aquifer. This study includes data from eight years (2010-2017) of groundwater observations to develop an understanding of the spatial and temporal evolution of the redox status and groundwater hydrochemistry. Arsenic concentrations were highly variable (0.5-510 µg/L) over spatial scales of <200 m. Five hydro(geo)chemical zones (indicated as A to E) were identified in the aquifer, each associated with specific As mobilisation and retardation processes. At the riverbank (zone A), As is mobilised from freshly deposited sediments where Fe(III)-reducing conditions occur. Arsenic is then transported across the Holocene aquifer (zone B), where the vertical intrusion of evaporative water, likely enriched in dissolved organic matter, promotes methanogenic conditions and further release of As (zone C). In the redox transition zone at the boundary of the two aquifers (zone D), groundwater arsenic concentrations decrease by sorption and incorporations onto Fe(II) carbonates and Fe(II)/Fe(III) (oxyhydr)oxides under reducing conditions. The sorption/incorporation of As onto Fe(III) minerals at the redox transition and in the Mn(IV)-reducing Pleistocene aquifer (zone E) has consistently kept As concentrations below 10 µg/L for the studied period of 2010-2017, and the location of the redox transition zone does not appear to have propagated significantly. Yet, the largest temporal hydrochemical changes were found in the Pleistocene aquifer caused by groundwater advection from the Holocene aquifer. This is critical and calls for detailed investigations.

Facile and Green Reduction of Graphene Oxide by a Reduced Polyoxometalate and Formation of a Nanohybrid.

An ecofriendly chemical reduction of graphene oxide (GO) in water is reported. The reducing agent is an electrochemically reduced Keggin-type polyoxometalate (SiW12 O40 5- ). Moreover, this process leads to the fabrication of SiW12 @rGO nanocomposite. This nanohybrid exhibits an electrochemical response which combines high faradic and capacitive currents due to high coverage of polyoxometalates on the rGO sheets. Therefore this material has strong potentiality for energy storage.

Does a novel prefilled injection device make postpartum oxytocin easier to administer? Results from midwives in Vietnam.

OBJECTIVE: to assess the acceptability of the Uniject prefilled injection device for delivery of oxytocin in the third stage of labour, and the effect of the device on overall willingness to perform active management of the third stage of labour (AMTSL). DESIGN: descriptive study that used baseline and post-intervention questionnaires. SETTING: three districts in northern Vietnam. The study population consisted of 52 midwives from two districts where AMTSL was already practiced, and 35 midwives from a district where AMTSL was introduced as part of the study. MEASUREMENTS AND FINDINGS: the majority of midwives reported that the Uniject device was easier to use and preferable compared with ampoules and standard syringes. They found the training materials easy to understand. KEY CONCLUSIONS: the use of a prefilled injection device overcame many of the barriers cited by midwives with regard to the use of oxytocin in ampoules, such as trying to break ampoules and fill syringes in a hurry. This device enabled midwives to deliver the correct dose of oxytocin in the third stage of labour in a safe and timely way, while attending to the other needs of the mother and her newborn baby. IMPLICATIONS FOR PRACTICE: use of a prefilled injection device for oxytocin may increase the acceptability and practice of AMTSL in primary level facilities, thus reducing maternal mortality due to postpartum haemorrhage.

The International Network on Public Health and Aging (INOPA): introducing a life course perspective to the public health agenda.

In this paper, we present an international network of researchers from projects examining the human aging process and its consequences. It is both vital and urgent to include aging and a life course perspective on the public health agenda, particularly in low-income countries. By announcing the network in a publication, we wish not just to position the network but, more importantly, to attract the attention of other potential collaborators either at the project, institutional, decision making, or applied level.

Reducing postpartum hemorrhage in Vietnam: assessing the effectiveness of active management of third-stage labor.

AIM: The study was undertaken to meet the need of the Ministry of Health to have local evidence on the effectiveness of active management of third-stage labor (AMTSL) in reducing the incidence of postpartum hemorrhage (PPH) > or = 500 mL and the need for PPH treatment. METHODS: Using a quasi-experimental design, AMTSL was introduced for all births attended by government midwives (at home, community, and district levels) in one district while standard practice without AMTSL was continued in three neighboring districts (with a 1:2 ratio of participants). Oxytocin (10 IU) was administered either by standard disposable syringe and needle or by a prefilled, single-use injection device. Postpartum blood loss was estimated using standard containers; other outcome measures included the duration of third stage, the need for additional treatments, and final maternal condition. A total of 3607 women participated (1236 in the intervention district and 2371 in the comparison districts). Multivariate logistic regression was used to control for age, parity, place of delivery, and first-stage oxytocin augmentation. RESULTS: AMTSL was associated with reduced risks for prolonged third stage beyond 30 min (odds ratio [OR] = 0.20, 95%; confidence interval [CI]: 0.11, 0.35), supplemental oxytocin (OR = 0.68, 95% CI: 0.49, 0.94), and bimanual compression (OR = 0.63, 95%; CI: 0.41, 0.98). When cases with first-stage oxytocin augmentation were excluded, AMTSL was associated with a 34% reduction in PPH incidence (OR = 0.66, 95%; CI: 0.45, 0.98). CONCLUSION: This study supports the value of AMTSL in reducing the incidence of PPH, shortening the third stage of labor, and reducing the need for additional treatments.