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In this work, the effect of gel polymer electrolytes (GPE) containing polyvinyl alcohol/polyethylene oxide (90/10, wt%) blend and different contents of sodium salt mixture (sodium acetate ( CH 3 COONa ) /sodium sulphate (Na 2 SO 4 ) = 50 / 50 wt % ) on the performance of solid-state supercapacitor was investigated. The active electrode of the solid-state supercapacitor was made from graphene nanoplatelets and carbon black. The results indicate that the sodium salt mixtures were easily mixed in polymer blend gel to make excellent GPE with large concentration of ionic liquid. At the sodium salt mixture content of 30%, the solid-state supercapacitor showed the best performance of electrode-specific capacitance of 93.768 F g - 1 at current density of 1 A g - 1 , energy density of 3.25 Wh kg - 1 and power density of 586.166 W kg - 1 . These results highly recommend the good potential of GPE for developing solid-state supercapacitor in the future.

The construction industry is a complex environment where high accident rates make significant contributions to cost overruns and time delays. Safety education is important in promoting a safe and healthful working environment in construction; however current pedagogical methods and tools at the tertiary level are unable to provide students with real practical and safety experiences. This study proposes an online social virtual reality (VR) system framework which allows students to perform role-playing, dialogic learning, and social interaction for construction safety and health education. The framework includes the following three modules: 1) Cooperative Distributed Safety Learning (CDSL) to understand root causes of accidents in construction site; 2) Hazard Inspection and Safety Cognition (HISC) to reflect on safety theories through hazard inspection within a social VR environment; 3) Active Safety Game-based Learning (ASGL) to enhance practical capacities by playing the safety training game in a 3D virtual environment. The system prototype is developed and evaluated with virtual scenarios derived from real safety cases to identify the system’s benefits and limitations. The results concluded that the social/collaborative virtual reality platform would improve construction safety & health education effectively.

Bats play a vital role in ecosystems through providing essential functions and services, such as pollination and pest control, but they face many threats from anthropogenic activities, climate change, and diseases. While establishing protected areas can be a conservation measure to mitigate bats’ population declines and habitats loss, the effectiveness of current protected areas in conserving bat species remains poorly understood. Using Vietnam as a case, this study aims to evaluate the representation of the existing protected area network for bats in terms of the proportion of their distribution ranges covered and the number of well-covered species. We also identified areas that would improve the representation using the spatial prioritization approach. Our results showed that while Vietnam’s protected area network provides better representation than random allocation, it currently only covers 6.12% of bat distribution ranges on average, leaving the distribution areas of more than 78 (96%) of the 81 species examined in this study insufficiently represented. Through the spatial prioritization, the forests in Central Highlands, western Central Coast, and Northwest were identified as the key regions for bats. Expanding the current network to cover 9% and 30% of the land under the national and global targets could improve the range coverage to 11.89% and 41.99%, respectively, reducing the number of poorly represented bats to 10–23 (12.3–28.4%) species. These findings offer critical insights for conservation practitioners and policymakers into prioritizing resources and efforts for improving conservation of not only bats in Vietnam but also biodiversity in general in other places.

Climate and land-cover changes are among major threats to biodiversity. However, the interactive effects of the two threats are often overlooked in conservation planning. Using 81 bat species occurring in Vietnam as a case, we investigated the individual and interactive effects of climate and land-cover changes, highlighting the importance of this information for conservation efforts. By using species distribution models, we predicted the potential changes in range size among species and in species richness across Vietnam by the 2050s, considering projected climate and land-cover changes under two emission scenarios. Our results revealed that both threats individually would have predominantly negative effects on bats in Vietnam. Moreover, when these threats occur simultaneously, their interactions would generally intensify the impacts by mitigating individual positive effects and/or enhancing negative effects. However, we also found large interspecific and geographic variations in the direction and magnitude of these effects. Forest specialists, insectivores and cave-roosting species were predicted to be particularly vulnerable to the negative effects, with northern and southern Vietnam being more affected. These results underscore the urgent need to incorporate both climate and land-cover changes, as well as their interactions, into conservation planning for bats in Vietnam and biodiversity in general. The species-specific and spatially-explicit information regarding the impacts of the two threats can guide conservation actions, allowing us to target more manageable and less uncertain threats, as well as prioritize the protection of more vulnerable species.

Background Early essential newborn care has been implemented in countries regardless high or low neonatal mortality. This study aims to investigate the current practice of skin-to-skin contact (SSC) and its effect on exclusive breastfeeding during the hospital stay. Methods This is a cross-sectional study of 1812 Vietnamese mothers in multicenter. A questionnaire answered by the mothers was used to assess the duration of both SSC and breastfeeding practices. Multivariable logistic regression was used to identify a dose–response relationship between early SSC and prevalence of exclusive breastfeeding in hospital. Results There were 88.7% of mothers experiencing SSC with their infants right after birth and the highest prevalence of SSC was found in district hospitals. Among those experiencing SSC, 18.8% of the infants received more than 90 min of SSC and completed the first breastfeeding during SSC time. Prevalence of exclusive breastfeeding during maternity hospital stay was 46.7%. We found a significant dose–response relation between the duration of SSC and exclusive breastfeeding in hospital. Compared with infants without SSC, the prevalence of exclusive breastfeeding was higher in infants who experienced SSC for 15–90 min (adjusted odds ratio [aOR], 95% confidence interval [95%-CI]: 2.62 [1.61–4.27]) and more than 90 min (aOR [95%-CI]: 5.98 [3.48–10.28]). Completed first breastfeeding during SSC time (aOR [95%-CI]: 4.24 [3.28–5.47]) and being born in district hospitals (aOR [95%-CI]: 2.35 [1.79–3.09]) were associated with increased prevalence of exclusive breastfeeding during hospital stay. On the other hand, mother education level as high school/intermediate (aOR [95%-CI]: 0.58 [0.42–0.82]) and place of residence classified as rural decreased odds of exclusive breastfeeding in hospital (aOR [95%-CI]: 0.78 [0.61–0.99]). Conclusion Our results demonstrate a strong dose–response relationship between duration of SSC and exclusive breastfeeding in hospital. Interventions that support exclusive breastfeeding during hospital stay, especially achieving prolonged uninterrupted SSC, could improve the duration of breastfeeding.

Carbon dioxide (CO2) is one of the major greenhouse gases that has been shown to cause global warming. Decreasing CO2 emissions plays an important role to minimize the impact of climate change. The utilization of CO2 gas as a cheap and sustainable source to produce higher value-added chemicals such as formic acid, methanol, methane, and acetic acid has been attracting much attention. The electrochemical reduction of CO2 catalyzed by whole-cell biocatalysts is a promising process for the production of value-added chemicals because it does not require costly enzyme purification steps and the supply of exogenous cofactors such as NADH. This study covered the recent applications of the diversity of microorganisms (pure cultures such as Shewanella oneidensis MR1, Sporomusa species, and Clostridium species and mixed cultures) as whole-cell biocatalysts to produce a wide range of value-added chemicals including methane, carboxylates (e.g., formate, acetate, butyrate, caproate), alcohols (e.g., ethanol, butanol), and bioplastics (e.g., Polyhydroxy butyrate). Remarkably, this study provided insights into the molecular levels of the proteins/enzymes (e.g., formate hydrogenases for CO2 reduction into formate and electron-transporting proteins such as c-type cytochromes) of microorganisms which are involved in the electrochemical reduction of CO2 into value-added chemicals for the suitable application of the microorganism in the chemical reduction of CO2 and enhancing the catalytic efficiency of the microorganisms toward the reaction. Moreover, this study provided some strategies to enhance the performance of the reduction of CO2 to produce value-added chemicals catalyzed by whole-cell biocatalysts.

Mangrove ecosystems play important ecological roles, including the mitigation of global climate change and biodiversity conservation. However, they have received little attention from scientists for the research and conservation of bats and general biodiversity. In Vietnam, bat species inhabiting mangroves have been relatively unstudied, while this ecosystem is located along the country’s coastal zones and has declined dramatically due to the development of agriculture, wind energy and other threats. To initially fill this gap, five bat surveys were conducted between September 2019 and November 2021 within Ha Long Bay and Ben Tre province, which contain representative mangrove areas of northern and southern regions of Vietnam, respectively. Bats were captured using mist nets, mobile nets and hand nets. Their echolocation calls were recorded and analyzed using the PCTape system and Selena software, respectively. Five species were captured and recorded: Cynopterus brachyotis, Macroglossus minimus, Myotis hasselti, Myotis pilosus and Taphozous melanopogon. They are all new to both Ha Long Bay and Ben Tre province. Four species (C. brachyotis, M. minimus, M. hasselti and M. pilosus) have been rarely documented from other ecosystems in Vietnam but have commonly been recorded and captured in mangrove areas. Of these species, M. pilosus is a globally “Vulnerable” species. While searching for prey, Myotis hasselti emitted high energy echolocation calls sweeping from about 96 to about 24 kHz with a signal duration of about 5 ms. This species sometimes uses social calls of a horseshoe-shaped structure, which last about 15 ms and are emitted about 26 ms in front of a search call. Results from our surveys indicated the importance and potential of mangroves for bat research and conservation.

In order to proactively prevent accidents and injuries in construction, tertiary safety education should equip students with adequate safety knowledge and skills. However, in most construction curricula, safety is considered a low priority, and safety education is delivered in isolation, without sufficient interaction and practical experience to improve safety learning. On the other hand, anatomical theory in medicine has been adopted by and proved advantageous to various scientific disciplines. With this regard, this study presents an interactive construction safety education system using building anatomy modelling (BAM) based on the integration of anatomical theory and state-of-the-art visualization technologies. The BAM system comprises two modules: (1) knowledge acquisition module, which delivers safety knowledge to students; and (2) practical experience module, which enables students to interact with BAM to improve their hazard identification and elimination skills. The building anatomy concept (BAC) and BAM prototype are evaluated through interactive system trials with educators and learners. Findings suggest the BAC has significant pedagogic potential, and the proposed system can effectively provide safety knowledge and interactively support the development of practical safety skills of learners.

Carbon dioxide (CO[sub.2]) is one of the major greenhouse gases that has been shown to cause global warming. Decreasing CO[sub.2] emissions plays an important role to minimize the impact of climate change. The utilization of CO[sub.2] gas as a cheap and sustainable source to produce higher value-added chemicals such as formic acid, methanol, methane, and acetic acid has been attracting much attention. The electrochemical reduction of CO[sub.2] catalyzed by whole-cell biocatalysts is a promising process for the production of value-added chemicals because it does not require costly enzyme purification steps and the supply of exogenous cofactors such as NADH. This study covered the recent applications of the diversity of microorganisms (pure cultures such as Shewanella oneidensis MR1, Sporomusa species, and Clostridium species and mixed cultures) as whole-cell biocatalysts to produce a wide range of value-added chemicals including methane, carboxylates (e.g., formate, acetate, butyrate, caproate), alcohols (e.g., ethanol, butanol), and bioplastics (e.g., Polyhydroxy butyrate). Remarkably, this study provided insights into the molecular levels of the proteins/enzymes (e.g., formate hydrogenases for CO[sub.2] reduction into formate and electron-transporting proteins such as c-type cytochromes) of microorganisms which are involved in the electrochemical reduction of CO[sub.2] into value-added chemicals for the suitable application of the microorganism in the chemical reduction of CO[sub.2] and enhancing the catalytic efficiency of the microorganisms toward the reaction. Moreover, this study provided some strategies to enhance the performance of the reduction of CO[sub.2] to produce value-added chemicals catalyzed by whole-cell biocatalysts.

Magnetic droplets are non-topological magnetodynamical solitons displaying a wide range of complex dynamic phenomena with potential for microwave signal generation. Bubbles, on the other hand, are internally static cylindrical magnetic domains, stabilized by external fields and magnetostatic interactions. In its original theory, the droplet was described as an imminently collapsing bubble stabilized by spin transfer torque and, in its zero-frequency limit, as equivalent to a bubble. Without nanoscale lateral confinement, pinning, or an external applied field, such a nanobubble is unstable, and should collapse. Here, we show that we can freeze dynamic droplets into static nanobubbles by decreasing the magnetic field. While the bubble has virtually the same resistance as the droplet, all signs of low-frequency microwave noise disappear. The transition is fully reversible and the bubble can be thawed back into a droplet if the magnetic field is increased under current. Whereas the droplet collapses without a sustaining current, the bubble is highly stable and remains intact for days without external drive. Electrical measurements are complemented by direct observation using scanning transmission x-ray microscopy, which corroborates the analysis and confirms that the bubble is stabilized by pinning. Magnetic droplets are a type of non-topological magnetic soliton, which are stabilised and sustained by spin-transfer torques for instance. Without this, they would collapse. Here Ahlberg et al show that by decreasing the applied magnetic field, droplets can be frozen, forming a static nanobubble