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Improving the biological nitrogen fixation of rhizosphere bacteria in rice is expected to improve plant growth and productivity. Most studies have focused on the application of a single N2-fixing bacterium on rice plants. Little is known about the beneficial impacts of a bacterial consortium, which is known as the microbial synthetic community (SynCom) on rice growth, and the extent of the interaction with the microbial community. The study investigated the effect of a SynCom on rice growth and productivity. A SynCom consisting of three bacteria Azosprillium sp. NL1, Bradyrhizobium sp. NL2, and Azotobacter sp. NL3 was designed to increase the survival and density of root microorganisms. The microbial culture collections used for the reconstitution experiment were established using bacterium-free soil. A profound increase in bacterial root microbiota survival and density was observed in plants inoculated with either mono- or multi-synthetic microbial consortia. SynCom is essential for rice plant growth by improving shoot ramification and root development. The results showed that SynCom could increase the total root nitrogen-fixing (%Ndfa) value by 51.6%, with Azotobacter sp. NL3 being the most dominant. High levels of indole acetic acid production in the range of 0.65–0.8 ng per g root were observed in Azosprillium sp. NL1 and Azotobacter sp. NL3. This indicates Azotobacter sp. NL3 is a nitrogen-fixing rhizosphere bacterium that is dominant in rice-amended soils. These results support the early application of the designed SynCom as a feasible strategy for the induction of nitrogen fixation, suggesting a role for earlier effects on rhizosphere colonization and tillering of plants.

Objective This study aims to explore the associated impairments of cerebral palsy (CP) and their correlates among children with CP in Vietnam.Design Descriptive cross-sectional study using hospital-based surveillance.Setting National Children’s Hospital, Hanoi, Vietnam between June and November 2017.Participants 765 children with CP were recruited.Outcome measures We assessed clinical characteristics of CP, associated impairments (epilepsy, intellectual, visual, hearing, speech impairments) and their correlates. We performed descriptive analyses (median, IQR and proportion). χ2 test and Fisher’s exact test were used for categorical variables. Univariate logistic regression and multivariate logistic regression models were established and associated impairments were included as independent variables.Results The median age of children was 1.7 years (IQR=2.7). Quadriplegia was the predominant subtype (69.5%) and 46.5% were at Gross Motor Function Classification System level IV–V. Of children, 76.3% had ≥one associated impairment, most commonly speech or intellectual impairments (59.1% and 57.8%, respectively). Severity of motor impairment, type of CP, maternal and perinatal factors (eg, gestational age, perinatal asphyxia, timing of injury causing CP) were associated with greater risk of associated impairments.Conclusion Children with CP have a high burden of associated impairments. Findings from our study will inform the development and implementation of appropriate screening and interventions and reduce the long-term adverse effects of these impairments on individuals with CP and their socioeconomic impact.

The efficacy of potable water and antimicrobial agents, including turmeric extract, black pepper extract, sodium chloride and sodium bicarbonate, in reducing Listeria monocytogenes on the leaf mustard (Brassica integrifolia) and iceberg lettuce (Lactuca sativa L.) was compared. The uncontaminated samples of two raw leafy vegetables were inoculated with L. monocytogenes at a concentration of 5 log and 7 log colony-forming units (CFU) g-1 for 1 h. At the high L. monocytogenes contamination level, the treatment with black pepper extract 0.6 mg mL-1 for 5 min was found to produce the most considerable decrease in L. monocytogenes counts, resulting in 1.44 log and 1.68 log reduction on leaf mustard and iceberg lettuce, respectively. Similarly, the black pepper extract also showed the highest L. monocytogenes reduction, approximately 0.79 log CFU g-1 on two leafy vegetables at the low contamination level. However, the odour of black pepper extract was left on the vegetables after being washed.

SiO2@Ag nanocomposite (NC) has been synthesized by the chemical reduction and Stӧber method for Metal-enhanced fluorescence (MEF) of Rhodmine 6G (R6G) and Surface-enhanced Raman spectroscopy (SERS) of Malachite green (MG). As-synthesized SiO2@Ag NC indicated SiO2 nanosphere (NS) and Ag nanoparticle (NP) morphologies. The SiO2@Ag NC was high quality with a well-defined crystallite phase with average sizes of 24 nm and 132 nm for Ag NP and SiO2 NC, respectively. By using SiO2@Ag NC, the photoluminescence (PL) intensity of the R6G (at 59.17 ppm) was increased approximately 133 times. The SERS of the MG (at 1.0 ppm) with SiO2@Ag NC as substrate clearly observed vibrational modes in MG dye at 798, 916, 1172, 1394, and 1616 cm−1. As a result, the SERS enhancement factor (EFSERS) at 1172 cm−1 obtained 6.3 × 106. This initial study points to the potential of SiO2@Ag NC as a promising material for MEF and SERS substrates to detect dyes at low concentrations. [ABSTRACT FROM AUTHOR]

This study investigates the climate resilience of coastal communities in Vietnam’s Nghe An province, a region highly exposed due to its extensive coastline and dense population. Employing the Climate Disaster Resilience Index (CDRI), the research assesses the resilience of three districts — Quynh Luu, Dien Chau, and Nghi Loc — to climate-induced disasters. The analysis reveals good to high overall resilience across five dimensions (physical, social, economic, institutional, and natural). Dien Chau boasts the highest score (4.06), followed by Quynh Luu (4.04), and Nghi Loc (4.01). While strong infrastructure and essential services contribute to high physical resilience, social capital development requires further attention. Economic resilience is bolstered by employment rates, but income and asset accumulation need improvement. Effective policies and disaster risk management strategies highlight strong institutional resilience. Natural resource management demonstrates adaptability, but land-use planning warrants enhancement. This study underscores the districts’ good preparedness for climate challenges while pinpointing areas for improvement across all CDRI dimensions. By addressing these vulnerabilities, Nghe An’s coastal communities can further strengthen their resilience.

Evaluation of E-Learning resources plays a significant role in the context of pedagogic systems. Resource evaluation is important in both conventional ‘talk-and-chalk’ teaching and in blended learning. In on-line (e-learning) teaching [an enforced feature of pedagogic systems in tertiary education during the Covid-19 pandemic] the effective evaluation of teaching resources has obtained importance given the lack of ‘face-to-face’ student-teached interaction. Moreover, the enforced use of e-learning has demonstrated the effectiveness of on-line pedagogic systems, which has been argued in blended learning pedagogic systems. Additionally, in e-learning, the lack of ‘face-to-face’ meetings [between teaching staff and students and in staff meetings] makes feedback (positive and negative) important for all actors in the pedagogic system. In this paper we present a novel approach to enable effective evaluation of teaching resources, which provides effective group decision-support designed to evaluate e-learning resources, enhancing students’ satisfaction. The proposed approach employs Picture Fuzzy Sets to quantify survey responses from actors, including: agree, disagree, neutral, and refuse to answer. In our approach, the system can manage the evaluation of e-learning resources based on both explicit and tacit knowledge using a picture fuzzy rule-based approach in which linguistic semantic terms are used to express rules and preferences. The proposed system has been tested using e-learning case studies with the goal of enhancing the learning experience and increasing students' satisfaction. Experimental results demonstrate that our proposed approach achieves a significant improvement in performance in the evaluation of e-learning resources.

Titanium dioxide/graphene aerogel (TiO2/GA) was synthesized via a one-pot hydrothermal method and characterized by various spectroscopic techniques, including X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscope, transmission electron microscopy, Raman spectroscopy, and UV-Vis spectroscopy. The influences of pH and TiO2/GA dose on the photocatalytic performance were investigated against positive dye methylene blue (MB) under UV light control. The characterization of TiO2/GA revealed that the synthesized TiO2 nanosize of 12–22.5 nm was uniformly distributed onto the graphene layers. The bandgap of the as-prepared nanocomposite was 2.63 eV, lower than that of pure TiO2 (3.2 eV). The kinetic studies exhibited that the adsorption–desorption equilibrium was achieved after 60 min following the pseudo-second-order. Meanwhile, 99.9% of MB was eliminated after 120 min at pH 9 with a 20 mg catalyst. The degradation data were well fitted to the pseudo-first-order kinetic model. Accordingly, applying TiO2/GA as an efficient photocatalyst indicates a potential pathway for the degradation of organic contaminants in wastewater treatment.

There is a pressing need to establish surveillance systems for antimicrobial use (AMU) intended for animal production particularly in many low- and middle-income countries. This is an extremely challenging task, notably due to the wide range of animal species, production types and antimicrobials available in the market. In Vietnam, farmers commonly buy antimicrobials from veterinary drug shops. Therefore, veterinary drug shops are a potential target for data collection on AMU. We collected antimicrobial sales data at veterinary drug shops and estimated the amount of AMU in different animal species by antimicrobial active ingredient (AAI) class using different measurement metrics. We compiled information on all antimicrobials licensed in Vietnam and used this information to develop a mobile application to capture sales of antimicrobials intended for use in poultry, pig, and ruminant. We provided tablets with this application to 60 veterinary drug shops in two provinces of the country (Bac Giang in the north, Dong Thap in the south; three districts and 30 shops per province) for data collection over 3 weeks. Total sales of antimicrobials were extrapolated to 1 year, and these amounts were related to three different denominator estimates in each province including standing animal body weight, animal biomass, and Population Correction Unit (PCU). A total of 3,960 transactions [2,577 (median 75.5 per shop) in Bac Giang; 1,383 (median 28.5 per shop) in Dong Thap] of 831 different antimicrobial-containing products were recorded in the 3-week period. Sales of 57 AAIs belonging to 17 classes were recorded. In the three Bac Giang districts, we estimated that 242.0 kg of AAI were hypothetically sold over 1 year. Of those, 202.2 kg (83.6%) were intended for poultry, 19.8 kg (8.1%) for pigs, and 20.0 kg (8.3%) for ruminants. In Dong Thap, an estimated 48.4 kg of antimicrobials were sold, including 28.9 kg (59.7%) for poultry, 16.0 kg (33.1%) for pigs, and 3.5 kg (7.2%) for ruminants. After standardized by different animal population denominators, AMU in Bac Giang amounted to 1129.2 mg/kg standing animal body weight, 480.2 mg/kg biomass, and 636.1 mg/kg PCU. In Dong Thap, AMU figures were 1211.0 mg/kg standing animal body weight, 595.8 mg/kg biomass and 818.5 mg/kg PCU. We discuss the observed differences between species, location and metrics, as well as the potential advantages and limitations (including potential sources of bias) of this methodology and its applicability at country level. Retail level data collection can effectively be integrated into AMU surveillance systems that help identify priority AMU management areas (species, regions, and antimicrobial classes), establish national benchmarks and reduction targets.

Background: Early detection of autism spectrum disorders (ASDs) is essential given the under-reported cases in low- and middle-income countries. This first national representative survey was conducted to explore the prevalence of ASDs amongst 18 and 30 months in seven provinces in Vietnam. Design and Method: During 2017- 2018, a national cross-sectional and population-based survey for autism spectrum disorder (ASD) amongst 40,243 children aged 18 to 30 months was conducted in 7 provinces representing the socio-economic regions of Vietnam. M-CHAT was used to screen children and then confirmed by diagnostic assessment using DSM-IV criteria. Results: The prevalence of ASDs amongst children aged 18 and 30 months in Vietnam was high (0.758% or 1 in 132 children). Urban setting, male gender, and hereditable genes were associated with ASD prevalence. Conclusion: ASDs amongst children aged 18 and 30 months in Vietnam tend to be increasing and are similar to this rate in other middle-income countries but lower than that in Western countries. This under-recognized public health problem amongst children should be addressed by early detection and intervention for families with affected children.

Effective medium approximations are constructed in this paper to estimate the macroscopic conductivity of coated-inclusion composites with thin anisotropic coating. The two-phase coated-inclusion are substituted by equivalent one-phase inclusion, using the multi-coated spheres assemblage and the differential substitution approaches. Then, the usual effective medium approximation schemes are applied to the equivalent medium to estimate the conductivity of original three-phase composites. The results obtained were compared with the numerical simulation by finite element method in 2D show the effectiveness of the methods.

The study aims to evaluate the infection prevalence, virulence gene distribution and antimicrobial resistance of Aeromonas hydrophila associated in diseased outbreaks of cultured freshwater fish in Northern Vietnam. The confirmed A. hydrophila were screened for the presence of the five pitutative-virulence genes including aerolysin (aerA), hemolysin (hlyA), cytotonic enterotoxin (act), heat-labile cytotonic enterotoxin (alt), and heat-stable enterotoxin (ast), and examined the susceptibility to 16 antibiotics. A total of 236 A. hydrophila isolates were recovered and confirmed from 506 diseased fish by phenotypic tests, PCR assays, and gyrB, rpoB sequenced analyses, corresponding to the infection prevalence at 46.4%. A total of 88.9% of A. hydrophila isolates harbored at least one of the tested virulence genes. The genes aerA and act were most frequently found (80.5% and 80.1%, respectively) while the ast gene was absent in all isolates. The resistance to oxacillin, amoxicillin and vancomycin exhibited the highest frequencies (>70%), followed by erythromycin, oxytetracycline, florfenicol, and sulfamethoxazole/trimethoprim (9.3–47.2%). The multiple antibiotic resistance (MAR) index ranged between 0.13–0.88 with 74.7% of the isolates having MAR values higher than 0.2. The results present a warning for aquaculture farmers and managers in preventing the spread of A. hydrophila and minimizing antibiotic resistance of this pathogen in fish farming systems.

Resistance to artemisinin derivatives, the most potent antimalarial drugs currently used, has emerged in Southeast Asia and threatens to spread to Africa. We report a case of malaria in a man who returned to Vietnam after 3 years in Angola that did not respond to intravenous artesunate and clindamycin or an oral artemisinin-based combination.

Crosstalk between hormones and secondary metabolites regulates the interactions between plants and stress. However, little is known about the effects of hormone crosstalk on the concentration of flavonoids in seeds. In this study, we identified abscisic acid (ABA) as a negative regulator of flavonoid accumulation in soybean seeds under drought‐stress conditions. Alterations in flavonoid accumulation at several intensities of water stress, followed by a recovery period, were measured during the soybean seed‐filling stage. Low soil moisture (SM 10%) significantly decreased the total flavonoid content in seeds. The decline in flavonoid content was proportional to the severity of drought stress and was dependent on the activities of phenylalanine ammonia‐lyase (PAL) and chalcone synthase (CHS), two key phenylpropanoid pathway enzymes. The expression of phenylalanine ammonia‐lyase 1 (GmPAL1), chalcone isomerase 1A (GmCHI1A), and chalcone synthase 8 (GmCHS8) was associated with phenolic and flavonoid accumulation in soybean seeds of plants subjected to drought stress. Interestingly, the expression levels of GmCHS8 were highly correlated with flavonoid levels under drought stress and water recovery conditions. Cinnamic acid, which is a biosynthesis precursor shared by both phenylpropanoid metabolism and salicylic acid (SA) biosynthesis, decreased under drought stress conditions. Notably, exogenous ABA suppressed the expression of GmPAL1, which encodes the first rate‐limiting enzyme in the phenylpropanoid biosynthesis pathway and affects downstream products such as SA and flavonoids. In conclusion, drought stress altered the phenylpropanoid‐derived compounds, at least with regard to flavonoid and SA accumulation in seeds, which was regulated by antagonistic interactions with ABA. [ABSTRACT FROM AUTHOR]

Background: Peanut (Arachis hypogaea L.) is one of the oil and cash crops in Vietnam. However, owing to the lack of appropriate management practices, the production and the area under cultivation of peanut have remained low. Mulches are the key factors contributing to promoting crop development and early harvest and increasing yields. Methods: The experiment consisted of three mulch treatments, viz., plastic mulch, straw mulch and no-mulch control. All the treatments were replicated thrice in a complete randomized block design. Result: In the conditions of mulch, the plant growth parameters (germination rate, growing time, plant height, number of branches per plant), leaf area index, the number of nodules per plant, dry matter accumulation, yield components and yield of peanut was much higher than that of no-mulch control. Among the mulches, plastic mulch was found superior to straw mulch in the pod yields and wateruse efficiency and moisture conservation, thereby can be considered as a reliable practice for increasing the productivity of peanut on the coastal sandy land in Nghe An province, Vietnam. [ABSTRACT FROM AUTHOR]