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Nguyen Le Trung,1,2 Pham Quoc Toan,1,3 Le Viet Thang,1,3 Nguyen Dinh Ngan,1,2 Nguyen Chien Thang,1,2 Nguyen Van Cuong,1,2 Nguyen Van Dam,1,2 Hoang Tuan Anh,1,2 Vo Thi Hang,1,2 Nguyen Kien Trung,4 Do Nhu Binh,1,5 Vu Anh Tuan6 1Vietnam Military Medical University, Hanoi, 12108, Vietnam; 2Vietnam Department of Opthalmology, Military Hospital 103, Hanoi, 12108, Vietnam; 3Vietnam Department of Nephrology, Military Hospital 103, Hanoi, 12108, Vietnam; 4Vietnam National Eye Hospital, Hanoi, 11613, Vietnam; 5Vietnam Department of Infectious Diseases, Military Hospital 103, Hanoi, 12108, Vietnam; 6Vietnam Hanoi Medical University, Hanoi, 11601, VietnamCorrespondence: Vu Anh Tuan Email vuanhtuan64@gmail.comPurpose: Patients with end-stage renal failure are susceptible to dry eye disease. This study explores the relationship between dry eye disease and influence factors.Patients and Methods: The control group consisted of 57 healthy subjects who were kidney donors. They were of the same age and sex as the kidney transplant recipients. The outcome variable was the dry eye condition of the participants. The Schirmer test confirmed dry eye disease, TBUT (breakup time test), and the Eye Surface Disease Index (OSDI) questionnaire, using linear regression to evaluate the association.Results: The total number of subjects was 146 (89 kidney recipients and 57 kidney donors). When univariate analysis found the level of visual acuity, the age group involved was statistically significant, while the other factors were not statistically significant. In multivariable logistic regression analysis, age (odds ratio: 2.8, p< 0.05), smoking history (odd ratio: 0.1, p< 0.05), corneal conjunctival calcification (odd ratio: 0.2, p< 0.05); central corneal thickness (odd ratio: 1.02, p< 0.05) is considered to be an influence factor for disease progression.Conclusion: Age group, smoking history, corneal central thickness, and conjunctival calcification are factors for dry eye disease in patients preparing to receive a kidney. These results reinforce the evidence for multifactorial dry eye disease in patients with renal impairment.Keywords: dry eye, renal failure, renal transplant, Hanoi Vietnam

Abstract Background The prevalence of functional disabilities, including difficulties in performing activities of daily living (ADLs) and instrumental activities of daily living (IADLs), increased significantly in recent years and burdened the healthcare system. Methods We analysed data from Korean Longitudinal Study of Aging (KLOSA) surveys, including participants aged 65 or older at baseline (2008), and participated in all 4-year follow-up periods in 2012, 2016, and 2020. A 4-year follow-up cohort study was applied to specify the change in functional disability and its trend over time among older adults. The generalized estimation equation (GEE) model was used to verify the uptrend of functional disability. Logistic regression analyses were applied to examine the influence of demographic and health parameters on the change in functional disability. Results The prevalence of ADL disability was 2.24% at baseline, increased to 3.10% after four years, 6.42% after eight years, and reached 11.12% after 12 years, five times higher than that at baseline. For IADL disability, they were 10.67%, 10.61%, 18.18%, and 25.57%, respectively. The uptrend of ADL disability in persons aged 65–74 (1.77% at baseline, increased to 7.65% in 2020, 12-year change of 5.88%) was slower than in those aged 75 or older (4.22% at baseline, increased to 25.90% in 2020, 12-year change of 21.68%). IADL disability were consistent with this. The high ADL/IADL disability rate was also present among persons with poor health status, physical inactivity, depression, dementia, and multiple chronic diseases. The relative risk of ADL/IADL disability in persons with a history of functional disability was significantly higher than in those without historical disabilities. Conclusion The study verified the change in functional disability and its upward trend over time by older adults’ demographic and health parameters. Functional disability was relatively flat tending to increase slowly during the early years but increased rapidly in the following years. Factors that strongly influenced the change in prevalence and the uptrend of functional disability were advanced age, living alone, being underweight or obese, poor health status, physical inactivity, depression, dementia, having multiple chronic diseases, and especially having a historical disability.

Bidens pilosa L., native to South America, is valued for its purposes as a food and medicine. The study aimed to examine phenolics, antioxidant activity and inhibitory effects of B. pilosa flower and leaf extracts on albumin denaturation, α-glucosidase, α-amylase, xanthine oxidase, and tyrosinase. The choice of extractants (water, methanol, acetone, and ethyl acetate) greatly influenced the phenolic content and bioactivities of the extracts. The results demonstrated the flower and leaf extracts differed significantly with respect to total phenolic content and abilities to inhibit albumin denaturation, α-amylase, and xanthine oxidase. The ethyl acetate extracts may show the strongest activity to scavenge DPPH radicals, to inhibit α-amylase and α-glucosidase, and to protect albumin against denaturation. The aqueous extract possessed the strongest capacity to inhibit xanthine oxidase while the acetonic extract was more effective in suppressing tyrosinase compared to the others.

Bài báo này trình bày cách tổng hợp vật liệu Fe3O4 cấu trúc xốp bằng phương pháp thuỷ nhiệt. Kết quả cho thấy vật liệu Fe3O4 hình thành từ các hạt nano sơ cấp dạng tấm, có cấu trúc xốp và diện tích bề mặt riêng lớn. Hơn nữa, bề mặt vật liệu Fe3O4 được pha tạp một cách đồng đều với các hạt nano Au với kích thước trung bình khoảng 10 nm, tạo thành vật liệu nanocomposite Fe3O4@Au cấu trúc xốp. Vật liệu Fe3O4@Au được sử dụng để phủ lên bề mặt điện cực than thuỷ tinh (Fe3O4@Au-GCE) để làm cảm biến điện hoá trong xác định chloramphenicol. Điện cực này có khả năng xác định chloramphenicol với khoảng tuyến tính 2–10 μM và giới hạn phát hiện 0,17 μM.

In this work, the bismuth-terephthalate frameworks (Bi-BDC) were prepared by a facile solvothermal approach. The prepared Bi-BDC MOFs were characterized by XRD, TGA, FT-IR, SEM, and UV-vis DRS analyses. The results indicated that the synthesis temperature affected the crystallinity and morphologies of the Bi-BDC frameworks. Notably, the produced Bi-BDC at low temperatures (80 and 100 oC) exhibited enhanced light absorption ability. The photodegradation experiment of rhodamine (RhB) showed that the prepared Bi-BDC-100 sample had the highest removal efficiency of ca. ∼ 98% after 270 min of visible LED light illumination. In addition, the HPLC-MS analysis revealed that RhB was photocatalytically degraded over the Bi-BDC via the carboxylation and dealkylation mechanism. Furthermore, the removal efficiency of the organic pollutant was optimized by monitoring the effects of catalyst dosage, dye concentration, and pH media. Finally, cyclic tests implied that the synthesized Bi-BDC MOF had good stability and reusability.

This paper presents a dual-circularly polarized (dual-CP) antenna with simple configuration, low-profile, and wide bandwidth. Its primary radiating element is an aperture-coupled patch loaded with a stacked patch for a wide operational bandwidth. A single-section hybrid coupler is utilized as a feeding structure of the antenna to generate dual-CP radiation. Different from the priors normally requiring both wideband radiator and wideband feeding structure, this work demonstrates that the wideband dual-CP radiation can be obtained by combining a wideband radiator and a conventional hybrid coupler. A design operating at the center frequency of 5.5 GHz has been fabricated and tested. The measurements result in a −10-dB reflection coefficient bandwidth of 30.0% (4.66 – 6.31 GHz), a 10-dB isolation bandwidth of 30.9% (4.66 – 6.35 GHz), a 3-dB axial ratio (AR) bandwidth of 29.1% (4.70 – 6.30 GHz), and a realized broadside gain of 5.5 – 7.05 dBic. For a more robust dual-CP radiation, a low-sidelobe 4 $\times $ 4 element array of the proposed antenna has been designed, fabricated, and measured. Compared to the single element design, the array prototype yields similar impedance and 3-dB AR bandwidths, but a higher isolation. The measurements on the array prototype result in an isolation of $\geq 14$ dB, a peak gain of 16.3 dBic, a side-lobe level of $\leq -20$ dB, and a cross-polarization of $\leq -16$ dB across the frequency range of 4.7 – 6.3 GHz (29.1%).

Objective: This paper assesses the relationship between demographics, health parameters, and functional limitations among older adults in Korea, including limitations in activities of daily living (ADLs) and instrumental activities of daily living (IADLs).Methods: We analyzed data from the Korean Longitudinal Study of Aging survey in 2020 and included only participants aged 65 and older. Multinomial logistic regression models were conducted to evaluate the factors that predicted functional limitations.Results: The prevalence of at least one ADL and IADL limitations were 6.14% (severe 1.94% and moderate 4.20%) and 15.49% (severe 3.11% and moderate 12.38%), respectively. People aged 85 and older had high rates of severe disability with 7.37% for ADLs and 12.06% for IADLs. High rates also occurred among people with low education, underweight, physical inactivity, depression, and three or more chronic diseases.Conclusion: Factors associated with functional limitations were age, educational status, body mass index, physical activity, depression, and chronic diseases. To prevent and improve functional limitations in the older populations, active and applicable interventions should be considered for modifiable factors such as physical activity, depression, and abnormal weight.

We investigated the hydrogen gas sensors based on AlGaN/GaN high electron mobility transistors (HEMTs) for high temperature sensing operation. The gate area of the sensor was functionalized using a 10 nm Pd catalyst layer for hydrogen gas sensing. A thin WO3 layer was deposited on top of the Pd layer to enhance the sensor selectivity toward hydrogen gas. At 200 °C, the sensor exhibited high sensitivity of 658% toward 4%-H2, while exhibiting only a little interaction with NO2, CH4, CO2, NH3, and H2S. From 150 °C to 250 °C, the 10 ppm hydrogen response of the sensor was at least eight times larger than other target gases. These results showed that this sensor is suitable for H2 detection in a complex gas environment at a high temperature.

This study aimed to synthesize alumina from an inorganic aluminum nitrate precursor in various binary solvent systems of ethanol and water using the sol-gel self-assembly (SSA) method, employing a triblock copolymer, pluronic P123, as the pore-directing agent. The resulting materials were implemented as a support for the cobalt (Co) catalyst in a methane dry reforming (MDR) reaction at 1073 K under 1 atm. Regardless of the water percentage used in the support synthesis, the methane dry reforming reaction over Co catalysts on alumina supports showed the negligible change in conversion during the 12 h reaction. Moreover, there was evidence of large quantities of amorphous carbon and graphitic carbon on the spent catalyst surface. However, the low oxidation temperature of these deposited carbons could help maintain the balance between the carbon formation and the carbon elimination processes on the catalyst surface during the reforming reaction, hence prolonging the lifetime of the catalyst. The high conversion of methane (CH4) from 64.6% to 82.8% and carbon dioxide (CO2) from 70.7% to 86.6% for the MDR reaction over the as-prepared alumina-supported Co catalyst demonstrated a significant improvement in catalyst production for the MDR reaction from the viewpoint of large-scale applications.

In the Mekong Delta of Vietnam, poultry farmers use high amounts of antimicrobials, but little is known about the drivers that influence this usage. We aimed to identify these drivers using a novel approach that combined participatory epidemiology (PE) and Q-sorting (a methodology that allows the analysis of the subjectivity of individuals facing a common phenomenon). A total of 26 semi-structured collective interviews were conducted with 125 farmers representative of the most common farming systems in the area (chickens, meat ducks, and mobile grazing ducks), as well as with 73 farmers' advisors [veterinarians, veterinary drug shop owners, and government veterinarians/commune animal health workers (CAHWs)] in five districts of Dong Thap province (Mekong Delta). Through these interviews, 46 statements related to the antimicrobials' perceived reliability, costs, and impact on flock health were created. These statements were then investigated on 54 individuals (28 farmers and 26 farmers' advisors) using Q-sorting interviews. Farmers generally indicated a higher propensity for antimicrobial usage (AMU) should their flocks encounter bacterial infections (75.0–78.6%) compared with viral infections (8.3–66.7%). The most trusted sources of advice to farmers were, in decreasing order: government veterinarian/CAHWs, their own knowledge/experience, veterinary drug shop owners, and sales persons from pharmaceutical and feed companies. The highest peak of AMU took place in the early phase of the production cycle. Farmers and their advisors showed considerable heterogeneity of attitudes with regards to AMU, with, respectively, four and three discourses representing their views on AMU. Overall, farmers regarded the cost of AMU cheaper than other disease management practices implemented on their farms. However, they also believed that even though these measures were more expensive, they would also lead to more effective disease prevention. A key recommendation from this finding would be for the veterinary authorities to implement long-term sustainable training programs aiming at reducing farmers' reliance on antimicrobials.

We investigated the sensing characteristics of NO2 gas sensors based on Pd-AlGaN/GaN high electron mobility transistors (HEMTs) at high temperatures. In this paper, we demonstrated the optimization of the sensing performance by the gate bias, which exhibited the advantage of the FET-type sensors compared to the diode-type ones. When the sensor was biased near the threshold voltage, the electron density in the channel showed a relatively larger change with a response to the gas exposure and demonstrated a significant improvement in the sensitivity. At 300 °C under 100 ppm concentration, the sensor’s sensitivities were 26.7% and 91.6%, while the response times were 32 and 9 s at VG = 0 V and VG = −1 V, respectively. The sensor demonstrated the stable repeatability regardless of the gate voltage at a high temperature.

The parameters of electrical network modes do not correspond the requirements GOST 32144-2013 of Russian and the National technical regulation of Vietnam. In real operating conditions in electrical networks in non-sinusoidal and unbalanced modes there are harmonic components of voltages and currents as well as voltages and currents of negative sequence. They cause additional losses of active power, which leads to additional heating and causes premature aging of the insulation, and as the result, the reduction in the service life of induction motors. Currently, we see that the process of formation of intelligent electrical power systems is underway. Systems for continuous monitoring of power quality indices and parameters of electrical systems modes are being developed. These systems can be supplemented with programs for calculating characteristics that issue the warning when the unfavorable influence of the parameters of non-sinusoidal and unbalanced modes is detected on various electrical equipment of both electrical power systems and consumers of electrical energy. The paper provides an overview of the characteristics used to analyze, assess and predict the influence of poor power quality associated with non-sinusoidal and unbalanced of currents and voltages on induction motors. A computer program was developed to calculate these characteristics. The program was used to study the influence of non-sinusoidal and unbalanced modes on the induction motors of the coal sorting plant of the Vietnamese company “Cua Ong-Vinacomin”.

A series of biocompatible high-porosity (up to 72.4%) TiZr-based porous bulk metallic glass (BMG) scaffolds were successfully fabricated by hot pressing a mixture of toxic element-free TiZr-based BMG powder and an Al particle space holder. The morphology of the fabricated scaffolds was similar to that of human bones, with pore sizes ranging from 75 to 250 μm. X-ray diffraction patterns and transmission electron microscopy images indicated that the amorphous structure of the TiZr-based BMG scaffolds remained in the amorphous state after hot pressing. Noncytotoxicity and extracellular calcium deposition of the TiZr-based BMG scaffolds at porosities of 32.8%, 48.8%, and 64.0% were examined by using the direct contact method. The results showed that the BMG scaffolds possess high cell viability and extracellular calcium deposition with average cell survival and deposition rates of approximately 170.1% and 130.9%, respectively. In addition, the resulting TiZr-based BMG scaffolds exhibited a considerable reduction in Young’s moduli from 56.4 to 2.3 GPa, compressive strength from 979 to 19 MPa, and bending strength from 157 MPa to 49 MPa when the porosity was gradually increased from 2.0% to 72.4%. Based on the aforementioned specific characteristics, TiZr-based BMG scaffolds can be considered as potential candidates for biomedical applications in the human body.

Despite the fact that nanocarriers as drug delivery systems overcome the limitation of chemotherapy, the leakage of encapsulated drugs during the delivery process to the target site can still cause toxic effects to healthy cells in other tissues and organs in the body. Controlling drug release at the target site, responding to stimuli that originated from internal changes within the body, as well as stimuli manipulated by external sources has recently received significant attention. Owning to the spherical shape and porous structure, dendrimer is utilized as a material for drug delivery. Moreover, the surface region of dendrimer has various moieties facilitating the surface functionalization to develop the desired material. Therefore, multi-stimuli-responsive dendrimers or ‘smart’ dendrimers that respond to more than two stimuli will be an inspired attempt to achieve the site-specific release and reduce as much as possible the side effects of the drug. The aim of this review was to delve much deeper into the recent progress of multi-stimuli-responsive dendrimers in the delivery of anticancer drugs in addition to the major potential challenges.

Remote sensing is a useful technique to determine spatial variations in crop growth while crop modelling can reproduce temporal changes in crop growth. In this study, we formulated a hybrid system of remote sensing and crop modelling based on a random-effect model and the empirical Bayesian approach for parameter estimation. Moreover, the relationship between the reflectance and the leaf area index was incorporated into the statistical model. Plant growth and ground-based canopy reflectance data of paddy rice were measured at three study sites in South Korea. Spatiotemporal vegetation indices were processed using remotely-sensed data from the RapidEye satellite and the Communication Ocean and Meteorological Satellite (COMS). Solar insulation data were obtained from the Meteorological Imager (MI) sensor of the COMS. Reanalysis of air temperature data was collected from the Korea Local Analysis and Prediction System (KLAPS). We report on a statistical hybrid approach of crop modelling and remote sensing and a method to project spatiotemporal crop growth information. Our study results show that the crop growth values predicted using the hybrid scheme were in statistically acceptable agreement with the corresponding measurements. Simulated yields were not significantly different from the measured yields at p = 0.883 in calibration and p = 0.839 in validation, according to two-sample t tests. In a geospatial simulation of yield, no significant difference was found between the simulated and observed mean value at p = 0.392 based on a two-sample t test as well. The fabricated approach allows us to monitor crop growth information and estimate crop-modelling processes using remote sensing data from various platforms and optical sensors with different ground resolutions.

The parameters of electrical network modes often do not meet the requirements of Russian GOST 32144-2013 and the guidelines of Vietnam. In the actual operating conditions while there is the non-sinusoidal mode in electrical networks voltage and current harmonics are present. Harmonics result in overheating and damage of power transformers since they cause additional active power losses. Additional losses lead to the additional heat release, accelerating the process of insulating paper, transformer oil and magnetic structure deterioration consequently shortening the service life of a power transformer. In this regard there arises a need to develop certain scientific methods that would help demonstrate that low power quality, for instance could lead to a decrease in the electrical equipment service life. Currently we see a development of automated systems for continuous monitoring of power quality indices and mode parameters of electrical networks. These systems could be supplemented by characteristics calculating programs that give out a warning upon detection of the adverse influence of voltage and current harmonics on various electrical equipment of both electric power providers and electric power consumers. A software program presented in the article may be used to predict the influence of voltage and current harmonics on power transformers.

A rapid, sensitive, and selective method for determination of thorium based on the complex with ortho-ester tetra-azophenylcalix[4]arene (TEAC) was described. In the presence of pH of 4–6, TEAC-Th(IV) complex is extracted from an acidic aqueous solution into chloroform layer. The absorbance intensity of complex was measured by UV-Vis spectrometer at 525 nm and the molar absorptivity was found to be 2.4 × 104. Beer’s law was obeyed in the range of 1.0 to 25 × 10−5 M thorium(IV). The effects of pH, TEAC concentration, and shaking time were also studied. The tolerance limits for several metal ions were calculated. The proposed method was applied to the determination of thorium in synthetic solution and in the monazite sand samples with good results.

The electrical equipment operation is cost-effective and reliable when operating parameters of the electrical network correspond to the rated data of the equipment. The real operation conditions, however, differ from those required for electrical equipment, which negatively affects its efficiency. The non-sinusoidal conditions in electrical networks are currently very common. The paper provides an overview of the characteristics obtained from an analysis of publications, which are used to evaluate the effect of the non-sinusoidal conditions on power transformers. The results of the calculation of these characteristics for a transformer installed at a railway traction substation are presented. Parameters of the non-sinusoidal conditions are obtained as a result of measurements.

An adsorbent called chitosan coated magnetic hydroxyapatite nanoparticles (CS-MHAP) was prepared with the purpose of improvement for the removal of Ni2+ ions and textile dye by coprecipitation. Structure and properties of CS-MHAP were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and vibrating sample magnetometer (VSM). Weight percent of chitosan was investigated by thermal gravimetric analysis (TGA). The prepared CS-MHAP presents a significant improvement on the removal efficiency of Ni2+ ions and reactive blue 19 dye (RB19) in comparison with chitosan and magnetic hydroxyapatite nanoparticles. Moreover, the adsorption capacities were affected by several parameters such as contact time, initial concentration, adsorbent dosage, and initial pH. Interestingly, the prepared adsorbent could be easily recycled from an aqueous solution by an external magnet and reused for adsorption with high removal efficiency.

Three composite sponges were made with 10% of curcumin and by using polymers, namely, chitosan and gelatin with various ratios. The chemical structure and morphology were evaluated by FTIR and SEM. These sponges were evaluated for water absorption capacity, antibacterial activity, in vitro drug release, and in vivo wound healing studies by excision wound model using rabbits. The in vivo study presented a greater wound closure in wounds treated with curcumin-composite sponge than those with composite sponge without curcumin and untreated group. These obtained results showed that combination of curcumin, chitosan and gelatin could improve the wound healing activity in comparison to chitosan, and gelatin without curcumin.

This article describes data on eco-shrimp farming households in Ca Mau, Vietnam. The survey was conducted in Tam Giang Dong commune, Nam Can district, Ca Mau province from March 2023 to May 2023 with a total of 120 households engaged in eco-shrimp farming. The non-probability convenience sampling method was used to select respondents. Two responses were removed from the dataset due to uncomplete questionnaires. The dataset includes a structured questionnaire with 52 questions, along with a raw data file of 118 responses. The questionnaire collected data on (a) household demographic information, (b) eco-shrimp farming area and pond types, (c) production characteristics for the 2021-2022 eco-shrimp crop, and (d) farmers' perspectives on the eco-shrimp farming model. The dataset is available in an Excel file format. It is expected to benefit policymakers and local authorities by providing evidence-based insights into the eco-shrimp production model and the compliance of eco-shrimp farmers with mangrove conservation policies., (© 2024 The Author(s).)

Antimicrobials are a core aspect of most livestock production systems, especially in low-and middle-income countries. They underpin the efficient use of scarce feed resources and stabilize returns on capital and labor inputs. Antimicrobial use (AMU) contributes to the production of healthy animals, yet AMU in livestock is linked to antimicrobial resistance (AMR) in animals, humans and the environment. The Vietnamese Platform for Antimicrobial Reduction in Chicken Production was implemented during 2016-2019 and was one of Southeast Asia's first interventions focused on AMU reductions in livestock production. The project targeted small-scale commercial poultry farms in the Mekong Delta region of Vietnam using a "randomized before-and-after controlled" study design. It provided farmers with a locally adapted support service (farmer training plan, advisory visits, biosecurity, and antimicrobial replacement products) to help them reduce their reliance on antimicrobials. A partial budget analysis was performed comparing the control group (status-quo) and intervention group (alternative). The median net farm-level benefit of the intervention strategies with the project's support was VND 6.78 million (interquartile range (IR) VND -71.9-89 million) per farm. Without project support the benefit was reduced to VND 5.1 million (IR VND -69.1-87.2 million) to VND 5.3 million (IR -VND 68.9-87.5 million) depending on the antimicrobial alternative product used. At the project level with a focus on AMU and its reduction, subsequently influence on the resistance reduction, our results showed that achieving resistance reduction benefits with the current knowledge and technologies required investment of at least VND 9.1 million (US$ 395.10) per farm during the project's lifetime. The results highlight the positive net profit for the majority of enrolled farms and a reasonable investments from the project. The recommendation focuses on the implementation of policies on financial support, legislation, and information as potential solutions to facilitate the application of intervention strategies to reduce AMU in poultry production., Competing Interests: All authors declare no conflict of interest., (© 2024 The Authors.)

An innovative p-n heterojunction Bi 2 S 3 /ZnCo 2 O 4 composite was first fabricated via a two-step co-precipitation and hydrothermal method. By controlling the weight amount of Na 2 S and Bi(NO 3 ) 3 precursor, different heterogeneous x Bi 2 S 3 /ZnCo 2 O 4 were synthesized ( x = 0, 2, 6, 12, and 20). The p-n heterojunction Bi 2 S 3 /ZnCo 2 O 4 was characterized by structural, optical, and photochemical properties and the photocatalyst decoloration of indigo carmine. Mott-Schottky plots proved a heterojunction formed between n-Bi 2 S 3 and p-ZnCo 2 O 4 . Furthermore, the investigation of the photocurrent response indicated that the Bi 2 S 3 /ZnCo 2 O 4 composite displayed an enhanced response, which was respectively 4.6 and 7.3 times (4.76 μA cm -2 ) greater than that of the pure Bi 2 S 3 (1.02 μA cm -2 ) and ZnCo 2 O 4 (0.65 μA cm -2 ). Especially the optimized p-n Bi 2 S 3 /ZnCo 2 O 4 heterojunction with 12 wt% Bi 2 S 3 showed the highest photocatalyst efficacy of 92.1% at 40 mg L -1 solutions, a loading of 1.0 g L -1 , and a pH of 6 within 90 min of visible light illumination. These studies prove that p-n Bi 2 S 3 /ZnCo 2 O 4 heterojunction photocatalysts can greatly boost their photocatalytic performance because the inner electric field enhances the process of separating photogenerated electron-hole pairs. Furthermore, this composite catalyst showed good stability and recyclability for environmental remediation., Competing Interests: The authors declare that they have no known competing interests that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Vietnam is a low- and middle-income country (LMIC), a primary food producer, and an antimicrobial resistance (AMR) hotspot. AMR is recognized as a One Health challenge since it may transfer between humans, animals and the environment. This study aimed to apply systematic review and meta-analysis to investigate the phenotypic profiles and correlations of antimicrobial-resistant Enterobacteriaceae across three compartments: humans, animals and the environment in Vietnam. A total of 89 articles found in PubMed, Science Direct, and Google Scholar databases were retrieved for qualitative synthesis. E. coli and non-typhoidal Salmonella (NTS) were the most common bacterial species in studies of all compartments (60/89 studies). Among antimicrobials classified as critically important, the resistance levels were observed to be highest to quinolones, 3rd generation of cephalosporins, penicillins, and aminoglycosides. Of 89 studies, 55 articles reported the resistance prevalence of E. coli and NTS in healthy humans, animals and the environment against ciprofloxacin, ceftazidime, ampicillin, gentamicin, sulfamethoxazole-trimethoprim, chloramphenicol was used for meta-analysis. The pooled prevalence was found highest in E. coli against ampicillin 84.0% (95% CI 73.0-91.0%) and sulfamethoxazole-trimethoprim 66.0% (95% CI 56.0-75.0%) while in NTS they were 34.0% (95% CI 24.0-46.0%), 33.0% (95% CI 25.0-42.0%), respectively. There were no significant differences in the pooled prevalence of E. coli and NTS to these antimicrobials across healthy humans, animals and the environment, except for ceftazidime-resistant E. coli (χ 2  = 8.29, p  = 0.02), chloramphenicol-resistant E.coli (χ 2  = 9.65, p  < 0.01) and chloramphenicol-resistant NTS (χ 2  = 7.51, p = 0.02). Findings from the multiple meta-regression models indicated that the AMR levels in E. coli (β = 1.887, p  < 0.001) and the North (β = 0.798, p  = 0.047) had a higher fraction of AMR than NTS and other regions of Vietnam. The outcomes of this study play an important role as the baseline information for further investigation and follow-up intervention strategies to tackle AMR in Vietnam, and more generally, can be adapted to other LMICs., Competing Interests: All authors declare no conflict of interest., (Crown Copyright © 2022 Published by Elsevier B.V.)

Colistin is extensively used in animal production in many low- and middle-income countries. There is a need to develop methodologies to benchmark and monitor changes in resistance among mixed commensal bacterial populations in farms. We aimed to evaluate the performance of a broth microdilution method based on culturing a pooled Escherichia coli suspension (30-50 organisms) obtained from each sample. To confirm the biological basis and sensitivity of the method, we cultured 16 combinations of one colistin-susceptible and one mcr -1 encoded colistin-resistant E. coli in the presence of 2mg/L colistin. Optical density (OD 600nm ) readings over time were used to generate a growth curve, and these values were adjusted to the values obtained in the absence of colistin (adjusted Area Under the Curve, AUC adj ). The median limit of detection was 1 resistant in 10 4 susceptible colonies [1 st - 3 rd quartile, 10 2 :1 -10 5 :1]. We applied this method to 108 pooled faecal samples from 36 chicken flocks from the Mekong Delta (Vietnam), and determined the correlation between this method and the prevalence of colistin resistance in individual colonies harvested from field samples, determined by the Minimum Inhibitory Concentration. The overall prevalence of colistin resistance at sample and isolate level (estimated from the AUC adj ) was 38.9% [95%CI, 29.8-48.8%] and 19.4% (SD± 26.3%), respectively. Increased colistin resistance was associated with recent (2 weeks) use of colistin (OR=3.67) and other, non-colistin antimicrobials (OR=1.84). Our method is a sensitive and affordable approach to monitor changes in colistin resistance in E. coli populations from faecal samples over time. IMPORTANCE Colistin (polymyxin E) is an antimicrobial with poor solubility in agar-based media, and therefore broth microdilution is the only available method for phenotypic resistance. However, estimating colistin resistance in mixed Escherichia coli populations is laborious since it requires individual colony isolation, identification and susceptibility testing. We developed a growth-based microdilution method suitable for pooled faecal samples. We validated the method by comparing it with individual MIC of 909 E. coli isolates; we then tested 108 pooled faecal samples from 36 healthy chicken flocks collected over their production cycle. A higher level of resistance was seen in flocks recently treated with colistin in water, although the observed generated resistance was short-lived. Our method is affordable, and may potentially be integrated into surveillance systems aiming at estimating the prevalence of resistance at colony level in flocks/herds. Furthermore, it may also be adapted to other complex biological systems, such as farms and abattoirs., (Copyright © 2020 Nguyen et al.)

The accurate assessment of antimicrobial use (AMU) requires relating quantities of active ingredients (AAIs) with population denominators. These data can be used to prioritize potential sources of selective pressure for antimicrobial resistance and to establish reduction targets. Here, we estimated AMU in Vietnam (human population 93.4 M in 2015), and compared it with European Union (EU) data (population 511.5 M in 2014). We extrapolated AMU data on each key animal species and humans from different published sources to calculate overall AMU (in tonnes) in Vietnam. We then compared these data with published statistics on AMU in the European Union (EU). A total of 3838 t of antimicrobials were used in Vietnam, of which 2751 (71.7%) corresponded to animal use, and the remainder (1086 t; 28.3%) to human AMU. This equates to 261.7 mg and 247.3 mg per kg of human and animal biomass, compared with 122.0 mg and 151.5 mg in the EU. The greatest quantities of antimicrobials (in decreasing order) were used in pigs (41.7% of total use), humans (28.3%), aquaculture (21.9%) and chickens (4.8%). Combined AMU in other species accounted for < 1.5%. These results are approximate and highlight the need to conduct targeted surveys to improve country-level estimates of AMU., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s). 2020.)

Background: The Mekong Delta of Vietnam is a hotspot of antimicrobial use (AMU), but there is no information on the quality of the labelling and strength of antimicrobial products used in poultry production., Methods: Based on a large random sample of farms, we identified the 20 most used antimicrobial products in the area, and investigated their antimicrobial active ingredient (AAI) content by UPLC-MS/MS (91 analytical tests)., Results: Only 17/59 (28.8%) batches contained all AAIs within 10% of the declared strength. Worryingly, 65.0% products provided in their label preparation guidelines for both therapeutic and prophylactic use. Withdrawal times for both meat and eggs were stated in 8/20 (40%) products., Conclusion: Results highlight deficiencies in quality and labelling contents that undermine authorities' efforts to discourage inappropriate use of antimicrobials., (© 2019 The Authors. Veterinary Medicine and Science Published by John Wiley & Sons Ltd.)

Cross-species transmission of viruses poses a sustained threat to public health. Due to increased contact between humans and other animal species the possibility exists for cross-species transmissions and ensuing disease outbreaks. By using conventional PCR amplification and next generation sequencing, we obtained 130 partial or full genome kobuvirus sequences from humans in a sentinel cohort in Vietnam and various mammalian hosts including bats, rodents, pigs, cats, and civets. The evolution of kobuviruses in different hosts was analysed using Bayesian phylogenetic methods. We estimated and compared time of origin of kobuviruses in different host orders; we also examined the cross-species transmission of kobuviruses within the same host order and between different host orders. Our data provide new knowledge of rodent and bat kobuviruses, which are most closely related to human kobuviruses. The novel bat kobuviruses isolated from bat roosts in Southern Vietnam were genetically distinct from previously described bat kobuviruses, but closely related to kobuviruses found in rodents. We additionally found evidence of frequent cross-species transmissions of kobuviruses within rodents. Overall, our phylogenetic analyses reveal multiple cross-species transmissions both within and among mammalian species, which increases our understanding of kobuviruses genetic diversity and the complexity of their evolutionary history.

Antimicrobials are extensively used as growth promoters in animal feeds worldwide, but reliable estimates are lacking. We conducted an internet-based survey of commercial chicken and pig feed products officially approved for sale in Vietnam over the period March-June 2015. Information on the antimicrobial contents in feed products, alongside animal production data, was used to estimate in-feed antimicrobial consumption to produce one kilogram of live animal (chicken, pig), as well as to estimate country-wide antimicrobial consumption through animal feeds. A total of 1462 commercial feed formulations were examined. The survey-adjusted estimated antimicrobial contents were 25.7 and 62.3 mg/kg in chicken and pig feeds, respectively. Overall, it was estimated that 77.4 mg [95% CI 48.1-106.8] and 286.6 mg [95% CI 191.6-418.3] of in-feed antimicrobials were used to raise 1 kg of live chicken and pig, respectively. Bacitracin (15.5% feeds), chlortetracycline (11.4%), and enramycin (10.8%) were the most common antimicrobials present in chicken feed formulations, whereas bacitracin (24.8%), chlortetracycline (23.9%), and florfenicol (17.4%) were the most common in pig feed formulations. Overall, 57% of the total quantitative usage consisted of antimicrobials regarded by WHO of importance for human medicine, including amoxicillin, colistin, tetracyclines, neomycin, lincomycin, and bacitracin. These figures confirm a very high magnitude of in-feed consumption of antimicrobials, especially in pig production. Results from this study should encourage further monitoring of antimicrobials used in animal production, and foster discussion about existing policies on inclusion of antimicrobials in animal feed rations., Competing Interests: The authors declare that they have no conflict of interest.

Members of the Picornaviridae are important and often zoonotic viruses responsible for a variety of human and animal diseases. However, the evolution and spatial dissemination of different picornaviruses circulating in domestic animals are not well studied. We examined the rate of evolution and time of origin of porcine enterovirus G (EV-G) and porcine kobuvirus species C lineages (PKV-C) circulating in pig farms in Vietnam and from other countries. We further explored the spatiotemporal spread of EV-G and PKV-C in Southwest Vietnam using phylogeographic models. Multiple types of EV-G are co-circulating in Vietnam. The two dominant EV-G types among isolates from Vietnam (G1 and G6) showed strong phylogenetic clustering. Three clades of PKV-C (PKV-C1-3) represent more recent introductions into Vietnam; PKV-C2 is closely related to PKV-C from Southwest China, indicating possible cross-border dissemination. In addition, high virus lineage migration rates were estimated within four districts in Dong Thap province in Vietnam for both EV-G types (G1, G6) and all PKV-C (C1-3) clades. We found that Chau Thanh district is a primary source of both EV-G and PKV-C clades, consistent with extensive pig trading in and out of the district. Understanding the evolution and spatial dissemination of endemic picornaviruses in pigs may inform future strategies for the surveillance and control of picornaviruses.

A recent survey of pigs in Dong Thap province, Vietnam identified a high frequency of enterovirus species G (EV-G) infection (144/198; 72.7%). Amongst these was a plethora of EV-G types (EV-G1, EV-G6 and four new types EV-G8-EV-G11). To better characterize the genetic diversity of EV-G and investigate the possible existence of further circulating types, we performed a larger-scale study on 484 pig and 45 farm-bred boar faecal samples collected in 2012 and 2014, respectively. All samples from the previous and current studies were also screened for kobuviruses. The overall EV infection frequency remained extremely high (395/484; 81.6%), but with comparable detection rates and viral loads between healthy and diarrhoeic pigs; this contrasted with less frequent detection of EV-G in boars (4/45; 8.9%). EV was most frequently detected in pigs ≤ 14 weeks old (∼ 95%) and declined in older pigs. Infections with EV-G1 and EV-G6 were most frequent, whilst less commonly detected types included EV-G3, EV-G4 and EV-G8-EV-G11, and five new types (EV-G12-EV-G16). In contrast, kobuvirus infection frequency was significantly higher in diarrhoeic pigs (40.9 versus 27.6%; P = 0.01). Kobuviruses also showed contrasting epizootiologies and age associations; a higher prevalence was found in boars (42%) compared with domestic pigs (29%), with the highest infection frequency amongst pigs >52 weeks old. Although genetically diverse, all kobuviruses identified belonged to the species Aichivirus C. In summary, this study confirms infection with EV-G was endemic in Vietnamese domestic pigs and exhibits high genetic diversity and extensive inter-type recombination.

New complexes of 5,11,17,23-tetra[(2-ethyl acetoethoxyphenyl)(azo)phenyl]calix[4]arene (TEAC) with Pb(II) and Cr(III) were prepared in basic solution with a mixture of MeOH and H2O as solvent. The ratio of TEAC and metal ion in complexes was found to be 1 : 1 under investigated condition. The complex formation constants (based on Benesi-Hildebrand method) for TEAC-Pb(II) and TEAC-Cr(III) were 4.03 × 10(4) and 1.2 × 10(4), respectively. Additionally, the molar extinction coefficients were 5 × 10(4) and 1.42 × 10(4) for TEAC-Pb(II) and TEAC-Cr(III), respectively. The H-Point Standard Addition Method (HPSAM) has been applied for simultaneous determination of complexes formation of Cr(III)/Pb(II) and TEAC with concentration from 2 : 1 to 1 : 20 (w/w). The proposed method was successfully utilized to invest lead and chromium contents in plating wastewater samples. The results for several analyzed samples were found to be in satisfied agreement with those acquired by using the inductively coupled plasma mass spectrometry (ICP-MS) technique.

Objective: To study the impact on measles case incidence of a nationwide measles immunization campaign in Viet Nam, while considering differences in disease surveillance before and after the campaign., Methods: A nationwide mass immunization campaign was conducted in the north and south of Viet Nam in 2002 and 2003, respectively. During the campaign, a second vaccination dose was given to children aged 9 months to 9 years, and the reported coverage reached 99% in both zones. National measles case-based surveillance data collected during 2001-2006 were reviewed and analysed. Surveillance performance was assessed in terms of case investigation and specimen collection rates and reporting sensitivity for febrile rash cases. Fisher's exact test was used to test for differences in indicator values before and after the campaign at the national and regional levels; the Wilcoxon signed-rank test was used at the provincial level., Findings: Despite significant improvements in disease surveillance, a dramatic reduction in observed measles incidence was noted nationwide after the immunization campaign, with a drop in the national incidence of confirmed measles cases per 100 000 population from 5.44 in 2001 to 0.14 after the campaign (i.e. 2003 in the north and 2004 in the south; P < 0.001). Rapid measles resurgence was observed in 2005 and 2006 only in the north-western mountainous region of the country. The north did not show a statistically significant age shift for new cases (median age: 9 years in 2001 versus 8 years in 2003; P = 0.113), whereas the south did (median age: 7 years versus 12 years; P < 0.001)., Conclusion: A campaign approach for controlling measles in developing parts of Asia can prove effective. The swift re-emergence of disease in the north-western region was probably due to suboptimal coverage by the campaign and by the subsequent routine expanded programme on immunization in the north-western mountainous region.