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چکیده انسان علاقهمند به کشف ناشناختههاست، میخواهد بداند در پی حوادث و پدیدههای جهان چه نیرویی و چه عواملی قرار دارد، میخواهد بداند ماهیت اشیاء و پدیدهها و ویژگیهای ها آن چیسـت و روابـط ها آن با یکدیگر چگونه است؛ همچنین تفکر خلاق به طور بالقوه و به نحو فطری در انسـان بـه ودیعـه نهاده شده و از طرفی یکـی از اهـداف پژوهشسـراهای دانـش آمـوزی تقویـت حـلّ خـلاق مسـئله در دانشآموزان است و مقالۀ حاضر مقایسۀ فرایند حل خلاق مسئله را در بین دانشآموزان دورة متوسـطۀ عضو و غیرعضو پژوهشسراها مورد بررسی قرار داده است. این پژوهش از نوع تحقیقات نیمـه تجربـی (شبه تجربی) و روش آن آزمایشی است. (طرح آزمون مقدماتی و نهایی با گروه شاهد و بدون اسـتفاده از گزینش تصادفی) و ابزار جمعآوری دادهها پرسشنامه فراینـد حـل خـلاق مسـئله اسـت و سـرانجام براساس محاسبات از طریق تحلیل کواریانس میانگین نمرات حل خلاق مسـئله در بـین دانـش آمـوزان گروه آزمایش و شاهد تفاوت معنیدار است که حکایـت از تـأثیر برنامـه هـا و فعالیـت هـای پژوهشـی پژوهشسراها بر فرایند حل خلاق مسئله در بین دانشآمـوزان عضـو پژوهشسـراها دارد؛ زیـرا مقایسـۀ میانگینها نشان میدهد که نمرات گروه آزمایش بالاتر از گروه شاهد است ؛ در نتیجه ، لازم است نسبت به تقویت پژوهشسراهای دانشآموزی برای نیل به اهداف خود تلاش بیشتری صورت گیرد

We report a microscopic study of p-GaAs/TiO2 heterojunctions using cross-sectional high resolution transmission electron microscopy (HRTEM). The photocatalytic performance for both H2 evolution and CO2 reduction of these heterostructures shows a very strong dependence on the thickness of the TiO2 over the range of 0-15 nm. Thinner films (1-10 nm) are amorphous and show enhanced catalytic performance with respect to bare GaAs. HRTEM images and electron energy loss spectroscopy (EELS) maps show that the native oxide of GaAs is removed by the TiCl4 atomic layer deposition (ALD) precursor, which is corrosive. Ti3+ defect states (i.e., O vacancies) in the TiO2 film provide catalytically active sites, which improve the photocatalytic efficiency. Density functional theory (DFT) calculations show that water molecules and CO2 molecules bind stably to these Ti3+ states. Thicker TiO2 films (15 nm) are crystalline and have poor charge transfer due to their insulating nature, while thinner amorphous TiO2 films are conducting.

Lựa chọn nghề nghiệp luôn là một trong những yếu tố quan trọng để dự đoán sự phát triển bền vững trong tương lai và ảnh hưởng lớn đến cuộc sống, sự nghiệp của sinh viên. Bằng phương pháp phát phiếu khảo sát trực tuyến, nhóm nghiên cứu đã thu thập được 3.849 phiếu trả lời hợp lệ. Áp dụng mô hình lý thuyết nghề nghiệp nhận thức xã hội kết hợp với các phương pháp phân tích số liệu định lượng, bài viết chứng tỏ yếu tố ảnh hưởng đồng trang lứa và ảnh hưởng nhận thức đều có tác động trực tiếp đến lựa chọn nghề nghiệp. Nghiên cứu cũng chứng minh mối quan hệ gián tiếp giữa sự tự tin vào năng lực bản thân và lựa chọn nghề nghiệp thông qua biến kết quả kỳ vọng nghề nghiệp. Bài nghiên cứu góp phần đa dạng hóa các tài liệu về lựa chọn nghề nghiệp và đưa ra khuyến nghị cho chính phủ, doanh nghiệp và sinh viên nhằm tháo gỡ những khó khăn về lao động việc làm và đóng góp vào sự phát triển nghề nghiệp bền vững

Phosphorus pollution poses a significant environmental challenge in wastewater from industries like modified starch production. This study investigates the feasibility of mitigating phosphorus contamination in modified starch production wastewater using calcium and magnesium ions. In the first step, polyaluminum chloride (PAC) alone achieves a phosphorus removal efficiency of 38 % with a dosage of 800 mg/L. Subsequently, in the second step, optimal conditions are achieved at a Ca:P molar ratio of 2.5–3 with a 20-min reaction time, resulting in a remarkable phosphorus removal efficiency of 97 %. The study highlights the critical role of pH adjustment during precipitation reactions and offers insights into efficient phosphorus removal strategies. These findings contribute to sustainable wastewater treatment methodologies, addressing environmental concerns in industrial settings.

In this work, polypyrrole-based nanocomposites doped with graphene oxide, molybdate, and salicylate (PPy/GO/Mo/Sal) were synthesized via in situ electrochemical polymerization to enhance the anti-corrosion protection performance of polymer coatings. The morphology and structures of the coatings were characterized by SEM, EDX, FTIR, Raman spectroscopy, and XRD. The protection abilities of coatings against corrosion were investigated in 0.1 M NaCl solution with EIS potentiodynamic polarization, salt spray test, and open-circuit potential (OCP) measurements. The results showed that with the presence of both molybdate/salicylate and GO in the PPy matrix, the nanocomposite coating exhibited an excellent protection ability against corrosion for low-carbon steel, better than that with only GO as filler. Compared to the nanocomposites doped with only salicylate or salicylate/GO, the one doped with both molybdate/salicylate and GO exhibited the longest protection plateau (ca. 100 h) on the OCP-time curves with some fluctuation points known as the self-healing action of molybdate dopant. It also resulted in a decrease in the corrosion current (Tafel plots), a higher impedance (Bode plot), and a better protection performance in salt spray tests. In this case, the anti-corrosion ability of the coatings was provided through a barrier and self-healing mechanism.

We report on an outbreak of nongroupable Neisseria meningitidis–associated urethritis, primarily among men who have sex with men in southern Vietnam. Nearly 50% of N. meningitidis isolates were resistant to ciprofloxacin. This emerging pathogen should be considered in the differential diagnosis and management of urethritis.

Human beings are frequently exposed to a mixture of chemical pollutants through the ingestion of contaminated drinking water. The present study aimed to assess the ecological and human health risks associated with the contamination of cyanotoxins and heavy metals in a drinking water supply reservoir, the Tri An Reservoir (TAR), in Vietnam. Results demonstrated that the concentrations of individual heavy metals varied in the following order: iron (Fe) > lead (Pb) > arsenic (As) > zinc (Zn). Although the ecological potential risk of heavy metals was low during the study period, the concentration of Fe sometimes exceeded the Vietnamese standard for drinking water. Toxic cyanobacteria and microcystins (MCs) frequently occurred in the TAR with the highest density of 198.7 × 103 cells/mL and 7.8 μg/L, respectively, indicating a high risk of health impacts to humans. The results of the study indicate that exposure to heavy metals does not pose any non-carcinogenic health risks for both adults and children. However, the contamination of MCs in the surface water posed a serious disease enhancement to both adults and children through direct ingestion and dermal absorption. HIGHLIGHTS The ecological and human health risks associated with the contamination of cyanotoxins and heavy metals were investigated.; Water was contaminated with cyanotoxins and iron.; The potential risks of heavy metals were low, but the concentration of cyanotoxins indicated a high risk to human health.; This study highlights the ecological and human risks from exposure to mixtures of pollutants.;

This study developed an antifouling coating for polyethersulfone (PES) membranes by tuning the bandgap of TiO2 with Cu nanoparticles (NPs) via a polyacrylic acid (PAA)-plasma-grafted intermediate layer. Cu NPs were synthesized at different molar ratios and precipitated onto TiO2 using the sol-gel method. The resulting Cu@TiO2 photocatalysts were characterized using various techniques, showing reduced bandgap, particle size range of 100–200 nm, and generation of reactive free radicals under light irradiation. The 25% Cu@TiO2 photocatalyst displayed the highest catalytic efficiency for Acid Blue 260 (AB260) degradation, achieving 73% and 96% with and without H2O2, respectively. Photocatalytic membranes based on this catalyst achieved an AB260 degradation efficiency of 91% and remained stable over five cycles. Additionally, sodium alginate-fouled photocatalytic membranes fully recovered water permeability after undergoing photocatalytic degradation of foulants. The modified membrane displayed a higher surface roughness due to the presence of photocatalyst particles. This study demonstrates the potential application of Cu@TiO2/PAA/PES photocatalytic membranes for mitigating membrane fouling in practice. HIGHLIGHTS Bandgap tuning of TiO2 with Cu NPs successfully enhanced photocatalytic performance.; Mechanism of photocatalytic decomposition of Acid Blue 260 attributed to •OH radicals.; PAA plasma-grafting improved binding between PES membrane surface and photocatalyst.; Cu@TiO2/PAA/PES membranes exhibited high water flux and FRR of 98%.;

Human development is crucial for a country's prosperity, reflecting its economic growth and social progress. This study examines how using renewable energy can boost human development across 77 countries, including high-income and 33 middle-income, from 2000 to 2019. This paper employs the panel-corrected standard error (PCSE) model to generate appropriate outcomes for the existence of heteroscedasticity, serial correlations, and sectional dependencies (CD). The results reveal a positive link between renewable energy adoption and human development across three dimensions-health, education, and income. This connection holds for various renewable sources like hydropower, solar, and wind energy. Additionally, when the research sample is separated into high- and middle-income nations, we find differing impacts of renewable energy on human development dimensions, such as hydro energy has a negative impact on the income dimension in high-income countries; meanwhile, the solar, wind, and hydro energy are insignificant or less pronounced in middle-income countries. This study highlights the importance of renewable energy for human development but emphasizes the need for tailored approaches considering income levels and specific renewable energy sources. Based on findings, theoretical and practical implications have been proposed to promote the use of renewable energy towards sustainable development goals.

The coastal area of Southeast Vietnam is one of the most dynamic regions with rapid development and diverse natural resources. However, it also has a high potential for environmental hazards resulting from chemical incidents during its development process, particularly from industrial zones. In this study, potential environmental exposure resulting from chemical incidents in the coastal region of Southeast Vietnam is analyzed using a combination of remote sensing methods, mathematical modeling, GIS techniques, and index methods. Based on the results of the hazard classification of environmental incidents in the Southeast region, which have been conducted in previous studies by the author group, this study developed typical environmental incident scenarios and simulates the potential environmental exposure level of coastal areas in the event of an environmental incident using the mathematical model MIKE 21. The simulated result values are converted based on the rating scale to determine the Exposure Index and divided into four levels: low, moderate, high, and very high. The simulation and assessment results show that the potential pollution transmission range is lower during the dry season than during the rainy season and is mainly concentrated around the incident area. Of the 27 coastal sub-regions in the study area, 12/27 sub-regions were exposed during the dry season, accounting for 44.44%, and 15–16/27 sub-regions were exposed during the rainy season for 55.56–59.26%. The results of exposure zoning show that the risk of environmental exposure to coastal chemical incidents in the study area is relatively serious and has a wide-ranging impact if there are no timely and effective response measures. These assessment results are expected to contribute to increasing predictability and reducing potential consequences in the event of environmental incidents in the coastal areas of the Southeast region.

Objective: This study aimed to describe the conflict management styles and identify factors affecting the conflict management styles of nurse managers. Materials and Methods: A cross-sectional study was conducted by interviewing nurse managers with a questionnaire, including the Rahim Organizational Conflict Inventory-II Form B, used to assess an individual's approach to conflict management across five styles: cooperating, competing, compromising, obliging, and avoiding. Results: A total of 30 nurse managers participated in this study. The mean scores of the cooperating style were the highest at 4.3 ± 0.4, followed by a compromising style at 3.4 ± 0.5, an avoiding style at 3.1 ± 0.6, an accommodating style at 2.9 ± 0.7, and a competing style at 2.8 ± 0.8 (χ2 = 66.624, P < 0.001). The mean scores for avoiding style among bachelor's degree nurse managers (3.2 ± 0.6) were higher than those of master's degree nurse managers (2.7 ± 0.6) (P = 0.036). Nurse managers over 40 years old, holding a managerial position for ≥10 years, and frequent conflict handling rated higher mean scores for the cooperating style than their counterparts (P < 0.05). Conclusion: The cooperating style was the most commonly used conflict management style among nurse managers. Factors affecting the conflict management style were age, education level, and experience in management and conflict handling. These findings are useful for developing interventions that enhance the competencies of nurse managers in conflict management.

Introduction. Systematic errors of microelectromechanical (MEMS) inertial sensors, such as those related to zero drift, scale factor, and nonorthogonality of sensitive axes, are the main sources of errors in strapdown inertial navigation systems (SINS). Uncompensated sensor errors accumulate over time as motion state errors, thus reducing the overall accuracy of SINS. Consequently, calibration of inertial sensors is a relevant research task. The disadvantage of existing sensor calibration methods consists in a strict requirement for the initial alignment of sensitive sensor axes relative to a reference coordinate system, which complicates the entire process of calibration. Therefore, alternative methods for MEMS sensor calibration should be developed.Aim. To develop a calibration algorithm for microelectromechanical (MEMS) sensors, which allows calibrating sensors regardless of the angular orientation of the sensor axes relative to a reference coordinate system at the initial installation, as well as to simplify the design of testing tools.Materials and methods. Publications in national and international journals on the theory of calibration of inertial sensors were reviewed. A calibration algorithm was developed based on the least squares method.Results. An algorithm for determining the calibration parameters of sensors regardless of the initial alignment of the sensor sensitive axes relative to a reference system was developed. A simple alternative design for testing MEMS sensors was proposed.Conclusion. The method of calibrating MEMS inertial sensors proposed in this work differs from conventional calibration methods by increased reliability of the results and a simplified design of testing tools. Importantly, the results of determining the calibration coefficients of a micromechanical accelerometer (MMA) do not depend on its angular position relative to a geographic coordinate system (GСS). This works contributes to improving the accuracy of SINS based on MEMS inertial sensors.

Fire accidents cause damage and injuries; hence, fire protection is imperative for building construction. Smoke control reduces smoke concentrations as well as the temperature to enable evacuation of building residents. Moreover, firefighters easily extinguish fire with low smoke concentrations and temperatures. In this study, the Fire Research Station, UK standard, was applied to calculate the flow rate of the smoke exhaust fan for a basement with dimensions of 30 m × 20 m × 4 m using a computational fluid dynamic (CFD) code in the transient mode. The model was established by Revit 2020, and the fire simulation was conducted using Autodesk CFD 2020. The fire simulation was analyzed under the total exhaust fan volume values of 20000 m3/h, 50000 m3/h and 100000 m3/h, the air change per hour (ACH) values equivalent to 8.5, 21 and 42.5, respectively. The results reveal that the total exhaust fan volume of 100000 m3/h is optimum because at 1200 s, after the fire, the temperature of the basement is less than 1.4 m is less than 65 °C, and smoke visibility is ∼10 m. Moreover, the amount of smoke escaping through the doors was the lowest. This condition is suitable for evacuation and for firefighters to put out the fire. In addition, a volume of 100000 m3/h was compatible with the formula of the standard. Therefore, Autodesk CFD is also an optimum choice for engineers to verify their design before conducting site work to save time and increase confidence.

The sustainable development of enterprises, which has economic, commercial, ethical, social, and environmental dimensions, is increasingly attracting attention. Focusing on the dimensions of sustainable development is essential in the present day. This study adds to the literature by examining the role of the dimensions of corporate social responsibility (CSR) in employees’ perceptions of the importance of CSR activities for improving brand reputation by enhancing brand equity. A questionnaire was administered to the participants, who were recruited by using a random sampling approach. The target respondents were representatives of Vietnamese enterprises that engage in CSR activities in the course of their management and commercial operations. All data were gathered in Ho Chi Minh City (HCMC), Vietnam, and 417 suitable data samples were selected for analysis. The dimensions of CSR influence internal and external activities at enterprises in HCMC positively. The results indicate that both internal and external CSR activities improve employee satisfaction and that implementing CSR activities supports the enhancement of brand reputation and adds value to brand equity. This study also contributes to and expands the literature on the CSR dimensions of employee satisfaction, which can enhance brand reputation by improving brand equity. Moreover, the study provides valuable insights that may support the managers of Vietnamese enterprises in the adoption of more intensive CSR practices by virtue of focusing on the core values of employee satisfaction and brand management.

Anthracnose caused by Colletotrichum truncatum (C. truncatum) fungus, a seriously damaged in many soybean growing areas, has almost no effective control strategy. Recently, biostimulants for disease prevention of plants have been considered a feasible solution. In this study, the chitinase-induced effect on soybean plants of various oligochitosan-Zn2+ (OC–Zn2+) complexes prepared from gamma radiation-degraded oligochitosans with the different molecular weights (Mw) of 2.5, 5.1, and 7.8 kDa was investigated in the first time. The potted soybean plants in a greenhouse were treated with a foliar spray of OC-Zn2+ solutions at 50 ppm and inoculated with a disease by a fungal spore suspension spray of C. truncatum to assess the chitinase-elicited effect. The chitinase activity (CA) which described in milliunits per gram (mU/g) of fresh leaves in soybean was determined by the optical density measurement method based on the reducing sugar reaction. The obtained results indicated that the OC-Zn2+ complex exhibited a synergistic effect of OC and Zn2+. The OC5.1-Zn2+ complex prepared from the OC with Mw of 5.1 kDa showed a high chitinase-induced effect with the CA ∼12 mU/g. The OC-Zn2+ complexes with effective chitinase inductivity could be feasibly produced on a large scale. Thus, the complexes have been promising to be potentially applied in sustainable agriculture production.

Although in a critical position in the economy, the paper industry releases a lot of wastewater that requires adequate treatment for sustainable development. This study presents an application of Life cycle assessment (LCA) with the ReCiPe tool on the wastewater treatment plant (WWTP) of a paper factory in Vietnam to evaluate the environmental effect of the individual techniques in WWTP, especially the internal circulation (IC) reactor, a pioneer and practical anaerobic technology. Both Midpoint and Endpoint categories results demonstrated that chemical use and electricity consumption mainly contributed to the environmental impact in the WWTP. The Dissolved air flotation (DAF) and Moving bed biofilm reactor (MBBR) are classified as effective techniques to reduce the impacts on the environment. Moreover, the comparison of LCA between IC and up-flow anaerobic sludge bed (UASB) shows that IC is the better practically green technique for the environment. HIGHLIGHTS Life cycle assessment was applied in a paper mill wastewater treatment plant.; Midpoint and Endpoint indicators were employed to evaluate environmental impact.; Two scenarios of electricity generating from biogas between Internal circulation and up-flow anaerobic sludge bed were investigated.; Chemicals use and energy consumption were determined to be the most factors to damage indicators.;

Constructing the 3D objects based on geometric modelling and graphical techniques is a well-known research activity applied in computer graphics. Techniques to process graphical models are widely used in the field of digital heritage and 3D game. Virtual reality (VR) and Augmented Reality (AR) are technical trends nowadays that can be studied and used in digital high-tech fields like medical training, digital heritage, entertainment industry, digital tourism and museum, etc. In this research, we present a new proposed method for reconstructing the 3D objects of tangible cultural heritages in the virtual environment based on the combination of geometric modelling, computer graphics, VR and AR technologies. The method consists of the following steps: we first collect data of a real object by using a 3D scanner. After processing obtained data, the output is a 3D point cloud. In the next step, we remove noisy data and triangulate the object surface. The novelty point focuses on reconstructing the 3D object by filling the holes. At the end, we build VR and AR applications for visualizing a virtual museum. The contribution of this research leads to open the door for applying in other fields such as 3D Game industry or digital tourism.

In developing countries, nitrogen in the traditional market wastewater is a critical environmental problem. In this study, the microalga Chlorella sp., which was isolated from wastewater, was used to remove the total nitrogen (TN) from conventional market wastewater in combination with audible sound (Vietnamese classical music). In addition, effects of sound exposure on removal efficiency at different initial cell densities were analyzed. Results revealed that music sound control demonstrates potential to improve the removal efficiency. TN removal efficiencies of 96%, 69.5%, and 4.3% were observed for treatments with Chlorella sp./audible sound, Chlorella sp., and without Chlorella sp., respectively. The significance of probability value (p-value) (

In this study, the electro-Fenton (EF) method was applied to remove total organic carbon (TOC) from the pesticide production wastewater containing tricyclazole (TC). Statistical Taguchi method was used to optimize the treatment performance. Analysis of variance (ANOVA) indicated that the polynomial regression model fitted experimental data with R2 of 0.969. The optimal conditions for eliminating 75.4% TOC and 93.7% TC were 0.2 mM of Fe2+, 990 mg/L of Na2SO4, 180 min of reaction time at pH 3 with 2.22 mA/cm2 of current density. The removal of TC present in the wastewater followed the first-order reaction kinetic model (R2 = 0.993); while that was the second-order kinetic model in the case of the TOC removal (R2 = 0.903). In addition, the experimental results and theory approaches (density functional theory and natural bond orbital calculations) also showed the C-N bond breaking and nitrate ions cleavage to ammonia. Acute toxicity of the pesticide wastewater after treatment (PWAT) on microcrustaceans showed that the treated wastewater still exhibited high toxicity against D. magna, with LC50 values of 3.84%, 2.68%, 2.05%, and 1.78% at 24 h, 48 h, 72 h, and 96 h, respectively. HIGHLIGHTS Electro-Fenton (EF) was employed to remove TOC and tricylazole from real pesticide wastewater.; Taguchi approach (L27) had been developed on five factors of EF on TOC removal.; ANOVA showed a well-fitted polynomial regression model with R2 of 0.969.; The nitrogen minerals reached 25.3 as explained by DFT/NBO calculations.; Cost analysis, kinetic reaction of EF process and bioassay toxicological test also evaluated.;

The strong growth of communication and storage gives rise to the significantly increasing demand for collecting, storing, and sharing a large amount of data on networks. This is further enhanced by the data-driven market, where everyone wants to access other parties' data. Data is the bedrock of today's technologies and researchers, especially in machine learning and deep learning. The business value of organizations is also massively data-dependent. Recent studies and industry applications can apply analytic techniques for exploiting data, or Internet users can exchange data on social networks or peer-to-peer (P2P) networks. However, sharing secured data is a challenging problem that attracts much attention from researchers. Sharing secure data with a group of users using P2P applications faces the unavailability problem of peer nodes. Thus users cannot certify and download the protected data. This affects a P2P-based application class of sharing and storing online services or customer-to-customer e-commerce applications. This article proposes a solution for sharing secured data on P2P-based applications using blockchain and attribute-based encryption. The attribute-based encryption guarantees sharing keys among a group of users, while blockchain guarantees keys distribution. We have simulated the proposed solution on the mobile peer-to-peer network that provides services for sharing and storing data securely.

In this study, chitosan was prepared from the shell of Somanniathelphusa sinensis, which is a crab ubiquitous in Vietnam. The 3-level, 3-factor Box–Behnken design was applied to the preparation of chitosan to investigate effects of factors such as the HCl solution concentration, protein removal time and deacetylation time on the degree of deacetylation (%DD). Scanning electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy and gel permeation chromatography were employed to examine the chitosan structure, as well as pH titration and antibacterial testing of the chitosan solution. Results revealed that as-p chitosan comprises specific functional groups, with almost no impurities. Its average molecular weight was ∼225,000 g/mol, and %DD was ∼89.7%. The chitosan/PVA composite was prepared and investigated for the adsorption of nitrate and phosphate ions in water. Experimental results revealed that the adsorption capacity of a chitosan/PVA (1:2) composite is better than that of chitosan. Accordingly, the theoretical maximum adsorption capacities of nitrate and phosphate ions on chitosan were 122.0 mg/g and 344.8 mg/g, respectively. The corresponding values on the chitosan/PVA (1:2) composite were 135.1 mg/g and 384.6 mg/g. Adsorption kinetics data at 25 °C were well fitted to the pseudo-second-order model (R2 > 0.998). These results revealed that crab shell chitosan and the chitosan/PVA (1:2) composite can be used for the adsorption of nitrates and phosphates in aqueous solutions. HIGHLIGHTS The process of preparing chitosan from the shell of Somanniathelphusa Sinensis was optimized by Box-Behnken design.; The characterization of chitosan showed that it was successfully prepared with high DD value, moderate molecular weight, good antibacterial properties and no impurities.; Chitosan/PVA composites were prepared with uniform distribution, uniform particle size.; Crab shell chitosan and Chitosan/PVA (1:2) composite show good adsorption capacity of nitrate and phosphate ions in aqueous solution.;

Rourea harmandiana Pierre is a species which belongs to the family of Connaraceae. This plant is found abundantly in central of Vietnam (Thua Thien - Hue, Da Nang). Chemical study on the ethyl acetate extract of Rourea harmandiana leaves has led to the isolation of four compounds including vomifoliol (1), boscialin (2), abscisic acid (3) and p-coumaric acid (4). The structures of these compounds have been identified by NMR, MS spectroscopic data and comparison with the reported literature. These compounds were isolated from Rourea harmandiana species as well as from the genus Rourea for the first time.

In this study, electro-Fenton (EF) was employed for the removal of tricyclazole (TC) and total organic carbon (TOC) in real pesticide wastewater (RPW). The central composite design (CCD) with three parameters, that is, current density, Fe2+ concentration, and electrolysis time, has been conducted to predict the TOC and TC removal efficiency. The high correlation of the quadratic models of 0.9842 and 0.9781 for TC and TOC removal, respectively, indicates the significance of the models. The obtained results revealed that the high-efficiency removal of both TC and TOC in RPW. Approximately 99.6% of TC was decomposed under the optimum conditions of a current density of 2.2 mA/cm2 and an Fe2+ concentration of 0.2 mM during 188 min with an operating cost of 121.392 $/kg TC or ∼2.692 $/m3, while 84.2% TOC was eliminated at a current density of 2.2 mA/cm2 and an Fe2+ concentration of 0.2 mM during 217 min with an operating cost of 3.019 $/kg TOC or 3.916 $/m3. Acute toxicity tests at optimal condition revealed moderate exhibition toxicity of treated wastewater against Daphnia magna with LC50 values of 3.12%, 2.05%, 1.84%, and 1.36% at 24 h, 48 h, 72 h, and 96 h, respectively. The removal of TC and TOC followed pseudo-first-order kinetic with an R2 of ∼0.993 and 0.923, respectively.

Hand, foot and mouth disease (HFMD) is an emerging infection with pandemic potential. Knowledge of neutralizing antibody responses among its pathogens is essential to inform vaccine development and epidemiologic research. We used 120 paired-plasma samples collected at enrollment and >7 days after the onset of illness from HFMD patients infected with enterovirus A71 (EV-A71), coxsackievirus A (CVA) 6, CVA10, and CVA16 to study cross neutralization. For homotypic viruses, seropositivity increased from

As cobalt (Co) has been the most useful element for activating Oxone to generate SO4•−, this study aims to develop a hierarchical catalyst with nanoscale functionality and macroscale convenience by decorating nanoscale Co-based oxides on macroscale supports. Specifically, a facile protocol is proposed by utilizing Cu mesh itself as a Cu source for fabricating CuCo2O4 on Cu mesh. By changing the dosages of the Co precursor and carbamide, various nanostructures of CuCo2O4 grown on a Cu mesh can be afforded, including nanoscale needles, flowers, and sheets. Even though the Cu mesh itself can be also transformed to a Cu-Oxide mesh, the growth of CuCo2O4 on the Cu mesh significantly improves its physical, chemical, and electrochemical properties, making these CuCo2O4@Cu meshes much more superior catalysts for activating Oxone to degrade the Azo toxicant, Acid Red 27. More interestingly, the flower-like CuCo2O4@Cu mesh exhibits a higher specific surface area and more superior electrochemical performance, enabling the flower-like CuCo2O4@Cu mesh to show the highest catalytic activity for Oxone activation to degrade Acid Red 27. The flower-like CuCo2O4@Cu mesh also exhibits a much lower Ea of Acid Red 27 degradation than the reported catalysts. These results demonstrate that CuCo2O4@Cu meshes are advantageous heterogeneous catalysts for Oxone activation, and especially, the flower-like CuCo2O4@Cu mesh appears as the most effective CuCo2O4@Cu mesh to eliminate the toxic Acid Red 27.

Bis(4-hydroxyphenyl)methanone (BHPM), a common ultraviolet stabilizer and filter (USF), is extensively added in sunscreens; however, BHPM is proven as an endocrine disruptor, posing a serious threat to aquatic ecology, and BHPM should be then removed. As sulfate radical (SO4•−) could be useful for eliminating emerging contaminants, oxone appears as a favorable source reagent of SO4•− for degrading BHPM. Even though cobalt is a useful catalyst for activating oxone to generate SO4•−, it would be even more promising to utilize ambient-visible-light irradiation to enhance oxone activation using cobaltic catalysts. Therefore, in contrast to the conventional cobalt oxide, cobalt titanium oxide (CTO) was investigated for chemical and photocatalytic activation of oxone to eliminate BHPM from water. Especially, a special morphology of nanosheet-assembled configuration of CTO was designed to maximize active surfaces and sites of CTO. Thus, CTO outperforms Co3O4 and TiO2 in degrading BHPM via oxone activation. Furthermore, the substituent of Ti enabled CTO to enhance absorption of visible light and possessed a much smaller Eg. These photocatalytic properties intensified CTO’s activity for oxone activation. CTO possessed a significantly smaller Ea of degradation of USFs than other catalytic systems. Mechanistic insight for degrading BHPM by CTO + oxone was explicated for identifying contribution of reactive oxygen species to BHPM degradation. The BHPM degradation pathway was also investigated and unveiled in details via the DFT calculation. These results validated that CTO is a superior cobaltic alternative for activating oxone to eliminate BHPM.

Background: Hand, Foot and Mouth Disease (HFMD) is a major public health concern in the Asia-Pacific region. Most recent HFMD outbreaks have been caused by enterovirus A71 (EV-A71), coxsackievirus A16 (CVA16), CVA10, and CVA6. There has been no report regarding the epidemiology and genetic diversity of CVA16 in Vietnam. Such knowledge is critical to inform the development of intervention strategies.Materials and Methods: From 2011 to 2017, clinical samples were collected from in- and outpatients enrolled in a HFMD research program conducted at three referral hospitals in Ho Chi Minh City (HCMC), Vietnam. Throat or rectal swabs positive for CVA16 with sufficient viral load were selected for whole genome sequencing and evolutionary analysis.Results: Throughout the study period, 320 CVA16 positive samples were collected from 2808 HFMD patients (11.4%). 59.4% of patients were male. The median age was 20.8 months (IQR, 14.96–31.41). Patients resided in HCMC (55.3%), Mekong Delta (22.2%), and South East Vietnam (22.5%). 10% of CVA16 infected patients had moderately severe or severe HFMD. CVA16 positive samples from 153 patients were selected for whole genome sequencing, and 66 complete genomes were obtained. Phylogenetic analysis demonstrated that Vietnamese CVA16 strains belong to a single genogroup B1a that clusters together with isolates from China, Japan, Thailand, Malaysia, France and Australia. The CVA16 strains of the present study were circulating in Vietnam some 4 years prior to its detection in HFMD cases.Conclusion: We report for the first time on the molecular epidemiology of CVA16 in Vietnam. Unlike EV-A71, which showed frequent replacement between subgenogroups B5 and C4 every 2–3 years in Vietnam, CVA16 displays a less pronounced genetic alternation with only subgenogroup B1a circulating in Vietnam since 2011. Our collective findings emphasize the importance of active surveillance for viral circulation in HFMD endemic countries, critical to informing outbreak response and vaccine development.

Soil salinity expressed by electrical conductivity is a threat to crop production. The study aims were to establish relationships of electrical conductivity with its relevant soil properties, and analyze variability of soil salinity in the coastal zone of Bangladesh. A total of 150 geo-referenced saline soil samples from three coastal districts (Khulna, Satkhira and Bhola) of Bangladesh were analyzed for electrical conductivity of saturated paste extract (ECe), salt cations and other soil properties related to salinity. Statistical and geostatistical analyses were done as required. Moderate to strong significant regression relationships (R2=0.42 to 0.94) were found between ECe and salt cations (ECe=43.12*Na2-46.36*Na+13.97; ECe=12.26*K-2.5;ECe=1.16*Ca-1.97; ECe=0.32*Mg2-1.60*Mg+3.53) of the soils. On the contrary, weak relationships (R2=0.05 to 0.21) were found between ECe and other soil properties (ECe=4.41*organic carbon-0.56; ECe=-1.71*Txw (soil texture)+3.98;ECe=0.35*cation exchange capacity-1.98; ECe=0.06*specific surface area-0.55). Khulna soils (CV=65.99%) showed lower statistical variations while Satkhira (CV=97%) and Bhola (CV=105%) soils showed higher statistical variations for ECe. In contrast, Khulna, Satkhira and Bhola soils showed strong, moderate and weak spatial dependency for ECe, respectively. Interpolated spatial distribution maps of ECe showed variations in individual districts of study areas. The findings would assist soil scientists or farm managers to understand and/or manage saline soils, specially the soils of coastal zone of Bangladesh.

We investigated enterovirus A71–associated hand, foot and mouth disease in Vietnam and found that, after replacing subgenogroup C4 in 2013, B5 remained the leading cause of this disease. In contrast with previous observations, this switch did not result in an explosive outbreak, and B5 evolution was driven by negative selection.