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The co-precipitation technique was used to produce Zn1-x-yYbxAgyO nanomaterials. The Zn1-x-yYbxAgyO nanomaterials have higher photocatalytic activity compared to ZnO, owing to their exceptional optical and electrical characteristics. The results demonstrate that the Zn0.096Yb0.02Ag0.02O nanoparticles are capable of decomposing 98.2 % of RhB dye after 15 min by photodegradation. Moreover, studies have shown that superoxide radicals actively participate in the process of photodegradation.

The objective of this study is to determine the fibrin monomer reference intervals in healthy children. This cross-sectional study was conducted in the Hematology Department at Vietnam National Children's Hospital (April 2023 to March 2024). Children without prior history of clotting disorders or anticoagulants use hospitalized in preparation for orthopedic surgery or inguinal hernia surgery were enrolled in the study. The fibrin monomer test method was the quantitative fibrin monomer test on the STA-R system (Diagnostica Stago™, France). Eighty-six children (58 males and 28 females) were enrolled in the study. The median (interquartile range, 2.5th-97.5th) fibrin monomer value of the study subjects was 2.56 (0.11-5.93) µg/mL, with no statistically significant difference in fibrin monomer values among the age groups of 1 month to 3 years, 3 years to 13 years, and 13 years to 18 years. This is the first study conducted in Vietnam to determine reference values of fibrin monomer in children. This information can help in the diagnosis and treatment of early hypercoagulation stage and disseminated intravascular coagulation in children.

Colistin-resistant Escherichia coli (COE) has been recently recognized as a serious threat to animal and human health. This study aimed to determine the prevalence and antibiotic resistance profile of COE isolated from raw beef and cow feces in Vietnam. Our results showed that 16% (16/100) and 32% (32/100) of raw beef and cow feces samples were positive for COE, respectively. A total of 48 COE strains were isolated, with 16 originating from raw beef and 32 from cow feces samples. The antibiotic susceptibility test revealed that the COE isolates were highly resistant to ampicillin, tetracycline, florfenicol, trimethoprim/sulfamethoxazole, streptomycin, and nalidixic acid, with resistance rates ranging from 66.67% to 87.5%. In addition, 87.5% of the isolates were identified to be multidrug-resistant strains. Further molecular characterization indicated that all COE isolates carried the mcr-1 gene, with 16 of them also harboring blaCTX-M-55 genes. Taken together, the findings in this study demonstrate that raw beef and cow feces are important sources of COE, which can be potentially transmitted to humans through the food chain.

Shiga toxin-producing Escherichia coli (STEC) is one of the most important foodborne pathogens, and the rise of antibiotic resistance to it is a significant threat to global public health. The purpose of this study is to investigate the prevalence, molecular characterization, and antibiotic resistance of STEC isolated from raw meat in Vietnam. The findings in this study showed that the prevalence of STEC in raw beef, pork, and chicken meat was 9.72% (7/72), 5.56% (4/72), and 1.39% (1/72), respectively. The STEC isolates were highly resistant to ampicillin (91.67%) and tetracycline (91.67%), followed by trimethoprim/sulfamethoxazole (83.33%), streptomycin (75%), and florfenicol (66.67%). The incidence of STEC virulence-associated genes, including stx1, stx2, eae, and ehxA, was 8.33% (1/12), 91.67% (11/12), 33.33% (4/12), and 58.33% (7/12), respectively. STEC serogroups O157, O26, and O111 were detected in 3 out of 12 STEC isolates. Two isolates were found to be ESBL producers carrying the blaCTX-M-55 gene, and three isolates were colistin-resistant strains harboring the mcr-1 gene. Notably, a STEC O111 isolate from chicken meat harbored both the blaCTX-M-55 and mcr-1 genes.

E. coli is an important zoonotic pathogen capable of causing foodborne illness and bovine mastitis. Bacteriophages have been increasingly considered a promising tool to control unwanted bacteria. The aim of this study is to determine the antibiotic resistance profile of E. coli isolated from raw milk and the efficacy of phage in controlling multidrug-resistant E. coli in raw milk. Antibiotic susceptibility testing showed the highest resistance rates of E. coli isolates to co-trime (27.34%) and ampicillin (27.34%), followed by streptomycin (25.18%), tetracycline (23.02%), and the lowest resistance rates to ciprofloxacin, gentamycin, and ceftazidime, all at a rate of 2.16%. All isolates were susceptible to meropenem. Of the 139 E. coli isolates, 57 (41.01%) were resistant to at least one antibiotic, and 35 (25.18%) were classified as MDR strains. Molecular characterization indicated that 5 (3.6%) out of the 139 isolates were STEC strains carrying stx1 gene. Seven (5.04%) isolates were phenotypically identified as ESBLEC, and four isolates (2.88%) were resistant to colistin. The results of the genotypic test revealed that four out of seven ESBLEC strains carried both blaTEM and blaCTX-M-1, two harbored blaTEM, and one possessed blaCTX-M-1, while mcr-1 was detected in all four colistin-resistant E. coli isolates. In particular, one isolated E. coli strain (EM148) was determined to be a multidrug-resistant strain simultaneously carrying blaTEM, blaCTX-M-1, and mcr-1. A total of eight phages were successfully recovered from raw milk. The application of phage PEM3 significantly reduced viable counts of multidrug-resistant host EM148 in raw milk by at least 2.31 log CFU/mL at both 24 °C and 4 °C.

Clostridium perfringens is one of the most important zoonotic pathogens as it can cause food poisoning in humans and necrotic enteritis in both animals and humans. Meat, especially pork and chicken meat, is considered the main vehicle for the transmission of C. perfringens from animals to humans. The purpose of this study was to determine the prevalence, toxinotype, and antimicrobial resistance profile of C. perfringens isolated from pork and chicken meat sold in Vietnam. The isolation results showed that 15/50 (30%) of pork samples and 8/50 (16%) of chicken meat samples were contaminated with C. perfringens. The isolates exhibited their highest resistance rate to tetracycline (21/23; 91.30%) and clindamycin (10/23; 43.48%). On the contrary, their lowest resistance rates were observed in response to imipenem (2/23; 8.70%) and cefoxitin (1/23; 4.35%). In particular, 34.78% (8/23) of C. perfringens isolates were identified to be multidrug-resistant strains. The results of toxin genotyping indicated that all isolates were positive for the cpa gene and belonged to type A.

Recently, neural video compression networks have obtained impressive results. However, previous neural video compression models mostly focus on low-delay configuration with the order of display being the same as the order of coding. In this paper, we propose a hierarchical random access coding approach that exploits bidirectionally temporal redundancy to improve the coding efficiency of existing deep neural video compression models. The proposed framework applies a video frame interpolation network to improve inter-frame prediction. In addition, a hierarchical coding structure is also proposed in this paper. Experimental results show the proposed framework improves the coding efficiency of the base deep neural model by 48.01% with the UVG dataset, 50.96% with the HEVC-class B dataset, and outperforms the previous deep neural video compression networks.

For decades, abundant studies have illustrated the vast scholarly publication disparity between male and women academics. Exhaustingly, in 21st-century higher education, women’s academic research participation is below the world average, except in a few countries that comprehensively studied their faculties and personal and institutional agencies to restore parity. Higher education is widely discussed in Vietnam as incompetent academics with a shred of scholarly publications and venerable gender disparities. Hence, the current study sought to contribute robust policy and practical implications for stakeholders by inspecting women’s faculties solely to shed light on the root hindrances of their scholarly share. Remarkably, the findings of the study demonstrate that women faculty members have promising scholarly contributions in disciplines where women scientists are marginalized, that having children becomes a notable motivator for mothers in academia, and that there is genuine support from a husband who understands the worth of his wife’s research contribution to the institution and family.

Previous studies on responses of Foreign Direct Investment (FDI) firms to policy changes mainly focus on the impact of government policies on foreign investment flows in a country or in a province. So far, there has been no research on how Foreign Direct Investment enterprises, which are investing in Vietnam, react to unexpected changes in policies. We focus on studying some main factors affecting the behavior of FDI firms in Vietnam when the policy changes adversely. Using the data set of the annual Vietnam Provincial Competitiveness Index (PCI) survey with the foreign invested firms (FIFs) in Vietnam for 4 years from 2013 to 2016, the study shows that enterprises’ behaviors strongly depend on the capacity to predict changes in government policies. The policy changes directly affect business activities, so policymakers need to make a long-term stability plan to attract the FIFs. In addition, the FIFs tend to choose moving production to another country or coordinating with other businesses if local leaders are highly transparent. The opposite is true for the proactivity. In the case that local leaders are proactive, it helps FIFs feel secure to invest with enthusiastic support so the desire to move location or coordinate with other businesses is reduced. On the other hand, the FIFs are more likely to employ both formal and informal diplomacy if there is an increase in the number of employees, time spent interacting with government officers and prediction about policy change. Moreover, it is more likely to employ formal diplomacy than informal diplomacy in the case of FIFs’ size expanding. Similar to that case, it is true when increasing the capability of predicting harmful policy changes. We also find that the tendency of choosing formal diplomacy of foreign leaders is higher than that of Vietnamese leaders.

This paper explores the maximum amount of rainfall in the Central coastal provinces of Vietnam (Quang Binh case study) for return periods of 5 years, 10 years, 20 years, 50 years, and 100 years, which correspond to frequencies of 20%, 10%, 5%, 2%, and 1%, respectively. The results show that at a frequency of 20%, the maximum intensity of rain during a heavy rain spell can range from 636.6 to 696.0 mm, while the maximum one-day amount received was over 300 mm, which can occur many times in 5 years. At a frequency of 1%, the intensity of rain during a heavy rain spell can range from 1,197.9 to 1,268.3 mm, while the maximum one-day amount ranged from 487.4 to 521.9 mm. However, such values are very rare over the course of 100 years. In addition, in terms of annual rainfall, the spatial distribution of heavy rainfall in coastal areas was significantly smaller than that in mountainous areas. The highest one-day and five-day rainfall have the same pattern of spatial distribution as annual rainfall.

This research investigates the perspectives of the novice lecturers in the Faculty of English Language Teacher Education (FELTE) regarding Teaching Practicum’s impacts on their classroom management skills. Using survey research, data was gathered through questionnaires distributed among the whole population of 29 participants, followed by semi-structured interviews to gain a deeper insight into participants’ experience. The study’s results showed that novice lecturers generally made considerable progress in classroom management skills, especially in attention-drawing and response encouragement, creation of a motivating environment as well as physical and emotional interactions with students. On the other hand, it was discovered that inadequate duration and inappropriate timing generally impeded novice lecturers’ gains during their Teaching Practicum. However, some challenges related to supervisor and school choice turned out to be significant factors from which participants could derive considerable benefits, which is opposed to previous research. At the end of the study, some recommendations were suggested for future research on this topic.

Optical flows and video frame interpolation are considered as a chicken-egg problem such that one problem affects the other and vice versa. This paper presents a stack of deep networks to estimate intermediate optical flows from the very first intermediate synthesized frame and later generate the very end interpolated frame by combining the very first one and two learned intermediate optical flows based warped frames. The primary benefit is that it glues two problems into a single comprehensive framework that learns altogether by using both an analysis-by-synthesis technique for optical flow estimation and Convolutional Neural Networks (CNN) kernels-based frame synthesis. The proposed network is the first attempt to merge two previous branches of previous approaches, optical flow-based synthesis and CNN kernels-based synthesis into a comprehensive network. Experiments are carried out with various challenging datasets, all showing that the proposed network outperforms the state-of-the-art methods with significant margins for video frame interpolation and the estimated optical flows are more accurate for challenging movements. Furthermore, the proposed Motion Estimation Motion Compensation (MEMC) network shows its outstanding enhancement of the quality of compressed videos.

This paper presents a multi-criteria assessment approach for the prioritisation of low-carbon technologies for the waste sector in order to enable the implementation of Vietnam’s nationally determined contributions (NDCs) in terms of the Paris Agreement. A four-step approach is developed for assessing and prioritising low-carbon technologies for the waste sector using this approach. A set of five criteria and indicators are defined for multi-criteria assessment. Based on mitigation options defined in the NDCs, a shortlist of 26 technological options are defined. The multi-criteria assessment and prioritisation is conducted based on the shortlist. The assessment results in eight prioritised low-carbon technologies. Of the eight technologies prioritised, semi-aerobic landfill, which is a low cost and relatively simpler technology than the other technologies evaluated and can contribute to greenhouse gas emission reduction, is given the highest priority. The technical, financial, and social and environmental feasibility of each of the technologies evaluated is presented.

Block-based hierarchical motion estimations are widely used for frame interpolation in frame-rate up-conversion and are successful in generating high-quality interpolations. However, it still fails in the motion estimation of small objects when a background region moves in a different direction. This is because the motion of small objects is neglected by the down-sampling and over-smoothing operations at the top level of image pyramids in the maximum a posterior (MAP) method. Consequently, the motion vector of small objects cannot be detected at the bottom level, and therefore, the small objects often appear deformed in an interpolated frame. This paper proposes a novel algorithm that preserves the motion vector of the small objects by adding a secondary motion vector candidate that represents the movement of the small objects. This additional candidate always propagates from the top to the bottom layers of the image pyramid. Experimental results demonstrate that the intermediate frame interpolated by the proposed algorithm significantly improves the visual quality when compared with conventional MAP-based frame interpolation.

Nanostructures of titanium nitride (TiN) have recently been considered as a new class of plasmonic materials that have been utilized in many solar energy applications. This work presents the synthesis of a novel nanostructure of TiN that has a nanodonut shape from natural ilmenite ore using a low-cost and bulk method. The TiN nanodonuts exhibit strong and spectrally broad localized surface plasmon resonance absorption in the visible region centered at 560 nm, which is well suited for thermoplasmonic applications as a nanoscale heat source. The heat generation is investigated by water evaporation experiments under simulated solar light, demonstrating excellent solar light harvesting performance of the nanodonut structure.

Human activities, such as plant cultivation, enhance the activity concentrations (ACs) of radionuclides in the topsoil and have the potential to affect humans and the environment. The soil with a high radiation background not only acts as a source of continuous radiation exposure to humans but also as a medium of migration for the transfer of radionuclides to food crops. Some spectrometers can measure the AC of radionuclides in the soil, but long‐term variation of AC is difficult to investigate. Therefore, developing methods for predicting the AC of radionuclides in agricultural soil is an interesting topic that many studies have focused on. In this work, a simple method was introduced to estimate long‐term changes of some radioisotopes in the top layer of soil (0–20 cm). The estimation considered four major processes: fertilization, irrigation, vertical leaching, and plant uptake. The leaching rates (Rl) of radionuclides were predicted by their ACs in the soil water and the infiltration rate of water in the soil. The method was applied to the soils of five study fields in southern Vietnam, and the Rl values of 226Ra were between 7.4 Bq·m−2·y−1 and 60 Bq·m−2·y−1, while the rates of 210Po were between 22.1 and 111 Bq·m−2·y−1. For long‐term assessment, it was found that 226Ra increases in sweat potato soil and tomato soil with annual rates (ΔC) of 0.99 Bq·kg−1·y−1 and 0.69 Bq·kg−1·y−1, respectively. The AC of 210Po was predicted to increase in some soils. The corresponding ΔC values for 210Po were 0.028 Bq·kg−1·y−1 in rice, 0.617 Bq·kg−1·y−1 sweet potato, and 0.099 Bq·kg−1·y−1 in tomato soils. The results imply that interventions are necessary to reduce the radioactivity accumulation in fields with high ΔC values. The effective methods can be changing the fertilizer types and the irrigation systems. [ABSTRACT FROM AUTHOR]

The abandonment of stone quarries establishes a quarry lake ecosystem that includes soil, water, fish, and vegetarian cover. The activity concentrations (ACs) of natural radionuclides in the waters of several quarry lakes worldwide have not been investigated. In addition, the features of radionuclides, such as distribution, seasonal variability, and health risks, have not been studied. In this study, the ACs of 226Ra, 234U, and 238U were measured in a typical quarry lake in Vietnam with an area of approximately 4000 m2. The average ACs of 226Ra, 234U, and 238U were 8.3, 13.8, and 17.7 mBq L−1, respectively. The ratios of 226Ra/234U, 226Ra/238U, and 234U/238U were 0.47, 0.6, and 0.79, respectively. A linear correlation was found between ACs and water depth. The ACs predicted by the QWASI (Quantitative Water, Air, Sediment Interaction) model agree with the measured values. [ABSTRACT FROM AUTHOR]