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The study investigates the application of G. Polya’s four-step problem-solving process in teaching Physics. This teaching method helps students form and develop problem-solving skills in learning, including (1) Understanding the problem; (2) Making a plan; (3) Executing the plan; (4) Looking back and reflecting. An experimental teaching session on “some forces in practice” for 300 tenth graders in two high schools (grade 10) was conducted as part of this study. Experimental results at first show that more than 80% of students have significantly improved their problem-solving skills. These experimental results are expected to enable teachers and students to teach and learn Physics effectively, meeting the expected outcomes of the General Education Program.

Background: The limb-lead criterion is a simple new standard with high diagnostic value to distinguish the cause of wide QRS tachycardia, easy to apply in emergency conditions. Methods: A cross-sectional descriptive study of 61 patients with electrocardiogram of wide QRS tachycardia at Cardiovascular Center- Hospital E and Vietnam Heart Institute- Bach Mai Hospital from January 2017 to October -2022. Evaluating the value of limb – leads Criterionand comparing to several other criteria. Results: In 61 patients, 43 patients with VT, 18 patients with SVT, 54.1% male, history of ischemic heart disease (3.3%), heart failure (11.5%), no history structural cardiovascular disease (83.6%). Mean heart rate was 182, 80 ± 20.58 bpm, average QRS width was 137.89 ± 12.59mms. Sensitivity, specificity, positive predictive value, negative predictive value of Brugada criterionwere 97.7%, 88.9%, 95.5%, 94.1%, respectively; of Pava criterionwere 53.5%, 88.9%, 92%, 44.4%; of Vereckei criterionwere 60.5%, 100%, 100%, 51.4%; of limb-leads criterion is 86.1%, 83.3%, 92.5%, 71.4%; when combining Limb lead and Pava criteriawere 90.9%, 82.4%, 93%, 77.8%. Conclusion: The limb-lead criterion is an easy-to-usealgorithm, only using morphology to distinguish wide QRS tachycardias, has high diagnostic value, so it should widely applied in cardiovascular emergency.

This article aims at reducing the cost of energy by targeting the optimal power of the wind generator of offshore wind farms in a region in Vietnam. The research employs various scaling laws for mass and cost calculations. The calculations are implemented using wind data of a specific region on the South-Central Coast. The permanent magnet synchronous generator with high efficiency, light-weight, and compact design will be used for the wind generator. The levelized cost of energy as a function of the generator’s nominal power is then built to figure out the optimal power of the wind generator. Results show that future offshore wind farms with monopile foundations having a mean wind speed of about 6.5 m/s should be installed with a turbine's nominal power of 7 MW.

This article investigates the structural optimization of a 20-MW offshore wind generator to minimize the torque ripple and mass. The surface-mounted permanent magnet topology will be chosen for the generator. In addition, the double-layer armature winding configuration will be utilized. The direct-drive technology will be adopted to increase the reliability of the offshore wind energy conversion system. The multi-objective optimization of the generator is carried out based on the particle swarm algorithm. Results show that the torque ripple of the optimal model is significantly reduced to as much as 0.41% at full-load conditions making the configuration suitable for the high-power offshore wind generator.

This study uses the Vietnam Living Standards Households Survey 2018 to document the relationship between birthplace diversity and child welfare in Vietnam. To address the endogeneity issue of birthplace diversity, we construct an instrumental variable. The endogeneity-corrected estimates show that a 1 percent increase in birthplace diversity significantly increases education expenditure per capita for children aged 2 to 18 by 0.9 percent and health expenditure for children aged 6 to 11 by 0.5 percent. We document an income channel through which birthplace diversity affects child welfare. Our instrumental variable estimation provides consistent results when we use an alternative instrumental variable. Our findings suggest that promoting migration is likely to be an effective way of enhancing the welfare of children and increasing economic prosperity.

Zinc oxide (ZnO) is one of the most promising oxide possibilities for use in a number of industries due to its unique properties. Because of its broad direct bandgap (3.37 eV) and strong exciton binding energy (60 meV) at ambient temperature, ZnO not only conducts electricity well but also transmits visible light and emits UV light. Here, we investigated the effect of growth temperature on ZnO thin films by changing the growth temperatures from 400 oC to 450 oC. Radio-frequency (RF) magnetron sputtering was used to create ZnO thin films on Si(100) substrates. The atomic force microscopy (AFM) results show that the root-mean-square (RMS) roughness decreases from 6.1 ± 1.0 nm to 4.8 ± 0.6 nm as the growth temperatures increase. XRD patterns display the enhancement of ZnO’s structure when increasing the growth temperature. Our findings indicate that controlling growth temperature is the critical factor in producing high quality ZnO thin films.

Magnetite (Fe3O4) is a potential material for spintronic development due to its high Curie temperature (858 K) and half-metallic structure with only one spin polarization at Fermi level. The bulk properties of Fe3O4 make it a big challenge to grow perfectly stoichiometric thin films at a low temperature. Here, we report the structural and morphological evolution of the Fe3O4 thin films as a function of gas flow rate. Radio-frequency (RF) magnetron sputtering was used to fabricate Fe3O4 thin films on the MgO/Ta/SiO2 structure at room temperature. Atomic force microscopy (AFM) shows a spherical-like shape, the root-mean-square (RMS) roughness varies from 1.5 nm to 7.5 nm, and grain size increases from 30 nm to 74.3 nm. The structural properties of Fe3O4 films are dramatically enhanced by increasing the gas flow rate. Moreover, the resistivity (r) versus temperature (T) reveals the existence of a Verwey transition below 120 K, indicating the presence of Fe3O4.

Myotis alticraniatus is a small mammal species with widespread distribution in Vietnam and other Asian countries. However, prior to the present study, its echolocation calls were poorly documented. Between 2018 and 2020, we conducted bat surveys in Cat Ba National Park and other areas of Vietnam. Echolocation calls of the species were obtained in different recording situations: handheld, flying inside a fight tent and foraging in natural habitats. The average initial frequency (iFM) and terminal frequency (tFM) of this species’ echolocation calls are in ranges of 113.2-140 kHz and 57.8-68.6 kHz, respectively. Its call duration is in a range of 1.6-3.9 ms. When detecting an object or prey in natural habitats, the species emitted echolocation calls in groups of up to 10 signals with the iFM and tFM values in ranges of 60.6-64.3 kHz and 28.2-31.0 kHz, respectively. Results from the present study exhibited a wide variation in frequencies and signal shapes of the species echolocation calls.

In this work, the algorithm and computer code, named DETO, used to calculate the detonation wave parameters (i.e., the velocity of detonation and the detonation pressure) of aluminized explosives, based on the chemical equilibrium theory of detonation products, the hydrodynamic theory of detonation process, and the Becker - Kistiakowsky - Wilson (BKW) equation of state. The aluminum (Al) content reacting with detonation products on the detonation wavefront can be changed according to the user's assumptions. Compared to experimental data for several aluminized explosive types, the results calculated by DETO have the same, even higher accuracy than those calculated by other computer codes previously published. Specifically, the mean absolute deviation from experimental data is about 2% for the velocity of detonation (VOD) and about 8% for the pressure on the detonation wavefront. In addition, the study also confirmed that about 50% of Al powders participate in the reaction on the detonation wavefront.

In this study, the optimization of the cationic polymerization of vinyl ether monomers was carried out. The aim is to maximize the conversion of the monomers. A factorial design was used to evaluate the effects and interactions of three factors: photoinitiator concentration, the weight ratio of monomer and oligomer and alcohol concentration on the conversion of monomers. The optimal conditions from the desirable response are initiator concentration 5%, monomer/oligomer 1/1, and alcohol concentration 1.45%. Under these conditions, the conversion of 86.5% is obtained. The polymerization prepared under the optimized conditions verified the statistical experimental strategies' validity

In this work, the preparation of 2,4,6-trinitroresorcinol by the sulfonation-nitration method of resorcinol through three stages was investigated. The results showed that the 2,4,6-trinitroresorcinol synthesis efficiency reached the highest value (82-83%) when the molar ratio of HNO3/resorcinol was 3.45/1, the temperature of the nitrate stage was 30-70 ºC, and the concentration of HNO3 solution was 72%. Besides, the results of 2,4,6-trinitroresorcinol thermal analysis by TGA/DTA methods demonstrated that there are one melting point and two thermal decomposition points in the temperature range from 50 to 400 ºC.

Multi-document summarization is challenging because the summaries should not only describe the most important information from all documents but also provide a coherent interpretation of the documents. This paper proposes a method for multi-document summarization based on cluster similarity. In the extractive method we use hybrid model based on a modified version of the PageRank algorithm and a text correlation considerations mechanism. After generating summaries by selecting the most important sentences from each cluster, we apply BARTpho and ViT5 to construct the abstractive models. Both extractive and abstractive approaches were considered in this study. The proposed method achieves competitive results in VLSP 2022 competition., In Proceedings of the 9th International Workshop on Vietnamese Language and Speech Processing (VLSP 2022)

Temporomandibular joint dysfunction (TMD) is a common disease, especially increasing in young people, and affects the quality of life. Clinical signs of TMDs are various and complex. Diagnosis of symptoms and prognosis is essential. Therefore, we conducted a cross-sectional descriptive study on 61 patients aged 19-23 who participated voluntarily from February to June 2022 at the Odonto-Stomatology clinic at the University of Medicine and Pharmacy, Vietnam National University. The results showed that the proportion of women with symptoms was higher than that of men. For the clinical symptoms, percentages of the limited range of mandibular movements and mouth gap deviation were quite high (77.0% and 68.9%, respectively). Joint sounds and arthralgia took 31.1% and 24.6%, while myalgia accounted for only 11.5%. In the joint, the pain was detected mainly on the outer surface of the joint (24.6%). In both genders, the masseter muscle was the most painful muscle group. Clinical symptoms are very important in diagnosis, treatment, and prognosis. Keywords: Clinical signs, temporomandibular joint dysfunction, students.

Overview Covid-19 is an emerging infectious disease, and a current pandemic with the death rate about 2.3%. It causes cardiovascular complications. Myocardial injury (MI) is the most common one. Method 50 inpatients at Sa Dec General Hospital from 1st Aug to 10th Sep, 2021 were recruited, and divided into 2 groups (with and without MI, which based on levels of Troponin Ths on admission). Results Patient characteristics, clinical manifestations, and lab tests were assessed and compared between two groups. Comparison to the group without MI, the group with MI has higher age (68.33 ± 14.67 vs 55.65 ± 15.09, p = 0.004), more underlying cardiovascular diseases (34.1% vs 11.1%, p = 0.02), and coronary artery disease (19.6% vs 2.8%, p = 0.03). MI increases 28-day mortality rate in the intensive care unit (p = 0.002). The age of more than 60 also contributes to increase the mortality rate. Conclusion Myocardial injury is a common complication in severe Covid-19 patients, which increases the mortality rate in this group.

This study investigates the impact of natural disasters on womenʼs empowerment in rural Vietnam. Using Vietnam Access to Resources Household Surveys 2008 and 2010, we find strong evidence on the impact of natural disasters on womenʼs empowerment. Non-parametric methods also corroborate this finding. Our estimates are strong for different model specifications and different measures of womenʼs empowerment. We also discuss channels through which natural disasters affect womenʼs empowerment. In an agrarian society, men have an advantage in agricultural activities relative to women, therefore women have less power within households compared with men. Our empirical results show that higher number of natural disasters results in a reduction in agricultural income. This decreases menʼs power relative to womenʼs power within households. The impact of number of natural disasters on womenʼs empowerment is statistically insignificant for households with lower shares of farm income while it is statistically significant for households with higher shares of farm income. Leveraging a test of exogeneity by Caetano (2015), we document the causal relationship between natural disasters and womenʼs empowerment.

Sucrose controls various developmental and metabolic processes in plants. It also functions as a signaling molecule in the synthesis of carbohydrates, storage proteins, and anthocyanins, as well as in floral induction and defense response. We found that sucrose preferentially induced OsWRKY7, whereas other sugars (such as mannitol, glucose, fructose, galactose, and maltose) did not have the same effect. A hexokinase inhibitor mannoheptulose did not block the effect of sucrose, which is consequently thought to function directly. MG132 inhibited sucrose induction, suggesting that a repressor upstream of OsWRKY7 is degraded by the 26S proteasome pathway. The 3-kb promoter sequence of OsWRKY7 was preferentially induced by sucrose in the luciferase system. Knockout mutants of OsWRKY7 were more sensitive to the rice blast fungus Magnaporthe oryzae, whereas the overexpression of OsWRKY7 enhanced the resistance, indicating that this gene is a positive regulator in the plant defense against this pathogen. The luciferase activity driven by the OsPR10a promoter was induced by OsWRKY7 and this transcription factor bound to the promoter region of OsPR10a, suggesting that OsWRKY7 directly controls the expression of OsPR10a. We conclude that sucrose promotes the transcript level of OsWRKY7, thereby increasing the expression of OsPR10a for the defense response in rice.

This paper presents the NOWJ team's approach to the COLIEE 2023 Competition, which focuses on advancing legal information processing techniques and applying them to real-world legal scenarios. Our team tackles the four tasks in the competition, which involve legal case retrieval, legal case entailment, statute law retrieval, and legal textual entailment. We employ state-of-the-art machine learning models and innovative approaches, such as BERT, Longformer, BM25-ranking algorithm, and multi-task learning models. Although our team did not achieve state-of-the-art results, our findings provide valuable insights and pave the way for future improvements in legal information processing., Comment: COLIEE 2023

Rodent coat color genes have been studied as a bioresource to understand developmental and cellular processes. The Downunder rat is a fancy variety with a marking on its belly that runs from the neck to the breech and appears to mirror the dorsal hooded marking. Here, we established a congenic strain carrying the Downunder (Du) gene in an F344 genetic background. In addition to the ventral marking, Du/+ rats exhibit anophthalmia or microphthalmia with incomplete penetrance. Du/Du embryos die in the early stages of organogenesis. Genetic linkage analysis mapped the Du gene to rat chromosome 3 and haplotype mapping with congenic rats localized the Du locus to a 3.9-Mb region. The Du locus includes two functional genes, glycosyltransferase-like domain-containing 1 (Gtdc1) and zinc finger E-box binding homeobox 2 (Zeb2). Although we found no functional variation within any of Zeb2's exons or intron-exon boundaries, Zeb2 mRNA levels were significantly lower in Du/+ rats compared with wild-type rats. It is known that melanocyte-specific Zeb2 deletion results in the congenital loss of hair pigmentation in mice. Taken together, our results indicate that the Du mutation exerts pleiotropic effects on hair pigmentation, eye morphology, and development. Moreover, the Zeb2 gene is a strong candidate for the Du mutation.

International audience; With the increasingly rapid penetration of power electronics into AC grid, there is an urgent need in enhancing stability and performance of grid-connected converters. An advanced $H_{\infty}$ multi-input multi-output (MIMO) control using linear matrix inequality (LMI) techniques is introduced and applied for electromagnetic transient (EMT) three-phase voltage source converter (VSC) grid-connected system (simple STATCOM). The proposed control is compared with classical cascade vector control through a validation test of short-circuit event.The comparison results prove that the advanced control approach provides much better performance and transient behaviour compared to classic vector controls, as a result of using $H_{\infty}$ optimization technique to minimize the effect of frequency's and grid voltage's variations. The validation test is done using MATLAB Simscape in EMT simulation, and also gives a step-by-step path of implementation for applying advanced control in industrial-level application of power converter.These results will be further used to control the units of the new concept of \textit{Dynamic Virtual Power Plant} introduced in the H2020 POSYTYF project.

Objective: Cox Maze procedure is an effective surgical treatment of atrial fibrillation and it is often performed concomitantly with mitral valve surgery. However, some patients still experience atrial tachyarrhythmia post-surgery, which adversely affects heart function as well as their quality of life. Method: We present the case of a 66-year-old female patient who underwent mitral valve replacement with a bio-prosthesis and Cox-Maze procedure; she was later admitted to our center after 14 months due to pneumonia and atrial tachycardia. An electrophysiology study/ intervention was performed. Result: We successfully determined the mechanism and ablated the atrial tachyarrhythmia. The sinus rhythm was restored and was maintained 3 months post-procedure, with amelioration of the left ventricular function. Conclusion: Electrophysiology study with electro-anatomy mapping can help to determine the mechanism of arrhythmia to guide successful ablation of post-operative arrhythmia

Skin cancer has emerged as one of the leading types of cancers in the world, causing a high impact on the global burden of health and the economy. Basal cell and squamous cell carcinoma are the localized forms of skin cancer with a high prevalence and can be treated with a high success rate. However, melanoma, a rare type of skin cancer with a high mortality rate, can metastasize and invade other parts of the body. Various skin cancer treatment approaches have been developed and advanced from localized to systemic treatment over the years to improve the low success rate associated with skin cancer, especially metastatic melanoma. The systemic treatment of skin cancer is highly benefitted by drug delivery systems (DDS) designed to function with much higher specificity and lower side effects than the direct treatment with drugs. While many nanomaterials based DDS have been developed in the past few years to take advantage of the small size and high functionality of nanomaterials, silica-based nanomaterials have recently emerged as the flexible DDS with a high biocompatibility, good clearance, a high drug loading capacity, and versatility to attach several drugs and targeting agents to its surface. In this review, recent progress in the treatment of melanoma using silica-based nanomaterials and their hybrids is discussed, highlighting the versatility and potential of these emerging nanomaterials as the DDS for delivering various molecules, including drugs and immunotherapy agents, peptides, and radio- and photo-active agents. The review also introduces various therapies available for the treatment of melanoma, including surgery, chemotherapy, targeted therapy, phototherapy, and immunotherapy and discusses the improvement in these therapies based on silica-based DDS. The review also highlights the role of silica nanomaterials and their hybrids in delivering combination therapy and the advantages of silica nanohybrids over pure silica-based DDS. Finally, we summarize the present status of silica-based nanomaterials in melanoma treatment and the current challenges that have to be solved for the clinical translation of these materials as DDS.

Increasing competition for resources in small-scale fisheries (SSFs) can lead to overharvesting and threatens their sustainability. Sustainable management policies require engaging multiple resource users in decision-making processes, capturing diverse interests, and creating a platform for collaborative activities. This paper combines participatory modelling and systems thinking approaches to develop a joint stakeholder understanding of system structure, feedback mechanisms, and system archetypes of a SSF system in the Tam Giang Lagoon, located along the central coast of Vietnam. The model revealed the extent to which the dynamics of this SSF system were governed by nonlinear and cyclic feedback loops between social and ecological components. To manage complexity, the interactions between reinforcing and balancing feedback loops were distilled into four key system archetypes—Limits to growth, Fixes that fail, Success to the successful, and Tragedy of the commons—that provide crucial lenses to identify leverage points for effective management. The findings suggest that the possibilities to avoid the dominance of undesirable archetypes in this highly contested fishery system remain limited for both local resource users and managers because of cultural and socioeconomic constraints. Reducing intensified resource exploitation and expanding livelihood alternatives for communities are key towards more sustainable pathways for this common-pool resource system and other similar ones. This case study demonstrates the usefulness of an analytical approach that integrates participatory modelling with systems thinking with the ultimate goal of improving communication and collaboration among multiple stakeholders in complex socio-ecological situations.

To assess the impact of antibiotic use in aquaculture in Nha Trang bay, we conducted this study with the aim of assessing antibiotic resistance of opportunistic pathogenic bacteria isolated from water and sediment around shrimp/fish cages in the Nha Trang bay. 109 strains of Vibrio, Salmonella-Shigella and Aeromonas groups were isolated in the surrounding environment of farming areas in Dam Bay and Hon Mieu. Antimicrobial resistance test of these 109 strains showed that in the water environment in Dam Bay, TET (96.6%) and NIT (92.5%) were the two antibiotics with the highest rates of resistant bacteria while no bacteria were resistant to RIF. All 5 types of antibiotics had a statistically insignificant percentage of antibiotic-resistant bacteria in water samples at Hon Mieu, ranging from 33.3% to 68.9%. Also in the water environment, the rate of antibiotic-resistant bacteria in Dam Bay was not influenced by the distance to the cages (42.5–66.6%). Meanwhile, in Hon Mieu, the highest rate of resistant bacteria was observed at the distance of 200 m (100%) away from cages and the lowest rate at the distance of 100 m (20%). In the sediment environment around the cages, both the Dam Bay and Hon Mieu farming areas showed the highest rates of antibiotic-resistant bacteria against TET, NIF and RIF had the lowest rate of resistant bacteria. Among the total of 109 strains tested for antibiotic resistance, 2 strains labeled TCBS_HM200 m and SS_HM200 m were found to be resistant to all 5 tested antibiotics. These two strains were respectively identified as Vibrio harveyi and Oceanimonas sp.

Lung cancer is one of the most common cancers, affecting more than 2.1 million people across the globe every year. A very high occurrence and mortality rate of lung cancer have prompted active research in this area with both conventional and novel forms of therapies including the use of nanomaterials based drug delivery agents. Specifically, the unique physico-chemical and biological properties of porous nanomaterials have gained significant momentum as drug delivery agents for delivering a combination of drugs or merging diagnosis with targeted therapy for cancer treatment. This review focuses on the emergence of nano-porous materials for drug delivery in lung cancer. The review analyses the currently used nanoporous materials, including inorganic, organic and hybrid porous materials for delivering drugs for various types of therapies, including chemo, radio and phototherapy. It also analyses the selected research on stimuli-responsive nanoporous materials for drug delivery in lung cancer before summarizing the various findings and projecting the future of emerging trends. This review provides a strong foundation for the current status of the research on nanoporous materials, their limitations and the potential for improving their design to overcome the unique challenges of delivering drugs for the treatment of lung cancer.

While feathers are still commonly regarded in many places as waste, in many developed countries it has been considered a valuable by-product of the poultry industry. The poultry industry of Vietnam has achieved encouraging achievements in the past 10 years. The total flock of poultry from 100 million to now has reached nearly 467 million. Though light as a feather, with the vast quantities of chickens produced annually, the number of feathers produced is considerable. Research has shown that the feathers have hydrophobic properties and can therefore be used to make products that absorb oil. However, the use of large amounts of toxic detergents to clean chicken feathers in reported studies has reduced the environmental significance of agricultural waste reuse. In this study, we evaluated the possibility of replacing toxic cleaning agents with eco-friendly natural cleaners in the handling of chicken feathers. Water-based extracts of soapnuts and bo-ket fruits have been selected for our study due to their high saponin content - an effective cleaning agent, and have been used as a dishwashing liquid or shampoo for a long-time by local housewives. Our study showed that natural detergents derived from soapnuts have been shown the ability to remove lards on the plastic surface, and to clean chicken feathers, thereby increasing their capacity to absorb various oils including cooking oil, used cooking oil, and lubricant oil. We have also created an oil-absorbing pillow containing soapnut extract-treated chicken feathers with a maximum efficiency of 16.8 g/g in absorbing lubricant oil. Our research opens new avenues for the use and treatment of poultry feathers, contributing to the reduction of solid waste from the poultry industry by methods which is friendlier to the environment. The greenness of the created absorber is guaranteed.

Resonant power supplies have the advantage over traditional pulse widthmodulation (PWM) converters due to their soft switching capabilities. Inaddition, the output current ripple can be reduced by using three phaseinterleaving structure. However, this structure also suffers from somedisadvantages, such as resonant current imbalance. Most previous solutionshave been focused on hardware as adding extra power switches, increasingthe cost and volume of the converter. There are not many software solutionsdue to the difficulty in modeling unbalance three-phase. This paper willpropose a smoothly resonant current balancing solution for the three-phase interleaved LLC structure which is based on controlling directly resonantcurrent phase angles (CPAB). This proposed method shows better currentbalance and response than the old trigonometric current balancing (TCB)method. The proposed technique is also verified by a 48 V 3.6 kW prototypeconverter and its experimental results.

Land use/cover information is fundamental for the sustainable management of resources. Notwithstanding the advancement of remote sensing, analysts daunt to generate sufficient-quality land use/cover products due to dense-cloud-contaminated and/or technical issues. This study proposes a novel approach (Ensemble Learning Updating Classifier/ELUC), which can be applied with various classification algorithms and data sets to simplistically generate new classifications or renew existing classifications with a remarkable accuracy improvement. Applying miscellaneous features of Landsat-8 images, the ELUC of a random-forest-based algorithm produces sequences of single-time classifications with a mean overall accuracy of 84%. Through the study period, these sequences of individual classifications were then joined to achieve a final classification which reaches an overall accuracy of 94%. Also, the ELUC of the random-forest-based algorithm outperforms that of Kernel-Density-Estimation with a 5% overall accuracy higher. These outcomes confirm the effectiveness of the ELUC for a remarkably consistent land use/cover estimation with a data-rich environment.

Quantitative PCR and droplet digital PCR were elucidated as non-invasive methods for quantifying the level of signaling markers, such as CD3ɛ and IP-10 mRNAs from urine samples, for the diagnosis of acute rejection in the kidney allograft recipients. Although the sensitivity and accuracy make PCR as the gold standard for diagnosis, a point-of-care (POC) testing is required for the rapid and low-cost preliminary prognosis and diagnosis. In this study, the applicability of the cell-free platform-based toehold switch system was preliminary demonstrated for the detection of synthetic IP-10 mRNA, one of indicators of acute kidney allograft rejection. For POC applications, the colorimetric output was utilized for direct recognition by naked eyes. A total of 5 switches was screened from 289 putative toehold switches. Among these, the toehold switch 4 illustrated the highest fold change after a 45-min incubation with relatively high specificity. The sensitivity of the toehold switch 4 was also demonstrated with the cognate IP-10 mRNA. The results in this study showed the feasibility of the synthetic system of RNA toehold switches in combination with the cell-free platform as a preliminary prognostic and diagnostic method for acute kidney allograft rejection.

Infections with the zoonotic liver flukes Fasciola gigantica and Fasciola hepatica may result in severe disease in humans. In Vietnam, an emergence of fascioliasis cases has been observed from the late 1990s onwards. Various diagnostic tools are used in the country, but the agreement between these tools has not been critically evaluated. We aimed to describe the clinical presentation and diagnostic outcomes in fascioliasis patients in Vietnam. A retrospective, cross-sectional study was conducted on the medical records of a group of 145 patients diagnosed with fascioliasis at a tertiary referral hospital in Hanoi. Based on the review, sociodemographic background and clinical presentation were recorded. These patients all received standard routine serologic tests, including internal antibody (Ab)-ELISA, an enzyme-linked immunosorbent assay (ELISA), and commercial coproantigen (cAg)-ELISA. The majority of cases were between 30 and 59 years old (68.3%), and about half of them were male (51.0%). Upper quadrant and epigastric pain were the most commonly reported symptoms (61.4% and 35.2%, respectively). All but one patient had liver lesions upon ultrasound examination (99.3%), and eosinophilia was present in most of the patients (89.7%). A high number of patients were positive in the in-house and the commercial Ab-ELISA (95.9% and 87.4%, respectively), yet only a slight agreement was observed between the two tests (kappa coefficient, 0.06). A further 47.4% of cases were positive for the commercial cAg-ELISA, whereas stool microscopy indicated the presence of Fasciola spp. eggs in 25.7% of patients. The current study emphasizes the challenges related to the diagnosis of human fascioliasis in Vietnam.

Objectives: The purpose of this study was to identify the SNP sites and determine the BKV genotype circulating in kidney-transplant Vietnamese recipients based on the VP1 gene region. Methods: 344 samples were collected from post-kidney-transplant recipients at the 103 Vietnam Military Hospital to investigate the number of BKV infections. Positive samples with a sufficient virus concentration were analyzed by nested PCR in the VP1 region, sequencing detected genotyping and single-nucleotide polymorphism. Results: BKV infection was determined in 214 patients (62.2%), of whom 11 (5.1%) were diagnosed with BKV-associated nephropathy. Among the 90 BKV-I strains sequenced, 89 (98.88%) were strains of I/b-1 and 1 (1.12%) was strain I/b-2. The 60 BKV-IV strains had a greater diversity of subgroups, including 40% IV/a-1, 1.66% IV/a-2, 56.68% IV/c-1, and 1.16% IV/c-2. Additionally, of 11 cases diagnosed with BKVN, seven belonged to subgroup I/b-1 (63.6%) and four to subgroup IV/c-1 (36.4%). Moreover, 22 specific SNPs that were genotype I or IV were determined in this Vietnamese population. Specifically, at position 1745, for the Vietnamese BKV-IV strains, the SNP position (A→G) appeared in 57/60 samples (95%). This causes transformation of the amino acid N→S. This SNP site can enable detection of genotype IV in Vietnam. It represents a unique evolution pattern and mutation that has not been found in other international strains. Conclusion: The BKV-I genotype was more common than BKV-IV; however, mutations that occur on the VP1 typing region of BKV-IV strains were more frequent than in BKV-I strains.

The purpose of this study was to identify the SNP sites and determine the BKV genotype circulating in kidney-transplant Vietnamese recipients based on the VP1 gene region.344 samples were collected from post-kidney-transplant recipients at the 103 Vietnam Military Hospital to investigate the number of BKV infections. Positive samples with a sufficient virus concentration were analyzed by nested PCR in the VP1 region, sequencing detected genotyping and single-nucleotide polymorphism.BKV infection was determined in 214 patients (62.2%), of whom 11 (5.1%) were diagnosed with BKV-associated nephropathy. Among the 90 BKV-I strains sequenced, 89 (98.88%) were strains of I/b-1 and 1 (1.12%) was strain I/b-2. The 60 BKV-IV strains had a greater diversity of subgroups, including 40% IV/a-1, 1.66% IV/a-2, 56.68% IV/c-1, and 1.16% IV/c-2. Additionally, of 11 cases diagnosed with BKVN, seven belonged to subgroup I/b-1 (63.6%) and four to subgroup IV/c-1 (36.4%). Moreover, 22 specific SNPs that were genotype I or IV were determined in this Vietnamese population. Specifically, at position 1745, for the Vietnamese BKV-IV strains, the SNP position (A→G) appeared in 57/60 samples (95%). This causes transformation of the amino acid N→S. This SNP site can enable detection of genotype IV in Vietnam. It represents a unique evolution pattern and mutation that has not been found in other international strains.The BKV-I genotype was more common than BKV-IV; however, mutations that occur on the VP1 typing region of BKV-IV strains were more frequent than in BKV-I strains.

Methane is considered the carbon source with the highest potential in industrial biotechnology because of its abundance and sustainability. The biological conversion of methane into chemicals or fuels can not only reduce greenhouse gas emissions, but can also substitute edible substrates used in biorefineries. Methanotrophs that can utilize methane as the sole energy and carbon source play a significant role in the ecology of methane. Studies on metabolically-engineered methanotrophs have attracted extensive attention in recent years. In this chapter, the approaches and strategies of methanotrophic cell factory construction are summarized based on synthetic biology tools, systematic manipulation, metabolic modeling, and carbon flux enhancement. Finally, the challenges and opportunities for methane bioconversion by methanotrophs are discussed based on industrial applications.

Background Methylacidiphilum sp. IT6 has been validated its C3 substrate assimilation pathway via acetol as a key intermediate using the PmoCAB3, a homolog of the particulate methane monooxygenase (pMMO). From the transcriptomic data, the contribution of PmoD of strain IT6 in acetone oxidation was questioned. Methylomonas sp. DH-1, a type I methanotroph containing pmo operon without the existence of its pmoD, has been deployed as a biocatalyst for the gas-to-liquid bioconversion of methane and propane to methanol and acetone. Thus, Methylomonas sp. DH-1 is a suitable host for investigation. The PmoD-expressed Methylomonas sp. DH-1 can also be deployed for acetol production, a well-known intermediate for various industrial applications. Microbial production of acetol is a sustainable approach attracted attention so far. Results In this study, bioinformatics analyses elucidated that novel protein PmoD is a C-terminal transmembrane–helix membrane with the proposed function as a transport protein. Furthermore, the whole-cell biocatalyst was constructed in Methylomonas sp. DH-1 by co-expression the PmoD of Methylacidiphilum sp. IT6 with the endogenous pMMO to enable acetone oxidation. Under optimal conditions, the maximum accumulation, and specific productivity of acetol were 18.291 mM (1.35 g/L) and 0.317 mmol/g cell/h, respectively. The results showed the first coupling activity of pMMO with a heterologous protein PmoD, validated the involvement of PmoD in acetone oxidation, and demonstrated an unprecedented production of acetol from acetone in type I methanotrophic biocatalyst. From the data achieved in batch cultivation conditions, an assimilation pathway of acetone via acetol as the key intermediate was also proposed. Conclusion Using bioinformatics tools, the protein PmoD has been elucidated as the membrane protein with the proposed function as a transport protein. Furthermore, results from the assays of PmoD-heteroexpressed Methylomonas sp. DH-1 as a whole-cell biocatalyst validated the coupling activity of PmoD with pMMO to convert acetone to acetol, which also unlocks the potential of this recombinant biocatalyst for acetol production. The proposed acetone-assimilated pathway in the recombinant Methylomonas sp. DH-1, once validated, can extend the metabolic flexibility of Methylomonas sp. DH-1.

In this study, we aimed to explore the rural landscape transformation through the analysis of land use/land cover (LULC) spatio-temporal dynamics in the entire Vietnamese Mekong Delta over the three decades, using Landsat imageries and a supervised random forest classifier. Results indicated that in the 1990s, dominant LULC types were arable cropland, wetland, and permanent crops, which covered approximately half of the delta, 28% and 8%, respectively. From 1990 to 2019, the wetland area decreased from 28% to 5% due to the expansion of aquaculture and the arable cropland. The aquaculture, however, expanded more rapidly than other land use conversions, namely, from 2% to 19%. Although mangrove forests slightly recovered by 58 km2 from 2005 to 2019, the overall trend (1990-2019) showed an intense loss of 740 km2 due to widespread conversions into aquaculture. The paper unravels the complex dynamics between land-cover change, socio-economic development and associated land-use policies, which have significant implications for the change in rural landscapes.

Objective: The aim of this study was to evaluate VITROS(®) syphilis Treponema pallidum agglutination (VITROS(®) syphilis TPA) assay based on enhanced chemiluminescence principle for detection of syphilis infection in blood donors. Subject and method: A total of 110 random blood samples collected from the blood donors and 30 syphilis known sero-reactive samples stored at -20°C, were used to evaluate the performance of VITROS(®) syphilis TPA assay based on enhanced chemiluminescence assay on VITROS(®) immunodiagnostics system to analyze the terms of its sensitivity, precision, cross-reactivity and interference studies. Result: The results showed that VITROS(®) syphilis TPA got 100% sensitivity and specificity with precision (20 days study) of < 10% co-efficient of variation. There was no cross-reactivity with other viral and auto-immune antibodies. No interference was observed from endogenous interfering substances like free hemoglobin or fats. Conclusion: The results suggested that VITROS(®) syphilis TPA should be done to further reduce the risk of transfusion-transmitted TP infection, decrease unnecessary blood waste and loss of blood donors.

The subprime mortgage crisis in the United States (U.S.) in mid-2008 suggests that stock prices volatility do spillover from one market to another after international stock markets downturn. The purpose of this paper is to examine the magnitude of return and volatility spillovers from developed markets (the U.S. and Japan) to eight emerging equity markets (India, China, Indonesia, Korea, Malaysia, the Philippines, Taiwan, Thailand) and Vietnam. Employing a mean and volatility spillover model that deals with the U.S. and Japan shocks and day effects as exogenous variables in ARMA(1,1), GARCH(1,1) for Asian emerging markets, the study finds some interesting findings. Firstly, the day effect is present on six out of nine studied markets, except for the Indian, Taiwanese and Philippine. Secondly, the results of return spillover confirm significant spillover effects across the markets with different magnitudes. Specifically, the U.S. exerts a stronger influence on the Malaysian, Philippine and Vietnamese market compared with Japan. In contrast, Japan has a higher spillover effect on the Chinese, Indian, Korea, and Thailand than the U.S. For the Indonesian market, the return effect is equal. Finally, there is no evidence of a volatility effect of the U.S. and Japanese markets on the Asian emerging markets in this study.