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Antibiotic tolerance in Mycobacterium tuberculosis reduces bacterial killing, worsens treatment outcomes, and contributes to resistance. We studied rifampicin tolerance in isolates with or without isoniazid resistance (IR). Using a minimum duration of killing assay, we measured rifampicin survival in isoniazid-susceptible (IS, n=119) and resistant (IR, n=84) isolates, correlating tolerance with bacterial growth, rifampicin minimum inhibitory concentrations (MICs), and isoniazid-resistant mutations. Longitudinal IR isolates were analyzed for changes in rifampicin tolerance and genetic variant emergence. The median time for rifampicin to reduce the bacterial population by 90% (MDK90) increased from 1.23 days (IS) and 1.31 days (IR) to 2.55 days (IS) and 1.98 days (IR) over 15–60 days of incubation, indicating fast and slow-growing tolerant sub-populations. A 6 log10-fold survival fraction classified tolerance as low, medium, or high, showing that IR is linked to increased tolerance and faster growth (OR = 2.68 for low vs. medium, OR = 4.42 for low vs. high, p-trend = 0.0003). High tolerance in IR isolates was associated with rifampicin treatment in patients and genetic microvariants. These findings suggest that IR tuberculosis should be assessed for high rifampicin tolerance to optimize treatment and prevent the development of multi-drug-resistant tuberculosis.

The trend of educational innovation from a content approach to a competency approach raises the need to innovate teaching methods. For new innovation, learners need guidance and supports in practical activity. The ultimate goal of project-based learning is specific circuit, for applying knowledge to solve daily problems. Teaching STEM topics is to improve knowledge and skills in science, technology, engineering, and mathematics for learners. For Electronic Practice course, lessons are structured as projects to meet the requirement of STEM education. The article suggests that the knowledge and skills acquired through project-based teaching surpass those obtained through traditional teaching methods. In addition, it proposes experimenting with implementing project-based STEM method in the Electronics Practice course with three lessons specifically designed by integrating individual lessons. The STEM project-based teaching process for the lesson “Design and Assemble the regulator Power 5V DC” is presented, analyzed, and designed with completely new questionnaires. This will be a reference for lecturers while teaching the Electronics Practice course to innovate teaching methods to keep up with current development speed.

Abstract Specific antiferromagnetic (AF) spin configurations generate large anomalous Hall effects (AHEs) even at zero magnetic field through nonvanishing Berry curvature in momentum space. In addition to restrictions on AF structures, suitable control of AF domains is essential to observe this effect without cancellations among its domains; therefore, compatible materials remain limited. Here we show that an orthorhombic noncollinear AF material, NbMnP, acquired AF structure-based AHE and controllability of the AF domains. Theoretical calculations indicated that a large Hall conductivity of ~230 Ω−1cm−1 originated from the AF structure of NbMnP. Symmetry considerations explained the production of a small net magnetization, whose anisotropy enabled the generation and cancellation of the Hall responses using magnetic fields in different directions. Finally, asymmetric hysteresis in NbMnP shows potential for the development of controllability of responses in AF materials.

ABSTRACT A previous investigation has elucidated the landscape of Mtb genomic diversity and transmission dynamics in Ho Chi Minh City, Vietnam. Here, we expand the scope of this survey by adding a substantial number of additional genomes (total sample size: 2,542) and phenotypic drug susceptibility data for the majority of isolates. We aim to explore the prevalence and evolutionary dynamics of drug resistance and our ability to predict drug resistance from sequencing data. Among isolates tested phenotypically against first-line drugs, we observed high rates of streptomycin [STR, 37.7% (N = 573/1,520)] and isoniazid resistance [INH, 25.7% (N = 459/1,786)] and lower rates of resistance to rifampicin [RIF, 4.9% (N = 87/1,786)] and ethambutol [EMB, 4.2% (N = 75/1,785)]. Relative to global benchmarks, resistance to STR and INH was predicted accurately when applying the TB-Profiler algorithm to whole genome sequencing data (sensitivities of 0.81 and 0.87, respectively), while resistance to RIF and EMB was predicted relatively poorly (sensitivities of 0.70 and 0.44, respectively). Exploring the evolution of drug resistance revealed the main phylogenetic lineages to display differing dynamics and tendencies to evolve resistance via mutations in certain genes. The Beijing sublineage L2.2.1 was found to acquire de novo resistance mutations more frequently than isolates from other lineages and to suffer no apparent fitness cost acting to impede the transmission of resistance. Mutations conferring resistance to INH and STR arose earlier, on average, than those conferring resistance to RIF and are now more widespread across the phylogeny. The high prevalence of “background” INH resistance, combined with high rates of RIF mono-resistance (20.7%, N = 18/87), suggests that rapid assays for INH resistance will be valuable in this setting. These tests will allow the detection of INH mono-resistance and will allow multi-drug-resistant isolates to be distinguished from isolates with RIF mono-resistance. IMPORTANCE Drug-resistant tuberculosis (TB) infection is a growing and potent concern, and combating it will be necessary to achieve the WHO’s goal of a 95% reduction in TB deaths by 2035. While prior studies have explored the evolution and spread of drug resistance, we still lack a clear understanding of the fitness costs (if any) imposed by resistance-conferring mutations and the role that Mtb genetic lineage plays in determining the likelihood of resistance evolution. This study offers insight into these questions by assessing the dynamics of resistance evolution in a high-burden Southeast Asian setting with a diverse lineage composition. It demonstrates that there are clear lineage-specific differences in the dynamics of resistance acquisition and transmission and shows that different lineages evolve resistance via characteristic mutational pathways.

In this paper, the free vibration of the bi-dimensional functionally grated (2D-FG) size dependent nanobeams was investigated by finite element method. The material properties of 2D-FG nanobeam are assumed to vary in both axial and thickness directions by power gradation laws. The size-dependent 2D-FG nanobeam is studied on the basic of nonlocal continuum model. Based on the Euler-Bernoulli beam theory, a finite nanobeam element is derived and employed in vibration analysis of the beam. A parametric study has been carried out to show the effect of material distribution, nonlocal effect on the natural frequencies of the beams.

Abstract The human gut microbiota has been shown to be significantly perturbed by antibiotic use, while recovering to the pre-treatment state several weeks after short antibiotic exposure. The effects of antibiotics on the gut microbiota have however been mainly documented in high-income settings with lower levels of antibiotic resistance as compared to lower and middle income countries (LMIC). This study aimed to examine the long-term consequences of repeated exposure to commonly use antibiotics on the fecal microbiota of residents living in a low income setting with high prevalence of antibiotic resistance. Fecal samples from household individuals (n = 63) participating in a rural cohort in northern Vietnam were collected monthly for a period of 6 months. Using 16S V4 rRNA gene region amplicon sequencing and linear mixed-effects models analysis, we observed only a minor and transient effect of antibiotics on the microbial richness (ß = − 31.3, 95%CI = − 55.3, − 7.3, p = 0.011), while the microbial diversity was even less affected (ß = − 0.298, 95%CI − 0.686, 0.090, p = 0.132). Principal Component Analyses (PCA) did not reveal separation of samples into distinct microbiota-based clusters by antibiotics use, suggesting the microbiota composition was not affected by the antibiotics commonly used in this population. Additionally, the fecal microbial diversity of the subjects in our study cohort was lower when compared to that of healthy Dutch adults (median 3.95 (IQR 3.72–4.13) vs median 3.69 (IQR3.31–4.11), p = 0.028, despite the higher dietary fiber content in the Vietnamese as compared to western diet. Our findings support the hypothesis that frequent antibiotic exposure may push the microbiota to a different steady state that is less diverse but more resilient to disruption by subsequent antibiotic use.

The study explores new faculty socialization in Vietnam. At the same time, it seeks to understand the organizational culture of institutions of higher learning in Vietnam, particularly teacher education universities, through the dimension of socialization. An illustrative case study is used as it helps to focus on understanding a phenomenon in a given context-new faculty socialization in a Vietnamese university-especially when this phenomenon is as complex as the organizational culture whose parts socialization partially represents. The study also introduces the application of the three-level theory introduced by Schein to investigate matters regarding socialization, considered a dimension of organizational culture. The research showed that socialization mainly depends on the departments, as well as the learning history, skills, and proactivity of the faculty members. The institution has few strategies and activities to help new academics integrate into the work environment. From the organizational-culture perspective, there are various factors that influence the socialization process and are considered fundamental including norms for teacher trainers and hierarchical culture within the university.

Coal-fired power plant fly ash is a global environmental concern due to its small particle size, heavy metal content, and increased emissions. Although widely used in concrete, geopolymer, and fly ash brick production, a large amount of fly ash remains in storage sites or is used in landfills due to inadequate raw material quality, resulting in a waste of a recoverable resource. Therefore, the ongoing need is to develop new methods for recycling fly ash. The present review differentiates the physiochemical properties of fly ash from two coal combustion processes: fluidized bed combustion and pulverized coal combustion. It then discusses applications that can consume fly ash without strict chemical requirements, focusing on firing-associated methods. Finally, the challenges and opportunities of fly ash recycling are discussed.

Linezolid is an antibiotic of last resort for the treatment of infections caused by Gram-positive bacteria, including vancomycin-resistant enterococci. Enterococcus faecalis, a member of enterococci, is a significant pathogen in nosocomial infections. E. faecalis resistance to linezolid is frequently related to the presence of optrA, which is often co-carried with fex, phenicol exporter genes, and erm genes encoding macrolide resistance. Therefore, the common use of antibiotics in veterinary might promote the occurrence of optrA in livestock settings. This is a cross-sectional study aiming to investigate the prevalence of optrA positive E. faecalis (OPEfs) in 6 reservoirs in farms in Ha Nam province, Vietnam, and its associated factors and to explore genetic relationships of OPEfs isolates. Among 639 collected samples, the prevalence of OPEfs was highest in flies, 46.8% (51/109), followed by chickens 37.3% (72/193), dogs 33.3% (17/51), humans 18.7% (26/139), wastewater 16.4% (11/67) and pigs 11.3%, (14/80). The total feeding area and total livestock unit of the farm were associated with the presence of OPEfs in chickens, flies, and wastewater. Among 186 OPEfs strains, 86% were resistant to linezolid. The presence of optrA was also related to the resistant phenotype against linezolid and levofloxacin of E. faecalis isolates. Close genotypic relationships identified by Pulsed Field Gel Electrophoresis between OPEfs isolates recovered from flies and other reservoirs including chickens, pigs, dogs, and wastewater suggested the role of flies in the transmission of antibiotic-resistant pathogens. These results provided warnings of linezolid resistance although it is not used in livestock.

Abstract Background Antibiotic resistance is a major global public health threat. Antibiotic use can directly impact the antibiotic resistant genes (ARGs) profile of the human intestinal microbiome and consequently the environment through shedding. Methods We determined the resistome of human feces, animal stools, human food and environmental (rain, well, and irrigative water) samples (n = 304) in 40 households within a community cohort and related the data to antibiotic consumption. Metagenomic DNA was isolated and qPCR was used to determine presence of mobile colistin resistance (mcr) genes, genes encoding extended-spectrum β-lactamases (ESBL), carbapenemases and quinolone resistance genes. Results Nearly 40 % (39.5%, 120/304) of samples contained ESBL genes (most frequent were CTX-M-9 (23.7% [72/304]), CTX-M-1 (18.8% [57/304]). Quinolone resistance genes (qnrS) were detected in all human and 91% (41/45) of animal stool samples. Mcr-1 and mcr-3 were predominantly detected in human feces at 88% (82/93) and 55% (51/93) and animal feces at 93% (42/45) and 51% (23/45), respectively. Mcr-2, mrc-4 and mcr-5 were not detected in human feces, and only sporadically (

Cây Đìa đụm (Heliciopsis lobata (Merr.) Sleum) có nhiều tác dụng trong điều trị bệnh và được sử dụng rộng rãi trong các bài thuốc y học cổ truyền của người dân tộc thiểu số. Trong nghiên cứu này, dịch chiết methanol từ lá của cây Đìa đụm được sử dụng để đánh giá khả năng ức chế các tế bào ung thư vú và ung thư gan bằng phương pháp sàng lọc MTT, phân tích hình thái tế bào và hình thái kiểu nhân apoptosis bằng thuốc nhuộm nhân tế bào DAPI. Kết quả cho thấy dịch chiết methanol của lá cây Đìa đụm đã ức chế sự tăng sinh tế bào ung thư gan dòng HepG2 và ung vú dòng MCF7 với giá trị IC50 tương ứng là 0,084 mg/mL và 0,812 mg/mL. Dịch chiết này cảm ứng quá trình apoptosis đối với dòng tế bào HepG2 mạnh hơn so với dòng tế bào MCF7, và như vậy có tiềm năng chống lại sự tăng sinh của các tế bào ung thư gan.

BackgroundIn 2015, Singapore had the first and only reported foodborne outbreak of invasive disease caused by the group B Streptococcus (GBS; Streptococcus agalactiae). Disease, predominantly septic arthritis and meningitis, was associated with sequence type (ST)283, acquired from eating raw farmed freshwater fish. Although GBS sepsis is well-described in neonates and older adults with co-morbidities, this outbreak affected non-pregnant and younger adults with fewer co-morbidities, suggesting greater virulence. Before 2015 ST283 had only been reported from twenty humans in Hong Kong and two in France, and from one fish in Thailand. We hypothesised that ST283 was causing region-wide infection in Southeast Asia.Methodology/principal findingsWe performed a literature review, whole genome sequencing on 145 GBS isolates collected from six Southeast Asian countries, and phylogenetic analysis on 7,468 GBS sequences including 227 variants of ST283 from humans and animals. Although almost absent outside Asia, ST283 was found in all invasive Asian collections analysed, from 1995 to 2017. It accounted for 29/38 (76%) human isolates in Lao PDR, 102/139 (73%) in Thailand, 4/13 (31%) in Vietnam, and 167/739 (23%) in Singapore. ST283 and its variants were found in 62/62 (100%) tilapia from 14 outbreak sites in Malaysia and Vietnam, in seven fish species in Singapore markets, and a diseased frog in China.ConclusionsGBS ST283 is widespread in Southeast Asia, where it accounts for a large proportion of bacteraemic GBS, and causes disease and economic loss in aquaculture. If human ST283 is fishborne, as in the Singapore outbreak, then GBS sepsis in Thailand and Lao PDR is predominantly a foodborne disease. However, whether transmission is from aquaculture to humans, or vice versa, or involves an unidentified reservoir remains unknown. Creation of cross-border collaborations in human and animal health are needed to complete the epidemiological picture.

Scrub typhus has been documented since 1932 in Vietnam, however, the disease burden of scrub typhus remains poorly understood in the country. We conducted this study to describe the phylogenetic analysis of the 56-kDa type-specific antigen (TSA) gene of Orientia tsutsugamushi associated with PCR positive cases of scrub typhus. Of 116 positive samples, 65 type-specific antigen gene sequences were obtained and classified into 3 genogroups: Karp, Kato and Gilliam. The Karp genogroup was the most frequently detected phylogenetic cluster in the study with 30 samples (46%), followed by Kato and Gilliam with 20 (31%) and 15 (23%), respectively. All sequences showed 94-100% nucleotide similarity to reference sequences collected in the central part of Vietnam in 2017. Patients infected with Karp genogroup were more likely to have significant thrombocytopenia than the other genogroups. These results suggest that any scrub typhus vaccine considered for use in Vietnam should provide protection against each of these 3 genogroups.

This paper investigates the role of attitudes (positive and negative attitude), motivation (instrumental and integrative motivation), and language learning strategies (direct and indirect strategies) in learning English as a Foreign Language (EFL) among Vietnamese college students. The study involved 193 male and female freshman and sophomore college students majoring in English, Psychology, and Sociology in a university in Ho Chi Minh City, Vietnam. The study employed a mixed-method research design, namely quantitative and qualitative. The former consists of a survey design, which involved administering two different survey questionnaires: Attitude/Motivation Test Battery (AMTB) developed by Gardner (1995) to measure the attitudes and motivations toward EFL, and the Strategy Inventory for Language Learning (SILL) developed by Oxford (1990) to measure language learning strategies. A semi-structured interview with 45 participants was also conducted to verify the veracity of the responses to the questionnaires. The results of the study revealed that Vietnamese EFL college students tend to have significant positive attitudes toward English, and they appear to be instrumentally and integratively motivated to learn the said language. Interestingly, the findings showed that there is a significant difference between males’ and females’ attitudes toward EFL; however, there is no significant difference found in motivation and language learning strategies between male and female students. Furthermore, the results revealed that at the p¬

This paper describes the route, from simulations toward experiments, for optimizing the magnetoelectric (ME) geometries for vortex magnetic field sensors. The research is performed on the base of the Metglas/Piezoelectric (PZT) laminates in both open and closed magnetic circuit (OMC and CMC) geometries with different widths (W), lengths (L), and diameters (D). Among these geometries, the CMC laminates demonstrate advantages not only in their magnetic flux distribution, but also in their sensitivity and in their independence of the position of the vortex center. In addition, the ME voltage signal is found to be enhanced by increasing the magnetostrictive volume fraction. Optimal issues are incorporated to realize a CMC-based ME double sandwich current sensor in the ring shape with D × W = 6 mm × 1.5 mm and four layers of Metglas. At the resonant frequency of 174.4 kHz, this sensor exhibits the record sensitivity of 5.426 V/A as compared to variety of devices such as the CMC ME sensor family, fluxgate, magnetoresistive, and Hall-effect-based devices. It opens a potential to commercialize a new generation of ME-based current and (or) vortex magnetic sensors.

Action research in education is a study that educational practitioners carry out with the aim that they will be able to make better judgments and take better actions in their respective fields of competence after completing the study. When teachers completely comprehend their students' thoughts and feelings, they can communicate more effectively with their students. One of the key objectives of this study was to examine how teachers and administrators perceived their quality and talents in educational action research in order to improve their practice. The survey process for this study included 245 administrators and instructors from 11 high schools in Binh Duong City, Vietnam, who answered questions about their experiences. The findings presented above are critical for school administrators, teachers, and other stakeholders to consider developing methods to improve the quality and capacities of teachers involved in educational action research and reflect on their perceptions. These findings contribute to the action of applied scientific research in Vietnam. This will enable educational science research in Vietnam to become more and more practical.

During an outbreak of severe acute respiratory infections in 2 orphanages, Vietnam, 7/12 hospitalized children died. All hospitalized children and 26/43 children from outbreak orphanages tested positive for rhinovirus versus 9/40 control children (p = 0.0005). Outbreak rhinoviruses formed a distinct genetic cluster. Human rhinovirus is an underappreciated cause of severe pneumonia in vulnerable groups.

It is unclear why the severity of influenza varies in healthy adults or why the burden of severe influenza shifts to young adults when pandemic strains emerge. One possibility is that cross-protective T cell responses wane in this age group in the absence of recent infection. We therefore compared the acute cellular immune response in previously healthy adults with severe versus mild pandemic H1N1 infection.49 previously healthy adults admitted to the National Hospital of Tropical Diseases, Viet Nam with RT-PCR-confirmed 2009 H1N1 infection were prospectively enrolled. 39 recovered quickly whereas 10 developed severe symptoms requiring supplemental oxygen and prolonged hospitalization. Peripheral blood lymphocyte subset counts and activation (HLADR, CD38) and differentiation (CD27, CD28) marker expression were determined on days 0, 2, 5, 10, 14 and 28 by flow cytometry. NK, CD4 and CD8 lymphopenia developed in 100%, 90% and 60% of severe cases versus 13% (p

Mycobacterium tuberculosis , the causative agent of tuberculosis (TB), remains a global health burden. While M. tuberculosis is primarily a respiratory pathogen, it can spread to other organs, including the brain and meninges, causing TB meningitis (TBM). However, little is known about the immunological mechanisms that lead to differential disease across organs. Attention has focused on differences in T cell responses in the control of M. tuberculosis in the lungs, but emerging data point to a role for antibodies, as both biomarkers of disease control and as antimicrobial molecules. Given an increasing appreciation for compartmentalized antibody responses across the blood–brain barrier, here we characterized the antibody profiles across the blood and brain compartments in TBM and determined whether M. tuberculosis -specific humoral immune responses differed between M. tuberculosis infection of the lung (pulmonary TB) and TBM. Using a high throughput systems serology approach, we deeply profiled the antibody responses against 10 different M. tuberculosis antigens, including lipoarabinomannan (LAM) and purified protein derivative (PPD), in HIV-negative adults with pulmonary TB (n = 10) versus TBM (n = 60). Antibody studies included analysis of immunoglobulin isotypes (IgG, IgM, IgA) and subclass levels (IgG1–4) and the capacity of M. tuberculosis -specific antibodies to bind to Fc receptors or C1q and to activate innate immune effector functions (complement and natural killer cell activation; monocyte or neutrophil phagocytosis). Machine learning methods were applied to characterize serum and CSF responses in TBM, identify prognostic factors associated with disease severity, and define the key antibody features that distinguish TBM from pulmonary TB. In individuals with TBM, we identified CSF-specific antibody profiles that marked a unique and compartmentalized humoral response against M. tuberculosis , characterized by an enrichment of M. tuberculosis -specific antibodies able to robustly activate complement and drive phagocytosis by monocytes and neutrophils, all of which were associated with milder TBM severity at presentation. Moreover, individuals with TBM exhibited M. tuberculosis -specific antibodies in the serum with an increased capacity to activate phagocytosis by monocytes, compared with individuals with pulmonary TB, despite having lower IgG titres and Fcγ receptor-binding capacity. Collectively, these data point to functionally divergent humoral responses depending on the site of infection (i.e. lungs versus brain) and demonstrate a highly compartmentalized M. tuberculosis -specific antibody response within the CSF in TBM. Moreover, our results suggest that phagocytosis- and complement-mediating antibodies may promote attenuated neuropathology and milder TBM disease. [ABSTRACT FROM AUTHOR]

In this work, DyFeO3 nanoparticles were synthesized by an improved co-precipitation method via the hydrolysis of Dy3+ and Fe3+ cations in boiling water, using a 5% ammonia solution as the precipitation agent. The physicochemical characteristics of the samples calcined at 750, 850, and 950 °C for 60 min were evaluated using FTIR, Raman, PXRD, EDX, SEM, TEM, DRS, and VSM methods. The stable single-phase DyFeO3 perovskite nanocrystals were obtained after calcination of the dried precursor at 750, 850, and 950 °C. According to PXRD, the average size of DyFeO3 crystals was calculated to be approximately 36–50 nm. The results revealed a homogeneous distribution of the main elements on the samples’ surfaces, with morphology consisting of isometric and highly agglomerated nanoparticles; the size of most DyFeO3 nanoparticles calcined at 850 °C distributed in the range of 30–50 nm. In the applied field from − 15 to + 15 kOe, the sample calcined at 850 and 950 °C had low values of coercive field (Hc = 1.4 × 10−2–1.8 × 10−2 Oe) and remanent magnetization (Mr = 1.10 × 10−7–0.54 × 10−7 emu g−1, but high values of net magnetization (Mn = 2.69–2.75 emu g−1); the samples appeared to behave as paramagnetic materials. The DyFeO3-850 °C and DyFeO3-950 °C samples demonstrated a high absorbance at wavelengths of 400–600 nm, with low values of direct bandgap (Eg = 2.31–2.15 eV). [ABSTRACT FROM AUTHOR]

Background: Selecting embryos with the highest implantation potential is crucial for in vitro fertilization (IVF) success. Both the timing of blastulation, day 5 (D5) or D6, and the embryo quality have been suggested as influential factors in determining the clinical outcome of single euploid blastocyst transfers. However, evidence supporting the superiority of D5 over D6 blastocysts remains inconclusive. The aim of this study was to compare clinical outcomes following the transfer of euploid blastocysts with different quality and timing of blastulation. Materials and Methods: A retrospective cohort study was conducted at our Assisted Reproductive Center, analyzing the outcome of 774 transfers with D5 euploids and 155 transfers with D6 euploids performed between January 2019 and February 2022. Results: The live birth rate was significantly lower in the euploid D6 group compared to the euploid D5 group (38.71vs. 55.04%, P=0.001). The outcome was significantly influenced by the quality of the embryos. Live birth rates were 62.14 and 53.61% following transfers of D5 and D6 excellent embryos respectively, 45.18 and 32.21% following transfer of D5 and D6 good embryos but only 28.64 and 19.32% following transfer of D5 and D6 fair embryos. The outcome difference was statistically significant across embryo quality categories (P=0.001). The adjusted risk ratios (RR) of clinical outcomes indicated that excellent euploid D5 embryos consistently outperformed other types of embryo quality. Conclusion: The timing of blastulation and embryo quality are crucial factors in determining the success of single euploid blastocyst transfers. Excellent euploid D5 transfers yielded superior clinical outcomes, providing valuable insights for IVF teams and patients when selecting embryos to be transferred. [ABSTRACT FROM AUTHOR]