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Siderophores belonging to the ferrichrome family are essential for the viability of fungal species and play a key role for virulence of numerous pathogenic fungi. Despite their biological significance, our understanding of how these iron-chelating cyclic hexapeptides are assembled by non-ribosomal peptide synthetase (NRPS) enzymes remains poorly understood, primarily due to the nonlinearity exhibited by the domain architecture. Herein, we report the biochemical characterization of the SidC NRPS, responsible for construction of the intracellular siderophore ferricrocin. In vitro reconstitution of purified SidC reveals its ability to produce ferricrocin and its structural variant, ferrichrome. Application of intact protein mass spectrometry uncovers several non-canonical events during peptidyl siderophore biosynthesis, including inter-modular loading of amino acid substrates and an adenylation domain capable of poly-amide bond formation. This work expands the scope of NRPS programming, allows biosynthetic assignment of ferrichrome NRPSs, and sets the stage for reprogramming towards novel hydroxamate scaffolds.

Syntrophy is essential for the efficient conversion of organic carbon to methane in natural and constructed environments, but little is known about the enzymes involved in syntrophic carbon and electron flow. Syntrophus aciditrophicus strain SB syntrophically degrades benzoate and cyclohexane-1-carboxylate and catalyses the novel synthesis of benzoate and cyclohexane-1-carboxylate from crotonate. We used proteomic, biochemical and metabolomic approaches to determine what enzymes are used for fatty, aromatic and alicyclic acid degradation versus for benzoate and cyclohexane-1-carboxylate synthesis. Enzymes involved in the metabolism of cyclohex-1,5-diene carboxyl-CoA to acetyl-CoA were in high abundance in S. aciditrophicus cells grown in pure culture on crotonate and in coculture with Methanospirillum hungatei on crotonate, benzoate or cyclohexane-1-carboxylate. Incorporation of 13 C-atoms from 1-[13 C]-acetate into crotonate, benzoate and cyclohexane-1-carboxylate during growth on these different substrates showed that the pathways are reversible. A protein conduit for syntrophic reverse electron transfer from acyl-CoA intermediates to formate was detected. Ligases and membrane-bound pyrophosphatases make pyrophosphate needed for the synthesis of ATP by an acetyl-CoA synthetase. Syntrophus aciditrophicus, thus, uses a core set of enzymes that operates close to thermodynamic equilibrium to conserve energy in a novel and highly efficient manner.

Covalently cross-linked pilus polymers displayed on the cell surface of Gram-positive bacteria are assembled by class C sortase enzymes. These pilus-specific transpeptidases located on the bacterial membrane catalyze a two-step protein ligation reaction, first cleaving the LPXTG motif of one pilin protomer to form an acyl-enzyme intermediate and then joining the terminal Thr to the nucleophilic Lys residue residing within the pilin motif of another pilin protomer. To date, the determinants of class C enzymes that uniquely enable them to construct pili remain unknown. Here, informed by high-resolution crystal structures of corynebacterial pilus-specific sortase (SrtA) and utilizing a structural variant of the enzyme (SrtA2M), whose catalytic pocket has been unmasked by activating mutations, we successfully reconstituted in vitro polymerization of the cognate major pilin (SpaA). Mass spectrometry, electron microscopy, and biochemical experiments authenticated that SrtA2M synthesizes pilus fibers with correct Lys-Thr isopeptide bonds linking individual pilins via a thioacyl intermediate. Structural modeling of the SpaA-SrtA-SpaA polymerization intermediate depicts SrtA2M sandwiched between the N- and C-terminal domains of SpaA harboring the reactive pilin and LPXTG motifs, respectively. Remarkably, the model uncovered a conserved TP(Y/L)XIN(S/T)H signature sequence following the catalytic Cys, in which the alanine substitutions abrogated cross-linking activity but not cleavage of LPXTG. These insights and our evidence that SrtA2M can terminate pilus polymerization by joining the terminal pilin SpaB to SpaA and catalyze ligation of isolated SpaA domains in vitro provide a facile and versatile platform for protein engineering and bio-conjugation that has major implications for biotechnology.

Archaea use flagella known as archaella-distinct both in protein composition and structure from bacterial flagella-to drive cell motility, but the structural basis of this function is unknown. Here, we report an atomic model of the archaella, based on the cryo electron microscopy (cryoEM) structure of the Methanospirillum hungatei archaellum at 3.4 Å resolution. Each archaellum contains ∼61,500 archaellin subunits organized into a curved helix with a diameter of 10 nm and average length of 10,000 nm. The tadpole-shaped archaellin monomer has two domains, a β-barrel domain and a long, mildly kinked α-helix tail. Our structure reveals multiple post-translational modifications to the archaella, including six O-linked glycans and an unusual N-linked modification. The extensive interactions among neighbouring archaellins explain how the long but thin archaellum maintains the structural integrity required for motility-driving rotation. These extensive inter-subunit interactions and the absence of a central pore in the archaellum distinguish it from both the bacterial flagellum and type IV pili.

Syntrophus aciditrophicus is a model syntrophic bacterium that degrades key intermediates in anaerobic decomposition, such as benzoate, cyclohexane-1-carboxylate, and certain fatty acids, to acetate when grown with hydrogen-/formate-consuming microorganisms. ATP formation coupled to acetate production is the main source for energy conservation by S. aciditrophicus However, the absence of homologs for phosphate acetyltransferase and acetate kinase in the genome of S. aciditrophicus leaves it unclear as to how ATP is formed, as most fermentative bacteria rely on these two enzymes to synthesize ATP from acetyl coenzyme A (CoA) and phosphate. Here, we combine transcriptomic, proteomic, metabolite, and enzymatic approaches to show that S. aciditrophicus uses AMP-forming, acetyl-CoA synthetase (Acs1) for ATP synthesis from acetyl-CoA. acs1 mRNA and Acs1 were abundant in transcriptomes and proteomes, respectively, of S. aciditrophicus grown in pure culture and coculture. Cell extracts of S. aciditrophicus had low or undetectable acetate kinase and phosphate acetyltransferase activities but had high acetyl-CoA synthetase activity under all growth conditions tested. Both Acs1 purified from S. aciditrophicus and recombinantly produced Acs1 catalyzed ATP and acetate formation from acetyl-CoA, AMP, and pyrophosphate. High pyrophosphate levels and a high AMP-to-ATP ratio (5.9 ± 1.4) in S. aciditrophicus cells support the operation of Acs1 in the acetate-forming direction. Thus, S. aciditrophicus has a unique approach to conserve energy involving pyrophosphate, AMP, acetyl-CoA, and an AMP-forming, acetyl-CoA synthetase. Bacteria use two enzymes, phosphate acetyltransferase and acetate kinase, to make ATP from acetyl-CoA, while acetate-forming archaea use a single enzyme, an ADP-forming, acetyl-CoA synthetase, to synthesize ATP and acetate from acetyl-CoA. Syntrophus aciditrophicus apparently relies on a different approach to conserve energy during acetyl-CoA metabolism, as its genome does not have homologs to the genes for phosphate acetyltransferase and acetate kinase. Here, we show that S. aciditrophicus uses an alternative approach, an AMP-forming, acetyl-CoA synthetase, to make ATP from acetyl-CoA. AMP-forming, acetyl-CoA synthetases were previously thought to function only in the activation of acetate to acetyl-CoA.

Atherosclerotic disease occurs due to lifestyle choices, such as being sedentary, eating fast foods, and a lack of physical exercise. Atherosclerosis has gradually become the leading cause of death worldwide. Currently, the trend of using natural herbal products to supplement and replace synthetic drugs is being considered in Vietnam. This study aims to evaluate the in vivo anti-atherosclerotic effect of a mixture extract of C. chrysantha, G. pentaphyllum, and C. hindsii in a Wistar rat model. Wistar rats were randomly assigned to 5 groups with 10 animals in each group and blood samples were obtained from rats at 0, 14, and 28 days after treatment began to examine blood lipid indicators: triglyceride (TG), total cholesterol (TC), high-density lipoproteins (HDL-C), and low-density lipoproteins (LDL-C). The results showed that a mixture of C. chrysantha, G. pentaphyllum, and C. hindsii extracts at doses of 16.8 and 33.6 g/kg/day reduced blood lipid test indexes, including triglyceride levels, total cholesterol, LDL-cholesterol, and atherogenic index. At the same time, this mixture increased the levels of HDL-cholesterol in the blood, reduced the incidence of fatty liver, and protected against atherosclerotic lesions of the abdominal aorta in the studied rats. These initial findings contribute to the search for new sources of raw materials and the development of natural products to prevent and treat atherosclerosis. [ABSTRACT FROM AUTHOR]

This dataset delves into the intricate dynamics linking organizational commitment (OC) and job performance (JP) within the realm of State-Owned Enterprises (SOEs). Centering on the water supply industry, it seeks to unravel the nuances of organizational citizenship behavior (OCB) in an economy oriented by socialist values. The compilation of this dataset represents a balanced integration of qualitative and quantitative methodologies, incorporating insights from expert interviews alongside data gathered from employee surveys. It encompasses 336 valid responses, which have been meticulously analyzed through Partial Least Squares Structural Equation Modeling (PLS-SEM). This approach facilitates a deeper understanding of the interconnections between OC, OCB, and EP. The dataset is instrumental in highlighting the pivotal role of professional integrity and voluntary dedication within SOEs, underscoring their critical function in representing state interests and effectively serving the public.

Background Collecting and storing large number of sputum samples with a view to culturing these in the future requires an efficient initial handling method. We devised a modified sputum digestion and decontamination method that maximised storage capacity and Mycobacterium tuberculosis (M.tb) recovery from culture while minimising laboratory workload and risk of contamination. Methods We collected smear microscopy positive sputum samples from patients with pulmonary tuberculosis (TB). The sputum samples were split and processed using both the standard N-Acetyl-L-cysteine and sodium hydroxide (NALC-NaOH) method and our modified method before freezing and later culturing in BD BACTEC 960 Mycobacterium Growth Indicator Tubes (MGIT) system. We assessed the Time to Positivity (TPP) and Growth Unit (GU) data. Results We selected 22 sputum samples to compare two digestion and decontamination methods. The samples that underwent the modified method had longer TTP (p < 0.05) but similar GU in comparison to standard method. Overall, 1/22 samples failed to grow in MGIT after being processed by the modified method. We then applied the modified method to 348 sputum samples with Rifampicin resistance detected by GeneXpert MTB/RIF assay, which were frozen for between 1-25 months. The overall MGIT positive, negative, and contamination rate was 90.5%, 7.8%, and 1.7%, respectively. There was no significant difference in MGIT result when samples were grouped by duration of storage or positive smear grade. Conclusions Our modified method yielded acceptable M.tb recovery rate and low contamination risk while allowing us to collect and store thousands of sputum samples over a long period of time for future tests.

The aim of this study is to examine the relationship between work motivation and employee performance in sales, consulting, and service through the mediating role of Organizational Citizenship Behavior (OCB) at auto tire service companies. Motivation, a basic psychological process with the integration of other factors of perception, personality, attitude, and learning, is a critical component of behavior (Miner, Ebrahimi, & Wachtel, 1995). OCB is explained by Robbins and Judge (2017) as voluntary conduct that is not part of workers’ formal job requirements but enhances the organization’s effectiveness. Job performance is defined as the efficacy of a person’s work as indicated through behavioral elements connected to the organization’s goals. The primary data is collected by direct surveys of 300 employees with tenure five years of experience in auto tire service companies in Ho Chi Minh City, Dong Nai, and Binh Thuan Provinces. Partial Least Square Structural Equation Modeling (PLS-SEM) was employed to examine the structural relationships of the study. The findings indicate that work motivation has a positive direct relationship with OCB and job performance through the mediating effect of OCB. The results contribute to the current understanding of organizational behavior theory and practical contribution to human resource practices of business in the industry.

Al82Fe16Ce2 and Al82Fe14Mn2Ce2 amorphous alloys were successfully synthesized by the mechanical alloying technique. The microstructural evolution of the milled powders was thoroughly investigated employing X-ray diffraction (XRD) and scanning electron microscopy (SEM). Additionally, their magnetic properties were quantitatively evaluated by a vibrating sample magnetometer (VSM). A full amorphous structure was obtained for both alloys after milling for 40 h. During the initial milling stage, extending from 5 to 20 h, an fcc solid solution phase was formed, coexisting with the residual Al phase. The partial substitution of 2 atomic percent (at.%) Mn for Fe in Al82Fe16Ce2 did not affect the alloy’s glass-forming ability. The amorphous Al82Fe16Ce2 and Al82Fe14Mn2Ce2 powders exhibited a nearly spherical shape, with diameters ranging from 1 to 3 µm and to 10 µm, respectively. Additionally, both the Al82Fe16Ce2 and Al82Fe14Mn2Ce2 alloys demonstrated characteristics of hard magnetism.

Covalently cross-linked pilus polymers displayed on the cell surface of Gram-positive bacteria are assembled by class C sortase enzymes. These pilus-specific transpeptidases located on the bacterial membrane catalyze a two-step protein ligation reaction, first cleaving the LPXTG motif of one pilin protomer to form an acyl-enzyme intermediate and then joining the terminal Thr to the nucleophilic Lys residue residing within the pilin motif of another pilin protomer. To date, the determinants of class C enzymes that uniquely enable them to construct pili remain unknown. Here, informed by high-resolution crystal structures of corynebacterial pilus-specific sortase (SrtA) and utilizing a structural variant of the enzyme (SrtA2M), whose catalytic pocket has been unmasked by activating mutations, we successfully reconstituted in vitro polymerization of the cognate major pilin (SpaA). Mass spectrometry, electron microscopy, and biochemical experiments authenticated that SrtA2M synthesizes pilus fibers with correct Lys–Thr isopeptide bonds linking individual pilins via a thioacyl intermediate. Structural modeling of the SpaA–SrtA–SpaA polymerization intermediate depicts SrtA2M sandwiched between the N- and C-terminal domains of SpaA harboring the reactive pilin and LPXTG motifs, respectively. Remarkably, the model uncovered a conserved TP(Y/L)XIN(S/T)H signature sequence following the catalytic Cys, in which the alanine substitutions abrogated cross-linking activity but not cleavage of LPXTG. These insights and our evidence that SrtA2M can terminate pilus polymerization by joining the terminal pilin SpaB to SpaA and catalyze ligation of isolated SpaA domains in vitro provide a facile and versatile platform for protein engineering and bio-conjugation that has major implications for biotechnology. [ABSTRACT FROM AUTHOR]

Juvenile granulosa cell tumor (GCT) is a rare ovarian tumor in children, presenting with a multiloculated cystic pattern and irregular wall-thickening on imaging and serous cystadenoma (SCA) is also another rare benign cystic ovarian tumor in children. The appearance of two uncommon types of ovarian tumors on both sides in children is extremely rare. We report the case of a 4-year-old female presenting with symptoms of precocious puberty and diagnosed with juvenile GCT on the left ovary after surgical resection. However, during follow-up 1 year after GCT resection, she presented with another multiloculated cystic mass in the right ovary, and diagnosed as SCA after surgical resection and histopathologic evaluations. The appearance of cystic ovarian tumor after primarily GCT resection need to differentiate between the recurrence of the primarily GCT and other cystic ovarian tumors although it is very uncommon. Furthermore, the imaging features played a key role in the differential diagnosis between benign and malignant ovarian tumors.

Mặc dù, hoạt động thu hút FDI từ ASEAN vào ngành dịch vụ của Việt Nam đã đạt được nhiều thành tựu, tuy nhiên, thực trạng đầu tư nước ngoài từ khu vực này được đánh giá vẫn chưa tương xứng với tiềm năng hợp tác của các thành viên ASEAN, đặc biệt là trong bối cảnh các quốc gia đã và đang triển khai sâu rộng các cam kết hội nhập Cộng đồng Kinh tế ASEAN (AEC). Trong bài viết này, tác giả phân tích tổng quan tình hình nghiên cứu, bao gồm các nghiên cứu lý thuyết về thu hút FDI và các nghiên cứu thực nghiệm liên quan đến chủ đề này. Trong khi các nghiên cứu về lý thuyết thu hút FDI rất đa dạng và tương đối hoàn chỉnh nhằm chỉ ra được các yếu tố ảnh hưởng đến quyết định lựa chọn địa điểm đầu tư, thì các nghiên cứu thực nghiệm trong ngành dịch vụ tại Việt Nam mới chủ yếu thống kê phân tích thực trạng. Số lượng các nghiên cứu sử dụng phương pháp định lượng còn hạn chế và chưa có nghiên cứu thực nghiệm chỉ ra các yếu tố thu hút FDI từ ASEAN vào ngành dịch vụ của Việt Nam. Nghiên cứu thu hút FDI từ một số thành viên ASEAN vào ngành dịch vụ tại Việt Nam trong bối cảnh AEC - thực trạng, các yếu tố ảnh hưởng và giải pháp - với phương pháp nghiên cứu định lượng sử dụng các lý thuyết FDI là cách tiếp cận riêng của bài viết này.

The aim of this study was to determine the proper combination of nitrogen (N) fertilizer level and nitrogen fixing endophytic bacteria (NFEB) supplementation for the maximum grain yield of sesame cultivated in alluvial soil in dykes. The experiment followed a completely randomized block design with two factors. The first one was the levels of N fertilizer used, including 0, 50, 75, and 100% N of recommended fertilizer formula (RFF), and the other consisted of no bacteria applied, an individual strain of Enterobacter cloacae ASD-48 or E. cloacae ASD-21 applied, and their mixture, with 5 replicates. The results revealed that fertilizing with 100% N of RFF led to an enhancement of the plant height (16.8 cm), the chlorophyll a and b and their total content (6.45, 1.86, and 8.30 μg mL−1), the number of capsules per plant (7.22 capsules plant−1), the total N uptake (126.5 mg N pot−1), and the grain yield (9.08 g pot−1), in comparison to no N fertilizer applied. Supplementation of two NFRB strains enhanced the soilconcentrations of NH4+ and NO3−, the total N uptake, and the grain yield. The treatment fertilized with 75% N of RFF plus an individual NFEB strain or their bacterial mixture had equivalent total N uptake to that the treatment fertilized with 100% N of RFF had, 120.8–125.5 mg N pot−1 compared to 124.4 mg N pot−1. Regarding the sesame yield, with a reduction by 25–50% N of RFF plus ASD-48 and ASD-21, either individually or in mixture, it increased by 2.39–8.56%, compared to that in the treatment fertilized with 100% N of RFF.

Nghiên cứu được thực hiện nhằm mục tiêu: (i) xác định ảnh hưởng của bón khuyết NPK lên sinh trưởng, năng suất và hấp thu dinh dưỡng NPK trong cây mè; (ii) đánh giá khả năng cung cấp dưỡng chất bản địa của đất. Thí nghiệm bố trí theo khối hoàn toàn ngẫu nhiên gồm 4 nghiệm thức (i) bón đầy đủ N, P, K, (ii) Bón khuyết kali, (iii) bón khuyết lân, (iv) bón khuyết đạm, với 4 lặp lại. Kết quả nghiên cứu cho thấy đáp ứng năng suất của bón N, P2O5 và K2O được xác định là 34,38, 3,93 và 1,35 g m-2. Bón đạm giúp tăng năng suất hạt mè thông qua tăng số trái trên cây. Ngoài ra, bón lân hoặc kali chỉ tăng chiều cao cây và số trái, nhưng chưa tăng năng suất mè. Lượng hấp thu N, P và K ở nghiệm thức bón đầy đủ NPK lần lượt là 4,43, 2,05 và 5,75 g m-2. Tổng lượng N, P và K đất phù sa có khả năng cung cấp là 2,31, 1,28 và 3,96 g m-2.

Background: Estimating the cost of postoperative respiratory complications is crucial in developing appropriate strategies to mitigate the global and national economic burden. However, systematic analysis of the economic burden in low- and middle-income countries is lacking. Methods: We used the nationwide database of the Vietnam Social Insurance agency and extracted data from January 2017 to September 2018. The data contain 1 241 893 surgical patients undergoing one of seven types of surgery. Propensity score matching method was used to match cases with and without complications. We used generalized gamma regressions to estimate the direct medical costs; logistic regressions to evaluate the impact of postoperative respiratory complications on re-hospitalization and outpatient visits. Findings: Postoperative respiratory complications increased the odds of re-hospitalization and outpatient visits by 3·49 times (95% CI: 3·35–3·64) and 1·39 times (95% CI: 1·34–1·45) among surgical patients, respectively. The mean incremental cost associated with postoperative respiratory complications occurring within 30 days of the index admission was 1053·3 USD (95% CI: 940·7–1165·8) per procedure, which was equivalent to 41% of the GDP per capita of Vietnam in 2018. We estimated the national annual incremental cost due to respiratory complications occurring within 30 days after surgery was 13·87 million USD. Pneumonia contributed the greatest part of the annual cost burden of postoperative respiratory complications. Interpretation: The economic burden of postoperative respiratory complications is substantial at both individual and national levels. Postoperative respiratory complications also increase the odds of re-hospitalization and outpatient visits and increase the length of hospital stay among surgical patients. Funding: The authors did not receive any funds for conducting this study

Mục tiêu của nghiên cứu là (i) xác định thời điểm xuống giống và hoạt chất sinh trưởng cho tăng năng suất mè, (ii) xác định thời điểm thu hoạch phù hợp để đạt năng suất và hàm lượng dầu trong hạt mè. Thí nghiệm 1 được bố trí 2 nhân tố: (A) thời điểm gieo sạ (sớm 14 ngày, trùng với nông dân và trễ 14 ngày so với nông dân); (B) sử dụng hoạt chất sinh trưởng (Brassinolide, Canxi-Bo và Selenium). Thí nghiệm 2 được bố trí 2 nhân tố: (A) thời điểm gieo sạ (sớm 14 ngày, trùng với nông dân và trễ 14 ngày so với nông dân), (B) thời điểm thu hoạch (85, 95 và 100% lá vàng). Mỗi nghiệm thức có 3 lần lặp lại. Kết quả cho thấy xuống giống sớm 14 ngày cho số trái trên cây, số hạt trên trái, khối lượng 1.000 hạt và năng suất cao. Phun bổ sung Canxi-Bo giúp tăng số trái trên cây mè tại Lấp Vò. Trong khi phun Brassinolide làm tăng chiều cao cây, số trái trên cây và năng suất mè tại Hồng Ngự. Thu hoạch mè vào thời điểm 95% hoặc 100% số lá chuyển vàng cho năng suất mè cao hơn so với thu hoạch mè vào thời điểm 85% lá vàng. Thu hoạch mè vào thời điểm 100% số lá chuyển vàng cho hàm lượng dầu trong hạt cao.

The effect of austenitizing conditions on the microstructure and mechanical properties of an austempered ductile iron (ADI) with a dual matrix was investigated. Carbon diffusion plays a critical role in the phase transformation of austenitization. In initially pearlitic structures, the carbon diffusion distances involved during austenitization are smaller compared to those in ferritic structures. The study was carried out to examine the influence of temperature and times of the austenitization process on the maximum carbon content in austenite and then its effect on the processing window of ADI with the dual matrix. An alloyed ductile iron (3,6%C; 2,44%Si; 0,36%Mn; 0,9%Ni; 0,61%Cu; 0,11%Cr; 0,036%Mg; 0,015%S và 0,006%P) was fully austenitic at various temperatures 870 °C–930 °C. The minimum hardness reaches the value of 270 HB. An increase in austenitization temperature increases the carbon content dissolved in the austenite, which in turn, decreases the free energy controlling the transformation of austenite to bainite ferrite and high carbon austenite. Raising the austenitization temperature makes the process window shift toward the extending time. The carbon atoms must diffuse out of the ferrite needle with a diffusion distance equal to the ferrite layer thickness. At 360 °C austempered temperature, diffusion coefficient D = 4.60.10 ^–17 (m ^2 /s). With a ferrite needle thickness of 1 μ m = 10 ^–6 m, the diffusion time would be t = 5330 (s).

Abstract Background Ventilator-associated respiratory infection (VARI) is a significant problem in resource-restricted intensive care units (ICUs), but differences in casemix and etiology means VARI in resource-restricted ICUs may be different from that found in resource-rich units. Data from these settings are vital to plan preventative interventions and assess their cost-effectiveness, but few are available. Methods We conducted a prospective observational study in four Vietnamese ICUs to assess the incidence and impact of VARI. Patients ≥ 16 years old and expected to be mechanically ventilated > 48 h were enrolled in the study and followed daily for 28 days following ICU admission. Results Four hundred fifty eligible patients were enrolled over 24 months, and after exclusions, 374 patients’ data were analyzed. A total of 92/374 cases of VARI (21.7/1000 ventilator days) were diagnosed; 37 (9.9%) of these met ventilator-associated pneumonia (VAP) criteria (8.7/1000 ventilator days). Patients with any VARI, VAP, or VARI without VAP experienced increased hospital and ICU stay, ICU cost, and antibiotic use (p

The quantitative analysis of Fern diversity for Hon Giao dwarf forest in Bidoup Nui Ba National Park is necessary to create a solution for conservation and sustainable use of biodiversity resources. The quantitative analysis of biology in order to determine the following in indicies: taxon diversity, Density (D), Frequency (F), Abundance (A), A/F, H (Shannon’s index), Cd (Simpson’S index), SI (Sorensen’s index) was used to quantify the diversity of Fern. The results showed that quantitative support for the generality of positive heterogeneity-richness relationship across heterogeneity components, taxa, spartial scale. The taxon diversity at the study sites were recorded with 25 species, 22 genus and 4 orders of Fern. The species distributed and varied greatly in spatial scale. Fern diversity was the highest at sites with low altitudes (1600-1700 m a.s.l.) and the lowest at site with high altitudes (≥ 1800m a.s.l.). Otherwise, based on the sites were they grew, Fern diversity was also the higest with high soil moisture, fertility.

Human urine is known as the excreta with a high concentration of nitrogen and phosphorus, causing eutrophication in water bodies. In this study, human urine was used to feed microalgae (Chlorella vulgaris) in a membrane photobioreactor (MPBR) at various microalgae retention times (MRTs) and hydraulic retention time (HRT) of 2 days to evaluate its biomass production. The results indicate that MPBR was operated under MRT of 2 to 5 days and HRT of 2 days, which performed the optimum condition with biomass productivity from 146.43±8.52 to 151.93±15.05 mg.l-1.day. Moreover, the MPBR using the urine as a nutrient source demonstrated the high performance in biomass production and strong growth of microalgae.

Thí nghiệm được thực hiện ngoài trời, bố trí khối ngẫu nhiên hoàn toàn với 8 nghiệm thức (NT): NT1:Xếp mô+ meo 40 g, NT2: Xếp mô + meo 80 g, NT3:Xếp mô + meo 120 g, NT4:Xếp mô + meo 160 g, NT5: Đóng khuôn + meo 40 g, NT6: Đóng khuôn + meo 80 g, NT7: Đóng khuôn + meo 120 g, NT8: Đóng khuôn + meo 160g và 5 lần lặp lại. Kết quả thí nghiệm cho thấy nhiệt độ và pH mô nấm nằm trong khoảng cho phép nấm rơm phát triển. Nhiệt độ mô nấm làm giảm tổng trọng lượng quả thể nấm. Biên độ chênh lệch nhiệt độ mô nấm ở cách chất xếp mô so với đóng khuôn là 2,20C. Chiều dài, chiều rộng và tỷ lệ dài/rộng của 30 quả thể xuất hiện đầu tiên đều không bị ảnh hưởng của cách chất xếp mô hay đóng khuôn. Tổng trọng lượng quả thể (2,86 kg/1,5 m dòng) và tổng số lượng quả thể (347,6 quả/1,5 m dòng) cao nhất ở phương pháp xếp mô kết hợp lượng meo 160 g/1,5 m dòng.

Nghiên cứu sự thay đổi thành phần tinh bột, amylose, đường khử (RS) và hoạt tính α-amylase (AA) tại các điều kiện ngâm khác nhau như pH 3÷6; pH tối thích có dịch cám (RB) 3÷7% hay acid glutamic (GA) 0,2÷0,6% cũng như nảy mầm ở 37o­C, yếm khí trong 20÷28 giờ đã được thực hiện. Kết quả cho thấy, nhiệt độ 50oC và pH=5 là điều kiện thích hợp nhất của AA từ hai giống IR50404 và MBĐ. pH thích hợp của MBĐ khi ngâm trong 6 giờ là 4, IR50404 là 3. AA ở MBĐ cao nhất là 60,42 (UI/g) và RS cao nhất là 37,31 (mg/g); AA ở IR50404 cao nhất là 58,38 (UI/g) và RS cao nhất là 37,74 (mg/g). Ở cả 2 giống MBĐ và IR50404, AA khi ngâm ở pH tối ưu có bổ sung RB có xu hướng giảm sau đó tăng dần và đạt tương đương với hoạt tính ban đầu khi không bổ sung. Ở cả 2 giống MBĐ và IR50404, AA khi ngâm ở pH tối ưu có GA có xu hướng giảm dần khi tăng GA và khác biệt so với các nồng độ còn lại ở 0,6%. Như vậy, mỗi giống lúa có pH ngâm thích hợp khác nhau, có thể bổ sung RB 7%, bổ sung GA 0,4% mà AA là không có sự khác biệt ở 2 giống.

In this report, overview of the new installed Pelletron 5SDH-2 accelerator at Hanoi University of Science, Vietnam and possibilities for performing astrophysics-related nuclear reactions based on this accelerator will be described. In addition to that, some preliminary simulation results for designing and optimizing the experimental set-up in studying reactions 10B(α, p)13C with projectile energies in the Gamow-window will be shown.

We performed a retrospective case-series study of patients with influenza A (H5N1) admitted to the National Institute of Infectious and Tropical Diseases in Hanoi, Vietnam, from January 2004 through July 2005 with symptoms of acute respiratory tract infection, a history of high-risk exposure or chest radiographic findings such as pneumonia, and positive findings for A/H5 viral RNA by reverse transcription–PCR. We investigated data from 29 patients (mean age 35.1 years) of whom 7 (24.1%) had died. Mortality rates were 20% (5/25) and 50% (2/4) among patients treated with or without oseltamivir (p = 0.24), respectively, and were 33.3% (5/15) and 14.2% (2/14) among patients treated with and without methylprednisolone (p = 0.39), respectively. After exact logistic regression analysis was adjusted for variation in severity, no significant effectiveness for survival was observed among patients treated with oseltamivir or methylprednisolone.

Nghiên cứu này nhằm tìm ra giải pháp nâng cao vai trò phụ nữ trong tham gia tập huấn khoa học kỹ thuật lĩnh vực sản xuất lúa ở thành phố Cần Thơ, cụ thể là địa bàn quận Ô Môn và huyện Thới Lai. Nghiên cứu được thực hiện bằng cách phỏng vấn 120 nông dân trong và ngoài lớp tập huấn theo số liệu tách biệt giới. Kết quả phân tích cho thấy các yếu tố như người phụ nữ trình độ học vấn thấp, có ít năm kinh nghiệm sản xuất, bận rộn chăm sóc con cái và mất nhiều thời gian vào các hoạt động kinh tế khác thì thường ít được tham gia tập huấn. Nhằm nâng cao cơ hội tập huấn cho phụ nữ, các đoàn thể địa phương cần tăng cường liên kết tuyên truyền giới trong cộng đồng, các cơ quan khuyến nông cần gắn hiệu quả kinh tế với tập huấn, người phụ nữ cần chủ động nâng cao kiến thức và sự tự tin của bản thân là các giải pháp chính yếu đã được đề ra.

Phân tích phẩm chất gạo của tập đoàn 835 giống lúa MTL đang bảo quản tại Ngân hàng Gen, Viện Nghiên cứu Phát triển Đồng bằng sông Cửu Long, Trường Đại học Cần Thơ theo các tiêu chí phân cấp của IRRI,1996. Kết quả cho thấy đây là nguồn gen có biến động lớn về các đặc tính phẩm chất gạo, đặc biệt về độ bạc bụng và hàm lượng amylose. Cả hai nhóm lúa tẻ và lúa nếp cho thấy hàm lượng amylose tương quan thuận với chiều dài hạt gạo. Nhóm lúa tẻ có đặc tính mùi thơm tương quan nghịch với trọng lượng hạt, chiều dài hạt, bạc bụng và hàm lượng amylose. Các giống lúa có hạt gạo dài hơn 7 mm và không bạc bụng là MTL199, MTL124, MTL309, MTL331, MTL422, MTL512, MTL513. Những đặc tính quý như gạo rất thơm và hàm lượng amylose thấp hơn 20% có ở các giống lúa MTL233, MTL392, MTL372.

BACKGROUND:The pathogenesis of acute measles encephalitis (AME) is poorly understood. Treatment with immune-modulators is based on theories that post-infectious autoimmune responses cause demyelination. The clinical course and immunological parameters of AME were examined during an outbreak in Vietnam. METHODS AND FINDINGS:Fifteen measles IgM-positive patients with confusion or Glasgow Coma Scale (GCS) score below 13, and thirteen with uncomplicated measles were enrolled from 2008-2010. Standardized clinical exams were performed and blood collected for lymphocyte and measles- and auto-antibody analysis. The median age of AME patients was 21 years, similar to controls. Eleven reported receiving measles vaccination when aged one year. Confusion developed a median of 4 days after rash. Six patients had GCS

In the absence of a parenteral drug, oral oseltamivir is currently recommended by the WHO for treating H5N1 influenza. Whether oseltamivir absorption is adequate in severe influenza is unknown. We measured the steady state, plasma concentrations of nasogastrically administered oseltamivir 150 mg bid and its active metabolite, oseltamivir carboxylate (OC), in three, mechanically ventilated patients with severe H5N1 (male, 30 yrs; pregnant female, 22 yrs) and severe H3N2 (female, 76 yrs). Treatments were started 6, 7 and 8 days after illness onset, respectively. Both females were sampled while on continuous venovenous haemofiltration. Admission and follow up specimens (trachea, nose, throat, rectum, blood) were tested for RNA viral load by reverse transcriptase PCR. In vitro virus susceptibility to OC was measured by a neuraminidase inhibition assay. Admission creatinine clearances were 66 (male, H5N1), 82 (female, H5N1) and 6 (H3N2) ml/min. Corresponding AUC(0-12) values (5932, 10,951 and 34,670 ng.h/ml) and trough OC concentrations (376, 575 and 2730 ng/ml) were higher than previously reported in healthy volunteers; the latter exceeded 545 to 3956 fold the H5N1 IC(50) (0.69 ng/ml) isolated from the H5N1 infected female. Two patients with follow-up respiratory specimens cleared their viruses after 5 (H5N1 male) and 5 (H3N2 female) days of oseltamivir. Both female patients died of respiratory failure; the male survived. 150 mg bid of oseltamivir was well absorbed and converted extensively to OC. Virus was cleared in two patients but two patients died, suggesting viral efficacy but poor clinical efficacy.

PROBLEM: Streptococcus suis is a common cause of adult bacterial meningitis in Viet Nam, and possibly other parts of Asia, yet this disabling infection has been largely neglected. Prevention, diagnosis and treatment are relatively straightforward and affordable but, in early 2007, no national diagnostic, case management or prevention guidelines existed in Viet Nam. APPROACH: Enhanced detection of S. suis infections was established in 2007 as part of a collaborative research programme between the National Hospital for Tropical Diseases, a key national hospital with very close links to the Ministry of Health, and a research group affiliated with Oxford University based in Viet Nam. The results were reported directly to policy-makers at the Ministry of Health. LOCAL SETTING: Viet Nam is a low-income country with a health-care system that has seen considerable improvements and increased autonomy. However, parts of the system remain fairly centralized the Ministry of Health. RELEVANT CHANGES: Following the improved detection and reporting of S. suis cases, the Ministry of Health issued guidance to all hospitals in Viet Nam on the clinical and laboratory diagnosis, treatment and prevention of S. suis. A public health laboratory diagnostic service was established at the National Institute of Hygiene and Epidemiology and training courses were conducted for clinicians and microbiologists. Ministry of Health guidance on surveillance and control of communicable diseases was updated to include a section on S. suis. LESSONS LEARNT: Research collaborations can efficiently inform and influence national responses if they are well positioned to reach policy-makers.

Objective: We conducted a descriptive analysis of multi-drug resistant tuberculosis (MDR-TB) in Vietnam's two largest cities, Hanoi and Ho Chi Minh city., Methods: All patients with rifampicin resistant tuberculosis were recruited from Hanoi and surrounding provinces between 2020 and 2022. Additional patients were recruited from Ho Chi Minh city over the same time period. Demographic data were recorded from all patients, and samples collected, cultured, whole genome sequenced and analysed for drug resistance mutations. Genomic susceptibility predictions were made on the basis of the World Health Organization's catalogue of mutations in Mycobacterium tuberculosis associated with drug resistance, version 2. Comparisons were made against phenotypic drug susceptibility test results where these were available. Multivariable logistic regression was used to assess risk factors for previous episodes of tuberculosis., Results: 233/ 265 sequenced isolates were of sufficient quality for analysis, 146 (63 %) from Ho Chi Minh City and 87 (37 %) from Hanoi. 198 (85 %) were lineage 2, 20 (9 %) were lineage 4, and 15 (6 %) were lineage 1. 17/211 (8 %) for whom HIV status was known were infected, and 109/214 (51 %) patients had had a previous episode of tuberculosis. The main risk factor for a previous episode was HIV infection (odds ratio 5.1 (95 % confidence interval 1.3-20.0); p = 0.021). Sensitivity for predicting first-line drug resistance from whole genome sequencing data was over 90 %, with the exception of pyrazinamide (85 %). For moxifloxacin and amikacin it was 50 % or less. Among rifampicin-resistant isolates, prevalence of resistance to each non-first-line drug was < 20 %., Conclusions: Drug resistance among most MDR-TB strains in Vietnam's two largest cities is confined largely to first-line drugs. Living with HIV is the main risk factor among patients with MDR-TB for having had a previous episode of tuberculosis., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)