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Carbon dioxide is considered as a primary reason for global climate change, thus CO2 needs to be urgently reduced. Catalytic conversion of CO2 into chemical fuels is one of the most crucial technologies that can address both global warming and the depletion of fossil fuels. Rhenium tricarbonyl complex [Re(bpy)(CO)3Cl] (bpy: 2,2’ bipyridine) possesses a great potential of capturing and highly selective converting CO2 to carbon monoxide. In the current study, we synthesized and characterized the structure of [Re(bpy)(CO)3Cl] by 1H NMR, ESI-MS, FITR, and PL spectroscopy. The electrochemical properties and the electrochemical CO2 reduction of [Re(bpy)(CO)3Cl] in the absence and presence of an electron donor source were carried out using cyclic voltammetric measurements. The cyclic voltammogram of [Re(bpy)(CO)3Cl] in N2-saturated DMF solution displayed one irreversible reduction wave at -1.33 V. [Re(bpy)(CO)3Cl] expressed its electrocatalytic behavior in CO2 atmosphere by the enhancement of the cathodic current density. The current increased approximately twofold in CO2-saturated DMF solution (from 0.15 to 0.32 mA/cm2) and more enhancement when adding TEOA solvent. With the presence of an electron donor, the CO2 reduction efficiency of [Re(bpy)(CO)3Cl] was improved and represented by an approximately fourfold increase in cathodic current from 0.32 to 1.12 mA/cm2. One-electron reduced species of [Re(bpy)(CO)3Cl] observed at 1.33 V in N2 and CO2-saturated electrolytes contributed to the reaction with CO2.

This is a case report of an elderly male patient who was diagnosed with meningococcal pneumonia resulting in respiratory failure. The patient had pre-existing conditions of chronic obstructive pulmonary disease (COPD) and prostate cancer. Upon admission, the patient exhibited symptoms such as a purulent cough producing sputum, dyspnea, decreased oxygen saturation, and chest X-ray images that were consistent with pneumonia. The bacteria responsible for the infection was identified as Neisseria meningitidis through bacterial culture, which was found to be antibiotic-resistant. The patient did not show any signs of septicemia or meningitis. Treatment was initiated with an appropriate antibiotic regimen, and the patient was discharged after demonstrating improvement over 10 days. Close contacts of the patient were given prophylactic antibiotics, and no secondary infections were recorded. In this article, we will present a detailed case report, and provide an overview of the epidemiology of meningococcal infections in Vietnam, as well as summarizing the clinical characteristics of meningococcal pneumonia cases globally.

This study presents a flipped classroom approach tailored to provide dynamic instructional learning of one translation module in Vietnam. The model took consideration of relevant factors of Activity theory (instruments, rules, community and division of labour) to (1) investigate how it could re-orientate learners’ translation habits, and (2) find out the mitigated challenges encountered by Vietnamese learners. 39 junior students at a public university in Vietnam participated in the study. The research implemented a case study design, using semi-structured interviews to examine in depth the benefits of this flipped setting and its actual challenges. The collected findings revealed that this approach could not only bridge the gaps in the relevant literature of flipped learning, but also could improve learners’ habits to use appropriate translation strategies. Finally, challenges faced by learners during the implementation were minimised, thanks to the systematic structure of the flipped classroom procedure and Activity theory.

Neem (Azadirachta indica A. Juss.) oil has been widely used in pharmaceuticals and cosmetics. The oil was extracted by the hydraulic press at the pilot scale. The effect of various critical factors such as the morphology of material, moisture of the neem seed, applied pressure, a number of presses turn, pressing time on the oil yield was considered. It was found that the oil yield increased with increasing applied pressure and pressing time. The moisture content of the neem seed kernel has a great influence on the oil yield, the higher the moisture content, the harder it is to recover the oil. The highest oil yield of 378mL/kg dry seed kernel was obtained at 190 MPa, 4% moisture content for 10 minutes of pressing per turn, and 3 turns of pressing. The main ingredients in neem kernel oil were oleic acid (45.9%), stearic acid (18%), palmitic acid (16.9%), and linoleic acid (15.65%). The results obtained can be used in the production of Neem oil at an industrial scale.

Mục tiêu: Đánh giá hiệu quả và tính an toàn của khâu cổ tử cung ngả bụng trước thụ thai trong dự phòng sinh non. Đối tượng và Phương pháp nghiên cứu: Đây là một báo cáo hồi cứu loạt ca. Tất cả những phụ nữ được thực hiện khâu cổ tử cung ngả bụng trước thụ thai tại bệnh viện Mỹ Đức trong thời gian từ tháng 01/2015 đến tháng 01/2020 được nhận vào nghiên cứu. Chỉ định khâu cổ tử cung ngả bụng tại bệnh viện là những phụ nữ có tiền căn sẩy thai ở tam cá nguyệt thứ 2 hoặc sinh non đã khâu vòng cổ tử cung qua ngả âm đạo hoặc sinh non có bất thường cấu trúc giải phẫu ở cổ tử cung. Sau khâu cổ tử cung, bệnh nhân được thụ thai bằng cách tự nhiên hoặc thông qua kỹ thuật hỗ trợ sinh sản. Kết cục chính là tỷ lệ sinh từ 34 tuần trở lên. Tỷ lệ trẻ sinh sống, tuổi thai trung bình khi sinh, kết cục sơ sinh, thời gian phẫu thuật, thời gian nằm viện và các biến chứng sau phẫu thuật là các kết cục phụ của nghiên cứu. Kết quả: Từ tháng 1/2015 đến tháng 1/2020, có 19 phụ nữ đủ tiêu chuẩn thu nhận, trong đó có 5 phụ nữ đã sinh và 4 phụ nữ đang mang thai. 3/5 (60%) trường hợp sinh từ 34 tuần trở lên. Thời gian khâu cổ tử cung ngả bụng trung bình là 43,3 phút, thời gian nằm viện sau khâu trung bình là 4,1 ngày. Tỷ lệ sinh sống là 5/5 (100%) với tuổi thai trung bình là 33,9 tuần. Kết luận: Khâu cổ tử cung ngả bụng trước thụ thai có thể là một chọn lựa trong việc dự phòng sinh non cho các trường hợp có tiền căn sinh non hoặc tiền căn sẩy thai ở tam cá nguyệt thứ 2 dù đã được khâu cổ tử cung ngả âm đạo trước đó, và / hoặc bất thường giải phẫu ở cổ tử cung.

ADC (apparent coefficient diffusion) value has been known to predict hemorrhage transformation (HT) after thrombolysis and recently, after mechanical thrombectomy (MT). We aimed to evaluate that utility separately in basal ganglia and superficial territory. We used HT occurrence with or without NIHSS change as primary outcome measures.This single-center retrospective study included consecutive stroke patients receiving MT for internal carotid artery (ICA) or middle cerebral artery (M1 or M2) occlusion. In patient with or without HT, using the Heidelberg Bleeding Classification, on follow-up CT scan at 24-48 h, we assessed the ADC value separately in basal ganglia and superficial territory on MRI before MT to search for the correlation. Multivariable analysis was performed using variables with significant differences between the HT group and non-HT group.One hundred seventeen patients were included in the final analysis. HT distribution was as follows: 9 patients (7.69%) HI1 or 2; 14 patients (11.97%) PH1; 21 patients (17.95%) PH2; 29 patients (24.79%) subarachnoid hemorrhage; and 21 patients (17.95%) symptomatic intracranial hemorrhage (sICH). Mean ADC minimal value in basal ganglia in the HT group was significantly lower than in the non-HT group (377.6 × 10ADC value in basal ganglia, unlike brain superficial territory, are correlated to HT risk after MT.

Raw foods such as fish and meat sold at local markets are easily pathogenically infected because retailers do not keep them in proper food preservation equipment. In addition, food packaging using single-use plastic grocery bags is a burden for waste management and aggravates the “white pollution”. In this research, we created biodegradable bacterial cellulose membrane (BCm) loaded with raw bacteriocins that were collected from isolated lactic acid bacteria (LAB) and test their ability to preserveraw fish and meat. The 2mm thick and 94% wet BC membrane was obtained from the surface fermentation of Acetobacterxylinum in the medium containing 50% of coconut water and 15% sucrose after 03 days. The isolated LAB from sour cabbage, kimchi and yogurt were microscopically observed, biochemically characterized and species identified by mass spectrometry. The raw bacteriocin from Lactobacillus plantarum showing the most antimicrobial capability among the isolates could inhibit the growth of 3 tested strains of Escherichia coli, Staphylococcus aureus and Bacillus subtilis at the antimicrobial activity of 100 AU/ml by agar-well diffusion method. BCm treated with the bacteriocins of 100 AU/ml in 45 minutes was proved to be able to well preserve fish for 24 hours and pork for 18 hours at ambient temperatures, following Vietnam Standard for catfish fillet (TCVN 8338:2010) and for meat (TCVN 7046:2009).

Background Perception of harm plays an important role in predicting intention to quit—an integral part of the cessation process. Perception on harm from bamboo waterpipe tobacco was unknown, even the predominant of this type of tobacco use. This study investigated the effects of perceived harm from cigarette and bamboo waterpipe tobacco on intention to quit among adult male Vietnamese tobacco users. Methods From the nationally-representative 2015 Global Adult Tobacco Survey, we included 1,351 adult males (≥ 18 years old) who used cigarettes, bamboo waterpipes, or both. Demographic characteristics, tobacco use behaviors, perceived harm from tobacco use, and regulation/policy exposure were measured. Effects of perceived harm from cigarette and bamboo waterpipe tobacco on intention to quit were assessed by logistic regression. Results Intention to quit prevalence was 59.0%, 55.0%, and 58.4% for cigarette, waterpipe, and dual users, respectively. Tobacco users who perceived that “using cigarettes and/or waterpipe could cause severe illness” and “waterpipe use is less harmful than cigarette smoking”, had tobacco use bans at home, or were exposed to anti-smoking campaigns or encouragement to quit information were more likely to intend to quit. When analyzed by tobacco users, intention to quit was more likely for those users who perceived their tobacco product as more harmful than the other product type, although statistical significance was only observed for cigarette users. Conclusions Misperceptions regarding harm from tobacco use could negatively affect intention to quit. Dissemination of accurate information on the risks from all forms of tobacco use and enforcement of tobacco control policies are important for encouraging intention to quit.

Ultrasound-assisted air-drying is considered a useful method to reduce drying time and ensure the quality of some agricultural food products. In this study, an effective design method of an ultrasonic transducer (UT) which is in a form of a circular stepped-plate was developed by using particle swarm optimization (PSO) algorithm and finite element analysis (FEA). Based on calculated and analyzed results, dimensions of the UT were found out and its prototypes were fabricated. The measured resonance frequency of the prototype is 19927 Hz compared to calculations getting error of 50 Hz (0.25%). In addition, to evaluate effects of ultrasound on a drying process, the UT is integrated into heat-pump drying machine for drying foods. The experiments were carried out on Codonopsis javanica using heat-pump drying method at air temperature 45 ± 0.5 °C, air humidity 18–20%, air velocity 0.5 ± 0.1 m/s with and without ultrasonic intensity whilst keeping all other conditions and parameters constant. The results showed that the total drying time was reduced in the range of 25% to 42% depending on ultrasonic intensity, compared to heat-pump drying without ultrasonic intensity.

Background The COVID-19 pandemic has hit all corners of the world, challenging governments to act promptly in controlling the spread of the pandemic. Due to limited resources and inferior technological capacities, developing countries including Vietnam have faced many challenges in combating the pandemic. Since the first cases were detected on 23 January 2020, Vietnam has undergone a 3-month fierce battle to control the outbreak with stringent measures from the government to mitigate the adverse impacts. In this study, we aim to give insights into the Vietnamese government's progress during the first three months of the outbreak. Additionally, we relatively compare Vietnam's response with that of other Southeast Asia countries to deliver a clear and comprehensive view on disease control strategies. Methods The data on the number of COVID-19 confirmed and recovered cases in Vietnam was obtained from the Dashboard for COVID-19 statistics of the Ministry of Health (https://ncov.vncdc.gov.vn/). The review on Vietnam's country-level responses was conducted by searching for relevant government documents issued on the online database 'Vietnam Laws Repository' (https://thuvienphapluat.vn/en/index.aspx), with the grey literature on Google and relevant official websites. A stringency index of government policies and the countries' respective numbers of confirmed cases of nine Southeast Asian countries were adapted from the Oxford COVID-19 Government Response Tracker (https://www.bsg.ox.ac.uk/research/research-projects/coronavirus-government-response-tracker). All data was updated as of 24 April 2020. Results Preliminary positive results have been achieved given that the nation confirmed no new community-transmitted cases since 16 April and zero COVID-19 - related deaths throughout the 3-month pandemic period. To date, the pandemic has been successfully controlled thanks to the Vietnamese government's prompt, proactive and decisive responses including mobilization of the health care systems, security forces, economic policies, along with a creative and effective communication campaign corresponding with crucial milestones of the epidemic's progression. Conclusions Vietnam could be one of the role models in pandemic control for low-resource settings. As the pandemic is still ongoing in an unpredictable trajectory, disease control measures should continue to be put in place in the foreseeable short term.

Phytochemical study on the EtOAc-soluble extract of the leaves of

In several last decades, Single Point Incremental Forming named as SPIF, a branch of Incremental Sheet Forming (ISF), is an advanced flexible manufacturing process to produce complex 3D sheet products especially for unique models such as personal cranium, cheek-bone,…applied in surgery. Presently, the SPIF technology has been continuously studied, applied and perfected for metal sheet manufacturing, especially Titanium and its alloys in some industrial sectors like aerospace, chemical engineering, and medical surgery. However, the formability of Titanium alloys is limited at room temperature that causes so many failures and tears of sheet workpiece when forming. This paper recommends a measure of increasing the plasticity of the formed metal sheet by heating. This paper studies on the effect of the control of temperature to increase the plasticity of the sheet workpiece. The accuracy of dimensions of the products under the effect of springback phenomenon in forming process at normal and high temperature of workpiece is also studied to show the effect of hot SPIF. The design of experiment (DOE) is also mentioned in this paper to select a set of suitable input parameters for the empirical process.

Phytochemical study on the EtOAc-soluble extract of the leaves of Mimosa pigra led to the isolation of a new furanochromone, 6,8-dihydroxy-2-methyl-9H-furo[3,2-b]chromen-9-one (1), along with four known compounds (2–5). Their structures were elucidated based on the basis of the spectral interpretation. The plausible biosynthesis pathway for the formation of the new furanochromone was proposed. At a concentration of 100 µM, compound 1 showed no cytotoxicity against human MCF-7 breast cancer cell with a cell viability >50%.

Ultrasound-assisted air-drying is considered a useful method to reduce drying time and ensure some agricultural food products' quality. In this study, a practical design method of an Ultrasonic Transducer (UT), which is in the form of a circular stepped-plate, was developed by using Particle Swarm Optimization (PSO) algorithm and Finite Element Analysis (FEA). The numerical calculation is carried out for two different geometric dimensions of the stepped-plate. Based on the obtained results, the smaller UT dimensions were chosen, and its prototypes were fabricated. The prototype's measured resonance frequency is 19.927 kHz compared to calculations getting an error of 0.073 kHz (0.37%). Also, to evaluate the effects of ultrasound on a drying process, the UT is integrated into a heat-pump drying machine for drying foods. The experiments were carried out on Codonopsis javanica using heat-pump drying method at air temperature 45 ± 0.5 °C, air humidity 18-20 %, air velocity 0.5 ± 0.1 m/s with and without ultrasonic intensity while keeping all other conditions and parameters constant. The results showed that the total drying time was reduced in the range of 25% to 42% depending on ultrasonic intensity, compared to heat-pump drying without ultrasonic intensity. The color of the dried products is also considered to testify the quality of the product when using UT in drying processes. The obtained results prove the effectiveness of the proposed approach in design of the UT for food dehydration.

Zinc oxide nanorods (ZnO NRs) were modified by decorating with silver (Ag) nanoparticles to enhance visible absorption. The morphology, structure and optical properties of the modified ZnO NRs were investigated by scanning electron microscopy, x-ray diffraction and UV–vis absorption spectroscopy. Photodetectors (PDs) based on the modified ZnO NRs successfully detected visible radiation. The result showed high performance of the visible sensor (λ = 400 nm) with a maximum responsivity of 46 mA W−1. The photoconductive gain of Ag/ZnO NR-based PDs was 5.8 times higher than that of pure ZnO NR ones. With their enhanced visible absorption, the multi-modified ZnO NRs are suitable for practical applications, especially in optoelectronic devices operating in the visible region.

Background: Randomized controlled trials for calcium antagonists therapy in patients with acute ischemic stroke have failed to show a benefit as a stand-alone therapy, due largely to the reduction of blood pressure, especially in the absence of early recanalization. Since mechanical thrombectomy (MT) has led to high successful recanalization rates, the effect of nimodipin as an adjuvant therapy during MT has not been evaluated. Materials and Methods: We retrospectively reviewed all consecutive cases of MT for which Nimodipin was used as an adjuvant therapy after at least one pass of any device. Clinical and angiographic characteristics, as well as immediate vessel caliber modifications, reperfusion status and early neurological improvement were collected between January 2016 and December 2017. Results: Procedural intra-arterial nimodipin infusion was administered in 10.3 % (58/559; 95%CI 7.8-12.8 %) of patients, after at least one pass of MT device. In 52/58 patients, < 3 manoeuvers of MT were performed. Angiographic vasospasm was identified on the carotid artery in 17/58 (29.3%) cases, on the middle cerebral artery in 35/58 (60.4%) cases and in vertebro-basilar artery in 6/58 (10.3%) cases. The vasospasm was responsible for an immediate reocclusion in 12% of the patients. Angiographic effect of nimodipin with the restauration of a normal vessel caliber and the improvement of the reperfusion without supplementary maneuver was observed in 77.5% % of the cases. Successful recanalization TICI 2b/3 was reached in 81% patients. Significant drop of blood pressure (BP) with need for additional vasopressive drugs was observed in 6 cases. Symptomatic hemorrhage occurred in 3 patients (5%). Concomitant fibrinolytic therapy did not influence the rate of intracranial hemorrhage rate after procedural nimodipin infusion (p=0.912). Early neurological improvement was reached in 46% and was not associated with a high initial systolic and diastolic BP at the admission (p=0.89) or with the modality of anesthesia (p =0.76). Conclusion: Nimodipin can be an efficient and safe adjuvant therapy in the setting of vasospasm due to MT, by normalizing the caliber of the recanalized artery and then, improving the reperfusion status without supplementary maneuver of MT.