47 research outputs found

    Isothiouronium Organocatalysts Through Hydrogen Bonding

    Get PDF
    The field of small‐molecule organocatalysis via noncovalent interactions has attracted the attention of an increasing number of research groups from the academic as well as industrial sectors. Isothiouronium salts have been explored quite recently as a new class of hydrogen‐bonding subunit for the purpose of molecular recognition of anions in supramolecular chemistry. The chemical modification of isothiouroniums is readily varied using synthetic methods to make several types of functional molecular systems. This chapter, for the first time, describes the research on hydrogen‐bonding isothiouronium organocatalysts considering their designed concepts and synthetic applications in both nonstereoselective and stereoselective reactions

    Tetra­butyl­ammonium N-benzoyl-6-nitro-1,3-benzothia­zol-2-aminide

    Get PDF
    In the title salt, C16H36N+·C14H8N3O3S−, the torsion angles within the cation reveal that one butyl group displays an anti conformation and the other three butyl groups show gauche conformations. The anion is almost planar, with a largest deviation of 0.166 (6) Å from the least-squares plane (r.m.s. deviation of fitted atoms = 0.052 Å). In the crystal structure, the component ions inter­act by means of weak inter­molecular C—H⋯O hydrogen bonds

    Factors affecting the creativity of high school students

    Get PDF
    Creativity is a vital personality quality of each individual. Each person has their potential for creativity, and it can be nurtured and developed in an appropriate and safe environment. The purpose of the study was to find out which factors from schools and students themselves affect creativity as well as the association between creativity and age, gender and giftedness of students, which then a basis to adjust and establish appropriate methods from schools, families, and students themselves to develop elements and their creativity. The study was conducted on 108 high school students in three grades from giftedness and non-giftedness schools. The data was collected through a survey method using a self-constructed questionnaire and drawing creativity test TCT-DP to determine students' creativity levels and personal information. The study's finding, which uses mathematical methods and one-way analysis of variance, reveals that factors affecting elements and creativity level are objective factors including education environment from school; behavior of teachers, and subjective factors including interests, perspectives, and thoughts of students. It was also found that there were no significant differences in the components of creativity and creativity among students in different grades, gender, and groups of giftedness schools

    ẢNH HƯỞNG CỦA MỘT SỐ YẾU TỐ ĐẾN QUÁ TRÌNH CHẾ TẠO NANO BẠC SỬ DỤNG DỊCH CHIẾT LÁ VỐI LÀM TÁC NHÂN KHỬ

    Get PDF
    In this study, we use the aqueous extract of Robusta plant leaves as a reducing agent and alginate as a surfactant to synthesize silver nanoparticles from silver nitrate (AgNO3). The influence of extraction time and the solid-liquid ratio, the concentration of AgNO3, the volume ratio between silver nitrate solution and the extract of Robusta leaves, and the reaction time on the synthesis were investigated. The optimal conditions are as follows: 15 g of leaves/200 mL, silver nitrate concentration 4 mM, Vextract/VAgNO3 4:100, 1% sodium alginate solution, and reaction time 45 minutes. The obtained solution of silver nanoparticles has a yellow-brown color. The TEM, XRD, and FT-IR measurements of the samples show that the silver nanoparticles have been successfully synthesized. The particles are spherical with an even size and 19.0-26.6 nm in diameter.Trong nghiên cứu này, chúng tôi trình bày phương pháp điều chế dung dịch nano bạc (Ag) từ bạc nitrate (AgNO3) sử dụng dịch chiết lá vối làm tác nhân khử và alginate là chất hoạt động bề mặt. Chúng tôi khảo sát ảnh hưởng của nồng độ AgNO3, tỷ lệ thể tích giữa AgNO3 và dịch chiết lá vối và thời gian phản ứng đến quá trình tạo nano Ag. Điều kiện tối ưu để tổng hợp nano Ag sử dụng dịch chiết lá vối gồm nồng độ AgNO3 4 mM, tỷ lệ thể tích Vdịch chiết /VAgNO3 = 4:100, nồng độ alginate 1%, thời gian phản ứng 45 phút tại nhiệt độ phòng. Dung dịch nano Ag thu được có màu vàng nâu đồng nhất. Kết quả đo TEM, SEM, XRD và FT-IR của các mẫu cho thấy nano Ag đã được tổng hợp thành công; hạt nano có dạng hình cầu, cấu trúc đồng đều với kích thước hạt khoảng 19,0–26,6 nm

    Research to support and inform the development, implementation and/or evaluation of tobacco control policies in relation to the framework convention on tobacco control in low and middle-income countries

    Get PDF
    In order to enforce policies on tobacco control in Vietnam, reliable information on health and socio-economic hazards associated with tobacco farming is needed. The study investigates the harmful impact of tobacco cultivation and processing on health of tobacco farmers in a rural community in northern Vietnam. Objectives included estimation of health care costs as well as health beliefs related to tobacco cultivation and processing. The health of those who cultivate the crop is constantly put in peril. The study confirms that tobacco farming does not bring prosperity to the farmers while causing them a lot of health problems, especially among women

    Antibiotic use and prescription and its effects on Enterobacteriaceae in the gut in children with mild respiratory infections in Ho Chi Minh City, Vietnam. A prospective observational outpatient study.

    Get PDF
    BACKGROUND AND OBJECTIVES: Treatment guidelines do not recommend antibiotic use for acute respiratory infections (ARI), except for streptococcal pharyngitis/tonsillitis and pneumonia. However, antibiotics are prescribed frequently for children with ARI, often in absence of evidence for bacterial infection. The objectives of this study were 1) to assess the appropriateness of antibiotic prescriptions for mild ARI in paediatric outpatients in relation to available guidelines and detected pathogens, 2) to assess antibiotic use on presentation using questionnaires and detection in urine 3) to assess the carriage rates and proportions of resistant intestinal Enterobacteriaceae before, during and after consultation. MATERIALS AND METHODS: Patients were prospectively enrolled in Children's Hospital 1, Ho Chi Minh City, Vietnam and diagnoses, prescribed therapy and outcome were recorded on first visit and on follow-up after 7 days. Respiratory bacterial and viral pathogens were detected using molecular assays. Antibiotic use before presentation was assessed using questionnaires and urine HPLC. The impact of antibiotic usage on intestinal Enterobacteriaceae was assessed with semi-quantitative culture on agar with and without antibiotics on presentation and after 7 and 28 days. RESULTS: A total of 563 patients were enrolled between February 2009 and February 2010. Antibiotics were prescribed for all except 2 of 563 patients. The majority were 2nd and 3rd generation oral cephalosporins and amoxicillin with or without clavulanic acid. Respiratory viruses were detected in respiratory specimens of 72.5% of patients. Antibiotic use was considered inappropriate in 90.1% and 67.5%, based on guidelines and detected pathogens, respectively. On presentation parents reported antibiotic use for 22% of patients, 41% of parents did not know and 37% denied antibiotic use. Among these three groups, six commonly used antibiotics were detected with HPLC in patients' urine in 49%, 40% and 14%, respectively. Temporary selection of 3rd generation cephalosporin resistant intestinal Enterobacteriaceae during antibiotic use was observed, with co-selection of resistance to aminoglycosides and fluoroquinolones. CONCLUSIONS: We report overuse and overprescription of antibiotics for uncomplicated ARI with selection of resistant intestinal Enterobacteriaceae, posing a risk for community transmission and persistence in a setting of a highly granular healthcare system and unrestricted access to antibiotics through private pharmacies. REGISTRATION: This study was registered at the International Standard Randomised Controlled Trials Number registry under number ISRCTN32862422: http://www.isrctn.com/ISRCTN32862422

    Targeted next-generation sequencing on hirschsprung disease: A pilot study exploits DNA pooling

    Get PDF
    To adopt an efficient approach of identifying rare variants possibly related to Hirschsprung disease (HSCR), a pilot study was set up to evaluate the performance of a newly designed protocol for next generation targeted resquencing. In total, 20 Chinese HSCR patients and 20 Chinese sex-matched individuals with no HSCR were included, for which coding sequences (CDS) of 62 genes known to be in signaling pathways relevant to enteric nervous system development were selected for capture and sequencing. Blood DNAs from eight pools of five cases or controls were enriched by PCR-based RainDance technology (RDT) and then sequenced on a 454 FLX platform. As technical validation, five patients from case Pool-3 were also independently enriched by RDT, indexed with barcode and sequenced with sufficient coverage. Assessment for CDS single nucleotide variants showed DNA pooling performed well (specificity/sensitivity at 98.4%/83.7%) at the common variant level; but relatively worse (specificity/sensitivity at 65.5%/61.3%) at the rare variant level. Further Sanger sequencing only validated five out of 12 rare damaging variants likely involved in HSCR. Hence more improvement at variant detection and sequencing technology is needed to realize the potential of DNA pooling for large-scale resequencing projects. © 2014 John Wiley & Sons Ltd/University College London.postprin

    Smoke-free environment policy in Vietnam: What did people see and how did they react when they visited various public places?

    Get PDF
    Introduction: Since Vietnam has signed WHO framework on tobacco control (FCTC) in 2003 and has issued tobacco control law in 2013, there has been little research concerning about what impacts smoke-free regulations have had on public compliance. The objective of this study was to assess public exposure to secondhand smoke and reaction toward smoke-free policy regulations in Vietnam and the associated factor. Methods: Using the design of GATS (Global Adult Tobacco Survey), a nationally representative sample of 8,996 adults were approached for data collection. Logistic regression was used to examine the associated factor.Results: The study revealed that the prevalence of respondents exposed to secondhand smoke was much higher in bars/café/tea shops (90.07%) and restaurants (81.81%) than in any other public places, universities (36.70%), government buildings (31.12%), public transport (20.04%), healthcare facilities (17.85%) and schools (15.84%). 13.23% of respondents saw smokers violate smoke-free regulations. Among those who saw them violate smoke-free regulations, just one-third cautioned them to stop smoking. Strikingly, a higher rate of cautioning smokers to stop smoking was observed among the older, married, and better educated respondents. Respondents who were married, better educated and in lower economic status were more likely to remind smokers to stop smoking.Conclusions: The study has called for strengthening two of the six MPOWER (Monitor, Protect, Offer, Warn, Enforce and Raise) components of the tobacco free initiative introduced by WHO, Monitoring tobacco use and prevention policies and Protecting people from tobacco smoke
    corecore