EFL HIGH-SCHOOL TEACHERS’ PRACTICES OF STRATEGIES FOR CRITICAL THINKING INSTRUCTION IN WRITING CLASSES

This study aims to investigate EFL high-school teachers’ practices of strategies for CT instruction in their writing classrooms. The study was designed as a mixed-method one, using a questionnaire, and classroom observation as collecting data instruments. The sample consists of 103 EFL teachers from 21 high schools in Camau province, in the Mekong Delta region for quantitative data; five out of 103 teachers were purposely chosen to be observed to collect qualitative data. The finding of the study revealed that EFL high-school teachers’ practices of CT strategies used in writing classrooms were at a high level but at the lowest rate. At the same time, the results from classroom observation showed that EFL teachers used three more including setting real writing tasks, presentation, and student questioning in addition to the seven CT strategies presented in the research. From the findings, some pedagogical implications and recommendations are promoted in the hope that EFL teachers can effectively employ strategies for teaching CT in writing classrooms. Finally, the study’s limitations and suggestions for further research were also highlighted.  Article visualizations

An insight into non-English major learners’ task engagement from a sociocultural perspective

Under the lens of a sociocultural view, this qualitative study was conducted with 83 non-English major learners at a university in the Mekong Delta to examine English learners’ task engagement. Twelve of them were further invited to be interviewed. Data were collected from class observations, learning journals, semi-structured interviews and stimulated recall. The study showed that the same task was performed differently by learners, and that the way learners implemented a given task was shaped by the negotiation between their personal and contextual factors because of their sense of agency in the situated sociocultural learning context. The study has acquired an increased insight into learners’ task engagement regarding their agency in the teaching and learning context of Vietnam from a sociocultural view

VIETNAMESE STUDENT RESEARCHERS’ EXPECTATIONS OF THEIR SUPERVISOR AND SUPERVISION PROCESS

In Vietnam, scientific research is no longer just the work of scientists, graduate students, scholars, or lecturers; tertiary students are also encouraged to conduct scientific research. Therefore, the scientific research work of students receives more attention from educators. The research on carrying out scientific research of students is also therefore increasing. However, researchers do not seem to have paid enough attention to the role of supervisors during the supervision process. The evidence is that there are few studies on supervisors in Vietnam. Therefore, this study was conducted to learn about the role of supervisors from the student's perspective and expectations. Specifically, this study was conducted quantitatively with the use of a questionnaire consisting of 49 questions with a 5-point Likert scale. A total of 100 English-major students at a university in Southwest Vietnam participated in this study by answering the questionnaire. The results from the questionnaire show that students had high expectations from their supervisors. Specifically, students expect their supervisor to be someone who respects their opinions, has good scientific research knowledge, can give constructive comments, and is always willing to help them when needed. Based on research findings, supervisors are encouraged to participate in professional development training related to scientific research to improve their research knowledge and skills. Along with that, supervisors need to be aware of their role during the process of guiding students to do scientific research.  Article visualizations

Isolation and characterization of Rhizobium spp. and Bradyrhizobium spp. from legume nodules

Rhizobia topic has been re-focused in recent years because of new findings on their traits not only as nitrogen-fixing bacteria but also as plant growth-promoting rhizobacteria. When combing rhizobial strains with novel biological carriers (e.g., biochar) for inoculant production, it brings great potential for improving soil health in long-term. Appreciating this trend, this study is designed to isolate and characterize local rhizobial strains from legume fields using the conventional method with some modifications to increase efficiency in rhizobial identification. As a result, 17 rhizobial strains were isolated and classified biochemically that genetic identification outcome confirmed 10 strains belong to 07 different Rhizobium species as R. mayense, R. paknamense, R. pusense, R. miluonense, R. tropici, R. phaseoli, and R. multihospitium while the rest belong to 06 various Bradyrhizobium species as B. elkanii, B. centrosematis, B. guangxiense, B. liaoningense, B. yuanmingense, and B. arachidis. Thermal and saline tolerant tests together with seed germination tests also performed on these rhizobial strains to gain data on their responses to abiotic stresses. By comparing rice and mung bean GI values, we can assess the effectiveness of each rhizobial strains to help seeds at their early germination

PRELIMINARY STUDY ON CHEMICAL MECHANISM OF DECREASE OF TETRODOTOXIN CONTENT IN OVARIES OF A PUFFER FISH Lagocephalus inermis (Temminck and Schlegel, 1850) FERMENTED WITH RICE BRAN

Tetrodotoxins in salted and fermented ovaries with rice bran of a puffer fish Lagocephalus inermis (Temminck Schlegel, 1850) during five months were determined by high-performance liquid chromatography with fluorometric detector (HPLC- FLD). The analysed results showed that the original ovaries contained only tetrodotoxin with content of 7.59 µg/g fresh weight. 4,9-Anhydrotetrodotoxin - an isomer which is less toxic than tetrodotoxin has been found in all ovary samples since the second month. Tetrodotoxin in the ovaries disappeared in the 4th month of the experiment. In addition, 4,9-anhydrotetrodotoxin level in ovaries increased during fermentation. The present study contributes to clarifying the chemical mechanism of decreasing tetrodotoxin content in fermented ovary of puffer fish.Tetrodotoxins in salted and fermented ovaries with rice bran of a puffer fish Lagocephalus inermis (Temminck and Schlegel, 1850) during five months were determined by high-performance liquid chromatography with fluorometric detector (HPLC- FLD). The analysed results showed that the original ovaries contained only Tetrodotoxin with content of 7.59 µg/g fresh weight. 4,9-Anhydrotetrodotoxin- an isomer which is less toxic than Tetrodotoxin has been found in all ovary samples since the second month. Tetrodotoxin in the ovaries disappeared in the 4th month of the experiment. In addition, 4,9-Anhydrotetrodotoxin level in ovaries increased during fermentation. The present study contributes to clarify the chemical mechanism of decreasing Tetrodotoxin content in fermented ovary of puffer fish

MỘT SỐ ĐẶC TÍNH CỦA CANXI HYDROXYAPATIT CHIẾT XUẤT TỪ XƯƠNG CÁ NGỪ VẰN Katsuwonus pelamis

This paper is concerned with certain properties of calcium hydroxyapatite from skipjack tuna bone (Katsuwonus pelamis) which are by-products of fish export industry. Hydroxyapatite Ca10(PO4)6(OH)2 and β-tricalcium phosphate Ca3(PO4)2, the high-value compounds, have been successfully extracted from skipjack tuna bones. The bones were heated at different temperatures of 600oC, 900oC, 1200oC. While at 600oC hydroxyapatites were obtained with Ca/P ratio of 1.658, comparable to the value of 1.67 found in human bone; the hydroxyapatite crystals of average size of 0.25 µm were formed with the same size distribution. In case of heated bone samples at 900°C and 1200°C, the calcium formed were biphasic calcium phosphate composed of hydroxyapatite and β-tricalcium phosphate; the Ca/P ratio was between 1.660–1.665; the calcium crystals of more than 1 µm were highly porous and connected to each other in priority orientation of tube direction.Bài báo này trình bày kết quả nghiên cứu về một số đặc tính của canxi hydroxyapatit chiết xuất từ xương cá ngừ Katsuwonus pelamis, một sản phẩm phụ từ ngành xuất khẩu thịt cá ngừ. Các hợp chất có giá trị là hydroxyapatit Ca10(PO4)6(OH)2 và β-tricanxi phosphat β-TCP Ca3(PO4)2 đã được chiết xuất thành công từ xương cá ngừ vằn. Xương cá ngừ được nung ở các nhiệt độ khác nhau 600, 900 và 1.200oC. Dạng canxi thu được khi nung mẫu ở 600oC là hydroxyapatit với tỉ lệ Ca/P 1,658 gần với tỉ lệ Ca/P 1,67 trong xương người; các tinh thể hydroxyapatit có kích thước trung bình 0,25 µm và sự phân bố kích thước tương đối đồng đều. Đối với mẫu xương được xử lý ở 900 và 1.200oC, canxi thu được là hỗn hợp hai pha hydroxyapatit Ca10(PO4)6(OH)2 và β-tricanxi phosphat Ca3(PO4)2; tỉ lệ Ca/P từ 1,660–1,665, các tinh thể canxi có độ xốp cao và liên kết với nhau theo hướng ưu tiên kiểu hình ống với kích thước lớn hơn 1 µm

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.

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

PHENOLIC COMPOUNDS FROM CALLISTEMON CITRINUS LEAVES AND STEMS

In the search for bioactive constituents from Vietnamese plants,  the leaves and stems of Callistemon citrinus (Curtis) Skeels were selected for chemical investigation. Phytochemical analysis of plant led to the isolation of eight phenolic compounds including two flavonoids (eucalyptine (1) and 8-demethyleucalyptine (2)), two alcohols (blumenol A (3), n-tetratriacontanol (4)), three benzoic acid derivatives (acid gallic (5), methyl gallate (6) protocatechuic acid (7)), one sterol (b-sitosterol (8)), and along with one sesquiterpene (2,6,10-bisabolatriene (9)). The structures of the natural compounds were determined by spectroscopic evidences including 1D- and 2D-NMR and ESI-MS

Synthesis and redetermination of the crystal structure of salicyl-aldehyde <i>N</i>(4)-morpholino-thio-semi-carbazone.

The structure of the title compound (systematic name: N-{[(2-hy-droxy-phen-yl)methyl-idene]amino}-morpholine-4-carbo-thio-amide), C12H15N3O2S, was prev-iously determined (Koo et al., 1977 ▸) using multiple-film equi-inclination Weissenberg data, but has been redetermined with higher precision to explore its conformation and the hydrogen-bonding patterns and supra-molecular inter-actions. The mol-ecular structure shows intra-molecular O-H⋯N and C-H⋯S inter-actions. The configuration of the C=N bond is E. The mol-ecule is slightly twisted about the central N-N bond. The best planes through the phenyl ring and the morpholino ring make an angle of 43.44 (17)°. In the crystal, the mol-ecules are connected into chains by N-H⋯O and C-H⋯O hydrogen bonds, which combine to generate sheets lying parallel to (002). The most prominent contribution to the surface contacts are H⋯H contacts (51.6%), as concluded from a Hirshfeld surface analysis

Cyanide detoxification efficiency of injection and soak of hydroxocobalamin, sodium nitrite and sodium thiosulfate for sea water ornamental fish

The Oceanographic Museum offers interesting exhibits of several marine lives for tourist sightseeing and entertainment. These sea water ornamental fish are all caught in the wild. However, its health can be affected by cyanide poisoning during human fishing. Depending on the level of cyanide poisoning, fish can die after one and two weeks that caused economic damages for the museum. The present study is concerned with results of cyanide detoxification by using direct injection into cinnamon clownfish or soak of hydroxocobalamin, sodium nitrite and sodium thiosulfate with the aim of improving the health, survival and life time for fish, contributing to increasing economic efficiency for the Oceanographic Museum