56 research outputs found

    Revisiting Lifelong Learning and Its Practices in Vietnam

    Get PDF
    Education is an indispensable sector for a country's sustainable development. To maintain its continuity, government-based policies and related stakeholders in learning need to be considered to promote lifelong learning. This narrative literature review addresses international concepts of lifelong learning in Europe and how it has been implemented in Vietnam. The findings indicated that Vietnam faced more challenges than other developed countries, and some factors impacted LLL in Vietnam, such as legal frameworks, facilities, foreign language literacy, etc. The review also provided discussions for lifelong learning in Vietnam

    Isolation an agar degradation Bacillus sp. AT6 and preliminary application for seaweed saccharification

    Get PDF
    Background: Agar is a common polysaccharide found in nature. However, agar is strongly resisted to the degradation processing, leading to limitation of its application in various areas. Thus, finding an effective solution for agar saccharification significantly improves the economically effects of agar based substrates.Methods: Soil samples were collected from TienPhong Forestry Ltd. Company, ThuyXuan District, ThuaThien Hue province, Vietnam. Potential agar degrading bacteria were screened on a mineral salt agar medium. The isolate was identified based on 16S rRNA nucleotide sequence, morphological, physiological, and biochemical characteristics. Agarase production was evaluated by modification culture conditions including incubation time, shaking speed, and initial inoculum size. Molecular mass of extracellular agarase was determined by native SDS-PAGE. The effect of pH, temperature, metal ions, and organic solvents were conducted for enzyme characterization. Application of enzyme was investigated on seaweed saccharification.Result: An agar degrading bacterial strain was isolated from soils and identified as Bacillus sp. AT6. Maximal agarase accumulation obtained in the culture containing an inoculum size of 10% (v/v), shaking speed of 210 rpm, and 96 hours incubation. The agarase revealed a single band on zymogram analysis with an apparent molecular weight of 180 kDa. The optimal temperature and pH were 40°C and pH 8.0, respectively. All tested metal ions and organic solvents partially decreased enzyme activity. Treatment seaweed by agarase resulted in reducing sugars release present in the reaction, indicating the saccharification of seaweed was succeeded.Conclusion: Bacillus sp. AT6 is a new report of agarolytic bacteria that produces extracellular agarase enzymes. The present results promise strain AT6 is a great candidate for agar saccharification for industrial application

    Saponins isolated from the Vietnamese sea cucumber Stichopus chloronotus.

    Get PDF
    Using various chromatographic methods, three triterpene saponins neothyonidioside (1), stichoposide D (2), and holothurin B (3), were isolated from the methanol extract of the sea cucumber Stichopus chloronotus. Their structures were elucidated by 1D and 2D-NMR experiments and comparison of their NMR data with reported values. Compound 1 was isolated from S. chloronotus for the first time

    Morphometrics allometry changes and sexual dimorphism in Caragobius urolepis (Gobiiformes: Gobiidae)

    Get PDF
    The present study reported an alternative way of sex-determining for scaleless worm goby Caragobius urolepis based on the regression relationship of some morphological parameters. A total of 328 samples were collected at the trawl nets in two coastal regions in Bac Lieu and Ca Mau from April to August 2022. After collection, the samples were transported to the laboratory in order to measure the total length (TL), body height (BD), head length (HL), the distance of eye (DE), and mouth width (MD) before surgery for accurate sex determination based on gonads. Regression analysis results of TL-BD (growth pattern A+ in females and I in males), TL-HL (growth pattern A+ in females and A- in males), and TL- MD (growth pattern A- in females and A+ in males) could be used to determine the sex of this fish. Moreover, TL-DE and TL-BD could be used to estimate when the samples were collected, e.g , in the dry or wet season, because DE and BD displayed A+ in the wet season but A- in the dry one. The findings could be used as an alternative way to determine fish sex and catching season for this species and others in the Mekong Delta

    The impacts of lead recycling activities to human health and environment in Dong Mai craft village, Hung Yen, Vietnam

    Get PDF
    Lead (Pb) recycling activities in Dong Mai village, Chi Dao commune, Van Lam district, Hung Yen province have been taking place for more than 30 years. The development of recycling activities contributed to the improvement of the local economics. However, along with economic development, Dong Mai craft village is facing to serious pollution. Soil, air and water polluted by lead (Pb) caused food containing Pb at higher levels than allowed limit from 20 to 40 times. The pollution had the bad effect on human health in this village. The investigation results showed that 100 % of employee who participated on melting lead and 63.5 % of local children were poisoned by Pb. Besides, the local people got diseases relating to skin, eyes, etc. This situation requires the provincial authorities to find immediate solutions to reduce the impacts of Pb recycling activities to environment and human.Hoạt động tái chế chì của thôn Đông Mai, xã Chỉ Đạo, huyện Văn Lâm, tỉnh Hưng Yên đã diễn ra hơn 30 năm nay. Sự phát triển của nghề tái chế đã làm góp phần cải thiện kinh tế của địa phương. Tuy nhiên, cùng với sự phát triển kinh tế, làng nghề Đông Mai đã và đang đối mặt với ô nhiễm môi trường nghiêm trọng. Môi trường đất, nước không khí bị ô nhiễm bởi chì (Pb) dẫn đến thực phẩm nhiễm chì ở hàm lượng cao hơn mức cho phép từ 20- 40 lần. Sự ô nhiễm gây ra những ảnh hưởng xấu tới sức khỏe của người dân làng nghề. Kết quả điều tra cho thấy 100% công nhân tham gia nấu chì và 63.5% trẻ em địa phương bị nhiễm độc chì. Bên cạnh đó, người dân địa phương còn bị mắc của các loại bệnh ngoài da, bệnh về mắt, …. Tình trạng này đòi hỏi chính quyền địa phương phải tìm ra giải pháp khẩn cấp để giảm thiểu tác động của những hoạt động tái chế chì tới môi trường và con người

    Sex differentiation via the relationship between some morphological measurements of Mystus albolineatus caught from Cai Rang - Can Tho and Long Phu - Soc Trang

    Get PDF
    This study supplements the gender determination methodology based on the relationship of some morphological indicators in Mystus albolineatus. A total of 229 specimens were caught by trawl nets at Cai Rang – Can Tho and Long Phu – Soc Trang in four months from April to July 2023. After collection, the samples were transferred to the laboratory to determine the total length (TL), standard length (SL), eye diameter (ED), eye distance (DE), body height (BH), head length (HL), and mouth diameter (MD) before surgery to determine the sex based on the gonad. The results showed that the TL-SL regression relationship could be used to determine the sex of this fish. Besides, TL-BH and TL-MD growth relations were relatively balanced in females versus males. In addition, based on SL, DE, and MD, it was also possible to determine whether the sampling time was the wet or dry seasons. These findings form the basis for the initial study of the biological characteristics of this fish in the Mekong Delta

    ẢNH HƯỞNG CỦA DỊCH CHIẾT VI KHUẨN LAM ĐẾN NHÂN GIỐNG IN VITRO CÂY LAN HOÀNG THẢO GIẢ HẠC (Dendrobium anosmum Lindl.)

    Get PDF
    Protocorms of 4-week-old Dendrobium anosmum Lindl. were used as initial material for in vitro propagation. The stock extract of Arthrospira sp. was prepared by grinding 1 g of fresh biomass in 100 mL of distilled water. The in vitro propagation results show that the cyanobacterial extract has the effect of enhancing shoot multiplication and rooting of Dendrobium anosmum. An MS basal medium supplemented with 6 g·L–1 agar, 30 g·L–1 saccharose, and 1.5 mg·L–1 BAP in combination with 20 mL·L–1 cyanobacteria extract was suitable for protocorm multiplication with a protocorm cluster diameters of 2.43 cm. An MS medium supplemented with 6 g·L–1 agar, 30 g·L–1 sucrose, and 1.0 mg·L–1 BAP combined with 20 mL·L–1 cyanobacterial extract was optimal for shoot multiplication. The number of shoots/explant reached 4.7 and a shoot height of 1.37 cm. An MS medium supplemented with 6 g·L–1 agar, 30 g·L–1 sucrose, and 1.5 mg·L–1 NAA in combination with 30 mL·L–1 cyanobacteria extract was the most suitable for rooting with 4.87 roots/bud; the root length was 0.74 cm, and the shoot height was 2.76 cm. These results would open up the application of cyanobacterial extract to reduce costs in plant tissue culture technology.Protocorm của cây lan Hoàng thảo Giả hạc (Dendrobium anosmum Lindl.) bốn tuần tuổi được sử dụng để làm vật liệu khởi đầu cho nhân giống in vitro. Dịch chiết gốc vi khuẩn lam Arthrospira sp. được tạo thành bằng cách nghiền 1 g sinh khối tươi trong 100 mL nước cất. Kết quả cho thấy dịch chiết vi khuẩn lam có tác dụng tăng cường sự nhân chồi và ra rễ của cây lan Hoàng thảo Giả hạc nuôi cấy in vitro. Môi trường MS cơ bản bổ sung 6 g·L–1 agar, 30 g·L–1 saccharose và 1,5 mg·L–1 BAP kết hợp với 20 mL·L–1 dịch chiết vi khuẩn lam thích hợp cho sự nhân protocorm và môi trường tối ưu cho nhân chồi. Đường kính cụm protocorm thu được là 2,43 cm. Môi trường MS cơ bản bổ sung 6 g·L–1 agar, 30 g·L–1 saccharose và 1,0 mg·L–1 BAP kết hợp với 20 mL·L–1 dịch chiết vi khuẩn lam là môi trường tối ưu cho nhân chồi, số chồi/mẫu đạt 4,7; chồi cao 1,37 cm. Môi trường MS cơ bản bổ sung 6 g·L–1 agar, 30 g·L–1 saccharose và 1,5 mg·L–1 NAA kết hợp với 30 mL·L–1 dịch chiết vi khuẩn lam thích hợp nhất cho tạo rễ từ chồi in vitro với 4,87 rễ/chồi; chiều dài rễ là 0,74 cm và chiều cao chồi là 2,76 cm. Kết quả này sẽ mở ra triển vọng ứng dụng dịch chiết vi khuẩn lam giúp giảm chi phí trong công nghệ nuôi cấy mô tế bào thực vật

    Chemical Constituents and Bacterial Activity of Essential Oils of Five Wax Apples (Syzygium samarangense) from Dong Thap Province, Vietnam

    Get PDF
    In the present study, essential oils from the leaves of five varieties of wax apple trees, (\u27An Phuoc\u27, \u27Hoa An\u27, \u27Hong Dao\u27, \u27Sua\u27, and \u27Xanh Duong\u27) collected in Dong Thap Province, Vietnam were isolated using hydrodistillation, and their constituents were for the first time identified via gas chromatography - mass spectrometry. A total of 74 compounds from essential oils were identified. These compounds were classified into four clusters by hierarchical clustering analysis. The main constituents of the essential oils isolated from the leaves of five varieties of wax apple trees were o-cymene, α-cubebene, epizonarene, β-gurjunene, and α-selinene. The antibacterial activity of the essential oils isolated from the leaves of five varieties of wax apples were evaluated for the first time. The results showed that the essential oils could inhibit the growth of four tested microorganisms: Bacillus cereus, Escherichia coli, Salmonella enteritidis and Staphylococcus aureus
    corecore