71 research outputs found

    Preschool STEM Activities and Associated Outcomes: A Scoping Review

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    This review highlights the need for further investigation into the benefits of STEM activities in preschool children’s learning, girls’ engagement and learning of children with disabilities in the STEM field. The review process involved accessing 19 relevant studies from Scopus, ERIC and Google Scholar databases in March 2023. Through the synthesis of information from these studies, seven STEM activities were identified as effective in enhancing preschool children’s learning: educational robots, educational games, argumentative interactions, inquiry-based learning and engineering design, drawing and telling about engineers, free play and pretend play, and group membership. Each of these activities contributes to different learning outcomes for children. Moreover, the review emphasizes the importance of role-playing activities ‘as if’ engineers and scientists, facilitated by teachers, in fostering girls’ motivation and engagement in the STEM field from an early age. Long-term scientific interventions at home have a significant positive impact on the science literacy skills of deaf children. The implications of this review are particularly relevant for early childhood educators, as it provides valuable insights into the use of STEM activities to enhance children’s learning outcomes

    Genetic Diversity and Population Structure of Canarium tramdenum Dai and Yakovl. in Northern Vietnam

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    Canarium tramdenum occurs naturally in subtropical and tropical regions of Indochina and China. The wood is used for making high quality furniture and the fruit and leaves are used in traditional medicine. However, a lack of information on genetic diversity and population structure has handicapped the genetic conservation and domestication of this high-value species. This study evaluated genetic variation within and among four C. tramdenum populations. Sixty individuals were collected from four natural populations in Vietnam in the provinces of Ninhbinh, Bacgiang, Nghean, and Backan. Genetic diversity and genetic structure were determined using 20 ISSR markers. A total of 192 DNA fragments with sizes ranging from 110 bp to 3,000 bp were detected, of which 154 segments (80.2%) were polymorphic and 38 segments (19.8%) were monomorphic. The ISSR data indicated a moderate degree of genetic diversity for the species (h = 0.252). The four populations were separated into three genetic clusters with low levels of genetic distance between them. AMOVA result showed that most (78%) of the genetic variation was within the populations. The moderate to high genetic diversity of C. tramdenum and the low genetic differentiation among populations suggested that all existing natural populations in the particular regions needed to be preserved to protect the genetic diversity of this species

    Targeting effect of folate on cancer cell through curcumin carrier nano-system

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    Folate receptor (FR) is well known for its overexpression on surface of various cancer cell lines, which is identical to normal tissue. Folic-based targeting drug delivery systems, therefore, are one of the most effective targeting carriers that effectively bind to FR up-regulated cancer cells. Curcumin was used both for labeling and chemotherapy. The materials were characterized and structurally confirmed by FT-IR spectra, fluorescent images and FE-SEM images. Bioassays were conducted on HeLa and HT29 cancer cell lines after 4 and 12 hours. Results show that folic acid significantly enhanced both targeting efficiency and internalization of curcumin to FR-expressing cancer cells

    Complete mitochondrial genome of Dong Tao chicken breed (Gallus gallus domesticus) of Vietnam

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    The complete mitochondrial genome of Dong Tao chicken breed (Gallus gallus domesticus, Dong Tao) was obtained by PCR and sequencing. The complete mitogenome was 16,783 bp in length, with the nucleotide composition for A, T, C, G was 30.29%, 23.75%, 32.48%, and 13.48%, respectively. The mitogenome of Dong Tao chicken contained a non-coding control region (D-loop), 2 rRNA genes, 13 protein-coding genes, and 22 tRNA genes. Phylogenetic analysis revealed that breed Dong Tao chicken breed was sister-close to G. gallus breed Guangxi, and paraphyletic to G. spadiceus, S. jabouillei, and a range of Chinese indigenous, ie. breeds Rugao and Taoyuan

    Level of Factors impact on the Buyers’ Intention in Buying Private Health Insurance with the Case of Vietnam Non-Life Insurance Companies

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    The study aims to determine the influence of factors affecting the intention to purchase private health insurance at non-life insurance companies in Vietnam. The samples were surveyed from 500 people from many areas but mostly in Hanoi. The study identified and clarified 5 independent factors affecting the intention to buy private health insurance at non-life health insurance companies in Vietnam. The analysis results show 5 variables: "Past experience", "Perception of service quality of insurance companies", "Perceived behavioral control", "Attitude towards risks and private health insurance ", and the variable "Subjective norms on private health insurance" affect people's intention to buy private health insurance. Several policies have been proposed to increase customers' intention to buy private health insurance at non-life insurance companies from the analysis. To raise customer's intention to purchase private health insurance, the research team recommends non-life insurance company to improve service quality, especially after-sales service, the quality and expertise of staff, and the government to complete policies and legal framework on private health insurance. Moreover, the research team also recommend to renovate the quality of organizing the private health insurance regime and form the basis of the entire population pathology record. Keywords: private health insurance, intention to purchase, non-life insurance company. DOI: 10.7176/EJBM/12-27-06 Publication date:September 30th 202

    NGHIÊN CỨU TỐI ƯU ĐIỀU KIỆN BIỂU HIỆN INTERLEUKIN-3 NGƯỜI DUNG HỢP VỚI PelB TRONG E. coli

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    Interleukin-3 (IL-3) is a multifunctional cytokine which modulates the proliferation, differentiation and maturation of various types of hematopoietic cells. Gene coding for IL-3 linked with pelB signal were incorporated into pET22b(+) for  expression of il3 gene in E. coli BL21; but IL-3 was synthesized at very low levels and still in fusion with PelB. To facilitate purification process, finding the appropriate fermentation conditions plays a key role in order to enhance gene il-3 expression and cleavage of PelB. In this study, we have optimized the conditions for the expression of IL-3, which included E. coli host strain JM109, LB cultivation medium, induction temperature was 25oC; induction with 0.05 mM IPTG at OD600 = 1. The cell biomass increases at about 2.3 times after optimization. IL-3 protein was expressed in the form of inclusion body and the PelB signal was cleaved. This result is conducive for purification of large amount of IL-3 to determine characteristics of protein. Interleukin-3 người (IL-3) là một cytokine đa chức năng tham gia vào các quá trình tự đổi mới, nhân lên, biệt hóa và trưởng thành của nhiều loại tế bào máu. Sau khi đưa gen il-3 gắn thêm tín hiệu tiết pelB vào vector pET22b(+) và tiến hành biểu hiện ở chủng E. coli BL21, chúng tôi nhận thấy IL-3 được tổng hợp ở mức rất thấp và còn gắn với PelB. Để thuận tiện cho khâu tinh sạch thì vấn đề then chốt là nghiên cứu tìm ra các điều kiện phù hợp làm tăng lượng IL-3 được tổng hợp, đồng thời cắt được PelB. Trong nghiên cứu này, chúng tôi so sánh khả năng sinh tổng hợp IL-3 của các chủng E. coli BL21, JM109, Soluble và Rossetta2; sau đó tối ưu hóa điều kiện biểu hiện gen il-3 về thành phần môi trường, nhiệt độ, nồng độ IPTG, thời điểm cảm ứng và kiểm tra trạng thái tồn tại của IL-3. Kết quả thu được cho thấy gen il-3 biểu hiện tốt và ổn định nhất ở chủng E. coli JM109. Dưới các điều kiện lên men thích hợp trong môi trường LB, ở 25oC, cảm ứng 0,05 mM IPTG tại OD600=1, IL-3 biểu hiện tốt, cắt khỏi PelB và tồn tại ở trạng thái không tan trong tế bào chất. Sinh khối tế bào tăng lên khoảng 2,3 lần sau khi tối ưu. Kết quả này là tiền đề cho bước tinh sạch lượng lớn IL-3 cho nghiên cứu tính chất của protein

    Determinants of Green Banking Implementation in Emerging Country: Evidence from Vietnam Banks

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    With the purpose of examining which factors affecting on the implementation of ‘Green Banking’ in transitional countries, the research used in-depth interview and survey questionnaire with statistics analysis with the case of Vietnam banks. The results showed that in emerging country such as Vietnam, the level of ‘Green Banking’ implementation is most affected by Human determinant, followed by Strategy, Product & Services, Culture and Technology determinant respectively. Based on findings, several implications were proposed to enhance the performance of these kind of environment friendly financial products in transitional country. By determining these factors, the banking sector in transitional countries will enhance the implementation of ‘Green Banking’ and achieve sustainable development in the context of escalating environmental contamination. Keywords: Green Banking, Implementation, Emerging Country, Human DOI: 10.7176/EJBM/11-15-04 Publication date:May 31st 201

    Targeting effect of folate on cancer cell through curcumin carrier nano-system

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    Folate receptor (FR) is well known for its overexpression on surface of various cancer cell lines, which is identical to normal tissue. Folic-based targeting drug delivery systems, therefore, are one of the most effective targeting carriers that effectively bind to FR up-regulated cancer cells. Curcumin was used both for labeling and chemotherapy. The materials were characterized and structurally confirmed by FT-IR spectra, fluorescent images and FE-SEM images. Bioassays were conducted on HeLa and HT29 cancer cell lines after 4 and 12 hours. Results show that folic acid significantly enhanced both targeting efficiency and internalization of curcumin to FR-expressing cancer cells

    Chemical composition and cytotoxic activity of the essential oils of Cymbopogon citratus L. Grown in phu tho province

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    Culms and leaves of Cymbopogon citratus L. were collected from two regions of Phu Tho province (Thanh Son and Phu Ninh) and used as materials for essential oil extraction. Oils obtained were steam-distilled, analyzed for chemical composition and evaluated for cytotoxic activity against three different cancer cell lines. The GC/MS analysis showed that citral is the major content of the steam-distilled essential oils which was found in the range of 64.15-76.22%. Camphene was found only in culm oils of both regions but it was not detected in the leaf oils. Interestingly, the isomer forms of ocimene present at higher content in the culm oils than in the leaf oils whereas myrcene content in the leaf oils is higher than that in the culm oils. In a cytotoxicity test, four essential oils of culms and leaves of C. citratus from Thanh Son and Phu Ninh showed potent activity against A549 (human lung carcinoma) cell line with the IC50 values ranging from 4.01±0.39 to 6.3±0.54 µg/ml. The essential oils (culms and leaves) from Phu Ninh exhibited moderate effects on the Hela (human cervical adenocarcinoma) cells with the IC50 values of 19.43±1.16 and 42±2.41 µg/ml, respectively. However, they were inactive against the human hepatocellular carcinoma Hep3B cell line. The essential oils from Thanh Son exhibited potent cytotoxic activity against Hela and Hep3B cell lines with the IC50 values ranging from 1.18±0.26 to 8.91±0.32 µg/ml. The results indicated that the essential oils of C. citratus from Thanh Son, Phu Tho could be considered as a promising candidate for the natural sources of anticancer agents

    Nanoparticles as a control for cyanobacterial bloom

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    This study aims to investigate the toxicity of copper material synthesized by chemical reduction method and effects of environmental variables on growth of phytoplankton community (dominated by Microcystis genus) in the Tien eutrophic lake, Hanoi, Vietnam. The variables analyzed include: physical (pH and Turbidity), chemical (content of NH4+, PO43- and copper metal), biological (content of Chlorophyll-a, cell density). The characteristic of nanomaterial was confirmed by using UVvisible spectrophotometer, XRD, SEM and TEM methods. The CuNPs showed they spherical form and uniform size about 20-40 nm. The experimental results showed that the treated with CuNPs inhibition on growth against phytoplankton after 8 days. The cell density of phytoplankton community and Microcystis genus in samples exposure with CuNPs declined after 8 days from 647.037 and 467.037 down to 381.111 and 202.592, respectively.Mục đích của nghiên cứu này là khảo sát độc tính của vật liệu nano đồng được tổng hợp bằng phương pháp khử hóa học và ảnh hưởng của các yếu tố môi trường đến sinh trưởng và phát triển của quần xã thực vật nổi (chủ yếu là chi Microcystis) trong nước hồ Tiền phú dưỡng, tại Hà Nội, Việt Nam. Các thông số phân tích bao gồm: thủy lý (pH và độ đục), hóa học (hàm lượng amoni, photphat và hàm lượng đồng kim loại), sinh học (hàm lượng chất diệp lục, mật độ tế bào). Đặc trưng của vật liệu được xác định bằng các phương pháp quang phổ UV-VIS, XRD, SEM và TEM. Vật liệu nano đồng có dạng hình cầu, kích thước đồng nhất từ 20 đến 40 nm. Kết quả thử nghiệm sau 8 ngày cho thấy các mẫu có bổ sung vật liệu nano đồng ức chế sinh trưởng quần xã thực vật nổi ở nồng độ 1mg/l. Mật độ quần xã thực vật nổi và chi Microcystis trong mẫu xử lý với CuNPs đã giảm tương ứng sau 8 ngày từ 647.037 và 467.037 xuống còn 381.111 và 202.592
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