Science and Technology Development Journal http://stdj.scienceandtechnology.com.vn/index.php/stdj <p><span id="result_box" class="" lang="en"><span title="Tạp chí Phát triển Khoa học và Công nghệ (PTKH&amp;CN) của Đại học Quốc gia thành phố Hồ Chí Minh (ĐHQG-HCM) được thành lập từ năm 1997, ra số đầu tiên vào tháng 1 năm 1998. Từ năm 2006 Tạp chí đã"><strong>Science and Technology Development Journal</strong> (STDJ), Vietnam National University - Ho Chi Minh City (VNU-HCM) was established in 1997. And the first issue was published in January 1998 with </span><span title="đăng ký mã số chuẩn quốc tế ISSN 1859-0128.">ISSN 1859-0128. </span><span title="Từ đó cho đến nay, Tạp chí PTKH&amp;CN đã trở thành diễn đàn khoa học quan trọng nhất của đội ngũ cán bộ nghiên cứu, giảng viên, nghiên cứu sinh của ĐHQG-HCM và cũng là diễn đàn khoa học công nghệ đáng tin cậy của">Since then, STDJ has become the most important scientific forum of scientists from VNU-HCM as well as</span><span title="nhiều nhà nghiên cứu, giảng viên các trường đại học khác tại Việt Nam."> other universities. </span><span title="Tạp chí đã trải qua 20 năm phát triển và đã trở thành nhịp cầu giao lưu khoa học, cũng như làm phong phú tài liệu tham khảo cho đội ngũ giảng viên, nghiên cứu sinh, sinh viên ĐHQG-HCM nói riêng và các Trường đại">The magazine has undergone 20 years of development and has become a bridge for scientific exchanges, as well as enriching reference materials for the faculty, doctoral students, students of VNU-HCM in particular and other universities, institutes... </span></span></p> <p><span id="result_box" class="" lang="en"><span title="học phía Nam nói chung. "><br></span><span title="Tính đến hết năm 2016 Tạp chí đã xuất bản được 276 số với 2714 bài nghiên cứu của các nhà khoa học, cán bộ trong và ngoài ĐHQG-HCM trong 5 lĩnh vực nghiên cứu: Kỹ thuật và Công nghệ, Khoa học Tự nhiên,">By the end of 2016, the journal has published 276 issues with 2714 research articles in five areas of research: Engineering and Technology, Natural Sciences, </span><span title="Khoa học Xã hội và Nhân văn, Kinh tế luật và Khoa học Quản lý, Khoa học Trái đất và Môi trường tương ứng với 5 chuyên san chuyên ngành của Tạp chí.">Social Sciences and Humanities, Economics of Law and Management Sciences, Earth Sciences and Environment corresponding to 5 specialized journals of the Journal. </span></span></p> <p><span id="result_box" class="" lang="en"><span title="Tạp chí đã được phát hành tại các thư viện của các đơn vị thành viên của ĐHQG-HCM, các Sở Khoa học Công nghệ của các tỉnh thành trên cả nước và được Hội đồng học hàm Giáo sư Nhà nước đánh giá cao.">The magazine has been widely indexed in the various libraries at Vietnam. </span></span></p> <p><span id="result_box" class="" lang="en"><span title="Từ tháng 12/2006 Tạp chí đã nhận được sự giúp đỡ của tổ chức mạng quốc tế về các xuất bản phẩm khoa học thuộc Hội đồng khoa học quốc tế để tham gia vào mạng lưới các Tạp chí Khoa học quốc tế. "><br></span><span title="Hiện nay tạp chí bao gồm 5 chuyên san sau đây: ">The journal currently consists of the following five sections:<br></span><span title="• Kỹ thuật và Công nghệ, ">• Engineering and Technology</span></span></p> <p><span id="result_box" class="" lang="en"><span title="• Khoa học Tự nhiên, ">• Natural Sciences</span></span></p> <p><span id="result_box" class="" lang="en"><span title="• Khoa học Xã hội và Nhân văn, ">• Social Sciences and Humanities</span></span></p> <p><span id="result_box" class="" lang="en"><span title="• Kinh tế luật và Khoa học Quản lý, ">• Economics, Law and Management</span></span></p> <p><span id="result_box" class="" lang="en"><span title="• Khoa học Trái đất và Môi trường">• Sciences of Earth and Environment</span></span></p> <p><span class="" lang="en"><span title="• Khoa học Trái đất và Môi trường"><span id="result_box" class="" lang="en">• Health Sciences : It includes work from basic science, clinical science, dental, nursing and other related medical fields. <br></span></span></span></p> Viet Nam National University Ho Chi Minh City en-US Science and Technology Development Journal 1859-0128 <p>Copyright The Author(s) 2018. This article is published with open access by Vietnam National University, Ho Chi Minh city, Vietnam. This article is distributed under the terms of the&nbsp;<a href="https://creativecommons.org/licenses/by/4.0/" target="_blank" rel="noopener">Creative Commons Attribution License (CC-BY 4.0)</a> which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.&nbsp;</p> The suitable distribution area of artichoke (Cynara scolymus L.) in the Hoang Lien Son Mountain range (Lao Cai Province) http://stdj.scienceandtechnology.com.vn/index.php/stdj/article/view/3802 <p>Hoang Lien Son is a high, rugged mountain range in the northwest region of Vietnam where many ethnic minorities gather, and due to socioeconomic characteristics, the life of the people here still faces many difficulties. Artichoke is a medicinal plant with high economic value and favorable growth in temperate climates and is one of the options for sustainable economic development for people in mountainous areas. The study used a multicriteria analysis method on AHP to analyze the influence of ecological factors of the Hoang Lien Son area (Lao Cai Province) on the growth and development of artichokes. The weights from the AHP model are used to establish ecological adaptation maps through geographic information system (GIS) software. The research results show that the most suitable areas (S1 and S2) for the development of artichokes have an area of 125,642.72 hectares, accounting for 34.41% of the study area. However, the area with the highest adaptability (S1) for growing artichokes is not large, located at an altitude of over 1000 m, mainly at 1700 m in the territory of Sapa town and some communes in Bat Xat district. The results provide the scientific basis for planning potential planting areas and exploiting and developing artichokes to improve livelihoods and people's lives, contributing to biodiversity conservation and sustainable development.</p> Truong Ngoc Kiem Nguyen Ngoc Cong ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2022-05-11 2022-05-11 25 2 2354 2363 10.32508/stdj.v25i2.3802 title description none g DFT insight into the high stability of single Pt atoms on the CeO2(111) surface http://stdj.scienceandtechnology.com.vn/index.php/stdj/article/view/3890 <p><strong>Introduction</strong>: Single Pt atom catalysts supported on CeO2(111) surfaces have attracted considerable attention in recent years due to their high reactivity and selectivity in important reactions, such as water–gas shift reactions for hydrogen production and CO oxidation. However, the geometrical and electronic structure of Pt/CeO2(111) at the atomic level is still not clearly understood. In this study, we aim to gain insight into the geometrical and electronic structure of a single Pt atom on the CeO2(111) surface.</p> <p><strong>Methodology</strong>: Various single Pt atom species, including (Pt)ads, (PtOH)ads, (PtO)ads, (PtO2H2)ads, (PtO2)ads, (Pt)subCe, and (Pt)subO, deposited on the CeO2(111) surface were investigated by the DFT+U method with dispersion corrections. Furthermore, the CO molecule was adopted to evaluate the electronic structures of these single Pt atoms. In addition, the supported Pt3 cluster was applied as a metallic model to distinguish it from single Pt atom models.</p> <p><strong>Results</strong>: By comparing the CO adsorption properties of single Pt atom models and Pt3 cluster models to those of experimental observations in the literature, the stretching frequency of CO on (PtO2)ads species agrees well with the experimental results, while the frequencies of CO on other single Pt atom structures and on Pt3 clusters largely differ from the experimental results.</p> <p><strong>Conclusion</strong>: Based on the DFT calculated results, we conclude that the activity and high stability of single Pt atom species that were observed from the experiment are formed via the interaction between Pt and two extra O atoms on the CeO2(111) surface.</p> Thang Viet Ho Hop Quy Van Thong Le Minh Pham ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2022-05-11 2022-05-11 25 2 2364 2372 10.32508/stdj.v25i2.3890 title description none g Chemical constituents of the lichen Usnea lapponica Vain., Parmeliaceae http://stdj.scienceandtechnology.com.vn/index.php/stdj/article/view/3896 <p><strong>Introduction</strong>: The lichen Usnea lapponica Vain. belonging to the Usnea genus (family Parmeliaceae) grow hanging from tree branches in the damp forest at Bidoup Nui Ba National Park, Dam Rong district, Lam Dong province. In addition, this lichen has not yet been chemically and biologically studied. The primary goal of the present work was to study the chemical constituents of the lichen Usnea lapponica Vain.</p> <p><strong>Methods</strong>: A dried powder of thalli Usnea lapponica Vain. was extracted by maceration with MeOH at ambient temperature to prepare the crude MeOH extract. This crude extract was subjected to silica gel column chromatography with gradient polar solvent including n-hexane, CHCl3, EtOAc, and MeOH to separate into different polar fractions. The chemical structures of the isolated compounds were elucidated through the interpretation of their 1D and 2D NMR and HRESIMS data.</p> <p><strong>Results</strong>: In this paper, we reported the isolation of six known compounds, including two depsides lecanorin (1) and isolecanoric acid (2), two depsidones norstictic acid (3) and methylstictic acid (4), an ergosterol, 22E,24R-5α,6α-epoxyergosta-8,22-diene-3β,7α-diol (5), and lupeol (6).</p> <p><strong>Conclusion</strong>: This is the first time that these compounds have been reported from Usnea lapponica Vain.</p> Nguyen Huu Tri Dung Thi My Nguyen ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2022-05-11 2022-05-11 25 2 2373 2380 10.32508/stdj.v25i2.3896 title description none g Omicron: Flighty factor challenging global vaccine campaigns or the ending signal of the COVID-19 pandemic http://stdj.scienceandtechnology.com.vn/index.php/stdj/article/view/3895 <p>Coronavirus disease 2019 (COVID-19) has been a great global public health issue for two years. In November 2021, a new variant, B.1.1.529, of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified in South Africa and caused a rapid rise in COVID-19 cases. On 26 November 2021, the World Health Organization (WHO) named this variant Omicron and classified it as a variant of concern (VoC). The spike protein of this variant contains a high number of mutations, raising concerns about viral transmissibility, pathogenicity, immune evasion, and neutralization by antibodies. When the early Omicron surge occurred, preliminary data showed that the transmission of this variant was extremely fast, but the number of patients with severe symptoms was low. This review will describe the characteristics of the Omicron variant and compare the mutations of the spike in the five VoCs. We also look over research and opinions on the Omicron variant and evaluate epidemiological data from the Omicron wave and the Delta wave. In the review discussion, we will discuss Omicron whether it is a challenge for global vaccine campaigns, whether it is a sign of a waning pandemic, and how we acknowledge the new variant and future of the COVID-19 pandemic.</p> Giang Thi Kim Lien Nguyen Thi Bao Anh Le Nguyen Thien Han Le Tu Manh Huy Le Thi Ngoc Tam Nguyen Tran Phuoc Thuan Hien Minh Nguyen ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2022-05-02 2022-05-02 25 2 press press 10.32508/stdj.v25i2.3895 title description none g Breast cancer diagnosis based on detecting lymph node metastases using deep learning http://stdj.scienceandtechnology.com.vn/index.php/stdj/article/view/3894 <p><strong>Introduction</strong>: Automated detection of metastatic breast cancer from whole slide images of lymph nodes utilizing a deep convolutional neural network was proposed in this study.</p> <p><strong>Methods</strong>: The dataset is taken from the PatchCamelyon subset, which contains 220,025 images divided into training, validation, and testing sets at a ratio of 60:20:20. The pretrained ResNet50 model was utilized, and transfer learning was subsequently applied to adjust the weights of the model. To elevate the model performance, the evaluation metrics were assessed by the accuracy score, confusion matrix, receiver operating characteristic (ROC) curve, and area under the ROC curve (AUC) score.</p> <p><strong>Results</strong>: As a result, the proposed algorithm obtained high performance, with scores over 95% in all the evaluation methods, especially the AUC score, which achieved 0.989. Moreover, the model is validated in a testing set with the test-time augmentation (TTA) technique to enhance prediction quality and reduce generalization error.</p> <p><strong>Conclusion</strong>: Overall, the proposed model achieves high accuracy when applying transfer learning. The results prove that the trained Resnet50 model can extract useful information from small cells in histopathologic images for breast cancer detection.</p> Bich Ha Thach Nguyen Bich Ngoc Le Trinh Ngoc Huynh Hai Thanh Le Thu Hien Thu Pham ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2022-05-12 2022-05-12 25 2 2381 2389 10.32508/stdj.v25i2.3894 title description none g