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CURRENT BIODIVERSITY AND THE CHALLENGES FOR BIODIVERSITY CONSERVATION IN THE PU MAT NATIONAL PARK 普马特国家公园生物多样性现状及保护面临的挑战
Journal of Science Natural Science Pub Date : 2022-10-01 DOI: 10.18173/2354-1059.2022-0053
Nhung Tran Thi, H. Nguyen Van, Cam Lai Vinh, Nhat Vuong Hong, Hiền Nguyễn Thị Thu, Thao Nguyen Phuong, Thanh Nguyen Duc, Quan Luong Viet
{"title":"CURRENT BIODIVERSITY AND THE CHALLENGES FOR BIODIVERSITY CONSERVATION IN THE PU MAT NATIONAL PARK","authors":"Nhung Tran Thi, H. Nguyen Van, Cam Lai Vinh, Nhat Vuong Hong, Hiền Nguyễn Thị Thu, Thao Nguyen Phuong, Thanh Nguyen Duc, Quan Luong Viet","doi":"10.18173/2354-1059.2022-0053","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0053","url":null,"abstract":"This research synthesizes the most advanced progress on biodiversity in recent decades to develop a set of information about the current condition of biodiversity in the Pu Mat national park. Data was collected from reliable documents nationally, updated statistics, and maps from management committees associated with field surveys in the study area. After implementing data synthesis, analysis, and inheritance from the previous related research and using a geographic information system (GIS), the findings indicated that: 1) Pu Mat National Park protects the rare genetic resources of Vietnam, which include 2600 floral species, 1121 animal species, and four typical ecosystems of evergreen- broadleaf natural forest, mixed wood-bamboo ecosystem, natural bamboo ecosystem and grassshrubs ecosystem; 2) establishing an ecosystem map based on the integration of the forest current maps, forest inventory maps, land use current maps in Pu Mat National Park area, scale 1:50,000; and 3) identifying factors challenging in biodiversity conversation in Pu Mat national park. The main challenging factors present, (1) the need of using biodiversity resources; (2) the urbanization process; (3) the interference with the environment and habitat from human beings; (4) climate change; and (5) the development of tourism. Understanding the current state of the study area and gaining a comprehensive understanding of biodiversity would allow for the most feasible and practical conservation strategies to be suggested for Pu Mat National Park.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"182 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82331757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
COHEN-MACAULAYNESS OF SOME EDGE-WEIGHTED GRAPHS 一些边加权图的Cohen-macaulayness
Journal of Science Natural Science Pub Date : 2022-10-01 DOI: 10.18173/2354-1059.2022-0037
Diem Ly Thi Kieu, Nguyen Nguyen Phung
{"title":"COHEN-MACAULAYNESS OF SOME EDGE-WEIGHTED GRAPHS","authors":"Diem Ly Thi Kieu, Nguyen Nguyen Phung","doi":"10.18173/2354-1059.2022-0037","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0037","url":null,"abstract":"In this paper, we will study the characterization of Cohen-Macaulayness of some edge-weighted graphs. For cycle and tree edge-weighted graph, we will reprove the characterization of Cohen-Macaulayness of an edge-weighted cycle and an edge-weighted tree due to C.Paulsen and Wagstaff (2013) [1]. Our proof used a criterion of Hochster for Cohen-Macaulayness of a monomial ideal [2].","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"106 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78058373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
SODIUM SULFIDE-PROMOTED REACTION OF 2-AMINOBENZAMIDE AND BENZYL ALCOHOLS WITH ELEMENTAL SULFUR: A NOVEL APPROACH WITH 2-ARYL-QUINAZOLIN-4(3H) 硫化钠促进2-氨基苯甲酰胺和苯甲醇与单质硫的反应:2-芳基喹唑啉-4(3h)的新方法
Journal of Science Natural Science Pub Date : 2022-10-01 DOI: 10.18173/2354-1059.2022-0044
Oanh Doan Thi Yen, Binh Vo Ngoc, Anh Ngo Quoc
{"title":"SODIUM SULFIDE-PROMOTED REACTION OF 2-AMINOBENZAMIDE AND BENZYL ALCOHOLS WITH ELEMENTAL SULFUR: A NOVEL APPROACH WITH 2-ARYL-QUINAZOLIN-4(3H)","authors":"Oanh Doan Thi Yen, Binh Vo Ngoc, Anh Ngo Quoc","doi":"10.18173/2354-1059.2022-0044","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0044","url":null,"abstract":"A simple metal- and solvent-free method for the synthesis of 2-aryl- 4(3H)-quinazolinone derivatives from 2-aminobenzamide and benzyl alcohols in the presence of S8DMSO as an oxidizing agent and promoted by Na2S.5H2O has been reported. Five 2-aryl-4(3H)-quinazolinone derivatives were synthesized with yields from 23% to 86%.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72887956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
OPTIMIZING GENOTYPING PROCEDURE AND DETERMINING FREQUENCY OF SINGLE NUCLEOTIDE POLYMORPHISM RS7799039 BELONGING TO LEP GENE IN FOUR-YEAR-OLD BOYS IN HANOI 河内地区4岁男孩lep基因rs7799039单核苷酸多态性基因分型方法优化及频率测定
Journal of Science Natural Science Pub Date : 2022-10-01 DOI: 10.18173/2354-1059.2022-0051
Thu Nguyen Thi Trung, Minh Pham Bui Quang, Tuyet Le Thi
{"title":"OPTIMIZING GENOTYPING PROCEDURE AND DETERMINING FREQUENCY OF SINGLE NUCLEOTIDE POLYMORPHISM RS7799039 BELONGING TO LEP GENE IN FOUR-YEAR-OLD BOYS IN HANOI","authors":"Thu Nguyen Thi Trung, Minh Pham Bui Quang, Tuyet Le Thi","doi":"10.18173/2354-1059.2022-0051","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0051","url":null,"abstract":"The LEP (leptin) gene plays an important role in the regulation of food intake and energy metabolism. The single nucleotide polymorphism (SNP) rs7799039 located in the promoter of the LEP gene may affect the risk of obesity and other diseases such as diabetes, cardiovascular disease, cancer, etc. due to altering the gene expression. The objective of this study is to find out the optimum procedure for genotyping SNP rs7799039 by using the polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP) method and determine the allele and genotype frequencies of this SNP in 61 four-year-old boys with normal nutritional status in Hanoi. The sequence of primers has been designed as follows: forward primer 5'-tttcctgtaattttcccatgag-3' and reverse primer 5'-aaagcaaagacaggcataaaa-3'. The thermal cycle for the PCR reaction includes initiation at 94 °C (3 minutes), 34 cycles of denaturation at 94 °C (30 seconds), annealing at 56 °C (30 seconds), extension at 72 °C (30 seconds), final extension at 72 °C (8 minutes), and then keep the products chilling at 4 °C. HhaI restriction enzyme was used to distinguish A and G alleles of rs7799039. PCR products are incubated with 0.5 µl HhaI restriction enzyme for 15 minutes at 37°C and then the products of restriction enzyme digestion are separated by gel electrophoresis. Genotype frequencies of our studied population are 62.3% AA, 31.1% AG, and 6.6% GG (P HWE = 0.452).","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84080902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
CHANGES IN LIVING CONDITIONS, LIFESTYLE, AND BEHAVIORS OF HIGH SCHOOL STUDENTS DURING THE COVID-19 PANDEMIC IN VIETNAM 新冠肺炎疫情期间越南高中生生活条件、生活方式和行为的变化
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0032
Dung Le Thi Thuy, Thuy Dao Thi, Thuong Nguyen Hoai, Tuyet Le Thi
{"title":"CHANGES IN LIVING CONDITIONS, LIFESTYLE, AND BEHAVIORS OF HIGH SCHOOL STUDENTS DURING THE COVID-19 PANDEMIC IN VIETNAM","authors":"Dung Le Thi Thuy, Thuy Dao Thi, Thuong Nguyen Hoai, Tuyet Le Thi","doi":"10.18173/2354-1059.2022-0032","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0032","url":null,"abstract":"This study was performed to clarify the impacts of the COVID-19 pandemic on high school children's living conditions, lifestyle, living and studying habits. Cross-sectional research was conducted on 2369 high school students, selected from several high schools in Hanoi, Thanh Hoa, Thai Binh, and Dak Lak provinces. The result showed that during the COVID-19 epidemic period, living conditions were changed, such as isolation in the living area (22.1% of participants), reduced family income (35.9% of participants’ fathers and 37.3% of participants’ mothers salary decreased). Most children must switch to online learning (67.6%), and children tended to sleep later and wake up later (16.7% and 11.2%). Children tended to eat more meals and much food each meal than before. The percentage of children who spent over 3 hoursday using electronic devices increased during the COVID-19 epidemic (54.8% compared to 33.8% before). Our findings indicated that the COVID-19 pandemic had adverse effects on children's living conditions, lifestyles, and habits.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"31 3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76382053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
DETERMINING THE THERMODYNAMIC DISSOCIATION CONSTANTS OF 5-BROMO-6,7-DIHYDROXY-N-METHYL-3-SULFOQUINOLINE IN AQUEOUS SOLUTION AT 25 OC BY POTENTIOMETRIC METHOD 用电位法测定了5-溴-6,7-二羟基- n -甲基-3-磺基喹啉在25℃水溶液中的热力学解离常数
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0027
Nga Tran The, Anh Nguyen Thi Mai
{"title":"DETERMINING THE THERMODYNAMIC DISSOCIATION CONSTANTS OF 5-BROMO-6,7-DIHYDROXY-N-METHYL-3-SULFOQUINOLINE IN AQUEOUS SOLUTION AT 25 OC BY POTENTIOMETRIC METHOD","authors":"Nga Tran The, Anh Nguyen Thi Mai","doi":"10.18173/2354-1059.2022-0027","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0027","url":null,"abstract":"In this report, the thermodynamic dissociation constants of 5-bromo-6,7- dihydroxy-N-methyl-3-sulfoquinoline (signed H2BDMS) acid were firstly determined in the aqueous solution using potentiometric titration at (25.0 ± 0.1) oC in the ionic medium of 0.10 M KCl solution. This new acid is a compound containing the quinoline ring that may be applied in many branches of chemistry, biology, and medicine. The pKa values of H2BDMS acid which were determined by the potentiometric method are pKa1 = 2.79 ± 0.02 and pKa2 = 7.80 ± 0.06. To increase the precision and accuracy of the results, the pKa values were calculated at various concentration levels. The structure of the new acid and data of potentiometric titration were analyzed in detail before calculating and assigning the pKa values to suitable functional groups. These results will be applied to our further studies of this compound.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"114 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76679192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
ASSESSMENT OF IMPACTS OF THE ROAD SYSTEM ON FLOOD REGIME IN THE COASTAL FLOODING AREA OF VU GIA - THU BAN RIVER BASIN, QUANG NAM PROVINCE 广南省武家图班河流域沿海洪涝区道路系统对洪情的影响评价
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0034
Son Hoang Thanh, Hanh Le Duc, Dang Vu Hai, Tuan Bui Anh, Yen Nguyen Thi Hai, Tuan Tong Phuc
{"title":"ASSESSMENT OF IMPACTS OF THE ROAD SYSTEM ON FLOOD REGIME IN THE COASTAL FLOODING AREA OF VU GIA - THU BAN RIVER BASIN, QUANG NAM PROVINCE","authors":"Son Hoang Thanh, Hanh Le Duc, Dang Vu Hai, Tuan Bui Anh, Yen Nguyen Thi Hai, Tuan Tong Phuc","doi":"10.18173/2354-1059.2022-0034","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0034","url":null,"abstract":"Flooding is one of the dangerous types of natural disasters, which has been causing great damage to human values and even human life, leading to negative impacts on socio-economic development, specifically in the lowland areas of the Vu Gia - Thu Bon river basin. The road system contributes to promoting intra-regional and inter-regional connectivity and is an important factor for socio-economic development. However, in certain cases, the road system continues to be expanded and enhanced, turning them into \"dyke systems\", interfering with the natural flood regime, increasing the area and flooding time. To assess the impact of the road system on the flood regime, the paper uses the Mike Flood modeling module to simulate the change of flood regime for flood events in 1999, 2007, 2020, and the 5% flood scenario. The comparison between the current road system and the old road system shows a certain increase in both depth and flooded area, especially in the case of 5% flood, the flood depth increases by 0.1 - 0.2 m in the upper part of the basin but only a small change in the lower part of the basin from 0.01 - 0.04 m.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75147177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
RESEARCH ON THE CONSTRUCTION OF A PHANTOM IN DOSE CALCULATION BY PHITS SIMULATION PROGRAM 用phits模拟程序构建剂量计算中虚影的研究
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0022
Hung Bui Tien, Duong Tran Thuy, Ha Bui Ngoc, Thao Nguyen Thi
{"title":"RESEARCH ON THE CONSTRUCTION OF A PHANTOM IN DOSE CALCULATION BY PHITS SIMULATION PROGRAM","authors":"Hung Bui Tien, Duong Tran Thuy, Ha Bui Ngoc, Thao Nguyen Thi","doi":"10.18173/2354-1059.2022-0022","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0022","url":null,"abstract":"In the field of medical physics, determining the dosage for organs is a very complex problem because it is impossible to directly measure the dosage inside a living person's body. Therefore, in order to estimate the dosage, one usually has to use phantoms. For dosage determination and safety assessment, Monte Carlo simulation programs and today's phantoms have become indispensable tools. There are already several standard phantoms in the world but they do not represent biological characteristics by region or for a specific object. Another method used to build characteristic phantoms is done through computed tomography (CT) images and the Hounsfield index. The method requires to convert the grayscale value of each pixel element into the Hounsfield index. As such, it can only be applied to CT imaging. To overcome this shortcoming, this study has developed a program based on a new process that can convert images to geometric format for MCNPPHITS. The new procedure that we propose will allow researchers to describe the anatomical structures more accurately and be specific to each patient.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89879437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
GRADED VERSION OF EXEL’S EFFROS-HAHN CONJECTURE FOR LEAVITT PATH ALGEBRAS 关于leavitt路径代数的exel effros-hahn猜想的分级版本
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0020
Loc Nguyen Quang, Ha Le Thi
{"title":"GRADED VERSION OF EXEL’S EFFROS-HAHN CONJECTURE FOR LEAVITT PATH ALGEBRAS","authors":"Loc Nguyen Quang, Ha Le Thi","doi":"10.18173/2354-1059.2022-0020","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0020","url":null,"abstract":"In this paper, we prove a graded version of Exel’s Effros-Hahn conjecture for Leavitt path algebras. More concretely, we show that any graded primitive ideal of the Leavitt path algebra is the annihilator of a module induced from a graded simple module over an isotropy group algebra. A graded version of Steinberg’s results towards Exel’s conjecture in (B. Steinberg, Ideals of etale ´groupoid algebras and Exel’s Effros-Hahn conjecture, J. Noncommut. Geom., Vol. 15, 2021, pp. 829-839) is also obtained for graded ample groupoid algebras.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80883338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
SOME GEOMETRIC CHARACTERIZATIONS OF EXTREMAL SETS IN HILBERT SPACES Hilbert空间中极值集的一些几何特征
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0019
Khiem Nguyen Van
{"title":"SOME GEOMETRIC CHARACTERIZATIONS OF EXTREMAL SETS IN HILBERT SPACES","authors":"Khiem Nguyen Van","doi":"10.18173/2354-1059.2022-0019","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0019","url":null,"abstract":"Based on our previous result and by using the technique on α-minimal and χ-minimal sets with respect to the Kuratowski and Hausdorff measures of noncompactness, we give some new geometric characterizations of extremal sets in Hilbert spaces.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"359 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76420216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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