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Genetic diversity in two threatened species in Vietnam:Taxus chinensis and Taxus wallichiana

Journal of Forestry Research 2017年第2期28卷 265-272页

作者： dinh Duy vu Thi Tuyet Xuan Bui Minh Tam Nguyen dinh giap vu Minh Duc Nguyen Van Thang Bui Xiaohua Huang Yi Zhang College of Forestry Northwest A&F UniversityYangling 712100ShaanxiPeople's Republic of China Vietnam National Museum of Nature Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Ecology and Biological Resource(VAST) 18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Natural Products Chemistry(VAST) 18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Forest Biotechnology Vietnam Forestry UniversityXuan MaiChuong MyHanoiVietnam

Taxus chinensis and T. wallichiana in have been threatened in their distribution areas in recent decades because of their over-exploitation and reduction and destruction of native habitats. Determining the genetic diversity in populations of the two species will provide guidelines for their protection and preservation. Two hundred and fifteen trees from six populations of T. chinensis and150 sampled trees of T. wallichiana were sampled. Six microsatellite primer pairs selected from 16 primer pairs were used to investigate genetic variation at the population and species levels. Five yielded polymorphic alleles, and among the 13 putative alleles amplified, 11 were polymorphic（accounting for 76.33 %）.Shannon＇s information index（I） and percentage of polymorphic bands（PPB）（I = 0.202 and PPB = 67.22 % for T. chinensis; I = 0.217 and PPB = 65.03 % for T. wallichiana）. Both species had low levels of genetic diversity（mean Ho= 0.107, He= 0.121 for T. chinensis; Ho= 0.095, He= 0.109 for T. wallichiana）. Genetic differentiation among populations was higher（FST= 0.189） for T. chinensis and lower（0.156） for ***, indicating limited gene flow（Nm） among populations for T. chinensis（0.68） and T. wallichiana（0.65）.Variation among individuals of T. chinensis was 63.59 and73.12 % for T. wallichiana. Thus, the threatened status of the two conifers is related to a lack of genetic diversity. All populations are isolated in small forest remnants. An ex situ conservation site should be established with a new population for these species that comprises all the genetic groups for the best chance to improve their fitness under environmental stresses.

关键词： Taxus populations alleles polymorphic microsatellite Vietnam primer accounting putative destruction

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Genetic diversity and conservation of two threatened dipterocarps(Dipterocarpaceae) in southeast Vietnam

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Journal of Forestry Research 2019年第5期30卷 1823-1831页

作者： dinh-Duy vu Thi Tuyet-Xuan Bui Minh-Duc Nguyen Syed Noor Muhammad Shah dinh-giap vu Yi Zhang Minh-Tam Nguyen Xiao-Hua Huang College of Forestry Northwest A&F UniversityYanglingShaanxi 712100People’s Republic of China Vietnam National Museum of Nature Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Ecology and Biological Resource Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam Department of Horticulture Faculty of AgricultureGomal UniversityDera Ismail KhanPakistan Institute of Natural Products Chemistry Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam

Two threatened dipterocarp species,Dipterocarpus costatus and Dipterocarpus alatus are well-known endangered species in lowland forests of southeastern Vietnam,primarily from habitat loss and over-exploitation of their *** develop conservation strategies for these species,we analyzed 242 samples using nine microsatellite markers to determine the genetic variability within and among five populations of *** and three of ***,representing the natural range of dipterocarps in Southeast *** indicated low levels of genetic variability within populations with an average gene diversity of 0.223 for *** and 0.152 for *** of bottleneck tests indicated a reduction in population size of both species(P>0.05).Genetic differentiation among populations was high(FST=0.347 for *** and 0.274 for ***),indicating limited gene flow(Nm=0.662 for *** and 0.47 for ***)and isolated populations related to geographical *** of molecular variance showed high genetic variation within populations(72.92%for *** and 60.81%for ***)compared to among *** analysis and UPGMA tree also indicated the two optimal genetic clusters related to geographical *** results will provide a platform for the conservation,management and restoration of these species.

关键词： Dipterocarps Genetic conservation Gene diversity SSR primers

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Application of machine learning technique for predicting and evaluating chloride ingress in concrete

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Frontiers of Structural and Civil Engineering 2022年第9期16卷 1153-1169页

作者： Van Quan TRAN Van Loi giap dinh Phien vu Riya Catherine GEORGE Lanh Si HO Department of Civil Engineering University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

The degradation of concrete structure in the marine environment is often related to chloride-induced corrosion of reinforcement ***,the chloride concentration in concrete is a vital parameter for estimating the corrosion level of reinforcement *** research aims at predicting the chloride content in concrete using three hybrid models of gradient boosting(GB),artificial neural network(ANN),and random forest(RF)in combination with particle swarm optimization(PSO).The input variables for modeling include exposure condition,water/binder ratio(W/B),cement content,silica fume,time exposure,and depth of *** results indicate that three models performed well with high accuracy of prediction(R2⩾0.90).Among three hybrid models,the model using GB_PSO achieved the highest prediction accuracy(R2=0.9551,RMSE=0.0327,and MAE=0.0181).Based on the results of sensitivity analysis using SHapley Additive exPlanation(SHAP)and partial dependence plots 1D(PDP-1D),it was found that the exposure condition and depth of measurement were the two most vital variables affecting the prediction of chloride *** the number of different exposure conditions is larger than two,the exposure significantly impacted the chloride content of concrete because the chloride ion ingress is affected by both chemical and physical *** study provides an insight into the evaluation and prediction of the chloride content of concrete in the marine environment.

关键词： gradient boosting random forest chloride content concrete sensitivity analysis

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Technical Procedure Determination of Thoron Indoor Concentration by LR-115 Type II

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Journal of Environmental Science and Engineering(B) 2016年第3期5卷 109-114页

作者： Nguyen Thi Thu Ha Frinh Van giap Le dinh Cuong Center for Environmental Radiation Monitoring and Impact Assessment Institute for Nuclear Science and Technology (INST)Vietnam Atomic Energy Institute (VINATOM) Hanoi 100000 Vietnam

Thoron （Rn-220） is an invisible, odorless radioactive gas and nine times heavier than air. Purpose of project is to set up procedure to determine Rn-220 concentration which has been carried out in laboratory using Solid State Nuclear Track Detector （SSNTD） based passive detector technique. In this study, technical procedure has been applied in Karlsruhe diffusion chamber and LR-115, Type II strippable （Kodak Pathe, France） detector. The results have investigated how LR-115 work for Rn-220 by using Monazite ore to simultaneously measure Rn-222 and Rn-220. To carry out experiment, Karlsruhe diffusion chamber is used to with and without Poly-Ethylene （PE） membrane. Karlsruhe diffusion chamber with PE membrane only detect Rn-222, without PE membrane detect total Rn-222 and Rn-220. Precision evaluation by duplicate measure at 8 cm detector-source distance with relative standard deviation is less than 2.54%. Testing technical procedure, detectors have been sent to National Institute of Radiological Science （NIRS） for Rn-220 calibration exposure. After detectors have been calibration exposure at NIRS, it carried out all the following steps of procedure which set up at laboratory in 1NST, Vietnam. Finally, calibration factor calculated is 0.21 （tracks-cm2/Bq·m3·h） and constructed curve between integrated Tn-220 concentration and tracks density with factor R2 = 0.975.

关键词： LR-115 type-II (SSNTDs) Rn-220 spark counter.

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Assessment of Radiation Dose Caused by Radioactive Gaseous Effluent Released from Nuclear Power Plant Ninh Thuan 1 under Scenario of Normal Working Conditions

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World Journal of Nuclear Science and Technology 2015年第3期5卷 183-191页

作者： Nguyen Tuan Khai Do Xuan Anh Le dinh Cuong Duong Duc Thang vuong Thu Bac Nguyen Thi Thu Ha Nguyen Quang Long Trinh Van giap Nguyen Hao Quang Institute for Nuclear Science and Technology (INST) Hanoi Vietnam Vietnam Atomic Energy Institute (VINATOM) Hanoi Vietnam

Based on guides RG 1.109, RG 1.111 published by United States Nuclear Regulatory Commission (USNRC), our research concentrates in assessing radiation doses caused by radioactive substances released from the nuclear power plant (NPP) Ninh Thuan 1 under the scenario of normal operation using software package NRCDose72 provided by the USNRC. The database including the released radioactive nuclides, meteorology, terrain, population and agricultural production activities have been collected and processed to build the input data for the model calculation. The wind rose distribution obtained from the meteorological data in a five-year period from 2009-2013 showed that the radioactive nuclides released to environment spread in two main wind directions which are North East and South West. The X/Q (s/m3) and D/Q (s/m2) qualities which are, respectively, the ratio of activity concentration to release rate and that of deposition density of radioactive nuclides to release rate were calculated within an area of 80 km radius from the NPP site using XOQDOQ. Population doses were calculated using GASPAR. The XOQDOQ and GASPAR are two specific softwares in NRCDose72 package.

关键词： NPP Radioactive Release Radiation Dose Population Dose X/Q and D/Q

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