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基于Linkage Mapper的武汉市生态安全格局构建
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作者 严定华 周翔 +2 位作者 包丽艳 杨恩蕾 王鹏程 《城市建筑》 2024年第19期28-33,60,共7页
城市蓝绿空间对维持城市生态平衡具有重要作用,城市化的快速发展促使生态用地破碎化。文章以武汉市为研究对象,基于“生态源地识别—阻力面构建—生态廊道识别—战略节点识别”框架结合连通性构建生态安全格局。结果表明:①生态源地面积... 城市蓝绿空间对维持城市生态平衡具有重要作用,城市化的快速发展促使生态用地破碎化。文章以武汉市为研究对象,基于“生态源地识别—阻力面构建—生态廊道识别—战略节点识别”框架结合连通性构建生态安全格局。结果表明:①生态源地面积共3053.09 km^(2),空间上多集中于武汉市西北部、东南部和东北部。②阻力因子的选取包括土地利用、地形、人为干扰及生态保护四个方面,运用层次分析法得到各阻力因子权重分别为0.387、0.316、0.109和0.188,结合ArcGIS加权得到综合生态阻力值,在空间上呈现“中间高、四周低”的特征。③基于Linkage Mapper识别出生态廊道21条,共计1223.72 km,生态网络结构α指数为0.43、β指数为1.62、γ指数为0.64,重力模型筛选出的作用力大于15的一级廊道共8条。④识别出548个生态夹点,总面积2.7801 km^(2);473处生态障碍点,总面积8.874 km^(2)。 展开更多
关键词 linkage Mapper 生态安全格局 重力模型 MSPA
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An efficient method for constructing a random insertional mutant library for forward genetics in Nannochloropsis oceanica
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作者 Zhongyi ZHANG Hang LIU +5 位作者 Xiaohui PAN Yanan ZONG Leili FENG Lixian LIU Li GUO Guanpin YANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期216-225,共10页
Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-st... Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-strand breaks of DNA,causing insertional mutation.The random insertional mutant library constructed using this method has become a method of forward genetics for gene cloning.However,the establishment of a random insertional mutant library requires a high transformation efficiency of exogenous genes.Many microalgal species show a low transformation efficiency,making constructing random insertional mutant libraries difficult.In this study,we established a highly efficient transformation method for constructing a random insertional mutant library of Nannochloropsis oceanica,and tentatively tried to isolate its genes to prove the feasibility of the method.A gene that may control the growth rate and cell size was identified.This method will facilitate the genetic studies of N.oceanica,which should also be a reference for other microalgal species. 展开更多
关键词 Nannochloropsis oceanica genetic transformation random insertional mutant library zeocin pretreatment forward genetics
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Efficient User Identity Linkage Based on Aligned Multimodal Features and Temporal Correlation
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作者 Jiaqi Gao Kangfeng Zheng +2 位作者 Xiujuan Wang Chunhua Wu Bin Wu 《Computers, Materials & Continua》 SCIE EI 2024年第10期251-270,共20页
User identity linkage(UIL)refers to identifying user accounts belonging to the same identity across different social media platforms.Most of the current research is based on text analysis,which fails to fully explore ... User identity linkage(UIL)refers to identifying user accounts belonging to the same identity across different social media platforms.Most of the current research is based on text analysis,which fails to fully explore the rich image resources generated by users,and the existing attempts touch on the multimodal domain,but still face the challenge of semantic differences between text and images.Given this,we investigate the UIL task across different social media platforms based on multimodal user-generated contents(UGCs).We innovatively introduce the efficient user identity linkage via aligned multi-modal features and temporal correlation(EUIL)approach.The method first generates captions for user-posted images with the BLIP model,alleviating the problem of missing textual information.Subsequently,we extract aligned text and image features with the CLIP model,which closely aligns the two modalities and significantly reduces the semantic gap.Accordingly,we construct a set of adapter modules to integrate the multimodal features.Furthermore,we design a temporal weight assignment mechanism to incorporate the temporal dimension of user behavior.We evaluate the proposed scheme on the real-world social dataset TWIN,and the results show that our method reaches 86.39%accuracy,which demonstrates the excellence in handling multimodal data,and provides strong algorithmic support for UIL. 展开更多
关键词 User identity linkage multimodal models attention mechanism temporal correlation
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The Interventional Capacity of Community Health Volunteers for Screening and Linkages of Non-Communicable Diseases in Nyeri County, Kenya
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作者 Kenneth Mugambi Jackline Nyaberi Elizabeth Echoka 《Open Journal of Preventive Medicine》 2024年第4期61-78,共18页
Non-communicable diseases (NCDs) account for 63% of mortalities. Approximately 80% of these NCD-related deaths occur in LMICs. A quasi-experimental study utilizing a non-equivalent pre-and post-test was conducted from... Non-communicable diseases (NCDs) account for 63% of mortalities. Approximately 80% of these NCD-related deaths occur in LMICs. A quasi-experimental study utilizing a non-equivalent pre-and post-test was conducted from May 2022 to March 2023 with 370 study participants. Multistage cluster and random sampling were used to select ten community units, and therefore, 150 CHVs were chosen for the control unit, and 150 were used to form the interventional group. Data was collected from the KOBO app. Six (6) homogenous FGDs comprised ten members, and 10 KII were conducted across study sites. Quantitative data was analyzed using SPSS version 28.0, and qualitative data was audio-recorded, transcribed, and analyzed via N-Vivo 12. The study shows that 59.3% of respondents have minimal information, and 92.7% (n = 139) have no clear understanding of NCDs, with a pre-intervention capacity of 48.8%. Independent sample t-test showed a significant difference in capacity from a pre-intervention average of 48.75 (SD ± 5.7)%, which increased to 68.28 (SD ± 7.6)%, p < 0.001. A well-designed community interventional model plays a pivotal role in grassroots healthcare delivery but requires optimization for NCD management. 展开更多
关键词 INTERVENTION Community Health Volunteers Non-Communicable Disease SCREENING linkages
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New model of linkage evolution for the transtensional fault systems in the Nanpu Sag of Bohai Bay Basin:Insight from seismic interpretation and analogue modelling
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作者 Yu-Heng Wang Fu-Sheng Yu +1 位作者 Bao-Yin Zhao Ling-Jian Meng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2287-2310,共24页
The evolution of faults within the same stress field is frequently influenced by numerous factors,involving the reactivation of pre-existing structures,stress transmission through ductile detachment layers,and the gro... The evolution of faults within the same stress field is frequently influenced by numerous factors,involving the reactivation of pre-existing structures,stress transmission through ductile detachment layers,and the growth,interaction,as well as linkage of new fault segments.This study analyses a complex multi-phase oblique extension fault system in the Nanpu Sag(NPS)of the Bohai Bay Basin(BBB),China.High-resolution three-dimensional(3D)seismic data and analogue modelling indicate that the oblique extensional reactivation of pre-existing structures governs the sequential arrangement of fault segments in the caprock,and they dip synthetically to the reactivated fault at depth.During the NW-SE extension in the Eocene,the predominant movement of the pre-existing fault is strike-slip.Subsequently,during the N-S extension since the Oligocene,inclined at 20.to the pre-existing fault,forming splay fault segments and ultimately creating large en-echelon arcuate faults linked by relay ramps.Using fault throw-distance(T-D)and laser scanning,we reconstructed the fault evolution model of oblique extension reactivation in the presence of a ductile detachment basement.Our study illustrates that the arcuate faults can be categorized into linear master fault segments controlled by pre-existing structures,bending splay faults in the termination zone,and normal fault segments responding to the regional stress field.The interaction between faults occurs among normal faults and strike-slip faults,and the kinematic unification of the two fault systems is accomplished in the intersection zone.As the faults continue to evolve,the new fault segments tend to relinquish the control of pre-existing structures and concentrate more on the development of planar and continuous major faults.The ductile detachment layer significantly contributes to the uniform distribution of strain,resulting in narrow shear zones and discontinuous normal faults in its absence. 展开更多
关键词 Analogue modelling Transtensional deformation Fault linkage Fault intersection zone Nanpu Sag of Bohai Bay basin
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DeepSurNet-NSGA II:Deep Surrogate Model-Assisted Multi-Objective Evolutionary Algorithm for Enhancing Leg Linkage in Walking Robots
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作者 Sayat Ibrayev Batyrkhan Omarov +1 位作者 Arman Ibrayeva Zeinel Momynkulov 《Computers, Materials & Continua》 SCIE EI 2024年第10期229-249,共21页
This research paper presents a comprehensive investigation into the effectiveness of the DeepSurNet-NSGA II(Deep Surrogate Model-Assisted Non-dominated Sorting Genetic Algorithm II)for solving complex multiobjective o... This research paper presents a comprehensive investigation into the effectiveness of the DeepSurNet-NSGA II(Deep Surrogate Model-Assisted Non-dominated Sorting Genetic Algorithm II)for solving complex multiobjective optimization problems,with a particular focus on robotic leg-linkage design.The study introduces an innovative approach that integrates deep learning-based surrogate models with the robust Non-dominated Sorting Genetic Algorithm II,aiming to enhance the efficiency and precision of the optimization process.Through a series of empirical experiments and algorithmic analyses,the paper demonstrates a high degree of correlation between solutions generated by the DeepSurNet-NSGA II and those obtained from direct experimental methods,underscoring the algorithm’s capability to accurately approximate the Pareto-optimal frontier while significantly reducing computational demands.The methodology encompasses a detailed exploration of the algorithm’s configuration,the experimental setup,and the criteria for performance evaluation,ensuring the reproducibility of results and facilitating future advancements in the field.The findings of this study not only confirm the practical applicability and theoretical soundness of the DeepSurNet-NSGA II in navigating the intricacies of multi-objective optimization but also highlight its potential as a transformative tool in engineering and design optimization.By bridging the gap between complex optimization challenges and achievable solutions,this research contributes valuable insights into the optimization domain,offering a promising direction for future inquiries and technological innovations. 展开更多
关键词 Multi-objective optimization genetic algorithm surrogate model deep learning walking robots
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Interaction between diet and genetics in patients with inflammatory bowel disease
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作者 Daniéla Oliveira Magro Ligia Yukie Sassaki Júlio Maria Fonseca Chebli 《World Journal of Gastroenterology》 SCIE CAS 2024年第12期1644-1650,共7页
In this editorial,we comment on the article by Marangoni et al,published in the recent issue of the World Journal of Gastroenterology 2023;29:5618-5629,about“Diet as an epigenetic factor in inflammatory bowel disease... In this editorial,we comment on the article by Marangoni et al,published in the recent issue of the World Journal of Gastroenterology 2023;29:5618-5629,about“Diet as an epigenetic factor in inflammatory bowel disease”.The authors emphasized the role of diet,especially the interaction with genetics,in promoting the inflam-matory process in inflammatory bowel disease(IBD)patients,focusing on DNA methylation,histone modifications,and the influence of microRNAs.In this editorial,we explore the interaction between genetics,gut microbiota,and diet,in an only way.Furthermore,we provided dietary recommendations for patients with IBD.The Western diet,characterized by a low fiber content and deficiency the micronutrients,impacts short-chain fatty acids production and may be related to the pathogenesis of IBD.On the other hand,the consumption of the Mediter-ranean diet and dietary fibers are associated with reduced risk of IBD flares,particularly in Crohn’s disease(CD)patients.According to the dietary guidance from the International Organization for the Study of Inflammatory Bowel Diseases(IOIBD),the regular consumption of fruits and vegetables while reducing the consumption of saturated,trans,dairy fat,additives,processed foods rich in maltodextrins,and artificial sweeteners containing sucralose or saccharine is recommended to CD patients.For patients with ulcerative colitis,the IOIBD recommends the increased intake of natural sources of omega-3 fatty acids and follows the same restrictive recommendations aimed at CD patients,with the possible inclusion of red meats.In conclusion,IBD is a complex and hetero-geneous disease,and future studies are needed to elucidate the influence of epigenetics on diet and microbiota in IBD patients. 展开更多
关键词 DIET genetics MICRORNAS Gastrointestinal microbiome Inflammatory bowel diseases Crohn’s disease
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Constructing a Triangular Linkage Model of Government Audit,Social Audit,and Internal Audit to Promote High-Quality Development of Audit Services
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作者 TANG Pengzhan 《Journal of Modern Accounting and Auditing》 2024年第3期89-98,共10页
It is a complex and important topic to study the linkage mechanism of government audit,social audit,and internal audit in the context of China’s high-quality economic development.The implementation of measures,such a... It is a complex and important topic to study the linkage mechanism of government audit,social audit,and internal audit in the context of China’s high-quality economic development.The implementation of measures,such as establishing a sound and perfect organizational safeguard mechanism,strengthening project collaborative audit mechanism,enhancing the mechanism for utilizing audit results,and establishing an audit and rectification joint mechanism can promote the efficient operation of the audit supervision system and the high-quality development of audit services. 展开更多
关键词 government audit social audit internal audit triangular linkage model high-quality development
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基于Linkage Mapper模型的汉江生态城生态廊道构建与修复策略研究
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作者 朱捷缘 徐望朋 +3 位作者 边金云 熊东禹 张忠义 荣月静 《水利规划与设计》 2024年第12期25-30,59,共7页
生态廊道构建对于国土空间格局优化和绿色发展具有重要意义。文章以十堰市汉江生态城为例,以生物多样性维护重要区域为主要生态源地,选取土地覆被类型、地形、坡度、植被指数、距道路距离、距水域距离等因子构建景观综合阻力面,运用Link... 生态廊道构建对于国土空间格局优化和绿色发展具有重要意义。文章以十堰市汉江生态城为例,以生物多样性维护重要区域为主要生态源地,选取土地覆被类型、地形、坡度、植被指数、距道路距离、距水域距离等因子构建景观综合阻力面,运用Linkage Mapper模型构建生态廊道、识别生态障碍点。结果表明:(1)汉江生态城生态源地斑块共39处,面积为232.67km^(2);生态廊道共84条,长度合计108.36km。(2)生态障碍点28个,主要分布在南部和北部的耕地、村镇居民点、采矿用地、林灌植被等地类。(3)建议加强郊野区域农田边界景观营造,对采矿边坡采取绿化覆土种植措施,开展南部园岭山区域中幼林抚育提质,从而提升生境网络连通性。 展开更多
关键词 生态廊道 linkage Mapper模型 生态修复 汉江生态城
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A Theory of Bio-Quantum Genetics
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作者 Jianzhong Zhao 《Journal of Quantum Information Science》 CAS 2024年第1期15-27,共13页
The physical mechanism of heredity or inheritance of genes is a quantum mechanical and/or quantum computational process. A theory of bio-quantum genetics is established in this paper. Principle of Bio-quantum Genetics... The physical mechanism of heredity or inheritance of genes is a quantum mechanical and/or quantum computational process. A theory of bio-quantum genetics is established in this paper. Principle of Bio-quantum Genetics is suggested. I propose and define the soft-genes of genetics controlling the processes of heredity or inheritance of genes. This research deals with the quantum mechanisms of Mendel plant heredity and family inheritance as examples of bio-quantum genetics, deepening our understanding of heredity or inheritance. I believe that more contributions will be made to promote researches of bio-quantum genetics or quantum biology at large. 展开更多
关键词 Bio-Quantum genetics Quantum Mechanics GENES Soft Genes Quantum Mechanism of Mendel Plant Heredity Quantum Mechanism of Family Inheritance
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The Practice and Exploration of Applying EBM to Bilingual Teaching of Medical Genetics at OSBCM
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作者 Rong Liu Huaming Zuo 《Open Journal of Applied Sciences》 2024年第4期983-990,共8页
In the process of teaching medical genetics of undergraduate clinical medicine, the practice and exploration of applying EBM to the bilingual teaching of OSBCM medical genetics are carried out. Using CBL and PBL as th... In the process of teaching medical genetics of undergraduate clinical medicine, the practice and exploration of applying EBM to the bilingual teaching of OSBCM medical genetics are carried out. Using CBL and PBL as the carrier can make up for the shortcomings of a single teaching mode, synthesize the advantages of multiple teaching modes. It starts from integrating the basic theoretical knowledge of medicine and clinical practice knowledge, improving students’ bilingual level of medical genetics, cultivating students’ literature retrieval ability, and promoting early clinical, multi-clinical and repeated clinical consciousness for medical students. Therefore, it is more conducive to cultivate students’ ability to learn independently, accurately analyze and solve problems, improve medical students’ clinical thinking ability and scientific research awareness, improve medical students’ ability of international communication, and lay a solid foundation for improving medical students’ future post competence, innovative spirit and lifelong learning ability. 展开更多
关键词 Medical genetics Evidence Based Medicine Organ-System-Based Curriculum Model Problem Based Learning Case-Based Learning
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Chronic Hepatitis B in Indian Americans: Lack of Screening and Poor Linkage to Care
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作者 Chul Hyun Soonsik Kim +4 位作者 Emily Li Minhee Lee Mitchell K. Spinnell Joseph McMenamin Dohyun Cho 《International Journal of Clinical Medicine》 CAS 2024年第4期197-209,共13页
Background: Chronic hepatitis B (CHB) is a major cause of liver-related morbidity and mortality in the United States (US) and globally. CHB disproportionately affects Asian Americans and many other immigrant minority ... Background: Chronic hepatitis B (CHB) is a major cause of liver-related morbidity and mortality in the United States (US) and globally. CHB disproportionately affects Asian Americans and many other immigrant minority populations, primarily owing to the high prevalence of CHB in their countries of origin. India is a country with a medium-to-high prevalence of hepatitis B (HB) (>2%) and has over 40 million people infected with hepatitis B virus (HBV), with more than 115,000 deaths annually from HBV-related complications. Indian Americans are one of the largest immigrant populations in the US but remain underdiagnosed and poorly linked to clinical care. We, therefore, assessed the HBV prevalence and evaluated the linkage-to-care (LTC) among Indian Americans to develop strategic plans to reduce the impact of HBV in the US. Methods: Between April 2022 and January 2024, serologic screening and surveys were provided to 328 Indian American adults (age 20 - 80) in New York City. All participants were tested for a triple panel consisting of hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core IgG antibody (anti-HBc). A survey was conducted on the subjects chronically infected with HBV regarding their histories of infection. Self-administered questionnaires were employed to evaluate demographic and epidemiologic characteristics. Results: Of 328 screened and evaluated (246 males and 82 females), 10 (3.0%) were HBV-infected, 222 (67.7%) were susceptible to HBV, and 96 (29.3%) were immune. The prevalence of chronic HBV varied between the age groups: 4.6% (age 20 - 40), 3.4% (age 41 - 60), and 1.7% (age 61 - 80). Of 10 chronically infected, only two subjects had been previously diagnosed but were not engaged in care. Conclusion: HBV disproportionately affects Asian Americans, primarily owing to immigration from parts of the world where the disease is endemic. Indian Americans belong to an intermediate-risk group, with an HBV prevalence of >2%, but remain underdiagnosed and poorly linked to care. Our pilot study on Indian American populations, the first of its kind, demonstrates a 3% prevalence of CHB, none of whom are linked to care. In addition, this population has a high percentage of unimmune subjects, creating a large reservoir for future infection. With the growing population of Indian Americans, our findings can be used to develop community-based strategies for HBV screenings and LTC that target high-risk groups. 展开更多
关键词 Hepatitis B Virus Chronic Hepatitis B Indian Americans Health Disparity Community-Based Screening linkage-to-Care
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Rapid Constructing a Genetic Linkage Map by AFLP Technique and Mapping a New Gene tms5 被引量:9
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作者 贾建航 李传友 +1 位作者 邓启云 王斌 《Acta Botanica Sinica》 CSCD 2003年第5期614-620,共7页
In this study, we reported the repaid construction of a molecular marker linkage map of rice (Oryza sativa L.). An F-2 population from the cross between Annong S-1 and Nanjing 11 was used to construct a genetic linkag... In this study, we reported the repaid construction of a molecular marker linkage map of rice (Oryza sativa L.). An F-2 population from the cross between Annong S-1 and Nanjing 11 was used to construct a genetic linkage map of rice. Total of 142 newly screened AFLP markers and 30 anchor markers (25 SSR markers and 5 RFLP markers) were mapped on the 12 chromosomes covering 1537.4 cM of rice genome. The average interval between these markers was 9.0 cM. The total work which usually was finished in more than one year was finished within only 3 months by one person. This is the first plant AFLP map developed in China. A new thermosensitive genic male sterile gene in rice, tms5, was Egged and mapped onto chromosome 2 during the development of the linkage map. 展开更多
关键词 AFLP rapid constructing genetic linkage map rice thermosensitive genic male sterile gene tms5
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Construction of Molecular Genetic Linkage Map Based on an RIL Population of Rice and Detection of QTLs for Tiller Angle 被引量:1
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作者 张亚东 董少玲 +7 位作者 张颖慧 陈涛 赵庆勇 朱镇 周丽慧 姚姝 赵凌 王才林 《Agricultural Science & Technology》 CAS 2013年第5期689-694,共6页
In this study, an RIL (recombinant inbred line) population containing 240 lines was developed by single seed descent method (SSD) based on a parent com- bination of small-grain indica cultivar Kasalath and large-g... In this study, an RIL (recombinant inbred line) population containing 240 lines was developed by single seed descent method (SSD) based on a parent com- bination of small-grain indica cultivar Kasalath and large-grain japanica cultivar TD70 with significant differences in plant type traits, to construct the molecular genetic linkage map. Totally 838 SSR (Simple Sequence Repeat) markers were used for polymorphism screening between parents, 302 SSR markers with polymorphism were detected, with a frequency of 36.04%; 141 SSR markers with clear amplified bands and uniform distribution in the genome were finally used for genotype analysis of the RIL population. According to the experimental results, the frequency of male and female genotype in this RIL population was respectively 53% and 47%, suggesting good balance in population structure. A molecular genetic linkage map of rice was constructed by 141 markers based on a RIL population of 240 lines, with a total genetic distance of about 1 832.47 cM covering all 12 chromosomes, an average genetic distance between markers of 12.70 cM and a range of genetic distance be- tween markers of 0.43-36.11 cM, which is consistent with basic requirements of quantitative trait locus (QTL) mapping. Except for few markers on chromosomes 1 and 8, the order and location of markers is similar to the published sequences of Nipponbare. QTL analysis for the tiller angle was conducted with this RIL population of 240 lines, and results showed that three QTLs controlling tiller angle were detected on chromosome 8, 9 and 11, which were named qTA8, qTA9 and qTA11, with a contribution rate of 4.10%, 26.08% and 4.35%, respectively. To be specific, qTA9 contained Tiller Angle Controlling (TAC1) gene. The construction of this molecular genetic linkage map laid the foundation for genetic analysis and QTL mapping of various traits in the progeny of indica and japonica. 展开更多
关键词 Recombinant inbred line Molecular genetic linkage map Tiller angle QTL SSR
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A Preliminary Study on Conservation Genetics of Three Endangered Orchid Species 被引量:16
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作者 李昂 罗毅波 +1 位作者 熊治廷 葛颂 《Acta Botanica Sinica》 CSCD 2002年第2期250-252,共3页
采用随机扩增多态DNA(RAPD)分析研究了中国 3种珍稀濒危兰科植物硬叶兜兰 (PaphiopedilummicranthumTangetWang)、麻栗坡兜兰 (P .malipoenseS .C .ChenetTsi)和独花兰 (ChangnieniaamoenaChien)的遗传多样性与群体遗传结构。 12个RAPD... 采用随机扩增多态DNA(RAPD)分析研究了中国 3种珍稀濒危兰科植物硬叶兜兰 (PaphiopedilummicranthumTangetWang)、麻栗坡兜兰 (P .malipoenseS .C .ChenetTsi)和独花兰 (ChangnieniaamoenaChien)的遗传多样性与群体遗传结构。 12个RAPD引物在 2种兜兰中共扩增出 131条带。对 4个硬叶兜兰群体的检测表明其物种水平的多态条带百分率 (PPB)为 71.6 % ,Nei的基因多样度 (h)为 0 .2 171,Shannon多样性指数 (I)为 0 .330 1;4个群体的平均多样性水平为PPB =45 .2 % ,h =0 .145 7,I =0 .2 2 0 4,低于远交兰花的平均水平。在总遗传变异中 ,群体间遗传变异占 2 0 .31% ,略高于远交物种的平均水平。在物种水平上 ,麻栗坡兜兰的PPB为 49.5 % ,h为 0 .1174,I为0 .176 4,均大大低于硬叶兜兰。对 11个独花兰群体采用 16个RAPD引物共扩增出 119条带。物种水平PPB =76 .5 % ,h =0 .1941,I=0 .30 5 8;在群体水平上 ,上述 3个指标的平均值则分别为 37.2 %、0 .1197和 0 .1810 ,均低于远交兰花的平均水平。群体间的遗传变异占 45 .2 7% ,遗传分化明显高于远交物种的平均水平。导致 3个物种遗传多样性偏低而群体间遗传分化较高的主要原因在于人为的过度采挖和生境的片断化。 展开更多
关键词 PAPHIOPEDILUM Changnienia amoena RAPDS conservation genetics
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Price linkage between Chinese and international nonferrous metals commodity markets based on VAR-DCC-GARCH models 被引量:16
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作者 岳意定 刘笃池 徐珊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期1020-1026,共7页
Using VAR-DCC-GARCH model,the literature on commodity price was extended by exploring the co-movement between Chinese nonferrous metal prices and global nonferrous metal prices represented by the nonferrous metal pric... Using VAR-DCC-GARCH model,the literature on commodity price was extended by exploring the co-movement between Chinese nonferrous metal prices and global nonferrous metal prices represented by the nonferrous metal prices from London Metal Exchange(LME).The results show that LME nonferrous metals prices still have a greater impact on Chinese nonferrous metals prices.However,the impact of Chinese nonferrous metals prices on LME nonferrous metals prices is still weak except for lead price.The co-movement of nonferrous metal prices between LME and China presents hysteretic nature,and it lasts for 7-8trading days.Furthermore,the co-movement between LME nonferrous metals prices and Chinese nonferrous metals prices has the characteristics of time-varying,and the correlation of lead prices between LME and China is the more stable than all other nonferrous metals prices. 展开更多
关键词 price linkage nonferrous metals commodity prices Chinese metals commodity market LME CO-MOVEMENT VAR model DCC-GARCH model
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k-center问题的算法研究综述
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作者 王晓峰 华盈盈 +2 位作者 王军霞 彭庆媛 何飞 《郑州大学学报(工学版)》 CAS 北大核心 2025年第1期42-50,97,共10页
k-center问题是设施选址的基础问题,同样是NP难问题,在分配、紧急服务等领域也有着实际的应用。随着问题规模的扩大,原有的算法已不再适用,需要进一步优化或者改进。为了找到求解该问题的高效算法,对现有算法进行研究。对各类求解k-cen... k-center问题是设施选址的基础问题,同样是NP难问题,在分配、紧急服务等领域也有着实际的应用。随着问题规模的扩大,原有的算法已不再适用,需要进一步优化或者改进。为了找到求解该问题的高效算法,对现有算法进行研究。对各类求解k-center问题的算法进行梳理,将求解算法划分为精确算法、启发式算法、元启发式算法、近似算法等,从算法原理、改进思路、性能和精度等方面进行对比综述。精确算法在求解小规模k-center问题时可在多项式时间内得到最优解,但是算法效率低,不适用于大规模问题;启发式算法可以在多项式时间内给出相对最优解,但是没有理论保证,无法衡量与最优解的关系;元启发式算法可根据对目前存在的智能优化算法进行改进,给出相对最优解,但是解的质量无法保证;利用近似算法得到的解具有近似比保证,有较大的理论研究价值,但是实用价值较弱。目前求解k-center问题的元启发式算法已取得一定的研究成果,但是在求解时间、求解规模、算法效率等方面仍待突破,这将是未来k-center问题的研究重点。 展开更多
关键词 k-center问题 精确算法 近似算法 蜂群优化 遗传算法
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Genetic Analysis and Linkage Mapping in a Resource Pig Population Using Microsatellite Markers 被引量:1
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作者 张敬虎 熊远著 +5 位作者 左波 雷明刚 蒋思文 李凤娥 郑嵘 李家连 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期10-16,共7页
The use of markers and linkage map construction are important for QTL mapping in pigs. In this article, the genetic characteristics were studied and the linkage map was constructed in a pig resource population includi... The use of markers and linkage map construction are important for QTL mapping in pigs. In this article, the genetic characteristics were studied and the linkage map was constructed in a pig resource population including 214 individuals by typing 39 microsatellite marker loci on Sus scrofa chromosomes, SSC4, SSC6, SSC7, SSC8, and SSC13. Results indicated that the average allele number, the average observed beterozygosity (Ho), and the average polymorphism information content (PIC) in F1 and F2 population were 3.2, 0.528, 0.463 and 3.2, 0.496, 0.447, respectively. In the pig resource population, the average informative meiosis (IM) was 217.4 (44-316), and the average linkage map length between the two sexes on the five chromosomes were 172.3 cM (SSC4), 168.7 cM (SSC6), 191.7 cM (SSC7), 197.3 cM (SSC8), and 178.3 cM (SSC13). The orders of microsatellite marker loci in the linkage maps were identical to, but the length was greater than, those of USDA-MARC reference map. The results of this research showed the genetic relationship and genetic characteristics of the microsatellite markers in the pig resource family population, and the linkage map could be used to for QTL mapping in the subsequent study. 展开更多
关键词 PIG microsatellite marker linkage map HETEROZYGOSITY
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Molecular Genetic Diagnostics of Prader-Willi Syndrome:a Validation of Linkage Analysis for the Chinese Population 被引量:1
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作者 李洪义 孟舒 +8 位作者 陈争 李海飞 杜敏联 马华梅 魏海云 段红蕾 郑辉 闻人庆 宋新明 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第10期885-891,共7页
Prader-Willi Syndrome (PWS) is a genetic disorder that is difficult to detect, particularly at an early age. PWS is caused by disruption of normal, epigenetically controlled gene function in the chromosome 15q11-q13... Prader-Willi Syndrome (PWS) is a genetic disorder that is difficult to detect, particularly at an early age. PWS is caused by disruption of normal, epigenetically controlled gene function in the chromosome 15q11-q13 region. Clinical symptoms are difficult to diagnose in infants and only become clearer at later ages as the patients develop hyperphagia and morbid obesity. Molecular genetic tests are able to definitively diagnose PWS and allow early diagnosis of the syndrome. High resolution cytogenetic testing, methylation-specific PCR (MS-PCR), and linkage analysis are routinely used to diagnose PWS. To establish a linkage analysis method for Chinese patients, this study identified a useful set of STR markers in the typical PWS deletion and adjacent area, for linkage analysis in two Chinese families with PWS offspring. Using this method, the authors confn'rned that one patient had a paternal deletion in chromosome 15q 11-q 13 and the other patient had maternal uniparental heterodisomy of chromosome 15. MS -PCR and high resolution chromosome G-banding also confirmed this diagnosis. This linkage analysis method can detect both deletion and uniparental disomy, thus providing valuable information for genetic counseling and the opportunity to analyze the relationship between the genotype and phenotype of PWS. 展开更多
关键词 Prader-Willi Syndrome uniparental disomy OBESITY genomic imprinting linkage analysis
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Elimination Mechanism and Equilibrium Model about Complete Linkage of Panmixis Based on Fitness 被引量:2
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作者 覃俊达 陈奇 李大林 《Agricultural Science & Technology》 CAS 2011年第6期801-804,共4页
[Objective]The aim was to discuss elimination mechanism and equilibrium model about complete linkage gene of panmixis based on fitness.[Method]A mathematical model that gsgenerational evalution of frequency of panmixi... [Objective]The aim was to discuss elimination mechanism and equilibrium model about complete linkage gene of panmixis based on fitness.[Method]A mathematical model that gsgenerational evalution of frequency of panmixis two pairs of complete linkage gene under difference fitness was built by using difference equations to study elimination mechanism and genetic equilibrium state of panncticcoinplete linkage gene.[Result]The panmixis is different from Hardy-Weinberg Equilibrium which reached the equilibrium just by one generation.A method that by using linear equation to calculate the frequency of four gametes and the fitnessed of panmixis was established after detormining is the fitness of 10 genotypes the necessary and sufficient condition of the panmixis to reach balance.[Conclusion]The method is valuable for reference on linkage disequilibrium and hitchhiking effect study. 展开更多
关键词 Random match Complete linkage Gene frequency FITNESS EQUILIBRIUM
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