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Journal of Integrative Plant Biology 2006年第10期48卷 1140-1146页

作者： Meng Xiao Qun Li Li Wang Liang Guo Jing Li Lin Tang Fang Chen College of Life Sciences Sichuan University Chengdu 610064 China sichuan Agricultural Management College Chengdu 610071 China

Slnopodophyllum hexandrum （Royle） Ying Is an Important medicinal and endangered species. Inter-simple sequence repeats （ISSR） analysis was conducted on seven natural populations from western Slchuan Province to Investigate the genetic diversity of S. hexandrum. Leaf samples of 140 Individuals were collected. Of the 139 discernible fragments generated by 12 selected primers （among 100 primers）, 54 appeared to be polymorphlc. The percentage of polymorphlc bands （PPB） was 38.85% at the species level, and PPB within a population ranged from 7.91% to 23.74%. Low levels of genetic variation （He = 0.092, Ho = 0.142） and high levels of genetic differentiation among the populations （Gst= 62.25%） was detected on the basis of results from POPGENE and analysis of molecular variance （AMOVA）, respectively. Furthermore, the limited gene flow （Nm = 0.361） may result from biological characteristics, such as self-pollination and short distance seed dispersal. Based on the genetic and ecological Information available for S. hexandrum, we propose some appropriate strategies for the conservation of the endangered medicinal species in this region, namely rescuing and conserving the core populations for in situ conservation and sampling and preserving more populations with fewer Individuals from each population for ex situ conservation.

关键词： conservation genetic diversity inter-simple sequence repeat (ISSR) Sinopodophyllum hexandrum

A Case Study of Applying Metagenomic Sequencing in Precise Epidemiology for the COVID-19 Pandemic-sichuan Province, China, 2020

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China CDC weekly 2020年第47期2卷 897-901页

作者： Jianan Xu Ye Wang You Li Huiping Yang Ming Pan Jian Liu Lina Shi Yuliang Feng Li Liu Jin Li Li Zhang Shusen He sichuan Provincial Center for Disease Control and Prevention ChengduSichuanChina HitGen Inc. ChengduSichuanChina sichuan Key Laboratory of Conservation Biology on Endangered Wildlife Chengdu Research Base of Giant Panda BreedingChengduSichuanChina

Introduction:Determining the transmission chain of a virus in its incipient stages is extremely time consuming in traditional approaches that rely mainly on case incidence and interview-based contact *** the development of high-throughput sequencing technology,genome-based epidemiology approach is showing promise in detecting viral ***,there is still insufficient evidence for the relationship between the viral genetic variations and real viral ***:To explore the possible relationship between transmission chains and viral genetic variations,we combined both epidemiological data and viral genomes of COVID-19 virus collected from sichuan Province.A phylogenetic approach was used to infer the transmission chain,which was then compared to the transmission chain that came from epidemiological ***:We found that the putative transmission chains were highly concordant to the true transmission chains from epidemiological data,suggesting a strong correlation between viral genetic variations and the viral transmission ***:Our results showed advantages of viral genomic sequencing in tracking and perceiving pathogen transmission,which allowed for potential improvements in the design and implementation of population-level public health interventions.

关键词： chains interview consuming

Management Philosophy and Practices of Habitat Conservation for Jiuzhaigou Nature Reserve, sichuan, China

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Wuhan university Journal of Natural Sciences 2005年第4期10卷 730-738页

作者： FANGYi-ping ZENGYong LIShi-ming SchoolofManagement UniversityofElectronicScienceandTechnologyChengdu610054SichuanChina／／InstituteofMountainHazardsandEnvironmentChineseAcademyofSciencesChengdu610041SichuanChina SchoolofManagement UniversityofElectronicScienceandTechnologyChengdu610054SichuanChina

Starting from the pressure on habitat of Jiuzhaigou Nature Reserve broughtabout by traveling activity, this paper puts forward such philosophy of community co-management ofconservation-based tourism development for Jiuzhaigou Nature Reserve. According to this philosophy,emphasis is laid on the analysis of the mission of habitat protection, functional division, habitatmaintenance, community construction, scientific study and management organization system. The studyshows that the close relation and significance of rights and interests shared between nature reserveand residents in community, as well as the value of community co-management philosophy ofconservation-based tourism development in sustainable management of nature reserve, have set anexemplary example for other nature reserves.

关键词： Jiuzhaigou Nature Reserve philosophy of habitat management conservation-based development community co-management

Initial Study on sichuan Apomixis Rice (SAR-1)

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Science China Chemistry 1993年第4期36卷 420-429页

作者：周开达汪旭东罗明高克明周绍莉严志彬李平陈放周桂梅 Rice Research Institute of sichuan Agricultural university Wenjiang 611130 PRC Department of Biology Sichuan University Chengdu 610064 PRC

SAR-1 is a new germplasm which was discovered in the breeding material of southern multiplication in spring, 1988. The material showing high sterility of pollens is able to set seeds spontaneously. Under isolation, the seed-setting highest rate may reach 55.33%. The florets emasculated by clipping spikelet and lukewarm water still set seeds at certain rates. The completely sterile florets, after being emasculated and checked under microscope one by one, still set seeds, and the highest setting rate is 41.80%. Cytoembryological research indicates that the egg of SAR-1, without fertilization, divides independently into an embryo, which follows the normal process to maturity. Adventitious embryos originate from ovary wall cells. Therefore, it is deduced that SAR-1 has multiple mechanisms of apomixis, and the unfertilized polar nuclei fuse and develop into endosperm cells. The endosperm provids the embryo with nutrient for development. The automatic formation of the endosperm is an obvious feature of SAR-1.

关键词： rice apomixis embryology.

Comparative study of bacterial status from conjunctival sac of the elder Qiang minority and Han people with dry eye in sichuan,China

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International Journal of Ophthalmology(English edition) 2012年第3期5卷 343-347页

作者： Yue Zhang, Kui Cao Department of Ophthalmology Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital Chengdu 610072 Sichuan Province China Mianyang Wanjiang Ophthalmologic Hospital Mianyang 621000 Sichuan Province China Department of Clinical Laboratory Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital Chengdu 610072 Sichuan Province China Hospital of Traditional Chinese Medclicine Affiliated to Luzhou Medical College Luzhou 646000 Sichuan ProvinceChina The Fourth People's Hospital of Zigong City. Zigong 643000 Sichuan Province China

AIM: To compare the status of bacteria in the conjunctival sac from the elder Qiang minority and Han people with dry eyes in sichuan, China. METHODS: Total of 54 elder Qiang people with dry eyes (108 eyes) were examined by cluster sampling. In the similar habitation region of Han people, 80 (160 dry eyes) Han people were analyzed as the control group. The bacteria was separated from the inferior palpebral conjunctiva, then inoculated on blood plate for 48 hours and identified. RESULTS: Totally 24 strains of bacteria were cultured in either Qiang minority or Han c populations with 3 strains of them existed in both ethnic groups. The commonest bacteria in conjunctival sac in two ethnic groups were non-pathogenic bacterium. The composition of Corynebacterium in Han people (54.1%) was significantly higher than that in Qiang minority (27.4%) (chi(2)=11.6721, P=0.0006). The percentage of Sphingomonas Paucimobilis in Qiang people was higher than that in Han people (chi(2)=18.6442, P=0.0000). However, there was no significant difference between Qiang minority and Han people either in bacterial positive rate in conjunctival sac, or the composition of bacteria species and strains, or the composition of staphylococcus epidemids between two ethnic populations. CONCLUSION:There was no significant difference of bacterial positive rate in conjunctival sac from the elder of Qiang minority and Han people with dry eye, but the species of bacteria were different.

关键词： conjunctival sac bacteria dry eye

Projecting the Dynamic Trends of Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome:Modeling the Epidemic in sichuan Province, China

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Biomedical and Environmental Sciences 2024年第9期37卷 1003-1014页

作者： Yuan Li Qinxi Liu Rongsheng Luan Yi Yang Tao Wu Bihui Yang West China School of Public Health&No.4 West China Teaching Hospital Sichuan UniversityChengdu 610041SichuanChina Chengdu university of Traditional Chinese Medicine Chengdu 611137SichuanChina

Objective Our study aimed to provide a comprehensive overview of the current status and dynamic trends of the human immunodeficiency virus(HIV)prevalence in sichuan,the second most heavily affected province in China,and to explore future *** The epidemiological,behavioral,and population census data from multiple sources were analyzed to extract inputs for an acquired immunodeficiency syndrome(AIDS)epidemic model(AEM).Baseline curves,derived from historical trends in HIV prevalence,were used,and the AEM was employed to examine future intervention *** In 2015,the modeled data suggested an adult HIV prevalence of 0.191%in sichuan,with an estimated 128,766 people living with HIV/AIDS and 16,983 individuals with newly diagnosed *** current high-risk behaviors,the model predicts an increase in the adult prevalence to 0.306%by 2025,projecting an estimated 212,168 people living with HIV/AIDS and 16,555 individuals with newly diagnosed *** Heterosexual transmission will likely emerge as the primary mode of AIDS transmission in ***,we anticipate a stabilization in the incidence of AIDS with a concurrent increase in *** comprehensive intervention measures aimed at high-risk groups could effectively alleviate the spread of AIDS in sichuan.

关键词： HIV/AIDS AIDS Epidemic Model Heterosexual transmission sichuan province

Origin and controlling factors of chlorite coatings—an example from the reservoir of T_3x Group of the Baojie area,sichuan Basin,China

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Petroleum Science 2009年第4期6卷 376-382页

作者： Peng Jun1,Liu Jinku2,Wang Yan2 and Liu Jianfeng2 1 Scientific Research Department,Southwest Petroleum university,Chengdu,sichuan 610500,China 2 Graduate School,Southwest Petroleum university,Chengdu,sichuan 610500,China Scientific Research Department Southwest Petroleum University Chengdu Sichuan China Graduate School Southwest Petroleum University Chengdu Sichuan China

The study of the chlorite coatings always attracts scholars in China and other countries because the chlorite coatings play an important role in the preservation of residual primary pores in sandstone *** present,the study of the origin and the controlling factors is relatively *** occurrence,time of formation,genesis,controlling factors,and the mechanism of chlorite coatings inhibiting quartz overgrowths were studied in detail with thin section and SEM *** were from the sandstone reservoirs of the T3x Group in the Baojie area,the transitional zone from the middle to the south of sichuan *** results indicate that the chlorite coatings on the walls of the pore spaces are oriented perpendicular to grain surfaces in the form of isopachous(even-thickness) grain-coating,while the chlorite coatings at the contacts between adjacent detrital grains are arranged with a preferred orientation tangential to the surface of detrital *** chlorite coatings were formed in the eogenetic *** were formed by recrystallization of Fe-rich clay films during the syndepositional period,and chlorite cements would be recrystallized after the coatings’ *** formation of chlorite coatings was mainly controlled by the depositional environment,provenance conditions,and diagenetic *** presence of chlorite coatings could result in the preservation of primary pores in deeply buried sandstone reservoirs by effectively inhibiting quartz overgrowths and the development of compaction and pressure solution.

关键词： Chlorite coatings occurrence time of formation origin controlling factor quartz overgrowths T3x Group

Petrophysical and capillary pressure properties of the upper Triassic Xujiahe Formation tight gas sandstones in western sichuan,China

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Petroleum Science 2011年第1期8卷 34-42页

作者： Ye Sujuan Lu Zhengxiang Li Rong Exploration and Production Research Institute Sinopec Southwest CompanySichuan 610081China Chengdu Institute of Geology and Mineral Resources Sichuan 610081China

The tight sandstones of the Upper Triassic Xujiahe Formation（T_3x） constitute important gas reservoirs in western *** Xujiahe sandstones are characterized by low to very low porosity （av.5.22%and 3.62%） for the T_3x^4 and T_3x^2 sandstones,respectively）,extremely low permeability（av. 0.060 mD and 0.058 mD for the T_3x^4 and T_3x^2 sandstones,respectively）,strong heterogeneity,micronano pore throat,and poor pore throat *** a result of complex pore structure and the occurrence of fractures,weak correlations exist between petrophysical properties and pore throat size,demonstrating that porosity or pore throat size alone does not serve as a good permeability *** improved correlations can be obtained between permeability and porosity when pore throat radii are incorporated. Correlations between porosity,permeability,and pore throat radii corresponding to different saturations of mercury were established,showing that the pore throat radius at 20%mercury saturation（R_（20）） is the best permeability *** regression analysis and artificial neural network（ANN） methods were used to establish permeability prediction models and the unique characteristics of neural networks enable them to be more successful in predicting permeability than the multivariate regression *** addition, four petrophysical rock types can be identified based on the distributions of R_（20）,each exhibiting distinct petrophysical properties and corresponding to different flow units.

关键词： Western sichuan upper Triassic Xujiahe Formation tight sandstones permeability porosity pore throat radius regression analysis artificial neural network

Effect of Particle Size and Distribution of Rapidly Quenching NdFeB Magnetic Powder on Magnetic Properties of Polymer-Bonded NdFeB Permanent Magnet

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Journal of Rare Earths 1999年第2期17卷 40-42页

作者： Liu, Ying Tu, Mingjing sichuan univ Chengdu China

The effect of particle size and distribution of rapidly quenching NdFeB magnetic powder on the magnetic properties of polymerbonded NdFeB permanent magnet was studied. The results show that the particle size and the distribution of rapidly quenching NdFeB magnetic powder have significant effects on the magnetic properties of polymerbonded NdFeB permanent magnet. As long as the size and the distribution of rapidly quenching NdFeB powder are within the right range, high magnetic properties of polymerbonded NdFeB permanent magnet can be obtained. This is mainly because the rapidly quenching NdFeB magnetic powder has high hardness and is scaleshaped. The larger the size of rapidly quenching NdFeB particles is, the more difficult it is to obtain high density of bonded NdFeB magnet. However the structure will be destroyed if the size is too small. It results in the deterioration of magnetic properties. The mechanism is also discussed.

关键词： Rare earths NdFeB powder Particle size Particle distribution Magnetic properties

A New Sauropod, Gongxianosaurus, from the Lower Jurassic of sichuan, China

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 132-136页

作者： LUO Yaonan WANG Changsheng sichuan Bureau of Geology and Mineral Exploration and Development Chengdu Sichuan 610081 Yuzhou university Chongqing 400033

The paper describes an early and primitive sauropod dinosaur, Gongxianosaurus shibeiensis (gen. et sp. nov.), from the Dongyuemiao Member of the Lower Jurassic Ziliujing Formation in Shibei Township, Gongxian County, sichuan Province, China, which is one of the 5 dinosaur fossils discovered in Gongxian in 1997. Except the skull which is incomplete, the fossils are well preserved. It has some features of both sauropods and prosauropods. It is an intermediate type in the evolution of dinosaurs from prosauropods to sauropods and provides materials for the study of the origin and evolution of the sauropod dinosaur fauna. The discovery of this new sauropod furnishes a way for the stratigraphic correlation between the Early Jurassic Ziliujing Formation in the sichuan basin and the Lower Jurassic Lufeng Formation in the Central Yunnan basin.

关键词： Early Jurassic Dongyuemiao Member sauropod Gongxianosaurus shibeiensis(gen.et sp.nov.)