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| 1 | On Palaeozoic Tectonics in the Alxa Region, Inner Mongolia, China显示文摘Two ophiolitic melange belts in the Late Carboniferous formations have been discovered recently in the Alxa region. One is in the Engger Us fault and possesses properties of oceanic crust. The other is in the Badain Jaran fault and shows properties of a back-arc basin. These two faults, together with the Yagan fault, constitute the important boundaries of tectonic units in the Alax region. The four tectonic units delimited by these faults are different in rock assemblages, metamorphism and geochemistry. They reflect the nature of tectonic environments in which they are found. The tectonic units may be traced and correlated to the eastern and western neighbouring areas. The formation and evolution process of the units and their interaction in the Alxa region may be described in terms of the evolution of the Palaeo-Mongolian Ocean and its continental margins. | WU Tairan HE Guoqi ZHANG Chen | 1998 | Acta Geologica Sinica(English Edition)1998，72，3： | 28 |
| 2 | Effects of dietary alfalfa flavonoids extraction on growth performance,organ development and blood biochemical indexes of Yangzhou geese aged from 28 to 70 days显示文摘This experiment was conducted to study the effects of dietary alfalfa flavonoids extraction supplemental level on growth performance, organ development and blood biochemical indexes of Yangzhou geese at the age of 28 to 70 days. Two hundred and forty 21-day-old healthy male geese with similar body weight were randomly distributed into 4 groups with 6 replicates per group and 10 geese per replicate. Geese in the control group were fed a basal diet and the others in the experimental groups(groups 1,2, and 3) were fed experimental diets supplemented with 150, 300 and 450 mg/kg alfalfa flavonoids extraction(the concentration of it was 81%), respectively. The experiment had 7 days for pre-test and 42 days for formal test.The results showed that the final body weight and average daily intake of group 2 were significantly higher than those of other groups(P < 0.05). The average daily gain of group 2 was significantly higher than that in the control group and group 1(P < 0.05). There was no significant difference in feed-to-gain ratio between each group(P > 0.05). Pre-slaughter live weight, carcass weight, slaughter rate, semieviscerated weight, semi-eviscerated rate, eviscerated weight, eviscerated rate, leg muscle weight and leg muscle rate had no significant difference between each group(P > 0.05). The breast muscle weight and ratio of each test group were significantly higher than those in the control group(P < 0.05) and the group2 was the best. The abdominal fat weight and ratio in the group 1 were significantly higher than those in the control group and group 3(P < 0.05) and the tibia weight in the group 2 was significantly higher than that in the control group and group 1(P < 0.05); There were no significant differences in heart weight,liver weight and the gland stomach weight among all groups(P > 0.05). Spleen weight in test groups was significantly higher than that in the control group(P < 0.05). The bursa weight and muscular stomach weight in the group 2 were significantly higher than those in the control group and group 1(P < 0.05). In serum, total cholesterol, triglycerides, low-density lipoprotein and urea nitrogen in the group 2 were significantly lower comparing with those in the control group(P < 0.05). High-density lipoprotein in the group 2 was significantly higher than that in other groups(P < 0.05). There were no significant differences in total serum protein, albumin, globulin and albumin/globulin among all groups(P > 0.05). Alanine aminotransferase and aspartate transaminase(AST) in groups 2 and 3 were higher than those in the group1 and control group but not obvious(P > 0.05) and alkaline phosphatase(ALP) in groups 1 and 2 was higher than that in the control group and group 3(P > 0.05). It is concluded that alfalfa flavonoids extraction added in dietary feed improve the growth performance, organ development and blood biochemical indexes of Yangzhou geese. It is concluded that 300 mg/kg supplemental level of the dietary alfalfa flavonoids extraction is optimal in this experiment. | Yinyin Chen Xiaoxiao Gong Guodong Li Miao Lin Yongjiu Huo Shengli Li Guoqi Zhao | 2016 | Animal Nutrition2016，，4： | 14 |
| 3 | Location characteristics and differentiation mechanism of logistics nodes and logistics enterprises based on points of interest (POI): A case study of Beijing显示文摘后勤节点和后勤企业是核心搬运人和后勤空间的组织上的题目,并且他们的地点特征和区别策略具有到优化城市的后勤的关键重要性空间模式和保证合理资源分配。从 2014 年 12 月基于 Tencent 联机地图站台,兴趣(夏威夷人用芋头做成的食品) 的 4396 个后勤点在中国北京被收集。由工业集中评估和核密度分析的方法,在北京的后勤的空间分发模式被探索,在类型差别,供应要求方面因素和地点选择行为之中的相互作用机制被澄清,并且在交通的联合影响下面的空间区别的内部机制,陆地租金和财产被揭示。下列结论在纸被得出。(1 ) 后勤企业和后勤节点在地点展出合作凝块和空间分离的特征,并且后勤活动显示“闹市区区域,郊区和城市远郊的区域的边缘的区域”的空间模式,它与后勤雇用空格有弱联合度。(2 ) 也就是,后勤停的公共后勤空间和后勤集中,在政府的指导下面被生产,并且由后勤分发组成的终端后勤空间集中服务因为特定的工业和终端用户被企业统治。在后勤空间的二个模式之间的位置上的区别是重要的。( 3 )在后勤的形成空间地点,政府能由重新计划改变交通条件运输线路和运费驻扎地点,并且由增加或减少控制陆地租金和不同区域的可获得性后勤的陆地使用,影响企业行为并且形成后勤空格和函数区别的不同类型。在比较,后勤企业通过财产分配的区别遇见服务目标的多样的要求支持分割的专门化并且形成后勤空间的目标区别。 | LI Guoqi JIN Fengjun CHEN Yu JIAO Jinjuan LIU Sijing | 2017 | Journal of Geographical Sciences2017，27，7： | 11 |
| 4 | Mechanical Properties of Methane Hydrate-Bearing Interlayered Sediments显示文摘The complex distribution of gas hydrate in sediments makes understanding the mechanical properties of hydrate-bearing sediments a challenging task.The mechanical behaviors of hydrate-bearing interlayered sediments are still poorly known.A series of triaxial shearing tests were conducted to investigate the strength parameters and deformation properties of methane hydrate-bearing interlayered sediments at the effective pressure of 1 MPa.The results indicate that the stress-strain curves of hydrate-bearing interlayered sediments are significantly different from that of hydrate-bearing sediments.The peak strength,Young's modulus,initial yielding modulus,and failure mode are deeply affected by the methane hydrate distribution.The failure behaviors and mechanism of strain softening and hardening patterns of the interlayered specimens are more complicated than those of the integrated specimens.This study compares the different mechanical behaviors between integrated and interlayered specimens containing gas hydrate,which can serve as a reference for the prediction and analysis of the deformation behaviors of natural gas hydrate reservoirs. | DONG Lin LI Yanlong LIU Changling LIAO Hualin CHEN Guoqi CHEN Qiang LIU Lele HU Gaowei | 2019 | Journal of Ocean University of China2019，18，6： | 11 |
| 5 | Silurian to Devonian foreland basin in the south edge of Tarim Basin显示文摘Based on the theory of plate tectonics, combin-ing with the isotopic dating of ophiolite, igneous and volcan-ics, geochemical test, rare earth element analyze and seismicinterpretation, this paper studies the pre-Carboniferous tec-tonics and sedimentary formation of the south edge of theTarim Basin and proves that there exists the Kunlun Oceanunder tensional tectonics during the Sinian and Cambrian inthe south edge of the Tarim Plate. After that, due to the colli-sion orogenesis, there formed the peripheral foreland basinin the south edge of Tarim. The Upper Silurian and Devo-nian molasses sedimentary system superposed on the Sinianand Middle Silurian passive margin flysch sedimentary sys-tem and formed the bivariate structure of the foreland basin.And at the same time, based on the field geology and seismicinterpretation, we have identified that the formation of theSilurian and Devonian have the character of half depositwhich shows thick in the south area and thin in the north,and the pre-Carboniferous thrust compression tectonics re-mained in the foreland thrust belt, which further demon-strates that there existed the Silurian and Devonian periph-eral foreland basin on the south edge of the Tarim Basin. | WEI Guoqi JIA Chengzao LI Benliang CHEN Hanlin | 2002 | Chinese Science Bulletin2002，47，S1： | 10 |
| 6 | Meso-Cenozoic Tectonic Events Recorded by Apatite Fission Track in the Northern Longmen-Micang Mountains Region显示文摘There is a cross-cutting relationship between the E-W trending structures and the NE-trending structures in the northern Longmen-Micang Mountains region,which reflects possible regional tectonic transition and migration.Apatite fission track(AFT) analyses of 15 samples collected from this area yield apparent ages varying from 30.3±4.2 Ma to 111.7±9.0 Ma and confined-track-lengths ranging from 10.6±0.3 μm to 12.4±0.1 μm.Four specific groups were identified on the basis of the Track Age Spectrum Calculation(TASC) patterns,i.e.,143-112Ma,93.6-88?Ma,42-40Ma and ~25.6Ma.These age groups correspond to the spatial distributions of datasets and may represent four tectonic events.Together with the regional deformation patterns,the four age groups are interpreted to indicate tectonic superposition,transition and migration during the Meso-Cenozoic with the following possible order:(1) the Micang Mountains belt was dominated by the E-W trending structure during 143-112Ma;(2) the contraction of the Longmen Mountains belt from the NW to the SE during 93.6-88Ma led to the superposition of the NE-trending structures over the E-W trendinding structures;(3) dextral strike-slip shear dominated the Longmen Mountains belt at 42-40Ma;(4) westward migration of the active tectonic belt occurred from 93.6-25.6Ma in a break-back sequence in the northern Longmen Mountains belt.The Late Cenozoic tectonics in the northern Longmen Mountains belt are characterized by the dextral strike-slip shear and the occurrence of westward break-back sequence of deformations.As a result,north-south differences in deformations along the Longmen Mountains belt were intensified since the Miocene time and strains were mainly accumulated in the hinterland of the Longmen Mountains instead of being propagated to the foreland basin. | LEI Yongliang JIA Chengzao LI Benliang WEI Guoqi CHEN Zhuxin SHI Xin | 2012 | Acta Geologica Sinica(English Edition)2012，86，1： | 8 |
| 7 | Comparative Study of ROCK1 and ROCK2 in Hippocampal Spine Formation and Synaptic Function显示文摘Rho-associated kinases(ROCKs)are serinethreonine protein kinases that act downstream of small Rho GTPases to regulate the dynamics of the actin cytoskeleton.Two ROCK isoforms(ROCK1 and ROCK2)are expressed in the mammalian central nervous system.Although ROCK activity has been implicated in synapse formation,whether the distinct ROCK isoforms have different roles in synapse formation and function in vivo is not clear.Here,we used a genetic approach to address this long-standing question.Both Rock1^+/- and Rock2^+/- mice had impaired glutamatergic transmission,reduced spine density,and fewer excitatory synapses in hippocampal CA1 pyramidal neurons.In addition,both Rockl^+/- and Rock2^+/- mice showed deficits in long-term potentiation at hippocampal CA1 synapses and were impaired in spatial learning and memory based on the water maze and contextual fear conditioning tests.However,the spine morphology of CA1 pyramidal neurons was altered only in Rock2^+/- but not Rock1^+/- mice.In this study we compared the roles of ROCK1 and ROCK2 in synapse formation and function in vivo for the first time.Our results provide a better understanding of the functions of distinct ROCK isoforms in synapse formation and function. | Jinglan Yan Youcan Pan Xiaoyan Zheng Chuanan Zhu Yu Zhang Guoqi Shi Lin Yao Yongjun Chen Nenggui Xu | 2019 | Neuroscience Bulletin2019，35，4： | 7 |
| 8 | Tectonic evolution of Tethyan tectonic field, formation of Northern Margin basin and explorative perspective of natural gas in Tarim Basin显示文摘Analyzing the characteristics of the Tethyantectonic field, the authors think that the Tethyan tectonicfield underwent three evolutional stages: closing of Pa-leo-Tethys and rifting of Neo-Tethys from early Permian tolate Triassic, subduction of Neo-Tethys and collision betweenthe Indian plate and the Eurasia plate from Jurassic to earlyof low Tertiary, and collision between the Arab plate and theEurasia plate and the A-type subduction of Indian plate fromlate of low Tertiary to the present. Combining the evolutionof the Tethyan orogenic belt with the characteristics of theNorthern Margin basin, it is suggested that the sedimentaryand tectonic characteristics and types of the Northern Mar-gin basin are controlled by the formation and evolution ofthe Tethyan orogenic belt and the ingression of Tethys. Theevolution of Northern Margin basin can be divided into threedevelopment stages: back-arc foreland basin from late Per-mian to Triassic, the back-arc fault subsidence and depres-sion from Jurassic to the early of low Tertiary, and the reac-tive foreland basin from the late of low Tertiary to the pre-sent. The Northern Margin basin in the Tethyan tectonicfield is an important region for natural gas accumulation,and the Tarim Basin is a part of this region. | YANG Shufeng JIA Chengzao CHEN HanlinWEI Guoqi CHENG Xiaogan JIA Dong XIAO Ancheng GUO Shaojie | 2002 | Chinese Science Bulletin2002，47，S1： | 7 |
| 9 | Differential expression, molecular cloning,and characterization of porcine beta defensin 114显示文摘Background:β-defensins have attracted considerable research interest because of their roles in protecting hosts from various pathogens.This study was conducted to investigate the expression profiles of the porcineβ-defensin114(PBD114)in different breeds and in response to infections.Moreover,the function of PBD114 protein was partially investigated.Methods:Six Tibetan pigs(TP)and six DLY(Duroc×Landrace×Yorkshire)pigs were slaughtered to explore the expression profiles of PBD114 in different breeds and tissues.For infection models,sixteen DLY pigs were divided into two groups and challenged either with sterile saline or E.coli K88.The recombinant protein PBD114(r PBD114)was obtained by using a heterologous expression system in E.coli.Results:PBD114 gene was highly expressed in tissues such as the intestine,liver,spleen,and thymus.Interestingly,the expression level of PBD114 gene was higher in the TP pigs than in the DLY pigs(P<0.05),and was significantly elevated upon E.coli K88 challenge(P<0.05).The nucleotide sequences of PBD114 from Tibetan and DLY pigs was identical,and both showed a 210-bp open reading frame encoding a 69-amino acid mature peptide.To explaore the function of PBD114 protein,PBD114 gene was successfully expressed in E.coli Origami B(DE3)and the molecular weight of the r PBD114 was estimated by SDS-PAGE to be 25 k Da.The r PBD114 was purified and mass spectrometry verified the protein as PBD114.Importantly,r PBD114 showed antimicrobial activities against E.coli DH5αand E.coli K88,and the minimal inhibitory concentrations(MICs)were 64 and 128μg/m L,respectively.Hemolytic and cytotoxicity assays showed that r PBD114 did not affect cell viability under physiological concentrations.Conclusions:PBD114 is an infection response gene that is differentially-expressed between different porcine breeds and tissues.The antimicrobial activity of PBD114 protein,against pathogens such as the E.coli K88,suggested that it may serve as a candidate for the substitution of conventionally used antibiotics. | Guoqi Su Kunhong Xie Daiwen Chen Bing Yu Zhiqing Huang Yuheng Luo Xiangbing Mao Ping Zheng Jie Yu Junqiu Luo Jun He | 2019 | Journal of Animal Science and Biotechnology2019，10，4： | 4 |
| 10 | Characteristics and Genetic Mechanisms of Overpressure in the Depressions of Bohai Bay Basin, China显示文摘The distribution and genetic mechanisms of abnormal pressures in the Bohai Bay Basin were systematically analyzed. Abnormal pressures are widely developed in the Bohai Bay Basin,primarily in the Paleogene E_(2s_4),E_(2s_3),E_(s_1),and Ed formations. From the onshore area of the Bohai Bay Basin to the center of the Bozhong area,the top depth of the overpressured zone in each depression increases gradually,the overpressured strata in each depression gradually move to younger formations,and the pressure structure successively alters from single-bottom- overpressure to doublebottom-overpressure and finally to double-top-overpressure. The distribution of overpressured area is consistent with the sedimentary migration controlled by the tectonic evolution of the Bohai Bay Basin,which is closely related to the hydrocarbon-generation capability of active source rocks. The overpressured strata are consistent with the source-rock intervals in each depression; the top of the overpressured zone is synchronous with the hydrocarbon generation threshold in each depression; the hydrocarbon generation capability is positively correlated with the overpressure magnitude in each formation. Undercompaction was the main mechanism of overpressure for depressions with fluid pressure coefficients less than 1.2,whereas hydrocarbon generation was the main mechanism for depressions with fluid pressure coefficients greater than 1.5. | LIU Hua JING Chen JIANG Youlu SONG Guoqi YU Qianqian FENG Yuelin | 2016 | Acta Geologica Sinica(English Edition)2016，90，6： | 4 |
| 11 | The protective roles of tea tree oil extracts in bovine mammary epithelial cells and polymorphonuclear leukocytes显示文摘Background: Tea tree oil(TTO) plays an important role in antibacterial activity and alleviating the inflammatory responses. Bovine mammary epithelium and polymorphonuclear leukocytes(PMNL) can actively respond to bovine mastitis infection. However, regulatory effects of TTO extracts on the innate immune response of bovine mammary epithelial cells(BMECs) and PMNL remain not reported. Therefore, aim of the study was to evaluate the effects of TTO extracts on the m RNA levels of the genes involved in the innate immune response of BMECs and PMNL.Results: Our results demonstrated that addition of 0.025% and 0.05% TTO increased the proliferation of BMECs, and significantly enhanced(P < 0.05) the viability of BMECs exposed to Staphylococcus aureus(S. aureus). An inhibitory effect was observed against the growth of S. aureus by TTO incubation. The 0.05% TTO reduced S. aureus biofilm formation, association and invasion of S. aureus to BMECs, and changed the morphological and structural features of S. aureus. The proinflammatory cytokines IL-1β, IL-6, and TNF-α were decreased(P < 0.001) by the incubation of TTO. Interestingly, the expression of IL-8 known for PMNL chemotactic function was elevated(P < 0.05) by 0.05%TTO treatment. Consistently, 0.05% TTO increased the migration of PMNL in S. aureus-exposed BMECs when compared with S. aureus treatment alone(P < 0.05). In addition, PMNL incubated with 0.05% TTO decreased the levels of NFKB inhibitor alpha(NFKBIA) and TNF-α.Conclusions: Our results indicate that use of TTO can relieve the BMECs pro-inflammatory response caused by S.aureus and promote the migration of PMNL to mount the innate immune responses, and it may be novel strategy for the treatment of bovine mastitis caused by S. aureus. | Kang Zhan Tianyu Yang Baobao Feng Xinyu Zhu Yinyin Chen Yongjiu Huo Guoqi Zhao | 2020 | Journal of Animal Science and Biotechnology2020，11，4： | 3 |
| 12 | Systematic reviews on reports of hip fractures in Web of Science:a bibliometric analysis of publication activity显示文摘 | Mao Zhi Wang Guoqi Mei Xifan Chen Shuo Liu Xiaoxie Zeng Xiantao Long Anhua Zhang Licheng Zhang Lihai Tang Peifu | 2014 | Chinese Medical Journal2014，，13： | 2 |
| 13 | Identification of massive molecular markers in Echinochloa phyllopogon using a restriction-site associated DNA approach显示文摘Echinochloa phyllopogon proliferation seriously threatens rice production worldwide. We combined a restriction-site associated DNA(RAD) approach with Illumina DNA sequencing for rapid and mass discovery of simple sequence repeat(SSR) and single nucleotide polymorphism(SNP) markers for E. phyllopogon. RAD tags were generated from the genomic DNA of two E. phyllopogon plants, and sequenced to produce 5197.7 Mb and 5242.9 Mb high quality sequences, respectively. The GC content of E. phyllopogon was 45.8%, which is high for monocots. In total, 4710 putative SSRs were identified in 4132 contigs, which permitted the design of PCR primers for E. phyllopogon. Most repeat motifs among the SSRs identified were dinucleotide(>82%), and most of these SSRs were four motif-repeats(>75%). The most frequent motif was AT, accounting for 36.3%-37.2%, followed by AG and AC. In total, 78 putative polymorphic SSR loci were found. A total of 49,179 SNPs were discovered between the two samples of E. phyllopogon, 67.1% of which were transversions and 32.9% were transitions. We used eight SSRs to study the genetic diversity of four E. phyllopogon populations collected from rice fields in China and all eight loci tested were polymorphic. | Guoqi Chen Wei Zhang Jiapeng Fang Liyao Dong | 2017 | Plant Diversity2017，39，5： | 2 |
| 14 | Blue-White Colony Selection of Virus-Infected Isogenic Recipients Based on a Chrysovirus Isolated from Penicillium italicum显示文摘Mycoviruses have been found to infect more than 12 species of Penicillium,but have not been isolated from Penicillium italicum(P.italicum).In this study,we isolated and characterized a new double-stranded RNA(dsRNA)virus,designated Penicillium italicum chrysovirus 1(PiCVl),from the citrus pathogen P.italicum HSPi-YNl.Viral genome sequencing and molecular characterization indicated that PiCV 1 was highly homologous to the previously described Penicillium chrysogenum virus.We further constructed the mutant HSPi-YNl ApksP defective in the polyketide synthase gene(pksP),which is involved in pigment biosynthesis,and these mutants formed albino(white)colonies.Then we applied hyphal anastomosis method to horizontally transmit PiCV 1 from the white virus-donors(i.e.,HSPi-YNl mutants)to wild-type recipients(i.e.,P.italicum strains HSPi-CQ54,HSPi-HB4,and HSPi-HNl),and the desirable PiCV 1-infected isogenic recipients,a certain part of blue wild-type strains,can be eventually selected and confirmed by viral genomic dsRNA profile analysis.This bluewhite colony screening would be an easier method to select virus-infected P.italicum recipients,according to distinguishable color phenotypes between blue virus-recipients and white virus-donors.In summary,the current work newly isolated and characterized PiCVl,verified its horizontal transmission among dually cultured P.italicum isolates,and based on these,established an effective and simplified approach to screen PiCV 1-infected isogenic recipients. | Tingfu Zhang Na Li Yongze Yuan Qianwen Cao Yanfen Chen Binglan Tan Guoqi Li Deli Liu | 2019 | Virologica Sinica2019，34，6： | 2 |
| 15 | All-in-One Deposition to Synergistically Manipulate Perovskite Growth for High-Performance Solar Cell显示文摘Nonradiative recombination losses originating from crystallographic distortions and issues occurring upon interface formation are detrimental for the photovoltaic performance of perovskite solar cells.Herein,we incorporated a series of carbamide molecules(urea,biuret,or triuret)consisting of both Lewis base(-NH2)and Lewis acid(-C=O)groups into the perovskite precursor to simultaneously eliminate the bulk and interface defects.Depending on the different coordination ability with perovskite component,the incorporated molecules can either modify crystallization dynamics allowing for large crystal growth at low temperature(60℃),associate with antisite or undercoordinated ions for defect passivation,or accumulate at the surface as an energy cascade layer to enhance charge transfer,respectively.Synergistic benefits of the above functions can be obtained by rationally optimizing additive combinations in an all-in-one deposition method.As a result,a champion efficiency of 21.6%with prolonged operational stability was achieved in an inverted MAPbI3 perovskite solar cell by combining biuret and triuret additives.The simplified all-in-one fabrication procedure,adaptable to different types of perovskites in terms of pure MAPbI3,mixed perovskite,and all-inorganic perovskite,provides a cost-efficient and reproducible way to obtain high-performance inverted perovskite solar cells. | Yifan Lv Hui Zhang Jinpei Wang Libao Chen Lifang Bian Zhongfu An Zongyao Qian Guoqi Ren Jie Wu Frank Nuesch Wei Huang | 2020 | Research2020，，1： | 2 |
| 16 | Reproductive biology in an invasive plant Solidago canadensis显示文摘Solidago canadensis,a perennial Compositae plant originating from North America,was introduced into China as a horticultural plant in 1935.Under natural condi-tions,S.canadensis allocates large amounts of energy to sexual reproduction and produces many seeds,which reflects an r-strategy with high seed number and small seed size.In addition,naturalized populations have a great capacity to grow clonally with underground stems.S.canadensis has become an invasive weed in eastern China,and has caused serious damages to agricultural production and ecosystems in several provinces in China.In order to understand the reproductive characteristics of S.canadensis and effectively control its spread,we examined soil conditions,seed charac-teristics,seed germination and the capacity for asexual reproduction in different plant parts.We investigated the population dispersion of S.canadensis in fixed sites for three years,and analyzed the seasonal dynamics of the morphological parameters of the underground parts and the caloric values of different organs of S.canadensis.We also compared differences in the root systems of S.canadensis and composite exotic weeds.The following results were obtained:1)Under natural conditions,the germination season of S.canadensis lasts from March to October,with a peak from April to May.Vegetative growth and asexual reproduction are especially vigorous during summer due to high temperatures and soil drought stress.On the other hand,the rainy season proves suitable for seed germination.Most S.canadensis flower between September and January,and fruit in late October.A mature plant can produce about 20000 seeds.The mean weight of 1000 seeds ranges from 0.045 g to 0.050 g,and the mean seed moisture content ranges from 60%to 80%.The light-winged seeds disperse readily by air,water,vehicles,human activity or through livestock.2)S.canadensis seeds have a wide tolerance for different values of pH,salinity and soil moisture.The mean percent germination of seeds is 30%under suitable conditions.The results of seed germination under various environmental stresses and investigation of soil conditions indicate that well-aerated,slightly acidic soils with low salinity are suitable for the growth of S.canadensis.Additionally,S.canadensis has a high tolerance for contamination by heavy metal elements including Zn,Cu and Pb,but has low accumulation coefficients for these elements.3)S.canadensis reproduces asexually via underground rhizomes and nodes on the stem base to recruit new individuals,and in plants that experience mechanical damage,this repro-ductive strategy is used to produce clonal shoots.The capacity for asexual reproduction among different plant parts rank as follows:underground parts>stem-base(20 cm)>stem-base(30 cm)>stem-base(45 cm)>stem.Further,with increasing mechanical damage,the quantity of shoots produced by the plant decreases.4)The morphological parameters of the root system of S.canadensis including length,surface area,volume,and average diameter are greater than for composite exotic weeds.These parameters indicate that S.canadensis has the physiological potential to widely invade China.5)The aboveground growth rate and most of the underground morphological parameters vary remarkably among the seasons,with a peak normally occurring in September.In August,a fraction of the energy in leaves and stems is allocated underground to increase fine root growth and water uptake during hot weather.Additionally,the seasonal dynamics of the underground morphological parameters and the caloric values of different organs of S.canadensis enhance its reproductive ability.Based on the results above,we conclude that S.canadensis has great invasive potential in China.We suggest that urgent measures should be taken to control its further spread,and to minimize its impact on local plant diversity. | HUANG Hua GUO Shuiliang CHEN Guoqi | 2007 | Frontiers in Biology2007，2，2： | 1 |
| 17 | Petroleum systems of the oldest gas field in China: Neoproterozoic gas pools in the Weiyuan gas field, Sichuan Basin显示文摘 | Guoqi Wei Gengsheng Chen Shangming Du Lin Zhang Wei Yang | 2008 | Marine and Petroleum Geology2008，，4： | 1 |
| 18 | Longmen Shan fold-thrust belt and its relation to the western Sichuan Basin in central China: New insights from hydrocarbon exploration显示文摘 | JIA Dong WEI Guoqi CHEN Zhuxin etal | 2006 | AAPG Bulletin2006，90，9： | 1 |
| 19 | Longmen Shan fold-thrust belt and its relation to western Sichuan Basin in central China:New insights from hydrocarbon exploration显示文摘 | Dong Jia Guoqi Wei Zhuxin Chen | 2006 | AAPG2006，90，： | 1 |
| 20 | Longmen Shan fold thrust belt and its relation to the western Sichuan Basin in central China:New insights from hydrocarbon exploration显示文摘 | Jia Dong Wei Guoqi Chen Zhuxin | 2006 | American Association of Petroleum Geologists Bulletin2006，90，： | 1 |
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