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High-fat diet and oral infection induced type 2 diabetes and obesity development under different genetic backgrounds 被引量:4
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作者 Iqbal M.Lone Nadav Ben Nun +3 位作者 Aya Ghnaim Arne S.Schaefer Yael Houri-Haddad Fuad A.Iraqi 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第2期131-145,共15页
Background:Type 2 diabetes(T2D)is an adult-onset and obese form of diabetes caused by an interplay between genetic,epigenetic,and environmental components.Here,we have assessed a cohort of 11 genetically different col... Background:Type 2 diabetes(T2D)is an adult-onset and obese form of diabetes caused by an interplay between genetic,epigenetic,and environmental components.Here,we have assessed a cohort of 11 genetically different collaborative cross(CC)mouse lines comprised of both sexes for T2D and obesity developments in response to oral infection and high-fat diet(HFD)challenges.Methods:Mice were fed with either the HFD or the standard chow diet(control group)for 12 weeks starting at the age of 8 weeks.At week 5 of the experiment,half of the mice of each diet group were infected with Porphyromonas gingivalis and Fusobacterium nucleatum bacteria strains.Throughout the 12-week experimental period,body weight(BW)was recorded biweekly,and intraperitoneal glucose tolerance tests were performed at weeks 6 and 12 of the experiment to evaluate the glucose tolerance status of mice.Results:Statistical analysis has shown the significance of phenotypic variations between the CC lines,which have different genetic backgrounds and sex effects in different experimental groups.The heritability of the studied phenotypes was estimated and ranged between 0.45 and 0.85.We applied machine learning methods to make an early call for T2D and its prognosis.The results showed that classification with random forest could reach the highest accuracy classification(ACC=0.91)when all the attributes were used.Conclusion:Using sex,diet,infection status,initial BW,and area under the curve(AUC)at week 6,we could classify the final phenotypes/outcomes at the end stage of the experiment(at 12 weeks). 展开更多
关键词 collaborative cross genetic covariance HERITABILITY high-fat diet machine learning mouse model OBESITY type 2 diabetes
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Genetic mutation of Tas2r104/Tas2r105/Tas2r114 cluster leads to a loss of taste perception to denatonium benzoate and cucurbitacin B
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作者 Bowen Niu Lingling Liu +6 位作者 Qian Gao Meng-Min Zhu Lixiang Chen Xiu-Hua Peng Boying Qin Xiaohui Zhou Feng Li 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第3期324-336,共13页
Background:Bitter taste receptors(Tas2rs)are generally considered to sense various bitter compounds to escape the intake of toxic substances.Bitter taste receptors have been found to widely express in extraoral tissue... Background:Bitter taste receptors(Tas2rs)are generally considered to sense various bitter compounds to escape the intake of toxic substances.Bitter taste receptors have been found to widely express in extraoral tissues and have important physiological functions outside the gustatory system in vivo.Methods:To investigate the physiological functions of the bitter taste receptor cluster Tas2r106/Tas2r104/Tas2r105/Tas2r114 in lingual and extraoral tissues,multiple Tas2rs mutant mice and Gnat3 were produced using CRISPR/Cas9 gene-editing technique.A mixture containing Cas9 and sgRNA mRNAs for Tas2rs and Gnat3 gene was microinjected into the cytoplasm of the zygotes.Then,T7EN1 assays and sequencing were used to screen genetic mutation at the target sites in founder mice.Quantitative real-time polymerase chain reaction(qRT-PCR)and immunostaining were used to study the expression level of taste signaling cascade and bitter taste receptor in taste buds.Perception to taste substance was also studied using twobottle preference tests.Results:We successfully produced several Tas2rs and Gnat3 mutant mice using the CRISPR/Cas9 technique.Immunostaining results showed that the expression of GNAT3 and PLCB2 was not altered in Tas2rs mutant mice.But qRT-PCR results revealed the changed expression profile of m Tas2rs gene in taste buds of these mutant mice.With two-bottle preference tests,these mutant mice eliminate responses to cycloheximide due to genetic mutation of Tas2r105.In addition,these mutant mice showed a loss of taste perception to quinine dihydrochloride,denatonium benzoate,and cucurbitacin B(CuB).Gnat3-mediated taste receptor and its signal pathway contribute to CuB perception.Conclusions:These findings implied that these mutant mice would be a valuable means to understand the biological functions of TAS2Rs in extraoral tissues and investigate bitter compound-induced responses mediated by these TAS2Rs in many extraoral tissues. 展开更多
关键词 bitter taste receptor CRISPR/Cas9 genetic mutation two-bottle preference test type 2 taste receptors(Tas2rs)
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Stair climbing,genetic predisposition,and the risk of incident type 2 diabetes:A large population-based prospective cohort study
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作者 Yuanjue Wu Mengyun Luo +1 位作者 Xiao Tan Liangkai Chen 《Journal of Sport and Health Science》 SCIE CSCD 2023年第2期158-166,共9页
Background:Cross-sectional evidence and small-scale trials suggest positive effects of stair climbing on cardiometabolic disease and glucose regulation.However,few studies have examined the long-term association betwe... Background:Cross-sectional evidence and small-scale trials suggest positive effects of stair climbing on cardiometabolic disease and glucose regulation.However,few studies have examined the long-term association between stair climbing and the incidence of type 2 diabetes(T2D).We aimed to prospectively evaluate the association of stair climbing with T2D and assess modifications by genetic predisposition to T2D.Methods:We included 451,699 adults(mean age=56.3±8.1 years,mean±SD;55.2%females)without T2D at baseline in the UK Biobank and followed up to March 31,2021.Stair climbing information was collected through the touchscreen questionnaire.Genetic risk score for T2D consisted of 424 single nucleotide polymorphisms.Results:During a median follow up of 12.1 years,14,896 T2D cases were documented.Compared with participants who reported no stair climbing,those who climbed stairs regularly had a lower risk of incident T2D(10-50 steps/day:hazard ratio(HR)=0.95,95%confidence interval(95%CI):0.89-1.00;60-100 steps/day:HR=0.92,95%CI:0.87-0.98;110-150 steps/day:HR=0.86,95%CI:0.80-0.91;>150 steps/day:HR=0.93,95%CI:0.87-0.99,p for trend=0.0007).We observed a significant interaction between stair climbing and genetic risk score on the subsequent T2D risk(p for interaction=0.0004),where the risk of T2D showed a downward trend in subjects with low genetic risk and those who reported stair climbing activity of 110-150 steps/day appeared to have the lowest overall T2D risk among those with intermediate to high genetic risk.Conclusion:A higher number of stairs climbed at home was associated with lower T2D incidence risk,especially among individuals with a low genetic predisposition to T2D.These findings highlight that stair climbing,as incidental physical activity,offers a simple and low-cost complement to public health interventions for T2D prevention. 展开更多
关键词 COHORT genetic risk score Stair climbing type 2 diabetes UK Biobank
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Clinical and genetic diagnosis of autosomal dominant osteopetrosis typeⅡin a Chinese family:A case report
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作者 Hong-Ping Gong Yan Ren +4 位作者 Pan-Pan Zha Wen-Yan Zhang Jin Zhang Zhi-Wen Zhang Chun Wang 《World Journal of Clinical Cases》 SCIE 2023年第3期700-708,共9页
BACKGROUND Osteopetrosis is a rare genetic disorder characterized by increased bone density due to defective bone resorption of osteoclasts.Approximately,80%of autosomal dominant osteopetrosis type II(ADO-II)patients ... BACKGROUND Osteopetrosis is a rare genetic disorder characterized by increased bone density due to defective bone resorption of osteoclasts.Approximately,80%of autosomal dominant osteopetrosis type II(ADO-II)patients were usually affected by heterozygous dominant mutations in the chloride voltage-gated channel 7(ClCN7)gene and present early-onset osteoarthritis or recurrent fractures.In this study,we report a case of persistent joint pain without bone injury or underlying history.CASE SUMMARY We report a 53-year-old female with joint pain who was accidentally diagnosed with ADO-II.The clinical diagnosis was based on increased bone density and typical radiographic features.Two heterozygous mutations in the ClCN7 and Tcell immune regulator 1(TCIRG1)genes by whole exome sequencing were identified in the patient and her daughter.The missense mutation(c.857G>A)occurred in the CLCN7 gene p.R286Q,which is highly conserved across species.The TCIRG1 gene point mutation(c.714-20G>A)in intron 7(near the splicing site of exon 7)had no effect on subsequent transcription.CONCLUSION This ADO-II case had a pathogenic CLCN7 mutation and late onset without the usual clinical symptoms.For the diagnosis and assessment of the prognosis for osteopetrosis,genetic analysis is advised. 展开更多
关键词 OSTEOPETROSIS Autosomal dominant osteopetrosis type DIAGNOSIS genetic analysis Case report
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Geochemical Characteristics and Genetic Types of Natural Gas in the Xinchang Gas Field, Sichuan Basin, SW China 被引量:11
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作者 WU Xiaoqi LIU Quanyou +5 位作者 LIU Guangxiang WANG Ping LI Huaji MENG Qingqiang CHEN Yingbin ZENG Huasheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2200-2213,共14页
The molecular compositions and stable carbon and hydrogen isotopic compositions of natural gas from the Xinchang gas field in the Sichuan Basin were investigated to determine the genetic types. The natural gas is main... The molecular compositions and stable carbon and hydrogen isotopic compositions of natural gas from the Xinchang gas field in the Sichuan Basin were investigated to determine the genetic types. The natural gas is mainly composed of methane (88.99%-98.01%), and the dryness coefficient varies between 0.908 and 0.997. The gas generally displays positive alkane carbon and hydrogen isotopic series. The geochemical characteristics and gas-source correlation indicate that the gases stored in the 5th member of the Upper Triassic Xujiahe Formation are coal-type gases which are derived from source rocks in the stratum itself. The gases reservoired in the 4th member of the Xujiahe Formation and Jurassic strata in the Xinchang gas field are also coal-type gases that are derived from source rocks in the 3rd and 4th members of the Xujiahe Formation. The gases reservoired in the 2nd member of the Upper Triassic Xujiahe Formation are mainly coal-type gases with small amounts of oil-type gas that is derived from source rocks in the stratum itself. This is accompanied by a small amount of contribution brought by source rocks in the Upper Triassic Ma'antang and Xiaotangzi formations. The gases reservoired in the 4th member of the Middle Triassic Leikoupo Formation are oil-type gases and are believed to be derived from the secondary cracking of oil which is most likely to be generated from the Upper Permian source rocks. 展开更多
关键词 natural gas geochemical characteristics genetic types Xinchang gas field western Sichuan Basin
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Genetic Types of Meter-Scale Cyclic Sequences and Fabric Natures of Facies Succession 被引量:14
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作者 Mei Mingxiang Xu Debin Zhou Hongrui Institute of Earth Sciences and Natural Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 2000年第4期3-10,共8页
Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result f... Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result from the sedimentation governed by different sediment sources and sedimentary dynamic conditions in different paleogeographical backgrounds, corresponding to high-frequency sea-level changes. Naturally, this is the fundamental criterion for the classification of genetic types of meter-scale cyclic sequences. The widespread development in stratigraphic records and the regular vertical stacking patterns in long-term sequences, the evolution characters of earth history and the genetic types reflected by specific fabric natures of facies successions in different paleogeographical settings, all that show meter-scale cyclic sequences are not only the elementary working units in stratigraphy and sedimentology, but also the replenishment and extension of parasequence of sequence stratigraphy. Two genetic kinds of facies succession for meter-scale cyclic sequence in neritic-facies strata of carbonate and clastic rocks, are normal grading succession mainly formed by tidal sedimentation and inverse grading succession chiefly made by wave sedimentation, and both of them constitute generally shallowing upward succession, the thickness of which ranges from several tens of centimeters to several meters. The classification of genetic types of meter-scale cyclic sequence could be made in terms of the fabric natures of facies succession, and carbonate meter-scale cyclic sequences could be divided into four types: L-M type, deep-water asymmetrical type, subtidal type and peritidal type. Clastic meter-scale cyclic sequences could be grouped into two types: tidal-dynamic type and wave-dynamic type. The boundaries of meter-scale cyclic sequences are marked by instantaneous punctuated surface formed by non-deposition resulting from high-frequency level changes, which include instantaneous exposed punctuated surface, drowned punctuated surface as well as their relative surface. The development of instantaneous punctuated surface used as the boundary of meter-scale cyclic sequence brings about the limitations of Walter's Law on the explanation of facies distribution in time and space, and reaffirm the importance of Sander's Rule on analysis of stratigraphic records. These non-continuous surface could be traced for long distance and some could be correlative within same basin range. The study of meter-scale cyclic sequences and their regularly vertical stacking patterns in long-term sequences indicate that the research into cyclicity of stratigraphic records is a useful way to get more regularity from stratigraphic records that are frequently complex as well as non-integrated. 展开更多
关键词 genetic types fabric natures of facies succession meter-scale cyclic sequences.
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Genetic Types and Metallogenic Model for the Polymetallic Copper–Gold Deposits in the Tongling Ore District, Anhui Province, Eastern China 被引量:6
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作者 FU Zhongyang XU Xiaochun +4 位作者 HE Jun FAN Ziliang XIE Qiaoqin DU Jianguo CHEN Fang 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2019年第1期88-110,共23页
The Tongling ore district is one of the most economically important ore areas in the Middle–Lower Yangtze River Metallogenic Belt, eastern China. It contains hundreds of polymetallic copper–gold deposits and occurre... The Tongling ore district is one of the most economically important ore areas in the Middle–Lower Yangtze River Metallogenic Belt, eastern China. It contains hundreds of polymetallic copper–gold deposits and occurrences. Those deposits are mainly clustered(from west to east) within the Tongguanshan, Shizishan, Xinqiao, Fenghuangshan, and Shatanjiao orefields. Until recently, the majority of these deposits were thought to be skarn-or porphyry–skarn-type deposits; however there have been recent discoveries of numerous vein-type Au, Ag, and Pb-Zn deposits that do not fall into either of these categories. This indicates that there is some uncertainty over this classification. Here, we present the results of several systematic geological studies of representative deposits in the Tongling ore district. From investigation of the ore-controlling structures, lithology of the host rock, mineral assemblages, and the characteristics of the mineralization and alteration within these deposits, three genetic types of deposits(skarn-, porphyry-, and vein-type deposits) have been identified. The spatial and temporal relationships between the orebodies and Yanshanian intrusions combined with the sources of the ore-forming fluids and metals, as well as the geodynamic setting of this ore district, indicate that all three deposit types are genetically related each other and constitute a magmatic–hydrothermal system. This study outlines a model that relates the polymetallic copper–gold porphyry-, skarn-, and vein-type deposits within the Tongling ore district. This model provides a theoretical basis to guide exploration for deep-seated and concealed porphyry-type Cu(–Mo, –Au) deposits as well as shallow vein-type Au, Ag, and Pb–Zn deposits in this area and elsewhere. 展开更多
关键词 POLYMETALLIC copper–gold deposits genetic types METALLOGENIC model magmatic–hydrothermal system TONGLING ore district Anhui Province
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Genetic types and distribution of shallow-buried natural gases 被引量:5
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作者 Gao Yang Jin Qiang Zhu Guangyou 《Petroleum Science》 SCIE CAS CSCD 2010年第3期347-354,共8页
Great volumes of shallow-buried (〈2,000 m) natural gases which are mainly composed of biogases and low-mature gases have been found in the Mesozoic-Cenozoic sedimentary basins in China. Many shallow gas reservoirs ... Great volumes of shallow-buried (〈2,000 m) natural gases which are mainly composed of biogases and low-mature gases have been found in the Mesozoic-Cenozoic sedimentary basins in China. Many shallow gas reservoirs in China are characterized by coexistence of biogas and low-mature gas, so identifying the genetic types of shallow gases is important for exploration and development in sedimentary basins. In this paper, we study the gas geochemistry characteristics and distribution in different basins, and classify the shallow gas into two genetic types, biogas and low-mature gas. The biogases are subdivided further into two subtypes by their sources, the source rock-derived biogas and hydrocarbon-derived biogas. Based on the burial history of the source rocks, the source rock-derived biogases are divided into primary and secondary biogas. The former is generated from the source rocks in the primary burial stage, and the latter is from uplifted source rocks or those in a secondary burial stage. In addition, the identifying parameters of each type of shallow gas are given. Based on the analysis above, the distributions of each type of shallow gas are studied. The primary biogases generated from source rocks are mostly distributed in Quaternary basins or modem deltas. Most of them migrate in watersoluble or diffused mode, and their migration distance is short. Reservoir and caprock assemblages play an important role in primary biogas accumulation. The secondary biogases are distributed in a basin with secondary burial history. The oil-degraded biogases are distributed near heavy oil pools. The low-mature gases are widely distributed in shallow-buried reservoirs in the Meso-Cenozoic basins. 展开更多
关键词 Primary biogas secondary biogas oil-degraded biogas low-mature gas genetic type gas identification gas accumulation DISTRIBUTION
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Rock Series and Genetic Types of Granitoids in the Western Kunlun Orogenic Belt,China 被引量:5
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作者 JIANG Yaohui ZHOU Xunruo +3 位作者 RUI Xingjian GUO Kunyi HE Jurui YANG Wanzhi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第1期19-26,共8页
A systematic geological and geochemical study was conducted for the granitoids of different periods in the western Kunlun orogenic belt. The study indicates that the granitoids belong to tholeiitic, calc-alkaline, hig... A systematic geological and geochemical study was conducted for the granitoids of different periods in the western Kunlun orogenic belt. The study indicates that the granitoids belong to tholeiitic, calc-alkaline, high-K calc-alkaline, alkaline and shoshonitic series, and that there are 5 genetic types, i.e., I-, S-, M-, A- and SH-type, of which SH-type is first put forward in this paper, which corresponds to shoshonitic granitoids. 展开更多
关键词 GRANITOID rock series genetic type western Kunlun orogenic belt
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Genetic types and distinguished characteristics of dolomite and the origin of dolomite reservoirs 被引量:1
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作者 ZHAO Wenzhi SHEN Anjiang +3 位作者 QIAO Zhanfeng PAN Liyin HU Anping ZHANG Jie 《Petroleum Exploration and Development》 2018年第6期983-997,共15页
To find out the origin of dolomite, the precipitation of primary dolomite, and the formation of pores in dolomite, petrologic and geochemical characteristics of typical samples from Sichuan and Tarim Basin were analyz... To find out the origin of dolomite, the precipitation of primary dolomite, and the formation of pores in dolomite, petrologic and geochemical characteristics of typical samples from Sichuan and Tarim Basin were analyzed based on the previous understandings, and three aspects of results were achieved.(1) A classification of dolomite origins based on petrologic features, forming environment, and time sequence was proposed, which shows clear boundaries of diagenetic and characteristic realms and evolved clues between different types of dolomite.(2) Petrographic and geochemical identification marks for different types of dolomite were presented, revealing that the orderly geochemical variation of different types of dolomite is the response to the change of forming environment of dolomite during continuous time sequence.(3) The contribution of dolomitization to the formation of porosity was re-evaluated, revealing that the porosity in dolomite was mostly attributed to the primary pores and supergene dissolution and burial dissolution, and early dolomitization was conducive to the preservation of primary pores. These understandings are of great theoretical significance for identifying the origins and types of dolomite, and can guide the prediction of dolomite reservoirs. 展开更多
关键词 DOLOMITE genetic types DOLOMITE distinguished CHARACTERISTICS DOLOMITE POROSITY ORIGIN protodolomite PRIMARY POROSITY
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Geochemical characteristics and genetic types of crude oils from the Tertiary system in the southern part of western Qaidam Basin,Northwest China 被引量:5
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作者 LI Hongbo ZHANG Min +1 位作者 ZHANG Chunming PENG Dehua 《Chinese Journal Of Geochemistry》 EI CAS 2008年第3期285-290,共6页
Crude oil samples taken from the southern part of western Qaidam Basin were analyzed with GC/MS in order to understand the geochemical characteristics of crude oils.The results reveal that most crude oils are characte... Crude oil samples taken from the southern part of western Qaidam Basin were analyzed with GC/MS in order to understand the geochemical characteristics of crude oils.The results reveal that most crude oils are characterized by high abundance of gammacerane and C35 homohopane,which are the representative characteristics of saline lacustrine crude oils.Based on the variation of the ratios of gammacerane/C30 hopane(G/H) and C35 homoho-pane/C34 homohopane(C35/C34H),two crude oil groups,A and B,are identified.Group-A crude oils mainly occurr in the north of the study area,with higher ratios of G/H(>0.8) and C35/C34H(>1.2),whereas group-B crude oils,selected from the south of the study area,show lower ratios of G/H(<0.8) and C35/C34H(<1.0).In addition,group-A crude oils are distinguished into three subgroups in accordance with their different ratios of G/H and C35/C34H and different distribution characteristics of n-alkanes,isoprenoids and steranes.These may be helpful for understanding the distribution characteristics of crude oils in the southern part of western Qaidam Basin and providing clues to the forthcoming exploration of crude oils and gas. 展开更多
关键词 中国北方 盆地 天然石油 遗传类型 盐湖
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BASIN-RANGE TRANSITION AND GENETIC TYPES OF SEQUENCE BOUNDARY OF THE QIANGTANG BASIN IN NORTHERN TIBET
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作者 Yin Fuguang, Xu Xiaosong (Centre for Tethyan Geology,CAGS) 《地学前缘》 EI CAS CSCD 2000年第S1期141-142,共2页
The surface of sequence boundary is a negative record. Its recognition largely depends on the physics of the sediments below and above the boundaries, or on the different sedimentary structures are synthetic marks for... The surface of sequence boundary is a negative record. Its recognition largely depends on the physics of the sediments below and above the boundaries, or on the different sedimentary structures are synthetic marks for the sedimentation and tectonic movements in the sedimentary basin. The Qiangtang Basin that is in 5000m above the sea level is located in Northern Tibet. The Lazhulung—Jinshajiang suture zone now bound it to the north and the Bangong—Nujiang suture zone to the south. Three second\|order tectonic units have been distinguished, i.e. North Qiangtang depression, Central rise and South Qiangtang depression from north to south.The Upper Permian Riejuichaka Formation is built up of mudstone and mud\|limestone, which is represented by sediments in seamarsh. The Lower Triassic Kuanglu Formation, which exhibits the structure unconformable contact with the overlying Upper Permian strata, is characterized by terrigenous clastic rocks in the lower area and is carbonate rocks in the upwarding area and the Middle Triassic Kuangnan Formation. The Upper Triassic Xiachaka Formation consisting of terrigenous clastic rocks, carbonates rocks and mixed sediments, is confined to the uplift zones. The lower Jurassic volcanic rocks are deposited in continental rift. The middle and Upper Jurassic Yangshiping Group are conformable contact and assembled by the gypsum\|bearing terrigenous clastic rock formations and carbonate rock formation. The Middle Cretaceous and the Paleocene strata is built up of the terrigenous clastic rock formations. 展开更多
关键词 basin\|range TRANSITION genetic types sequence boundar y QIANGTANG BASIN NORTHERN TIBET
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Genetic Types and Distribution of CO_2 Gases in the Huanghua Depression
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作者 JinZhenkui BaiWuhou ZhangXiangxiang 《Petroleum Science》 SCIE CAS CSCD 2005年第2期25-30,共6页
CO2 gas is a nonhydrocarbon gas, with a high economic value and a broad prospect for application. In the Huanghua Depression, there exist many genetic types of CO2 gases, i.e. organic CO2, thermal metamorphic CO2 and ... CO2 gas is a nonhydrocarbon gas, with a high economic value and a broad prospect for application. In the Huanghua Depression, there exist many genetic types of CO2 gases, i.e. organic CO2, thermal metamorphic CO2 and crust-mantle mixed CO2. The distribution of different types of CO2 gases is controlled by different factors. Organic CO2 that occurs mainly around the oil-generating center is associated with hydrocarbon gases as a secondary product and commonly far away from large faults. Thermal metamorphic CO2 occurs mainly in areas where carbonate strata are developed and igneous activity is strong, and tends to accumulate near large faults. CO2 of such an origin is higher in concentration than organic CO2, but lower than crust-mantle mixed CO2. Crust-mantle mixed CO2 occurs mainly along large faults. Its distribution is limited, but its purity is the highest. 展开更多
关键词 Huanghua Depression CO2 gas ORIGIN genetic types DISTRIBUTION
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Genetic types and geochemicai characteristics of natural gases in the Jiyang Depression,China
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作者 Wen-Tao Li Yang Gao Chun-Yan Geng 《Petroleum Science》 SCIE CAS CSCD 2015年第1期81-95,共15页
Natural gases were widely distributed in the Jiyang Depression with complicated component composition, and it is difficult to identify their genesis. Based on investigation of gas composition, carbon isotope ratios, l... Natural gases were widely distributed in the Jiyang Depression with complicated component composition, and it is difficult to identify their genesis. Based on investigation of gas composition, carbon isotope ratios, light hydrocarbon properties, as well as geological analysis, natural gases in the Jiyang Depression are classified into two types, one is organic gas and the other is abiogenic gas. Abiogenic gas is mainly magmatogenic or mantlederived CO2. Organic gases are further divided into coaltype gas, oil-type gas, and biogas according to their kero- gen types and formation mechanisms. The oil-type gases are divided into mature oil-type gas (oil-associated gas) and highly mature oil-type gas. The highly mature oil-type gases can be subdivided into oil-cracking gas and kerogen thermal degradation gas. Identification factors for each kind of hydrocarbon gas were summarized. Based on genesis analysis results, the genetic types of gases buried in different depths were discussed. Results showed that shallow gases (〈1,500 m) are mainly mature oil-type gases, biogas, or secondary gases. Secondary gases are rich in methane because of chromatographic separation during migration and secondary biodegradation. Secondary biodegradation leads to richness of heavy carbon isotope ratios in methane and propane. Genesis of middle depth gases (1,500-3,500 m) is dominated by mature oil-type gases.Deep gases (3,500-5,500 m) are mainly kerogen thermal degradation gas, oil-cracking gas, and coal-type gas. 展开更多
关键词 genetic types Natural gases Jiyang Depression Light hydrocarbon properties Carbon isotope ratios Identification factors
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The geochemical characteristics and genetic types of crude oils in the western depression of the Liaohe Basin,China 被引量:1
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作者 MU Guoyan ZHONG Ningning +2 位作者 LIU Bao ZHANG Ning XU Guangjie 《Chinese Journal Of Geochemistry》 EI CAS 2009年第3期328-334,共7页
The physical properties and group compositions of crude oils in the western depression of the Liaohe Basin possess such characteristics as to increase gradually in density, viscosity and wax contents, and decrease in ... The physical properties and group compositions of crude oils in the western depression of the Liaohe Basin possess such characteristics as to increase gradually in density, viscosity and wax contents, and decrease in saturated hydrocarbon and non-hydrocarbon and bitumen contents from the deep level to the shallow level and from the center of the depression to its boundary. Saturated hydrocarbons have various spectra, such as single peak and double peak patterns, front peak and rear peak patterns, and smooth peak and serated peak patterns, as well as the chromatograms of biodegraded n-alkanes. The ratios of Pr/Ph in crude oils from the southern part of the depression are generally higher than those in the northern part. The distribution of regular steranes C27-C29 is predominantly of the ramp type, and only a few samples have relatively high C28 contents in the southern part of the depression. As viewed from their physical properties and geochemical characteristics, crude oils in the study area can be divided into two types (I and II) based on oil-generating sources and sedimentary environments, and then further divided into three sub-types (Ia, Ib and Ic:IIa, IIb and IIIc, respectively) based on their degrees of maturation and secondary transformation. This will provide the reliable basis for oil-source correlation and petroleum exploration and prediction. 展开更多
关键词 地球化学特征 西部凹陷 辽河盆地 成因类型 原油 中国 油源对比 碳氢化合物
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Geology,Genetic Types and Metallogeny of Gold Deposits in the Eastern Tianshan,Xinjiang
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作者 FENG Jianzhong ZENG Yishan FU Shuixing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第3期559-564,共6页
As a typical Palaeozoic island arc system, the eastern Tianshan area, Xinjiang, is different from eastern China but similar to the Meso-Cenozoic island arc metallogenic provinces along the coast of the Pacific Ocean i... As a typical Palaeozoic island arc system, the eastern Tianshan area, Xinjiang, is different from eastern China but similar to the Meso-Cenozoic island arc metallogenic provinces along the coast of the Pacific Ocean in metallogenic environment, geology and geochemistry. Three types of gold deposits, ductile shear zone-hosted gold deposits (Kanggur'), magmatic hydrothermal gold deposits (Jinwozi) and volcanic- or subvolcanic-hosted gold deposits (Xitan and Mazhuangshan), have been identified in this area. Regionally, gold deposits are structurally controlled by the Kanggur Tag ductile shear zone, Shaquanzi fault, Hongliuhe fault and Yamansu fault. Generally, gold mineralization occurs in the transition zones from volcanic rocks to sedimentary rocks. The horizon bearing well-developed jasper is an important indicator for gold mineralization. Each of the three types of gold deposits has its distinctive metallogenic background and geological-geochemical characteristics. 展开更多
关键词 eastern Tianshan GOLD METALLOGENY genetic type GEOLOGY GEOCHEMISTRY
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Carbon isotopic composition and genetic types of natural gas in the Sichuan Basin, China
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作者 Jin-ning peng Dong-yan Wang +2 位作者 Guang-xiang Liu Min Zhang Feng-li Li 《Acta Geochimica》 EI CAS CSCD 2017年第1期102-111,共10页
The origin and genetic types of natural gas in the Sichuan Basin are still disputed.To classify the origin and genetic types in different areas,the paper analyzes the carbon isotopic composition of gases and geologic ... The origin and genetic types of natural gas in the Sichuan Basin are still disputed.To classify the origin and genetic types in different areas,the paper analyzes the carbon isotopic composition of gases and geologic features in the Sichuan Basin.The results showed that the gas sourced from terrestrial layers is typically characterized by terrestrial origin and was mainly accumulated nearby to form reservoir.The carbon isotopic composition of gas showed a normal combination sequence distribution,suggesting that natural gas in continental strata is not affected by secondary alteration or that this deformation is very weak.The gas source is singular,and only gas from the southern and northern Sichuan Basin shows the characteristic of mixed sources.However,marine gas presents the characteristics of an oil-formed gas.The carbon isotopic composition of natural gas in the western and central part of the basin mostly distributes in a normal combination sequence,and few of them showed an inversion,indicating that the gas perhaps had not experienced secondary alteration.The carbon isotopic composition of marine-origin gas in the southern,northern and eastern Sichuan Basin displays a completely different distribution pattern,which is probably caused by different mixing ratio of gas with multi-source and multi-period. 展开更多
关键词 The Sichuan Basin ALKANE Carbon isotope genetic type
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Semen characteristics of the three genetic types of boars reared in Benin
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作者 Ignace O.Dotché Aichatou Gakou +7 位作者 Constant Boris O.B.Bankolé Mahamadou Dahouda Isidore Houaga Nicolas Antoine-Moussiaux Jean Paul Dehoux Pierre Thilmant Benoit G.Koutinhouin Issaka Youssao Abdou Karim 《Asian pacific Journal of Reproduction》 2021年第2期82-89,共8页
Objective:To characterize the semen of three genetic types of boars(local,improved and Large White)reared in Benin.Methods:Semen of local,improved and Large White boars reared in Benin were collected using the gloved ... Objective:To characterize the semen of three genetic types of boars(local,improved and Large White)reared in Benin.Methods:Semen of local,improved and Large White boars reared in Benin were collected using the gloved hand method and analyzed to determine volume,pH,concentration,mobility,motility,and morphology.The effect of the genetic type of boar on semen characteristics was aslo studied.Results:Duration of ejaculation and semen volume of Large White boar were significantly higher than those of local and improved boars(P<0.05).The semen of improved boars had a higher motility score than that of Large White and local boars(P<0.001).The semen of local boars was more concentrated in the spermatozoa than that of improved and Large White boars(P<0.05).The proportion of spermatozoa of improved boars with normal morphology(93.6%)was significantly higher than that of local(82.2%)and Large White boars(81.6%)(P<0.001).The proportion of spermatozoa with folded tails in the semen of Large White boars(9.2%)was significantly higher than that observed in improved(1.8%)and local(5.0%)boars(P<0.001).The proportion of spermatozoa with proximal cytoplasmic droplets in semen of improved boars(2.7%)was significantly lower than that in Large White(6.8%)and local(9.7%)boars(P<0.001).The local(1.5%)and Large White boars(1.1%)showed more spermatozoa with distal cytoplasmic droplets in their semen compared to the improved boars(0.4%).Conclusions:The semen characteristics of pigs reared in Benin vary from one genetic type to another.Each genetic type has a strong point.The Large White boar produces larger semen,the local boar produces more concentrated semen and the improved boar produces spermatozoa that are morphologically better.The semen of these three genetic types can be used in artificial insemination but the improved boar's semen is more recommended. 展开更多
关键词 BOARS SEMEN Local pigs BENIN Semen characteristics genetic types
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The Genetic Types of Baiyun Cave in Lincheng County of Hebei Province
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作者 Yanping SUN Jian WANG +2 位作者 Xiaoman ZHANG Qianhua ZHENG Huafang HUANG 《Asian Agricultural Research》 2013年第10期72-76,共5页
Baiyun Karst Caverns in Lincheng County,Hebei Province,is a rare karst caverns in subhumid climate region of the north.It was developed in carbonatite strata,particularly in Zhangxia formation of the Middle Cambrain s... Baiyun Karst Caverns in Lincheng County,Hebei Province,is a rare karst caverns in subhumid climate region of the north.It was developed in carbonatite strata,particularly in Zhangxia formation of the Middle Cambrain series.Erosion-corrosion landscape and chemical deposition landscape are abundant,They are various shapes,curtain drapery,cave flag,cave shield,stalactite,stalagmite,cave flowers,botryoid,soda straw are developed,especially heligmite,soda straw,cave flowers are the most characteristic. 展开更多
关键词 Baiyun CAVE in Lincheng COUNTY LANDSCAPE genetic t
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Analysis on Genetic Diversity and Isolation Mechanism by Distance of Different Ecological Type Sheep Breeds in Mon-golia Sheep Group 被引量:1
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作者 孙伟 常洪 +4 位作者 冀德君 廖信军 杜垒 鲁生霞 角田健司 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第11期1001-1009,共9页
In the present study with Tan sheep, small-tailed Han sheep, Hu sheep, Tong sheep, and Wadi sheep, we detected the distribution of gene frequency of several microsatellite sites in different chromosomes, the result sh... In the present study with Tan sheep, small-tailed Han sheep, Hu sheep, Tong sheep, and Wadi sheep, we detected the distribution of gene frequency of several microsatellite sites in different chromosomes, the result showed that: 1) Hu sheep was in the status of Hardy-Weinberg extreme disequilibrium (P 〈 0.01), while populations including Tong sheep, small-tailed Han sheep, Tan sheep, and Wadi sheep were in Hardy-Weinberg equilibrium (P 〉 0.05). 2) Variance analysis of the heterozygosity and poly- morphic information content at rnicrosatellite makers showed that there were not significant differences among populations as to heterozygosity and PIC (P 〉 0.05), as to effective number of alleles there were not significant differences both among Tan sheep, Hu sheep, Tong sheep, and Wadi sheep, and between Wadi sheep and small-tailed sheep (P 〉 0.05), but between the former three populations and the latter two populations, there were significant differences (0.01〈 P 〈0.05). The variation levels of small-tailed Han sheep was the highest in the five populations based on microsatellite maker data, subsequently followed by Wadi sheep, Tong sheep, Tan sheep, and then Hu sheep. 3) The phylogenetic relationships of the five sheep populations in this study did not meet the mechanism of isolation by distance, and the genetic differentiation relationships among five sheep populations were not closely linearly correlative with their geography distribution. Our findings supported related records in literature: The five populations originated on different time stage from the primogenitor population and communicated genetically with each other thereafter in the process of natural and artificial selection and on different ecological environment. 展开更多
关键词 Mongolia sheep group different ecological type genetic diversity isolation by distance
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