[Objective] This study aimed to investigate the effects of different land use patterns on soil ecological environment. [Method] Total three representative land use patterns （corn field, cherry tree land, wood land） ...[Objective] This study aimed to investigate the effects of different land use patterns on soil ecological environment. [Method] Total three representative land use patterns （corn field, cherry tree land, wood land） were selected from Hongta District, Yuxi City, and under these three patterns, soil microbial quantity and activity were studied. [Result] Under the three land use patterns, soil microorganisms were domi- nated by bacteria; soil microbial quantity ranked as wood land＇s〉cheery tree land＇s〉 corn field＇s; and total microbial activity, catalase activity and urease activity all ranked as cherry tree land＇s〉wood land＇s〉corn field＇s. [Conclusion] Soil microbial activity and functions are related to farmland management measures, as well as land use pattern and soil nutrients.展开更多
315 species(and cultivars) belonging to 235 genera of 104 families are recorded by investigation in the urban area of Yuxi City,Yunan Province.The investigated areas include urban parks,squares,street green belts,and ...315 species(and cultivars) belonging to 235 genera of 104 families are recorded by investigation in the urban area of Yuxi City,Yunan Province.The investigated areas include urban parks,squares,street green belts,and accessory greenbelts of institutes.It is concluded that the urban plant diversity is inferior to that of natural forest community of the prefecture area.Strategies for urban ecosystem construction in Yuxi City are proposed based on the development goal of ecological garden city.展开更多
The Yuxi （豫西） fold-thrust fracture belt is part of the gigantic fold-thrust fracture belt that extends NW in the southern North China plate. The contents of major elements of tectonites were analyzed by ICP-AES. T...The Yuxi （豫西） fold-thrust fracture belt is part of the gigantic fold-thrust fracture belt that extends NW in the southern North China plate. The contents of major elements of tectonites were analyzed by ICP-AES. The analysis of chemical compositions and new stress minerals indicates： extending from the surrounding country rocks to the center of the fracture belt, the Fe2O3 content gradually increases while the FeO content gradually decreases; regular increase, decrease or peak changes are shown for chemical compositions like SiO2, Al2O3, Fe2O3, MgO, CaO, FeO, loss on ignition, TIO：, K2O, Na2 O, etc.. New stress minerals are developed for the south branch and few for the north branch. The characteristics of chemical compositions and new stress minerals of the thrust fracture demonstrate that the fracture belt has undergone a process from a closed reducing environmental system to a relatively open. oxidizing environmental system, andcompressive fractures have resulted from compression in the late stages of evolution, and the dynamothermal metamorphism and thrusting intensities are different between the south and north branches of the belt, which is strong for the south branch but relatively weak for the north branch.展开更多
[Objective] The aim was to study the reasons of low temperature and characteristics of weather in Yuxi City.[Method] The reasons of low temperature in Yuxi City were expounded.The types of low temperature and their in...[Objective] The aim was to study the reasons of low temperature and characteristics of weather in Yuxi City.[Method] The reasons of low temperature in Yuxi City were expounded.The types of low temperature and their influences on agricultural crops were introduced.The route of cold air and the typical circulation characteristics of low temperature were analyzed.[Result] The low temperature in Yuxi City was formed because of the influence of its topography and climate.The low temperature and cold disaster included frost,low temperature in spring and autumn;the influencing path of cold air in Yuxi City had four paths:northeast,north,northwest and east path.The circulation characteristics of snowing included southerly trough,strong and cold air,and cold front shear;under the long-term control of cold advection of upper air and cold high pressure in the low layer,the radiation,cooling and temperature reducing were the main circulation characteristics of heavy frost;the circulation background of low temperature in August was conductive to the strong cold air intruding the upper air circulation of Yuxi City.The cold trough in the north and low pressure in the south influenced the circulation in Yuxi City.[Conclusion] The study provided reference for the weather report and relevant professionals.展开更多
With the opening of Chinese colleges and the frequent cultural communication among international colleges, Yuxi Normal University, as a local university, has developed very quickly. More and more public signs appear o...With the opening of Chinese colleges and the frequent cultural communication among international colleges, Yuxi Normal University, as a local university, has developed very quickly. More and more public signs appear on campus, both in Chinese and English. But owing to various causes, many non-standard translations can be seen everywhere. From the aspects of commonly applied functions of public signs in colleges, this thesis analyses some common non-standard translations in directing public signs, restricting public signs and calling public signs, and proposes some suggestions on standard translation.展开更多
Yuxi River-Chaohu Lake water suffers greatly from the ecological problems of eutrophication, high turbidity, organic pollution, disappearance of littoral macrophyte, bank erosion and reduction of economic fishery prod...Yuxi River-Chaohu Lake water suffers greatly from the ecological problems of eutrophication, high turbidity, organic pollution, disappearance of littoral macrophyte, bank erosion and reduction of economic fishery products. With Micro-cystis dominant, it is a degenerated and weak ecosystem. Its vicious cycling is caused by too much nutrient load, high spring water level and improper management of the water. The point sources of pollution from cities and industries contribute more than 50% of nutrient load. Soil erosion and fertilizer loss from late rice fields are important factors in non-point nutrient load. The disappearing littoral zone can neither give enough protection for the bank nor provide proper habitats for the biota. The feasibility of ' ecological water level proposal' and means to reduce nutrient load are discussed to improve the habitat environment for both the nature and human being.展开更多
Urban expansion, which has affected ecosystem functioning and services at local to global scale, is projected to have aggravating impacts on landscape in the future. A detailed study on spatiotemporal patterns of Hong...Urban expansion, which has affected ecosystem functioning and services at local to global scale, is projected to have aggravating impacts on landscape in the future. A detailed study on spatiotemporal patterns of Hongta District in Yuxi City over a relatively long timeframe was conducted using multi-temporal Landsat TM, ETM+ and OLI data of 1987-2017 associated with Geographic Information System techniques and landscape analysis approaches. Results showed that sealed surfaces (urban area) have expanded from 1.4% to 11.8%, with an annually increasing rate of 7.63%. Trees, farm areas and barren lands all underwent a slight reduction during this time period, whereby 23.8% of farms and 9.8% of bare lands transferred into sealed surfaces. Focusing on the urban expansion pattern, it presents a uninuclear polarizing polygon mode illustrating the urbanization sprawl over time to all directions. The greatest expansions are seen in NNE and SSE direction, mainly because of the topographic constraints. A trade-off between urbanization and sustainable development is under investigation by reclaiming barren soil at the mountain range to transfer farming areas from low altitude plains to make way for urban growth.展开更多
The Yuxi Cigarets Factory is located in Hongtashan in Yuxi, Yun’nan Province. Established in 1956, the factory is now the country’s biggest modern cigaret enterprise with more than 4,000 employees and fixed assets w...The Yuxi Cigarets Factory is located in Hongtashan in Yuxi, Yun’nan Province. Established in 1956, the factory is now the country’s biggest modern cigaret enterprise with more than 4,000 employees and fixed assets worth RMB600. With more than 100 pieces of world advanced production equipment and high-quality tobacco production bases, the factory produces eight brands including Yuxi, Hongtashan,展开更多
Based on the detailed analyses,multi-proxies such as AMS 14 C dating,grain size,component and morphology of heavy minerals,micromorphology of zircon,magnetic susceptibility,Rb/Sr and Hg content are used to research th...Based on the detailed analyses,multi-proxies such as AMS 14 C dating,grain size,component and morphology of heavy minerals,micromorphology of zircon,magnetic susceptibility,Rb/Sr and Hg content are used to research the paleoflood sediments archived in the Yuxi Site.The research indicates that, since 7.6 kaBP,at least 16 times of paleoflood with water level above Wusong Elevation 147.024 m(a.s.l.) left deposits in the Neolithic layers of unit T0403 from the Yuxi Site.The results are induced from the following aspects:(1)The plaeoflood sediments take on great similarities with modern flood sediments in the Yuxi Site and Zhongba Site in probability cumulative curves which mainly show a pattern of 3 segments in fluvial pattern.(2)There is some resemblance between the heavy mineral components and the zircon shape characteristics of paleoflood deposits and those of modern flood deposits.(3) Magnetic susceptibility values(40.44―70.10SI)are lower than those of sediments from cultural layers (59.59―188.68SI).(4)Hg values(290.71―742.51 ng/g)are lower than those of sediments from cultural layers(344.16―10518.17 ng/g).(5)Rb/Sr values are higher than those of sediments from cultural layers, while those of the 4th,5th,6th,7th,8th cultural layers are high,which shows that they are inundated by paleoflood.The reason for many flood deposits existing is related to the site situated on the first terrace where the Yuxi River joins with the Yangtze River.As there are some similarities between the plaeoflood sediments and those of the Zhongba Site,it is feasible to confirm the existence of paleoflood sediments based on the above points.展开更多
Background Human rickettsioses are worldwide zoonoses and it is not easy to differentiate them from other infectious diseases because of their atypical manifestation. In recent years the number of patients with fever ...Background Human rickettsioses are worldwide zoonoses and it is not easy to differentiate them from other infectious diseases because of their atypical manifestation. In recent years the number of patients with fever of unknown causes from Hongta District CDC, Yuxi city of Yunnan Province has been increasing significantly in the summer. Diagnosis of scrub typhus was made by local clinicians. In order to ascertain the disease, we undertook a laboratory investigation for such patients from August 18 to 26, 2005. Methods Active surveillance was conducted by Hongta District CDC Yuxi city of Yunnan Province from 2002 to 2004 and basic data were obtained from cases confirmed according to clinical definitions. Average incidences and town-level incidences were calculated during the study periods. Blood samples were analyzed by PCR and serological test. Based on the groEL gene sequences a paired general outer primers （Gro-1 and Gro-2） targeting typhus, spotted fever as well as scrub typhus and two paired inner primers （SF1, SR2 and TF1, TR2） for typhus together with spotted fever and scrub typhus, respectively, were designed to perform a multiplex-nested PCR. Serological assay was carried out by indirect immunofluorescence assay with 7 different rickettsial antigens, i.e., R.mossori, R.sibirica, R.conorii, O.tsutsugamushi, B.quintana, B.henselae and Coxilella burnetii phase Ⅱ Ag. Results Epidemiological surveillance showed that from 2002 to 2004, the average incidences of the scrub typhus or scrub typhus with murine typhus were 222.1/10^5, 204.3/10^5 and 109.6/10^5, respectively. Of 13 blood samples taken during acute stage of illness, 6 showed the amplified products for scrub typhus and the sequenced products showed 100%, 99%, 99%, 99%, 99%, 99% similarity to O.tsutsugamushi Karp but they shared the same deduced amino acid sequences, which indicated 100% identity with the heat shock protein of the O.tsutsugamushi Karp strain. Five yielded PCR products for murine typhus and their corresponding nucleotide sequences exhibited 100%, 100%, 99%, 99% and 99% similarity to R. mossori Wilmington and the analyses of predicted amino acid sequences indicated 100%, 100%, 98%, 98% and 98% identity with the heat shock protein of R. mossoriWilmington strain. Of the 8 PCR positive patients, 3 showed a co-infection of scrub typhus with murine typhus. All the 13 serum samples from febrile patients were positive against O. tsutsugamushi and 8 of them were positive against R. mossori. All of the 8 paired specimens had four-fold elevation of antibody against O. tsutsugamushi, and seroconversion for typhus was demonstrated in 3 paired serum samples. Another finding in the study was that a high seropositive prevalence （76.9%） of Q fever was detected. Concluaion It＇s confirmed that co-prevalence of scrub typhus with murine typhus are occurring in Yuxi city of Yunnan province, China. Other rickettsial diseases also need to be investigated in these areas.展开更多
The research of the paleoflood remains from archaeological sites is one of the most important jobs in the environmental archaeology.Based on the traditional archaeological methods and the archaeological finds from the...The research of the paleoflood remains from archaeological sites is one of the most important jobs in the environmental archaeology.Based on the traditional archaeological methods and the archaeological finds from the Yuxi site,Fengdu County of Chongqing,the paper analyzes the difference between the cultural layers and the possible paleoflood layers from various angles,such as contents,shapes of gravels,pottery,etc.,identifies the possible paleoflood deposit layers,i.e.the paleoflood remains of the Yangtze River,and discusses the periodicity of the floods.展开更多
1 Geology Yuxi silver Deposit is located at mountain area of Tuzileike Salt 152 Km south to the Hami in XinjiangAutonomous Region. The ore is of the medium size and may be expected to be larger. Its geotectonicbackgro...1 Geology Yuxi silver Deposit is located at mountain area of Tuzileike Salt 152 Km south to the Hami in XinjiangAutonomous Region. The ore is of the medium size and may be expected to be larger. Its geotectonicbackground belongs to Middle Tianshan crystalline block. The southeast part of regional Yuxi fracturezone, which is made up of a series of secondary faults and slivers-containing fragment tiering, ductileshear zones, and fracture zones, crosses the orefield. The exposed rocks in the orefield are mainly MiddleProterozoic Xingxingxia Group (Chxn), Kawabulak Group (Jxkw) and Upper Permian Darequanzi Formation. Kawabulak Group is a mineralizing wall rock, which is composed of magnesium-rich carbonate andunderwent high greenschist facies metamorphism. It is divided into five laryers by rock. Silver mineraliza-展开更多
全新世时期形成的连续性古洪积层是追溯古环境信息的可靠记录。重庆市丰都县玉溪遗址存在多期连续的文化层与洪积层,但已有研究并未系统分析该遗址区的古洪水发生机制及其气候背景,并且缺乏基于多期古洪积层的周期性研究。(1)本文基于...全新世时期形成的连续性古洪积层是追溯古环境信息的可靠记录。重庆市丰都县玉溪遗址存在多期连续的文化层与洪积层,但已有研究并未系统分析该遗址区的古洪水发生机制及其气候背景,并且缺乏基于多期古洪积层的周期性研究。(1)本文基于动物骨屑AMS ^(14)C年代数据,用Bacon程序拟合玉溪遗址剖面的沉积-年代关系,判定玉溪剖面古洪积层形成时段为约6.4 ka BP~7.3 ka BP。(2)古洪水沉积序列的粒度和端元分析结果显示,玉溪古洪积层由细粉砂-粉砂组成,表明古洪积层为溢岸憩流和滞水缓流堆积而成。(3)孢粉组合、磁化率、Rb/Sr和Si/Al比值等环境指标显示,玉溪剖面的古洪水沉积经历了早期湿热、中期温干、晚期暖湿三个阶段,其中古洪积层在温干阶段的沉积速率最大(30 cm·(100a)^(-1)),而且古洪水发生的频率亦高于湿热期。(4)古洪水沉积序列的小波功率谱分布特征表明,玉溪剖面的古洪水存在约30 a的短周期和约350 a的长周期;其长周期与区域性气候冷事件相关、短周期与ENSO事件导致的夏季风异常有关。本文提出的搬运洪积物的三种动力类型、干湿期古洪水的沉积速率差异以及古洪水泛滥的长短周期,对研究新石器早期重庆地区的人地关系和长江上游的洪水发生机制有参考意义。展开更多
文摘[Objective] This study aimed to investigate the effects of different land use patterns on soil ecological environment. [Method] Total three representative land use patterns （corn field, cherry tree land, wood land） were selected from Hongta District, Yuxi City, and under these three patterns, soil microbial quantity and activity were studied. [Result] Under the three land use patterns, soil microorganisms were domi- nated by bacteria; soil microbial quantity ranked as wood land＇s〉cheery tree land＇s〉 corn field＇s; and total microbial activity, catalase activity and urease activity all ranked as cherry tree land＇s〉wood land＇s〉corn field＇s. [Conclusion] Soil microbial activity and functions are related to farmland management measures, as well as land use pattern and soil nutrients.
文摘315 species(and cultivars) belonging to 235 genera of 104 families are recorded by investigation in the urban area of Yuxi City,Yunan Province.The investigated areas include urban parks,squares,street green belts,and accessory greenbelts of institutes.It is concluded that the urban plant diversity is inferior to that of natural forest community of the prefecture area.Strategies for urban ecosystem construction in Yuxi City are proposed based on the development goal of ecological garden city.
基金This paper is supported by the Key Basic Research Project funded by theChinese Academy of Sciences (No . KZCX2-SW-117) .
文摘The Yuxi （豫西） fold-thrust fracture belt is part of the gigantic fold-thrust fracture belt that extends NW in the southern North China plate. The contents of major elements of tectonites were analyzed by ICP-AES. The analysis of chemical compositions and new stress minerals indicates： extending from the surrounding country rocks to the center of the fracture belt, the Fe2O3 content gradually increases while the FeO content gradually decreases; regular increase, decrease or peak changes are shown for chemical compositions like SiO2, Al2O3, Fe2O3, MgO, CaO, FeO, loss on ignition, TIO：, K2O, Na2 O, etc.. New stress minerals are developed for the south branch and few for the north branch. The characteristics of chemical compositions and new stress minerals of the thrust fracture demonstrate that the fracture belt has undergone a process from a closed reducing environmental system to a relatively open. oxidizing environmental system, andcompressive fractures have resulted from compression in the late stages of evolution, and the dynamothermal metamorphism and thrusting intensities are different between the south and north branches of the belt, which is strong for the south branch but relatively weak for the north branch.
文摘[Objective] The aim was to study the reasons of low temperature and characteristics of weather in Yuxi City.[Method] The reasons of low temperature in Yuxi City were expounded.The types of low temperature and their influences on agricultural crops were introduced.The route of cold air and the typical circulation characteristics of low temperature were analyzed.[Result] The low temperature in Yuxi City was formed because of the influence of its topography and climate.The low temperature and cold disaster included frost,low temperature in spring and autumn;the influencing path of cold air in Yuxi City had four paths:northeast,north,northwest and east path.The circulation characteristics of snowing included southerly trough,strong and cold air,and cold front shear;under the long-term control of cold advection of upper air and cold high pressure in the low layer,the radiation,cooling and temperature reducing were the main circulation characteristics of heavy frost;the circulation background of low temperature in August was conductive to the strong cold air intruding the upper air circulation of Yuxi City.The cold trough in the north and low pressure in the south influenced the circulation in Yuxi City.[Conclusion] The study provided reference for the weather report and relevant professionals.
文摘With the opening of Chinese colleges and the frequent cultural communication among international colleges, Yuxi Normal University, as a local university, has developed very quickly. More and more public signs appear on campus, both in Chinese and English. But owing to various causes, many non-standard translations can be seen everywhere. From the aspects of commonly applied functions of public signs in colleges, this thesis analyses some common non-standard translations in directing public signs, restricting public signs and calling public signs, and proposes some suggestions on standard translation.
文摘Yuxi River-Chaohu Lake water suffers greatly from the ecological problems of eutrophication, high turbidity, organic pollution, disappearance of littoral macrophyte, bank erosion and reduction of economic fishery products. With Micro-cystis dominant, it is a degenerated and weak ecosystem. Its vicious cycling is caused by too much nutrient load, high spring water level and improper management of the water. The point sources of pollution from cities and industries contribute more than 50% of nutrient load. Soil erosion and fertilizer loss from late rice fields are important factors in non-point nutrient load. The disappearing littoral zone can neither give enough protection for the bank nor provide proper habitats for the biota. The feasibility of ' ecological water level proposal' and means to reduce nutrient load are discussed to improve the habitat environment for both the nature and human being.
文摘Urban expansion, which has affected ecosystem functioning and services at local to global scale, is projected to have aggravating impacts on landscape in the future. A detailed study on spatiotemporal patterns of Hongta District in Yuxi City over a relatively long timeframe was conducted using multi-temporal Landsat TM, ETM+ and OLI data of 1987-2017 associated with Geographic Information System techniques and landscape analysis approaches. Results showed that sealed surfaces (urban area) have expanded from 1.4% to 11.8%, with an annually increasing rate of 7.63%. Trees, farm areas and barren lands all underwent a slight reduction during this time period, whereby 23.8% of farms and 9.8% of bare lands transferred into sealed surfaces. Focusing on the urban expansion pattern, it presents a uninuclear polarizing polygon mode illustrating the urbanization sprawl over time to all directions. The greatest expansions are seen in NNE and SSE direction, mainly because of the topographic constraints. A trade-off between urbanization and sustainable development is under investigation by reclaiming barren soil at the mountain range to transfer farming areas from low altitude plains to make way for urban growth.
文摘The Yuxi Cigarets Factory is located in Hongtashan in Yuxi, Yun’nan Province. Established in 1956, the factory is now the country’s biggest modern cigaret enterprise with more than 4,000 employees and fixed assets worth RMB600. With more than 100 pieces of world advanced production equipment and high-quality tobacco production bases, the factory produces eight brands including Yuxi, Hongtashan,
基金Supported by the National Natural Science Foundation of China(Grant No.90411015)the National Science and Technology Support Project(Grant No.2006BAK21B02)+3 种基金the University Doctoral Foundation(Grant No.20050284011)the Foundation of Important Basic Research at Nanjing University(Grant No.0209005206)the Open Foundation of the State Key Laboratory of Loess and Qua-ternary Geology from the Institute of Earth Environment,CAS(Grant No.SKLLQG0503)the Physical Geography of"985"Items and the Test Foundation of Modern Analyses Center of Nanjing University(Grant No.0209001309)
文摘Based on the detailed analyses,multi-proxies such as AMS 14 C dating,grain size,component and morphology of heavy minerals,micromorphology of zircon,magnetic susceptibility,Rb/Sr and Hg content are used to research the paleoflood sediments archived in the Yuxi Site.The research indicates that, since 7.6 kaBP,at least 16 times of paleoflood with water level above Wusong Elevation 147.024 m(a.s.l.) left deposits in the Neolithic layers of unit T0403 from the Yuxi Site.The results are induced from the following aspects:(1)The plaeoflood sediments take on great similarities with modern flood sediments in the Yuxi Site and Zhongba Site in probability cumulative curves which mainly show a pattern of 3 segments in fluvial pattern.(2)There is some resemblance between the heavy mineral components and the zircon shape characteristics of paleoflood deposits and those of modern flood deposits.(3) Magnetic susceptibility values(40.44―70.10SI)are lower than those of sediments from cultural layers (59.59―188.68SI).(4)Hg values(290.71―742.51 ng/g)are lower than those of sediments from cultural layers(344.16―10518.17 ng/g).(5)Rb/Sr values are higher than those of sediments from cultural layers, while those of the 4th,5th,6th,7th,8th cultural layers are high,which shows that they are inundated by paleoflood.The reason for many flood deposits existing is related to the site situated on the first terrace where the Yuxi River joins with the Yangtze River.As there are some similarities between the plaeoflood sediments and those of the Zhongba Site,it is feasible to confirm the existence of paleoflood sediments based on the above points.
基金the grant from the National Key Technologies R&D Program(No.2003BA712A02)
文摘Background Human rickettsioses are worldwide zoonoses and it is not easy to differentiate them from other infectious diseases because of their atypical manifestation. In recent years the number of patients with fever of unknown causes from Hongta District CDC, Yuxi city of Yunnan Province has been increasing significantly in the summer. Diagnosis of scrub typhus was made by local clinicians. In order to ascertain the disease, we undertook a laboratory investigation for such patients from August 18 to 26, 2005. Methods Active surveillance was conducted by Hongta District CDC Yuxi city of Yunnan Province from 2002 to 2004 and basic data were obtained from cases confirmed according to clinical definitions. Average incidences and town-level incidences were calculated during the study periods. Blood samples were analyzed by PCR and serological test. Based on the groEL gene sequences a paired general outer primers （Gro-1 and Gro-2） targeting typhus, spotted fever as well as scrub typhus and two paired inner primers （SF1, SR2 and TF1, TR2） for typhus together with spotted fever and scrub typhus, respectively, were designed to perform a multiplex-nested PCR. Serological assay was carried out by indirect immunofluorescence assay with 7 different rickettsial antigens, i.e., R.mossori, R.sibirica, R.conorii, O.tsutsugamushi, B.quintana, B.henselae and Coxilella burnetii phase Ⅱ Ag. Results Epidemiological surveillance showed that from 2002 to 2004, the average incidences of the scrub typhus or scrub typhus with murine typhus were 222.1/10^5, 204.3/10^5 and 109.6/10^5, respectively. Of 13 blood samples taken during acute stage of illness, 6 showed the amplified products for scrub typhus and the sequenced products showed 100%, 99%, 99%, 99%, 99%, 99% similarity to O.tsutsugamushi Karp but they shared the same deduced amino acid sequences, which indicated 100% identity with the heat shock protein of the O.tsutsugamushi Karp strain. Five yielded PCR products for murine typhus and their corresponding nucleotide sequences exhibited 100%, 100%, 99%, 99% and 99% similarity to R. mossori Wilmington and the analyses of predicted amino acid sequences indicated 100%, 100%, 98%, 98% and 98% identity with the heat shock protein of R. mossoriWilmington strain. Of the 8 PCR positive patients, 3 showed a co-infection of scrub typhus with murine typhus. All the 13 serum samples from febrile patients were positive against O. tsutsugamushi and 8 of them were positive against R. mossori. All of the 8 paired specimens had four-fold elevation of antibody against O. tsutsugamushi, and seroconversion for typhus was demonstrated in 3 paired serum samples. Another finding in the study was that a high seropositive prevalence （76.9%） of Q fever was detected. Concluaion It＇s confirmed that co-prevalence of scrub typhus with murine typhus are occurring in Yuxi city of Yunnan province, China. Other rickettsial diseases also need to be investigated in these areas.
基金Supported by the Key Project of the National Natural Science Foundation of China(Grant No.90411015)the University Doctoral Foundation(Grant No.20050284011)+2 种基金the Foundation of Important Basis Research at Nanjing University(Grant No.0209005206)the Open Foundation of the State Key Laboratory of Loessand Quaternary Geology from the Institute of Earth Environment,CAS(Grant No.SKLLQG0503)the Physical Geography of‘985’Items and the Test Foundation ofModern Analyses Center of Nanjing University(Grant No 0209001309)
文摘The research of the paleoflood remains from archaeological sites is one of the most important jobs in the environmental archaeology.Based on the traditional archaeological methods and the archaeological finds from the Yuxi site,Fengdu County of Chongqing,the paper analyzes the difference between the cultural layers and the possible paleoflood layers from various angles,such as contents,shapes of gravels,pottery,etc.,identifies the possible paleoflood deposit layers,i.e.the paleoflood remains of the Yangtze River,and discusses the periodicity of the floods.
文摘1 Geology Yuxi silver Deposit is located at mountain area of Tuzileike Salt 152 Km south to the Hami in XinjiangAutonomous Region. The ore is of the medium size and may be expected to be larger. Its geotectonicbackground belongs to Middle Tianshan crystalline block. The southeast part of regional Yuxi fracturezone, which is made up of a series of secondary faults and slivers-containing fragment tiering, ductileshear zones, and fracture zones, crosses the orefield. The exposed rocks in the orefield are mainly MiddleProterozoic Xingxingxia Group (Chxn), Kawabulak Group (Jxkw) and Upper Permian Darequanzi Formation. Kawabulak Group is a mineralizing wall rock, which is composed of magnesium-rich carbonate andunderwent high greenschist facies metamorphism. It is divided into five laryers by rock. Silver mineraliza-
文摘全新世时期形成的连续性古洪积层是追溯古环境信息的可靠记录。重庆市丰都县玉溪遗址存在多期连续的文化层与洪积层,但已有研究并未系统分析该遗址区的古洪水发生机制及其气候背景,并且缺乏基于多期古洪积层的周期性研究。(1)本文基于动物骨屑AMS ^(14)C年代数据,用Bacon程序拟合玉溪遗址剖面的沉积-年代关系,判定玉溪剖面古洪积层形成时段为约6.4 ka BP~7.3 ka BP。(2)古洪水沉积序列的粒度和端元分析结果显示,玉溪古洪积层由细粉砂-粉砂组成,表明古洪积层为溢岸憩流和滞水缓流堆积而成。(3)孢粉组合、磁化率、Rb/Sr和Si/Al比值等环境指标显示,玉溪剖面的古洪水沉积经历了早期湿热、中期温干、晚期暖湿三个阶段,其中古洪积层在温干阶段的沉积速率最大(30 cm·(100a)^(-1)),而且古洪水发生的频率亦高于湿热期。(4)古洪水沉积序列的小波功率谱分布特征表明,玉溪剖面的古洪水存在约30 a的短周期和约350 a的长周期;其长周期与区域性气候冷事件相关、短周期与ENSO事件导致的夏季风异常有关。本文提出的搬运洪积物的三种动力类型、干湿期古洪水的沉积速率差异以及古洪水泛滥的长短周期,对研究新石器早期重庆地区的人地关系和长江上游的洪水发生机制有参考意义。
