Chinese radioglaciological studies on the Antarctic ice sheet(AIS) began in 2004/05 when the 21 st Chinese National Antarctic Research Expedition(CHINARE 21) team arrived at Dome A for the first time and radio echo so...Chinese radioglaciological studies on the Antarctic ice sheet(AIS) began in 2004/05 when the 21 st Chinese National Antarctic Research Expedition(CHINARE 21) team arrived at Dome A for the first time and radio echo sounding(RES) was conducted along the inland traverse and in the Dome A region. Subsequently, more field surveys were conducted along the traverse and in the Dome A region using different radar systems targeting different scientific purposes, such as revealing the landscape of the Gamburtsev Subglacial Mountains by detailed grid RES, or locating a deep ice core drilling site by mapping and studying internal structures, bedrock topography and subglacial conditions in the Dome A region. Furthermore, the evolution of the AIS was inferred from the typical mountain glaciation topography beneath Dome A, and the age of the deep ice core at Kunlun Station was estimated through numerical modeling. Recently, the Snow Eagle 601 airplane was acquired and an airborne geophysical system was constructed to survey the AIS in Princess Elizabeth Land during CHINARE 32(2015/16) and CHINARE 33(2016/17) in order to fill the large data gap there. In this paper, we review both the recent progress of Chinese radioglaciological science in Antarctica and future proposed work.展开更多
Objectives Important clues have been found for potassium prospecting in the Huangjinkou anticline of the northeast Sichuan Basin in the 1970s(Zheng et al.,2015;Lin et al.,2004).In 2008,China Geological Survey launched...Objectives Important clues have been found for potassium prospecting in the Huangjinkou anticline of the northeast Sichuan Basin in the 1970s(Zheng et al.,2015;Lin et al.,2004).In 2008,China Geological Survey launched a prospective investigation of potash resources in the western region of China,and the local governments and private-owned enterprises also responded positively.Then,展开更多
目的探讨固有免疫调节受体TLR4在抵抗生殖道感染过程中对卵泡发育的影响。方法雌性BALB/c小鼠随机分为LPS组、PBS组和未处理组,每组12只。组织学方法计数各组卵泡发育的变化,real time qPCR技术检测TLR成员在LPS组卵巢中的表达模式。体...目的探讨固有免疫调节受体TLR4在抵抗生殖道感染过程中对卵泡发育的影响。方法雌性BALB/c小鼠随机分为LPS组、PBS组和未处理组,每组12只。组织学方法计数各组卵泡发育的变化,real time qPCR技术检测TLR成员在LPS组卵巢中的表达模式。体外培养BALB/c小鼠的卵巢,随机分为LPS刺激组和对照组。利用real time qPCR技术检测卵巢中相关信号分子IL-1β、IL-6、IL-8的表达,利用ELISA检测培养液中E2水平。结果与未处理组相比,LPS组卵巢的原始卵泡数目降低,闭锁卵泡数目升高,差异有统计学意义(P<0.05)。LPS组中,与其他TLR成员相比TLR4在小鼠卵巢中呈现较高水平的表达,差异有统计学意义(P<0.05)。离体实验显示,与对照组相比,LPS刺激组TLR4的下游炎症因子IL-1β、IL-8和IL-6的表达升高,但E2水平降低,差异有统计学意义(P<0.05)。结论LPS使TLR4诱导炎症反应,同时还影响了卵泡发育。这对于发现感染导致的卵泡发育不良的新调控机制具有重要意义。展开更多
国际冰川学会(International Glaciological Society,IGS)于2019年7月8—12日在美国加利福尼亚州旧金山斯坦福大学举行了“雷达冰川学50周年国际学术研讨会”(International Symposium on Five Decades of Radioglaciology)。此次会议...国际冰川学会(International Glaciological Society,IGS)于2019年7月8—12日在美国加利福尼亚州旧金山斯坦福大学举行了“雷达冰川学50周年国际学术研讨会”(International Symposium on Five Decades of Radioglaciology)。此次会议系统回顾了雷达冰川学的发展历程以及取得的科学研究成果。冰雷达探测是一种在局部、区域和全球尺度上探测冰冻圈下表面和其他星球冰下条件的强大地球物理技术。因此,一系列用于雷达探测的轨道、机载、拖曳和原位探测的仪器、平台以及数据分析方法被用于观测、研究冰层厚度、基底地形和冰下环境。目前,雷达冰川学已经走过50年的历史。特别是近年来,雷达探测数据被应用于估计水冰的范围和形态、冰盖表面、冰床的几何形态、基底融化的空间变化、冰面温度以及冻融基底之间的过渡带。行星冰雷达探测仪也被用于或计划用于观测火星、月球以及木星的彗星及其冰卫星的地下和近地表状况。展开更多
2019年6月9—14日,国际摄影测量与遥感学会(The International Society for Photogrammetryand Remote Sensing,ISPRS)在荷兰恩斯赫德(Enschede)特文特大学(University of Twente)举行了2019地球空间周(ISPRS Geospatial Week 2019)活...2019年6月9—14日,国际摄影测量与遥感学会(The International Society for Photogrammetryand Remote Sensing,ISPRS)在荷兰恩斯赫德(Enschede)特文特大学(University of Twente)举行了2019地球空间周(ISPRS Geospatial Week 2019)活动。本次地球空间信息周设有云包映射和地理空间大数据、联合欧洲校准和定位研讨会、行星遥感和测绘、空间数据质量国际研讨会、全球变化研究中的冰冻圈和水圈研讨会(Cryosphere and Hydrosphere for Global Change Studies,CHGCS 2019)、三维地图和导航多传感器系统研讨、高光谱传感符合机器学习和模式分析等专题。展开更多
第33届冰架过程研究论坛(33rd Forum for Research into Ice Shelf Processes,FRISP)于2019年9月14—18日在英国牛津大学女王学院(The Queen’s College,Oxford)举行;18—19日,国际斯维茨冰川合作组织(International Thwaites Glacier C...第33届冰架过程研究论坛(33rd Forum for Research into Ice Shelf Processes,FRISP)于2019年9月14—18日在英国牛津大学女王学院(The Queen’s College,Oxford)举行;18—19日,国际斯维茨冰川合作组织(International Thwaites Glacier Collaboration,ITGC)举行了学术讨论会。展开更多
During the 21st century,the contribution of the Antarctic*Ice Sheet(AIS)to sea level rise has been increasing,affecting coastal regions and their large populations and economies(Moore et al.,2018).The ice loss from th...During the 21st century,the contribution of the Antarctic*Ice Sheet(AIS)to sea level rise has been increasing,affecting coastal regions and their large populations and economies(Moore et al.,2018).The ice loss from the AIS is driven primarily by increased melting of ice shelves by warm ocean waters and the subsequent acceleration,retreat and rapid thinning of the major outlet glaciers of the West Antarctic ice sheet(IPCC,2019).However,subglacial conditions(thermodynamics and hydrology)of AIS remain poorly understood,despite recent advances in satellite and ground-based observations,and this makes it difficult to project the amount of future ice loss.To better understand the most compelling scientific issues addressing subglacial conditions,and following several recent technical and operational advances,the National Natural Science Foundation of China(NSFC)launched a special program named the“Polar Basic Science Frontier”.展开更多
Traveltime tomography is a technique to reconstruct acoustic, seismic, or electromagnetic wave-speed distributions from first arrival traveltime data. The ray paths that should be used for tomographic techniques stro...Traveltime tomography is a technique to reconstruct acoustic, seismic, or electromagnetic wave-speed distributions from first arrival traveltime data. The ray paths that should be used for tomographic techniques strongly depend on the wave-speed distribution. In this paper, a new method is proposed for finding out the ray paths from Fermat's principle, that means the traveltime of the ray path should be a minimum value. The problem of finding out the ray path is actually an optimum problem. Our new method uses the idea to find out the shortest path in a weighted directed graph to solve the problem. The ray paths found out by this method are used in the iterative reconstruction algorithm. Computer simulation result produced by this reconstruction algorithm is better than that by the conventional ones. It also shows that the new algorithm is effective with good convergency and stability.展开更多
目的研究酒石酸美托洛尔联合硫酸镁治疗妊娠期高血压疾病的效果及对尿液蛋白质的影响。方法选择2015年1月—2017年1月在文山州妇幼保健院诊治的妊娠期高血压患者70例,随机分为各35例的两组。对照组静脉滴注硫酸镁,每次60 m L,每10小时1...目的研究酒石酸美托洛尔联合硫酸镁治疗妊娠期高血压疾病的效果及对尿液蛋白质的影响。方法选择2015年1月—2017年1月在文山州妇幼保健院诊治的妊娠期高血压患者70例,随机分为各35例的两组。对照组静脉滴注硫酸镁,每次60 m L,每10小时1次;研究组在对照组基础上口服酒石酸美托洛尔片治疗,初始剂量设定为每次20 mg,每天1次,然后每隔1天将剂量增加12.5 mg,最高剂量为每天150 mg。两组均治疗1个月。比较两组的临床有效率、新生儿结局情况(胎儿早产、胎儿窘迫、新生儿窒息和围产儿死亡),以及HPLLP综合征、产后出血、胎盘早剥等并发症的发生率以及剖宫产率,并检测两组治疗前后的尿钙黏蛋白、24 h尿蛋白以及尿激肽原1水平。结果研究组的有效率为94.29%,明显高于对照组的80.00%,差异有统计学意义(P<0.05)。研究组的不良新生儿结局(胎儿早产、胎儿窘迫、新生儿窒息和围产儿死亡)发生率均低于对照组,差异有统计学意义(P<0.05);研究组的并发症发生率(HPLLP综合征、产后出血、胎盘早剥)及剖宫产率均低于对照组,差异有统计学意义(P<0.05)。两组治疗后的尿钙黏蛋白、24 h尿蛋白以及尿激肽原1水平均明显降低,同组治疗前后比较差异有统计学意义(P<0.05);且研究组明显低于对照组,差异有统计学意义(P<0.05)。结论将酒石酸美托洛尔与硫酸镁联合用于妊娠期高血压疾病的治疗过程中,该方法临床效果显著,可有效改善母婴结局,显著降低尿液蛋白表达水平。展开更多
Dome A, located in the central East Antarctic ice sheet (EAIS), is the highest summit of the Antarctic ice sheet. From ice-sheet evolution modeling results, Dome A is likely to preserve over one million years of the E...Dome A, located in the central East Antarctic ice sheet (EAIS), is the highest summit of the Antarctic ice sheet. From ice-sheet evolution modeling results, Dome A is likely to preserve over one million years of the Earth's paleo-climatic and -environmental records, and considered an ideal deep ice core drilling site. Ice thickness and subglacial topography are critical factors for ice-sheet models to determine the timescale and location of a deep ice core. During the 21st and 24th Chinese National Antarctic Research Expedition (CHINARE 21, 2004/05; CHINARE 24, 2007/08), ground-based ice radar systems were used to a three-dimensional investigation in the central 30 km×30 km region at Dome A. The successfully obtained high resolution and accuracy data of ice thickness and subglacial topography were then interpolated into the ice thickness distribution and subglacial topography digital elevation model (DEM) with a regular grid resolution of 140.5 m×140.5 m. The results of the ice radar investigation indicate that the average ice thickness in the Dome A central 30 km×30 km region is 2233 m, with a minimal ice thickness of 1618 m and a maximal ice thickness of 3139 m at Kunlun Station. The subglacial topography is relatively sharp, with an elevation range of 949-2445 m. The typical, clear mountain glaciation morphology is likely to reflect the early evolution of the Antarctic ice sheet. Based on the ice thickness distribution and subglacial topography characteristics, the location of Kunlun Station was suggested to carry out the first high-resolution, long time-scale deep ice core drilling. However, the internal structure and basal environments at Kunlun Station still need further research to determine.展开更多
基金financially supported by the National Natural Science Foundation of China (Grant nos. 41776186, 41730102 and 41571407)the Chinese Polar Environmental Comprehensive Investigation and Assessment Programs (Grant no. CHINARE-02-02)
文摘Chinese radioglaciological studies on the Antarctic ice sheet(AIS) began in 2004/05 when the 21 st Chinese National Antarctic Research Expedition(CHINARE 21) team arrived at Dome A for the first time and radio echo sounding(RES) was conducted along the inland traverse and in the Dome A region. Subsequently, more field surveys were conducted along the traverse and in the Dome A region using different radar systems targeting different scientific purposes, such as revealing the landscape of the Gamburtsev Subglacial Mountains by detailed grid RES, or locating a deep ice core drilling site by mapping and studying internal structures, bedrock topography and subglacial conditions in the Dome A region. Furthermore, the evolution of the AIS was inferred from the typical mountain glaciation topography beneath Dome A, and the age of the deep ice core at Kunlun Station was estimated through numerical modeling. Recently, the Snow Eagle 601 airplane was acquired and an airborne geophysical system was constructed to survey the AIS in Princess Elizabeth Land during CHINARE 32(2015/16) and CHINARE 33(2016/17) in order to fill the large data gap there. In this paper, we review both the recent progress of Chinese radioglaciological science in Antarctica and future proposed work.
基金funded by the China Geological Survey Bureau of the Western Region in potassium mineral prospect survey evaluation (No.DD20160054)the Sichuan Provincial Geological Prospecting Fund Project (Huangjinkou potash general survey, Xuanhan County, Sichuan Province)the China Postdoctoral Science Fund (No. 2017M620885)
文摘Objectives Important clues have been found for potassium prospecting in the Huangjinkou anticline of the northeast Sichuan Basin in the 1970s(Zheng et al.,2015;Lin et al.,2004).In 2008,China Geological Survey launched a prospective investigation of potash resources in the western region of China,and the local governments and private-owned enterprises also responded positively.Then,
文摘目的探讨固有免疫调节受体TLR4在抵抗生殖道感染过程中对卵泡发育的影响。方法雌性BALB/c小鼠随机分为LPS组、PBS组和未处理组,每组12只。组织学方法计数各组卵泡发育的变化,real time qPCR技术检测TLR成员在LPS组卵巢中的表达模式。体外培养BALB/c小鼠的卵巢,随机分为LPS刺激组和对照组。利用real time qPCR技术检测卵巢中相关信号分子IL-1β、IL-6、IL-8的表达,利用ELISA检测培养液中E2水平。结果与未处理组相比,LPS组卵巢的原始卵泡数目降低,闭锁卵泡数目升高,差异有统计学意义(P<0.05)。LPS组中,与其他TLR成员相比TLR4在小鼠卵巢中呈现较高水平的表达,差异有统计学意义(P<0.05)。离体实验显示,与对照组相比,LPS刺激组TLR4的下游炎症因子IL-1β、IL-8和IL-6的表达升高,但E2水平降低,差异有统计学意义(P<0.05)。结论LPS使TLR4诱导炎症反应,同时还影响了卵泡发育。这对于发现感染导致的卵泡发育不良的新调控机制具有重要意义。
文摘国际冰川学会(International Glaciological Society,IGS)于2019年7月8—12日在美国加利福尼亚州旧金山斯坦福大学举行了“雷达冰川学50周年国际学术研讨会”(International Symposium on Five Decades of Radioglaciology)。此次会议系统回顾了雷达冰川学的发展历程以及取得的科学研究成果。冰雷达探测是一种在局部、区域和全球尺度上探测冰冻圈下表面和其他星球冰下条件的强大地球物理技术。因此,一系列用于雷达探测的轨道、机载、拖曳和原位探测的仪器、平台以及数据分析方法被用于观测、研究冰层厚度、基底地形和冰下环境。目前,雷达冰川学已经走过50年的历史。特别是近年来,雷达探测数据被应用于估计水冰的范围和形态、冰盖表面、冰床的几何形态、基底融化的空间变化、冰面温度以及冻融基底之间的过渡带。行星冰雷达探测仪也被用于或计划用于观测火星、月球以及木星的彗星及其冰卫星的地下和近地表状况。
文摘2019年6月9—14日,国际摄影测量与遥感学会(The International Society for Photogrammetryand Remote Sensing,ISPRS)在荷兰恩斯赫德(Enschede)特文特大学(University of Twente)举行了2019地球空间周(ISPRS Geospatial Week 2019)活动。本次地球空间信息周设有云包映射和地理空间大数据、联合欧洲校准和定位研讨会、行星遥感和测绘、空间数据质量国际研讨会、全球变化研究中的冰冻圈和水圈研讨会(Cryosphere and Hydrosphere for Global Change Studies,CHGCS 2019)、三维地图和导航多传感器系统研讨、高光谱传感符合机器学习和模式分析等专题。
文摘第33届冰架过程研究论坛(33rd Forum for Research into Ice Shelf Processes,FRISP)于2019年9月14—18日在英国牛津大学女王学院(The Queen’s College,Oxford)举行;18—19日,国际斯维茨冰川合作组织(International Thwaites Glacier Collaboration,ITGC)举行了学术讨论会。
基金the National Natural Science Foundation of China(Grant nos.41941006 and 41876230)National key R&D Program of China(Grant no.2019YFC1509102)。
文摘During the 21st century,the contribution of the Antarctic*Ice Sheet(AIS)to sea level rise has been increasing,affecting coastal regions and their large populations and economies(Moore et al.,2018).The ice loss from the AIS is driven primarily by increased melting of ice shelves by warm ocean waters and the subsequent acceleration,retreat and rapid thinning of the major outlet glaciers of the West Antarctic ice sheet(IPCC,2019).However,subglacial conditions(thermodynamics and hydrology)of AIS remain poorly understood,despite recent advances in satellite and ground-based observations,and this makes it difficult to project the amount of future ice loss.To better understand the most compelling scientific issues addressing subglacial conditions,and following several recent technical and operational advances,the National Natural Science Foundation of China(NSFC)launched a special program named the“Polar Basic Science Frontier”.
文摘Traveltime tomography is a technique to reconstruct acoustic, seismic, or electromagnetic wave-speed distributions from first arrival traveltime data. The ray paths that should be used for tomographic techniques strongly depend on the wave-speed distribution. In this paper, a new method is proposed for finding out the ray paths from Fermat's principle, that means the traveltime of the ray path should be a minimum value. The problem of finding out the ray path is actually an optimum problem. Our new method uses the idea to find out the shortest path in a weighted directed graph to solve the problem. The ray paths found out by this method are used in the iterative reconstruction algorithm. Computer simulation result produced by this reconstruction algorithm is better than that by the conventional ones. It also shows that the new algorithm is effective with good convergency and stability.
基金supported by the Ministry of Science and Technology of China (Grant No. 2006BAB18B01)National Natural Science Foundation of China (Grant No. 40476005)Polar Strategy Research Foundation in China (Grant No. 20070215)
文摘Dome A, located in the central East Antarctic ice sheet (EAIS), is the highest summit of the Antarctic ice sheet. From ice-sheet evolution modeling results, Dome A is likely to preserve over one million years of the Earth's paleo-climatic and -environmental records, and considered an ideal deep ice core drilling site. Ice thickness and subglacial topography are critical factors for ice-sheet models to determine the timescale and location of a deep ice core. During the 21st and 24th Chinese National Antarctic Research Expedition (CHINARE 21, 2004/05; CHINARE 24, 2007/08), ground-based ice radar systems were used to a three-dimensional investigation in the central 30 km×30 km region at Dome A. The successfully obtained high resolution and accuracy data of ice thickness and subglacial topography were then interpolated into the ice thickness distribution and subglacial topography digital elevation model (DEM) with a regular grid resolution of 140.5 m×140.5 m. The results of the ice radar investigation indicate that the average ice thickness in the Dome A central 30 km×30 km region is 2233 m, with a minimal ice thickness of 1618 m and a maximal ice thickness of 3139 m at Kunlun Station. The subglacial topography is relatively sharp, with an elevation range of 949-2445 m. The typical, clear mountain glaciation morphology is likely to reflect the early evolution of the Antarctic ice sheet. Based on the ice thickness distribution and subglacial topography characteristics, the location of Kunlun Station was suggested to carry out the first high-resolution, long time-scale deep ice core drilling. However, the internal structure and basal environments at Kunlun Station still need further research to determine.
