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Stratigraphic framework and sedimentary evolution during the Cryogenian-Ediacaran transition in northeastern Sichuan Basin,South China

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Petroleum Science 2024年第2期21卷 823-835页

作者： Yi Zhang Hong-Wei Kuang Yong-Qing Liu Qiang Shi Dong-Ge Wang Ke-Ning Qi Yu-Chong Wang Da-Wei Qiao Xiao-Shuai Chen Li-Zhi Wu Meng tian Long Chen Yi Wei Liao-Yuan Song Jian Li zi-Gang Wu Yun-Qian Liu Xuan-Chun Liu An-Qing Chen Zhi-Wei Liao Institute of Geology Chinese Academy of Geological SciencesBeijing100037China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing400044China No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing401121China Chongqing Institute of Geological Survey Chongqing401122China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu610059SichuanChina

The northeastern Sichuan area in the northern Yangtze margin has unique Ediacaran geological records,especially the Doushantuo Formation(DST),and become a hot research area in recent ***,the Cryogenian-Ediacaran(C-E)boundary has not been precisely identified,which restricts the in-depth study of geological information during this crucial transitional period and is unfavorable for a systematic and complete understanding of the Yangtze Block and even the global paleogeographic *** study conducted stratigraphy,sedimentology,and chronostratigraphy to establish the stratigraphic framework and sedimentary evolution of the C-E transition strata in northeastern *** results showed that the Ediacaran sediments,without the cap dolomite,unconformably overlaid the Cryogenian sediments in the studied *** Member II of the DST,characterized by 50-160 m of red-green sandstone(approximately equivalent to the original Chengkou“Guanyinya Formation”),directly overlaid the Cryogenian sediments and displayed a 623±2.3 Ma maximum depositional age from the detrital zircon U-Pb *** stratigraphic correlations indicate that the C-E transition strata in northeastern Sichuan had a consistent lithological association and sedimentary sequence characteristics but differed from the Three ***,the upper Nantuo massive glacial diamictites transition to the icebergs rafted lonestone-bearing mudstones at the top,then change upward to DST barrier coast *** proposed DST of the northeastern Sichuan Basin was divided into three lithostratigraphic members without the regional Member I cap dolomite:(i)Member II purple-red,gray-green sandstone strata,(ii)MemberⅢblack mudstone strata,and(iii)Member IV P-Mn bearing *** the C-E transition,the study area experienced(i)the global deglaciation stage in the terminal Marinoan glaciation and(ii)the filling-leveling up stage with clastic rocks in the early ***,the early Ediacaran

关键词： Marinoan glaciation Doushantuo formation Cap dolomite Deglacial and coastal deposits Detrital zircon U-Pb dating

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压气机静叶扇形段制造工艺对气动性能的影响

科学技术与工程 2024年第27期24卷 11891-11900页

作者：敖天翔曹传军中国航发商用航空发动机有限责任公司上海200241

航空发动机高压压气机静子叶片扇形段通常采用机械加工的制造工艺。为降低成本、缩短制造周期,先进航空发动机型号中应用了钣金钎焊的制造工艺批量生产高压压气机静子叶片扇形段。采用钣金钎焊的制造工艺,叶型和流道的几何特征与设计目... 详细信息

航空发动机高压压气机静子叶片扇形段通常采用机械加工的制造工艺。为降低成本、缩短制造周期,先进航空发动机型号中应用了钣金钎焊的制造工艺批量生产高压压气机静子叶片扇形段。采用钣金钎焊的制造工艺,叶型和流道的几何特征与设计目标存在一定的偏差,影响了气动性能。以高负荷十级轴流压气机出口级为研究对象,提出了钣金钎焊制造工艺对气动性能影响的评估方法,评估了钣金钎焊制造工艺对高压压气机性能的影响。结果表明,钣金钎焊制造工艺使得该型压气机流量偏小约1.41%,峰值效率偏低0.41%,其中叶型轮廓度增大是造成性能恶化的主要原因。随叶片轮廓度增大,各级特性都呈现出匹配点压比降低,峰值效率减小的趋势;静叶轮廓度变化对下游转子性能影响较小,压气机性能变化主要是由于静子段损失发生变化导致。

关键词：航空发动机高压压气机数值模拟钣金钎焊轮廓度扭转角

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董事高管责任保险与企业数字化转型

税务与经济 2024年第4期 63-72页

作者：王积田唐必聪田博傲东北农业大学经济管理学院黑龙江哈尔滨150030

董事高管责任保险作为公司治理机制的补充,可能会因其人才虹吸效应和风险兜底效应对企业数字化转型产生影响。利用2010~2021年沪深A股上市公司财务数据,实证检验董事高管责任保险与企业数字化转型之间的关系,研究发现:董事高管责任保险... 详细信息

董事高管责任保险作为公司治理机制的补充,可能会因其人才虹吸效应和风险兜底效应对企业数字化转型产生影响。利用2010~2021年沪深A股上市公司财务数据,实证检验董事高管责任保险与企业数字化转型之间的关系,研究发现:董事高管责任保险的引入能够促进企业数字化转型。作用机制表明,董事高管责任保险主要通过提升企业风险承担水平和人力资本水平来推动企业数字化转型;异质性分析表明,董事高管责任保险对企业数字化转型的促进作用在高新企业以及聘用海归背景高管的企业中更为显著。应持续完善董责险的制度设计,对冲管理者执业风险,促使企业高管积极推进企业数字化转型。

关键词：数字化转型董事高管责任保险风险兜底效应人才虹吸效应

Gamma/Hadron Separation Method for the HADAR Experiment

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Research in Astronomy and Astrophysics 2024年第3期24卷 70-74页

作者： Yang-Zhao Ren tian-Lu Chen You-Liang Feng Dan-Zeng Luo-Bu Yi-Qing Guo Cheng Liu Qi Gao Mao-Yuan Liu Xiang-Li Qian Ya-Ping Wang zi-Hao Zhang Xin-Long Li Qing-Yuan Hou Heng-Jiao Liu Qing-Qian Zhou Shan-Jie Shu The Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences School of Intelligent Engineering Shandong Management University

Ground-based arrays of imaging atmospheric Cherenkov telescopes(IACTs)are the most sensitiveγ-ray detectors for energies of approximately 100 Ge V and *** such IACT is the High Altitude Detection of Astronomical Radiation(HADAR)experiment,which uses a large aperture refractive water lens system to capture atmospheric Cherenkov photons(i.e.,the imaging atmospheric Cherenkov technique).The telescope array has a low threshold energy and large field of view,and can continuously scan the area of the sky being observed,which is conducive to monitoring and promptly responding to transient *** process ofγ-hadron separation is essential in very-high-energy(>30 Ge V)γ-ray astronomy and is a key factor for the successful utilization of *** this study,Monte Carlo simulations were carried out to model the response of cosmic rays within the HADAR *** analyzing the Hillas parameters and the distance between the event core and the telescope,the distinction between air showers initiated byγ-rays and those initiated by cosmic rays was ***,a Quality Factor was introduced to assess the telescope’s ability to suppress the background and to provide a more effective characterization of its performance.

关键词： astroparticle physics-telescopes-methods data analysis

The only purple-flower species in Actaea *** pollinated by a hornet

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Journal of Plant Ecology 2024年第4期17卷 181-196页

作者： Lin-Feng Qiu Jiu-Dong Zhang Ying Li Xiao-Ying Liu Dan-Qing Zhang Long Huang Ya-Peng Yang Shi-Yu Wang Yue-Yi Li zi-Wei Ma Jie Sui Lin Wang Xiao-Fen Che Xian-Hua tian Yi Ren Jian-Qiang Zhang National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China College of Life SciencesShaanxi Normal UniversityXi’an 710119China Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education Shaanxi Normal UniversityXi’an 710119China College of Biological and Environmental Engineering Xi’an UniversityXi’an 710065China

Examining the pollination biology of plant species is not only crucial for enhancing our understanding of their reproductive biology,but also essential for elucidating their adaptation and evolutionary ***,we investigated the breeding system and pollination biology of two closely related species in *** flower of *** is unique in the genus with purple and chartaceous(paper-like)sepals,fewer stamens with yellow anthers and purple *** three seasons of field observation and exclusion experiments,we determined that *** was primarily pollinated by a hornet species,Vespa bicolor,which also served as the most efficient *** contrast,*** was primarily pollinated by large *** purpurea exhibited a significantly higher cumulative nectar volume than ***,which could be a crucial factor in attracting ***.A control experiment further demonstrated that removing the nectar leaf(petal)significantly decreased the visiting frequency of *** system studies revealed that both species were self-compatible,yet they primarily underwent outcrossing in natural *** study presents a compelling case of possible pollinator shift in *** accompanied by morphological divergence.A more in-depth investigation of this system would offer crucial insights into the extent to which pollinators are involved in the plant speciation process and whether they contribute to reproductive isolation between closely related species.

关键词： Actaea purpurea Actaea japonica breeding system pollinator shift speciation Vespa bicolor

Combination of p-Coumaric acid and lactoferrin ameliorates cognitive deficits through suppressing C/EBPβ/AEP pathway and modulating intestinal flora in APP/PS1 mice

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Food Science and Human Wellness 2024年

作者： Yan Zhou Yi-tian Sun Hui Guo Yan-zi Liang Si-Yuan Zhu Yu Sha Zhong-Xiao Wan Jia-Ying Xu Jian-Rong Jiang Li-Qiang Qin Yun-Hong Li Department of Nutrition and Food Hygiene， School of Public Health， Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases， MOE Key Laboratory of Geriatric Diseases and Immunology， Suzhou Medical college of Soochow University Department of Medical Technology， Suzhou Vocational Health College State Key Laboratory of Radiation Medicine and Protection， School of Radiation Medicine and Protection， Suzhou Medical college of Soochow University Suzhou Municipal Center for Disease Control and Prevention

Alzheimer's disease （AD） has become an important public health issue worldwide. P-Coumaric acid （CA） and lactoferrin （Lf） possessed antioxidant， anti-inflammatory， and anti-AD activities. Herein， we hypothesized that a combination treatment of CA and Lf would synergistically improve AD symptoms and studied its mechanisms. Twelve-week-old APP/PS1 mice were treated with CA， Lf， or both CA and Lf for 8 weeks. Results showed that individual and combined treatments could ameliorate cognitive deficits to varying degrees， with stronger effects for combined intervention than for CA or Lf alone. Specifically， combined treatment was most effective in improving nesting ability and reducing Aβ1-42deposition in mice. Moreover， combined treatment was more effective in suppressing APP， BACE1， and inflammation; it inhibited the CCAAT-enhancer-binding protein （C/EBPβ）/asparagine endopeptidase （AEP） signaling pathway in the hippocampus and colon and upregulated the expression of tight junction protein ZO-1 in the colon; it also decreased the F/B ratio at the phylum level and increased the relative abundance of Prevotellaceae， Lachnospira， and Eubacterium at the genus level. Overall， the combination of CA and Lf may ameliorate cognitive deficits in APP/PS1 mice by improving inflammation and inhibiting the C/EBPβ/AEP signaling pathway via modulating gut microbiome.

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支持实时流计算应用的关键技术研究进展

软件学报 2024年第1期35卷 430-454页

作者：徐志榛徐辰丁光耀陈梓浩周傲英华东师范大学数据科学与工程学院上海200062 上海市大数据管理系统工程研究中心上海200062 广西可信软件重点实验室(桂林电子科技大学) 广西桂林541004

信息系统在进行知识的挖掘和管理时,需要处理各种形式的数据,流数据便是其中之一.流数据具有数据规模大、产生速度快且蕴含的知识具有较强时效性等特点,因而发展支持实时处理应用的流计算技术对于信息系统的知识管理十分重要.流计算系... 详细信息

信息系统在进行知识的挖掘和管理时,需要处理各种形式的数据,流数据便是其中之一.流数据具有数据规模大、产生速度快且蕴含的知识具有较强时效性等特点,因而发展支持实时处理应用的流计算技术对于信息系统的知识管理十分重要.流计算系统可以追溯到29世纪90年代,至今已经经历了长足的发展.然而,当前多样化的知识管理需求和新一代的硬件架构为流计算系统带来了全新的挑战和机遇,催生出了一系列流计算领域的技术研究.首先介绍流计算系统的基本需求以及发展脉络,再按照编程接口、执行计划、资源调度和故障容错4个层次分别分析流计算系统领域的相关技术;最后,展望流计算技术在未来可能的研究方向和发展趋势.

关键词：实时处理流计算数据处理系统

All-sky Guide Star Catalog for CSST

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Research in Astronomy and Astrophysics 2024年第4期24卷 35-59页

作者： Hui-Mei Feng zi-Huang Cao Man I Lam Ran Li Hao tian Da-Yi Yin Yuan-Yu Yang Xin Zhang Dong-Wei Fan Yi-Qiao Dong Xin-Feng Li Wei Wang Long Li Hugh RAJones Yi-Han Tao Jia-Lu Nie Pei-Pei Wang Mao-Yuan Liu He-jun Yang Chao Liu Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of ChineseAcademy of Sciences Beijing 100049China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai200083China Technology and Engineering Center for Space Utilization.Chinese Academy of Sciences Beijing 100094China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Centre for Astrophysics University of HertfordshireHatfieldUK Beijing University of Technology Beijing 100124China

The China Space Station Telescope(CSST)is a two-meter space telescope with multiple back-end *** Fine Guidance Sensor(FGS)is an essential subsystem of the CSST Precision Image Stability System to ensure the required absolute pointing accuracy and line-of-sight *** this study,we construct the Main Guide Star Catalog for *** accomplish this,we utilize the information about the FGS and object information from the Gaia Data Release *** provide an FGS instrument magnitude and exclude variables,binaries,and high proper motion stars from the catalog to ensure uniform FGS guidance ***,we generate a HEALPix index,which provides a hierarchical tessellation of the celestial sphere,and employ the Voronoi algorithm to achieve a homogeneous distribution of stars across the *** distribution ensures adequate coverage and sampling of the *** performance of the CSST guide star catalog was assessed by simulating the field of view of the FGS according to the CSST mock survey strategy *** analysis of the results indicates that this catalog provides adequate coverage and *** catalog's performance meets the FGS requirements,ensuring the functioning of the FGS and its guidance capabilities.

关键词： catalogs astrometry instrumentation:detectors

Artificial cavernosa-like tissue based on multibubble Matrigel and a human corpus cavernous fibroblast scaffold

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Asian Journal of Andrology 2024年第3期26卷 260-267页

作者： Yu-Zhuo Chen Yi-Hong Zhou Min-Bo Yan Ming Xiao Biao Liu Ying-Hao Yin Xiao-Li Tan Yong-Quan Huang Yu-Hong Lin Ting Xie Jia-Li tian Qi Wang Jian-Ying Li zi-Zhou Meng Zheng Li Emily Xing Yu-Xin Tang Ya-Wei Li Zhong-Zhen Su Liang-Yu Zhao Department of Ultrasound The Fifth Affiliated HospitalSun Yat-sen UniversityZhuhai 519000China Department of Interventional Medicine Guangdong Provincial Key Laboratory of Biomedical ImagingThe Fifth Affiliated HospitalSun Yat-sen UniversityZhuhai 519000China Department of Urology The Fifth Affiliated HospitalSun Yat-sen UniversityZhuhai 519000China Department of Andrology the Center for Men’s HealthUrologic Medical CenterShanghai Key Laboratory of ReproductiveMedicineShanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China Cedars-Sinai Medical Center Los AngelesCA 90024USA

Ex vivo tissue culture of the human corpus cavernosum(cc)can be used to explore the tissue structural changes and complex signaling *** present,artificial Cc-like tissues based on acellular or three-dimensional(3D)-printed scaffolds are used to solve the scarcity of primary penis tissue ***,inconvenience and high costs limit the wide application of such ***,we describe a simple,fast,and economical method of constructing artificial CC-like *** Cc fibroblasts(FBs),endothelial cells(ECs),and smooth muscle cells(SMCs)were expanded in vitro and mixed with Matrigel in specific proportions.A large number of bubbles were formed in the mixture by vortexing combined with pipette blowing,creating a porous,spongy,and spatial *** Cc FBs produced a variety of signaling factors,showed multidirectional differentiation potential,and grew in a 3D grid in Matrigel,which is necessary for CC-like tissue to maintain a porous structure as a cell *** the C-like tissue,ECs covered the surface of the lumen,and SMCs were located inside the trabeculae,similar to the structure of the primary *** cell components remained stable for 3 days in vitro,but the EC content decreased on the 7th ***/integrated(WNT)signaling activation led to lumen atrophy and increased tissue fibrosis in CC-like tissue,inducing the same changes in characteristics as in the primary *** study describes a preparation method for human artificial cC-like tissue that may provide an improved experimental platform for exploring the function and structure of the cC and conducting drug screening for erectile dysfunction therapy.

关键词： artificial tissue corpus cavernosum ex vivo fibroblasts