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Mars exploration——In situ K-Ar dating of jarosite

Science China Earth Sciences 2024年第3期67卷 641-656页

作者： jing yaNG Dewen ZHENG Ying WU Hong chen Li yaNG Bin ZHANG Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesInstitute of GeomechanicsChinese Academy of Geological SciencesBeijing 100081China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Institute of Earth Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029Chin

To accurately determine the chronological framework of climatic variations recorded by various Martian terrains, the absolute ages of Martian events and cratering rate need to be constrained by either in situ dating or returned samples. In situ K-Ar dating is currently a more plausible dating technique as compared with sample return. Jarosite(KFe_(3)[SO_(4)]_(2)[OH]_(6)) is the only confirmed K sulfate mineral that is widely present on Mars, as indicated by in situ detection, orbital remote sensing, and meteorite studies. Jarosite can be used for precise K-Ar and (40)Ar/(39)Ar dating. The preservation of jarosite on Mars provides information about the nature and duration of aqueous processes on the Martian surface. Different ages of Martian jarosite represent the key to constraining the transition from Martian surface water activity to arid climatic conditions. This paper summarizes recent advances in our knowledge of the spatial distribution of Martian jarosite, its mineralogical properties and stability on Mars, the Ar diffusion kinetics of jarosite, and the current status of in situ K-Ar dating. Moreover, we examine the key scientific issues to be addressed for in situ K-Ar dating of jarosite and Martian sample return missions, and discuss future research directions.

关键词： Mars Jarosite In situ K-Ar dating Ar diffusion Stability

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A buffer overflow detection and defense method based on RiSC-V instruction set extension

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Cybersecurity 2024年第2期7卷 28-43页

作者： Chang Liu yan-Jun Wu jing-Zheng Wu chen Zhao Intelligent Software Research Center Institute of SoftwareChinese Academy of SciencesBejingChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijingChina

Buffer overflow poses a serious threat to the memory security of modern operating *** overwrites the con-tents of other memory areas by breaking through the buffer capacity limit,destroys the system execution environ-ment,and provides implementation space for various system attacks such as program control flow *** makes it a wide range of harms.A variety of security technologies have been proposed to deal with system security problems including buffer *** example,No eXecute(NX for short)is a memory management technology commonly used in Harvard *** can refuse the execution of code which residing in a specific memory,and can effectively suppress the abnormal impact of buffer overflow on control ***,in recent years,it has also been used in the field of system security,deriving a series of solutions based on NX technology,such as ExecShield,DEP,StackGuard,***,these security solutions often rely too much on the processor archi-tecture so that the protection coverage is insufficient and the accuracy is *** in the emerging system architecture field represented by RiSC-V,there is still a lack of effective solutions for buffer overflow *** the continuous rapid development of the system architecture,it is urgent to develop defense methods that are applicable to different system application environments and oriented to all executable memory spaces to meet the needs of system security ***,we propose BOP,A new system memory security design method based on RISC-V extended instructions,to build a RISC-V buffer overflow detection and defense system and deal with the buffer overflow threat in *** to this method,NX technology can be combined with program control flow analysis,and Nx bit mechanism can be used to manage the executability of memory space,so as to achieve a more granular detection and defense of buffer overflow attacks that may occur in RISC-V system

关键词： RISc-V Operating system security Buffer overflow Control flow hijacking Nx bit Xibop

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A novel structural variant of RET causes familial Hirschsprung's disease via nonsense-mediated mRNA decay

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Genes & Diseases 2024年第1期11卷 7-10页

作者： Qi Wang Siyu Pu Bo Xiang jing chen Department of Pediatric Surgery and Laboratory of Pediatric Surgery Rare Diseases CenterInstitute of Immunology and InflammationFrontiers Science Center for Disease-Related Molecular NetworkWest China HospitalSichuan UniversityChengduSichuan 610041China

Hirschsprung's disease(HsCR)is the most common type of developmental gastrointestinal malformation causing intestinal obstruction in children,with an incidence of 1/5000 in live births.1 it is characterized by the absence of intrinsic ganglion cells in the myenteric and submucosal plexuses of the distal gastrointestinal tract,leading to the dysregulation of smooth muscle contraction/relaxation and resulting in intestinal *** on the length of the aganglionic intestine,HSCR can be categorized into short-segmental HSCR(S-HSCR),which affects up to the sigmoid colon from the anus,and long-segmental HSCR(LHSCR),which affects beyond the sigmoid colon.1 In some rare conditions,aganglionic lesions can affect the full length of the colon or even the whole intestine.

关键词： intestine colon relaxation

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Effects of different orthokeratology lens designs on slowing axial length elongation in children with myopia

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1843-1849页

作者： Hai-Long Ni Xiang chen Du-ya chen Pei-Ke Hu Zhi-Yi Wu Eye Center the Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

AIM:To elucidate whether differences exist in the impact on retarding the elongation of axial length(AL)among children with myopia when utilizing orthokeratology(ortho-k)lenses employing the corneal refractive therapy(CRT)design versus those employing the vision shaping treatment(VST)***:This retrospective clinical trial aimed to collect and analyze AL data from individuals who wore ortho-k lenses for three years.A total of 654 subjects were enrolled and prescribed one of the three specific brands of ortho-k lenses:CRT,Euclid,and *** study’s primary focus was to compare the rates of AL elongation and myopic progression across these three brands of ortho-k ***:In the 3-year follow-up,the AL elongation exhibited variations of 0.73±0.36 mm in the CRT lens group,0.59±0.37 mm in the Euclid lens group,and 0.63±0.38 mm in the Mouldway lens group.A noteworthy disparity emerged between the CRT and Mouldway groups(P<0.01),as well as between the CRT and Euclid groups(P<0.001).Additionally,it was observed that 32.1%of participants who wore CRT lenses experienced a decelerated progression of myopia,in contrast to 47.2%in the Euclid group and 44.4%in the Mouldway *** analyses revealed a statistically significant distinction between the CRT and Euclid groups(P<0.01),and similarly,the CRT group demonstrated a statistically significant difference when compared to the Mouldway group(P<0.05).CONCLUSION:Ortho-k lenses represent a pragmatic strategy for mitigating the advancement of *** contradistinction to ortho-k lenses utilizing the CRT design,those employing the VST design exhibited a more favorable impact regarding retarding AL elongation.

关键词： myopia orthokeratology design axial length

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Privacy-Preserving Multi-Keyword Fuzzy Adjacency Search Strategy for Encrypted Graph in Cloud Environment

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Computers, Materials & Continua 2024年第3期78卷 3177-3194页

作者： Bin Wu Xianyi chen Jinzhou Huang Caicai Zhang jing Wang jing Yu Zhiqiang Zhao Zhuolin Mei School of Computer and Big Data Science Jiujiang UniversityJiujiang332005China Jiujiang Key Laboratory of Network and Information Security Jiujiang332005China School of Computer and Software Nanjing University of Information Science&TechnologyNanjing210044China School of Computer Engineering Hubei University of Arts and ScienceXiangyang441053China School of Modern Information Technology Zhejiang Institute of Mechanical and Electrical EngineeringHangzhou310053China Information Center Jiangxi Changjiang Chemical Co.Ltd.Jiujiang332005China School of Mathematics and Computer Science Ningxia Normal UniversityGuyuan756099China

In a cloud environment,outsourced graph data is widely used in companies,enterprises,medical institutions,and so *** owners and users can save costs and improve efficiency by storing large amounts of graph data on cloud *** on cloud platforms usually have some subjective or objective attacks,which make the outsourced graph data in an insecure *** issue of privacy data protection has become an important obstacle to data sharing and *** to query outsourcing graph data safely and effectively has become the focus of *** query is a basic and frequently used operation in graph,and it will effectively promote the query range and query ability if multi-keyword fuzzy search can be supported at the same *** work proposes to protect the privacy information of outsourcing graph data by encryption,mainly studies the problem of multi-keyword fuzzy adjacency query,and puts forward a *** our scheme,we use the Bloom filter and encryption mechanism to build a secure index and query token,and adjacency queries are implemented through indexes and query tokens on the cloud *** proposed scheme is proved by formal analysis,and the performance and effectiveness of the scheme are illustrated by experimental *** research results of this work will provide solid theoretical and technical support for the further popularization and application of encrypted graph data processing technology.

关键词： Privacy-preserving adjacency query multi-keyword fuzzy search encrypted graph

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Dynamic steric confinement effect expands the frontier of Cu-catalyzed asymmetric propargylic aminations

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Science China Chemistry 2024年第10期67卷 3181-3183页

作者： Peng chen Mao-Mao Zhang Wen-jing Xiao Liang-Qiu Lu Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079China Wuhan Institute of Photochemistry and Technology Wuhan 430082China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics(LICP)Chinese Academy of SciencesLanzhou 730000China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

Chiralα-tertiary amines and related azacycles are commonly found in many natural products,pharmaceuticals and agrochemicals[1].Copper-catalyzed asymmetric propargylic amination(APA)reactions have been established as a reliable method to access enantio-enriched propargylic amines,largely due to the seminal contribution of Nishibayashi et al.[2]and van Maarseveen et al.[3]in 2008.

关键词： catalyzed asymmetric amines

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Asymmetric radical allylation of β-keto esters with vinyl cyclopropanes by dual photoredox/nickel catalysis

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Science China Chemistry 2024年第11期67卷 3807-3816页

作者： Wen-Yuan Qu Xue-Song Zhou Wen-jing Xiao Jia-Rong chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of Chemistry Central China Normal University Wuhan Institute of Photochemistry and Technology Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal University

Radical-involved allylation reactions have emerged as a powerful platform for construction of carbon-carbon and carbonheteroatom bonds, facilitating the strategic incorporation of diverse allyl moieties. Nevertheless, this burgeoning field still faces ongoing challenges, including limitations of radical precursors and coupling partners, and difficulties in achieving enantiocontrol. Herein, we report for the first time a highly enantioselective radical allylation involving β-keto esters with vinyl cyclopropanes utilizing a synergistic dual photoredox/nickel catalysis under visible light irradiation. The mild and redox-neutral catalytic protocol demonstrates an extensive substrate compatibility and good functional tolerance, providing access to enantioenriched β-keto esters featuring quaternary α-stereocenter with good yields and high enantioselectivities. Preliminary mechanistic studies have uncovered that the success of the reaction hinges on the dual roles of nickel catalyst, including in situ formation of photoredox sensitive substrate/Ni complex and the ensuing asymmetric radical addition step.

关键词： asymmetric allylation photoredox catalysis radical addition nickel catalysis β-keto esters vinyl cyclopropanes

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Photocaged activity-based probes for improved monitoring of protein S-sulfenylation in living cells

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Chinese Chemical Letters 2024年第2期35卷 451-454页

作者： Jiahao Zhang Haiyue Peng Zi'an chen Guorui Li jing Huang State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan Provincial Key Laboratory of Animal Models and Molecular MedicineSchool of Biomedical SciencesHunan UniversityChangsha 410082China

Protein S-sulfenylation(protein sulfenic acid),as one of the most significant oxidative post-translational modifications(OxiPTMs),plays a vital role in regulating protein function.A variety of activity-based probes have been developed to profile sulfenic acid in living ***,due to the transient presence and low content of sulfenic acid in living cell,high doses of probes are needed to achieve efficient *** importantly,current probes have no temporal control over sulfenic acid *** overcome these limitations,two caged cysteine sulfenic acid probes DYn-2-ONB and DYn-2-Cou with either an o-nitrobenzyl or coumarin protecting group were developed in this *** probes can be efficiently uncaged via irradiation to produce the active C-nucleophile probe *** assay in living cells demonstrated DYn-2-ONB exhibited better labeling capacity compared with DYn-2,providing it as a powerful tool for improved monitoring of protein S-sulfenylation in living cells.

关键词： Cysteine Sulfenic acid Activity-based probe Photocage Light activation Protein S-sulfenylation

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Cultivating the uncultured:Harnessing the“sandwich agar plate”approach to isolate heme-dependent bacteria from marine sediment

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mLife 2024年第1期3卷 143-155页

作者： jing Zhang Qi-Yun Liang Da-Shuai Mu Fengbai Lian ya Gong Mengqi Ye Guan-Jun chen Yuqi Ye Zong-Jun Du State Key Laboratory of Microbial Techlogy Insttute of Micrbial TchnoogyShandong UniversityQingdaoChina Marine College Shandong UniverstyWeihaiChina Shandong University-Weihai Research Institute of Industrial Technology WeihaiChina

In the classical microbial isolation technique,the isolation process inevitably destroys all microbial interactions and thus makes it difficult to culture the many microorganisms that rely on these interactions for *** this study,we designed a simple coculture technique named the“sandwich agar plate method,”which maintains microbial interactions throughout the isolation and pure culture *** total yield of uncultured species in sandwich agar plates based on eight helper strains was almost 10-fold that of the control *** uncultured species displayed commensal *** study found that heme was the growth-promoting factor of some marine commensal *** genomic analysis revealed that heme auxotrophies were common in various biotopes and prevalent in many uncultured microbial ***,our study supported that the survival strategies of heme auxotrophy in different habitats varied *** findings highlight that cocultivation based on the“sandwich agar plate method”could be developed and used to isolate more uncultured bacteria.

关键词： cultivation growth factors heme sandwich agar plate uncultured bacteria

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Communication-Aware Mobile Relaying via an AUV for Minimal Wait Time:A Broad Learning-Based Solution

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 797-799页

作者： Wenqiang Cao jing yan Xian yang Cailian chen Xinping Guan the Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004China IEEE the Institute of Information Science and Engineering Yanshan UniversityQinhuangdao 066004China the Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China

Dear Editor,This letter studies the communication-aware mobile relaying via an autonomous underwater vehicle(AUV)for minimal wait *** with the analysis-based channel prediction solution,the proposed discrete Kirchhoff... 详细信息

关键词： underwater autonomous estimation

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