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Utility of fluid inclusion paleo-temperature in petroleum system modelling:A case study from western offshore,India
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作者 V.Nandakumar S.Shivapriya Silpa Thankan 《Energy Geoscience》 EI 2024年第2期101-119,共19页
The paleo-temperature(Th)data from fluid inclusions are utilized for thermal history modelling using PetroMod software.Generally,bottom hole temperature(BHT)and vitrinite reflectance(Ro)measurements are widely used in... The paleo-temperature(Th)data from fluid inclusions are utilized for thermal history modelling using PetroMod software.Generally,bottom hole temperature(BHT)and vitrinite reflectance(Ro)measurements are widely used in petroleum system modelling(PSM)in the oil industry for calibration purposes.Th representing the minimum temperature of fluid entrapment estimated from fluid-inclusion study provides extra support to build the thermal models for PSM.Fluid inclusion parameters along with Rock-Eval pyrolysis analysis have been used to predict the maturity of oil in terms of API gravity as well as the maturity of source rocks respectively.Two exploratory wells RV-1(Mumbai Offshore Basin)and KK4C-A-1(Kerala-Konkan Offshore Basin),India were examined and the T_(h)from most of the fluid inclusions of wells RV-1 and KK4C-A-1 fell in the oil window range of 60-140℃suggesting thermal conditions favourable for oil generation in both of the wells.T_(h)of coeval aqueous inclusions along with the Hydrocarbon Fluid inclusions(HCFIs)was used to calibrate PSM.Vital parameters show that source rocks of well RV-1 are mature and that of well KK4C-A-1 are immature.Two sets of PSM are created in terms of generation and expulsion for the dry wells RV-1 and KK4C-A-1 and calibrated each well using fluid inclusion Th and BHT.From the fluid inclusion analysis method,it is evident that hydrocarbon generation happened in both wells and the paleo-temperature indicates that the formations of both wells were subjected to temperatures in the oil window range,even though it was designated as dry wells in the present scenario.The present study highlights the application of fluid inclusion paleo-temperature(Th)during calibration instead of commonly used methods.We could obtain desirable and accurate data output from PSM using T_(h) calibration. 展开更多
关键词 paleo-temperature(T_(h)) Hydrocarbon fluid inclusion Petroleum system modelling Petroleum generation and expulsion Western offshore basin
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The relationship between proxy decision-making content and cues by families of patients with malignant brain tumor: A descriptive qualitative study
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作者 Runa Tokunaga Fumiyo Ishikawa 《International Journal of Nursing Sciences》 2025年第2期169-175,共7页
Objectives This study aimed to clarify the relationship between the content of proxy decision-making made by families of patients with malignant brain tumors regarding treatment policies and daily care and the cues le... Objectives This study aimed to clarify the relationship between the content of proxy decision-making made by families of patients with malignant brain tumors regarding treatment policies and daily care and the cues leading to those decisions.Methods Semi-structured personal interviews were used to collect data.Seven family members of patients with malignant brain tumors were selected to participate in the study by purposive sampling method from June to August 2022 in the Patient Family Association of Japan.Responses were content analyzed to explore the relationship between the content of decisions regarding“treatment policies”and“daily care”and the cues influencing those decisions.Semi-structured interviews were analyzed by using thematic analysis.Results The contents of proxy decisions regarding“treatment policies”included implementation,interruption,and termination of initial treatments,free medical treatments,use of respirators,and end-of-life sedation and included six cues:treatment policies suggested by the primary physician,information and knowledge about the disease and treatment obtained by the family from limited resources,perceived life threat from symptom worsening,words and reactions from the patient regarding treatment,patient’s personality and way of life inferred from their treatment preferences,family’s thoughts and values hoping for better treatment for the patient.Decisions for“daily care”included meal content and methods,excretion,mobility,maintaining cleanliness,rehabilitation,continuation or resignation from work,treatment settings(outpatient or inpatient),and ways to spend time outside and included seven cues:words and thoughts from the patient about their way of life,patient’s reactions and life history inferred from their preferred way of living,things the patient can do to maintain daily life and roles,awareness of the increasing inability to do things in daily life,family’s underlying thoughts and values about how to spend the remaining time,approval from family members regarding the care setting,advice from medical professionals on living at home.Conclusions For“treatment policies,”guidelines from medical professionals were a key cue,while for“daily care,”the small signs from the patients in their daily lives served as cues for proxy decision-making.This may be due to the lack of information available to families and the limited time available for discussion with the patient.Families of patients with malignant brain tumors repeatedly use multiple cues to make proxy decision-making under high uncertainty.Therefore,nurses supporting proxy decision-making should assess the family’s situation and provide cues that facilitate informed and confident decisions. 展开更多
关键词 Brain neoplasms FAMILY Nurses CUES proxy decision-making
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Blockchain-Enabled Data Secure Sharing with Privacy Protection Based on Proxy Re-Encryption in Web3.0 Applications
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作者 Ma Jiawei Zhou Haojie +2 位作者 Wang Sidie Song Jiyuan Tian Tian 《China Communications》 2025年第5期256-272,共17页
With the rapid development of web3.0 applications,the volume of data sharing is increasing,the inefficiency of big data file sharing and the problem of data privacy leakage are becoming more and more prominent,and the... With the rapid development of web3.0 applications,the volume of data sharing is increasing,the inefficiency of big data file sharing and the problem of data privacy leakage are becoming more and more prominent,and the existing data sharing schemes have been difficult to meet the growing demand for data sharing,this paper aims at exploring a secure,efficient and privacy-protecting data sharing scheme under web3.0 applications.Specifically,this paper adopts interplanetary file system(IPFS)technology to realize the storage of large data files to solve the problem of blockchain storage capacity limitation,and utilizes ciphertext policy attribute-based encryption(CP-ABE)and proxy re-encryption(PRE)technology to realize secure multi-party sharing and finegrained access control of data.This paper provides the detailed algorithm design and implementation of data sharing phases and processes,and analyzes the algorithms from the perspectives of security,privacy protection,and performance. 展开更多
关键词 blockchain data sharing privacy protection proxy re-encryption WEB3.0
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Weighted Attribute Based Conditional Proxy Re-Encryption in the Cloud
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作者 Xixi Yan Jing Zhang Pengyu Cheng 《Computers, Materials & Continua》 2025年第4期1399-1414,共16页
Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribu... Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribute-based conditional proxy re-encryption(AB-CPRE)schemes proposed so far do not take into account the importance of user attributes.A weighted attribute-based conditional proxy re-encryption(WAB-CPRE)scheme is thus designed to provide more precise decryption rights delegation.By introducing the concept of weight attributes,the quantity of system attributes managed by the server is reduced greatly.At the same time,a weighted tree structure is constructed to simplify the expression of access structure effectively.With conditional proxy re-encryption,large amounts of data and complex computations are outsourced to cloud servers,so the data owner(DO)can revoke the user’s decryption rights directly with minimal costs.The scheme proposed achieves security against chosen plaintext attacks(CPA).Experimental simulation results demonstrated that the decryption time is within 6–9 ms,and it has a significant reduction in communication and computation cost on the user side with better functionality compared to other related schemes,which enables users to access cloud data on devices with limited resources. 展开更多
关键词 Cloud service conditional proxy re-encryption user revocation weighted attribute
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Are Elemental Salinity Proxies Worth Their Salt?
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作者 Thomas J.Algeo Wei Wei +2 位作者 Zhanhong Liu Yi Song Huyue Song 《Journal of Earth Science》 2025年第4期1848-1852,共5页
Salinity is a fundamental variable of watermass chemistry,often varying strongly in coastal,estuarine,lagoonal,restricted-marine basinal,and non-freshwater lacustrine systems(Figure 1).Salinity variation commonly cont... Salinity is a fundamental variable of watermass chemistry,often varying strongly in coastal,estuarine,lagoonal,restricted-marine basinal,and non-freshwater lacustrine systems(Figure 1).Salinity variation commonly controls other watermass properties(e.g.,redox,temperature,p H,and chemical composition)as well as nutrient levels(and thus bioproductivity). 展开更多
关键词 PROXIES SALINITY estuarine systems lagoonal systems temperature non freshwater lacustrine systems redox coastal systems
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货币政策的不确定性、宏观经济波动与银行系统金融风险——基于政策不确定性指标不同测度和Proxy-SVAR实证方法的研究 被引量:1
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作者 陆前进 李欣 李晓康 《上海经济研究》 CSSCI 北大核心 2024年第12期101-116,共16页
建立了一个中等规模的结构向量自回归模型,系统探讨了货币政策不确定性对宏观经济波动与银行系统金融风险的影响。首先,比较现阶段我国主流货币政策不确定性及经济政策不确定性代理指标,发现Huang&Luk (2020)所测度MPU与EPU并不能... 建立了一个中等规模的结构向量自回归模型,系统探讨了货币政策不确定性对宏观经济波动与银行系统金融风险的影响。首先,比较现阶段我国主流货币政策不确定性及经济政策不确定性代理指标,发现Huang&Luk (2020)所测度MPU与EPU并不能对我国宏观经济波动做出较好解释。比较而言,Baker et al.(2016)与Davis et al.(2019)的EPU对我国宏观经济波动影响更符合预期,EPU的影响类似于紧缩性供给冲击,导致产出、固定资产投资以及社会零售消费降低,通货膨胀上升。特别是在EPU_Davis指标存在意外正向冲击时,可能导致银行系统金融风险上升。其次,利用条件波动率思想,重新估计货币政策不确定性(MPU_Volatility),发现无论是简约形式或结构形式估计,所获得MPU_Volatility在波动趋势上大体一致,且MPU_Volatility与EPU_Baker及EPU_Davis对宏观经济作用效果存在较大一致,其中MPU_Volatility与EPU_Davis对银行系统金融风险影响一致。最后,进一步将叙事性EPU_Davis指标与MPU_Volatility结合使用,选用Proxy SVAR对货币政策不确定性结构冲击进行识别,这保证了即使存在测量误差情况下,估计偏误也会大幅降低。实证发现MPU对宏观经济变量造成不利影响,导致银行系统金融风险上升并持续较长时间。脉冲响应结果与EPU_Davis及MPU_Volatility结果相似,这一定程度上支持之前结论的稳健。 展开更多
关键词 货币政策不确定性 银行系统金融风险 虚拟变量结构向量自回归 结构冲击识别 测量误差
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Paleo-temperature Evolution and Water Soluble Gas in Sinian Reservoir, Anpingdian-Gaoshiti Structural Zone, Central Sichuan Basin 被引量:3
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作者 袁海锋 徐国盛 +1 位作者 刘树根 王国芝 《Journal of China University of Geosciences》 SCIE CSCD 2008年第6期707-714,共8页
The paleo-temperature evolution of Sinian reservoir of Anping (安平) 1 well was rebuilt by taking the method of apatite fission track and Easy%Ro model. The result of apatite fission track determines the accurate bu... The paleo-temperature evolution of Sinian reservoir of Anping (安平) 1 well was rebuilt by taking the method of apatite fission track and Easy%Ro model. The result of apatite fission track determines the accurate burial history and overcomes the flaw that the vitrinite reflectance is taken as paleo-temperature indicator simply. The authors used the laser Raman technique to analyze the methane present in the calcite and quartz fluid inclusions of Sinian reservoir, finding that the methane is water soluble gas. The authors also simulated the paleo-pressure of fluid inclusion by using PVTsim software and finally worked out the methane solubility in water. 展开更多
关键词 Central Sichuan (四川) basin Anpingdian (安平店)-Gaoshiti (高石梯) structural zone paleo-temperature apatite fission track fluid inclusion water soluble gas
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A Blockchain-Based Proxy Re-Encryption Scheme with Conditional Privacy Protection and Auditability
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作者 Chen Guo PengWeijun +3 位作者 Wu Jing Fang Youxuan Ye Keke Xin Yanshuang 《China Communications》 SCIE CSCD 2024年第7期267-277,共11页
With the development of Internet of Things technology,intelligent door lock devices are widely used in the field of house leasing.In the traditional housing leasing scenario,problems of door lock information disclosur... With the development of Internet of Things technology,intelligent door lock devices are widely used in the field of house leasing.In the traditional housing leasing scenario,problems of door lock information disclosure,tenant privacy disclosure and rental contract disputes frequently occur,and the security,fairness and auditability of the housing leasing transaction cannot be guaranteed.To solve the above problems,a blockchain-based proxy re-encryption scheme with conditional privacy protection and auditability is proposed.The scheme implements fine-grained access control of door lock data based on attribute encryption technology with policy hiding,and uses proxy re-encryption technology to achieve auditable supervision of door lock information transactions.Homomorphic encryption technology and zero-knowledge proof technology are introduced to ensure the confidentiality of housing rent information and the fairness of rent payment.To construct a decentralized housing lease transaction architecture,the scheme realizes the efficient collaboration between the door lock data ciphertext stored under the chain and the key information ciphertext on the chain based on the blockchain and InterPlanetary File System.Finally,the security proof and computing performance analysis of the proposed scheme are carried out.The results show that the scheme can resist the chosen plaintext attack and has low computational cost. 展开更多
关键词 attribute encryption blockchain homomorphic encryption house leasing proxy re-encryption zero-knowledge proof
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Quantum circuit-based proxy blind signatures:A novel approach and experimental evaluation on the IBM quantum cloud platform
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作者 娄小平 昝慧茹 徐雪娇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期247-253,共7页
This paper presents a novel approach to proxy blind signatures in the realm of quantum circuits,aiming to enhance security while safeguarding sensitive information.The main objective of this research is to introduce a... This paper presents a novel approach to proxy blind signatures in the realm of quantum circuits,aiming to enhance security while safeguarding sensitive information.The main objective of this research is to introduce a quantum proxy blind signature(QPBS)protocol that utilizes quantum logical gates and quantum measurement techniques.The QPBS protocol is constructed by the initial phase,proximal blinding message phase,remote authorization and signature phase,remote validation,and de-blinding phase.This innovative design ensures a secure mechanism for signing documents without revealing the content to the proxy signer,providing practical security authentication in a quantum environment under the assumption that the CNOT gates are securely implemented.Unlike existing approaches,our proposed QPBS protocol eliminates the need for quantum entanglement preparation,thus simplifying the implementation process.To assess the effectiveness and robustness of the QPBS protocol,we conduct comprehensive simulation studies in both ideal and noisy quantum environments on the IBM quantum cloud platform.The results demonstrate the superior performance of the QPBS algorithm,highlighting its resilience against repudiation and forgeability,which are key security concerns in the realm of proxy blind signatures.Furthermore,we have established authentic security thresholds(82.102%)in the presence of real noise,thereby emphasizing the practicality of our proposed solution. 展开更多
关键词 proxy blind signature quantum circuits quantum computation IBM quantum cloud platform
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Quantum-Resistant Multi-Feature Attribute-Based Proxy Re-Encryption Scheme for Cloud Services
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作者 Jinqiu Hou Changgen Peng +1 位作者 Weijie Tan Hongfa Ding 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期917-938,共22页
Cloud-based services have powerful storage functions and can provide accurate computation.However,the question of how to guarantee cloud-based services access control and achieve data sharing security has always been ... Cloud-based services have powerful storage functions and can provide accurate computation.However,the question of how to guarantee cloud-based services access control and achieve data sharing security has always been a research highlight.Although the attribute-based proxy re-encryption(ABPRE)schemes based on number theory can solve this problem,it is still difficult to resist quantum attacks and have limited expression capabilities.To address these issues,we present a novel linear secret sharing schemes(LSSS)matrix-based ABPRE scheme with the fine-grained policy on the lattice in the research.Additionally,to detect the activities of illegal proxies,homomorphic signature(HS)technology is introduced to realize the verifiability of re-encryption.Moreover,the non-interactivity,unidirectionality,proxy transparency,multi-use,and anti-quantum attack characteristics of our system are all advantageous.Besides,it can efficiently prevent the loss of processing power brought on by repetitive authorisation and can enable precise and safe data sharing in the cloud.Furthermore,under the standard model,the proposed learning with errors(LWE)-based scheme was proven to be IND-sCPA secure. 展开更多
关键词 LATTICE learning with errors attribute-based proxy re-encryption linear secret sharing schemes
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基于混合物理数据驱动的油藏地质体CO_(2)利用与封存代理模型研究 被引量:3
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作者 芮振华 邓海洋 胡婷 《钻采工艺》 北大核心 2025年第1期190-198,共9页
在全球能源转型与能源需求持续增长的背景下,碳捕获、利用和封存(CCUS)已成为极具前景的研究方向。CO_(2)利用与封存协同优化通常依赖大量的组分正演模拟,但三维高分辨率模型计算成本高昂,限制其广泛应用。基于混合物理数据驱动的GPSNe... 在全球能源转型与能源需求持续增长的背景下,碳捕获、利用和封存(CCUS)已成为极具前景的研究方向。CO_(2)利用与封存协同优化通常依赖大量的组分正演模拟,但三维高分辨率模型计算成本高昂,限制其广泛应用。基于混合物理数据驱动的GPSNet模型以其高效的计算效率已成为一种理想的代理模型,然而现有的GPSNet模型难以准确捕获复杂的相行为和组分间的相互作用,为此,文章提出了一种新型专用于组分模拟的comp-GPSNet模型,通过标准失配最小化方法和基于伴随的梯度优化算法对comp-GPSNet模型进行训练,以拟合从高分辨率模拟中获取的井响应数据。将训练后的模型应用到PUNQ-S3油藏中,全面评估复杂条件下comp-GPSNet模型的预测能力,结果表明,comp-GPSNet模型在单井和区块范围内均表现出良好的预测精度,CO_(2)利用率和封存率的预测误差分别为0.16%和3.13%。该模型为CO_(2)利用与封存协同优化提供了一个稳健的代理框架,以推动油田数字化与智能化发展。 展开更多
关键词 CCUS comp-GPSNet 混合物理数据驱动 代理模型 组分模拟
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测井旋回地层学研究现状与发展方向 被引量:1
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作者 彭诚 邹长春 曹金彧 《测井技术》 2025年第2期139-151,共13页
测井旋回地层学对地球物理测井数据记录的天文旋回进行识别、提取与解释,已成为研究地球科学领域诸多关键科学问题的基础。通过梳理旋回地层学研究需求与地球物理测井数据特点,剖析测井旋回地层学的发展动力;通过回顾国内外古气候测井... 测井旋回地层学对地球物理测井数据记录的天文旋回进行识别、提取与解释,已成为研究地球科学领域诸多关键科学问题的基础。通过梳理旋回地层学研究需求与地球物理测井数据特点,剖析测井旋回地层学的发展动力;通过回顾国内外古气候测井替代指标、天文旋回分析方法等方面的研究成果,分析其发展现状;结合地球科学领域的发展态势,探讨其未来发展方向。尽管大部分测井技术是以油气勘探开发为目的发展而来,但其测量数据连续、高分辨率、多参数等优势使其成为研究轨道驱动古气候的重要手段。目前,常规测井、自然伽马能谱测井与电成像测井等数据已经在旋回地层学研究中得到了成功应用;测井数据在轨道尺度气候响应机理、测井天文旋回识别与替代指标敏感性评价方法等研究方面也取得了诸多进展。未来,基于成像测井数据的替代指标发展、多参数联合分析方法的建立、智能化处理与大数据分析手段的引入等,将进一步挖掘测井旋回地层学在深时研究、油气勘探等领域的应用潜力。 展开更多
关键词 测井旋回地层学 米兰科维奇旋回 替代指标 古气候 深时
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晚期癌症患者代理决策者决策困境现状及影响因素研究 被引量:2
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作者 崔晓薇 张艳洪 +3 位作者 韩吉华 张馨 吴羡美 王彤 《护理管理杂志》 2025年第3期225-230,共6页
目的 调查晚期癌症患者代理决策者决策困境现状并分析其影响因素,满足代理决策者信息需求,提高其决策能力和应对能力。方法 采用便利抽样法,选取2023年12月至2024年2月哈尔滨某肿瘤医院治疗的晚期癌症患者的代理决策者为研究对象,采用... 目的 调查晚期癌症患者代理决策者决策困境现状并分析其影响因素,满足代理决策者信息需求,提高其决策能力和应对能力。方法 采用便利抽样法,选取2023年12月至2024年2月哈尔滨某肿瘤医院治疗的晚期癌症患者的代理决策者为研究对象,采用一般资料调查表、决策困境量表、决策疲劳量表、维克森林医师信任量表及社会支持评定量表进行调查。结果 晚期癌症患者代理决策者决策困境得分为30.00(21.50,38.50)分,决策疲劳得分为13.00(6.50,18.00)分,医师信任得分为(30.75±7.31)分,社会支持得分为(36.48±8.31)分;Pearson相关分析显示,晚期癌症患者代理决策者决策困境总分及各维度得分均与决策疲劳总分呈正相关(P<0.01),与医师信任、社会支持总分及各维度得分呈负相关(P<0.01);多元线性回归分析结果显示,代理决策者的文化程度、医学背景、决策疲劳、医师信任、社会支持是晚期癌症患者代理决策者决策困境的主要影响因素(P<0.01),可解释总变异的43.7%。结论 晚期癌症患者代理决策者决策困境总体处于中等水平,代理决策者的文化程度、医学背景、决策疲劳、医师信任和社会支持影响代理决策者决策困境。建议护理管理者采取有效措施帮助代理决策者更好地理解问题和选择方案,提高决策质量,以减轻代理决策者的决策压力和困境。 展开更多
关键词 晚期癌症 患者 护理 代理决策者 决策困境 决策疲劳 医师信任 社会支持
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中国自然土壤brGDGTs含量的变化规律及其对古环境研究的启示
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作者 王欢业 苗瑞 +4 位作者 卢红选 赵增浩 蔡泽园 盛维娟 刘卫国 《地理科学》 北大核心 2025年第8期1646-1656,共11页
由细菌产生的支链甘油二烷基甘油四醚类化合物(brGDGTs),是示踪过去气候环境变化的重要工具。然而,目前关于此类生物标志物的研究主要集中在基于其不同组分相对分布的气候代用指标,关于其总体含量的影响因素还少有研究。这限制了对于地... 由细菌产生的支链甘油二烷基甘油四醚类化合物(brGDGTs),是示踪过去气候环境变化的重要工具。然而,目前关于此类生物标志物的研究主要集中在基于其不同组分相对分布的气候代用指标,关于其总体含量的影响因素还少有研究。这限制了对于地质记录中brGDGTs含量气候指示意义以及brGDGTs指标季节性的合理解读。本研究调查了中国大范围表土中的brG-DGTs含量,并分析了其与环境因子(包括干旱指数、土壤pH和温度)的关系。结果显示,在全国范围内brGDGTs含量与干旱指数具有最强的相关性,而在不同区域brGDGTs含量均与干旱指数存在中等或较强正相关,但与pH值或温度的相关性不稳定,说明土壤湿度可能是现代表土中brGDGTs含量的主控因素。因此,地质记录中brGDGTs含量的波动可能反映了过去的干湿环境变化。另外,研究结果也表明,土壤中brGDGTs古温度代用指标的季节性,可能不仅包括通常认为的温度的季节性变化,也会受湿度(降水)的季节性变化所影响。 展开更多
关键词 土壤 brGDGTs 气温 古环境 干旱指数 指标季节性
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铁同位素及其在古海洋环境演化过程中的应用
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作者 杨曦 王义东 王中良 《地球与环境》 北大核心 2025年第1期143-152,共10页
铁是具有多价态特性的氧化还原敏感元素,其形态和同位素经常被作为环境标识,尤其是对现代和古海洋有重要的环境指示意义。本文通过总结铁在现代和古海洋环境中的同位素组成及分馏机制、评述早期含铁矿物的成因,来支持太古代早期就出现... 铁是具有多价态特性的氧化还原敏感元素,其形态和同位素经常被作为环境标识,尤其是对现代和古海洋有重要的环境指示意义。本文通过总结铁在现代和古海洋环境中的同位素组成及分馏机制、评述早期含铁矿物的成因,来支持太古代早期就出现了厌氧氧化作用的观点。厌氧氧化作用将海洋中部分溶解铁氧化,这导致了溶解态铁富集轻铁同位素并间接造成了铁建造的形成。研究古海洋含铁矿物的成因极其困难,这是由于现代环境极难还原古海洋环境的化学物理条件。同位素技术的发展实现了低含量铁的同位素测定,铁同位素及其分馏可以示踪古海洋中铁元素的行为特征并指示当时的海洋环境。因此,现代研究需要结合实验室模拟和现代类太古代环境来解决古海洋中铁同位素分馏机制,并结合其他元素的多同位素技术手段探讨古海洋中化学成分和含铁矿物的成因,这对矿产资源的探寻和生命起源的探索具有重要的意义。 展开更多
关键词 铁同位素 铁同位素分馏 铁形态 氧化还原环境标识
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青藏高原古湖沼学与古气候学研究中存在的基础科学问题初探
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作者 侯居峙 《地理科学》 北大核心 2025年第5期933-940,共8页
湖泊沉积物蕴含有丰富的气候环境变化信息,是研究末次冰消期以来气候环境变化的理想介质。本文采用青藏高原典型湖泊的古湖沼学记录,举例说明研究过程中通常被忽略的一些基础科学问题,如湖泊分类、代用指标指示意义、湖泊状态转变历史... 湖泊沉积物蕴含有丰富的气候环境变化信息,是研究末次冰消期以来气候环境变化的理想介质。本文采用青藏高原典型湖泊的古湖沼学记录,举例说明研究过程中通常被忽略的一些基础科学问题,如湖泊分类、代用指标指示意义、湖泊状态转变历史等如何影响不同代用指标记录的解释。对湖泊基础科学问题的深入理解,不仅有助于合理地解释代用指标记录,正确重建过去湖泊过程与气候环境变化,对深入理解气候环境变化过程及机制也大有裨益。 展开更多
关键词 青藏高原湖泊 古湖沼学研究 湖泊基础信息 代用指标
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一种基于区块链与代理重加密的医院财务数据加密算法
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作者 张扬 钱颖 +1 位作者 张子伊 张丽湘 《自动化技术与应用》 2025年第10期115-119,共5页
针对信息共享技术中容易发生的数据安全性问题,此次研究提出一种区块链数据共享的代理重加密算法,并将其应用于医院财务管理平台中。该模型能对数据进行动态调整。研究对所提方法进行了性能测试和医院财务数据加密仿真实验。结果显示,... 针对信息共享技术中容易发生的数据安全性问题,此次研究提出一种区块链数据共享的代理重加密算法,并将其应用于医院财务管理平台中。该模型能对数据进行动态调整。研究对所提方法进行了性能测试和医院财务数据加密仿真实验。结果显示,在数据容量为128 B的情况下,在加密和解密的过程中分别用了39.98 ms和9.77 ms;且无论数据大小为128 B还是1024 B,研究方案加密和解密的运行时间均短于对照方案。由此,研究所提方法在数据加密控制领域具有较为广泛的应用前景。 展开更多
关键词 区块链 代理重加密 医院财务 数据共享
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决策冲突在晚期癌症患者代理决策者社会支持与决策疲劳间的中介作用
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作者 李红贺 韩玉香 +2 位作者 曹雨凝 袁立杰 宋冰冰 《护理学报》 2025年第22期43-49,共7页
目的探讨决策冲突在晚期癌症患者代理决策者社会支持与决策疲劳间的中介作用。方法采用便利抽样法,于2024年3—7月选取某医科大学附属肿瘤医院接受治疗的晚期癌症患者代理决策者328名为研究对象,采用一般资料调查表、决策疲劳量表、决... 目的探讨决策冲突在晚期癌症患者代理决策者社会支持与决策疲劳间的中介作用。方法采用便利抽样法,于2024年3—7月选取某医科大学附属肿瘤医院接受治疗的晚期癌症患者代理决策者328名为研究对象,采用一般资料调查表、决策疲劳量表、决策冲突量表及社会支持评定量表进行调查。运用AMOS 26.0构建结构方程模型,并采用Bootstrap法对中介效应模型进行检验。结果本组晚期癌症患者代理决策者决策疲劳总分为(15.03±2.16)分,决策冲突总分为(28.21±4.96)分,社会支持总分为(36.51±8.81)分。本组晚期癌症患者代理决策者决策疲劳总分与决策冲突总分呈正相关(r=0.330,P<0.01),与社会支持总分呈负相关(r=-0.208,P<0.01),社会支持总分与决策冲突总分呈负相关(r=-0.677,P<0.01)。决策冲突在晚期癌症患者代理决策者社会支持与决策疲劳间起部分中介作用,中介效应占47.5%。结论决策冲突是晚期癌症患者代理决策者社会支持与决策疲劳间的中介变量。护理管理者在对晚期癌症患者代理决策者进行干预时,不仅要注重提供直接的社会支持以减轻决策疲劳,还应通过开展针对性的咨询服务调节和化解决策冲突,帮助代理决策者降低决策疲劳感。 展开更多
关键词 中介作用 决策疲劳 晚期癌症 代理决策者 社会支持 决策冲突
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“蹭吸”型代购毒品行为的类型划分与司法认定
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作者 李立丰 王一帆 《北方法学》 2025年第5期79-94,共16页
贩卖毒品是对毒品进行具有交易性质的有偿转让行为。代购毒品在具备牟利目的时,帮助性质的毒品转让行为变为交易性质的毒品转让行为,从而符合贩卖毒品罪的构成要件。“蹭吸”型代购毒品行为在构成贩卖毒品罪的认定上应采用二者定性等价... 贩卖毒品是对毒品进行具有交易性质的有偿转让行为。代购毒品在具备牟利目的时,帮助性质的毒品转让行为变为交易性质的毒品转让行为,从而符合贩卖毒品罪的构成要件。“蹭吸”型代购毒品行为在构成贩卖毒品罪的认定上应采用二者定性等价而定量不等价的规则。“蹭吸”依据不同情形可分为交易性质的“蹭吸”和赠与性质的“蹭吸”,有明确约定或多次“蹭吸”为交易性质的“蹭吸”,所“蹭吸”毒品作为代购行为的对价交换,属于代购毒品牟利,构成贩卖毒品罪。无明确约定的初次“蹭吸”,应为无偿赠与,不体现代购行为的交易性质。“蹭吸”型代购毒品行为在毒品犯罪数量认定时,应采取排除“蹭吸”部分为原则,“蹭吸”部分无法查明时则将全部转让毒品认定为贩卖数量,量刑时酌情考虑代购者的“蹭吸”情节。 展开更多
关键词 代购毒品 蹭吸 贩卖毒品 代购牟利
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网络相亲中的技术嵌入与代理机制研究
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作者 孙凤 罗振男 康慧琳 《内蒙古民族大学学报(哲学社会科学版)》 2025年第2期106-117,共12页
互联网技术的进步推动了网络相亲的发展,相亲平台作为隐形红娘,借助算法技术为求偶者推荐交往对象,使择偶范围不再受时空的限制。从网络相亲的技术嵌入和代理机制入手,通过对34名拥有网络相亲经历者的访谈发现,网络相亲通过标准化的测... 互联网技术的进步推动了网络相亲的发展,相亲平台作为隐形红娘,借助算法技术为求偶者推荐交往对象,使择偶范围不再受时空的限制。从网络相亲的技术嵌入和代理机制入手,通过对34名拥有网络相亲经历者的访谈发现,网络相亲通过标准化的测量技术、精准化的算法推荐实现技术嵌入;相亲平台作为隐秘的代理人,在提供庞大择偶资源的同时,提高了求偶者的自由度;网络相亲存在信息质量问题,加之算法无形中的引导,产生了“冲浪式”聊天偏好和“等公交车式”的择偶行为,增加了亲密关系中的风险。 展开更多
关键词 互联网相亲 技术嵌入 代理择偶
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