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Rapidly growing primordial black holes as seeds of the massive high-redshift JWST Galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 143-150页

作者： Guan-Wen Yuan Lei Lei Yuan-Zhu Wang Bo Wang Yi-Ying Wang Chao Chen Zhao-Qiang Shen Yi-fu cai Yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China Institute of High Energy Physics Chinese Academy of Sciences Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of China Jockey Club Institute for Advanced Study The Hong Kong University of Science and Technology

A group of massive galaxies at redshifts of z■7 have been recently detected by the James Webb Space Telescope（JWST）, which were unexpected to form at such an early time within the standard Big Bang cosmology. In this work, we propose that this puzzle can be explained by the presence of some primordial black holes（PBHs） with a mass of ～1000M⊙. These PBHs act as seeds for early galaxy formation with masses of ～10～8-1010M⊙at high redshift, hence accounting for the JWST observations. We use a hierarchical Bayesian inference framework to constrain the PBH mass distribution models, and find that the Lognormal model with the Mc～750M⊙is preferred over other hypotheses. These rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects, similar to those recently discovered by JWST. Although we focused on PBHs in this work, the bound on the initial mass of the seed black holes remains robust even if they were formed through astrophysical channels.

关键词： primordial black hole dark matter halo black hole accretion primordial galaxies

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Primordial black hole mass functions as a probe of cosmic origin

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 164-171页

作者： Yi-fu cai Chengfeng Tang Geyu Mo Sheng-Feng Yan Chao Chen Xiao-Han Ma Bo Wang Wentao Luo Damien A.Easson Antonino Marcianò Deep Space Exploration Laboratory/School of Physical Sciences University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Researches in Galaxies and Cosmology/Department of Astronomy School of Astronomy and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Istituto Nazionale di Fisica Nucleare(INFN) Sezione di MilanoMilano 20146Italy DiSAT Universitàdegli Studi dell'InsubriaComo 22100Italy Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina Department of Physics Arizona State UniversityTempe 85287-1504USA Department of Physics&Center for Field Theory and Particle Physics Fudan UniversityShanghai 200433China Laboratori Nazionali di Frascati INFN Via Enrico Fermi 541 Frascati(Roma)00044Italy INFN sezione Roma Tor Vergata Rome I-00133Italy School of Physics University of Electronic Science and Technology of ChinaChengdu11731China

We discuss a novel window to probe the origin of our universe via the mass functions of primordial black holes(PBHs).The mass functions of PBHs are simply estimated using the conventional Press-Schechter formalism for two paradigms of cosmic origin,including inflationaryΛCDM and bounce *** standard inflationaryΛCDM model cannot generate an appreciable number of massive PBHs;however,non-trivial inflation models with blue-tilted power spectra at small scales and matter bounce cosmology provide formation mechanisms for heavy PBHs,which in turn,may seed the observed supermassive black holes(SMBHs).By fitting the SMBH mass functions at high redshift(z~6)derived from Sloan Digital Sky Survey(SDSS)and Canada-France High-z Quasar Survey(CFHQS)quasars,for two paradigms of cosmic origin,we derive constraints on the PBH density fraction fPBHat z~6 and the characteristic mass M_(★),with the prior assumption that all SMBHs stem from *** demonstrate that this newly proposed procedure,relying on astronomical measurements that utilize deep-field surveys of SMBHs at high redshift,can be used to constrain models of cosmic ***,although not the main focus of this paper,we evolve the mass function from z~6 to z~0 through an assumption of 3×10^(8)-year Eddington’s accretion,and give a rough estimation of fPBHat z~0.

关键词： origin cosmic massive

Agricultural drought vulnerability in the middle reaches of Yangtze River Basin under environmental change

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Journal of Earth Science 2024年

作者： Peng Yang Fei Xu Jun Xia Jiang Li Libo Zhou cai fu State Key Laboratory of Hydroscience and Engineering， Tsinghua University School of Geography and Information Engineering， China University of Geosciences Information Center of Department of Natural Resources of Hubei Province School of Water Resources and Hydropower Engineering， Wuhan University Wuhan C-Geo Clouds Science and Tech Co.， Ltd

Climate change and economic development impact the population expansion and water shortage in the middle reaches of the Yangtze River Basin (MYRB)， leading directly to drought aggravation-expansion and impacting agricultural production in the MYRB. Therefore， this study quantitatively evaluated agricultural drought vulnerability in the MYRB based on the variable fuzzy evaluation model (VFEM). The main conclusions are as follows: (1) The arable land in the MYRB gradually decreased between 2005 and 2020， whereas the forest cover decreased and then increased; (2) precipitation and evapotranspiration were the key factors affecting the agricultural drought vulnerability (e.g.， weights of 0.24 and 0.21)， whereas arable land density and gross domestic product (GDP) per capita played less significant roles; and (3) the agricultural drought vulnerability in the MYRB during 2005–2020 was mainly at level 3 and below， with higher drought vulnerability in the western and northern regions， which had a higher drought risk potential.

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Nurse anesthetists’perceptions and experiences of managing emergence delirium:A qualitative study

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World Journal of Psychiatry 2024年第4期14卷 553-562页

作者： Yi Xin fu-cai Lin Chen Huang Bin He Ya-Ling Yan Shuo Wang Guang-Ming Zhang Rui Li Wuxi Medical College Jiangnan UniversityWuxi 214122Jiangsu ProvinceChina Department of Anesthesiology Tongren Hospital Shanghai Jiao Tong University School of MedicineShanghai 200335China Department of Nursing Tongren Hospital Shanghai Jiao Tong University School of MedicineShanghai 200335China

BACKGROUND This study employs a descriptive phenomenological approach to investigate the challenges anesthesia nurses face in managing emergence delirium(ED),a common and complex postoperative complication in the post-anesthesia care *** role of nurses in managing ED is critical,yet research on their understanding and management strategies for ED is *** To investigate anesthetic nurses’cognition and management experiences of ED in hopes of developing a standardized management *** This study employed a descriptive phenomenological approach from qualitative research *** sampling was utilized to select 12 anesthetic nurses from a tertiary hospital in Shanghai as research ***-structured interviews were conducted,and the data were organized and analyzed using Colaizzi’s seven-step analysis method,from which the final themes were *** After analyzing the interview content,four main themes and eight subthemes were distilled:Inefficient cognition hinders the identification of ED(conceptual ambiguity,empirical identification),managing diversity and challenges(patientcentered safe care,low level of medical-nursing collaboration),work responsibilities and pressure coexist(heavy work responsibilities,occupational risks and stress),demand for high-quality management(expecting the construction of predictive assessment tools and prevention strategies,and pursuing standardized management processes to enhance management effectiveness).CONCLUSION Nursing managers should prioritize the needs and suggestions of nurses in order to enhance their nursing capabilities and provide guidance for standardized management processes.

关键词： Anesthetic nurse Emergence delirium Postoperative complications Cognition Disease management Qualitative research

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我国公共图书馆的绩效困境与因应策略

兰州大学学报（社会科学版） 2024年第2期52卷 151-162页

作者：岳楠傅才武湖北大学新闻传播学院湖北武汉430062 武汉大学国家文化发展研究院湖北武汉430062

在构建现代公共文化服务体系的背景下,图书馆发展绩效问题成为学界和业界关注的焦点。对比近二十年的绩效变化,省、市、县级公共图书馆间的差异与财政投入政策并不匹配。对公共图书馆行业结构性矛盾的量化研究发现,在文化事业单位(与行... 详细信息

在构建现代公共文化服务体系的背景下,图书馆发展绩效问题成为学界和业界关注的焦点。对比近二十年的绩效变化,省、市、县级公共图书馆间的差异与财政投入政策并不匹配。对公共图书馆行业结构性矛盾的量化研究发现,在文化事业单位(与行业行政体系连接)向独立法人单位(与市场和社群体系连接)转轨、从传统服务方式向数字服务方式转轨“双重转型”的作用下,公共图书馆存在普遍性的“绩效困境”,以财政投入带动行业发展的传统治理模式正在逐渐失去效率。财政拨款带动省级公共图书馆发展的效果并不稳定;市级公共图书馆活力不足;县级公共图书馆对资源的需求仍旧突出。必须转变单一财政投入模式,推动财政文化管理方式改革,以公众需求和满意度为核心重建公共图书馆绩效评价激励机制,实现公共文化领域多元治理。

关键词：公共图书馆现代公共文化服务体系绩效困境结构性矛盾

Bowel preparation experiences and needs before follow-up colonoscopy in older adult postoperative colorectal cancer patients: A qualitative study

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World Journal of Gastrointestinal Surgery 2024年第9期16卷 2968-2978页

作者： Bin He Yi Xin Rui Li fu-cai Lin Guang-Ming Zhang Hai-Jing Zhu Wuxi Medical College The Jiangnan UniversityWuxi 214122Jiangsu ProvinceChina Department of Nursing The Tongren Hospital Shanghai Jiao Tong University School of MedicineShanghai 200335China Department of Anesthesiology The Tongren Hospital Shanghai Jiao Tong University School of MedicineShanghai 200335China Department of Endoscopy The Tongren Hospital Shanghai Jiao Tong University School of MedicineShanghai 200335China

BACKGROUND The bowel preparation process prior to colonoscopy determines the quality of the bowel preparation,which in turn affects the quality of the ***-scopy is an essential procedure for postoperative follow-up monitoring of colorec-tal cancer(CRC)*** studies have shown that advanced age and a history of colorectal resection are both risk factors for inadequate bowel ***,little attention has been paid to the bowel preparation experiences and needs of predominantly older adult postoperative CRC *** To explore the experiences and needs of older adult postoperative CRC patients during bowel preparation for follow-up *** Fifteen older adult postoperative CRC patients who underwent follow-up colonoscopy at a tertiary hospital in Shanghai were selected using purposive sampling from August 2023 to November *** phenomenological method in qualitative research was employed to construct an interview outline and conduct semi-structured interviews with the ***'s seven-step analysis was utilized to organize,code,categorize,summarize,and verify the interview *** The results of this study were summarized into four themes and eight sub-themes:(1)Inadequate knowledge about bowel preparation;(2)Decreased physiological comfort during bowel preparation(gastrointestinal discomfort and sleep deprivation caused by bowel cleansing agents,and hunger caused by dietary restrictions);(3)Psychological changes during different stages of bowel preparation(pre-preparation:Fear and resistance due to previous experiences;during preparation:Irritation and helplessness caused by taking bowel cleansing agents,and post-preparation:Anxiety and worry while waiting for the colonoscopy);and(4)Needs related to bowel preparation(detailed instructions from healthcare professionals;more ideal bowel cleansing agents;and shortened waiting times for colonoscopy).CONCLUSION Older adult postoperative CRC patients'kn

关键词： Older people Colorectal cancer Colonoscopy Bowel preparation Health promotion Nursing Qualitative research

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国家文化公园超级情绪价值的表征与作用机制

兰州大学学报（社会科学版） 2024年第4期52卷 106-118页

作者：皮彦芳傅才武武汉大学国家文化发展研究院湖北武汉430072

随着物质生活水平的不断提高,人们的情绪需求越来越强烈,情绪价值成为具有巨大拓展潜力的价值维度。国家文化公园作为彰显国家品质的巨型文旅体验空间和中华文化重要标识,理论上具有超越一般旅游目的地的情绪价值,可更好地给人以积极情... 详细信息

随着物质生活水平的不断提高,人们的情绪需求越来越强烈,情绪价值成为具有巨大拓展潜力的价值维度。国家文化公园作为彰显国家品质的巨型文旅体验空间和中华文化重要标识,理论上具有超越一般旅游目的地的情绪价值,可更好地给人以积极情绪和情感满足。对长江国家文化公园武汉段九个代表性景点的考察表明,国家文化公园可在情绪层面诱发敬畏情绪,进而在情感层面强化国家认同,具有长时效、广覆盖、多向度的超级情绪价值。对国家文化公园展示的壮美自然山川、丰富历史文化、先辈才华气节的认知评价,可以诱发敬畏情绪;国民文化认知和国家文化认知在向国家认同升华的过程中发挥链式中介作用。因此,在国家文化公园建设中,应加强文化旅游资源的遴选与整合,国民文化提炼展示和国家文化宣传推广,敬畏情绪和国家认同的研究、测量、评估,从而更好地实现其超级情绪价值。

关键词：国家文化公园旅游目的地情绪价值敬畏情绪国家认同

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基于区块链和简短可链接环签名的安全电子投票方案

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东北大学学报（自然科学版） 2024年第5期45卷 619-627页

作者：吴淇毓杨帆周福才冯达东北大学软件学院辽宁沈阳110169

围绕当前多数电子投票方案存在中心化、未能实现匿名投票等问题,提出基于区块链和简短可链接环签名的安全电子投票方案.通过设计一个简短可链接环签名方案,结合区块链技术,构造了一个具体、安全、高效的电子投票方案,给出了其系统模型... 详细信息

围绕当前多数电子投票方案存在中心化、未能实现匿名投票等问题,提出基于区块链和简短可链接环签名的安全电子投票方案.通过设计一个简短可链接环签名方案,结合区块链技术,构造了一个具体、安全、高效的电子投票方案,给出了其系统模型、算法形式化定义以及详细描述.与已有方案相比,该方案允许大规模人员投票,且支持多个投票选项以及自动计票等多个功能.安全分析和实验结果表明,该方案在满足匿名性、不可伪造性和隐私性等更多安全目标的同时在计算开销方面仍具有优势.

关键词：电子投票区块链简短可链接环签名安全计算去中心化

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基于LU分解的安全外包求解线性代数方程组方法

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东北大学学报（自然科学版） 2024年第4期45卷 457-463,506页

作者：冯达周福才吴淇毓李鲍东北大学软件学院辽宁沈阳110169

由于现有协议的安全性为基于某种安全假设的计算安全,依赖于敌手的计算能力,因此,本文针对恶意敌手模型,使用矩阵伪装技术对方程的系数矩阵进行隐藏,结合矩阵的LU分解(lower-upper decomposition)算法,提出一种新的信息论安全外包求解... 详细信息

由于现有协议的安全性为基于某种安全假设的计算安全,依赖于敌手的计算能力,因此,本文针对恶意敌手模型,使用矩阵伪装技术对方程的系数矩阵进行隐藏,结合矩阵的LU分解(lower-upper decomposition)算法,提出一种新的信息论安全外包求解线性代数方程组(information-theoretically secure outsourcing of linear algebraic equations,ITS-OutsLAE)方法 .与之前的研究相比,在保持计算和通信复杂度与现有最优方案保持一致的同时,首次将方程组唯一解的安全性提升至信息论安全(完美保密).给出了形式化的安全性证明,并通过理论分析和实验证明了所提方法的实用性.

关键词：线性代数方程组信息论安全安全外包 LU分解恶意敌手模型

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