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室内设计与装修 2024年第9期 24-31页

作者： [墨西哥]Estudio Carroll 麦子(编译) Cesar Belio(摄影) victor Morales(摄影) Richard Stow(摄影) Estudio Carroll

作为设计师和建筑师,在全球气温逐年上升的时代,通过项目节能减排,为地球做出贡献,变得越发重要。当有机会为一对渴望在墨西哥瓦哈卡海边拥有一片自己天地的夫妇建造一处住宅时,这种责任转变成了该项目设计理念的精神指引。

关键词：全球气温节能减排住宅设计理念建筑师墨西哥设计师

Conformity Assessment of Lead Aprons Used in Conventional Radiology: A Multi-Centre Survey in Togo

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Open Journal of Radiology 2024年第2期14卷 55-63页

作者： Massaga Dagbé Bidamin N’timon Ousmane Aminata Bah Pihou Gbandé Komi Awobanou Koku Adambounou Masamaesso Tchaou Abdoulatif Amadou Lantam Sonhaye Lama Kegdigoma Agoda-koussema Komlanvi victor Adjénou Radiology Department Kara University Hospital Kara Togo Armed Forces Reference Imaging Center (CIRA) Conakry Guinea Radiology Department Sokod Regional Hospital Sokod Togo Radiology Department Lom University Hospital Lom Togo Radiation Protection/Telemedicine Department Lom University Hospital Lom Togo Radiology Department Kara Regional Hospital Kara Togo

Aim: Lead aprons are used to protect against scattered radiation from the patient during interventional procedures and certain special conventional radiological examinations. Given the importance of the role lead aprons are supposed to play in radiation protection, we propose to assess their conformity in medical imaging departments in public and religious hospitals in Togo. Materials and method: A multi-centre survey conducted from 26 November to 06 December 2021 in the radiology departments of public and religious health facilities in Togo. All aprons in use were included. The evaluation criteria were physical (visual), quantitative (radiographic) and qualitative (dosimetric). Results: We had registred 43 aprons among wich 27 (62.79%) leaded aprons were labelled non-compliant and 16 (37.21%) were labelled compliant. Of the aprons judged to be non-compliant, 70.37% were more than 10 years old and 96.30% showed defects on the radiographic images. The most common defects were vampire marks (18.64%), multiple folds (16.96%), cracks (16.96%), multiple cracks (15.25%), tears (8.47%), absence of lead (5.08%), holes (3.39%) and lead corrosion (1.69%). Defective aprons (62.96%) had at least two defects. The defects were of thoraco-abdomino-pelvic (74.07%), thoracic (14.82%) and abdomino-pelvic (11.11%) topography. For indirect exposure at 50 and 70 kilovolts, all the aprons had an attenuation factor greater than 90%. After dosimetric measurement, 13.95% of aprons had attenuation factors below 90% for indirect exposure at 100 kilovolts. Conclusion: The compliance of the leaded decks is trifactorial (physical, radiographic and dosimetric). However, there is no significant difference in X-ray attenuation capacity between defective and normal decks.

关键词： Lead Apron Compliance Radiation Protection Radiology Togo

Transnational Dialogues on Interdisciplinary Approaches for Advancing People-Centered Warning Systems

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International Journal of Disaster Risk Science 2023年第5期14卷 868-872页

作者： victor Marchezini Cemaden–National Early Warning and Monitoring Centre of Natural Disasters São Josédos Campos12.247-016Brazil Natural Hazards Center Institute of Behavioral ScienceUniversity of Colorado BoulderBoulderCO80309USA

The United Nations Office for Disaster Risk Reduction and the World Meteorological Organization launched in 2022 the executive plan of the world program "Early Warning Systems for All" to be implemented from 2023 to *** program champions an investment of USD 3.1 billion into the four pillars of warning systems and calls for multi-hazard and peoplecentered warning systems(PCWS).However,there is a scientific gap concerning interdisciplinary approaches to promoting *** by the call for action of "Early Warning Systems for All" and warning research gaps on the lack of interdisciplinarity,a workshop series "Interdisciplinary Approaches for Advancing People-Centered Warning Systems" was held in early *** short article shares the preliminary findings and recommendations of this research,which involved a transnational virtual dialogue between one scientific organization in Brazil and one from the United *** findings and recommendations discussed in three virtual sessions and one collective working paper were centered on three aspects:promoting interdisciplinary integration in research;the need to discuss the characteristics of a PCWS;and promoting problem-and solution-based programs with people to integrate them at all phases of the warning system.

关键词： Capacity building Cooperation Interdisciplinary methods Warning implementation Warning research

基于深度强化学习的空天地一体化网络信息物理系统垂直切换策略

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通信学报 2024年第8期45卷 180-191页

作者：武艳潘广川姚明旿杨清海梁中明西安电子科技大学空天地一体化综合业务网全国重点实验室陕西西安710071 深圳大学计算机与软件学院物联网研究中心广东深圳518060

针对空天地一体化网络信息物理系统模型复杂、很难获得网络拓扑先验知识和模型化假设的特点,研究其基于深度强化学习的垂直切换策略。首先,综合考虑系统稳定性、切换开销和网络使用成本约束,将垂直切换策略问题建模为约束马尔可夫决策过... 详细信息

针对空天地一体化网络信息物理系统模型复杂、很难获得网络拓扑先验知识和模型化假设的特点,研究其基于深度强化学习的垂直切换策略。首先,综合考虑系统稳定性、切换开销和网络使用成本约束,将垂直切换策略问题建模为约束马尔可夫决策过程(CMDP),并给出保证可行解存在的充分条件;其次,提出约束-近端策略优化(CPPO)算法解决该问题,并在基站侧引入分布式强化学习机制加速训练收敛。相较于基准策略,仿真验证了所提垂直切换策略的优越性和有效性。

关键词：空天地一体化网络信息物理系统深度强化学习垂直切换

Multi-temperature modeling of femtosecond laser pulse on metallic nanoparticles accounting for the temperature dependences of the parameters

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Nanotechnology and Precision Engineering 2022年第4期5卷 26-45页

作者： victor K.Pustovalov Belarussian National Technical University Pr.Independency65Minsk 220013Belarus

This review considers the fundamental dynamical processes of metal nanoparticles during and after the impact of a femtosecond laser pulse on a nanoparticle,including the absorption of *** the sequence of events after photon absorption and their timescales is important for many applications of *** processes are discussed,starting with optical absorption by electrons,proceeding through the relaxation of the electrons due to electron–electron scattering and electron–phonon coupling,and ending with the dissipation of the nanoparticle energy into the *** goal is to consider the timescales,values,and temperature dependences of the electron heat capacity and the electron–phonon coupling parameter that describe these processes and how these dependences affect the electron energy ***-and four-temperature models for describing electron–phonon relaxation are *** emphasis is paid to the proposed analytical approach to modeling processes during the action of a femtosecond laser pulse on a metal *** consider the temperature dependences of the electron heat capacity and the electron–phonon coupling factor of the *** entire process is divided into four stages:(1)the heating of the electron system by a pulse,(2)electron thermalization,(3)electron–phonon energy exchange and the equalization of the temperature of the electrons with the lattice,and(4)cooling of the *** is an appropriate analytical description of each *** four-temperature model can estimate the parameters of the laser and nanoparticles needed for applications of femtosecond laser pulses and nanoparticles.

关键词： Femtosecond pulse Nanoparticle Metallic Model Thermal processes Analytical solution

ESTIMATION AND UNCERTAINTY QUANTIFICATION FOR PIECEWISE SMOOTH SIGNAL RECOVERY

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Journal of Computational Mathematics 2023年第2期41卷 246-262页

作者： victor Churchill Anne Gelb Department of Mathematics The Ohio State UniversityColumbusOHUSA Department of Mathematics Dartmouth CollegeHanoverNHUSA

This paper presents an application of the sparse Bayesian learning(SBL)algorithm to linear inverse problems with a high order total variation(HOTV)sparsity *** the problem of sparse signal recovery,SBL often produces more accurate estimates than maximum a posteriori estimates,including those that useℓ1 ***,rather than a single signal estimate,SBL yields a full posterior density estimate which can be used for uncertainty ***,SBL is only immediately applicable to problems having a direct sparsity prior,or to those that can be formed via *** paper demonstrates how a problem with an HOTV sparsity prior can be formulated via synthesis,and then utilizes *** expands the class of problems available to Bayesian learning to include,e.g.,inverse problems dealing with the recovery of piecewise smooth functions or signals from *** examples are provided to demonstrate how this new technique is effectively employed.

关键词： High order total variation regularization Sparse Bayesian learning Analysis and synthesis Piecewise smooth function recovery

Commitment of human mesenchymal stromal cells to skeletal lineages is independent of their morphogenetic capacity

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World Journal of Stem Cells 2023年第7期15卷 701-712页

作者： Jessica Cristina Marín-Llera Damián García-García Estefania Garay-Pacheco victor adrian Cortes-Morales Juan Jose Montesinos-Montesinos Jesus Chimal-Monroy Medicina Genómica y Toxicología Ambiental Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de MéxicoCoyoacan 04510Mexico Laboratorio de Células Troncales Mesenquimales Unidad de Investigación Médica en Enfermedades OncológicasHospital de Oncología Centro Medico Nacional Siglo XXIInstituto Mexicano del Seguro SocialMexico City 06720Mexico Departamento de Medicina Genómica y Toxicología Ambiental Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de MéxicoCoyoacan 04510Mexico

BACKGROUND Mesenchymal stromal cells(MSCs)are multipotent cell populations obtained from fetal and adult *** share some characteristics with limb bud mesodermal cells such as differentiation potential into osteogenic,chondrogenic,and tenogenic lineages and an embryonic mesodermal *** MSCs differentiate into skeletal-related lineages in vitro,they have not been shown to selforganize into complex skeletal structures or connective tissues,as in the *** this work,we demonstrate that the expression of molecular markers to commit MSCs to skeletal lineages is not sufficient to generate skeletal elements in *** To evaluate the potential of MSCs to differentiate into skeletal lineages and generate complex skeletal structures using the recombinant limb(RL)*** We used the experimental system of RLs from dissociated-reaggregated human placenta(PL)and umbilical cord blood(UCB)*** being harvested and reaggregated in a pellet,cultured cells were introduced into an ectodermal cover obtained from an early chicken limb ***,this filled ectoderm was grafted into the back of a donor chick *** these conditions,the cells received and responded to the ectoderm’s embryonic signals in a spatiotemporal manner to differentiate and pattern into skeletal *** response to differentiation and morphogenetic signals was evaluated by quantitative poly-merase chain reaction,histology,immunofluorescence,scanning electron microscopy,and in situ *** We found that human PL-MSCs and UCB-MSCs constituting the RLs expressed chondrogenic,osteogenic,and tenogenic molecular markers while differentially committing into limb lineages but could not generate complex structures in ***-RL from PL or UCB were committed early to chondrogenic ***,the UCB-RL osteogenic commitment was favored,although preferentially to a tenogenic cell *** findings suggest that the commitment of MSCs to differentiate int

关键词： Human mesenchymal stromal cells Recombinant limbs Mesenchymal stromal cell morphogene-sis Mesenchymal stromal cell in vivo differentiation Skeletal tissues

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共产国际柏林西欧书记处活动研究

当代世界社会主义问题 2024年第2期 42-52,165页

作者：曹漩 [德]维克多·杰宁豪斯北京师范大学历史学院北京100875 国汉堡大学东北欧德意志历史与文化研究所德国吕讷堡21335

俄国十月革命后,俄共(布)将德国作为欧洲革命的桥头堡,在柏林设立西欧书记处,由共产国际著名活动家雅科夫·赖希领导。书记处肩负为欧洲乃至世界革命提供现实保障的使命,在德国进行了一系列机密性活动,包括在西欧建立共产国际网络,向欧... 详细信息

俄国十月革命后,俄共(布)将德国作为欧洲革命的桥头堡,在柏林设立西欧书记处,由共产国际著名活动家雅科夫·赖希领导。书记处肩负为欧洲乃至世界革命提供现实保障的使命,在德国进行了一系列机密性活动,包括在西欧建立共产国际网络,向欧洲左翼政党提供宣传材料和政治咨询等。其中,书记处最重要的作用是用苏俄外汇资助西方的共产党和左翼人士,充当共产国际在德国乃至整个西欧的地下经费中转站的角色。这些活动是共产国际初期实践的重要组成部分,为苏俄打破外国封锁和传播共产主义理论提供了巨大帮助。但值得注意的是,书记处在组织管理方面较为松散灵活,体现出共产国际过渡时期的特点。这主要是由欧洲局势以及共产国际的策略所决定的,并不能完全归咎到经验不足上来。书记处直接推动了共产国际对自身组织及工作方式进行变革,体现出苏联以及共产国际身份的转变:如果在20世纪初,世界革命的成败被认为是保卫新生政权的先决条件,那么到了20世纪20年代中后期,情况则有所变化,苏联成了未来世界革命的保障。

关键词：柏林西欧书记处雅科夫·赖希共产国际世界革命

Opportunities and challenges in CO_(2) utilization

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Journal of Environmental Sciences 2022年第3期34卷 322-344页

作者： Sriram Valluri victor Claremboux Surendra Kawatra Department of Chemical Engineering Michigan Technological UniversityHoughtonMI 49931USA

CO_(2) utilizations are essential to curbing the greenhouse gas effect and managing the environmental pollutant in an energy-efficient and economically-sound *** paper seeks to critically analyze these technologies in the context of each other and highlight the most important utilization avenues available thus *** review will introduce and analyze each major pathway,and discuss the overall applicability,potential extent,and major limitations of each of these pathways to utilizing CO_(2).This will include the analysis of some previously underreported utilization avenues,including CO_(2) utilization in industrial filtration and the processing of raw industrial materials such as iron and *** core theme of this paper is to seek to treat CO_(2) as a commodity instead of a liability.

关键词： CO_(2)utilization Clean energy Supercritical CO_(2) Electrochemical reduction

The Oceanus Borealis of ancient Mars

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National Science Review 2023年第9期10卷 234-235页

作者： victor R.Baker Departments of Hydrology and Atmospheric Sciences Planetary Sciences and Geosciences University of Arizona

Fifty years ago,the Mariner 9 spacecraft revealed that the Martian surface has a great planetary dichotomy separating heavily cratered southern highlands from a huge area of more lightly cratered northern *** this discovery,informal hypothesizing by geologists considered the possibility of an Earth-like water body occupying the northern lowland Martian plains.

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