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Human migration and occupation of Eurasia

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Episodes 2008年第2期31卷 207-210页

作者： robin W. dennell Dept. of Archaeology University of Sheffield Sheffield S 1 4ET U.K

The main current benefit of collaboration between Quaternary scientists and palaeoanthropologists （especially palaeolithic archaeologists） lies in providing a unique perspective on how human populations respond to longterm climate change. Eurasia has a superlative record of climatic changes over the last two million years, and an archaeological record that is regionally variable in quality, but which is drawn from a wide range of environmental and chronological contexts.

关键词：欧亚大陆人类迁徙活动第四纪地质时代

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黄土高原黄土地层古人类遗迹年代研究新进展

科学通报 2019年第25期64卷 2641-2653页

作者：朱照宇黄慰文吴翼邱世藩饶志国杨石霞侯亚梅谢久兵韩江伟付淑清欧阳婷萍周厚云彭莎莎 robin dennell 中国科学院广州地球化学研究所边缘海与大洋地质重点实验室广州510640 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 中国科学院古脊椎动物与古人类研究所北京100044 中国科学院南海海洋研究所边缘海与大洋地质重点实验室广州510301 赣南师范大学地理与环境工程学院赣州341000 湖南师范大学资源与环境科学学院长沙410081 南宁市环境监察支队南宁530021 河南省地质调查院郑州450001 广州地理研究所广州510070 华南师范大学地理科学学院广州510631 Department of Archaeology University of ExeterExeter EX1-6UK

自1920年以来,在中国黄土高原及邻近地区的黄土及河湖相地层分布区发现了大量的古人类活动遗迹地点,其中包括著名的泥河湾、水洞沟、萨拉乌苏、丁村、大荔、匼河-西侯度、庄浪、庆阳、三门峡、东秦岭地区以及蓝田地区等.在陕西蓝田的最... 详细信息

自1920年以来,在中国黄土高原及邻近地区的黄土及河湖相地层分布区发现了大量的古人类活动遗迹地点,其中包括著名的泥河湾、水洞沟、萨拉乌苏、丁村、大荔、匼河-西侯度、庄浪、庆阳、三门峡、东秦岭地区以及蓝田地区等.在陕西蓝田的最新研究进展是运用第四纪地质学与古人类学和旧石器考古学交叉学科的综合研究方法,以黄土-古土壤序列和高分辨率磁性地层年代框架为依据,发现了公王岭遗址黄土地层的强烈侵蚀和多组地层缺失,确定了直立人头盖骨与伴生的古动物化石所埋藏的地层不是前人原确定的粉砂质黄土L15中部(年代为1.15 Ma),而是位于一个大侵蚀面之下的S22~S23古土壤混合层(年代为1.63 Ma).同时,在蓝田上陈一带发现了新的出露良好的连续黄土-古土壤剖面(L5~L28),并在早更新世S15~L28层段的17层黄土或古土壤层位中发现了原地埋藏的数量不等的旧石器,其年代为1.26~2.12 Ma.研究结果使蓝田地区成为迄今所知非洲以外最古老的人类活动地区之一,这不仅在人类起源和演化方面提出了新的科学思考,并拓展了'黄土石器工业'和'黄土地质考古带'的研究方向,提出了中国黄土高原高分辨率黄土-古土壤序列与多时期古人类活动序列关联研究的新设想.

关键词：黄土-古土壤序列古人类遗迹年代学黄土高原

Learning about good nutrition with the 5-color front-of-package label"Nutri-Score":an experimental study

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Food Science and Human Wellness 2024年第3期13卷 1195-1200页

作者： robin C.Hau Klaus W.Lange University of Applied Sciences Landshut Landshut 84036Germany Faculty of Human Sciences University of RegensburgRegensburg 93040Germany

The Nutri-Score is a 5-color front-of-pack nutrition label designed to provide consumers with an easily understandable guideline to the healthiness of food *** impact that the Nutri-Score may have on consumers'choices is unclear since different experimental paradigms have found vastly different effect *** the present study,we have investigated how student participants change a hypothetical personal 1-daydietary plan after a learning phase during which they learn about the Nutri-Scores of the available food *** were instructed to compose a healthy diet plan in order that the question of whether the NutriScore would improve their ability to compose a healthy dietary plan could be investigated,independent of the question of whether they would apply this knowledge in their ordinary *** found a substantial(Cohen's d=0.86)positive impact on nutritional quality(as measured by the Nutrient Profiling System score of the Food Standards Agency)and a medium-sized(Cohen's d=0.43)reduction of energy *** content reduction was larger for participants who had initially composed plans with higher energy *** results suggest that the Nutri-Score has the potential to guide consumers to healthier food *** remains unclear,however,whether this potential will be reflected in real-life dietary choices.

关键词： Nutri-Score Front-of-package label Nudge Nutrition Health

Analyzing voting power in decentralized governance: Who controls DAOs?

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BLOCKCHAIN-RESEARCH AND APPLICATIONS 2024年第3期5卷 123-129页

作者： Fritsch, robin Muller, Marino Wattenhofer, Roger Swiss Fed Inst Technol CH-8092 Zurich Switzerland

We empirically study the state of three prominent DAO governance systems on the Ethereum blockchain: Compound, Uniswap and Ethereum name service (ENS). In particular, we examine how the voting power is distributed in these systems. Using a comprehensive dataset of all governance token holders, delegates, proposals, and votes, we analyze who holds the voting power and how this power is being used to influence governance decisions. While we reveal that the majority of voting power is concentrated in the hands of a small number of addresses, we rarely observe these powerful entities overturning a vote by choosing a different outcome than that of the overall community and less influential voters.

关键词： Decentralized autonomous organization DAO governance Liquid democracy Blockchain

On the inviscid limit of the compressible Navier-Stokes equations near Onsager's regularity in bounded domains

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Science China Mathematics 2024年第1期67卷 1-22页

作者： robin Ming Chen Zhilei Liang Dehua Wang Runzhang Xu Department of Mathematics University of PittsburghPittsburghPA 15260USA School of Mathematics Southwestern University of Finance and EconomicsChengdu 611130China College of Mathematical Sciences Harbin Engineering UniversityHarbin 150001China

The viscous dissipation limit of weak solutions is considered for the Navier-Stokes equations of compressible isentropic flows confined in a bounded *** establish a Kato-type criterion for the validity of the inviscid limit for the weak solutions of the Navier-Stokes equations in a function space with the regularity index close to Onsager’s critical *** particular,we prove that under such a regularity assumption,if the viscous energy dissipation rate vanishes in a boundary layer of thickness in the order of the viscosity,then the weak solutions of the Navier-Stokes equations converge to a weak admissible solution of the Euler *** approach is based on the commutator estimates and a subtle foliation technique near the boundary of the domain.

关键词： inviscid limit Navier-Stokes equations Euler equations weak solutions bounded domain Katotype criterion Onsager’s regularity

Chiral boryl radical catalyzed asymmetric radical cycloisomerization

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Science China Chemistry 2024年第7期67卷 2121-2123页

作者： Jiamiao Jin Shi-Chao Ren Yonggui robin Chi National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore

Asymmetric catalytic organic synthesis is of profound importance in modern research and industries,providing optically enriched molecules with diverse structures and functions[1].Enzymes,transition metal complexes,and simple organic molecules have all been found as powerful catalysts that enable the bond breaking and forming events with excellent control over stereo-selectivity *** the realm of designed small molecule organic catalysts.

关键词： radical catalyzed asymmetric

New approach for particle size and shape analysis of iron-based oxygen carriers at multiple oxidation states

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Particuology 2024年第7期90卷 493-503页

作者： Victor Purnomo Marcelo Dal Belo Takehara robin Faust Lidiya Abdisa Ejjeta Henrik Leion Division of Energy and Materials Department of Chemistry and Chemical EngineeringChalmers University of TechnologyGöteborg 41258Sweden Division of Energy Science Department of Engineering Sciences and MathematicsLuleåUniversity of TechnologyLuleå97187Sweden

One of the crucial issues in the chemical looping technology lies in its bed material:the oxygen *** size analysis of an oxygen carrier is important since in a fluidized bed the material can only work well within a specific size *** the favorable size ranges for oxygen carrier materials have already been reported,none of the published studies has analyzed the particle size and shape of oxygen carriers in ***,the effect of oxygen carriers'oxidation degree on such properties has not been considered *** study aimed to report the particle size and shape analysis of five iron-based oxygen carriers,one natural ore,one synthetic material,and three residue products,at different oxidation degrees using dynamic image analysis(DIA).The oxygen carriers were prepared at different mass conversion degrees in a fluidized bed batch *** size distribution,sphericity,and aspect ratio of the oxygen carrier particles were examined experimentally using a Camsizer *** results show that the DIA method was successfully able to analyze the particle size and shape of our oxygen carriers with satisfying accuracy for *** oxidation state of the investigated materials seems to only affect the particle size and shape of oxygen carriers to a minor ***,exposures to redox cycles in a fluidized bed reactor may alter the particle size and shape of most oxygen carriers.

关键词： Oxygen carrier Size and shape analysis Dynamic image analysis Oxidation state Fluidized bed Chemical looping

Automation and Orchestration of Zero Trust Architecture:Potential Solutions and Challenges

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Machine Intelligence Research 2024年第2期21卷 294-317页

作者： Yang Cao Shiva Raj Pokhrel Ye Zhu robin Doss Gang Li Centre for Cyber Resilience and Trust Deakin UniversityBurwood 3125Australia School of Information Technology Deakin UniversityGeelong 3216Australia

Zero trust architecture(ZTA)is a paradigm shift in how we protect data,stay connected and access *** is non-perimeter-based defence,which has been emerging as a promising revolution in the cyber security *** can be used to continuously maintain security by safeguarding against attacks both from inside and outside of the network ***,ZTA automation and orchestration,towards seamless deployment on real-world networks,has been limited to be reviewed in the existing *** this paper,we first identify the bottlenecks,discuss the background of ZTA and compare it with traditional perimeter-based security *** importantly,we provide an in-depth analysis of state-of-the-art AI techniques that have the potential in the automation and orchestration of ***,in this review paper,we develop a foundational view on the challenges and potential enablers for the automation and orchestration of ZTA.

关键词： Zero trust architecture cyber security artificial intelligence access control authentication

Access to Axially Chiral Aryl Aldehydes via Carbene-Catalyzed Nitrile Formation and Desymmetrization Reaction

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Research 2024年第3期2024卷 715-721页

作者： Yuanlin Cai Ya Lv Liangzhen Shu Zhichao Jin Yonggui robin Chi Tingting Li National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore.

An approach utilizing N-heterocyclic carbene for nitrile formation and desymmetrization reaction is developed. The process involves kinetic resolution, with the axially chiral aryl monoaldehydes obtained in moderate yields with excellent optical purities. These axially chiral aryl monoaldehydes can be conveniently transformed into functionalized molecules, showing great potential as catalysts in organic chemistry.

关键词： chemistry. aldehydes chiral