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Nuclear Science and Techniques 1999年第3期10卷 143-148页

作者： WU Lijun Tom K. HEI Gerhard RANDER-PEHRSON WANG Shaohu YU Zengliang (1Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230051, China 2Center for Radiological Research, columbia university, New York 10032, USA) 中科院等离子体物理所安徽合肥 230031 columbia Univeristy 美国中科院等离子体物理所安徽合肥

columbia university microbeam was constructed in 1993 and finished by the end of 1995. It is well established and used routinely to irradiate cells in a highly localized spatial region with a defined number of α-particles. By using this probe, it is possible to study a number of radiobiological questions in ways that cannot be simulated by using conventional broad-field exposures. This report describes the development and current capabilities of the columbia university microbeam, as well as the preliminary researches undertaken.

关键词：放射生物学微射束靶细胞实验系统

Steve Coutinho, An Introduction to Daoist Philosophies. New York, NY：columbia university Press, 2013, 248pp., ISBN： 9780231143394.

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Frontiers of Philosophy in China 2017年第1期12卷 188-190页

作者： Ronnie Littlejohn Belmont university

Steve Coutinho has provided us with a new introduction to Daoism. The scope of ＂Daoist Philosophies＂ covered by this introduction is the Laozi, the Zhuangzi, and the Liezi. The author makes no use of the materials of the Daoist canon, considering them to be ＂folk beliefs, rituals, spiritual practices, and sacred texts...a pluralistic amalgamation of rival sects and teachings that have developed in lineages over the centuries...＂（7）. The overriding approach taken in this work is to relate Daoist thought to contemporary philosophical issues, and the author does not hesitate to make use of Western ideas and categories to structure his interpretations. The goal of this introduction is to show how Daoism can be embraced as a living philosophy, rather than to offer the history of the tradition.

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Rothschild, Norman H. Emperor Wu Zhao and Her Pantheon of Devis, Divinities and Dynastic Mothers. New York： columbia university Press, 2015.

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Frontiers of History in China 2016年第2期11卷 331-335页

作者： Yifeng Xie Fudan university

Wu Zhao 武曌（624-705; r. 690-705）, better known as Wu Zetian 武则天, or Empress Wu 武后, was the first and only female emperor in Chinese history. Her history and legends have attracted considerable scholarship that explores her life from various perspectives. In these studies, two significant approaches are： analysis of the relation between Wu Zetian and contemporary religious culture, and gender studies. Norman Rothschild＇s book, Emperor Wu Zhao and Her Pantheon of Devis, Divinities and Dynastic Mothers, seems to be the first monograph to combine and integrate these two approaches systematically into one framework--the concept of female divinities and their relationships with Wu Zhao all through her lengthy political life. The book will considerably expand our horizons on this topic.

关键词：哥伦比亚大学母亲出版社纽约中国历史武则天宗教文化奖学金

A thermodynamic perspective on electrode poisoning in solid oxide fuel cells

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1449-1455页

作者： Kevin Huang Department of Mechanical Engineering University of South CarolinaColumbiaUSA

A critical challenge to the commercialization of clean and high-efficiency solid oxide fuel cell(SOFC)technology is the insuf-ficient stack lifespan caused by a variety of degradation mechanisms,which are associated with cell components and chemical *** components related degradation refers to thermal/chemical/electrochemical deterioration of cell materials under operating conditions,whereas the latter regards impurities in feedstocks of oxidant(air)and reductant(fuel).This article provides a thermodynamic perspective on the understanding of the impurities-induced degradation mechanisms in *** discussion focuses on using thermodynamic ana-lysis to elucidate poisoning mechanisms in cathodes by impurity species such as Cr,CO_(2),H_(2)O,and SO_(2) and in the anode by species such as S(or H_(2)S),SiO_(2),and P_(2)(or PH_(3)).The author hopes the presented fundamental insights can provide a theoretical foundation for search-ing for better technical solutions to address the critical degradation challenges.

关键词： impurities air fuel reaction activity

Flow structure and shear stress in the presence of both ice cover on water surface and leafless vegetation in channel bed

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Journal of Hydrodynamics 2024年第2期36卷 340-354页

作者： Mahboubeh Barahimi Jueyi Sui School of Engineering University of Northern British ColumbiaPrince GeorgeCanada

This study aimed to investigate the previously unexplored effects of ice cover and submerged vegetation on flow *** were undertaken under both open channel and ice-covered flow *** bed material consisted of three non-uniform *** findings revealed that when vegetation patches were present on the bed and an ice cover was present,the velocity profiles exhibited a distinctive pattern with two peak *** kinetic energy(TKE)also exhibited two peaks,one above the vegetation bending height and another at the sheath section,with a decreasing trend towards the ice ***,quadrant analysis showed that when the flow surface is covered by an ice cover,the contributions of inward and outward events increased compared with those observed in an open channel *** most cases,these contributions surpassed the sweep and ejection *** findings enhance our understanding of vegetation’s response to diverse surface conditions and have practical implications for river management and environmental engineering.

关键词： Ice cover vegetation flow structure Reynolds shear stress turbulent kinetic energy(TKE) quadrant analysis

Polymeric piezoelectric accelerometers with high sensitivity,broad bandwidth,and low noise density for organic electronics and wearable microsystems

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Microsystems & Nanoengineering 2024年第3期10卷 63-74页

作者： Chang Ge Edmond Cretu The Department of Electrical and Computer Engineering The University of British ColumbiaVancouverBCCanada

Piezoelectric accelerometers excel in vibration *** the emerging trend of fully organic electronic microsystems,polymeric piezoelectric accelerometers can be used as vital front-end components to capture dynamic signals,such as vocal vibrations in wearable speaking assistants for those with speaking ***,high-performance polymeric piezoelectric accelerometers suitable for such applications are *** organic compounds such as PVDF have inferior properties to their inorganic counterparts such as ***,most existing polymeric piezoelectric accelerometers have very unbalanced performance *** often sacrifice resonance frequency and bandwidth for a flat-band sensitivity comparable to those of PZT-based accelerometers,leading to increased noise density and limited application *** this study,a new polymeric piezoelectric accelerometer design to overcome the material limitations of PVDF is *** new design aims to simultaneously achieve high sensitivity,broad bandwidth,and low *** samples were manufactured and characterized,demonstrating an average sensitivity of 29.45 pC/g within a±10 g input range,a 5%flat band of 160 Hz,and an in-band noise density of 1.4μg/√*** results surpass those of many PZT-based piezoelectric accelerometers,showing the feasibility of achieving comprehensively high performance in polymeric piezoelectric accelerometers to increase their potential in novel applications such as organic microsystems.

关键词： piezoelectric polymeric overcome

Influence of indoor airflow on airborne disease transmission in a classroom

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Building Simulation 2024年第3期17卷 355-370页

作者： Mojtaba Zabihi Ri Li Joshua Brinkerhoff School of Engineering Faculty of Applied ScienceUniversity of British ColumbiaKelownaCanada

It has been widely accepted that the most effective way to mitigate airborne disease transmission in an indoor space is to increase the ventilation airflow,measured in air change per hour(ACH).However,increasing ACH did not effectively prevent the spread of *** better understand the role of ACH and airflow large-scale patterns,a comprehensive fully transient computational fluid dynamics(CFD)simulation of two-phase flows based on a discrete phase model(DPM)was performed in a university classroom setting with people *** investigations encompass various particle sizes,ventilation layouts,and flow *** findings demonstrated that the particle size threshold at which particles are deemed airborne is highly influenced by the background flow strength and large-scale flow pattern,ranging from 5µm to 10µm in the cases *** effects of occupants are significant and must be precisely accounted for in respiratory particle transport *** enhanced ventilation design(UFAD-CDR)for university classrooms is introduced that places a premium on mitigating airborne disease *** to the baseline design at the same ACH,this design successfully reduced the maximum number density of respiratory particles by up to 85%.A novel airflow-related parameter,Horizontality,is introduced to quantify and connect the large-scale airflow pattern with indoor aerosol *** underscores that ACH alone cannot ensure or regulate air *** addition to the necessary ACH for air exchange,minimizing horizontal bulk motion is essential for reducing aerosol transmissibility within the room.

关键词： aerosol transmission airflow pattern horizontality COVID-19 simulation classroom ventilation

Advances and opportunities in wind energy harvesting using plasma actuators:a review

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Clean Energy 2024年第1期8卷 197-225页

作者： Javad Omidi Department of Chemical Engineering Columbia UniversityNew YorkNYUSA

The dielectric barrier discharge plasma actuator has been recognized as a leading technology for controlling fluid flow and has found remarkable applications in wind energy harvesting over the past *** turbine aerodynamics are critical in this concept and performance is mainly determined by flow controllers,although significant technical progress is still *** paper examines all the critical studies to investigate the potential application of plasma actuators for airflow control over wind *** approach has been divided into three categories:wind turbine airfoils,horizontal-axis wind turbines and vertical-axis wind turbines aerodynamic performance and generated ***,the potential functions of plasma actuators in current and future wind turbine generators are *** actuators offer promising solutions to increasing power output,minimizing torque fluctuations and enabling self-starting capabilities,particularly in vertical-axis wind *** adjusting blade pitch angles in conjunction with plasma actuators,significant improvements in airflow optimization and power extraction have been *** the advancements,challenges persist,such as determining optimal actuator placement and overcoming structural limitations,especially concerning 3D effects and high Reynolds *** plasma actuators enhance aerodynamic efficiency,their complexity needs to be balanced against marginal gains in power production,especially in high-megawatt turbines,for which controlling flow at low wind speeds is *** research must focus on the sustainable integration of plasma actuators,pitch angle adjustments and active control mechanisms to fully exploit the potential of wind energy for a sustainable future.

关键词： plasma actuator wind turbine aerodynamic performance generated power

Long-term monitoring of cycles in Clethrionomys rutilus in the Yukon boreal forest

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Integrative Zoology 2024年第1期19卷 27-36页

作者： Charles J.KREBS Alice J.KENNEY B.Scott GILBERT Rudy BOONSTRA Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada Renewable Resources Management Program Yukon UniversityWhitehorseYukonCanada Department of Biological Sciences University of Toronto ScarboroughTorontoOntarioCanada

Baseline studies of small rodent populations in undisturbed ecosystems are *** report here 50 years of mon-itoring and experimentation in Yukon of a dominant rodent species in the North American boreal forest,the red-backed vole Clethrionomys *** voles breed in summer,weigh 20–25 g,and reach a maximum density of 20 to 25 per *** populations have shown consistent 3–4-year cycles for the last 50 years with the only change being that peak densities averaged 8/ha until 2000 and 18/ha since that *** the last 25 years,we have measured food resources,predator numbers,and winter weather,and for 1-year social interactions,to estimate their contribution to changes in the rate of summer increase and the rate of overwinter *** these potential limiting factors could contribute to changes in density,and we measured their relative contributions statistically with multiple *** rate of winter decline in density was related to both food supply and winter *** rate of summer increase was related to summer berry crops and white spruce cone *** measure of predator numbers was related to winter or summer changes in vole *** was a large signal of climate change effects in these *** is no density dependence in summer population growth and only a weak one in winter population *** of our results provide a clear understanding of what generates 3–4-year cycles in these voles,and the major missing piece may be an understanding of social interactions at high density.

关键词： boreal forest climate change density dependence population cycles predation winter severity

Small molecule conjugates with selective estrogen receptor β agonism promote anti-aging benefits in metabolism and skin recovery

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2137-2152页

作者： Tarik Zahr Vijay K.Boda Jian Ge Lexiang Yu Zhongzhi Wu Jianwen Que Wei Li Li Qiang Naomi Berrie Diabetes Center Columbia UniversityNew YorkNY 10032USA Department of Molecular Pharmacology and Therapeutics Columbia UniversityNew YorkNY 10032USA Department of Pharmaceutical Sciences College of PharmacyUniversity of Tennessee Health Science CenterMemphisTN 38163USA Drug Discovery Center College of PharmacyUniversity of Tennessee Health Science CenterMemphisTN 38163USA Division of Digestive and Liver Diseases Columbia UniversityNew YorkNY 10032USA Center for Human Development Columbia UniversityNew YorkNY 10027USA Department of Pathology and Cell Biology Columbia UniversityNew YorkNY 10032USA Department of Medicine Columbia UniversityNew YorkNY 10032USA

Estrogen is imperative to mammalian reproductivity,metabolism,and ***,the hormone activating estrogen receptor(ERs)αcan cause major safety concerns due to the enrichment of ERαin female tissues and certain *** contrast,ERβis more broadly expressed in metabolic tissues and the ***,it is desirable to generate selective ERβagonist conjugates for maximizing the therapeutic effects of ERs while minimizing the risks of ERα***,we report the design and production of small molecule conjugates containing selective non-steroid ERβagonists Gtx878 or *** of aged mice with our synthesized conjugates improved aging-associated declines in insulin sensitivity,visceral adipose integrity,skeletal muscle function,and skin health,with validation in *** further uncovered the benefits of ERβconjugates in the skin using two inducible skin injury mouse models,showing increased skin basal cell proliferation,epidermal thickness,and wound ***,our ERβ-selective agonist conjugates offer novel therapeutic potential to improve aging-associated conditions and aid in rejuvenating skin health.

关键词： Estrogen receptorβ Aging Metabolism Skin injury Muscle metabolism Small molecule conjugates Regeneration Adiposity