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Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.T.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

The Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

Aerosol jet printing of surface acoustic wave microfluidic devices

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Microsystems & Nanoengineering 2024年第1期10卷 231-242页

作者： Joseph Rich Brian Cole Teng Li Brandon Lu Hanyu Fu Brittany N.Smith Jianping Xia Shujie Yang Ruoyu Zhong James L.Doherty Kanji Kaneko Hiroaki Suzuki Zhenhua Tian Aaron D.Franklin Tony Jun Huang Department of Biomedical Engineering Duke UniversityDurhamNC 27708USA Department of Electrical and Computer Engineering Duke UniversityDurhamNC 27708USA Department of Mechanical Engineering Virginia Polytechnic Institute and State UniversityBlacksburgVA 24061USA Thomas Lord Department of Mechanical Engineering and Materials Science Duke UniversityDurhamNC 27708USA Deptartment of Precision Mechanics Faculty of Science and EngineeringChuo UniversityTokyo 112-8551Japan Department of Chemistry Duke UniversityDurhamNC 27708USA

The addition of surface acoustic wave(SAW)technologies to microfluidics has greatly advanced lab-on-a-chip applications due to their unique and powerful attributes,including high-precision manipulation,versatility,integrability,biocompatibility,contactless nature,and rapid ***,the development of SAW microfluidic devices is limited by complex and time-consuming micro/nanofabrication techniques and access to cleanroom facilities for multistep photolithography and vacuum-based *** simplify the fabrication of SAW microfluidic devices with customizable dimensions and functions,we utilized the additive manufacturing technique of aerosol jet *** successfully fabricated customized SAW microfluidic devices of varying materials,including silver nanowires,graphene,and poly(3,4-ethylenedioxythiophene)polystyrene sulfonate(PEDOT:PSS).To characterize and compare the acoustic actuation performance of these aerosol jet printed SAW microfluidic devices with their cleanroom-fabricated counterparts,the wave displacements and resonant frequencies of the different fabricated devices were directly measured through scanning laser Doppler ***,to exhibit the capability of the aerosol jet printed devices for lab-on-a-chip applications,we successfully conducted acoustic streaming and particle concentration ***,we demonstrated a novel solution-based,direct-write,single-step,cleanroom-free additive manufacturing technique to rapidly develop SAW microfluidic devices that shows viability for applications in the fields of biology,chemistry,engineering,and medicine.

关键词： printing wave fluid

The neurovascular unit-on-a-chip:modeling ischemic stroke to stem cell therapy

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Neural Regeneration Research 2024年第7期19卷 1431-1432页

作者： Seonghun Kim Minjun Kim Gerald A.Grant Wonjae Lee Department of Neurosurgery Duke University School of MedicineDurhamNCUSA Department of Neurobiology Duke University School of MedicineDurhamNCUSA Duke Institute for Brain Sciences Duke University School of MedicineDurhamNCUSA Duke Cancer Institute Duke University School of MedicineDurhamNCUSA

The neurovascular unit and stem cell therapy in ischemic stroke:Ischemic stroke,accounts for approximately 85% of all stroke incidents and is a major global health *** is the leading cause of disability and death worldwide,posing immense societal and economic challenges due to the long-term care required for stro ke survivors and the significant healthcare costs associated with its treatment and management(Amarenco et al.,2009).

关键词： death unit

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Acoustofluidic scanning fluorescence nanoscopy with a large field of view

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Microsystems & Nanoengineering 2024年第3期10卷 159-167页

作者： Geonsoo Jin Neil Upreti Joseph Rich Jianping Xia Chenglong Zhao Tony Jun Huang Thomas Lord Department of Mechanical Engineering and Materials Science Duke UniversityDurhamNC 27708USA Department of Biomedical Engineering Duke UniversityDurhamNC 27708USA The MITRE Corporation McLeanVA 22102USA

Large-field nanoscale fluorescence imaging is invaluable for many applications,such as imaging subcellular structures,visualizing protein interactions,and high-resolution tissue ***,conventional fluorescence microscopy requires a trade-off between resolution and field of view due to the nature of the optics used to form the *** overcome this barrier,we developed an acoustofluidic scanning fluorescence nanoscope that simultaneously achieves superior resolution,a large field of view,and strong fluorescent *** acoustofluidic scanning fluorescence nanoscope utilizes the superresolution capabilities of microspheres that are controlled by a programmable acoustofluidic device for rapid fluorescence enhancement and *** acoustofluidic scanning fluorescence nanoscope resolves structures that cannot be resolved with conventional fluorescence microscopes with the same objective lens and enhances the fluorescent signal by a factor of~5 without altering the field of view of the *** improved resolution realized with enhanced fluorescent signals and the large field of view achieved via acoustofluidic scanning fluorescence nanoscopy provides a powerful tool for versatile nanoscale fluorescence imaging for researchers in the fields of medicine,biology,biophysics,and biomedical engineering.

关键词： field resolution utilize

Olfactory immune response to SARS-CoV-2

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Cellular & Molecular Immunology 2024年第2期21卷 134-143页

作者： Sebastian A.Wellford E.Ashley Moseman Department of Integrative Immunobiology Duke University School of MedicineDurhamNCUSA

Numerous pathogens can infect the olfactory tract,yet the pandemic caused by SARS-CoV-2 has strongly emphasized the importance of the olfactory mucosa as an immune *** in the nasal passages,the olfactory mucosa is directly exposed to the environment to sense airborne odorants;however,this also means it can serve as a direct route of entry from the outside world into the *** a result,olfactotropic infections can have serious consequences,including dysfunction of the olfactory system,CNS invasion,dissemination to the lower respiratory tract,and transmission between *** research has shown that a distinctive immune response is needed to protect this neuronal and mucosal tissue.A better understanding of innate,adaptive,and structural immune barriers in the olfactory mucosa is needed to develop effective therapeutics and vaccines against olfactotropic microbes such as ***,we summarize the ramifications of SARS-CoV-2 infection of the olfactory mucosa,review the subsequent immune response,and discuss important areas of future research for olfactory immunity to infectious disease.

关键词： Mucosal immunology Neuroimmunology Infectious Disease Sars-CoV-2

GRP7 phase separation as an interpreter of temperature cues

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Molecular Plant 2024年第6期17卷 842-844页

作者： Sunita Pathak Lucia C.Strader Department of Biology Duke UniversityDurhamNCUSA

Plants are exposed to a range of daily and seasonal temperatures and thus are required to regulate their cellular processes under fluctuating temperature *** various temperature-responsive genes,GLYCINE-RICH RNA BINDING PROTEIN7(GRP7)encodes a glycine-rich RNA-binding protein that provides freezing tolerance to plants(Carpenter et al.,1994;Kim et al.,2008)by acting as an RNA chaperone(Kwak et al.,2011).

关键词： conditions. separation

Robot-Oriented 6G Satellite-UAV Networks: Requirements, Paradigm Shifts, and Case Studies

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China Communications 2024年第2期21卷 74-84页

作者： Peng Wei Wei Feng Yunfei Chen Ning Ge Wei Xiang Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Department of Engineering University of DurhamDH13LEDurhamUK School of Computing Engineering and Mathematical SciencesLa Trobe UniversityMelbourneVIC 3086Australia

Networked robots can perceive their surroundings, interact with each other or humans,and make decisions to accomplish specified tasks in remote/hazardous/complex environments. Satelliteunmanned aerial vehicle(UAV) networks can support such robots by providing on-demand communication services. However, under traditional open-loop communication paradigm, the network resources are usually divided into user-wise mostly-independent links,via ignoring the task-level dependency of robot collaboration. Thus, it is imperative to develop a new communication paradigm, taking into account the highlevel content and values behind, to facilitate multirobot operation. Inspired by Wiener’s Cybernetics theory, this article explores a closed-loop communication paradigm for the robot-oriented satellite-UAV network. This paradigm turns to handle group-wise structured links, so as to allocate resources in a taskoriented manner. It could also exploit the mobility of robots to liberate the network from full coverage,enabling new orchestration between network serving and positive mobility control of robots. Moreover,the integration of sensing, communications, computing and control would enlarge the benefit of this new paradigm. We present a case study for joint mobile edge computing(MEC) offloading and mobility control of robots, and finally outline potential challenges and open issues.

关键词： closed-loop communication mobility control satellite-UAV network structured resource allocation

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Thermodynamic analysis of metal segregation in dual phase high entropy ceramics

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Journal of Materiomics 2024年第4期10卷 889-895页

作者： Steven M.Smith II William G.Fahrenholtz Gregory E.Hilmas Stefano Curtarolo Missouri university of Science and Technology Materials Science and Engineering DepartmentRollaMO65409USA Duke university Department of Mechanical Engineering and Materials ScienceDurhamNC27708USA Duke university Center of Autonomous Materials DesignDurhamNC27708USA

Equilibrium Gibbs'free energy calculations were used to determine metal segregation trends between boride and carbide solid solutions containing two metals that are relevant to dual phase high entropy *** model predicted that Ti had the strongest tendency to segregate to the boride phase followed by Zr,Nb,Mo,V,Hf,and Ta,which matches experimental results of measured *** ratio of a metal in the carbide phase to the content of the same metal in the corresponding metal boride had a linear trend with the change in standard Gibbs'free energy of reaction for a metal carbide reacting with B_(4)C to produce its corresponding metal boride and *** proposed model was used to predict the changes in standard Gibbs'free energy for CrC→CrB_(2) to be−260 kJ and WC→WB_(2) to be 148 kJ,which indicates that Cr has the strongest segregation to the boride and W has the strongest segregation to the *** proposed model can be used to estimate the segregation of metals in dual phase high entropy boride-carbide ceramics of any boride/carbide ratio or metal content.

关键词： Dual phase High entropy ceramic Boride Carbide Thermodynamics

Communication-centric integrated sensing and communications with mixed fields

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Science China(Information Sciences) 2024年第11期67卷 369-370页

作者： Yun XIAO Enhao WANG Yunfei CHEN Hongjian SUN Aissa IKHLEF Department of Engineering Durham University

Integrated sensing and communications(ISAC) is expected to play a vital role in the sixth-generation(6G) wireless networks [1]. By utilizing high frequencies, extremely largescale antenna arrays, and new antenna designs, the 6Gempowered ISAC faces several new challenges, one of which is the considerable near-field(NF) region [1]. Compared with far-field(FF) plane wave model, the NF model assumes spherical wave. This will affect beamforming(BF)designs in ISAC. Most previous works on ISAC beamforming assume the traditional FF model [2].

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