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Factor analysis of recent major heatwaves in east Asia

Geoscience Frontiers 2024年第1期15卷 374-383页

作者： Arim Yoon jeongwon Kim Jooyeop Lee Hyun Min Sung je-woo Hong Seung-Ki Min Junhong Lee Jinkyu Hong ecosystem-Atmosphere Process Laboratory Department of Atmospheric SciencesYonsei UniversitySeoul 03722Republic of Korea National Institute of meteorological Sciences Jeju 63568Republic of Korea Korea Adaptation Center for Climate Korea Environment InstituteSejong 30121Republic of Korea Division of environmental Science and engineering Pohang University of Science and TechnologyPohang 37673Republic of Korea Max Planck Institute for meteorology Hamburg 20146Germany Institute for Convergence Research and education in Advanced Technology Yonsei UniversitySeoulRepublic of Korea

Heatwaves(Hws)present a major hazard to our society and more extreme heatwaves are expected with future climatic ***,it is important to improve our understanding of the underlying processes that drive Hws,in order to boost our socioeconomic-ecological *** this study,we quantified the influences of key driving factors(large-scale atmospheric circulation,soil moisture,and sea surface temperature)and their synergies on recent heatwaves in east *** conducted a factor separation analysis for three recent Hw events by constraining the key factors in the regional weather Research and Forecasting model with their climatologies or pseudo-observations in different *** study showed distinct spatial variations in the Hw-controlling factors in east *** synergistic interaction of large-scale circulation and soil moisture was the most important factors in the 2013 Chinese *** the 2018 Hws in Korea and Japan,the same stagnant large-scale atmospheric circulation played a dominant role in driving the Hw *** land-atmosphere coupling via soil moisture,its interaction with circulation,and SST exhibited stronger influences during the Korean Hw than the Japanese *** analysis also revealed temporal variations in the factors driving Korean and Chinese Hws due to typhoon passage and other multiple processes over heterogeneous surfaces(i.e.,topographically induced Foehn winds,large-scale warm advection from the warm ocean,spatial differences in soil moisture).Our findings suggest that future heatwave-related studies should consider interactive contributions of key factors,their interplay with surface heterogeneities of complex terrain.

关键词： Heatwave east Asia Large-scale circulation Soil moisture Sea surface temperature Synergistic impacts

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Lax-Oleinik-Type Formulas and efficient Algorithms for Certain High-Dimensional Optimal Control Problems

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1428-1471页

作者： Paula Chen jerome Darbon Tingwei meng Division of Applied Mathematics Brown UniversityProvidenceRIUSA Department of Mathematics UCLALos AngelesCAUSA

Two of the main challenges in optimal control are solving problems with state-dependent running costs and developing efficient numerical solvers that are computationally tractable in high *** this paper,we provide analytical solutions to certain optimal control problems whose running cost depends on the state variable and with constraints on the *** also provide Lax-Oleinik-type representation formulas for the corresponding Hamilton-Jacobi partial differential equations with state-dependent ***,we present an efficient,grid-free numerical solver based on our representation formulas,which is shown to scale linearly with the state dimension,and thus,to overcome the curse of *** existing optimization methods and the min-plus technique,we extend our numerical solvers to address more general classes of convex and nonconvex initial *** demonstrate the capabilities of our numerical solvers using implementations on a central processing unit(CPU)and a field-programmable gate array(FPGA).In several cases,our FPGA implementation obtains over a 10 times speedup compared to the CPU,which demonstrates the promising performance boosts FPGAs can *** numerical results show that our solvers have the potential to serve as a building block for solving broader classes of high-dimensional optimal control problems in real-time.

关键词： Optimal control Hamilton-Jacobi partial differential equations Grid-free numerical methods High dimensions Field-programmable gate arrays(FPGAs)

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Unilateral rNurr1-V5 transgene expression in nigral dopaminergic neurons mitigates bilateral neuropathology and behavioral deficits in parkinsonian rats withα-synucleinopathy

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Neural Regeneration Research 2024年第9期19卷 2057-2067页

作者： Bismark Gatica-Garcia Michael J.Bannon Irma Alicia Martínez-Dávila Luis O.Soto-Rojas David Reyes-Corona Lourdes escobedo Minerva Maldonado-Berny me Gutierrez-Castillo Armando J.espadas-Alvarez Manuel A.Fernandez-Parrilla Juan U.Mascotte-Cruz CP Rodríguez-Oviedo Irais e.Valenzuela-Arzeta Claudia Luna-Herrera Francisco e.Lopez-Salas Jaime Santoyo-Salazar Daniel Martinez-Fong Departamento de Fisiología Biofísica y NeurocienciasCentro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico Department of Pharmacology Wayne State University School of MedicineDetroitMIUSA Laboratorio de Patogénesis Molecular Carrera Médico CirujanoFacultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantla de BazMéxico Red de medicina para la educación y Desarrollo y la Investigación Científica de Iztacala(Red meDICI) Carrera Médico CirujanoFacultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantla de BazMéxico Nanoparticle Therapy Institute AguascalientesMéxico Departamento de Biociencias e Ingeniería Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y DesarrolloInstituto Politécnico NacionalCiudad de MéxicoMéxico escuela Nacional de medicina y Homeopatía Instituto Politécnico NacionalCiudad de MéxicoMéxico Departamento de Fisiología Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCiudad de MéxicoMéxico Departamento de Biología Molecular y Biotecnología Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMéxico Departamento de Física Centro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico Programa de Nanociencias y Nanotecnología Centro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico

Parkinsonism by unilateral,intranigralβ-sitosterolβ-D-glucoside administration in rats is distinguished in that theα-synuclein insult begins unilaterally but spreads bilaterally and increases in severity over time,thus replicating several clinical features of Parkinson’s disease,a typicalα-*** Nurr1 repressesα-synuclein,we evaluated whether unilateral transfected of rNurr1-V5 transgene via neurotensin-polyplex to the substantia nigra on day 30 after unilateralβ-sitosterolβ-D-glucoside lesion could affect bilateral neuropathology and sensorimotor deficits on day 30 *** study found that rNurr1-V5 expression but not that of the green fluorescent protein(the negative control)reducedβ-sitosterolβ-D-glucoside-induced ***,a bilateral increase in tyrosine hydroxylase-positive cells and arborization occurred in the substantia nigra and increased tyrosine hydroxylase-positive ramifications in the *** addition,tyrosine hydroxylase-positive cells displayed less senescence markerβ-galactosidase and more neuron-cytoskeleton markerβIII-tubulin and brain-derived neurotrophic factor.A significant decrease in activated microglia(positive to ionized calcium-binding adaptor molecule 1)and neurotoxic astrocytes(positive to glial fibrillary acidic protein and complement component 3)and increased neurotrophic astrocytes(positive to glial fibrillary acidic protein and S100 calcium-binding protein A10)also occurred in the substantia *** effects followed the bilateral reduction inα-synuclein aggregates in the nigrostriatal system,improving sensorimotor *** results show that unilateral rNurr1-V5 transgene expression in nigral dopaminergic neurons mitigates bilateral neurodegeneration(senescence and loss of neuron-cytoskeleton and tyrosine hydroxylase-positive cells),neuroinflammation(activated microglia,neurotoxic astrocytes),α-synuclein aggregation,and sensorimotor *** neurotrophic astrocytes and

关键词： A1 astrocytes A2 astrocytes gene therapy microglia motor deficits nanoparticles neurodegeneration neuroinflammation senescence α-synuclein aggregates

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Artificial optoelectronic synapse based on spatiotemporal irradiation to source-sharing circuitry of synaptic phototransistors

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InfoMat 2024年第2期6卷 131-141页

作者： Seungho Song Changsoon Choi Jongtae Ahn je-Jun Lee Jisu Jang Byoung-Soo Yu Jung Pyo Hong Yong-Sang Ryu Yong-Hoon Kim Do Kyung Hwang Center for Opto-electronic Materials and Devices Post-Silicon Semiconductor InstituteKorea Institute of Science and Technology(KIST)SeoulRepublic of Korea School of Advanced Materials Science and engineering Sungkyunkwan UniversitySuwonRepublic of Korea Center for Spintronics Post-Silicon Semiconductor InstituteKorea Institute of Science and Technology(KIST)SeoulRepublic of Korea Division of Nanoscience&Technology KIST SchoolUniversity of Science and Technology(UST)SeoulRepublic of Korea School of Biomedical engineering Korea UniversitySeoulRepublic of Korea KU-KIST Graduate School of Converging Science and Technology Korea UniversitySeoulRepublic of Korea

To overcome the intrinsic inefficiency of the von Neumann architecture,neuromorphic devices that perform analog vector–matrix multiplication have been highlighted for achieving power-and time-efficient data *** particular,artificial synapses,of which conductance should be programmed to represent the synaptic weights of the artificial neural network,have been intensively researched to realize neuromorphic ***,inspired by excitatory and inhibitory synapses,we develop an artificial optoelectronic synapse that shows both potentiation and depression characteristics triggered only by optical *** design of the artificial optoelectronic synapse,in which excitatory and inhibitory synaptic phototransistors are serially connected,enables these characteristics by spatiotemporally irradiating the phototransistor channels with optical ***,a negative synaptic weight can be realized without the need for electronic components such as *** such attributes,the artificial optoelectronic synapse is demonstrated to classify three digits with a high recognition rate(98.3%)and perform image preprocessing via analog vector-matrix multiplication.

关键词： amorphous oxide semiconductor analog processing artificial synapse neuromorphic optoelectronics

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Are hydrides under high-pressure-high-temperature superconductors?

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National Science Review 2024年第7期11卷 9-12页

作者： J.e.Hirsch Department of Physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the field should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides

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Highly elastic,Bioresorbable Polymeric Materials for Stretchable,Transient electronic Systems

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Nano-Micro Letters 2024年第6期16卷 1-13页

作者： jeong‑woong Shin Dong‑je Kim Tae‑Min Jang won Bae Han Joong Hoon Lee Gwan‑Jin Ko Seung Min Yang Kaveti Rajaram Sungkeun Han Heeseok Kang Jun Hyeon Lim Chan‑Hwi eom Amay J.Bandodkar Hanul Min Suk‑won Hwang KU‑KIST Graduate School of Converging Science and Technology Korea University145 Anam‑roSeongbuk‑guSeoul 02841Republic of Korea SK Hynix 2091Gyeongchung‑daeroBubal‑eupIcheon‑siGyeonggi‑do 17336Republic of Korea Hanwha Systems Co. Ltd.188Pangyoyeok‑roBundang‑guSeongnam‑siGyeonggi‑do 13524Republic of Korea Department of electrical and Computer engineering North Carolina State UniversityRaleighNC 27606USA Center for Advanced Self‑Powered Systems of Integrated Sensors and Technologies(ASSIST) North Carolina State UniversityRaleighNC 27606USA Department of Integrative energy engineering Korea University145 Anam‑roSeongbuk‑guSeoul 02841Republic of Korea Biomaterials Research Center Korea Institute of Science and Technology(KIST)5 Hwarang‑ro 14‑gilSeongbuk‑guSeoul 02792Republic of Korea Semiconductor R&D Center Samsung Electronics Co.Ltd.Hwaseong‑siGyeonggi‑do 18448Republic of Korea Center for Advanced Biomolecular Recognition Biomedical Research DivisionKorea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea

Substrates or encapsulants in soft and stretchable formats are key components for transient,bioresorbable electronic systems;however,elastomeric polymers with desired mechanical and biochemical properties are very limited compared to nontransient ***,we introduce a bioresorbable elastomer,poly(glycolide-co-ε-caprolactone)(PGCL),that contains excellent material properties including high elongation-at-break(esilience and toughness,and tunable dissolution *** of PGCLs as polymer matrices,in combination with conducing polymers,yields stretchable,conductive composites for degradable interconnects,sensors,and actuators,which can reliably function under external *** of device components with wireless modules demonstrates elastic,transient electronic suture system with on-demand drug delivery for rapid recovery of postsurgical wounds in soft,time-dynamic tissues.

关键词： Biodegradable elastomer Conductive polymer composites Biomedical device Transient electronics

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Functionally graded structure of a nitride-strengthened Mg_(2)Si-based hybrid composite

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Journal of Magnesium and Alloys 2024年第3期12卷 1239-1256页

作者： jeongho Yang woongbeom Heogh Hogi Ju Sukhyun Kang Tae-Sik Jang Hyun-Do Jung Mohammad Jahazi Seung Chul Han Seong je Park Hyoung Seop Kim Susmita Bose Amit Bandyopadhyay Martin Byung-Guk Jun Young won Kim Dae-kyeom Kim Rigoberto CAdvincula Clodualdo Aranas Jr Sang Hoon Kim School of mechanical engineering Pusan National UniversityBusan 46241Republic of Korea Department of mechanical Design engineering Hanyang UniversitySeoul 04763Republic of Korea Process Research 3 Team LG Display Co.Ltd.PajuGyeonggi-do 10845Republic of Korea Department of Materials Science and engineering Chosun UniversityGwangju 61452Republic of Korea Institute of well-Aging medicare&Chosun University LAMP Center Chosun UniversityGwangju 61452Republic of Korea Division of Materials Science and engineering Hanyang UniversitySeoul 04763Republic of Korea Department of mechanical engineering École de Technologie SupérieureMontrealQuebec H3C 1K3Canada Material&Component Convergence R&D Center Korea Construction Equipment Technology InstituteGunsanJeollabuk-do 54002Republic of Korea School of mechanical and Aerospace engineering Nanyang Technological UniversitySingapore 639798Singapore Graduate Institute of Ferrous&eco Materials Technology Pohang University of Science and TechnologyPohangGyeongsangbuk-do 37673Republic of Korea Advanced Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Institute for Convergence Research and education in Advanced Technology Yonsei UniversitySeoul 03722Republic of Korea School of mechanical and Materials engineering Washington State UniversityPullmanWashington 99164USA School of mechanical engineering Purdue UniversityWest LafayetteIndiana 47907USA Research Institute of Advanced Manufacturing Technology Korea Institute of Industrial TechnologyIncheon 21999Republic of Korea Department of Macromolecular Science and engineering Case Western Reserve UniversityClevelandOhio 44106USA Department of Chemical and Biomolecular engineering and Joint Institute for Advanced Materials University of TennesseeKnoxvilleTennessee 37996USA Center for Nanophase Materials and Sciences Oak Ridge National LaboratoryOak RidgeTennessee 37830USA Department of mechanical engineering University of New BrunswickFrederictonNew Brunswick E3B 5A3Cana

The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in order to provide ultimate wear resistance based on the laser-irradiation-induced inclusion of N_(2) gas during laser powder bed *** is substantialized based on both the thermal diffusion-and chemical reactionbased metallurgy of the Mg_(2)Si–SiC/nitride hybrid *** study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-dependent architectonics during additive *** strategy enables the development of a compositional gradient from the center to the edge of each melt pool of the Mg_(2)Si–SiC/nitride hybrid ***,the coefficient of friction of the hybrid composite exhibits a 309.3%decrease to–1.67 compared to–0.54 for the conventional nonreinforced Mg_(2)Si structure,while the tensile strength exhibits a 171.3%increase to 831.5 MPa compared to 485.3 MPa for the conventional *** outstanding mechanical behavior is due to the(1)the complementary and synergistic reinforcement effects of the SiC and nitride compounds,each of which possesses an intrinsically high hardness,and(2)the strong adhesion of these compounds to the Mg_(2)Si matrix despite their small sizes and low concentrations.

关键词： Laser powder bed fusion Mg_(2)Si-SiC/nitride hybrid composite Both the thermal diffusion-and chemical reaction-based metallurgy Functionally graded structure Compositional gradient wear resistance.

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Strong coupling and catenary field enhancement in the hybrid plasmonic metamaterial cavity and TMDC monolayers

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Opto-electronic Advances 2024年第5期7卷 20-32页

作者： Andergachew mekonnen Berhe Khalil As’ham Ibrahim Al-Ani Haroldo T.Hattori Andrey e.Miroshnichenko School of engineering and Technology University of New South Wales at CanberraNorthcott DriveCanberra ACT 2610Australia

Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy *** plasmon-exciton strong coupling,plasmonic nanocavities play a significant role due to their ability to confine light in an ultrasmall ***,two-dimensional transition metal dichalcogenides(TMDCs) have a significant exciton binding energy and remain stable at ambient conditions,making them an excellent alternative for investigating light-matter *** a result,strong plasmon-exciton coupling has been reported by introducing a single metallic ***,single nanoparticles have lower spatial confinement of electromagnetic fields and limited tunability to match the excitonic ***,we introduce the concept of catenary-shaped optical fields induced by plasmonic metamaterial cavities to scale the strength of plasmon-exciton *** demonstrated plasmon modes of metallic metamaterial cavities offer high confinement and tunability and can match with the excitons of TMDCs to exhibit a strong coupling regime by tuning either the size of the cavity gap or *** calculated Rabi splitting of Au-MoSe_2 and Au-wSe_2 heterostructures strongly depends on the catenary-like field enhancement induced by the Au cavity,resulting in room-temperature Rabi splitting ranging between 77.86 and 320 me *** plasmonic metamaterial cavities can pave the way for manipulating excitons in TMDCs and operating active nanophotonic devices at ambient temperature.

关键词： catenary-shaped field enhancement strong coupling plasmon exciton Rabi splitting

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Spreadability of powders for additive manufacturing:A critical review of metrics and characterisation methods

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Particuology 2024年第10期93卷 211-234页

作者： Fatemeh A.Talebi Zobaideh Haydari Hamid Salehi Mozhdeh mehrabi Jabbar Gardy Mike Bradley Andrew e.Bayly Ali Hassanpour School of Chemical and Process engineering University of LeedsLeedsLS29JTUK School of engineering University of GreenwichGreenwichME44TBUK Cormica Limited Listerhills Science ParkCampus RoadBradfordBD71HRUK

Powder bed fusion methods of additive manufacturing (AM) require consistent, reproducible, and uniform layers of powder for the reliable production of high-quality parts, where properties of powder are central to achieving this. Among these properties, powder flowability and spreadability play critical roles in determining the quality of these powder *** extensive research has been conducted on powder flow and spreading behaviour, and on their characterisation, there is little critical comparison and review of these terms in the context of AM. Such a review is necessary to further develop and enhance our comprehension of spreading dynamics and its relation to powder properties in AM *** review paper aims to build a coherent understanding of the correlation between powder characteristics and spreading in powder based additive manufacturing and its impact on manufactured parts. It highlights the current progress in comprehending spreading dynamics, the influence of powder characteristics, environmental conditions, spreading system, and the development of testing tools to assess powder spreadability. Furthermore, the paper critically discusses the challenge of finding appropriate quantitative metrics and recent advances in the use of standardised methods for evaluating powder spreadability.

关键词： Powder spreading Powder flowability Powder properties Quality of layer and final products

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epidemiologic investigation of pediatric distal humerus fractures: An American insurance claims database study

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world Journal of Orthopedics 2024年第1期15卷 52-60页

作者： Kyle Jay Klahs Jake e Dertinger Grant T mello Kevin Thapa Alexis B Sandler e'Stephan J jesus Garcia Nata Parnes Department of Orthopaedic Surgery Texas Tech University Health Sciences-El PasoEl PasoTX 79905United States medical School California Health Sciences University College of Osteopathic MedicineClovisCA 93611United States Undergraduate School Binghampton UniversityVestalNY 13902United States Department of Orthopaedic Surgery William Beaumont Army Medical CenterFort BlissTX 79918United States Department of Orthopaedic Surgery Carthage Area HospitalCarthageNY 13619United States

BACKGROUND Distal humerus elbow fractures are one of the most common traumatic fractures seen in pediatric patients and present as three main types:Supracondylar(SC),lateral condyle(LC),and medial epicondyle(me)*** To evaluate the epidemiology of pediatric distal humerus fractures(SC,LC,and me)from an American insurance claims *** A retrospective review was performed on patients 17 years and younger with the ICD 9 and 10 codes for SC,LC and me fractures based on the IBM Truven MarketScan®Commercial and IBM Truven MarketScan medicare Supplemental *** from 2015 to 2020 were queried for treatments,patient age,sex,length of hospitalization,and *** A total of 1133 SC,154 LC,and 124 me fractures were *** fractures had the highest percentage of operation at 83%,followed by LC(78%)and me fractures(41%).Male patients were,on average,older than female patients for both SC and me *** In the insurance claims databases used,SC fractures were the most reported,followed by LC fractures,and finally me *** was identified to be a factor for how a pediatric distal humerus fractures,with patients with SC and LC fractures being younger than those with me *** peak age per injury per sex was similar to reported historic central tendencies,despite reported trends for younger physiologic development.

关键词： Supracondylar humerus fracture Lateral condyle fracture medial epicondyle fracture Pediatric elbow Truven epidemiology

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