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Structures and ion transport mechanisms of plant high-affinity potassium transporters

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Molecular Plant 2024年第3期17卷 409-422页

作者： Jiangqin Wang Yanping Luo Fan ye Zhong Jie Ding Shao Jian Zheng Shuai Qiao yong Wang Jiangtao Guo Wei Yang Nannan Su international Institutes of Medicine the Fourth Affiliated HospitalZhejang University School of MedicineYiwuZhejiang 322000China Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital Zhejiang University School of MedicineHangzhouZhejang 310058China State Key Laboratory of Plant Environmental Resilience College of Life SciencesZhejang UniversityHangzhouZhejang 310058China College of Life Sciences Zhejiang UniversityHangzhouZhejiang 310058China NHC and CAMS Key Laboratory of Medical Neurobiology MOE Frontier Science Center for Brain Science and Brain-machine IntegrationSchool of Brain Science and Brain MedicineZhejiang UniversityHangzhouZhejiang 310058China Nanhu Brain-computer Interface Institute Hangzhou.Zheiang 311100.China

Plant high-affinity K^(+) transporters(HKTs)mediate Na^(+) and K^(+) uptake,maintain Na^(+)/K^(+) homeostasis,and therefore play crucial roles in plant salt *** this study,we present cryoelectron microscopy structures of HKTs from two classes,classI HKT1;1 from Arabidopsis thaliana(AtHKT1;1)and class II HKT2;1 from Triticum aestivum(TaHKT2;1),in both Na^(+) -and K^(+) -bound states at 2.6-to 3.0-A ***1;1and TaHKT2;1function *** HKT subunit consists of four tan-dem domain units(D1-D4)with a repeated K^(+) -channel-like M-P-M *** each subunit,D1-D4 assemble into an ion conduction pore with a pseudo-four-fold *** both TaHKT2;1and AtHKT1;1 have only one putative Na^(+) ion bound in the selectivity filter with a similar coordination pattern,the two HKTs display different K^(+) binding modes in the ***2;1 has three K^(+) ions bound in the selec-tivity filter,but AtHKT1;1 has only two K^(+) ions bound in the filter,which has a narrowed external entrance due to the presence of a Ser residue in the first filter *** structures,along with compu-tational,mutational,and electrophysiological analyses,enable us to pinpoint key residues that are critical for the ion selectivity of *** findings provide new insights into the ion selectivity and ion transport mechanisms of plant HKTs and improve our understanding about how HKTs mediate plant salt tolerance and enhance crop growth.

关键词： HKTs structure ion selectivity mechanism salt tolerance

Multi-stimuli-responsive aggregation-induced emission copper iodide cluster

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Science China Chemistry 2024年第4期67卷 1193-1197页

作者： Bo Li Yuan-Yuan Liu Peng Luo ye-Ru Liu Ying-jun Chen Kai Li Shuang-Quan Zang College of Chemistry and Pharmacy Engineering Nanyang Normal UniversityNanyang 473061China Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhou 450001China

Stimuli-responsive luminescent materials have attracted significant attention in the development of smart photoactive materials for both fundamental research and technological *** this work,a new copper iodide cluster(1)with aggregationinduced emission(AIE)characteristic,was obtained combining Cu_(4)I_(4) core with rhodamine B derivative ligand.1 has reversible and distinct multi-stimuli-responsive luminescence for external temperature,volatile organic compound,and mechanical ***,1 exhibited unusual large blue shift(84 nm)after being ground,which originated from the change of intermolecular ***,1 exhibits high oxygen quenching efficiency for 82.2% at 1 *** studies showed that the multi-stimuli-responsive luminescence properties of 1 can be attributed to the regulation of cluster-centered luminescence process,metal-to-ligand charge transfer process,halide-to-metal charge transfer luminescence process and aggregationinduced barrier to oxygen *** work not only reports an AIE copper iodide cluster,but also provides a new strategy to develop multi-stimuli-responsive luminescence materials.

关键词： copper iodide cluster aggregation-induced emission multi-stimuli-response

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Anomalous thermal expansion and enhanced magnetocaloric effect in<001>-textured Mn_(x)Fe_(5-x)Si_(3) alloys

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Rare Metals 2024年第5期43卷 2263-2274页

作者： yong Gong Xue-Fei Miao Tapas Samanta Chris Taake jun Liu Feng-Jiao Qian Yan-Yan Shao Yu-Jing Zhang Qing-yong Ren Luana Caron Feng Xu MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials Technology School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing210094China Department of Physics Bielefeld University33501BielefeldGermany College of Physics Nanjing University of Aeronautics and AstronauticsNanjing210016China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China Spallation Neutron Source Science Center Dongguan523803China Guangdong-Hong Kong-Macao Joint Laboratory for Neutron Scattering Science and Technology Dongguan523803China Department of Physics Bielefeld University33501BielefeldGermany Helmholtz-Zentrum Berlin für Materialien und Energie12489BerlinGermany

The development of zero and negative therma expansion(i.e.,ZTE and NTE)materials is of crucial importance to the control of undesirable thermal expansion for high-precision *** the present work,ZTE and NTE were obtained in directionally-solidified Mn_(x)Fe_(5-x)Si_(3)alloys with a strongtexture,in striking contrast to positive thermal expansion in their isotropic counterparts Magnetometry and in-situ X-ray diffraction(XRD)measurements were performed to uncover the origin of the anomalous thermal *** measurements indicate a strong easy-plane magnetocrystalline anisotropy in the textured samples,where the magnetic moments are aligned within the ab plane of the hexagonal structure Temperature-dependent XRD on the x=1 sample reveals a ZTE character in the ab plane that is coupled to a ferromagnetic *** a result,the macroscopic ZTE(~0.22×10^(-6)K^(-1))in the x=1 sample can be attributed to the microscopic magneto volume effect within the ab plane,which is realized by the introduction of the-textured ***,the competition between antiferromagnetic and ferromagnetic exchange coupling leads to NTE in textured x=1.5 and 2 ***,textured x=1 sample displays enhanced magnetocaloric properties as compared to the conventional counterparts with randomly-oriented *** this work demonstrates a new strategy toward the exploration of anomalous thermal expansion properties as well as the enhancement of magnetocaloric properties for materials with a strong magnetocrystalline anisotropy.

关键词： MnFeySis Magnetocaloric effect Magnetic phase transition Negative thermal expansion

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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极端天气对风电场局地风环境的影响

华中科技大学学报(自然科学版) 2024年第7期52卷 106-112页

作者：郜志腾张军李岳李晔上海交通大学船舶海洋与建筑工程学院成都流体动力创新中心

以东南沿海某风电场24台兆瓦级风电机组为例，基于中尺度数值模式并结合风电场参数化模型，对台风天气下该风电场局地风速、风向、风功率密度、湍动能等特征量的时序演变特征和空间分布特性进行分析．结果表明：数值模拟结果与观测结果... 详细信息

以东南沿海某风电场24台兆瓦级风电机组为例，基于中尺度数值模式并结合风电场参数化模型，对台风天气下该风电场局地风速、风向、风功率密度、湍动能等特征量的时序演变特征和空间分布特性进行分析．结果表明：数值模拟结果与观测结果平均误差在1 m/s以内；未受台风影响时风电场在轮毂高度处速度亏损最大，垂向上尾流影响范围在3倍轮毂高度左右；受台风影响时，风电场尾流受台风强迫作用而呈现尾流偏转效应，尾流最大偏转角可达33°；风电场尾流会增加附近区域的湍动能水平，在水平方向上影响区域持续至下游4～8倍风场直径，在垂向上影响范围可达3.5倍轮毂高度处．风电场下游较远处湍动能分布受下垫面、风电场尾流和极端风况的耦合调制作用，进而呈现典型的大尺度旋涡绕流结构．

关键词：极端天气大气环境风电场风资源中尺度模式

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Proppant transport in rough fracture networks using supercritical CO_(2)

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Petroleum Science 2024年第3期21卷 1852-1864页

作者： yong Zheng Meng-Meng Zhou Ergun Kuru Bin Wang jun Ni Bing Yang Ke Hu Hai Huang Hai-Zhu Wang School of Petroleum Engineering Xi'an Shiyou UniversityXian710065ShaanxiChina Shaanxi Key Laboratory of Carbon Dioxide Sequestration and Enhanced Oil Recovery Xi'an710075ShaanxiChina State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China School of Mining and Petroleum Engineering University of AlbertaEdmontonTG2W2AlbertaCanad Shaanxi Yanchang Petroleum(Group)Co. Ltd.Xi'an710075ShaanxiChina

Proppant transport within fractures is one of the most critical tasks in oil,gas and geothermal reservoir stimulation,as it largely determines the ultimate performance of the operating *** transport in rough fracture networks is still a relatively new area of research and the associated transport mechanisms are still *** this study,representative parameters of rough fracture surfaces formed by supercritical CO_(2) fracturing were used to generate a rough fracture network model based on a spectral synthesis *** fluid dynamics(CFD)coupled with the discrete element method(DEM)was used to study proppant transport in this rough fracture *** reveal the turning transport mechanism of proppants into branching fractures at the intersections of rough fracture networks,a comparison was made with the behavior within smooth fracture networks,and the effect of key pumping parameters on the proppant placement in a secondary fracture was *** results show that the transport behavior of proppant in rough fracture networks is very different from that of the one in the smooth fracture *** turning transport mechanisms of proppant into secondary fractures in rough fracture networks are gravity-driven sliding,high velocity fluid suspension,and fracture structure *** the same injection conditions,supercritical CO_(2)with high flow Reynolds number still has a weaker ability to transport proppant into secondary fractures than *** of the supercritical CO_(2)needs to be increased beyond a certain value to have a significant effect on proppant carrying,and under the temperature and pressure conditions of this paper,it needs to be increased more than 20 times(about 0.94 m Pa s).Increasing the injection velocity and decreasing the proppant concentration facilitates the entry of proppant into the branching fractures,which in turn results in a larger stimulated reservoir *** results help to understand the pro

关键词： Reservoir stimulation CCUS Rough fracture network Supercritical CO_(2) Proppanttransport

Clinical pathological characteristics of“crawling-type”gastric adenocarcinoma cancer:A case report

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1660-1667页

作者： yong-Wei Xu Yan Song jun Tian Ba-Cui Zhang Yu-Sheng Yang Jing Wang Department of Gastroenterology Songjiang HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 201600China Department of Pathology Songjiang HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 201600China

BACKGROUND Gastric cancer(GC)is a significant health problem worldwide,and early detection and accurate diagnosis are crucial for improving patient ***-type gastric adenocarcinoma is a rare subtype of GC that has unique histopathological and clinical characteristics,and its diagnosis and management can be *** pathological type of GC is also *** SUMMARY Here,we report the case of a patient who underwent ordinary endoscopy,na-rrow-band imaging,and endoscopic ultrasonography intending to determine the extent of tumor invasion and upper abdominal enhanced computed tomography and whether there was tumor ***,endoscopic submucosal dissection was *** pathological and immunohistochemical examination,the pathological diagnosis was crawling-type gastric *** is a very rare and special pathological type of *** case highlights the importance of using advanced endoscopic techniques and pathological examination in diagnosing and managing gastric crawling-type ***,the findings underscore the need for continued research and clinical experience in this rare subtype of GC to improve patient *** The“crawling-type”GC is a rare and specific tumor *** is difficult to identify and diagnose gliomas via *** tumor is ill-defined,with a flat appearance and indistinct borders due to the lack of contrast against the background *** revealed that the tumor cells were hand-like,so the patient has diagnosed with“crawling-type”gastric adenocarcinoma.

关键词： Clinicopathological Crawling-type gastric Pathology Gastric cancer Gastric adenocarcinoma cancer Case report

Spatially explicit reconstruction of cropland cover in Europe from AD 1800 to 2000

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Science China Earth Sciences 2024年第9期67卷 2953-2971页

作者： jun LI Yu ye Xiuqi FANG Diyang ZHANG Zhilei WU Faculty of Geographical Science Beijing Normal University Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal University College of Geographical Science Qinghai Normal University

One of the challenges in global change research is the significant uncertainty in global historical land use and land cover(LUCC) datasets, which are widely used as foundational data. In addition to the regional cropland area reconstructions,improving the grid allocation method is another feasible way to raise the reliability of historical LUCC data. In this study, an integrated reconstruction of the national cropland areas over the past 200 years was developed for 36 European countries. After that, the allocation algorithm was built using physiogeographic variables and historical city sites for accounting for land suitability and cultivation preferences, respectively. Finally, cropland data in Europe with a spatial resolution of 5′×5′ at five time sections from AD 1800 to 2000 were generated using the optimal allocation algorithm in accordance with the stages of the regional history. The results were as follows:(1) The dominant factors governing the distribution of croplands in Europe vary at different agricultural stages, but the results can be merged together. Land suitability was more optimal for allocation during the modern agricultural stage(AD 1950 and 2000); the priority index combined with land suitability and cultivation preference was more reasonable for allocation during the traditional agricultural stage(AD 1800). The average of the allocations by priority index and the land suitability could be adopted as the allocation results during the transitional stage(AD 1850 and 1900) because the grids for absolute differences within ±10 and ±20 percentage points between the results obtained from the above two allocations were above 80% and 95%, respectively, which means the two allocation results could be merged.(2) Over the past200 years, the total cropland area in Europe first increased to a peak in AD 1900 and then decreased. Spatially, the centre of the higher cropland fraction shifted from the western part of Europe in AD 1800 to the eastern part of the co

关键词： Land use and land cover change Historical cropland Gridding allocation Europe Past 200 years

Accelerating Asteroidal Period and Pole Inversion from Multiple Lightcurves Using Parallel Differential Evolution and Cellinoid Shape Model

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Research in Astronomy and Astrophysics 2024年第4期24卷 271-286页

作者： yong-Xiong Zhang Wen-Xiu Guo Xiao-Ping Lu Hua Zheng Hai-Bin Zhao jun Tian Wei-Lin Wang School of Engineering Guangzhou College of Technology and BusinessGuangzhou 510850China School of Computer Science and Engineering Macao University of Science and TechnologyTaipaMacao 999078China School of Mathematics and Statistics Shaoguan UniversityShaoguan 512099China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China Key Laboratory of Planetary Sciences Purple Mountain ObservatoryCASNanjing 210023China

Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally *** paper presents a new approach that combines a simplified Cellinoid shape model with the Parallel Differential Evolution(PDE)algorithm to accelerate *** PDE algorithm is more efficient than the Differential Evolution algorithm,achieving an extraordinary speedup of 37.983 with 64 workers on multicore *** PDE algorithm accurately derives period and pole values from simulated *** analysis of real asteroid lightcurves validates the method’s reliability:in comparison with results published elsewhere,the PDE algorithm accurately recovers the rotational periods and,given adequate viewing geometries,closely matches the pole *** PDE approach converges to solutions within 20,000 iterations and under one hour,demonstrating its potential for large-scale data *** work provides a promising new tool for unveiling asteroid physical properties by overcoming key computational bottlenecks.

关键词： methods:numerical minor planets asteroids:general techniques:photometric astrom