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Cooperative Spectrum Sensing Based on Centralized Double Threshold in MCN

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China Communications 2020年第5期17卷 235-242页

作者： Hai Huang Junsheng mu Xiaojun jing School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Trustworthy Distributed Computing and Service Ministry of EducationBeijing 100876China

Cooperative spectrum sensing appears popular currently due to its ability to solve the issue of hidden terminal and improve detection performance in Cognitive Radio Networks. Meanwhile, double threshold based energy detector has attracted much attention for its low computational complexity and superior performance. Motivated by this, a cooperative spectrum sensing scheme is proposed in this paper based on centralized double threshold in the maritime communication networks(MCN), where the energy value of received signal in each cognitive node is forwarded to the fusion center for final decision based on double thresholds. Additionally, the proposed scheme is further optimized for the decisions that the energy is within the scope of maximum threshold and minimum threshold. Simulation experiments verify the performance of the proposed method.

关键词： cooperative spectrum sensing double threshold maritime communication network

A Nonlinear Representation of Model Uncertainty in a Convective-Scale Ensemble Prediction System

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Advances in Atmospheric Sciences 2022年第9期39卷 1432-1450页

作者： Zhizhen XU jing CHEN mu mu Guokun DAI Yanan MA Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Numerical Weather Prediction Center China Meteorological AdministrationBeijing 100081China Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081China

How to accurately address model uncertainties with consideration of the rapid nonlinear error growth characteristics in a convection-allowing system is a crucial issue for performing convection-scale ensemble *** this study,a new nonlinear model perturbation technique for convective-scale ensemble forecasts is developed to consider a nonlinear representation of model errors in the Global and Regional Assimilation and Prediction Enhanced System(GRAPES)Convection-Allowing Ensemble Prediction System(CAEPS).The nonlinear forcing singular vector(NFSV)approach,that is,conditional nonlinear optimal perturbation-forcing(CNOP-F),is applied in this study,to construct a nonlinear model perturbation method for *** experiments are performed:One of them is the CTL experiment,without adding any model perturbation;the other two are NFSV-perturbed experiments,which are perturbed by NFSV with two different groups of constraint radii to test the sensitivity of the perturbation magnitude *** results show that the NFSV-perturbed experiments achieve an overall improvement and produce more skillful forecasts compared to the CTL experiment,which indicates that the nonlinear NFSV-perturbed method can be used as an effective model perturbation method for convection-scale ensemble ***,the NFSV-L experiment with large perturbation constraints generally performs better than the NFSV-S experiment with small perturbation constraints in the verification for upper-air and surface weather *** for precipitation verification,the NFSV-S experiment performs better in forecasts for light precipitation,and the NFSV-L experiment performs better in forecasts for heavier precipitation,indicating that for different precipitation events,the perturbation magnitude constraint must be carefully *** the findings above lay a foundation for the design of nonlinear model perturbation methods for future CAEPSs.

关键词： Convection-Allowing Ensemble Prediction System model uncertainty nonlinear forcing singular vector

Advances in bio-inspired electrocatalysts for clean energy future

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Nano Research 2024年第2期17卷 515-533页

作者： jing-Wen Duan mu Min-Rui Gao Division of Nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Electrocatalysis can enable efficient energy storage and conversion and thus is an effective way to achieve carbon *** unique structure and function of organisms can offer many ideas for the design of electrocatalysts,which has become one of the most promising research ***,the understanding of the mechanism of bio-inspired electrocatalysis has become clearer,which has promoted the design of bio-inspired catalysts and catalytic *** bio-inspired catalysts(enzyme-like catalysts,layered porous catalysts,superhydrophobic/superhydrophilic surfaces,and so on)have been developed to enable efficient electrocatalytic ***,we discuss the key advances in the field of bio-inspired electrocatalysts progressed in recent ***,the role of bio-inspiration in increasing the intrinsic activity and number of active sites of catalysts is ***,the structure and mechanism of layered porous catalytic systems that mimic biological transport systems are comprehensively ***,the design of three-phase interfaces from micro-nanoscale to atomic scale is highlighted,including the wettability of the electrode surface and the transport system near the *** conclude the review by identifying challenges in bio-inspired electrocatalysts and providing insights into future prospects for the exciting research field.

关键词： bio-inspired electrocatalysts active sites layered porous structure three-phase interface

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巴西龟代谢性骨病CT诊断病例报告

动物医学进展 2025年第1期46卷 141-144页

作者：孙嘉徐甘靖宇江蓝刘波俞峰中国农业大学北京100193

代谢性骨病(MBD)是一种因钙缺乏或维生素D 3摄入不足引起的骨骼代谢障碍疾病,其临床表现为骨折、脊椎异常、难产、脱垂等症状。计算机断层扫描(CT)在兽医临床中应用的逐渐增加为龟、鳖类MBD提供了新的诊断方式。该病例中红耳巴西龟血检... 详细信息

代谢性骨病(MBD)是一种因钙缺乏或维生素D 3摄入不足引起的骨骼代谢障碍疾病,其临床表现为骨折、脊椎异常、难产、脱垂等症状。计算机断层扫描(CT)在兽医临床中应用的逐渐增加为龟、鳖类MBD提供了新的诊断方式。该病例中红耳巴西龟血检结果提示其肾脏、肝脏功能损害,钙磷代谢异常。CT扫查提示患龟全身组织大面积矿化、背甲凹陷,定量测量患龟背椎骨、神经骨和胸膜骨3处的骨骼密度远低于正常龟,诊断患龟有严重的MBD。治疗方案为对症治疗、改善饲养管理条件,同时对该龟补充维生素D 3。该病例报告系统陈述了龟鳖MBD的诊疗流程,同时表明了CT扫查可为龟鳖MBD精确诊断、治疗和预后提供新的参考。

关键词：龟代谢性骨病计算机断层扫描骨密度

Genome-wide analysis of hippocampal transfer RNA-derived small RNAs identifies new potential therapeutic targets of Bushen Tiansui formula against Alzheimer’s disease

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Journal of Integrative Medicine 2021年第2期19卷 135-143页

作者： Zhe-yu Zhang Chun-hu Zhang jing-jing Yang Pan-pan Xu Peng-ji Yi mu-li Hu Wei-jun Peng Department of Integrated Traditional Chinese&Western Medicine the Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina Department of Integrated Traditional Chinese&Western Medicine Xiangya HospitalCentral South UniversityChangsha 410008Hunan ProvinceChina Department of Scientific Research the Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina

Objective:Bushen Tiansui formula(BSTSF),a traditional Chinese medicine prescription,has been widely used to treat Alzheimer’s disease(AD).However,the mechanisms underlying its effects remain largely *** this study,a rat AD model was used to study the effects of BSTSF on cognitive performance and expression of transfer RNA-derived small RNAs(tsRNAs)in the hippocampus,to determine whether treatment of AD with BSTSF could regulate the expression of tsRNAs,a novel small non-coding ***:To generate a validated AD model,oligomeric amyloid-β_(1-42)(Aβ_(1-42))was injected intracerebroventricularly into *** Morris water maze(MWM)test was used to evaluate rat cognitive performance,and tsRNA-sequencing was conducted to examine tsRNA expression in the rat *** targets were validated by quantitative real-time polymerase chain reaction(qRT-PCR).Bioinformatic analyses were conducted to investigate the biological function of candidate ***:The learning and memory deficits of Aβ_(1-42)-induced AD rats,assessed by MWM tests,were clearly ameliorated by BSTSF treatment.A total of 387 tsRNAs were detected in the rat *** them,13 were significantly dysregulated in AD rats compared with sham control rats,while 57 were markedly altered by BSTSF treatment,relative to untreated AD rats(fold change>2 and Pmultiple signaling pathways and Gene Ontology biological functions,including cyclic adenosine monophosphate and retrograde endocannabinoid ***:This study identified a previously uncharacterized mechanism underlying the effects of BSTSF in alleviating the learning and memory deficits in Aβ_(1-42)-induced AD rats,demonstrating that tsRNAs are potential therapeutic targets of BSTSF in the treatment of AD.

关键词： Traditional Chinese medicine Alzheimer’s disease Endocannabinoids Hippocampus Small non-coding RNAs Transfer RNA

Statistical Entropy of the Kaluza-Klein Black Hole from the Horizon Conformal Field Theory

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Chinese Physics Letters 2001年第3期18卷 331-333页

作者： jing Ji-Liang YAN mu-Lin Institute of Physics and Department of Physics Hunan Normal UniversityChangsha 410081 Department of Astronomy and Applied Physics University of Science and Technology of ChinaHefei 230026

The statistical entropy of the Kaluza-Klein black hole is studied by counting the black hole states which form an algebra of diffeomorphism at Killing horizon with a central *** is shown that the entropy yielded by the standard Cardy formula agrees with the Bekenstein-Hawking entropy only if we take period T of function u as the periodicity of the Euclidean black *** the other hand,the first-order quantum correction to the entropy is proportional to logarithm of the Bekenstein-Hawking entropy with a factor-1/2.

关键词： horizon periodicity entropy

Effects of Curcumin on Invasion and Metastasis in the Human Cervical Cancer Cells Caski

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Chinese Journal of Cancer Research 2009年第2期21卷 159-162页

作者： Fang XU Xiaoling mu jing ZHAO Department of Emergence and ICU Department Hospital Chongqing Medical University Chongqing Medical University Chongqing 400016 of Gynecology and Obstetrics the First Affiliated 400016 Department of Pathophysiology Chongqing

Objective： To explore the effects of curcumin on invasion and metastasis in the human cervical cancer cells Caski. Methods： Caski cells were treated with 10, 25, 50tamol/L curcumin for 24, 48, 72 h. Proliferation of Caski cells was measured with MTT assay. When treated with 50pmol/L curcumin for 72 h, the expressions of MMP-2, MT1-MMP and NF-κB of cells were detected by Western-blot, and invasion and metastasis of Caski cells were evaluated with transwell chamber. Results： After being treated with 10μmol/L, 251xmol/L, 50μmol/L curcumin for 24, 48 and 72 h, the proliferation of Caski cells was inhibited in a dose-and time-dependent manner. The expression of MMP-2, MT1-MMP and NF-nB were decreased when being treated with 50μmol/L curcumin for 72 h. After treatment with 50μmol/L curcumin, in invasion assay, the number of cells in curcumin treated group to migrate to filter coated with Matrigel was reduced compared with control group（P〈0.05）. Meanwhile, in migration assay, the number of cells in curcumin treated group to migrate to filter was also decreased compared with control group （P〈0.05）. Conclusion： Curcumin could affect the invasion and metastasis of the human cervical cancer cells Caski. Inhibiting the expression of MMP-2, MT1-MMP and NF-κB was probably one of its molecular mechanisms.

关键词： Cervical cancer Curcumin Invasion Metastasis

Preparation Technology of Solvent-free Polyurethane:A Mini-Review

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Chinese Journal of Structural Chemistry 2020年第12期39卷 2057-2067,2053页

作者： SU yu-Miao WANG Ting DING yu-Lin HUANG Jia-jing LI Wen-mu Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Fujian Normal University College of Chemistiy and Material ScienceFuzhou 350007China Provincial Key Laboratory of Eco-Industrial Green Technology Wuyi University 354300China

Solvent-free polyurethanes are synthesized under certain conditions via a rapid reaction between liquid *** this process the molecular weight of the polymer is rapidly increased to produce polymeric materials containing a carbamate-based structure at a very fast *** organic solvents are completely avoided in the solvent-free polyurethane synthesis process,thus avoiding all the problems associated with the use of organic ***-free polyurethane synthetic leather is extruded directly without adding solvents in the production and processing process,which has the advantages of low VOC emission and environmentally *** review brings together theoretical and experimental research on the application and synthesis and preparation of solvent-free polyurethanes to generate an understanding of the theory and synthesis and preparation techniques associated with solvent-free *** review includes(i)the application and development direction of solvent-free polyurethane,(ii)an overview of the technology of solvent-free polyurethane synthetic leather preparation,(iii)a study of the modification and synthesis of solvent-free polyurethane prepolymers,(iv)a summary of the technology of rapid foam forming of solvent-free polyurethane and its influencing factors,(v)a review of the technology of solvent-free polyurethane synthetic leather *** addition to the review,a corresponding overview of the theoretical and experimental advances in solvent-free delayed foaming technology in recent years and a summary of the technology and experience in the preparation of solvent-free polyurethanes are also presented.

关键词： solvent-free polyurethane polyurethane synthetic leather rapid foaming molding delayed catalyst

Revisiting greenness of ionic liquids and deep eutectic solvents

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Green Chemical Engineering 2021年第2期2卷 174-186页

作者： yu Chen Tiancheng mu Department of Chemistry and Material Science Langfang Normal UniversityNO.100 Aimin West RoadAnci DistrictLangfang065000HebeiChina Department of Chemistry Renmin University of ChinaNO.59 Zhongguancun StreetHaidian DistrictBeijing100872China

Green solvents are one of the hot topics of green *** liquids(ILs)and deep eutectic solvents(DESs)are deemed as green solvents to a certain extent,and they have been applied in many areas,such as dissolution,separation,catalysis,electrochemistry and material ***,the greenness of ILs and DESs should be revisited because more and more evidences have shown that they are not always *** this perspective,besides the reported merits,the disadvantages and problems of some ILs and DESs,such as instability,volatility,hygroscopicity,toxicity,flammability,regenerability,cost,energy consumption and impurities are ***,13 strategies to avoid the disadvantages of ILs and DESs and to increase the greenness are *** of the greenness of ILs and DESs is further *** perspective provides some new viewpoints on the greenness of ILs and DESs.

关键词： Green solvents Ionic liquids Deep eutectic solvents Greenness Stability