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Hypothalamic paraventricular nucleus stimulation reduces intestinal injury in rats with ulcerative colitis

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World Journal of Gastroenterology 2016年第14期22卷 3769-3776页

作者： Quan-Jun Deng Ding-jing Deng jin che Hai-Rong Zhao Jun-Jie Yu Yong-Yu Lu Department of Neurosurgery General Hospital Affiliated to Tianjin Medical University Department of Gastroenterology General Hospital Affiliated to Tianjin Medical University Department of Cerebral surgery people's Hospital of Haimen

AIM: To investigate the effect and mechanism of stimulation of the hypothalamic paraventricular nucleus with glutamate acid in rats with ulcerative colitis(UC).METHODS: The rats were anesthetized with 10% chloral hydrate via abdominal injection and treated with an equal volume of TNBS + 50% ethanol enema, injected into the upper section of the anus with the tail facing up. Colonic damage scores were calculated after injecting a certain dose of glutamic acid into the paraventricular nucleus(p VN), and the effect of the nucleus tractus solitarius(NTS) and vagus nerve in alleviating UC injury through chemical stimulation of the p VN was observed in rats. Expression changes of C-myc, Apaf-1, caspase-3, interleukin(IL)-6, and IL-17 during the protection against UC injury through chemical stimulation of the p VN in rats were detected by Western blot. Malondialdehyde(MDA) content and superoxide dismutase(SOD) activity in colon tissues of rats were measured by colorimetric methods. RESULTS: chemical stimulation of the PVN significantly reduced UC in rats in a dose-dependent manner. The protective effects of the chemical stimulationof the p VN on rats with UC were eliminated after chemical damage to the p VN. After glutamate receptor antagonist kynurenic acid was injected into the p VN, the protective effects of the chemical stimulation of the p VN were eliminated in rats with UC. After AVpVl receptor antagonist([Deamino-penl, val4, D-Arg8]-vasopressin) was injected into NTS or bilateral chemical damage to NTS, the protective effect of the chemical stimulation of p VN on UC was also eliminated. After chemical stimulation of the p VN, SOD activity increased, MDA content decreased, C-myc protein expression significantly increased, caspase-3 and Apaf-1 protein expression significantly decreased, and IL-6 and IL-17 expression decreased in colon tissues in rats with UC. CONCLUSION: chemical stimulation of the hypothalamic p VN provides a protective effect against UC injury in rat

关键词： Paraventricular nucleus Nucleus tractus solitarius Ulcerative colitis Arginine vasopressin 2 4 6-trinitrobenzene sulfonic acid

a-Si/c-Si heterojunction solar cells on SiSiC ceramic substrates

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Rare Metals 2006年第z1期25卷 186-189页

作者： LI Xudong XU Ying che Xiaoqi Beijing Solar Energy Research Institute Beijing 100083 China Beijing Solar Energy Research Institute Beijing 100083 China Beijing Solar Energy Research Institute Beijing 100083 China

Silicon thin-film solar cells are considered to be one of the most promising cells in the future for their potential advantages, such as low cost, high efficiency, great stability, simple processing, and none-pollution. In this paper, latest progress on poly-crystalline silicon solar cells on ceramic substrates achieved by our group was reported. Rapid thermal chemical vapor deposition (RTCVD) was used to deposited poly-crystalline silicon thin films, and the grains of as-grown film were enlarged by Zone-melting Recrystallization (ZMR). As a great change in cell′s structure, traditional diffused pn homojunction was replaced by a-Si/c-Si heterojunction, which lead is to distinct improvement in cell′s efficiency. A conversion efficiency of 3.42% has been achieved on 1 cm2 a-Si/c-Si heterojunction solar cell (Isc=16.93 mA, Voc=310.9 mV, FF=0.6493, AM=1.5 G, 24 ℃), while the cell with diffused homojunction only got an efficiency of 0.6%. It indicates that a-Si emitter formed at low temperature might be more suitable for thin film cell on ceramics.

关键词： a-Si/c-Si heterojunction thin film solar cell ceramic substrate

Integrating the ecosystem service in sustainable plateau spatial planning:A case study of the Yarlung Zangbo River Basin

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Journal of Geographical Sciences 2021年第2期31卷 281-297页

作者： che Lei ZHOU Liang XU Jiangang School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China

The Yarlung Zangbo River Basin(YZRB)is a key ecological protection area on the Qinghai-Tibet Plateau(QTP).Determination of the ecosystem service values(ESVs)can help recognize the benefits of sustainable *** is gradually becoming the main path that constructs plateau spatial planning of integrating ecological protection,and achieves global sustainable development goals(SDGs)in *** this paper,the spatio-temporal dynamic evolutions of the ESVs were estimated on the multiple scales of“basin,subbasin and watershed”from 1980 to *** main factors influencing ESVs were explored in terms of physical geography,human activities,and climate *** had been proposed that sustainable spatial planning including ecological protection,basin management,and regional development was urgent to set *** results show that the increase in wetland and forest and results in an increase of 9.4%in the *** should be paid to the reduction of water and *** conservation(WC),waste treatment(WT),and soil formation and conservation(SFC)are the most important ecosystem services in the *** present,the primary problem is to solve the ESVs decreasing caused by glacier melting,grassland degradation,and desertification in the upper reaches *** middle reaches should raise the level of supply *** services should be increased in the lower reaches region on the premise of protecting *** ESVs in adjacent watersheds are interrelated and the phenomenon of“high agglomeration and low agglomeration”is obvious,existing hot-spots and cold-spots of ***,when the altitude is 4500-5500 m,the temperature is 3-8°C,and the annual precipitation is 350-650 mm,ESVs could reach its maximum.A framework of sustainable plateau spatial planning could provide references to delimit the ecological protection red line,key ecological function zone,and natural resource asset accounting on the QTP.

关键词： ecosystem service values spatial planning ecological protection Yarlung Zangbo River Basin Qinghai-Tibet Plateau

Exploring the efficiency of image metric for assessing the visual quality of 3D mesh model

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International Journal of Modeling, Simulation, and Scientific Computing 2018年第6期9卷 147-170页

作者： Li che Fengju Kang College of Marine Engineering Northwestern Polytechnical University Xi’an 710072 P.R.China National Key Laboratory of Underwater Information Process and Control Xi’an 710072 P.R.China

Recent developments in 3D graphics technology have led to extensive processes on 3D meshes(e.g.,compression,simplification,transmission and watermarking),these processes unavoidably cause the visual perceptual degradation of the 3D *** existing mesh visual quality evaluation metrics either require topology constrain or fail to reflect the perceived visual ***,for the 3D objects that are observed on 2D screens by the users,it is reasonable to apply image metric to assess the distortion caused by mesh *** attempt to explore the efficiency of image metric for assessing the visual fidelity of the simplified 3D model in this *** this purpose,several latest and most effective image metrics,2D snapshots,number and pooling algorithms are involved in our study,and finally tested on the IEETA simplification *** statistical data allow the researcher to select the optimal parameter for this image-based mesh visual quality assessment and provide a new perspective for the design and performance assessment of mesh simplification algorithms.

关键词： Image metric 3D model visual quality assessment mesh distortion correlation analysis,performance analysis.

Faster-than-Nyquist signaling based on filter bank multicarrier modulation with joint optimization

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Journal of Systems Engineering and Electronics 2022年第6期33卷 1208-1223页

作者： che Hui PENG Dingxiang GUO Fachang BAI Yong School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Ruijie Networks Co. LtdFuzhou 350002China School of Information and Communication Engineering Hainan UniversityHaikou 570228China

Multi-carrier faster-than-Nyquist(MFTN)can improve the spectrum efficiency(SE).In this paper,we first analyze the benefit of time frequency packing MFTN(TFP-MFTN).Then,we propose an efficient digital implementation for TFP-MFTN based on filter bank multicarrier *** time frequency packing ratio pair in our proposed implementation scheme is optimized with the SE ***,the joint optimization for the coded modulation MFTN based on extrinsic information transfer(EXIT)chart is *** Monte-Carlo simulations are carried out to verify performance gain of the joint inner and outer code *** results demonstrate that the TFPMFTN has a 0.8 dB and 0.9 dB gain comparing to time packing MFTN(TP-MFTN)and higher order Nyquist at same SE,respectively;the TFP-MFTN with optimized low density parity check(LDPC)code has a 2.9 dB gain comparing to that with digital video broadcasting(DVB)*** with previous work on TFP-MFTN(SE=1.55 bit/s/Hz),the SE of our work is improved by 29%and our work has a 4.1 dB gain at BER=1×10^(-5).

关键词： faster-than-Nyquist filter bank multi-carrier time-frequency packing(TFP) spectrum efficiency(SE) joint optimization

Numerical investigation of transient gas–solid heat transfer in a packed bed:Impact of intra-particle thermal diffusion

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Particuology 2024年第7期90卷 404-411页

作者： Hanqiao che Yuanhe Yue Zhaohua Jiang Duan Li School of Mechanical Engineering Guangxi UniversityNanningGuangxi530004China School of chemical Engineering University of BirminghamBirminghamB152TTUK Hebei Engineering Research Center of Advanced Energy Storage Technology and Equipment School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China Hebei Key Laboratory of Thermal Science and Energy Clean Utilization School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China School of Mechatronics and Vehicle Engineering Chongqing Jiaotong UniversityChongqing400074China School of Instrumentation and Opto-Electronic Engineering Beihang UniversityBeijing 100191China

The transient heat transfer behaviours in a packed bed have been studied using coupled computational fluid dynamics(CFD)and discrete element method(DEM).Intra-particle thermal diffusion,which is a crucial but rarely explored issue,is considered by introducing a one-dimensional diffusion equation in the DEM *** achieve a sufficiently long physical time of simulations,we further reduce the computational cost by applying periodic boundary condition to a small segment of the packed *** study demonstrates a shifting peak heat flow rate from the bottom to the top of the packed bed during the initial warming *** affirm that the influence of thermal diffusion within a particle is noteworthy only for particles exhibiting a high Biot number(e.g.,Bi=1.2).This insight enriches our understanding of heat transfer mechanisms in packed beds and their practical engineering applications.

关键词： Packed bed Intra-particle heat transfer CFD–DEM

Hierarchical Magnetic Network Constructed by CoFe Nanoparticles Suspended Within “Tubes on Rods” Matrix Toward Enhanced Microwave Absorption

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Nano-Micro Letters 2021年第3期13卷 80-94页

作者： Chunyang Xu Lei Wang Xiao Li Xiang Qian Zhengchen Wu Wenbin You Ke Pei Gang Qin Qingwen Zeng Ziqi Yang chen jin Renchao che Laboratory of Advanced Materials Department of Materials Science and Collaborative Innovation Center of Chemistry for Energy Materials(iChem)Fudan UniversityShanghai 200438People’s Republic of China

Hierarchical magnetic-dielectric composites are promising functional materials with prospective applications in microwave absorption(MA)***,a three-dimension hierarchical“nanotubes on microrods,”core–shell magnetic metal–carbon composite is rationally constructed for the first time via a fast metal–organic frameworksbased ligand exchange strategy followed by a carbonization treatment with *** magnetic CoFe nanoparticles are embedded within one-dimensional graphitized carbon/carbon nanotubes supported on micro-scale Mo2N rod(Mo2N@CoFe@C/CNT),constructing a special multi-dimension hierarchical MA *** exchange reaction is found to determine the formation of hierarchical magnetic-dielectric composite,which is assembled by dielectric Mo2N as core and spatially dispersed CoFe nanoparticles within C/CNTs as ***2N@CoFe@C/CNT composites exhibit superior MA performance with maximum reflection loss of−53.5 dB at 2 mm thickness and show a broad effective absorption bandwidth of 5.0 *** Mo2N@CoFe@C/CNT composites hold the following advantages:(1)hierarchical core–shell structure offers plentiful of heterojunction interfaces and triggers interfacial polarization,(2)unique electronic migration/hop paths in the graphitized C/CNTs and Mo2N rod facilitate conductive loss,(3)highly dispersed magnetic CoFe nanoparticles within“tubes on rods”matrix build multi-scale magnetic coupling network and reinforce magnetic response capability,confirmed by the off-axis electron holography.

关键词： Hierarchical core-shell MOF-based composites CoFe nanoparticles Magnetic network Microwave absorption

Effects of Biochar Application on Soil Organic Carbon in Degraded Saline-sodic Wetlands of Songnen Plain,Northeast China

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Chinese Geographical Science 2021年第5期31卷 877-887页

作者： che Qianjin LI Min ZHANG Zhongsheng 无 Yancheng Tearchers School Yancheng 224002China North Jiangsu Institute of Agricultural and Rural Modernization Yancheng 224002China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130012China Xinfeng Middle School Yancheng 224100China

Biochar amendment is considered as an efficient practice for improving carbon storage in ***,to what extent that biochar application promotes organic carbon in saline-sodic soils remains poorly *** comparing soil organic carbon(SOC)contents change before and after biochar addition,we deciphered the driving factors or processes that control SOC change in response to biochar application.A limited increase in SOC was observed,about by 1.16%-12.80%,even when biochar was applied at the rate of 10%of bulk soil *** application enhanced soil dissolved organic carbon(DOC)significantly by up to 67%.It was estimated that about 50%SOC was allocated to small macroaggregates(250-2000μm,CPOC),and SOC in silt and clay-sized particles(<53μm)decreased obviously after biochar *** biomass increased with biochar amendment,of which actinomycetes(ACT),fungus(FUN),protozoon(PRO),and bacteria with straight-chain saturated fatty acids(OB)increased *** linear regression models implied that DOC was governed by ACT and soil N∶P ratio,while SOC mostly depended on *** principal component analysis and the partial least square path model(PLS-PM)indicated that biochar addition aggravated nitrogen limitation in saline-sodic soils,and effects of microorganisms on regulating SOC greatly depended on nitrogen *** application had vastly changed interactions between environmental factors and SOC in saline-sodic *** of nutrients on SOC shifted to great inhibition from strong stimulation after biochar addition,meanwhile,aggregation was the only factor presenting positive effects on *** to eliminate nutrient limitation and better soil aggregation process should be considered in priority when biochar was used to improve SOC in saline-sodic soils.

关键词： biochar saline-sodic soil soil organic carbon phospholipid fatty acid nutrient Songnen Plain China

A novel compound data classification method and its application in fault diagnosis of rolling bearings

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International Journal of Intelligent Computing and Cybernetics 2017年第1期10卷 80-90页

作者： Anxin Sun Ying che College of Optical and Electronic Information Changchun University of Science and TechnologyChangchunChina

Purpose-The purpose of this paper is to provide a fault diagnosis method for rolling *** bearings are widely used in industrial appliances,and their fault diagnosis is of great importance and has drawn more and more *** on the common failure mechanism of failure modes of rolling bearings,this paper proposes a novel compound data classification method based on the discrete wavelet transform and the support vector machine(SVM)and applies it in the fault diagnosis of rolling ***/methodology/approach-Vibration signal contains large quantity of information of bearing status and this paper uses various types of wavelet base functions to perform discrete wavelet transform of vibration and *** vectors are constructed based on several time-domain indices of the denoised *** is then used to perform classification and fault *** the optimal wavelet base function is determined based on the diagnosis ***-Experiments of fault diagnosis of rolling bearings are carried out and wavelet functions in several wavelet families were *** results show that the SVM classifier with the db4 wavelet base function in the db wavelet family has the best fault diagnosis ***/value-This method provides a practical candidate for the fault diagnosis of rolling bearings in the industrial applications.

关键词： Support vector machine Fault diagnosis Data classification Discrete wavelet transform Rolling bearing