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Ribosome-inspired electrocatalysts inducing preferential nucleation and growth of three-dimensional lithium sulfide for high-performance lithium-sulfur batteries
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作者 Zhen Wu Wenfeng He +7 位作者 Jiahui Yang Yunuo Gu Ruiqi Yang Yiran Sun Jiajia Yuan Xin Wang Junwu Zhu Yongsheng Fu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期517-526,共10页
Nucleation of lithium sulfide(Li_(2)S)induced by electrocatalysts plays a crucial role in mitigating the shut-tle effect.However,short-chain polysulfides on electrocatalysts surfaces tend to re-dissolve into elec-trol... Nucleation of lithium sulfide(Li_(2)S)induced by electrocatalysts plays a crucial role in mitigating the shut-tle effect.However,short-chain polysulfides on electrocatalysts surfaces tend to re-dissolve into elec-trolytes,delaying Li_(2)S supersaturation and its nucleation.In this study,we draw inspiration from the ribosome-driven protein synthesis process in cells to prepare ultrasmall nitrogen-doped MoS_(2) nanocrys-tals anchored on porous nitrogen-doped carbon networks(N-MoS_(2)-NC)electrocatalysts.Excitedly,the ex-situ SEM demonstrates that ribosome-inspired N-MoS_(2)-NC electrocatalysts induce early nucleation and rapid growth of three-dimensional Li_(2)s during discharge.Theoretical calculations reveal that the Li-s bond length in N-MoS_(2)-Li_(2)S(100)is shorter,and the corresponding interfacial formation energy is lower than in MoS_(2)-Li_(2)S(100).This accelerated conversion of lithium polysulfides to Li_(2)S can enhance the utilization of active substances and inhibit the shuttle effect.This study highlights the potential of ribosome-inspired N-MoS_(2)-NC in improving the electrochemical stability of Li-S batteries,providing valuable insights for future electrocatalyst design. 展开更多
关键词 Lithium-sulfur batteries ELECTROCATALYSTS Nanocrystals Ribosome-inspired Nucleation and growth
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EXPERIMENTAL INVESTIGATION AND COMPUTER SIMULATION ON DYNAMIC BUCKLING BEHAVIOR OF LIQUID-FILLED CYLINDRICAL SHELLS UNDER AXIAL IMPACT 被引量:2
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作者 Zhang, SY Lei, JP +2 位作者 Zhao, LM Cheng, GQ Lu, GY 《Acta Mechanica Solida Sinica》 SCIE EI 2000年第2期166-172,共7页
This article reports an experimental investigation on the axial impact buckling of thin metallic cylindrical shells fully filled with water. Low velocity impact tests are carried out by DHR-9401 drop hammer rig. The w... This article reports an experimental investigation on the axial impact buckling of thin metallic cylindrical shells fully filled with water. Low velocity impact tests are carried out by DHR-9401 drop hammer rig. The whole process of dynamic buckling is simulated using LS-DYNA computer code. The consistency between experimental observation and numerical simulation is quite satisfactory. The investigation indicates that quite high internal hydrodynamic pressure occurs inside the shell during the impact process. Under the combined action of the high internal pressure and axial compression plastic buckling occurs easily in the thin-walled shells and buckling modes take on regular and axisymmetric wrinkles. 展开更多
关键词 liquid-filled cylindrical shell impact buckling experimental investigation computer simulation
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Protective effects of L-arginine against ischemia-reperfusion injury in non-heart beating rat liver graft 被引量:5
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作者 Gong, Jin Lao, Xue-Jun +1 位作者 Zhang, Shui-Jun Chen, Shi 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2008年第5期481-484,共4页
BACKGROUND: Although the use of non-heart beating donors (NHBDs) could bridge the widening gap between organ demand and supply, its application to liver transplantation is limited due to the high incidence of primary ... BACKGROUND: Although the use of non-heart beating donors (NHBDs) could bridge the widening gap between organ demand and supply, its application to liver transplantation is limited due to the high incidence of primary graft loss. Prevention of liver injury in NHBDs will benefit the results of transplantation. This study was conducted to evaluate the protective effects of L-arginine on liver grafts from NHBDs. METHODS: One hundred and four Wistar rats were randomly divided into 7 groups: normal control (n=8) controls 1, 2 and 3 (C-1, C-2, C-3, n=16), and experimental 1, 2 and 3 (E-1, E-2, E-3, n=16). For groups C-1 and E-1, C-2 and E-2, and C-3 and E-3, the warm ischemia time was 0, 30, and 45 minutes, respectively. Liver grafts were flushed with and preserved in 4 degrees C Euro-collins solution containing 1 mmol/L L-arginine for 1 hour in each experimental group. Recipients of each experimental group were injected with L-arginine (10 mg/kg body weight) by tail vein 10 minutes before portal vein reperfusion. Donors and recipients of each experimental control group were treated with normal saline. Then transplantation was performed. At 1, 3, and 24 hours after portal vein reperfusion, blood samples were obtained to determine the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), nitric oxide (NO) and plasma endothelin (ET). At 3 hours after portal vein reperfusion, grafts samples were fixed in 2.5% glutaraldehyde for electron microscopic observation. RESULTS: At I hour after portal vein reperfusion, the levels of NO in groups E-1, E-2, E-3 and C-1, C-2, C-3 were lower, while the levels of plasma ET, serum ALT and AST were higher than those in the normal control group (P<0.05). At 1, 3, and 24 hours, the levels of NO in groups E-1, E-2, E-3 were higher, while the levels of plasma ET, serum ALT and AST were lower than those in the corresponding control groups (C-1, C-2, C-3) (P<0.05). The levels of NO in groups C-2 and C-3 were lower than in group C-1 (P<0.05), and the level of NO in group C-3 was lower than in group C-2 (P<0.05). At 1, 3 and 24 hours, the levels of plasma ET, serum ALT, and AST in groups E-1, E-2, E-3 were lower than those in the corresponding control groups (C-1, C-2, C-3) (P<0.05). The levels of plasma ET, serum ALT, and AST were lower in group C-3 than in groups C-1 and C-2 (P<0.05). Pathological changes in groups E-1, E-2, E-3 were milder than those in the corresponding experimental control groups (C-1, C-2, C-3). CONCLUSIONS: The imbalance between NO and ET plays an important role in the development of ischemia-reperfusion injury of liver grafts from NHBDs. L-arginine can attenuate injury in liver grafts from NHBDs by improving the balance between NO and ET. 展开更多
关键词 liver transplantation non-heart beating donor L-ARGININE nitric oxide ischemia-reperfusion injury
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Protective Effect of Schisanhenol Against Oxygen Radical Induced Mitochondrial Toxicity on Rat Heart and Liver 被引量:4
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作者 LINTONGJUN LIUGENGTAO 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1992年第1期57-64,共8页
Schisanhenol (SAL) had been shown to have potent antioxidant activities. The protective effects of SAL against oxygen radical induced mitochondrial injuries of rat heart and liver were investigated in the present stud... Schisanhenol (SAL) had been shown to have potent antioxidant activities. The protective effects of SAL against oxygen radical induced mitochondrial injuries of rat heart and liver were investigated in the present study. The ferrous-cysteine induced mitochondrial lipid peroxidation was significantly inhibited by SAL, while the loss of ATPase activity induced by the lipid peroxidation was prevented. The rigidification of mitochondrial membrane, as well as swelling, lysis and disintegration of the mitochondria induced by ferrous-cysteine were all significantly inhibited by SAL. These results further confirm that SAL possesses antioxidant activity. 展开更多
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Computer Control Techniques of Phased Array Radars
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作者 Zhang, Boyan Cai, Qingyu Lu, Jianxiong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第1期31-37,共7页
The computer control techniques applicable to electronically scanned multifunction radars are presented. The software and hardware architecture for the real time control and the data processing within a phased array ... The computer control techniques applicable to electronically scanned multifunction radars are presented. The software and hardware architecture for the real time control and the data processing within a phased array radar are described. The software system comprising a number of tasks is written in C language and implemented. The results show that the algorithm for the multitask adaptive scheduling and the multitarget data processing is suitable for multifunction phased array radars. 展开更多
关键词 Phased array radar Adaptive scheduling PRIORITY Data processing Multitarget tracking Searching and tracking.
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RISK ANALYSIS OF JACKET PLATFORMS DURING INSTALLATION ON SEA
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作者 Li, Jianchao Hu, Ruihua 《China Ocean Engineering》 SCIE EI 1990年第2期199-207,共9页
In this paper, the uncertainty of environmental loads and soil resistance is analyzed, and the wave and current loads acting on a jacket during the unpiled installation phase are converted to its foundation loads. Wit... In this paper, the uncertainty of environmental loads and soil resistance is analyzed, and the wave and current loads acting on a jacket during the unpiled installation phase are converted to its foundation loads. With a probability model of soil resistance, risk applied to the design of temporary seafloor support of a platform and the risk of failure, or probability of horizontal sliding, tilting and ovrturning can be pridicted. Thereby, optimum design and installation procedure may be chosen according to safety and economical factors. A Fortran program based on the model is developed. The application of the program to a jacket in South China Sea is described. 展开更多
关键词 ECONOMICS FOUNDATIONS Soil Structure Interaction PROBABILITY
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Study on Speciation of Pr(III) in Human Blood Plasma by Computer Simulation
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作者 Liu, YM Han, JF +4 位作者 Wu, ZJ Wang, Y Yang, KY Niu, CJ Ni, JZ 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第3期263-264,共2页
Speciation of Pr(III) in human blood plasma has been investigated by computer simulation. The speciation and distribution of Pr(III) has been obtained. It has been found that most of Pr(III) is bound to phosphate and ... Speciation of Pr(III) in human blood plasma has been investigated by computer simulation. The speciation and distribution of Pr(III) has been obtained. It has been found that most of Pr(III) is bound to phosphate and to form precipitate. The results obtained-are in accord with experimental observations. 展开更多
关键词 SPECIATION praseodymium(III) computer simulation
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Cardioprotective effects of selective Na^+/H^+ exchanger inhibitor HOE642 against ischemia/reperfusion injury in immature hearts
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作者 周荣华 《China Medical Abstracts》 2007年第2期134-135,共2页
Objective To compare the cardioprotective effect of HOE642, a highly selective Na^+/H^+ exchanger isoform-1 (NHE1) inhibitor, administered at different phase of ischemia/reperfusion in immature hearts: pre-ischem... Objective To compare the cardioprotective effect of HOE642, a highly selective Na^+/H^+ exchanger isoform-1 (NHE1) inhibitor, administered at different phase of ischemia/reperfusion in immature hearts: pre-ischemia, during ischemia and reperfusion. 展开更多
关键词 抑制作用 缺血作用 心脏病 症状
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Validation of the Chinese system for cardiac operative risk evaluation (SinoSCORE):the experience from Guangdong Cardiovascular Institute
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作者 郭惠明 《外科研究与新技术》 2011年第3期182-182,共1页
Objective To validate of the Chinese system for cardiac operative risk evaluation (SinoSCORE) in Cantonese surgery patients. Methods Data from Guangdong Cardiovascular Institute in the period January 2004 through Dece... Objective To validate of the Chinese system for cardiac operative risk evaluation (SinoSCORE) in Cantonese surgery patients. Methods Data from Guangdong Cardiovascular Institute in the period January 2004 through December 2008 were analyzed on 2462 Cantonese heart surgery patients. First,compared risk factors of this series and database of SinoSCORE,and then calculated 展开更多
关键词 SINOSCORE Validation of the Chinese system for cardiac operative risk evaluation the experience from Guangdong Cardiovascular Institute
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New Polarographic Immunoassay Using Copper Ion as Catalyst for Conversion of Substrate Instead of Natural Enzyme
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作者 Song, JF Wang, JX +1 位作者 Guo, W Zhao, MR 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第10期922-923,共2页
A new electrochemical immunoassay based on catalytic conversion of substrate by labeled metal ion and polarographic detection of generated product was developed. In this immunoassay,copper ion was used A catalyst for ... A new electrochemical immunoassay based on catalytic conversion of substrate by labeled metal ion and polarographic detection of generated product was developed. In this immunoassay,copper ion was used A catalyst for the conversion of substrate to substitute natural enzyme. Copper ion was labeled to antigens such as Human serum albumin(HSA), Diphtheria Toxoid (DT),Tetanus Toxoid (TT ) through bifunctional chelating agent diethylenetriamine pentaacetic acid (DTPA).After heterogeneous competitive immune reaction, the labeled copper ion was released by acidification, and then catalyzes chemically the conversion of substrate o-phenyldiamine (OPD ) to electroactive product 2,3-diaminophenazine (DAP). The product DAP was detected by using linearsweep polarography. The sensitivity of the proposed assay for the determination of HSA, DT and TT is superior to those of previous one based on direct detection of the labeled metal ion. 展开更多
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Prosthesis-patient mismatch in the mitral valve position:the initial result of a single-institutional observational study in China
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作者 任崇雷 《外科研究与新技术》 2011年第3期178-179,共2页
Objective To analysis the causes of valve prosthesis-patient mismatch (PPM) after mitral valve replacement in Chinese patients. Methods Consecutive 100 patients for elective mitral valve replacement from January 2009 ... Objective To analysis the causes of valve prosthesis-patient mismatch (PPM) after mitral valve replacement in Chinese patients. Methods Consecutive 100 patients for elective mitral valve replacement from January 2009 to June 2009 were enrolled and followed for this study. There were 37 males and 63 females. 展开更多
关键词 PPM Prosthesis-patient mismatch in the mitral valve position
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Heterogeneously-catalyzed aerobic oxidation of furfural to furancarboxylic acid with CuO-Promoted MnO_(2)
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作者 Xin Yu Tingke Jin +10 位作者 Huiqiang Wang Guoqing Zhang Wenlong Jia Lincai Peng Yong Sun Xing Tang Xianhai Zeng Shuliang Yang Zheng Li Feng Xu Lu Lin 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第6期1683-1692,共10页
A cost-effective and sustainable noble-metal free catalyst system based on ubiquitously available Mn-Cu bimetallic oxides was served as efficient catalysts for furfural selective oxidation to furancarboxylic acid(FA).... A cost-effective and sustainable noble-metal free catalyst system based on ubiquitously available Mn-Cu bimetallic oxides was served as efficient catalysts for furfural selective oxidation to furancarboxylic acid(FA). Interestingly, Mn_(2)Cu_(1)O_(x)exhibited an excellent furfural conversion of 99% with quantitative selectivity toward FA. Especially, we demonstrate the significant weakening of the Mn-O bonds with the incorporation of CuO into the Mn-Cu oxides, resulting in an improved OLreactivity of Mn_(2)Cu_(1)O_(x), which brings about a higher catalytic activity for furfural oxidation. More importantly, Mn_(2)Cu_(1)O_(x)could exhibit YFA>90% over 5 cycles of reusability test. Through this study, the relationship between the morphology, surface chemistry, and catalytic activity of Mn-Cu bimetallic oxides are elucidated, providing a simple and environmentally friendly catalytic strategy and scientific basis for the development of Mn-Cu bimetallic oxides bioderived molecular aerobic oxidation materials. 展开更多
关键词 FURFURAL Mn–Cu bimetallic oxides Oxidation Lattice oxygen Furancarboxylic acid
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Crysformer:An attention-based graph neural network for properties prediction of crystals
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作者 王田 陈家辉 +3 位作者 滕婧 史金钢 曾新华 Hichem Snoussi 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期15-20,共6页
We present a novel approach for the prediction of crystal material properties that is distinct from the computationally complex and expensive density functional theory(DFT)-based calculations.Instead,we utilize an att... We present a novel approach for the prediction of crystal material properties that is distinct from the computationally complex and expensive density functional theory(DFT)-based calculations.Instead,we utilize an attention-based graph neural network that yields high-accuracy predictions.Our approach employs two attention mechanisms that allow for message passing on the crystal graphs,which in turn enable the model to selectively attend to pertinent atoms and their local environments,thereby improving performance.We conduct comprehensive experiments to validate our approach,which demonstrates that our method surpasses existing methods in terms of predictive accuracy.Our results suggest that deep learning,particularly attention-based networks,holds significant promise for predicting crystal material properties,with implications for material discovery and the refined intelligent systems. 展开更多
关键词 deep learning property prediction CRYSTAL attention networks
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The Characteristics of Glued Tensile Shear Strength Constituted of Wood Cut by CO_(2) Laser
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作者 Fatemeh Rezaei Milan Gaff +10 位作者 Róbert Nemeth Jerzy Smardzewski Peter Niemz Haitao Li Anil Kumar Sethy Luigi Todaro Gourav Kamboj Sumanta Das Roberto Corleto Gianluca Ditommaso Miklós Bak 《Journal of Renewable Materials》 EI 2023年第8期3277-3296,共20页
The performance of engineered wood products is highly associated with proper bonding and an efficient cutting method.This paper investigates the influence of CO_(2) laser cutting on the wetting properties,the modified ch... The performance of engineered wood products is highly associated with proper bonding and an efficient cutting method.This paper investigates the influence of CO_(2) laser cutting on the wetting properties,the modified che-mical component of the laser-cut surface,and the strength and adhesive penetration near the bondline.Beech-wood is cut by the laser with varying processing parameters,cutting speeds,gas pressures,and focal point positions.The laser-cut samples were divided into two groups,sanded and non-sanded samples.Polyvinyl acetate adhesive(PVAc)was used to bond the groups of laser-cut samples.After assembly with cold pressing,the tensile shear test was carried out.Numerical modelling was carried out to determine the partial elongation and shear strain of the glue line.Based on this,the shear modulus and linear elasticity of the glue line were estimated.Scan-ning electron microscopy was used to assess the adhesive penetration into the porosity structure of the laser-cut samples,and the depth of the heat-affected zone.The laser-cut surface was analysed by Fourier transform infrared spectroscopy.The wetting properties of the laser-cut surface were investigated by using a contact angle goni-ometer.The numerical model of the strain-stress curve confirmed the experimental model.The highest modulus of the linear elasticity of the glue in the numerical calculation belongs to the joint containing laser-cut samples at a gas pressure of 21(bar).The penetration depth of PVAc adhesive into the porosity structure of the laser-cut sam-ples was similar to that of sawn samples.The deepest heat-affected zone in the laser-cut samples was 150µm.A PVAc drop disappeared immediately on the laser-cut surface without sanding,but gradually on the sanded surface.In contrast,the drop on the sawn surface remained with an angle of 32°–48°.The degradation of hemi-cellulose and lignin was proven by the lower intensity of the C=O and C-O Bonds,compared to the sawn surface. 展开更多
关键词 CO_(2)laser cutting speed focal point position gas pressure glued tensile shear strength
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Structural Isomers:Small Change with Big Difference in Anion Storage 被引量:1
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作者 Huichao Dai Yuan Chen +7 位作者 Yueyue Cao Manli Fu Linnan Guan Guoqun Zhang Lei Gong Mi Tang Kun Fan Chengliang Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期222-234,共13页
Organic electrode materials are promising for batteries.However,the reported organic electrodes are often facing the challenges of low specific capacity,low voltage,poor rate capability and vague charge storage mechan... Organic electrode materials are promising for batteries.However,the reported organic electrodes are often facing the challenges of low specific capacity,low voltage,poor rate capability and vague charge storage mechanisms,etc.Isomers are good platform to investigate the charge storage mechanisms and enhance the performance of batteries,which,however,have not been focused in batteries.Herein,two isomers are reported for batteries.As a result,the isomer tetrathiafulvalene(TTF)could store two monovalent anions reversibly,deriving an average discharge voltage of 1.05 V and a specific capacity of 220 mAh g−1 at a current density of 2 C.On the other hand,the other isomer tetrathianaphthalene could only reversibly store one monovalent anion and upon further oxidation,it would undergo an irreversible solid-state molecular rearrangement to TTF.The molecular rearrangement was confirmed by electrochemical performances,X-ray diffraction patterns,nuclear magnetic resonance spectra,and 1H detected heteronuclear multiple bond correlation spectra.These results suggested the small structural change could lead to a big difference in anion storage,and we hope this work will stimulate more attention to the structural design for boosting the performance of organic batteries. 展开更多
关键词 Zinc-organic batteries ISOMERS Solid-state molecular rearrangement Anion storage P-type organic electrode materials
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Joint alignment and steering to manage interference
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作者 Zhao Li Xiujuan Liang +2 位作者 Yinghou Liu Jia Liu Zheng Yan 《Digital Communications and Networks》 SCIE CSCD 2024年第2期429-438,共10页
In wireless communication networks,mobile users in overlapping areas may experience severe interference,therefore,designing effective Interference Management(IM)methods is crucial to improving network performance.Howe... In wireless communication networks,mobile users in overlapping areas may experience severe interference,therefore,designing effective Interference Management(IM)methods is crucial to improving network performance.However,when managing multiple disturbances from the same source,it may not be feasible to use existing IM methods such as Interference Alignment(IA)and Interference Steering(IS)exclusively.It is because with IA,the aligned interference becomes indistinguishable at its desired Receiver(Rx)under the cost constraint of Degrees-of-Freedom(DoF),while with IS,more transmit power will be consumed in the direct and repeated application of IS to each interference.To remedy these deficiencies,Interference Alignment Steering(IAS)is proposed by incorporating IA and IS and exploiting their advantages in IM.With IAS,the interfering Transmitter(Tx)first aligns one interference incurred by the transmission of one data stream to a one-dimensional subspace orthogonal to the desired transmission at the interfered Rx,and then the remaining interferences are treated as a whole and steered to the same subspace as the aligned interference.Moreover,two improved versions of IAS,i.e.,IAS with Full Adjustment at the Interfering Tx(IAS-FAIT)and Interference Steering and Alignment(ISA),are presented.The former considers the influence of IA on the interfering user-pair's performance.The orthogonality between the desired signals at the interfered Rx can be maintained by adjusting the spatial characteristics of all interferences and the aligned interference components,thus ensuring the Spectral Efficiency(SE)of the interfering communication pairs.Under ISA,the power cost for IS at the interfered Tx is minimized,hence improving SE performance of the interfered communication-pairs.Since the proposed methods are realized at the interfering and interfered Txs cooperatively,the expenses of IM are shared by both communication-pairs.Our in-depth simulation results show that joint use of IA and IS can effectively manage multiple disturbances from the same source and improve the system's SE. 展开更多
关键词 INTERFERENCE Interference management Interference alignment Interference steering Spectral efficiency
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短暂性脱髓鞘导致长期认知障碍、髓鞘改变和神经网络同步缺陷
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作者 Océane Mercier Pascale P Quilichini +7 位作者 Karine Magalon Florian Gil Antoine Ghestem Fabrice Richard Thomas Boudier Myriam Cayre Pascale Durbec 杜一星(编译) 《神经损伤与功能重建》 2024年第3期F0003-F0003,共1页
在成年大脑中,活动依赖性髓鞘可塑性是正确学习和记忆巩固所必需的。因此,髓鞘的丢失、改变,甚至细微的结构变更都会损害神经网络活动,导致功能障碍。在多发性硬化症中,虽然自发的髓鞘修复过程是可能的,但患者之间存在异质性。髓鞘修复... 在成年大脑中,活动依赖性髓鞘可塑性是正确学习和记忆巩固所必需的。因此,髓鞘的丢失、改变,甚至细微的结构变更都会损害神经网络活动,导致功能障碍。在多发性硬化症中,虽然自发的髓鞘修复过程是可能的,但患者之间存在异质性。髓鞘修复有时会导致功能恢复,这通常在运动水平比在认知水平更明显。在铜宗处理的小鼠模型中,大量脑脱髓鞘随后发生自发且强烈的髓鞘再生。然而,重组髓鞘虽然具有功能,但可能不会表现出与发育髓鞘相同的形态特征,这可能会对神经网络的活动产生影响。基于此,本研究使用铜腙处理的小鼠模型来分析短暂性脱髓鞘对脑结构、功能和认知的长期影响。本研究结果表明,尽管脱鞘事件后存在髓鞘再生,但仍会导致长期认知障碍,例如空间工作记忆、社交记忆、认知灵活性和多动症的缺陷。这些缺陷与内侧前额叶皮质(m PFC)和海马体(HPC)髓鞘含量的减少以及结构髓鞘修饰有关,表明这些结构中的髓鞘再生过程可能不完善。在体电生理记录表明,脱髓鞘事件改变了HPC-mPFC活动的同步性,这对于记忆过程至关重要。总而言之,本研究数据表明,短暂脱髓鞘后的髓鞘修复过程不允许完全恢复皮质结构中的初始髓鞘特性。这些细微的变更改变了神经网络特征并导致小鼠长期认知缺陷。 展开更多
关键词 认知 多发性硬化症小鼠模型 髓鞘再生 神经网络活动
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Study of the mechanisms of acupuncture and moxibustion treatmentfor ulcerative colitis ratsinview of the gene expression of cytokines 被引量:45
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作者 Wu HG Zhou LB +4 位作者 Pan YY Huang C Chen HP Shi Z Hua XG 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第6期515-517,共3页
AIM:To observe the effect of acupuncture and moxibustion on the expression of IL-1beta and IL-6 mRNA in ulcerative colitis rats.METHODS:The SD rat ulcerative colitis model was created by immunological method associate... AIM:To observe the effect of acupuncture and moxibustion on the expression of IL-1beta and IL-6 mRNA in ulcerative colitis rats.METHODS:The SD rat ulcerative colitis model was created by immunological method associated with local stimulation. Colonic mucosa was prepared from human fresh surgical colonic specimens, homogenized by adding appropriate amount of normal saline and centrifuged at 3000r/min. The supernatant was collected for measurement of protein conentration and then mixed with Freund adjuvant. This antigen fluid was first injected into the plantae of the model group rats, and then into their plantae, dorsa, inguina and abdominal cavities (noFreund adjuvant for the last injection) again on the 10th, 17th, 24th and 31st day. When a certain titer of serum anti colonic antibody was reached, 2% formalin and antigen fluid (no Freund adjuvant) were administered separately by enema. The ulcerative colitis rat model was thus set up. The animals were randomly divided into four groups: model control group (MC, n = 8), electro acupuncture group (EA, n = 8), herbs partition moxibustion group (HPM 8), normal control group (NC,n = 8). HPM: Moxa cones made of refined mugwort floss were placed on the medicinal pad (medicinal pad dispensing: Radix Aconiti praeparata, cortex Cinnamomi, etc) for Qihai (RN 6) and Tianshu (ST 25, bilateral) and ignited. Two moxa cones were used for each acupoint once a day and 14 times in all. EA: Tianshu (bilateral) and Qihai were stimulated by the intermittent pulse with 2Hz frequency, 4mA intensity for 20 minutes once a day and 14 times in all. After treatment, rats of all four groups were killed simultaneously. The spleen was separated and the distal colon was dissected. Total tissue RNA was isolated by the guanidinium thiocyanate phenol chloroform extraction method. RT-PCR technique was used to study the expression of IL-1 beta and IL-6 mRNA.RESULTS:IL-1 beta and IL-6 mRNAs were not detected in the spleen and colonic mucosa of the NC rats, whereas they were significantly expressed in that of the MC rats.IL-1 beta and IL-6 mRNAs were markedly lower in the EA and HPM rats than that in MC rats. There was no significant difference between the levels of IL-1 beta and IL-6 mRNAs in the EA and HPM rats. The expressions of IL-1 beta and IL-6 mRNAs were nearly the same in the spleen and colon of all groups.CONCLUSION:Acupuncture and moxibustion greatly inhibited the expression of IL-1 beta and IL-6 mRNA in the experimental ulcerative colitis rats. 展开更多
关键词 colitis ulcerative/therapy acupuncture and moxibustion therapy gene expression CYTOKINES interleukin-1 beta interleukin-6
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Distribution of available soil water capacity in China 被引量:59
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作者 ZHOUWenzuo LIUGaohuan +1 位作者 PANJianjun FENGXianfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期3-12,共10页
The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for m... The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for most of soil profiles and the nationwide ASWC largely remains lacking in relevant soil data in China. This work was to estimate ASWC based on physical and chemical properties and analyze the spatial distribution of ASWC in China. The pedo-transfer functions (PTFs), derived from 220 survey data of ASWC, and the empirical data of ASWC based on soil texture were applied to quantify the ASWC. GIS technology was used to develop a spatial file of ASWC in China and the spatial distribution of ASWC was also analyzed. The results showed the value of ASWC ranges from 15 × 10-2 cm3·cm-3 to 22 × 10-2 cm3·cm-3 for most soil types, and few soil types are lower than 15 × 10-2 cm3·cm-3 or higher than 22 × 10-2 cm3·cm-3. The ASWC is different according to the complex soil types and their distribution. It is higher in the east than that in the west, and the values reduce from south to north except the northeastern part of China. The "high" values of ASWC appear in southeast, northeastern mountain regions and Northeast China Plain. The relatively "high" values of ASWC appear in Sichuan basin, Huang-Huai-Hai plain and the east of Inner Mongolia. The relatively "low" values are distributed in the west and the Loess Plateau of China. The "very low" value regions are the northern Tibetan Plateau and the desertified areas in northern China. In some regions, the ASWC changes according to the complex topography and different types of soils. Though there remains precision limitation, the spatial data of ASWC derived from this study are improved on current data files of soil water retention properties for Chinese soils. This study presents basic data and analysis methods for estimation and evaluation of ASWC in China. 展开更多
关键词 available soil water capacity pedo-transfer functions China
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Learning algorithm and application of quantum BP neural networks based on universal quantum gates 被引量:26
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作者 Li Panchi Li Shiyong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期167-174,共8页
A quantum BP neural networks model with learning algorithm is proposed. First, based on the universality of single qubit rotation gate and two-qubit controlled-NOT gate, a quantum neuron model is constructed, which is... A quantum BP neural networks model with learning algorithm is proposed. First, based on the universality of single qubit rotation gate and two-qubit controlled-NOT gate, a quantum neuron model is constructed, which is composed of input, phase rotation, aggregation, reversal rotation and output. In this model, the input is described by qubits, and the output is given by the probability of the state in which (1) is observed. The phase rotation and the reversal rotation are performed by the universal quantum gates. Secondly, the quantum BP neural networks model is constructed, in which the output layer and the hide layer are quantum neurons. With the application of the gradient descent algorithm, a learning algorithm of the model is proposed, and the continuity of the model is proved. It is shown that this model and algorithm are superior to the conventional BP networks in three aspects: convergence speed, convergence rate and robustness, by two application examples of pattern recognition and function approximation. 展开更多
关键词 quantum computing universal quantum gate quantum neuron quantum neural networks
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