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C2 domain of synaptotagmin I associates with lipid rafts of plasma membrane

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Chinese Science Bulletin 2008年第9期53卷 1373-1380页

作者： lu jihua HE Li SUI SenFang Department of Biological Sciences & Biotechnology State Key Laboratory of Biomembrane and Membrane Biotechnology TsinghuaUniversity Beijing 100084 China

In this paper we report that the C2 domain of synaptotagmin I (syt I) could associate with lipid rafts of plasma membrane. We demonstrate that phosphatidylinositol 4,5-bisphosphate (PIP2) in the target membrane and Ca2+ are the key factors to enhance the raft association of the C2 domain. We also found that the raft association of the C2 domain could be fulfilled by either C2A or C2B alone, suggesting that their raft association might be complementary. Finally, we indicate that destroying lipid rafts or blocking syt I-raft association could significantly reduce the Ca2+-driven release of glutamates. Our data indicate that the raft association of the C2 domain might play an important role in the regulated exocytosis.

关键词：碳晶体脂质等离子体膜薄

Effect of chemical vapor infiltration treatment on the wave-absorbing performance of carbon fiber/cement composites

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Journal of University of Science and Technology Beijing 2008年第6期15卷 808-815页

作者： Kezhi Li Chuang Wang Hejun Li Lingjun Guo jihua lu School of Materials Science Northwestern Polytechnical University Xi＇an 710072 China

Short carbon fibers were treated at high temperatures around 1100℃ through chemical vapor infiltration technology. A thinner layer ofpyrocarbon was deposited on the fiber surface. The dispersion of carbon fibers in a cement matrix and the mechanical properties of carbon fiber/cement composites were investigated by scanning electron microscopy （SEM） and other tests. The reflec- tivity of electromagnetic waves by the composites was measured in the frequency range of 8.0-18 GHz for different carbon fiber contents of 0.2wt%, 0.4wt%, 0.6wt%, and 1.0wt%. The results show that the reflectivity tends to increase with the increase of fiber content above 0.4wt%. The minimum reflectivity is -19.3 dB and the composites exhibit wave-absorbing performances. After pyrocarbon is deposited on the fiber, all the refiectivity data are far greater. They are all above -10 dB and display mainly wave-reflecting performances.

关键词： carbon fibers chemical vapor infiltration cement reflectivity wave-absorbing property

Medical Diagnosis System Based on Fast-weights Scheme

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Instrumentation 2020年第1期7卷 51-57页

作者： TIAN Shining lu jihua GU Boyu WANG Huan School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

Clinical examination data often have the features of carrying vague information,missing data and incomplete examination records,which lead to higher probabilities of misdiagnosis.A variational recursive-discriminant joint model with fast weights(FWs)scheme is ***-III data sets are trained and tested,and the results are used to *** recurrent neural network(VRNN)with FWs can better obtain the temporal features with partly missing data,and discriminant neural network(DNN)is for ***,layer regularization(LN)avoids the overflow of loss function and stabilize the dynamic parameters of each *** the simulations,10 laboratory tests were selected to predict 10 diseases,1600 samples and 400 samples were used for training and testing,*** test accuracy of disease diagnosis without FWs is 72.55%,and that with FWs is 85.80%.Simulations reveal that the FWs mechanism can effectively optimize the system model,abstracting the features for diagnose,and significantly improve the accuracy of decision-making.

关键词： Fast Weights Scheme Discriminant Neural Network Variational Recurrent Neural Network Diagnosis Accuracy

Performance of a Dual-Hop Multi-relay Cooperative Network in a Nakagami-m Fading Environment

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China Communications 2012年第4期9卷 55-62页

作者： lu jihua An Jianping Li Xiangming School of Information and Electronics Beijing Institute of TechnologyBeijing 100081P.R.China

An exact average symbol error rate analysis for the distributed dual-hop relay cooperative network with multiple relays in a Nakagami-m fading environment is *** the derivation of the moment generation function of receiver Signal-to-Noise Ratio(SNR),the sectional integral method is used,instead of the cumulative density function method which is ordinarily used by the deduction of the outage probability of S-R-D *** accurate symbol error rate of a dual-hop relay cooperative network is obtained with the closed-form Moment Genoration Function (MGF) *** correctness of the symbol error rate is verified through numerical simulations and is compared with other analytical *** deductions clearly show that the distributed cooperative diversity network presented has strong superiorities in overcoming severe fading and can achieve full diversity order.

关键词： dual-hop relay cooperative communication average symbol error rate closed-form MGF amplify-and-forward Nakagami-m fading

Optimization of fermentation medium for xylanase-producing strain Xw2

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Frontiers in Biology 2013年第6期8卷 611-617页

作者： Bingying YE Ting XUE Shichao YE Shengyan XU Weiyan LI jihua lu Fang WEI Wenjin HE Youqiang CHEN College of Life Sciences Fujian Normal University Fuzhou 350108 China Key Laboratory of Developmental and Neural Fuzhou 350108 China Key Laboratory of Sugarcane Biology and Genetic Breeding of Ministry of Agriculture Fuzhou 350108 China Environmental Protection Agency Fuzhou Sanming 350400 China

To improve the fermentation yield of xylanase by optimizing the fermentation conditions for strain Xw2, a Plackett-Burman design was used to evaluate the effects of eight variables on xylanase production by strain Xw2. The steepest ascent （descent） method was used to approach the optimal response surface experimental area. The optimal fermentation conditions were obtained by central composite design and response surface analysis. The results showed that the composition of the optimal fermentation medium was corn cob ＋ 1.5% wheat bran （1：1）, 0.04% MnSO4, 0.04% K2HPO4. 3H2O, and an inoculum size of 6% in 50 mL liquid volume （pH = 6.0）. The optimal culture conditions were 28oc at 150 r/min for 54.23 h. The results of this study can serve as the basis for the industrial production and application of xylanase.

关键词： enzyme activity fermentation Plackett-Burman test xylan

Topographic Information Based Three-Dimensional Localization Algorithm for Wireless Sensor Networks

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Topographic Information Based Three-Dimensional Localization...

2010 3rd International Conference on Computer and Electrical Engineering(ICCEE 2010)

作者： lu jihua Yao Xingmiao Li Chuan Fucai Yu School of Communication and Information Engineering University of Electronic Science and Technology of China

There have been a number of three-dimensional localization algorithms designed for wireless sensor networks, and most of them suffer from high computational complexity and error accumulation problems. In this paper, we propose Topographic Information Based Three-Dimensional Localization Algorithm (TIBTDLA) for wireless sensor networks. The basic idea is to reduce error accumulation of three-dimensional localization in wireless sensor networks by referencing topographic information. TIBTDLA exploits a limited region traversal method to locate unknown sensors. Hence, its computational complexity is reasonably low by only traversing the points in the limited region. The proposed method can be implemented in a distributed manner, and this manner gains low time complexity. We compare TIBTDLA with 3D-AML (Three Dimensional Adapted Multi-Lateration). Simulation results show that the TIBTDLA method achieves lower localization error than 3D-AML localization algorithm.

关键词： Wireless Sensor Networks three-dimensional topographic information localization

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一种用于自适应跳频系统的新型交织方法

哈尔滨工业大学学报 2013年第1期45卷 118-123页

作者：卢继华黄承飞李祥明北京理工大学信息与电子学院北京100081

提出了一种用于自适应跳频系统的新型交织方法,本方法采用素数码来控制自适应跳频系统中交织部分的信息符号变换规律,具有交织相关系数小、延时低、存储容量需求小、且实现灵活不用刻意考虑矩阵维数的特点,达到了较优的交织性能度量.Mon... 详细信息

提出了一种用于自适应跳频系统的新型交织方法,本方法采用素数码来控制自适应跳频系统中交织部分的信息符号变换规律,具有交织相关系数小、延时低、存储容量需求小、且实现灵活不用刻意考虑矩阵维数的特点,达到了较优的交织性能度量.Monte Carlo仿真结果表明,在某自适应跳频通信系统仿真平台中,本交织方法与常见的行列交织、伪随机交织方法相比,在满足特定误码率前提下,能够改善系统出现连串错误时超出纠错编码纠错能力的抗误码性能,具有实现简单、低延时及计算量小的优势,使得自适应跳频通信系统在抗干扰方面有了更好的抑制效果,其抑制干扰的效果与平方素数码相当,好于行列交织方法,仅略低于伪随机交织方法.

关键词：自适应跳频系统素数码交织交织延时与存储容量抗干扰性能

温室墙体中覆铝箔封闭空气腔热工性能模拟分析

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农业工程学报 2017年第2期33卷 227-233页

作者：张潇丹颉建明郁继华吕剑甘肃农业大学园艺学院兰州730070

通过建立封闭空气腔二维稳态流动传热模型和温室墙体一维非稳态导热模型,模拟计算封闭腔内空气温度分布,研究了日光温室墙体中覆铝箔封闭空气腔的热工性能。结果表明:壁面覆铝箔可有效减少封闭空气腔的辐射换热量;封闭空气腔的热阻随封... 详细信息

通过建立封闭空气腔二维稳态流动传热模型和温室墙体一维非稳态导热模型,模拟计算封闭腔内空气温度分布,研究了日光温室墙体中覆铝箔封闭空气腔的热工性能。结果表明:壁面覆铝箔可有效减少封闭空气腔的辐射换热量;封闭空气腔的热阻随封闭腔高度的增加而增大,高度达1.5 m后,热阻趋于不变;封闭空气腔的厚度小于0.03 m时,其热阻随厚度增加而增大,厚度超过0.03 m后,热阻逐渐减小;覆铝箔封闭空气腔高度为1.5 m、厚度为0.03 m、内外壁面温差为2~20 K时,热阻为0.70~0.55 K·m^2/W,保温隔热效果相当于0.81~0.64 m厚夯实黏土结构、0.55~0.43 m厚红砖砌体结构墙体或0.20~0.16 m厚煤渣、0.06~0.05 m厚珍珠岩、0.03~0.02 m厚聚苯板隔热材料。3组30 mm厚覆铝箔封闭空气腔加480 mm红砖复合墙体(360 mm红砖墙+3组30 mm封闭空气腔+120 mm红砖墙,240 mm红砖墙+3组30 mm封闭空气腔+240 mm红砖墙),其夜间向室内放热量较单一480 mm红砖墙体提高99.5%~104.2%,与相同结构聚苯板红砖复合墙体无明显差距。

关键词：墙体温度对流换热日光温室封闭空气腔平均导热系数热阻

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无线自组网个体移动模型分析

通信学报 2010年第2期31卷 36-43,50页

作者：刘宴涛安建平卢继华刘珩渤海大学信息科学与工程学院计算机网络智能重点实验室辽宁锦州121013 北京理工大学电子工程系北京100081

应用Palm积分分析随机点模型、随机方向模型和随机游走模型的平稳速度分布,证明速度衰减问题源于各个移动周期内速度和持续时间的相关性。应用Palm积分和几何概率分析随机点模型和随机方向模型的平稳节点分布,证明这2种模型具有非均匀... 详细信息

应用Palm积分分析随机点模型、随机方向模型和随机游走模型的平稳速度分布,证明速度衰减问题源于各个移动周期内速度和持续时间的相关性。应用Palm积分和几何概率分析随机点模型和随机方向模型的平稳节点分布,证明这2种模型具有非均匀节点分布特征。应用中心极限定理证明无边界区域随机游走模型的轨迹端点成正态分布。结果表明时间型随机游走模型是最合理的个体移动模型。

关键词：无线自组网移动模型 Palm积分几何概率速度衰减