目的甘丙肽受体1(galanin receptor 1,GALR1)信号通路在痛觉调节中发挥重要作用,该研究利用坐骨神经慢性压迫(chronic constriction injury of the sciatic nerve,CCI)大鼠模型,探索慢病毒介导的DREAM沉默治疗在CCI模型大鼠疼痛中的作...目的甘丙肽受体1(galanin receptor 1,GALR1)信号通路在痛觉调节中发挥重要作用,该研究利用坐骨神经慢性压迫(chronic constriction injury of the sciatic nerve,CCI)大鼠模型,探索慢病毒介导的DREAM沉默治疗在CCI模型大鼠疼痛中的作用及其对GALR1的表达调控。方法选择健康雄性SD大鼠24只,随机分为4组(n=6):即RNA干扰组、空白载体组、单纯CCI组和正常对照组。鞘内置管前后分别测定基础痛阈,RNA干扰组和空白载体组于CCI后经微导管给予pKCSHR-Puro/GFP-DREAM慢病毒和空白载体,并测定腰段脊髓内下游调控元件拮抗分子(downstream regulatory element antagonist,DREAM)和GALR1的蛋白表达。结果大鼠痛阈的变化:手术同侧热痛阈和机械痛阈测定结果表明,CCI处理后,RNA干扰组、空白载体组及单纯CCI组在各个时间点热痛阈和机械痛阈较正常对照组均显著降低(P<0.01);RNA干扰组鞘内注射后较注射前痛阈显著升高,治疗后相同时间点RNA干扰组较空白载体组及单纯CCI组痛阈亦显著升高。Western blotting结果表明,与其他实验组对比,RNA干扰组的DREAM蛋白表达水平显著下调,而GALR1蛋白表达水平较空白载体组、单纯CCI组亦有显著下调。结论 DREAM可以调控GALR1的表达,提示甘丙肽受体1信号通路参与DREAM基因调节大鼠神经病理性疼痛。展开更多
For reducing the inter-user interference in multi-user multiple-input multiple-output（MU-MIMO） wireless communication systems,e.g.,MIMO-orthogonal frequency division multiplexing（MIMO-OFDM） systems,it is often des...For reducing the inter-user interference in multi-user multiple-input multiple-output（MU-MIMO） wireless communication systems,e.g.,MIMO-orthogonal frequency division multiplexing（MIMO-OFDM） systems,it is often desirable to the complex preprocessing at the transmitter.This paper proposes a multi-user beamforming algorithm with sub-codebook selection.Based on the minimal leakage criterion,the codebook selection,limited feed-forward and minimum mean square error（MMSE） detection are combined in the proposed algorithm.This avoids the complex channel matrix decomposition and inversion.Consequently,the computational complexity at the transmitter is significantly reduced.Simulation results show that the proposed algorithm performs better than existing beamforming algorithms.展开更多
Wise arrangement of antennas is critical in wireless cellular systems for both reductions of co-channel interference (CCI) and increase the quality of service (QoS). In this paper, a novel architecture for antenna arr...Wise arrangement of antennas is critical in wireless cellular systems for both reductions of co-channel interference (CCI) and increase the quality of service (QoS). In this paper, a novel architecture for antenna arrangement in CDMA wireless cellular systems is presented. In this architecture that we called Microzone, every cell is divided into three (or more) zones and information transmission in downlink channel is done by an antenna which is placed at the outer region of the related zone. Also, the transmitting signal by the mobile station (MS) in uplink channel is received by all the antennas of the related cell. Analytical calculations of the received signal to noise ratio (SIR) and outage probability for both microzone and used architectures show that proposed architecture has better performance in compared with the used architecture. Also, simulation results confirm lower outage probability in uplink channel for microzone architecture.展开更多
With the development of manufacture technology, the multi-level cell(MLC)technique dramatically increases the storage density of NAND flash memory. As the result,cell-to-cell interference(CCI) becomes more serious and...With the development of manufacture technology, the multi-level cell(MLC)technique dramatically increases the storage density of NAND flash memory. As the result,cell-to-cell interference(CCI) becomes more serious and hence causes an increase in the raw bit error rate of data stored in the cells.Recently, low-density parity-check(LDPC)codes have appeared to be a promising solution to combat the interference of MLC NAND flash memory. However, the decoding complexity of the sum-product algorithm(SPA) is extremely high. In this paper, to improve the accuracy of the log likelihood ratio(LLR) information of each bit in each NAND flash memory cell, we adopt a non-uniform detection(N-UD) which uses the average maximum mutual information to determine the value of the soft-decision reference voltages.Furthermore, with an aim to reduce the decoding complexity and improve the decoding performance, we propose a modified soft reliabilitybased iterative majority-logic decoding(MSRBI-MLGD) algorithm, which uses a non-uniform quantizer based on power function to decode LDPC codes. Simulation results show that our design can offer a desirable trade-off between the performance and complexity for high-column-weight LDPC-coded MLC NAND flash memory.展开更多
针对协同分布式的天线传输(CDAT)技术在使用频分多址(FDMA)时,不可避免地造成干扰的过载,致使发射信号峰均比(Peak-to-average signal power ratio,PAPR)增加的问题,从理论上提出了一种多载波系统中下行链路的结合MMSE和空间分集联合接...针对协同分布式的天线传输(CDAT)技术在使用频分多址(FDMA)时,不可避免地造成干扰的过载,致使发射信号峰均比(Peak-to-average signal power ratio,PAPR)增加的问题,从理论上提出了一种多载波系统中下行链路的结合MMSE和空间分集联合接收方法。首先,在相邻宏单元共道干扰的情况下,描述了用于空间分集的空时分组编码传输分集(STBCTD),以及用于多用户空间复用的最小均方误差滤波和奇异值分解(MMSE-SVD)。然后,为了抑制CDAT作用下PAPR的增大,由同频干扰(CCI)分布着手,引入了不需要无线终端信息传输的盲选择映射(Blind SLM),同时给出了STBC、CCI、SINR及BER的详细数学表达。蒙特-卡洛的仿真结果表明:在相同误码率BER条件下,相比于传统方式,本文算法对系统的信噪比性能可以提高1 dB左右。该方案在充分考虑了同频干扰CCI后,CDAT算法可以更为有效地提高系统容量,其也为研究无线蜂窝多接入系统下行链路的性能提供了一种新的思路。展开更多
To minimize transmitting power,an adaptive resource allocation algorithm is proposed for multi-user multiple input multiple output-orthogonal frequency division multiplexing(MIMO-OFDM)downlink with correlated channels...To minimize transmitting power,an adaptive resource allocation algorithm is proposed for multi-user multiple input multiple output-orthogonal frequency division multiplexing(MIMO-OFDM)downlink with correlated channels,which,based on the user’s grouping according to their spatial correlations,combines the shared manner and the exclusive manner to allocate sub-carriers.Between different groups the shared manner with a null steering method based on group marginal users is applied,whereas within a group the exclusive manner is applied.The simulations show that the power efficiency and spectral efficiency are improved;the base station transmitting antenna number and the computational complexity is decreased.展开更多
文摘目的甘丙肽受体1(galanin receptor 1,GALR1)信号通路在痛觉调节中发挥重要作用,该研究利用坐骨神经慢性压迫(chronic constriction injury of the sciatic nerve,CCI)大鼠模型,探索慢病毒介导的DREAM沉默治疗在CCI模型大鼠疼痛中的作用及其对GALR1的表达调控。方法选择健康雄性SD大鼠24只,随机分为4组(n=6):即RNA干扰组、空白载体组、单纯CCI组和正常对照组。鞘内置管前后分别测定基础痛阈,RNA干扰组和空白载体组于CCI后经微导管给予pKCSHR-Puro/GFP-DREAM慢病毒和空白载体,并测定腰段脊髓内下游调控元件拮抗分子(downstream regulatory element antagonist,DREAM)和GALR1的蛋白表达。结果大鼠痛阈的变化:手术同侧热痛阈和机械痛阈测定结果表明,CCI处理后,RNA干扰组、空白载体组及单纯CCI组在各个时间点热痛阈和机械痛阈较正常对照组均显著降低(P<0.01);RNA干扰组鞘内注射后较注射前痛阈显著升高,治疗后相同时间点RNA干扰组较空白载体组及单纯CCI组痛阈亦显著升高。Western blotting结果表明,与其他实验组对比,RNA干扰组的DREAM蛋白表达水平显著下调,而GALR1蛋白表达水平较空白载体组、单纯CCI组亦有显著下调。结论 DREAM可以调控GALR1的表达,提示甘丙肽受体1信号通路参与DREAM基因调节大鼠神经病理性疼痛。
基金support by the National Natural Science Foundation of China (60702060)the 111 Project
文摘For reducing the inter-user interference in multi-user multiple-input multiple-output（MU-MIMO） wireless communication systems,e.g.,MIMO-orthogonal frequency division multiplexing（MIMO-OFDM） systems,it is often desirable to the complex preprocessing at the transmitter.This paper proposes a multi-user beamforming algorithm with sub-codebook selection.Based on the minimal leakage criterion,the codebook selection,limited feed-forward and minimum mean square error（MMSE） detection are combined in the proposed algorithm.This avoids the complex channel matrix decomposition and inversion.Consequently,the computational complexity at the transmitter is significantly reduced.Simulation results show that the proposed algorithm performs better than existing beamforming algorithms.
文摘Wise arrangement of antennas is critical in wireless cellular systems for both reductions of co-channel interference (CCI) and increase the quality of service (QoS). In this paper, a novel architecture for antenna arrangement in CDMA wireless cellular systems is presented. In this architecture that we called Microzone, every cell is divided into three (or more) zones and information transmission in downlink channel is done by an antenna which is placed at the outer region of the related zone. Also, the transmitting signal by the mobile station (MS) in uplink channel is received by all the antennas of the related cell. Analytical calculations of the received signal to noise ratio (SIR) and outage probability for both microzone and used architectures show that proposed architecture has better performance in compared with the used architecture. Also, simulation results confirm lower outage probability in uplink channel for microzone architecture.
基金supported in part by the NSF of China (61471131, 61771149, 61501126)NSF of Guangdong Province 2016A030310337+1 种基金the open research fund of National Mobile Communications Research Laboratory, Southeast University (No. 2018D02)the Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme (2017-ZJ022)
文摘With the development of manufacture technology, the multi-level cell(MLC)technique dramatically increases the storage density of NAND flash memory. As the result,cell-to-cell interference(CCI) becomes more serious and hence causes an increase in the raw bit error rate of data stored in the cells.Recently, low-density parity-check(LDPC)codes have appeared to be a promising solution to combat the interference of MLC NAND flash memory. However, the decoding complexity of the sum-product algorithm(SPA) is extremely high. In this paper, to improve the accuracy of the log likelihood ratio(LLR) information of each bit in each NAND flash memory cell, we adopt a non-uniform detection(N-UD) which uses the average maximum mutual information to determine the value of the soft-decision reference voltages.Furthermore, with an aim to reduce the decoding complexity and improve the decoding performance, we propose a modified soft reliabilitybased iterative majority-logic decoding(MSRBI-MLGD) algorithm, which uses a non-uniform quantizer based on power function to decode LDPC codes. Simulation results show that our design can offer a desirable trade-off between the performance and complexity for high-column-weight LDPC-coded MLC NAND flash memory.
文摘针对协同分布式的天线传输(CDAT)技术在使用频分多址(FDMA)时,不可避免地造成干扰的过载,致使发射信号峰均比(Peak-to-average signal power ratio,PAPR)增加的问题,从理论上提出了一种多载波系统中下行链路的结合MMSE和空间分集联合接收方法。首先,在相邻宏单元共道干扰的情况下,描述了用于空间分集的空时分组编码传输分集(STBCTD),以及用于多用户空间复用的最小均方误差滤波和奇异值分解(MMSE-SVD)。然后,为了抑制CDAT作用下PAPR的增大,由同频干扰(CCI)分布着手,引入了不需要无线终端信息传输的盲选择映射(Blind SLM),同时给出了STBC、CCI、SINR及BER的详细数学表达。蒙特-卡洛的仿真结果表明:在相同误码率BER条件下,相比于传统方式,本文算法对系统的信噪比性能可以提高1 dB左右。该方案在充分考虑了同频干扰CCI后,CDAT算法可以更为有效地提高系统容量,其也为研究无线蜂窝多接入系统下行链路的性能提供了一种新的思路。
基金supported by the National Natural Science Foundation of China (Grant No.60572039).
文摘To minimize transmitting power,an adaptive resource allocation algorithm is proposed for multi-user multiple input multiple output-orthogonal frequency division multiplexing(MIMO-OFDM)downlink with correlated channels,which,based on the user’s grouping according to their spatial correlations,combines the shared manner and the exclusive manner to allocate sub-carriers.Between different groups the shared manner with a null steering method based on group marginal users is applied,whereas within a group the exclusive manner is applied.The simulations show that the power efficiency and spectral efficiency are improved;the base station transmitting antenna number and the computational complexity is decreased.
