淫羊藿基于CCNB1诱导免疫细胞浸润在膀胱癌中的作用及机制研究

目的:探究淫羊藿治疗膀胱癌的关键活性成分及其作用机制。方法:利用中药系统药理学数据库与分析平台筛选淫羊藿的药物活性成分及靶点,使用R语言筛选GSE13507和GSE37815的差异基因,将药物与差异基因取交集后,运用TCGA和GEO数据库中的临床信息分析和验证药物疾病靶点与膀胱癌预后的关系。运用UALCAN数据库分析CCNB1的表达与膀胱癌临床及病理资料的相关性。最后,运用TIMER分析膀胱癌中CCNB1的表达与免疫细胞浸润及患者预后的关系。结果:共筛选出17个淫羊藿的有效成分和11个药物疾病靶点。靶点最多点的活性成分为槲皮素、木犀草素和山柰酚,活性成分作用最多的靶点为GSK3B和CCNB1。GSK3B与膀胱癌患者总生存期无关。CCNB1高表达于膀胱癌组织中,且与膀胱癌患者预后呈负相关。CCNB1表达与CD8+T细胞浸润呈正相关,CD8+T细胞浸润水平越高患者预后越差。结论:CCNB1是淫羊藿的主要作用靶点,淫羊藿可通过靶向CCNB1调节CD8+T细胞浸润,从而影响膀胱癌患者预后。

25-羟基胆固醇对大鼠关节软骨细胞的影响及其机制

目的探讨25-羟基胆固醇对大鼠软骨细胞基质合成及降解相关基因表达的影响及其机制。方法原代大鼠关节软骨细胞分为对照组(正常细胞不做处理)、模型组[白介素-1β(IL-1β)进行骨关节炎(OA)造模]和5、25、125μmol/L组(分别给予5、25、125μmol/L的25-羟基胆固醇处理)。检测5组软骨细胞总胆固醇(TCH)含量、Ⅱ型胶原前体α1(Col2a1)、蛋白聚糖(Aggrecan)、基质金属蛋白酶-13(MMP-13)、肝脏X受体α(LXRα)、ATP结合盒转运蛋白A1(ABCA1)和ABCG1的mRNA表达情况。结果模型组软骨细胞Col2a1、Aggrecan和LXRα的mRNA表达低于对照组,而MMP-13的mRNA表达高于对照组(P<0.05)。125μmol/L组Col2a1、Aggrecan、LXRα、ABCA1和ABCG1的mRNA表达水平低于模型组,但MMP-13的mRNA表达升高(P<0.05)。125μmol/L组软骨细胞TCH含量较对照组显著增加(P<0.05)。结论胆固醇可能通过抑制软骨细胞胆固醇流出通路,进而导致软骨细胞内胆固醇蓄积,最终引起软骨细胞质量降低,加重OA发展进程。

RLS channel estimation with adaptive forgetting factor in space-time coded MIMO-OFDM systems

Considering that channel estimation plays a crucial role in coherent detection, this paper addresses a method of Recursive-least-squares (RLS) channel estimation with adaptive forgetting factor in wireless space-time coded multiple-input and multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems. Because there are three different forgetting factor scenarios including adaptive, two-step and conventional ones applied to RLS channel estimation, this paper describes the principle of RLS channel estimation and analyzes the impact of different forgetting factor scenarios on the performances of RLS channel estimation. Simulation results proved that the RLS algorithm with adaptive forgetting factor (RLS-A) outperformed that with two-step forgetting factor (RLS-T) or with conventional forgetting factor (RLS-C) in both estimation accuracy and robustness over the multiple-input multiple-output (MIMO) channel, i.e., a wide-sense stationary uncorrelated scattering (WSSUS) and frequency-selective slowly fading channel. Hence, we can employ the RLS-A method by adjusting forgetting factor adaptively to track and estimate channel state parameters successfully in space-time coded MIMO-OFDM systems.

A high performance frequency offset estimator for OFDM

This paper proposes a simple method to enlarge the estimation range of conventional carrier frequency offset (CFO) estimation methods based on correlations among the identical parts of the preamble. A novel preamble is designed, which is composed of one regular OFDM training block with even numbers of identical parts and one irregular OFDM training block with odd numbers of identical parts. The initial estimates obtained over the two training blocks are next exploited to jointly estimate the CFO. By elaborately selecting the numbers of identical parts for the two training blocks, the proposed CFO estimator can estimate frequency offset over tens of the subcarrier spacing. Simulation results showed that the proposed CFO estimator satisfies the estimate range requirement for the practical OFDM systems, while achieving a very good estimate performance.

基于时空大数据技术的“三线一单”智能研判平台在环评审查中的应用

编制实施“三线一单”是国家生态环境管理制度的创新,是解决重大生态环境问题的有效手段。开展“三线一单”编制成果智能化应用对生态环境日常监管、规划及环评审查等工作有着重要意义。重庆市在全国率先完成“三线一单”编制,并在此基础上搭建了“三线一单”智能研判平台。主要阐述了利用时空大数据空间分析、空间叠加分析、数据挖掘等技术,建成一套实现“三线一单”成果数据的集中管理、聚合展示、数据共享以及智能研判的“三线一单”智能研判平台。通过平台建设,推动“三线一单”管理体系的建立,为战略和规划环评、优化生态环境空间规划、重大项目落地等提供智能化支撑,助力营商环境优化,促进节约资源和保护环境的生产生活方式的形成。

A novel cell search scheme for OFDM cellular systems

A novel cell search scheme for OFDM cellular systems is proposed. It is based on one OFDM symbol with several identical slots as preamble, the time domain repetition structure of which can be utilized to accomplish OFDM timing/frequency synchronization. The cell ID is comprised of two parts: a sub-carrier mask index g and a sequence index x. Each sub-carrier mask activates or deactivates some of the sub-carriers, after which a differentially coded sequence is loaded on pairs of the adjacent active sub-carriers. The user equipment (UE) recognizes the mask with index g via power detection of the received frequency domain signal. Then it estimates the index x from differential demodulation followed by detection of the frequency domain se-quence. In order to improve the performance, a method of jointly estimating g and x is devised. Simulation results showed that the proposed scheme is able to support a very large number of cell IDs while maintaining a good performance even in bad multi-cell environment.

A novel MMSE based codebook construction for MIMO precoded spatial multiplexing with limited feedback

This paper deals with the design and performance analysis of the transmission precoder optimization for multiple-input multiple-output (MIMO) systems with limited feedback of channel state information (CSI). We assume that the receiver can get perfect channel knowledge by channel estimation while the transmitter only has partial channel knowledge from limited feedback. We present a minimum mean square error (MMSE) criterion based codebook construction algorithm for MIMO pre- coded spatial multiplexing systems under a specific average power constraint. The optimal transmitter structure is employed in this paper. Simulation results show that the MMSE criteria based codebook construction algorithm with hybrid design of power allocation and precoding can achieve better performance than that of equal power allocation based codebook of previous research.