BioStarM-140s芯片基因信息查询系统的构建及应用

应用生物信息学数据库查询的方法,对B ioS tarM-140s小鼠基因表达芯片上的14 112个基因进行相应注释信息的查询和所对应蛋白质功能的分类.首先参照人类综合型芯片上基因的功能分类,设定了14个蛋白质类别,然后采用V isual C 编程语言,构建了基因信息查询系统.应用该查询系统,进行了网络生物学数据库信息资源的自动直接查询,共搜索到有注释信息的基因12 070个;进一步按照所设定的14个蛋白质类别对12 070个基因进行分类查询,搜索到了与这14个分类相符合的、具有详细蛋白质功能注释信息的基因共1 606个.     

高压浓相煤粉气力输送差压信号多分辨分析

为了探究高压浓相气力输送过程中时频空间的内部特征,利用六尺度多分辨小波分析对试验差压信号进行时频分解.引进能量、Shannon熵和标准差STD作为特征量对气固两相流频域空间进行分析.分析表明:浓相气力输送过程中,差压信号中的能量主要分布在低频区,Shannon熵从高频到低频上呈先减小后增大分布趋势.在相同的试验压力条件下,随着表观速度的增大,低频所占据的能量份额减小,信号脉动向高频移动;高频d1和d2的Shannon熵和a6上的STD增大,低频d4~d6上的Shannon熵和d1~d6上的STD减小.为进一步研究流型辨识及流动稳定性提供了新方法.     

基于群偏好与用户偏好协同演化的群推荐方法

群推荐系统已经成为社交网络平台的重要工具,为群体用户提供兼顾个性化和整体满意度的产品和服务.现有群推荐方法大多是对个性化推荐方法的集成和聚合,忽略了群体和用户的交互影响以及群偏好和成员偏好的动态变化,从而无法保障群推荐系统的效果.为此,本文提出一种基于群偏好和用户偏好协同演化的群推荐方法,能够建模群体和用户的动态交互.具体而言,本文将用户偏好建模成其历史偏好和群影响的加权聚合结果,将群偏好建模成群历史偏好和新加入成员偏好的加权聚合结果,最终预测群体可能消费的产品列表和成员可能加入的群体列表.实验结果表明,本文所提模型在群体消费行为和用户加群行为的预测表现都优于基准算法,并兼具很好的鲁棒性.     

基于时间窗的SVDBN近似推理算法研究

变结构动态贝叶斯网络(SVDBN)在处理非稳态过程的不确定问题具有其独特的优越性。为克服SVDBN推理算法不能实现在线推理的缺陷,在引入SVDBN的时间窗和时间窗宽度概念基础上,阐述了基于时间窗的SVDBN在线近似推理机制,提出了2种在线近似推理算法,即基于时间窗的变结构离散动态贝叶斯网络(SVDDBN)递推推理算法和基于时间窗的SVDDBN快速推理算法。通过仿真实验验证了这2种算法的有效性,并从复杂度、适用范围及更新时间等方面进行了比较。     

Forecasting stock volatility in the presence of extreme shocks: Short-term and long-term effects

This paper introduces a novel generalized autoregressive conditional heteroskedasticity–mixed data sampling–extreme shocks (GARCH-MIDAS-ES) model for stock volatility to examine whether the importance of extreme shocks changes in different time ranges. Based on different combinations of the short- and long-term effects caused by extreme events, we extend the standard GARCH-MIDAS model to characterize the different responses of the stock market for short- and long-term horizons, separately or in combination. The unique timespan of nearly 100 years of the Dow Jones Industrial Average (DJIA) daily returns allows us to understand the stock market volatility under extreme shocks from a historical perspective. The in-sample empirical results clearly show that the DJIA stock volatility is best fitted to the GARCH-MIDAS-SLES model by including the short- and long-term impacts of extreme shocks for all forecasting horizons. The out-of-sample results and robustness tests emphasize the significance of decomposing the effect of extreme shocks into short- and long-term effects to improve the accuracy of the DJIA volatility forecasts.     

基于共识粒子群的全局优化求解方法

针对粒子群优化(PSO, particle swarm optimization)和高效全局优化(EGO, efficient global optimization)两种算法的特点,提出一种共识粒子群和局部代理模型协同的全局黑箱优化算法(CPSO-LSM, consensus particle swarm optimization and local surrogate model)。该算法固定PSO算法周期对粒子进行分群并在粒子达成共识后停止,将每群粒子周围的优质子区域输出作为代理模型的建模区域,通过比较各区域最优值获得高质量最优解甚至全局最优解。不仅避免了PSO冗长的计算过程、提高了建立代理模型的速度和精度还可以避免陷入局部最优。通过对比其他算法在标准测试函数的仿真结果,CPSO-LSM具有较好的收敛速度和求解精度。     

某大跨度变截面连续箱梁桥时程分析

基于通用有限元程序软件对某桥进行了时程分析,并把理论分析计算结果与实测值进行比较分析,分析结果有助于了解该桥的结构受力性能。     

Blockage of the NLRP3 inflammasome by MCC950 improves anti-tumor immune responses in head and neck squamous cell carcinoma

The NLRP3 inflammasome is a critical innate immune pathway responsible for producing active interleukin (IL)-1β, which is associated with tumor development and immunity. However, the mechanisms regulating the inflammatory microenvironment, tumorigenesis and tumor immunity are unclear. Herein, we show that the NLRP3 inflammasome was over-expressed in human HNSCC tissues and that the IL-1β concentration was increased in the peripheral blood of HNSCC patients. Additionally, elevated NLRP3 inflammasome levels were detected in tumor tissues of Tgfbr1/Pten 2cKO HNSCC mice, and elevated IL-1β levels were detected in the peripheral blood serum, spleen, draining lymph nodes and tumor tissues. Blocking NLRP3 inflammasome activation using MCC950 remarkably reduced IL-1β production in an HNSCC mouse model and reduced the numbers of myeloid-derived suppressor cells (MDSCs), regulatory T cells (Tregs) and tumor-associated macrophages (TAMs). Moreover, inhibiting NLRP3 inflammasome activation increased the numbers of CD4⁺ and CD8⁺ T cells in HNSCC mice. Notably, the numbers of exhausted PD-1⁺ and Tim3⁺ T cells were significantly reduced. A human HNSCC tissue microarray showed that NLRP3 inflammasome expression was correlated with the expression of CD8 and CD4, the Treg marker Foxp3, the MDSC markers CD11b and CD33, and the TAM markers CD68 and CD163, PD-1 and Tim3. Overall, our results demonstrate that the NLRP3 inflammasome/IL-1β pathway promotes tumorigenesis in HNSCC and inactivation of this pathway delays tumor growth, accompanied by decreased immunosuppressive cell accumulation and an increased number of effector T cells. Thus, inhibition of the tumor microenvironment through the NLRP3 inflammasome/IL-1β pathway may provide a novel approach for HNSCC therapy.     

Genome-wide association studies of 14 agronomic traits in rice landraces

Uncovering the genetic basis of agronomic traits in crop landraces that have adapted to various agro-climatic conditions is important to world food security. Here we have identified ～ 3.6 million SNPs by sequencing 517 rice landraces and constructed a high-density haplotype map of the rice genome using a novel data-imputation method. We performed genome-wide association studies (GWAS) for 14 agronomic traits in the population of Oryza sativa indica subspecies. The loci identified through GWAS explained ～ 36% of the phenotypic variance, on average. The peak signals at six loci were tied closely to previously identified genes. This study provides a fundamental resource for rice genetics research and breeding, and demonstrates that an approach integrating second-generation genome sequencing and GWAS can be used as a powerful complementary strategy to classical biparental cross-mapping for dissecting complex traits in rice.     

Nesprin interchain associations control nuclear size

Nesprins-1/-2/-3/-4 are nuclear envelope proteins, which connect nuclei to the cytoskeleton. The largest nesprin-1/-2 isoforms (termed giant) tether F-actin through their N-terminal actin binding domain (ABD). Nesprin-3, however, lacks an ABD and associates instead to plectin, which binds intermediate filaments. Nesprins are integrated into the outer nuclear membrane via their C-terminal KASH-domain. Here, we show that nesprin-1/-2 ABDs physically and functionally interact with nesprin-3. Thus, both ends of nesprin-1/-2 giant are integrated at the nuclear surface: via the C-terminal KASH-domain and the N-terminal ABD-nesprin-3 association. Interestingly, nesprin-2 ABD or KASH-domain overexpression leads to increased nuclear areas. Conversely, nesprin-2 mini (contains the ABD and KASH-domain but lacks the massive nesprin-2 giant rod segment) expression yields smaller nuclei. Nuclear shrinkage is further enhanced upon nesprin-3 co-expression or microfilament depolymerization. Our findings suggest that multivariate intermolecular nesprin interactions with the cytoskeleton form a lattice-like filamentous network covering the outer nuclear membrane, which determines nuclear size.