基于距离度量的多样性图排序方法

有效结合查询相关性和多样性的扩展相关性是多样性图排序问题的一种优化目标.基于扩展相关性的多样性图排序可建模为一个子模函数优化问题,贪心子模优化算法可近似求解该问题.然而,扩展相关性不能直接度量节点间的不相似性.子模优化算法是串行算法不能充分利用诸如Spark等集群计算平台有效提高算法效率.针对这些问题,本文提出一种描述节点间不相似性的距离度量.基于此距离度量,将多样性图排序问题建模为一个在查询相关节点集上构造的带权完全图的最大和k-dispersion优化问题.提出了求解该问题的多项式时间2-近似算法.鉴于不同节点对的距离度量计算是相互独立的,进一步地提出了基于MapReduce编程模型的并行化多样性图排序算法.最后,在真实图数据集上验证了本文提出算法的高效性和有效性.     

基于UML活动图生成系统测试场景的方法

旨在研究运用统一建模语言（UML）活动图生成测试场景的方法。首先对UML活动图进行了形式化定义,确定了一系列覆盖准则。然后,根据覆盖准则制定活动图的一般处理思路,针对活动图中并发结构提出采用信号量和嵌套分割的方法进行处理。该方法有效控制了测试场景集的数量,为UML活动图的自动化测试提供了系统的、有效的、可行的方法。     

光热增强光催化性能二氧化钛(B)/玻纤布复合研究

以玻璃纤维布为基底, 以TiH₂为原料, 通过简易的化学合成及溶胶-凝胶法制备了光热增强光催化性能的二氧化钛(B)/玻璃纤维布复合材料(B-T/GFC)。通过XRD、SEM和TEM检测合成材料的成分、结构和形貌, 采用分光光度计、光学接触角测量仪、太阳光模拟器对材料的性能进行了系统研究。结果表明: 该复合材料表面形成了锐钛矿晶型的黑色TiO₂薄膜, 且晶体中存在厚度约为1 nm的无序层。同时该复合材料在250~2000 nm波长范围内具有较强的光吸收能力, 且具有强疏水性; 在 1 个太阳光强度下(1 kW/m ²), 相对于玻璃纤维布具有更强的光热能力; 其光催化降解切削废液中有机污染物(COD)的能力优于黑色TiO₂(B-T)和P25, 光照2 h的降解率约为P25的2.3倍。由此可见, B-T/GFC复合材料具有优异的光热增强光催化性能, 具有广阔的应用前景。     

Optimization and Evaluation of Magnetic Bead Separation Combined with Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectroscopy (MALDI-TOF MS) for Proteins Profiling of Peritoneal Dialysis Effluent

Peritoneal dialysis effluent (PDE) potentially carries an archive of peptides relevant to pathological processes in abdominal and surrounding tissues. Magnetic beads and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry is one such approach that offers a unique tool for profiling of peptides, but this approach has not been used in the PDE analysis. In this study, we developed a strategy for screening PDE proteins <15 kDa and applied this technique to identify potential biomarkers for peritonitis. We examined four kinds of magnetic beads, including a carbon series (C3, C8), weak cation exchange (WCX) and immobilized metal-affinity chromatography (IMAC-Cu) beads. Samples processed with IMAC-Cu magnetic beads consistently showed more MS signals across all beads within the measured mass range. Moreover, there was no difference in the number and morphology of MS signals between concentrated and unconcentrated samples. The PDE peptidome pattern, based on a panel of 15 peaks, accurately recognized peritonitis PD patients from peritonitis-free patients with sensitivity of 90.5% and specificity of 94.7% respectively. Therefore, IMAC-Cu magnetic beads and unconcentrated samples can be used as a fast and cost-effective approach for sample preparation prior to more in-depth discovery of predictive biomarkers of disease in patients on dialysis.     

A novel cell and array architecture for fet-type Ferroelectric nonvolatile memories

Abstract

A novel cell using a depletion type Metal-Ferroelectric-Semiconductor FET (MFSFET) as storage device is proposed. Its operations are based on a Metal/Ferroelectric/N-Si/P-Si (MFNP) structure. Read and write disturbance can be avoided in an array of such cells. The basic operations of device have been simulated.     

牡蛎提取物对雄性大鼠性功能的影响

目的 探究牡蛎提取物对正常雄性大鼠和半去势大鼠的性功能的影响。方法 将40只雄性SD (Sprague Dawley)大鼠随机分为4组, 各组分别灌胃受试物或纯净水, 连续灌胃30 d后进行交配试验, 并测定大鼠阴茎勃起时间。将50只雄性大鼠随机分为5组, 除正常对照组外, 其余大鼠摘除右侧睾丸, 各组分别灌胃受试物或纯净水, 连续灌胃30 d, 然后称重雄性大鼠的包皮腺、精囊腺和前列腺，测定勃起潜伏期、血清皮质醇、促黄体生成素和睾酮水平。结果 与正常对照组相比, 牡蛎提取物低、中、高剂量组均能提高大鼠的射精次数(P<0.05), 高剂量牡蛎提取物能同时提高大鼠的捕捉次数和射精率(P<0.05)。与半去势大鼠模型对照组相比, 牡蛎提取物中、高剂量组的大鼠包皮腺系数有明显增高(P<0.05), 促黄体生成素含量显著降低(P<0.01), 高剂量组大鼠的血清皮质醇含量升高(P<0.05)。结论 牡蛎提取物具有一定的雄激素样作用, 能改善大鼠性功能。     

Tuning the selectivity for ring-opening reactions of methylcyclopentane over Pt catalysts: A mechanistic study from first-principles calculations

Using density functional calculations, we studied the conversion of methylcyclopentane to its ring-opening products: branched hexanes [2-methylpentane (2MP), 3-methylpentane (3MP)], as well as unbranched n-hexane (nHx). We employed flat Pt(1 1 1) and stepped Pt(2 1 1) to describe terrace-rich large and defect-rich small Pt particles, respectively. On Pt(1 1 1), the barriers of all elementary steps for the paths leading to branched hexanes lie below 90 kJ mol^?1, while the formation of nHx features a barrier of 116 kJ mol^?1 in its C–C bond scission step. This higher barrier impedes the formation of nHx on Pt(1 1 1) and thus rationalizes the experimental observations that terrace-rich large Pt particles selectively produce branched hexanes. However, on Pt(2 1 1), the barrier of C–C scission for the formation of nHx decreases to 94 kJ mol^?1, thus implying enhanced formation of nHx over the defects, in agreement with the essentially statistical product distribution observed with defect-rich small Pt particles.     

3D-QSAR and Molecular Docking Studies on Fused Pyrazoles as p38α Mitogen-Activated Protein Kinase Inhibitors

The p38α mitogen-activated protein kinase (MAPK) has become an attractive target for the treatment of many diseases such as rheumatoid arthritis, inflammatory bowel disease and Crohn's disease. In this paper, 3D-QSAR and molecular docking studies were performed on 59 p38α MAPK inhibitors. Comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were applied to determine the structural requirements for potency in inhibiting p38α MAPK. The resulting model of CoMFA and CoMSIA exhibited good r(2) (cv) values of 0.725 and 0.609, and r(2) values of 0.961 and 0.905, respectively. Molecular docking was used to explore the binding mode between the inhibitors and p38α MAPK. We have accordingly designed a series of novel p38α MAPK inhibitors by utilizing the structure-activity relationship (SAR) results revealed in the present study, which were predicted with excellent potencies in the developed models. The results provided a useful guide to design new compounds for p38α MAPK inhibitors.     

Sapphire-bonded photonic Crystal microcavity lasers and their far-field radiation patterns

Room-temperature continuous-wave lasing was demonstrated in photonic crystal microcavities with diameters of approximately 3.2 /spl mu/m. Far-field radiation patterns of these lasers were experimentally measured and compared with numerical simulation predictions.     

复杂曲面反求工程的数据采集与处理

数据采集是反求工程技术的关键,其精度和速度直接影响模型重构的精度和效率。基于ATOS光学式三维扫描仪获取实物复杂曲面数据的方法,介绍了一套用于ATOS三维扫描的简易装置。该装置不但特别适用于体积较小的样件的扫描,而且可提高扫描精度和扫描效率,简化扫描数据的处理。文中给出了采用该装置进行实际扫描的实例。