Kinetic freeze-out temperatures in central and peripheral collisions:which one is larger?

The kinetic freeze-out temperatures, T_0, in nucleus–nucleus collisions at the Relativistic Heavy Ion Collider(RHIC) and Large Hadron Collider(LHC) energies are extracted by four methods:(1) the Blast-Wave model with Boltzmann–Gibbs statistics(the BGBW model),(2) the Blast-Wave model with Tsallis statistics(the TBW model),(3) the Tsallis distribution with flow effect(the improved Tsallis distribution), and(4) the intercept in T=T_0+ am_0(the alternative method), where m_0 denotes the rest mass and T denotes the effective temperature which can be obtained by different distribution functions. It is found that the relative sizes of T_0 in central and peripheral collisions obtained by the conventional BGBW model which uses a zero or nearly zero transverse flow velocity, β_T, are contradictory in tendency with other methods. With a re-examination for β_Tin the first method,in which β_Tis taken to be ～ (0:40 ± 0:07)c, a recalculation presents a consistent result with others. Finally, our results show that the kinetic freeze-out temperature in central collisions is larger than that in peripheral collisions.     

CUDA-TP:基于GPU的自顶向下完整蛋白质鉴定并行算法

蛋白质及蛋白质翻译后修饰(post-translational modifications, PTMs)的鉴定是蛋白质组学研究的基础,对整个领域的进一步发展有着十分重要的意义.近年来,质谱设备的快速发展使得获取“自顶向下”(top-down,TD)的高精度完整蛋白质质谱数据成为可能.目前基于TD质谱数据的完整蛋白质鉴定算法虽然在匹配精度、PTM位点的推断上取得了一些成效,但它们运行时间还有很大的不足和提升空间.利用图形处理器(graphics processing unit, GPU)可以将大规模的重复计算并行化,提高串行程序的执行速度.CUDA-TP算法基于通用并行计算架构(compute unified device architecture, CUDA)来计算蛋白质与TD质谱数据的匹配分数.首先,对每一个质谱数据,CUDA-TP利用优化的MS-Filter算法在蛋白质数据库中过滤出其对应的少数候选蛋白质集合,然后通过AVL(adelson-velskii and landis)树加速质谱匹配过程.GPU中的多线程技术被用来并行化谱图网格及最终数组中所有元素的前驱结点的求解.同时,该算法还使用target-decoy策略来控制蛋白质与质谱图匹配结果的错误发现率(false discovery rate, FDR).实验结果表明：CUDA-TP算法能够有效地加速完整蛋白质的鉴定,速度分别比MS-TopDown和MS-Align+快10倍与2倍.到目前为止,这是唯一能够利用CUDA架构来加速完整蛋白质鉴定的研究工作.CUDA-TP源代码公布在https://github.com/dqiong/CUDA-TP.     

Characterization of GaN grown on 4H-SiC and sapphire by Raman spectroscopy and high resolution XRD

and electron mobility in GaN grown on sapphire and 4H-SiC are analyzed.     

JW787型井温仪的研制与应用

JW87型井温仪是山东省煤田地质局测井组为适应目前煤田地质勘探钻孔中的地温测量工作而研制的一种半导体热敏电阻测温仪器.     

Room-temperature continuous-wave operation of GaN-based blue-violet laser diodes with a lifetime longer than 1000 h

GaN-based continuous-wave operated blue-violet laser diodes (LDs) with long lifetime are demonstrated, which are grown on a c-plane GaN substrate by metal organic chemical vapor deposition with a 10 × 600 μm² ridge waveguide structure. The electrical and optical characteristics of a blue-violet LD are investigated under direct-current injection at room temperature (25 °C). The stimulated emission wavelength and peak optical power of the LD are around 413 nm and over 600 mW, respectively. In addition, the threshold current density and voltage are as small as 1.46 kA/cm² and 4.1 V, respectively. Moreover, the lifetime is longer than 1000 hours under room-temperature continuous-wave operation.     

Inclusion Capture Probability Prediction Model for Bubble Floatation in Turbulent Steel Flow

Metallurgical and Materials Transactions B - The turbulent flow around bubbles is simulated for the fixed turbulent kinetic energy. Inclusion motion through the flow field is studied by considering...     

Nanobridged rhombic antennas supporting both dipolar and high-order plasmonic modes with spatially superimposed hotspots in the mid-infrared

Mid-infrared antennas (MIRAs) support highly-efficient optical resonance in the infrared, enabling multiple applications, such as surface-enhanced infrared abso...     

Glucose Metabolism,Neural Cell Senescence and Alzheimer’s Disease

Alzheimer’s disease (AD), an elderly neurodegenerative disorder with a high incidence and progressive memory decline, is one of the most expensive, lethal, and burdening diseases. To date, the pathogenesis of AD has not been fully illustrated. Emerging studies have revealed that cellular senescence and abnormal glucose metabolism in the brain are the early hallmarks of AD. Moreover, cellular senescence and glucose metabolism disturbance in the brain of AD patients may precede amyloid-β deposition or Tau protein phosphorylation. Thus, metabolic reprogramming targeting senescent microglia and astrocytes may be a novel strategy for AD intervention and treatment. Here, we recapitulate the relationships between neural cell senescence and abnormal glucose metabolism (e.g., insulin signaling, glucose and lactate metabolism) in AD. We then discuss the potential perspective of metabolic reprogramming towards an AD intervention, providing a theoretical basis for the further exploration of the pathogenesis of and therapeutic approach toward AD.     

Plasmon-enhanced nanosoldering of silver nanoparticles for high-conductive nanowires electrodes

The silver nanowires (Ag NWs) electrodes, which consist of incompact Ag nanoparticles (NPs) formed by multi-photon photoreduction, usually have poor conductivit...     

Formation of hierarchical Si3N4 foams by protein-based gelcasting and chemical vapor infiltration

Silicon nitride foams with a hierarchical porous structure was formed by the combination of protein-based gelcasting,chemical vapor infiltration,and in-situ growth of silicon nitride nanowires.The porosity of the foams can be controlled at 76.3-83.8 vol%with an open porosity of 70.2—82.8 vol%.The pore size distribution was presented in three levels:<2μm(voids among grains and cross overlapping of silicon nitride nanowires(SNNWs)),10—50μm(cell windows),and>100μm(cells).The resulted compressive strength of the porous bodies at room temperature can achieve up to 18.0±1.0 MPa(porosity=76.3 vol%)while the corresponding retention rate at 800℃was 58.3%.Gas permeability value was measured to be 5.16(cm³·cm)/(cm²·s·kPa).The good strength,high permeability together with the pore structure in multiple scales enabled the foam materials for microparticle infiltration applications.