Atomic-Scale Sources and Mechanism of Nanoscale Electronic Disorder in Bi2Sr2CaCu2O8+delta

The randomness of dopant atom distributions in cuprate high-critical temperature superconductors has long been suspected to cause nanoscale electronic disorder. In the superconductor Bi2Sr2CaCu2O8+delta, we identified populations of atomic-scale impurity states whose spatial densities follow closely those of the oxygen dopant atoms. We found that the impurity-state locations are strongly correlated with all manifestations of the nanoscale electronic disorder. This disorder occurs via an unanticipated mechanism exhibiting high-energy spectral weight shifts, with associated strong superconducting coherence peak suppression but very weak scattering of low-energy quasi-particles.     

Apolipoprotein E: cholesterol transport protein with expanding role in cell biology

Apolipoprotein E is a plasma protein that serves as a ligand for low density lipoprotein receptors and, through its interaction with these receptors, participates in the transport of cholesterol and other lipids among various cells of the body. A mutant form of apolipoprotein E that is defective in binding to low density lipoprotein receptors is associated with familial type III hyperlipoproteinemia, a genetic disorder characterized by elevated plasma cholesterol levels and accelerated coronary artery disease. Apolipoprotein E is synthesized in various organs, including liver, brain, spleen, and kidney, and is present in high concentrations in interstitial fluid, where it appears to participate in cholesterol redistribution from cells with excess cholesterol to those requiring cholesterol. Apolipo-protein E also appears to be involved in the repair response to tissue injury; for example, markedly increased amounts of apolipoprotein E are found at sites of peripheral nerve injury and regeneration. Other functions of apolipoprotein E, unrelated to lipid transport, are becoming known, including immunoregulation and modulation of cell growth and differentiation.     

Ultrafast flash thermal conductance of molecular chains

At the level of individual molecules, familiar concepts of heat transport no longer apply. When large amounts of heat are transported through a molecule, a crucial process in molecular electronic devices, energy is carried by discrete molecular vibrational excitations. We studied heat transport through self-assembled monolayers of long-chain hydrocarbon molecules anchored to a gold substrate by ultrafast heating of the gold with a femtosecond laser pulse. When the heat reached the methyl groups at the chain ends, a nonlinear coherent vibrational spectroscopy technique detected the resulting thermally induced disorder. The flow of heat into the chains was limited by the interface conductance. The leading edge of the heat burst traveled ballistically along the chains at a velocity of 1 kilometer per second. The molecular conductance per chain was 50 picowatts per kelvin.     

Defective sialic acid egress from isolated fibroblast lysosomes of patients with Salla disease

Normal fibroblasts exposed to N-acetylmannosamine yielded lysosome-rich granular fractions loaded with free (unbound) sialic acid, whose velocity of egress increased with increasing initial loading. Fibroblast granular fractions of patients with Salla disease exhibited negligible egress of sialic acid, whether endogenous or derived from N-acetylmannosamine exposure. Salla disease represents the first disorder demonstrated to be caused by defective transport of a monosaccharide out of cellular lysosomes.     

Comparison of the performance of traditional advection-dispersion equation and mobile-immobile model for simulating solute transport in heterogeneous soils

The traditional advection-dispersion equation (ADE) and the mobile-immobile model (MIM) are widely used to describe solute transport in heterogeneous porous media. However, the fitness of the two models is case-dependent. In this paper, the transport of conservative, adsorbing and degradable solutes through a 1 m heterogeneous soil column under steady flow condition was simulated by ADE and MIM, and sensitivity analysis was conducted. Results show that MIM tends to prolong the breakthrough process and decrease peak concentration for all three solutes, and tailing and skewness are more pronounced with increasing dispersivity. Breakthrough curves of the adsorbing solute simulated by MIM are less sensitive to the retardation factor compared with the results simulated by ADE. The breakthrough curves of degradable solute obtained by MIM and ADE nearly overlap with a high degradation rate coefficient, indicating that MIM and ADE perform similarly for simulating degradable solute transport when biochemical degradation prevails over the mass exchange between mobile and immobile zones. The results suggest that the physical significance of dispersivity should be carefully considered when MIM is applied to simulate the degradable solute transport and/or ADE is applied to simulate the adsorbing solute transport in highly dispersive soils.     

激光辐照绵羊精液对精子磷代谢效应的研究

研究表明，低剂量的氦氖激光可以提高精子的活力和精子对３２Ｐｉ的摄入量，它们两者之间存在有强的正相关关系。说明精子受激光照射后，３２Ｐｉ摄入量的提高对精子的功能状态有重要意义。     

CFRP加固钢筋混凝土梁的非线性有限元仿真分析

为研究碳纤维增强复合材料(CFRP)加固钢筋混凝土梁的工作性能,利用大型有限元分析软件ANSYS,分别对钢筋混凝土梁、CFRP与钢筋混凝土梁之间的粘结性能以及CFRP单元进行有限元模拟;结合算例仿真分析了加固前后钢筋混凝土梁的承载力性能,初步探讨了CFRP布加固钢筋混凝土梁的剥离规律。结果表明,该仿真分析方法与工程实际符合较好,具有可行性和参考价值。     

Spin-transistor action via tunable Landau-Zener transitions

Spin-transistor designs relying on spin-orbit interaction suffer from low signal levels resulting from low spin-injection efficiency and fast spin decay. Here, we present an alternative approach in which spin information is protected by propagating this information adiabatically. We demonstrate the validity of our approach in a cadmium manganese telluride diluted magnetic semiconductor quantum well structure in which efficient spin transport is observed over device distances of 50 micrometers. The device is turned "off" by introducing diabatic Landau-Zener transitions that lead to a backscattering of spins, which are controlled by a combination of a helical and a homogeneous magnetic field. In contrast to other spin-transistor designs, we find that our concept is tolerant against disorder.     

日光温室的骨架结构改进及有限元分析

本文利用GBW 4 0有限元分析软件 ,提出了日光温室的骨架结构改进的方案 ,对无支柱温室 (跨度 8m)的加强拱架进行静力分析 ,结果表明 ,布置在墙体后端的拉杆承受的应力较大 ,设计时应高度重视。     

THE TREND OF THOUGHT IN PHYSICS. II

In its fundamental aspects, practically the whole of modern physics is concerned with the discussion of the relations which exist between the motions of two sets of points in such a way as to establish a sort of one-one correspondence between the things which we do, and the behavior of one set of points on the one hand, and the things which we observe and the behavior of the other set of points on the other hand. We send a beam of electrons through an X-ray tube, and certain dark lines appear on photographic plates elsewhere, or electrons are emitted with certain velocities which we measure indirectly. As regards the electrons which are emitted into our apparatus, we can almost say that we observe them directly. As regards the blackening of the photographic plate, we are content if we can account for certain electronic emissions or motions to which we can attribute it. We do not, however, try to establish a direct relation between the original beam of electrons and the photographic plate or photoelectric cell, because we find that certain other apparatus was necessary for the experiment, a calcite grating and X-ray target, and so forth. These pieces of apparatus are replaced in the mind's eye by other sets of points grouped into atoms and molecules, in a manner characteristic of the substances in such a way that we may hope to be able to establish a relation between the first set of points, those in the target, those in the calcite and those in the final photographic plate or photoelectric cell. The whole problem is to discover how the points must be assigned and what function their mutual motions are of each other in order that the correlation may be satisfactorily made.     

生长素合成关键酶基因iaaM种子特异表达载体的构建及转基因油菜的获得

生长素是重要的植物激素,它对植物的生长发育具有重要的调控作用,它能诱导营养物质向其含量高的部位运输。通过转基因技术提高内源生长素在油菜种子中的含量,诱导营养物质向种子运输,为提高油菜灌浆速度,增加产量提供了新的研究方向。iaaM基因编码的色氨酸单加氧酶是催化色氨酸(Trp)转变为生长素(IAA)的关键酶,将iaaM基因与油菜(Brassica napusL.)种子发育早期特异性表达的储藏蛋白专一性启动子(Napin)融合并插入植物表达载体pCAMBIA3301中,构建iaaM基因的种子特异表达载体,并经农杆菌介导转化甘蓝型油菜。经PPT抗性筛选、GUS组织化学检测、PCR检测,初步证实外源基因已整合进油菜基因组,获得转基因植株。     

哈尔滨石化公司柳树除絮分析

杨柳飞絮严重污染石化厂区环境,对设备空冷、水处理厂、动火作业、人员健康和交通安全有一定危害,为避免或减少飞絮带来的危害,针对哈尔滨地区飞絮的时间及特征进行了细致分析,对比更换飘絮树种（选择雄株树木）、选择抑花一号药物注射抑制、增加人工修剪及人工喷水增湿等除絮技术方法,筛选出北京园林科研所研制的抑花一号除絮效果最好,进而对哈尔滨石化公司柳树飞絮进行3a的防治应用研究。结果表明,目前柳絮发生量控制率达85％以上,通过对防絮工作的摸索和现代技术的运用,有效地减少了飞絮现象减轻了其危害。     

Gate-variable optical transitions in graphene

Two-dimensional graphene monolayers and bilayers exhibit fascinating electrical transport behaviors. Using infrared spectroscopy, we find that they also have strong interband transitions and that their optical transitions can be substantially modified through electrical gating, much like electrical transport in field-effect transistors. This gate dependence of interband transitions adds a valuable dimension for optically probing graphene band structure. For a graphene monolayer, it yields directly the linear band dispersion of Dirac fermions, whereas in a bilayer, it reveals a dominating van Hove singularity arising from interlayer coupling. The strong and layer-dependent optical transitions of graphene and the tunability by simple electrical gating hold promise for new applications in infrared optics and optoelectronics.     

Loss of caveolae, vascular dysfunction, and pulmonary defects in caveolin-1 gene-disrupted mice

Caveolae are plasma membrane invaginations that may play an important role in numerous cellular processes including transport, signaling, and tumor suppression. By targeted disruption of caveolin-1, the main protein component of caveolae, we generated mice that lacked caveolae. The absence of this organelle impaired nitric oxide and calcium signaling in the cardiovascular system, causing aberrations in endothelium-dependent relaxation, contractility, and maintenance of myogenic tone. In addition, the lungs of knockout animals displayed thickening of alveolar septa caused by uncontrolled endothelial cell proliferation and fibrosis, resulting in severe physical limitations in caveolin-1-disrupted mice. Thus, caveolin-1 and caveolae play a fundamental role in organizing multiple signaling pathways in the cell.     

Receptor-mediated transport of insulin across endothelial cells

Hormones such as insulin are transported from the interior to the exterior of blood vessels. Whether endothelial cells, which line the inner walls of blood vessels have a role in this transport of hormones is not clear, but it is known that endothelial cells can internalize and release insulin rapidly with little degradation. The transport of iodine-125-labeled insulin was measured directly through the use of dual chambers separated by a horizontal monolayer of cultured bovine aortic endothelial cells. In this setting, endothelial cells took up and released the labeled insulin, thereby transporting it across the cells. The transport of insulin across the endothelial cells was temperature sensitive and was inhibited by unlabeled insulin and by antibody to insulin receptor in proportion to the ability of these substances to inhibit insulin binding to its receptor. More than 80 percent of the transported insulin was intact. These data suggest that insulin is rapidly transported across endothelial cells by a receptor-mediated process.     

辅助钢梁加固重载铁路桥梁的动力响应分析

既有重载铁路混凝土简支双T桥梁已不能满足现在重载运输的要求,故对既有重载铁路桥梁提出一种加固方法——辅助钢梁加固法．采用列车-轨道-桥梁系统的时变动力分析理论,建立列车-轨道-桥梁系统的空间振动分析模型．本文计算了桥梁加固前后的动力响应和加固后不同速度条件下桥梁的动力响应,将计算结果与现场实车试验作了对比．计算及试验结果表明,采用辅助钢梁加固法能同时显著提高混凝土双T梁的横向和竖向刚度．因此该加固方法是合理可行的．     

土壤液土比对塿土NH4+运移阻滞因子的影响

通过土娄土不同土壤液土比条件下 NH+4 饱和流运移试验 ,定量描述了土壤液土比对 NH+4 运移阻滞因子的影响。结果表明 ,土壤液土比由 0 .36 72增加到 0 .7134 ,相应的 NH+4 饱和流运移阻滞因子由 7.494减小到4.40 9,具有明显的土壤液土比效应 ;NH+4 饱和流运移阻滞因子与土壤液土比呈极显著线性负相关。     

21世纪癌症治疗新方法——阳子线治疗法

阳子线治疗是一种在不损害正常细胞的情况下能有效杀死癌细胞的放射线治疗新技术,它可以治疗多种常规疗法难以控制的癌症,治愈率极高,并可大大提高患者的生活及生命质量.阐述了阳子线在癌症治疗中的优势,说明了应用阳子线治疗各种对应癌症的方法,最后介绍了阳子线技术及设备.     

山东沾化一次冰雹过程的数值模拟及催化防雹探讨

利用完全弹性三维冰雹云模式,模拟研究了山东沾化2008年6月25日的一次冰雹过程,分析该地区冰雹形成的物理机制,在此基础上对雹云进行催化试验并研究催化防雹机制.结果表明,冰雹主要是以冻滴为核心增长的,催化使冻滴浓度增加,粒子质量减小,向雹转化的比例降低,致使冰雹的质量和浓度减小,从而达到防雹目的.     

Multiple spectral inputs improve motion discrimination in the Drosophila visual system

Color and motion information are thought to be channeled through separate neural pathways, but it remains unclear whether and how these pathways interact to improve motion perception. In insects, such as Drosophila, it has long been believed that motion information is fed exclusively by one spectral class of photoreceptor, so-called R1 to R6 cells; whereas R7 and R8 photoreceptors, which exist in multiple spectral classes, subserve color vision. Here, we report that R7 and R8 also contribute to the motion pathway. By using electrophysiological, optical, and behavioral assays, we found that R7/R8 information converge with and shape the motion pathway output, explaining flies' broadly tuned optomotor behavior by its composite responses. Our results demonstrate that inputs from photoreceptors of different spectral sensitivities improve motion discrimination, increasing robustness of perception.