The kinesin motor KIF3A is a component of the presynaptic ribbon in vertebrate photoreceptors

Kinesin motors are presumed to transport various membrane compartments within neurons, but their specific in vivo functions, cargoes, and expression patterns in the brain are unclear. We have investigated the distribution of KIF3A, a member of the heteromeric family of kinesins, in the vertebrate retina. We find KIF3A at two distinct sites within photoreceptors: at the basal body of the connecting cilium axoneme and at the synaptic ribbon. Immunoelectron microscopy of the photoreceptor ribbon synapse shows KIF3A to be concentrated both at the ribbon matrix and on vesicles docked at the ribbon, a result that is consistent with the presence of both detergent-extractable and resistant KIF3A fractions at these synapses. KIF3A is also present in the inner plexiform layer, again at presynaptic ribbons. These findings suggest that within a single cell, the photoreceptor, one kinesin polypeptide, KIF3A, can serve two distinct functions, one specific for ribbon synapses.     

DF4型机车辅助系统运用可靠性分析与控制

通过途中故障资料的统计,对DF4型机车辅助系统各部分的运用可靠性进行分析,找出系统的薄弱环节和机车检修、保养的关键作业程序,对其进行重点监控,并提出控制性措施和改进建议.     

不同化学反应机理对爆震波模拟的影响

采用三阶TVD迎风格式和Strang-splitting算子分裂法以及H-O单步总反应和4种简化反应对爆震燃烧波进行了一维数值模拟,计算结果表明,这5种反应机理都成功起爆并且形成了爆震波.采用单步总反应方程得不到Von-Neumann压力平台区,虽然其Von-Neumann压力峰值与C-J理论最为接近,但是其峰值温度以及爆震波速度过高.采用多步反应机理能很好地捕捉到ZND结构,其爆震波速度与峰值温度能很好地与C-J值一致,采用48反应得到的诱导区长度最小.用CHEMKIN软件计算各化学反应机理得到OH质量分数,采用34反应与CHEMKIN的结果误差最小.采用多步基元反应得到的结果比采用单步总反应所得的爆震波参数更为理想,OH原子团的质量分数可以作为评价化学反应机理是否准确的一个标准.     

试论体育教学中的德育渗透

体育教学是一个多环节的教育，不仅是传授体育基本知识，运动技能，更是培养学生良好的组织纪律性、高尚的体育道德作风、顽强的意志品质和浓厚的学习兴趣的主要途径。在体育教学中渗透德育，能使教学任务顺利完成，实现教书育人的目的。     

MEADOW: a middleware for efficient access to multiple geographic databases through OpenGIS wrappers

With the proliferation of various geographic databases on the Internet, we have seen increasing needs for accessing them concurrently and remotely via the Web for high‐level decision making. In this paper, we present Middleware for Efficient Access to Databases through OpenGIS Wrappers (MEADOW), an object‐oriented middleware system we have developed to meet these needs. Current OpenGIS standard addresses many interoperability issues involved in such a global utilization of geographic databases. However, existing Simple Feature specification for CORBA (SFCORBA) implementations of OpenGIS proved to be insufficient for MEADOW. The main problems are the complexity of system development and maintenance, and the inefficiency of accessing remote data servers for processing region queries. We resolved the complexity problem by automatically generating a major portion of the application code, specifically wrappers on database servers and client library modules called transparent access providers. A MEADOW view definition language was developed as a high‐level specification language for this purpose. The efficiency problem was resolved by using a region‐based group prefetching of spatial objects from a geographic region. In addition, we implemented an OID‐based semijoin for efficient global query processing, and a region‐level locking to enhance the level of concurrency among region queries. Copyright © 2002 John Wiley & Sons, Ltd     

Physicochemical characterization of YJA20379-8, a new proton pump inhibitor

The physicochemical properties of the potent reversible proton pump inhibitor YJA20379-8, 3-butyryl-4-[(R)-1-methylbenzylamino]-8-ethoxy-1,7-naphthyridine, were studied. YJA20379-8 is essentially nonhygroscopic pale yellowish crystalline powder. It is practically insoluble in water, and its lipid solubility is high. The pH solubility profile exhibits an L-shaped curve, indicating YJA20379-8 is a basic substance having a soluble ionized form in acidic conditions. This is consistent with the result of an experiment to determine pKa. The solid-state stability study shows that YJA20379-8 is stable at various temperatures and humidities, but is decomposed by light.     

Efficient diffusive reflector-type diode side-pumped Nd:YAG rod laser with an optical slope efficiency of 55%

We fabricated a compact diode side-pumped Nd:YAG laser with a diffusive reflector, in which the diode laser power is transferred directly into the threefold symmetric diffusive cavity through long narrow slits. With a 7.5% output coupler in a linear resonator, we obtained 62.4-W multimode output power with an optical slope efficiency of 53.4% at a diode power of 182 W, which corresponds to an optical-to-optical efficiency of 34.3%. The optical slope efficiency increased to 55.5% when we used an 11% output coupler. From the leakage power analysis method, the pumping efficiency was measured to be approximately 82%. We discuss the thermal lens and the slope efficiency with respect to absorbed power that is derived from the measured pumping efficiency.     

Study on I-V Behavior of YBCO Film on 5 mm × 10 mm LAO Under DC Pulse by Electric Transport Method

Journal of Superconductivity and Novel Magnetism - A set of DC pulse devices was built to measure the 5 mm?×?10 mm YBCO sheet in order to evaluate the impact of...