Three ways to implement interfacial techniques: application tomeasurements of chromatic dispersion, birefringence, and nonlinearsusceptibilities

Depending on the spectal width of the source illuminating an interferometer, measurement procedures can utilize either the whole interferogram, or only the fringe envelope, or only the fringe quick oscillations. With an ultraband spectrum source, a simplified adaptation of the methods of Fourier transform spectroscopy yields the variations of the test-fiber propagation constant over the whole wavelength-interval of the source. Chromatic dispersion can then be computed from a single interferogram. With narrower spectrum sources, only the fringe envelopes are utilized and yield measurements of mode delay, with application to chromatic and polarization mode dispersion. In this case, however, interferograms at several wavelengths are necessary. With even narrower spectrum sources, the fringe quick oscillations provide measurements of phase shifts, related to changes in the mode propagation constant, when outside perturbations are applied to the test fiber. A direct method for measuring the third-order nonlinear susceptibilities is discussed. In this case the outside perturbation is an intense pump laser field     

Polymer aqueous solutions as quenching media. II. Ethylene oxide–propylene oxide copolymers

The cooling power of aqueous solutions of ethylene oxide-propylene oxide copolymers are studied with a silver standard sample by using two apparatuses quench with injection and quench with agitation. For temperature T>400°C, the viscosity plays the predominant role; for T<400°C, the cooling is controlled by the polymer precipitation and the cooling rate decreases by lowering the cloud point of the polymer solution. This work demonstrates the possibility of adjusting the cooling curves by taking into account the thermodynamical properties of the polymer.     

A single phase model of mechanisms effecting miscible surfactant oil recovery

The concept of volume averaging is used to theoretically study the mechanisms of mass dispersion, adsorption, and dead-space volume. These mechanisms are important to the understanding of miscible surfactant flooding. After simpiffication based on order-of-magnitude scaling, a linear core model is solved using state variable finite-difference techniques. Mass dispersion and adsorption are shown to be important model parameters while dead-space volume is a rather insensitive model parameter.     

冠带层新平台技术

子午线轮胎出现不久，就采用钢丝带束层代替了纤维带束层，这对于实现子午线轮胎提高使用寿命和改善操纵性能的潜能是必要的。     

Visiting pebbles on rectangular grids: coordinating multiple robots in mobile fulfilment systems

Intelligent Service Robotics - Multi-robot path finding and coordination is one of the key performance-affecting subsystems of the overall robotic order fulfilment process for use in warehouse...     

Thin and thick YBCO films grown by MOCVD processes. Study of the angular magnetic field dependence of current transport properties

Thin and thick YBCO Films have been grown by Aerosol Assisted as well as by thermal MOCVD. The Aerosol Assisted MOCVD technique allows the growth of YBCO films from a single liquid source at deposition rates of up to 10m/h.Transport measurements (I-V) on etched microbridges using a single pulse technique have been performed. The angular magnetic field dependence J_c() of the critical current density from T_c down to 50 K has been measured. Transport properties are reported and discussed with respect to the microstructural features as determined by X-ray diffraction and electron microscopy.     

The influence of spin on second sound in superfluid3He-4He mixtures

The second-sound velocity of a superfluid mixture increases when a static and homogeneous magnetic field is applied. In particular, for dilute mixtures (molar ³ He concentration <0.1) and low temperatures, (0.1<T<0.6 K) the relative velocity increase is independent of concentration and is given by u ₂/u ₂5×10^–16 B _e ² T ^–2. It should be easily observed wheneverB _e T ^–1is larger than 10 ⁵ G K^–1 and can lead to a novel measurement of the magnetic susceptibility.     

A Model for Studying Velocity Variations in Unmyelinated Axons

A simple electrical model of the nerve axon is presented. The only non-linear element in the model is the sodium conductance, which is assumed to vary in a step-like way. This allows the propagation velocity for action potentials to be expressed analytically. The aftereffects from an action potential are generally slow. By considering them quasi-stationary, the velocity of a subsequent action potential can be calculated and compared with that of the first one. Considering the effects of afterpotential and afterconductance, it is shown that the theory adequately describes the variations in propagation velocity in the squid giant axon for action potentials separated by 3 ms to 14 ms.     

BK Polyomavirus bkv-miR-B1-5p: A Stable Micro-RNA to Monitor Active Viral Replication after Kidney Transplantation

Background: Bkv-miR-B1-5p is a viral micro-RNA (miRNA) specifically produced during BK polyomavirus (BKPyV) replication. Recent studies have suggested using bkv-miR-B1-5p as a biomarker to monitor viral infection and predict complications in kidney transplant patients. To identify the technical limitations of this miRNA quantification in biological samples, knowledge of its stability and distribution in the extracellular compartment is necessary. Moreover, a proof of concept for using bkv-miR-B1-5p as a biomarker of active replication in chronic infection is still missing in the published literature. Methods: The stability of bkv-miR-B1-5p was evaluated in samples derived from cell cultures and in urine from BKPyV-infected kidney transplant recipients. The miRNA was quantified in different fractions of the extracellular compartment, including exosomes, and protein binding was evaluated. Finally, we developed an in vitro model for chronic culture of BKPyV clinical isolates to observe changes in the bkv-miR-B1-5p level during persistent infections. Results: Bkv-miR-B1-5p is a stable biomarker in samples from humans and in vitro experiments. Marginally associated with the exosomes, most of the circulating bkv-miR-B1-5p is bound to proteins, especially Ago2, so the miRNA quantification does not require specific exosome isolation. The bkv-miR-B1-5p level is predictable of viral infectivity, which makes it a potential specific biomarker of active BKPyV replication after kidney transplantation.