Frequency up-conversion by stimulated hyper-Raman scattering

Stimulated electronic hyper-Raman scattering has been obtained in lithium vapor via excitation of several two-photon resonances (2s-3d, 2s-4s, 2s-4d) with a pulsed dye laser. The wavelength of the generated radiation was shorter than the pump wavelength and tunable over a few nanometers. The tuning behavior of the hyper-Raman laser was influenced by two-photon induced self-focusing/self-defocusing effects.     

Calculation of serum digoxin levels in patients with normal and impaired renal function

Serum digoxin levels were examined in 55 patients with varying degrees of renal function impairment who were receiving chronic oral digoxin therapy. Three methods of predicting digoxin serum levels were investigated. Each method may be applied using serum creatinine values and does not require urinary data. Correlations between calculated and actual digoxin levels in combined male and female patients were improved when changes in digoxin distribution volumes in renal impairment were considered. Correlations between calculated and actual digoxin levels were poor in male patients but were again improved by incorporating changes in drug distribution volume. Correlations obtained in female patients were superior to those obtained in male patients and appeared to be independent of the method of calculation employed.     

编码多载波CDMA在下行Rice衰落信道下的性能分析

文中讨论了一种新的CDMA体制,即将OFDM调制技术应用于CDMA的MC-CDMA。从理论上分析了编码MC-CDMA经过下行Rice衰落信道的性能,针对接收端采用分集与Viterbi译码相结合的接收技术,给出下行链路的误码率表达式,并模拟了性能曲线。     

Compounding and characterization of recycled multilayer plastic films

Mechanical recycling of multilayer plastic films from food packages was investigated. The multilayer films were manually separated from municipal solid waste, washed, grinded, and finally compounded at 0–100 wt% concentrations with virgin low-density polyethylene (PE-LD). Polyethylene grafted with maleic anhydride (PE-g-MA) compatibilizer was used in two of the compounds to replace 2 and 5 wt% of the PE-LD to study its effect as well. PE-g-MA is expected to improve the mechanical properties of the compounds by promoting the adhesion between incompatible polymer phases. The composition of the compounds was characterized with Fourier-transform infrared spectroscopy and differential scanning calorimetry and their properties were studied with tensile testing and rotational rheometer measurements. All tested compounds had relatively good mechanical properties and processability. This indicates that recycled multilayer films could replace at least part of the virgin PE-LD in applications where high-thermal stability or good visual appearance is not required. The PE-g-MA compatibilizer did not have a significant effect on the mechanical properties of the compounds.     

Determination of polycyclic aromatic hydrocarbons (PAH) in edible vegetable oils by liquid chromatography and programmed fluorescence detection. Comparison of caffeine complexation and XAD-2 chromatography sample clean-up

Two clean-up procedures were compared for the analysis for polycyclic aromatic hydrocarbons (PAHs) in edible vegetable oils. One method comprises a liquid-liquid extraction followed by XAD-2 chromatography and the other a caffeine-formic acid complexation. The clean-up step is followed by gradient reversed-phase HPLC in combination with wavelength-programmed fluorescence detection. Due to better repeatability and simplicity, the XAD-2 method was selected for the determination of PAHs in 14 different vegetable oils. Between the different oil samples large differences were observed in PAH concentrations. PAH concentrations in vegetable oils sampled from the Dutch market appear to be comparable with those found in other countries.     

Flat pressed wood plastic composites made of milled foam core particleboard residues

Flat pressed wood plastic composites were produced on a laboratory-scale using residues of lightweight foam core particleboards as raw material. Raw material preparation methods (dry blending and compounding with a twin screw extruder) and the wood flour content (WF) loading, as influencing parameters on the panel properties, were varied, and coupling agents (CA) were added in some variations. The results showed that panels produced with lower WF content (75 %) have better physical and mechanical properties compared to those of higher WF. The CAs only influenced the panel properties when they were added during the compounding of the materials. Due to the assumed higher wood degradation resulting from raw material compounding, the panel properties were inferior to the panels produced with dry blended materials.     

Inhibition of Leishmania infantum Trypanothione Reductase by Azole‐Based Compounds: a Comparative Analysis with Its Physiological Substrate by X‐ray Crystallography

Herein we report a study aimed at discovering a new class of compounds that are able to inhibit Leishmania donovani cell growth. Evaluation of an in‐house library of compounds in a whole‐cell screening assay highlighted 4‐((1‐(4‐ethylphenyl)‐2‐methyl‐5‐(4‐(methylthio)phenyl)‐1H‐pyrrol‐3‐yl)methyl)thiomorpholine (compound 1 ) as the most active. Enzymatic assays on Leishmania infantum trypanothione reductase (LiTR, belonging to the Leishmania donovani complex) shed light on both the interaction with, and the nature of inhibition by, compound 1 . A molecular modeling approach based on docking studies and on the estimation of the binding free energy aided our rationalization of the biological data. Moreover, X‐ray crystal structure determination of LiTR in complex with compound 1 confirmed all our results: compound 1 binds to the T(SH)₂ binding site, lined by hydrophobic residues such as Trp21 and Met113, as well as residues Glu18 and Tyr110. Analysis of the structure of LiTR in complex with trypanothione shows that Glu18 and Tyr110 are also involved in substrate binding, according to a competitive inhibition mechanism.     

W-CDMA系统中辅同步信道捕获的改进

W-CDMA系统中,各基站之间是异步时序关系。为了快速识别基站,3GPP协议引入了三步同步的小区搜索算法。第二步对辅同步信道的搜索是极其重要的。采用传统的匹配滤波器组结构运算复杂度比较大。该文分析了辅同步信道的结构,根据其构造特性提出了部分快速哈达玛变换(PFHT)的快速算法。理论分析证明该算法减少了接近70％的运算量。同时,针对辅同步信道的RS码表搜索,提出了一种分布式子图搜索算法,与穷举搜索相比,大幅度降低了复杂度。经过这两方面的改进,使辅同步信道捕获的硬件设计复杂度大大降低,对于工程应用具有重要价值。     

Novel subunit composition of a renal epithelial KATP channel

Unique ATP-inhibitable K+ channels (KATP) in the kidney determine the rate of urinary K+ excretion and play an essential role in extracellular K+ balance. Here, we demonstrate that functionally similar low sulfonylurea affinity KATP channels are formed by two heterologous molecules, products of Kir1.1a and cystic fibrosis transmembrane conductance regulator (CFTR) genes. Co-injection of CFTR and Kir1.1a cRNA into Xenopus oocytes lead to the expression of K+ selective channels that retained the high open probability behavior of Kir1.1a but acquired sulfonylurea sensitivity and ATP-dependent gating properties. Similar to the KATP channels in the kidney but different from KATP channels in excitable tissues, the Kir1.1a/CFTR channel was inhibited by glibenclamide with micromolar affinity. Since the expression of Kir1.1a and CFTR overlap at sites in the kidney where the low sulfonylurea affinity KATP are expressed, our study offers evidence that these native KATP channels are comprised of Kir1.1a and CFTR. The implication that Kir subunits can interact with ABC proteins beyond the subfamily of sulfonylurea receptors provides an intriguing explanation for functional diversity in KATP channels.     

An architecture for exporting environment awareness to mobilecomputing applications

In mobile computing, factors such as add-on hardware components and heterogeneous networks result in an environment of changing resource constraints. An application in such a constrained environment must adapt to these changes so that available resources are properly utilized. We propose an architecture for exporting awareness of the mobile computing environment to an application. In this architecture, a change in the environment is modeled as an asynchronous event that includes information related to the change. Events are typed and are organized as an extensible class hierarchy so that they can be handled at different levels of abstraction according to the requirement of each application. We also compare two approaches to structure an adaptive application. One addresses the problem of incorporating adaptiveness into legacy applications, while the other considers the design of an application with adaptiveness in mind