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The wear behavior of an as-received Mg-Zn-Y-Zr alloy before and after a facile heat treatment was investigated under sliding in air and 0.5 wt.% NaCl solution. Results revealed that the wear resistance of the alloy was remarkably enhanced after the heat treatment, irrespective of testing condition. The wear mechanism was predominantly abrasive wear accompanied by oxidation under the dry sliding condition, while corrosive wear was dominant under sliding in the NaCl solution. The superior corrosive wear resistance was attributed to the homogenous distribution of fine I-phase precipitates in the alloy by the heat treatment, leading to a reduction in wear, corrosion as well as wear-corrosion synergy. The wear-accelerated corrosion rate was remarkably alleviated after the heat treatment.

Fluidized bed reactor Fenton (FBR-Fenton) process was adopted for reverse osmosis concentrate (ROC) treatment with three types of carriers, including sand, zeolite and granular activated carbon (GAC). Adsorption studies demonstrated that GAC achieved the best adsorption performance (maximum COD removal of 78% in 15 h) among the three carriers, and the adsorption of ROC organic matters followed a two-stage adsorption model. Fenton oxidations were carried out in three fluidized beds after column saturation, and FBR-Fenton/GAC process achieved highest COD removal (72%) and most BOD5/COD ratio enhancement (from 0.03 to 0.3) in ROC. Long-term operation data demonstrated good performance stability of GAC as the carrier. In addition, GAC fluidized bed obtained highest total iron removal rate via iron crystallization process. Continuous in-situ GAC regeneration with more than 90% recoveries of surface area, pore volume and adsorption capacity were observed along the ROC treatment with FBR-Fenton/GAC process. Mechanism studies revealed that better COD removal performance in FBR-Fenton/GAC process was attributed to the combining effects of homogenous Fenton reaction, GAC adsorption and GAC/H2O2 catalytic reaction.

Sulphonylurea (SU) stimulates insulin secretion by pancreatic beta-cells and is generally used as a first-line treatment for type 2 diabetes. However, after long-term SU treatment (six months or over), some patients begin to show an increase in blood glucose once again (secondary SU failure). Two theories have been put forward to explain this failure--dysfunction of the proinsulin conversion machinery or insulin resistance. However, the primary pathogenesis behind secondary SU failure still needs to be investigated. Using a reliable technique that specifically identifies intact proinsulin (IPI), total proinsulin (TPI) and specific insulin (SI), this study aims to discover if a defect in the proinsulin converting mechanism plays a role in SU failure. Three groups were recruited for this study: healthy controls (n=8), SU responders (n=38) and secondary SU failures (n= 46). Serum concentrations of insulin-related molecules released in response to a standard glucose challenge test were compared between the groups. It was found that total SI was lower in the patient groups (P0.05 compared to the control group), while TPI and IPI showed no distinct difference between the three groups (P0.05). TPI:SI ratio and IPI:SI ratio showed marked increases in the patient groups (P0.05 compared to control group), with no obvious quantitative difference between SU responders and secondary SU failures (P0.05). Similar results for the Homa Insulin Resistant Index were found between the two patient groups. Interestingly, blood glucose at 180 mins after glucose challenge was significantly higher in the secondary SU failure group (P0.05), with no correlation to SI, while the SU responder group showed good correlation between the parameters (P0.05). We conclude that type 2 diabetes is associated with obvious dysfunction in the proinsulin-converting process and shows severe SI deficiency in responding to glucose challenge. Dysfunction of the proinsulin conversion mechanism was not an extra cause responsible for SU failure.

Studying quantitative relationships between landscape pattern and water quality is a fundamental step to assess the impacts of non-point source pollution. Many hydrological models with multi-functionality have been developed as useful tools to study several key mechanisms in non-point source pollution. In landscape ecological studies, however, the empirical modelling approaches have been dominated with emphasis on the relationships between the landscape metrics and water quality indices. The main techniques for developing those models of landscape-water quality are statistical regression analysis based on linear models. In this article, Allometric models and the traditional multiple linear regression models for estimating the linkage between landscape metrics and water quality were tested in Sihu Basin, Hubei Province, China. The models at patch class level were established in 24 hydrological units of the basin, which took nine water quality indices (EC, pH, SS, DO, COD, TN, TP, NO3--N, NH4+-N) as the dependent variables and eighteen landscape metrics calculated in FRAGSTATS 3.3 as independent variables. The results suggested that, compared with the traditional multiple linear regression models, Allometric models were more suitable for SS, DO, TP, TN, NH4+-N, in which landscape pattern metrics could explain the 80.5%, 77.7%, 58.2%, 43.9%, 67.6% of total variation, respectively. There had little difference between multiple linear regression models and Allometric models for EC and NO3--N. The coefficients of determination in Allometric models were not as strong as that obtained in the multiple linear regression models for pH and COD. The above results indicated that using Allometric model may potentially provide a new way to study the linkage between landscape metrics and water quality indices, which will help protect our regional water resources.

Pd-Cu is a well-known alloy for H-2 separation membranes. Using a new optical combinatorial method we determined the H-2 permeability of Pd-Cu alloys at room temperature in relation to their crystal structure and microstructure. Compositional gradient samples allow us to determine the intrinsic permeability as a function of the alloy composition. From a detailed XRD, TEM and AFM analysis we find that the pure fcc and bcc phases have a very low permeability, whereas the mixed bcc/fcc phases show the highest permeability for thin film alloys prepared at higher temperatures. Therefore interstitial-bulk hydrogen diffusion is most probably not the main transport mechanism. Instead we argue that the hydrogen transport occurs mainly along the heterogeneous grain boundaries. As compared to the bulk phase diagram we find that the mixed bcc/fcc region in our Pd-Cu thin films is larger than reported in literature (ranging from 43 at% -65 at% Pd at 483 K). Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Although widely used, the most promising Li-based technologies still need to seek new materials concepts to satisfy the increasing demands for energy storage worldwide. We report a layered electrode material, Cu 2.33 V 4 O 11 , for which the valency of copper, vanadium and thus indirectly the oxygen stoichiometry need to be investigated during the electrochemical cycle. High-resolution electron energy loss spectroscopy (HREELS) allows us to perform these measurements at the nanometer scale.

Background: it is necessary to enhance the efficiency of amplification of Y-STR in according with the progress in forensic science. Methods: Using a multiplex of Y-STRs and amplify simultaneously three Y-STRs loci. Results: A multiplexing system of three Y-STR loci (DYS390, DYS391 and DYS393) is successfully established followed by a population genetic study of Han population in Chengdu, China. Conclusions: The diversity of haplotype is 0.8965, the value of discrimination and the chance of exclusion chance is 0.8965 with the standard error 0.0081. This established system is one of the good tools in personal identification and genetic study.

Background : X-chromosome (ChrX) STR loci have been proven to be a useful tool for paternity testing, especially in some cases. In paternity testing, genetic markers on ChrX are only applicable when the disputed child is female. Methods : The author investigated allele frequency distribution of ChrX STR loci DXS6789 and HumSTRX1 in a sample of unrelated individuals (males and females) in Han population living in Chengdu, China, by using PCR and PAGE followed by silver staining. Results : Ten and six different alleles of DXS6789 and HumSTRX1 loci were detected, respectively. The genotype frequencies of DXS6789 and HumSTRX1 loci were in good agreement with the Hardy–Weinberg equilibrium. The observed heterozygosity of DXS6789 and HumSTRX1 loci were 0.795 and 0.748 in females, respectively. Conclusions : It is suggested that these ChrX markers are appropriate for the purposes of forensic analyses.

Searching for effective Smad3 gene-based gene therapies for hepatic fibrosis, we constructed siRNA expression plasmids targeting the rat Smad3 gene and then delivered these plasmids into hepatic stellate cells (HSCs). The effect of siRNAs on the mRNA levels of Smad2, Smad3, Smad4, and collagens I-α1, III-α1 and IV-α1 (Colα1, Col3α1, Col4α1, respectively) was determined by RT-PCR. Eighty adult male Sprague-Dawley rats were randomly divided into three groups. Twice a week for 8 weeks, the untreated hepatic fibrosis model (N = 30) and the treated group (N = 20) were injected subcutaneously with 40% (v/v) carbon tetrachloride (CCl4)-olive oil (3 mL/kg), and the normal control group (N = 30) was injected with olive oil (3 mL/kg). In the 4th week, the treated rats were injected subcutaneously with liposome-encapsulated plasmids (150 µg/kg) into the right liver lobe under general anesthesia once every 2 weeks, and the untreated rats were injected with the same volume of buffer. At the end of the 6th and 8th weeks, liver tissue and sera were collected. Pathological changes were assessed by a semi-quantitative scoring system (SSS), and a radioimmunoassay was used to establish a serum liver fibrosis index (type III procollagen, type IV collagen, laminin, and hyaluronic acid). The mRNA expression levels of the above cited genes were reduced in the HSCs transfected with the siRNA expression plasmids. Moreover, in the treated group, fibrosis evaluated by the SSS was significantly reduced (P < 0.05) and the serum indices were greatly improved (P < 0.01). These results suggest that Smad3 siRNA expression plasmids have an anti-fibrotic effect.

We report a new method for the fabrication of sub-10 nm nanopores in a fast single process step. The pore formation is accomplished by exploiting the competition between sputtering and deposition in ion-beam-induced deposition (IBID) on a thin membrane. The pore diameter can be controlled by adjusting the ion beam and gas exposure conditions. The pore diameter is well below the limit that can be achieved by focused ion beam (FIB) milling alone. There is no need of preparation and successive treatments. Apart from simplicity and speed, this method offers an additional advantage of a broad choice of material and thickness of the deposit and the membrane.

From conductance and noise studies, we infer that nanometer-sized gaseous bubbles (nanobubbles) are the dominant noise source in solid-state nanopores. We study the ionic conductance through solid-state nanopores as they are moved through the focus of an infrared laser beam. The resulting conductance profiles show strong variations in both the magnitude of the conductance and in the low-frequency noise when a single nanopore is measured multiple times. Differences up to 5 orders of magnitude are found in the current power spectral density. In addition, we measure an unexpected double-peak ionic conductance profile. A simple model of a cylindrical nanopore that contains a nanobubble explains the measured profile and accounts for the observed variations in the magnitude of the conductance.

We report the effects of biaxial strain on the charge ordering temperature Tco of the mixed-valent manganite perovskite oxide Pr0.5Ca0.5MnO3. Thin films were grown on SrTiO3, which has a 1.3% larger in-plane lattice parameter. Other substrates were used for comparison. Transport measurements combined with data from electron microscopy show that Tco is considerably enhanced. At thicknesses of the order of 10?nm, where the films are fully strained, Tco is above 320?K, more than 70?K above the bulk value of 250?K, while around 50?nm, where relaxation has set in, the enhancement is around 40?K. The bulk value is only reached at a thickness of about 150?nm.

In this paper, a novel silicon micromachining using CO2 laser has been demonstrated for the first time. The wavelength of CO2 laser is 10.64 mum and not absorbed by silicon material. So, it cannot do any micromachining for pure silicon. However, as we put a silicon on the top of a glass material, CO2 laser can etch the silicon, even etch through the wafer to be a hole structure. For example, a silicon hole of 525 mum deep can be obtained by CO2 laser machining circular shape for 80 passes at power of 24 W, spot size of 76 mum and scanning speed of 6 mm/sec. In comparison with conventional laser micromachining of silicon, shorter wavelength lasers e.g. Nd:YAG laser with wavelength of 1.06 mum and excimer laser of 248 or 193 nm are used due to the good adsorption of silicon. But the cost of shorter wavelength laser is much higher than CO 2 laser. In comparison with conventional silicon micromachining by dry plasma etching, wet KOH/TMAH etching or wire electrodischarge grinding (WEDG), CO2 laser micromachining is much easier, cheaper and has faster etching rate than plasma etching, and more flexible to make different geometry than wet etching and WEDG. This CO2 laser micromachined silicon technology will be a promising one for the application of microfabrication and MEMS

This paper reports on self-aligned T-gate InGaP/GaAs FETs using n/sup +//N/sup +///spl delta/(P/sup +/)/n structures. The N/sup +/-InGaP//spl delta/(P/sup +/)-InGaP/n-GaAs structure forms a planar-doped barrier. An over-etch n/sup +/-GaAs/N/sup +/-InGaP layer offers the implement of self-aligned T-gate by an highly selective etch between the InGaP and a GaAs layers. A fabricated device with an effective gate length of 1.5/spl times/100 (0.6/spl times/100) /spl mu/m/sup 2/ exhibits an extrinsic transconductance, unity-current gain frequency, and unity-power gain frequency of 78 (80) mS/mm, 9 (19.5), and 28 (30) GHz, respectively. Moreover, all proposed devices show good dc and ac linearity.

Electron diffraction and high resolution microscopy have been performed on Mg1-xAlxB2 with x~0.5. This composition displays a superstructure with a repeat period of exactly 2c along the c axis and about 10 nm in the a-b plane. The superstructure results in ring-shaped superreflections in the diffraction pattern. Irradiation by a strong electron beam results in a loss of the superstructure and a decrease of about 1% in the c lattice parameter. In-situ heating and cooling on the other hand showed that the superstructure is stable from 100 K to 700 K. Possible origins for the superstructure are proposed.

A high-dimensional sparse signal usually should be realigned as a long 1D signal to be recovered by orthogonal matching pursuit (OMP), an efficient algorithm for compressed sensing. Clearly, however, the realigned long signal will result in a large amount of computation in OMP. If each atom in the dictionary can be expressed as the Kronecker product of two vectors, it can possible to decompose this dictionary into two sub-dictionaries. By exploiting this property, a fast OMP algorithm for 2D sparse signals of this kind is presented, and applied to 2D angle estimation in MIMO radar. Simulation results verify its good reconstruction quality approximate to that of OMP and greatly improved computational efficiency.

A novel approach to silicon (Si) etching has been demonstrated using glass assisted CO(2) laser processing. Conventional Si etching can be performed by wet etching, dry etching, Nd:YAG or UV lasers. No CO(2) laser was used to etch Si due to the absorption problem. We have etched Si with the assistance of glass beneath the Si. This approach changes light absorption behavior of Si and makes Si be etched from the top surface toward the interface. The new mechanism was discussed in viewpoint of the variation of electronic band structure, surface oxidation and light absorption of Si at high temperature.

~TREPTOMYCIN alone somethnes will cure tuberculous meningitis, formerly J a uniformly fatal dlsease. ~ ourteen patients wAh thls condltlon ]n thls hospital were given streptomycin alone; eleven died and three recovered, s However, Lincoln's results with combined streptomycin and Pro,mizole were so mueh more promising, 4 that we treated sixteen patients with a slight modification of her regimen. Patienls.--From June, 1948, to April, 1949, thirty-two patients suffering from tuberculous meningitis were admitted to The Shanghai Public IIospital for Children. Sixteen of them were treated with combined streptomycin and Promizolc, and six with streptomycin alone. The other ten were admitted too late in the course of the disease, died within one or two days of admission, or were discharged against advice soon after admission. Except for these drugs, al! of these patients received the same treatment. Of the sixteen patients treated with streptomycin and Promizole, the threeto four-month course of combined therapy was completed in six; five were treated for more than two months, and five, who are not included in this series, were observed for less than one month On admission, in addition to a careful history, physical examination, and routine laboratory tests, the following procedures were carried out : x-ray fihn of chest, examination of the fundi, testing of the eighth nerve, tuberculin test (PPD), sedimentation rate (ESR), plasma cholesterol determination, and cerebrospinal fluid examinations, including eell count, differential count, sugar, protein, and chloride determinations, and a seareh for tubercle bacilli by smears, B5wenstein.'s culture medium, or animaI inoculation. When the diagnosis had been established and treatment started, the above examinations and tests also were done daily or periodically as indicated. Treatment.--Streptomycin was given intramuscularly (0.1 to 0.2 Gin., every four ho,urs, according to the age and size of the patient, for from three to four' months) and intratheeally (25 to 50 rag. daily for thir ty days, and then every two days for sixty days). Also, from 1 to 1.5 Gin. of Promizole were given orally every day. It may be continued for from one to two years. In addition to the ordinary ward diets, extra nutrition, e.g., cow's milk, eggs, vitamins A, B~, By, C, and D were added. Patients who could not take food by mouth were fed by nasal feedings and those who vomited frequently were given fluids parenterally and Mood intravenously. As measles and whooping cough are the most serious complications of tuberculosis and may cause a relapse of tuberculous'meningitis, adult blood and immune globulin were given to prevellt

Multiple loop linear time invariant feedback systems stability, discussing conditions, gain matrix and input-output properties

Nonlinear time varying discrete feedback systems input-output properties, deriving stability criteria by generalized small gain and passivity theorems