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In this paper, the electrical tree growth characteristics of silicone rubber (SiR) are studied under impulse superimposed on DC voltage and a temperature gradient (TG) field. The temperature difference between high voltage (HV) and ground (GD) electrodes varies from -90 to 90 °C resulting in a TG field in the samples. The electrical tree morphology, length and accumulated damage are discussed. Experimental results show that with the increase of absolute value of TG, the electrical tree length and accumulated damage continue to increase, and the tree morphology turns from branch-like tree to bush-branch hybrid tree. The positive TG has a more obvious acceleration effect on the tree growth than does the negative TG. Under the TG, the temperature dependent carrier transport results in space charge accumulation and electric field distortion at low temperature side, which is the main reason for the different growth characteristics of electrical tree. Besides, the accumulated damage of DC superimposed with heteropolar impulse voltage is larger than that under DC superimposed with homopolar impulse voltage. It is concluded that the temperature gradient and impulse superimposed on DC voltage promote the electrical tree growth of HVDC cable accessories insulation.

In this paper, graphene/silicone rubber (SiR) nanocomposites with filler contents of 0.001–0.005 wt% are prepared to improve electrical tree inhibiting ability under different temperature gradients. The electrical treeing test is performed under three temperature gradients by controlling the temperature of high voltage and ground sides. Experimental results indicate that the SiR sample with 0.003 wt% graphene presents the best performance on electrical tree resistance. The tree length and accumulated damage are both reduced with the increase of graphene content from 0 to 0.003 wt%, but increased with the further increase of filler content from 0.003 to 0.005 wt%. The tree outline tends to be circular in neat SiR under negative temperature gradient, while it is triangular under positive temperature gradient. However, the effect of temperature gradient is weakened when graphene exists. Based on quantum dot models, the role of graphene quantum wells (QWs) in the regulation of charge transport and electrical tree resistance in SiR is revealed. This research provides an effective method to suppress electrical trees of SiR for cable accessories.

In this work, nano-titanium oxide (TiO 2 ) is encapsulated into boron nitride nanosheets (BNNS) by the calcination process to fabricate core-shell structured TiO 2 @BNNS nanofillers. The effects of TiO 2 @BNNS fillers on the DC conductivity, space charge and breakdown strength of polypropylene (PP) composites are investigated. Experimental results show that PP/TiO 2 @BNNS composites have a lower temperature-dependent conductivity with an activation energy of 0.64 eV, which is much lower than that of PP, 0.95 eV. The DC breakdown strength of PP/TiO 2 @BNNS samples is 22.2% higher than that of PP at 90 °C. The average space charge density and electric field distortion rate of PP/TiO 2 @BNNS are reduced by 6.6 C/m3 and 23.3%, respectively, compared with PP, under a polarization electric field of 40 kV/mm at 90 °C. It is proven that TiO 2 @BNNS nanofillers form numbers of electrical potential wells for charge carriers, thereby, inhibiting the hot electron transport and their damage to polymer molecules. This work provides an effective method to improve the dielectric performance of PP cable insulation.

The cross-linked polyethylene insulation of power cables under multiple stresses will age and deteriorate, and eventually cause insulation failure, which threatens the reliability of transmission lines. In this contribution, based on Direct Current Integrated Charge method, the performances of XLPE under thermal aging are investigated. The results show that the charge minimally injects into the unaged XLPE insulation, and the charge injected behavior intensifies with the thermal aging time. Thermal aging treatment results in greater relative permittivity, volumetric conductivity, and absorbed charge of XLPE insulation. The permittivity of the aged XLPE insulation gradually increases by 18.24%, whereas the conductivity rises by 14.48 times, and the absorption charge shoots up by 18.03 times. It is conducted that the enhancement in charge injection and the acceleration of charge accumulation reflects the cable insulation thermal aging intensified.

Nanodielectrics have been one of the research hotspots in electrical insulation, since the concept was proposed in 1994. Numerous studies have shown that nanocomposites had better electrical, thermal and mechanical performances than microcomposites and undoped polymers. Especially, their excellent electrical properties, including low conductivity, high breakdown strength as well as suppressed space charge accumulation, make it possible to be the new generation of insulating materials, for instance, polyethlene-based nanocomposites for HVDC cables. These profound properties are thought to be ascribed to the great number of polymer-filler interfacial regions, ascribed to the high specific surface area of nanofillers. Graphene nanoplatelets, as a unique nano-scaled filler with a thickness of only an atomic layer, has an enormous specific surface area up to 2630 m2/g, which can significantly increase the polymer-filler interfacial regions in theory and advantage to exploit the further potentials of insulating nanodielectrics for HVDC cable application.

The role of active element titanium for the bonding alumina substrates using Sn3.5Ag4Ti(Ce,Ga) alloy filler at 250 °C in air was studied. The influence of soldering time on the microstructure and element distribution was investigated. It was observed that the Sn3.5Ag4Ti(Ce,Ga) solder could wet the alumina well under the agitation of external force. No continuous reaction products could be detected at the alumina/solder interface by using scanning electron microscopy and X-ray diffractometer. It might be inferred that the joining could be accomplished by chemical adsorption of Ti on the alumina/solder interface, regardless of whether or not an interfacial reaction layer is formed. The theoretical analysis of the Ti element adsorption at the alumina/solder interface was tried. Results can further explain the adsorption phenomenon of Ti at the interface prior to bond formation. In the case of environmental temperature has yet to meet the chemical reaction conditions, the chemical adsorption between active elements and alumina can get good bond as well. The shear strengths of the soldered Al2O3/Al2O3 substrates with the soldering time of 15 min, 30 min, and 1 h were measured to be 15.46, 16.15, and 17.39 MPa respectively.

Antibody-mediated rejection (AMR) is an important factor affecting survival after renal transplantation. A highly selective proteasome inhibitor, bortezomib, clears activated plasma cells from the body and has important therapeutic effect on AMR. We investigated the effects of bortezomib on AMR in a patient after a second renal transplant. Biopsy confirmed the diagnosis of mixed cellular rejection and AMR. Bortezomib was administered on day 1 (1.3 mg/m(2)), day 4 (1.0 mg/m(2)), and day 8 (1.0 mg/m(2)). On the same days, 250 mg methylprednisolone was administered once, and cyclosporine dose (5 mg·kg(-1)·day(-1)) was reduced by 50%. Oral mycophenolate mofetil and steroid were withdrawn on day 1 of bortezomib treatment. Intermittent double-filtration plasmapheresis was also performed. We monitored parameters, including T lymphocyte subsets, CD139 and CD19 expression, panel reactive antibody (PRA), and serum creatinine concentration. At follow-up 6 months after bortezomib treatment, we observed: 1) serum creatinine stabilized at 130 μM from a peak level of 337 μM; 2) PRA decreased from a maximum of 66.7 to 0%; 3) blood plasma cell percentage rebounded after significantly decreasing following the first dose of bortezomib; 4) in renal allograft biopsy, immunohistochemical staining for C4d shifted from strongly positive to negative, and cellular rejection shifted from type IIA to borderline; and 5) adverse effects such as platelet suppression, hypotension, and grade 3 peripheral neuropathy emerged. Bortezomib effectively treated antibody-mediated renal transplantation rejection in this case study, but clinical trials with large sample sizes are still needed to explore clinical safety and tolerability.

Layered double hydroxides (LDHs) are usually synthesized by a conventional coprecipitation using inorganic salts. In this study, waste serpentine tailings (WSTs), including MgO and Fe2O3 with contents of 34 and 4.27%, were used to prepare Mg(II)Fe(III) LDHs. Firstly, WSTs were leached in a nitric acid solution at 90°C using a refluxing process in the presence of a solid∶liquid ratio of 1∶4. By a countercurrent leaching process, the acidity of the leaching solution not only was decreased but Mg and Fe were also enriched. Subsequently, waste iron was put into the leaching solution, which was used to adjust molar ratio of magnesium to ferrum. Finally, 30% NaOH solution was slowly put into the described solution to synthesize Mg(II)Fe(III)LDHs. The structure and surface morphology of the LDHs were characterized by an X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed typical structure of Mg(II)Fe(III) brucitelike sheets with exchangeable capability in an interlayer spac...

Enteric-coated mycophenolate sodium (EC-MPS) and mycophenolate mofetil (MMF), two prodrugs of mycophenolic acid (MPA), have been used in immunosuppressive regimens. After being taken orally, both of them transform to MPA to achieve immune suppression effects; however, the main site of absorption and metabolism of EC-MPS is different from that of MMF in vivo. Therefore, combined application with related drugs may result in different MPA levels and have different clinical effects in kidney transplant recipients.To evaluate the efficacy of EC-MPS compared with MMF in Chinese renal transplant patients comedicated with a proton pump inhibitor (PPI).Our subjects were 88 patients who received renal transplants at the 309th Hospital of the Chinese PLA from May 2010 to April 2013. These were made up of two groups including 27 patients with EC-MPS and 61 with MMF. The immunosuppression regimen was EC-MPS/MMF + cyclosporine/tacrolimus + steroid hormone, comedicated with a PPI (omeprazole). The patients' levels of exposure of MPA within 1 week after operation were monitored. Clinical indicators such as incidence of delayed graft function and acute rejection, the rate of change of serum creatinine hemoglobin, leucocytes, and neutrophils, as well as clinical adverse drug reactions and drug conversion were analyzed retrospectively.The kidney function of patients recovered to normal in both the EC-MPS and MMF groups. The mean concentration to peak (Cmax), the mean half-life (t1/2), and the area under the concentration-time curve (AUC0-12) of MPA in the EC-MPS group were higher than those in the MMF group (P.05). This indicated that the pharmacokinetic parameters for MPA when EC-MPS is co-administered with a PPI in kidney transplant patients in China is better than for comedication with MMF and a PPI. The MMF group had a higher incidence of drug withdrawal because of higher infection rates, leucocyte decrease, and more gastrointestinal side effects than the EC-MPS group (P.05). No significant differences in the clinical effect on kidney transplant recipients were observed in the limited observation time.

The pharmacokinetics of doxycycline was studied in plasma after a single dose (20 mg/kg) of intravenous or oral administration to tilapia (Oreochromis aureus × Oreochromis niloticus) reared in fresh water at 24 °C. Plasma samples were collected from six fish per sampling point. Doxycycline concentrations were determined by high-performance liquid chromatography with a 0.005 μg/mL limit of detection, then were subjected to noncompartmental analysis. Following oral administration, the double-peak phenomenon was observed, and the first (Cmax1 ) and second (Cmax2) peaks were 1.99 ± 0.43 μg/mL at 2.0 h and 2.27 ± 0.38 μg/mL at 24.0 h, respectively. After the intravenous injection, a Cmax2 (12.12 ± 1.97 μg/mL) was also observed, and initial concentration of 45.76 μg/mL, apparent elimination rate constant (λz) of 0.018 per h, apparent elimination half-life (t1/2λz) of 39.0 h, systemic total body clearance (Cl) of 41.28 mL/h/kg, volume of distribution (Vz) of 2323.21 mL/kg, and volume of distribution at steady-state (Vss) of 1356.69 mL/kg were determined, respectively. While after oral administration, the λz, t1/2λz, and bioavailability of doxycycline were 0.009 per h, 77.2 h, and 23.41%, respectively. It was shown that doxycycline was relatively slowly and incompletely absorbed, extensively distributed, and slowly eliminated in tilapia, in addition, doxycycline might undergo enterohepatic recycling in tilapia.

Secondary phase plays an important role in determining microstructures and properties of magnesium alloys. This paper focuses on laser-induced microstructure development and secondary phase evolution in AZ91D Mg alloy studied by SEM, TEM and EDS analyses. Compared to bulk shape and lamellar structure of the secondary phase in as-received cast material, rapid-solidified microstructures with various morphologies including nano-precipitates were observed in laser melt zone. Formation mechanisms of microstructural evolution and effect of phase development on surface properties were further discussed. ASTAR (Agency for Sci., Tech. and Research, S’pore) Accepted version

High temperature vulcanized (HTV) silicone rubber (SiR), due to its excellent electrical insulation, elasticity and temperature resistance, is used in cable accessories for HVDC cables. The space charge, generated under dc stress in SiR, would distort the local electric field, furtherly influencing the characteristics of partial discharge and accelerating the insulation aging. This paper tried to modify the space charge behaviors of HTV SiR composites by incorporating silicon carbide (SiC) particles into the polymer matrix. The effects of the SiC particle content on the field-dependent conductivity and the space charge behaviors of HTV SiR were studied. The results indicated that the conductivity of SiR/SiC composites was a nonlinear function of electric field when the content exceeds 30 wt%. With the increase of filler content, the threshold field for nonlinear conductivity decreased and the nonlinear coefficient increased. Meanwhile, the amount of space charges was dramatically reduced. It is suggested that the SiR/SiC composites with nonlinear conductivity can improve the dc conductivity under high electric field, thus suppressing the accumulation of space charge.

As an anti-inflammatory cytokine, interleukin-37 (IL-37) provides certain protective effects against inflammatory and autoimmune diseases. Recent reports indicate that IL-37 is expressed in foam cells of atherosclerotic plaques in both the coronary and carotid arteries of humans, suggesting the possible involvement of IL-37 in the pathogenesis and progression of atherosclerosis. Current evidence supports the protective role that IL-37 plays against atherosclerosis via the regulation of different subtypes of macrophage. Atherosclerosis was induced in apolipoprotein E -/- mice through diet, and the mice were then given IL-37 to observe patterns in the aorta plaque. Furthermore, human peripheral blood-derived monocytes were cultured for seven days to induce the differentiation of macrophages. Specifically, we observed the effect of IL-37 on oxygenated low density lipoprotein (ox-LDL)-induced macrophage polarity, in addition to conducting an expressional assay of the M1 cell markers tumor necrosis factor (TNF)-α and CD86 and the M2 marker CD206. IL-37 effectively decreased the area ratio between the aorta plaque and vascular cavity. We also observed that M1 macrophages can be induced from peripheral monocytes by ox-LDL, with significant elevation of marker molecules TNF-α and CD86. The co-stimulation of IL-37 and ox-LDL, however, inhibited the induction of M1 cells and facilitated the transformation of macrophages into M2 cells, as supported by the elevation of cell-specific marker CD206. These results indicate that IL-37 can prevent atherosclerosis by modulating macrophage polarity.

Fatty acid biosynthesis is essential for bacterial survival. In recent years, components of this biosynthetic pathway have aroused wide concern. β-Ketoacyl-acyl carrier protein synthase III (FabH) is a particularly attractive target which catalyzes the initial step of fatty acid biosynthesis. In this review, fatty acid biosynthesis, recent advances in the research of FabH as well as related inhibitors are reviewed. Finally, we also discuss the prospect and developmental trend of FabH inhibitors as anti-bacterial agents.

Two new zinc(II) complexes, [ZnBr2L1] (I) and [ZnBr2L2] (II), where L1 is 2-[(2-isopropylaminoethylimino)methyl]-5-methoxyphenol and L2 is N,N-dimethyl-N′-(1-pyridin-2-yl-ethylidene)ethane-1,2-diamine, were prepared and characterized using elemental analysis, FT-IR spectroscopy, and X-ray single-crystal diffraction. In complex I, the Zn(II) atom is coordinated by one phenolic O and one imino N atoms of L1 and two Br atoms, forming a tetrahedral coordination geometry. In complex II, the Zn(II) atom is in a trigonal bipyramidal coordination geometry with the equatorial plane formed by the imino N atom of L2 and two Br atoms and with the two axial positions occupied by one pyridine N and one amino N atoms of L2. In the crystal structure of I, the mononuclear zinc complex molecules are linked through intermolecular N-H…O and N-H…Br hydrogen bonds, forming chains running along the y axis. The chains are further linked via intermolecular C-H…Br hydrogen bonds. In the crystal structure of II, the mononuclear zinc complex molecules are linked through intermolecular C-H…Br hydrogen bonds, forming a 3D network.

Soil water content under no fertilizer (NF), fertilizer (F) (N:30; P 2 O 5 : 45 kg/ha), and fertilizer plus pig manure (FO) (N:30; P 2 O 5 : 45 kg/ha; pig manure 15 000 kg/ha in 2003; and 30 000 kg/ha in 2004 and 2005) treatments was measured using neutron probe instrument for a period three years in a long term field experiment in order to investi gate the impact of different fertilization treatments on Haploborolls soil water content. Fertilization had significant effects on the soil water content. FO treatment had greater soil water content in 10 cm depth than F treatment with average 9.9% increase (P < 0.05) but lower than NF treatment; however, in the depth from 30 to 90 cm, there was no water content difference between F and FO treatments. Treatment with organic amendments reduced total soil water content on the long term experiment basis. Across the three years, no fertilizer treatment had total soil water content higher by 1.2% and 3.1% than fertilizer treatment and fertilizer plus pig manure treatment within 10 to 210 cm soil profile in most of the months, respectively.

The intermediate filament (IF) synemin gene encodes three IF proteins (H 180, M 150, L 41 kDa) with overlapping distributions. Synemin M was present early with vimentin and nestin. Synemin H was found later in the nervous system and mesodermic derivatives concomitantly with angiogenesis and the migration of neural crest cells. Synemin L appeared later in neurons. A series of in vitro cell cultures were done to identify the linkage between synemin isoforms and specific cell types of the central nervous system (CNS). The neurons and glia from the brains of humans and rats were cultured and double immunostaining done with antibodies against the H/M or L synemin isoforms and neural cell types (betaIII-tubulin or NeuN) or astrocyte intermediate filaments (GFAP or vimentin). In neurons of the CNS, synemin H/M were co-expressed with GFAP, vimentin or nestin in glial cells, whereas synemin L was found in neurons.

Liquid helium (LHe) at 4.2 K was electronically excited using a corona discharge for both negative and positive high voltages. The experiments were carried out for different pressures in the range from 0.1 to 10 MPa at constant temperature. The light emitted from the zone close to the tip was spectroscopically analyzed showing features from atoms and excimer helium. The shifts and widths of the observed lines and bands were found to depend on the applied hydrostatic pressure and on the tip polarity. Our analysis showed that classic pressure broadening theory cannot account for the observed widths and shifts rather than the presence of bubbles which surround single excited atoms and molecules. For positive tip polarities red shifted features distinct from pure He and He2* were observed and tentatively assigned to "red satellites".

Based on the tunneling current model, a simplified current model is developed for MOS devices after soft breakdown (SBD). The post-soft-breakdown current consists of modified direct tunneling current and Fowler Nordheim (FN) tunneling current. Considering the change of gate oxide after soft breakdown, impacts of soft breakdown on the dielectric constant, and effective electron mass of the gate oxide are discussed, and their values are obtained by fitting simulation results to experimental data. It is found that the effective electron mass is decreased after soft breakdown due to damaged oxide, while the dielectric constant is increased after soft breakdown due to interface distortion. In this way, the leakage current after soft breakdown can be accurately calculated. The validity of the proposed model is confirmed by experimental results.

A new set of amino acid descriptors, SZOTT (Scores of Zero dimension, One dimension, Two dimension, Three dimension) was derived from principal component analysis on a matrix of 1369 descriptors including 0D, 1D, 2D and 3D information of 20 coded amino acids. SZOTT scales were then employed to represent structures of HLA-A*0201 restrictive CTL epitopes, and further, quantitative sequence-activity modelings (QSAMs) were constructed based on partial least squares and back-propagation artificial neural networks. Satisfying results show that structural information related to biological activities of HLA-A*0201 restrictive CTL epitopes can be preferably represented by SZOTT scales, which may be a useful structural representation technique for study of QSAMs of peptides.

In situ Raman spectroscopic studies, in combination with electrochemical measurements, further testify that the electrochemical reactions, i.e., iodate reduction and periodic hydrogen evolution, coupled with alternately predominant diffusion and convection mass transfer of iodate, account for the potential oscillation that appears under galvanostatic reduction of iodate over its limiting current in alkaline solution. The diffusion-limited depletion and the convection-enhanced replenishment of the iodate consist of a pair of positive and negative feedback steps between the bistable states (iodate reduction with and without hydrogen evolution). This mechanism is applicable to the same category of oscillators originating from such a coupling. The limiting diffusion concentration profile and the concentration variation of iodate in the diffusion layer during the oscillation by diffusion-limited depletion and by convection-enhanced replenishment through hydrogen evolution have been measured directly by using in situ Raman spectroscopy for the first time. A crossing cycle in the cyclic voltammogram that displays the bistability and the positive and negative feedbacks can be obtained only when the scan is reversed at a potential where hydrogen evolution takes place, and hydrogen evolution is thus mainly to induce the convection feedback of the reactant after its surface concentration depletes to zero by diffusion-limited reduction, rather than purely an additional current carrier. No oscillation can occur by simply removing the convection feedback with another pure current carrier instead of hydrogen evolution. The other model on the basis of negative differential resistance (NDR) fails to reflect the convection feedback step required for this category of oscillators.

While longer wavelength emission from InGaN/GaN light-emitting diodes can be achieved by increasing the Indium (In) content in the qunatum wells, the increased In content gives rise to side-effects to the material and device performance and reliability. It was found that the induced strain in the wafer and the density of threading dislocations increases with increasing In content. From current-voltage and 1/f noise measurements, it was observed that the leakage currents, static resistance and noise magnitudes rises monotonically with increasing emission wavelength (In composition), which can be attributed to higher defect concentrations. After undergoing a 1000-hr reliability test, it was discovered that the optical degradation rates for the longer wavelength green LEDs were significantly higher than those of shorter wavelength. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In this letter, the reliability of green InGaN-GaN light-emitting diodes (LEDs) has been analyzed by correlating the defect density of wafers with various device parameters, including leakage current, 1/f noise, and degradation rate. It was found that as the wavelength of green LEDs increases from 520 to 550 nm by increasing the indium content in the quantum wells, the defect density also increases, thus leading to larger leakage current, enhanced noise magnitude, and shortened device lifetime.

Ion implantation into Si has been used to produce near-surface, amorphous Si–N layers with the nitrogen content both below and exceeding Si3N4 stoichiometry. Iron has been introduced into some of these layers to study the effect of Fe on subsequent crystallisation to α-Si3N4. Rutherford backscattering and channeling, X-ray diffraction and cross-sectional transmission electron microscopy have been used to analyse these implanted samples before and after annealing to 1000°C. These results provide considerable insight into α-Si3N4 formed by another non-equilibrium mixing process, namely reactive ball milling or mechanochemistry.

Depending on milling conditions (air or vacuum) for the same milling time, a different level of decomposition and structure disorder in BaFe12O19 ferrite powders can be obtained by ball milling. Air-milled material has a tendency to form a gas-saturated disordered structure (superoxide) and to transform into simple oxides (reduction process through oxygen-saturated disordered phase) as opposed to the vacuum-milled powder where a highly disordered phase occurs. Both powders have a different morphology (particle size and distribution). Annealing processes produce crystalline barium ferrite phase with interesting magnetic properties, but in the present paper only structural transformations are analysed. Scanning electron microscopy, X-ray diffraction and thermal analysis techniques were applied to study the effects of heat treatment (10 h at 773 or 1273 K) in disordered BaFe12O19 ferrite powders prepared by 1000 h ball milling in air and vacuum.

Laser surface texturing based on ablation has been widely used, but hardly any reports can be found on non-ablative laser surface texturing. Silicon is highly transparent to the infrared wavelength of fiber laser (λ = 1090 nm) and thus regarded as an unsuitable tool for the purpose of surface texturing. However, we succeeded in using a continuous wave fiber laser to produce regular arrays of sub-micron bumps on silicon surface. The approach is shown to be based on laser-induced oxidation of silicon. Published version

The aim of this study was to measure the level of soluble human leukocyte antigen (sHLA-G) in renal transplant patients, to determine the relationship between these levels and the occurrence of acute rejection episodes, and to identify their influence on graft acceptance early posttransplantation. sHLA-G, as measured by an enzyme-linked immunosorbent assay, was significantly increased (P < .01) early posttransplantation (3 months); the other group maintained low levels throughout the study. The latter group displayed a high incidence of acute rejection episodes and a lower clearance of serum creatinine with a longer period for hemoglobin to recover to normal (P < .01). These results suggested that HLA-G participates in the induction of immunologic tolerance in these recipients.

International audience; The establishment of corona discharges close to a point electrode under both negative and positive high voltage in normal liquid helium (LHe) at 4.2 K is reported. The experiments were carried out at constant temperature and pressures ranging from 0.1–10 MPa. Visible luminescence emitted from the zone close to the tip revealed lines due to excited He atoms and molecules. The molecular luminescence showed hot band emissions with vibrational levels populated up to . Rotational temperatures of 800 K were estimated showing that the excitations do not thermalise. With increasing pressure the lines shifted to shorter wavelengths and became broader. The magnitude of the increase in width deviated from what is expected from the gas phase and from classical line broadening theory and rather showed similarities to the behavior of bubbles in LHe. The detailed analysis of the rotational line intensity distribution revealed the presence of an additional radiator at the long wavelength side of molecular bands that we tentatively assign to “red satellite” emission. For corona discharges with positive tip polarities both atomic and molecular lines showed “red satellite" bands with much larger intensity than for negative polarity. The origin of the red satellite and the polarity dependence is unclear yet.

The corona discharge has been realized close to point electrode under both negative and positive high voltage in normal liquid helium (LHe) at 4.2 K. The experiments have been carried out at constant temperature and for different pressures in a wide range. An intensity of the visible light emitted from the zone closed to tip was enough for its spectroscopic analysis. The shift and width of the spectra observed were measured as a function of the applied pressure. It is shown that the spectra belong to excited atoms inside of empty cavity in LHe. The significant ldquored satellitesrdquo were observed in the spectra of positive corona.

We report a Si/SiGe-based vertical-illuminated photodiode at 830 nm wavelength. Wide 3-dB bandwidth (>10 GHz), high responsivity (1.38 A/W), and high output current (2.35 mA) under avalanche operation can be achieved simultaneously without using silicon-on-insulator (SOI) substrate.

The corona discharge plasma in liquid 4He has been studied by spectroscopy as a function of the pressure between 0.1MPa and 10.4MPa. The rotational temperature was approximately equal to 350K at the pressure of 0.1MPa. With increasing pressure the blue shift and the broadening of the atomic helium line at 706.5nm (2p3P‐3s3S) and 728.1nm (2p1P‐3s1S) and the bands of the singlet d1Σu+→b1Πg transition at 639nm and triplet d3Σu+→b3Πg transition at 659nm have been observed.

Heavy metal-containing wastewater is difficult to treat by most of the bioprocess due to its toxicity to microorganism in activated sludge. In this study, a combined bioprocess consisting of biosorption section that contained magnetite immobilized Pseudomonas putida 5-x cell as biosorbent followed by sequence batch reactor (SBR) was developed to treat Cu(2+)-containing municipal wastewater. The production techniques of Pseudomonas putida 5-x cell as biosorbent, such as optimal cell harvest period and cell pretreatment techniques were studied. Experimental results showed, considering both cell biomass and cell adsorption capacity to Cu(2+), 36 h is the optimal harvest period in the course of culturing Pseudomonas putida 5-x cells as biosorbent, and 0.1-0.3 mol L(-1) HCl is an optimal cell pretreating eluant to improve Cu(2+) adsorption capacity. The performances of the combined bioprocess for treating Cu(2+) containing wastewater were assessed. Experimental results showed that after treatment by biosorption, the Cu(2+) level in wastewater was reduced to level that did not inhibit COD removal efficiency of subsequent SBR activated sludge process, although it still affected the COD adsorption capacity of activated sludge. In terms of COD removal, the biosorption section was efficient for reducing Cu(2+) concentration to provide biodegradable wastewater for subsequent SBR activated sludge process.

In the present study, an adapted bacterium PF-11 with high 1,3-dichlorobenzene degradation capability was isolated from town-gas industrial effluent through continuous introducing of N-methyl-N ′-nitro-N-nitrosoquanidine (NTG). In suitable condition, a degradation rate of 32 mg L−1d−1 of 1,3-dichlorobenzene was obtained by strain PF-11 with effective chlorion release. Strain PF-11 was tentatively identified as gram-positive Bacillus cereus. The substrate specificity of the strain PF-11 was relatively low, and the degradation rate for different chlorobenzenes was in the order of monochlorobenzene > 1,3-dichlorobenzene >1,2-dichlorobenzene. Initial oxidation step was molecular oxygen attacking chlorobenzene ring catalyzed by dioxygenase.

The In-related superfluorescence at 788 nm from Cd0.8Zn0.2Te:In single crystal has been observed and characterized by the time-resolved photoluminescence comparing with undoped Cd0.8Zn0.2Te. The peak intensity scales Nc2 and the emitted pulse width scales 1/Nc, where Nc is the coherent excited state population. The detected emission pulse shows delay of 43 ps with respect to the pump pulse and has a pulse width of 60 ps. The observation of superfluorescence from Cd0.8Zn0.2Te:In single crystal extends characteristic studies of CdZnTe as one of materials for making superfluorescence sources.

Although InGaN/GaN green light-emitting diodes (LEDs) are widely available, it is still challenging to grow green LED structures for emission at longer wavelengths due to the difficulty associated with the incorporation of In. The higher concentration of In may also affect the performance and reliability of the device. The reliability of green GaN LEDs with three different indium doping concentrations, with centre-wavelength of 520 nm, 540 nm and 550 nm, is studied in this paper. The electrical properties, including I-V characteristics, leakage current and 1/f noise were measured. The optical performance of the devices was also evaluated. The devices were subsequently subjected to a 1000 hours continuous stress test. The defect densities of the LED structures were also determined. Our results show that the 520 nm LED, which contains the lowest indium concentration in its quantum wells, produces highest optical output power at 20 mA. It also degrades slower than 540 nm and 550 nm LEDs.

While longer wavelength emission from InGaN/GaN light-emitting diodes (LEDs) can be achieved by increasing the indium (In) content in the quantum wells, the increased In content gives rise to side effects to the material and device performance and reliability. It was found that the induced strain in the wafer and the density of threading dislocations increase with increasing In content. From current-voltage and 1/f noise measurements, it was observed that the leakage currents, static resistance, and noise magnitudes rise monotonically with increasing emission wavelength (In composition), which can be attributed to higher defect concentrations. After undergoing a 1000 h reliability test, it was discovered that the optical degradation rates for the longer wavelength green LEDs were significantly higher than those of shorter wavelength.

Ability to taste phenylthiocarbamide is genetically determined and has been investigated as a possible genetic marker for disease. This study examined phenylthiocarbamide taste sensitivity in gastric and duodenal ulcer disease. The study sample included 164 patients with gastric ulcer, 134 with duodenal ulcer, and 299 community controls. Eight concentrations of phenylthiocarbamide in distilled water were obtained by binary serial dilution. The lowest concentration distinguished by taste from distilled water defined taste threshold. Bimodality of threshold distributions distinguished nontasters from tasters. Comparisons of patients with controls gave odds ratios of nontaste in gastric ulcer and duodenal ulcer of, respectively, 0.7 (P greater than 0.1) and 1.3 (P greater than 0.03). The power of detecting at least a twofold difference between patients and controls in the odds of nontaste was 80%. Nontaste was more common in duodenal than in gastric ulcer patients (odds ratio = 2.0, P = 0.02). Taste sensitivity was unassociated with other genetic factors related to ulcer--ABO blood group, secretor status, and serum pepsinogen 1 level. The difference between gastric and duodenal ulcer patients in the ability to taste phenylthiocarbamide may be genetic; however, this study's inability, despite substantial power, to detect at least a twofold difference between patients and controls suggests that if phenylthiocarbamide taste sensitivity is a genetic factor in peptic ulcer, the relationship is weak.

The hydrogen storage properties of LiBH4 ball milled with various ratios of carbon nanotubes (Cnano) were investigated. The LiBH4∕Cnano mixtures showed superior dehydrogenation, hydrogen desorption starting at 250°C, and the majority of hydrogen being released below 600°C. The rehydrogenation results revealed that the Li2C2, formed during the dehydrogenation, could be reversed to LiH, in which the hydrogen capacity corresponds to 1∕4 of the original hydrogen content of LiBH4, and C at 10MPa hydrogen pressure and 400°C.

Artemisinin (Qinghaosu), a poorly soluble sesquiterpene lactone derived from the plant Artemisia annua Linn., and a number of more soluble, semi-synthetic derivatives are rapidly-acting blood schizontocides against Plasmodium berghei and P. yoelii nigeriensis. An oily suspension of artemisinin given s.c. is more effective than aqueous suspensions. The activity is retained against lines resistant to primaquine, cycloguanil, pyrimethamine, sulphonamides, mefloquine and menoctone, but a highly chloroquine-resistant line is much less sensitive. Artemisinin has no causal prophylactic, gametocytocidal or sporontocidal action. Dihydroartemisinin causes the pigment of P. berghei to clump, but in a different fashion from the pigment changes induced by chloroquine or quinine, reflecting a different mode of action of the sesquiterpenes from that of these other antimalarials.

Striking similarities between vaccinia virus hemagglutinin (VVHA) and proteins belonging to the Ig superfamily clearly indicate that VVHA, a 315-amino acid glycoprotein expressed on the surface of the infected cells, is a novel viral protein that can be added to the expanding list of the Ig superfamily. Its deduced amino acid sequence contains one Ig-like domain at the NH2 terminus, followed by two tandem repeating units and a hydrophobic region, suggestive of membrane spanning. The results offer an opportunity for the further study of the probable evolutionary and possible functional relationship between VVHA and other members of the Ig superfamily. Our observation, together with a recent finding that human CMV possibly encodes a protein similar to the MHC class I antigens (13), provides evidence supporting the fact that the viral capture of cellular Ig-related genes is more common than expected in vaccinia and other viruses, and that usage of an Ig-like domain as recognition signals might be extended from higher animals to animal viruses.

The electric-dipole moment (edm) of the ground state of cesium has been measured using a two-laser method that does not require the presence of an external B field. The measured value ${\mathit{d}}_{\mathrm{Cs}}$=(-1.8\ifmmode\pm\else\textpm\fi{}6.7\ifmmode\pm\else\textpm\fi{}1.8)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}24}$ e cm implies that the electron EDM is ${\mathit{d}}_{\mathit{e}}$=(-1.5\ifmmode\pm\else\textpm\fi{}5.5\ifmmode\pm\else\textpm\fi{}1.5)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}26}$ e cm. This result represents more than an order-of-magnitude improvement over all previous limits.