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The micro-mechanism of hydraulic fracturing of concrete was investigated by using the discrete element method . A bonded-particle model was employed to simulate the mechanical behavior of the cement among aggregates. Coarse aggregates were modeled as unbreakable clusters composed of several particles. The initial bonded contacts is assumed to be a parallel-plate channel that is the fluid flow path, and the element of fluid is characterized by domain, which is defined as a closed chain of particles and receives flows from the surrounding channels. Hydraulic pressure applied to the particles was increasing gradually until micro-cracks were developed. The number of micro-crack caused by normal stress and shear stress were recorded during the hydraulic fracturing test. After the test was finished, the macro-crack propagation direction was obtained. The results showed that the direction of macro-crack is almost in horizontal plane and hydraulic fracturing of concrete is due to tensile cracks between aggregates.

High melting point Ni

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.

To summarize our experience in the management of stent-graft infection after endo-vascular aortic repair (EVAR) of abdominal aortic aneurysm (AAA).Data of patients who were diagnosed as endo-graft infection following EVAR and admitted in our center between January 2000 and December 2015 were reviewed. Clinical records including causes of infection, medical history, re-operative procedures, and prognostic data were analysed.A total of 10 male patients, aged 45-72 years (averaged 62.5 years), were enrolled. Two patients received previous EVAR in our center, accounting for 0.23% of all the 885 EVAR procedures we conducted during the same period. The symptoms related to stent infection, including recurrent fever (100%) and persistent back pain (40%), occured 0 to 27 months (averaged 6.9 months) after EVAR procedure. Eight patients were found to have apparent causes (80%), including 1 case with upper respiratory infection and sepsis, 4 cases with aorto-enteric fistula (AEF) and 3 cases with inflammatory AAA. Except one DNR, other 9 patients received re-operation, including 1 procedure of open debridement and drainage, 1 procedure of endo-graft excision and bilateral axillary-femoral bypass, 7 procedures of endograft excision and axillary-bifemoral bypass. During the follow-up period(2-60 months, averaged 24.1 months), 1 patient was lost, 1 patient died from aortic stump rupture (12.5%) and other 7 patients survived. Bypass occlusion was observed in 1 patient (12.5%) without severe limb ischemia.AEF and inflammatory AAA are two leading causes of endo-graft infection following EVAR in our patients. Graft excision and axillofemoral bypass is an acceptable management for this life-threatening morbidity.

To analyze the clinical features of multiple myeloma (MM) with renal insufficiency as the initial manifestation, and to improve the level of clinical diagnosis of MM, and reducing misdiagnosis of this disease.To retrospectively analyze the clinical data of 140 patients with MM, who were admitted in our Department of Nephrology and Hematology. They were diagnosed as MM by bone marrow aspiration biopsy. The patients were divided into renal insufficiency group and normal renal function group, based on the criterion of serum creatinine177 μmol/L. The two groups were statistically analyzed byt test, rank sum test,χ(2) test and binary logistic regression analysis.55.7% of the patients in the renal insufficiency group presented low level of three immunoglobulin classes (IgG, IgA, IgM), while in the normal-renal function group, 54.3% of patients mainly presented IgG subtype, showing statistically significant differences between the two groups (P0.001). Univariate analysis showed that IgM level (0.4 g/L), hemoglobin, white blood cells, erythrocyte sedimentation rate (ESR), total protein, globulin, uric acid, corrected serum calcium, proteinuria and hematuria were statistically significantly different between the two groups (P0.05 for all). Unconditional logistic regression analysis showed that lower level of IgM (OR=19.992, 95%CI: 1.327-301.202), hemoglobin, uric acid, ESR, serum total protein, proteinuria and hematuria are independent risk factors for the development of renal insufficiency in MM patients (P0.05 for all).Low level of IgM (0.4 g/L) is an important clinical characteristics of MM patients with renal insufficiency as the initial clinical manifestation. For middle-aged and elderly patients, who present as low levels of three IgG classes (IgG, IgA, IgM) or low level of IgM, multiple myeloma should be excluded, so as to reduce the misdiagnosis.

To explore the efficiency and adverse effects of the effective EP (etoposide + cisplatin) therapy and its subsequent maintenance therapy with different durations in patients with small cell lung cancer (SCLC).Clinical data of 104 SCLC patients diagnosed and treated at the Jilin Province Cancer Hospital between September 2010 and December 2013 were retrospectively analyzed.Among them, 35 patients were subsequently treated with a 4-week maintenance therapy following the original therapeutic regimen after the effective EP therapy (4-week maintenance therapy group), 35 patients were treated with a subsequent 6-week maintenance therapy (6-week maintenance therapy group), and 34 patients were treated without maintenance therapy (control group).52 patients were in limited stage, and 52 patients were in extensive stage. The progression-free survival (PFS), overall survival (OS) and adverse effects in the 4-week maintenance therapy group, 6-week maintenance therapy group and control group were analyzed.The median PFS in the control group, 4-week maintenance therapy group and 6-week maintenance therapy group was 4.0, 3.5, and 4.0 months, respectively, and the median OS was 9.0, 10.0 and 12.0 months, respectively, showing no significant difference among the groups (P0.05 for all). The median PFS was prolonged by 2 months as compared with the control group after the 4-week maintenance therapy in the patients with complete remission in first-line chemotherapy (P=0.041), while the median OS was not improved (P=0.131). Neither the median PFS nor median OS showed statistically significant difference between each two groups in the patients with partial remission in first-line chemotherapy (P0.05 for all). In the limited stage, the median PFS in the control group, 4-week maintenance therapy group, and 6-week maintenance therapy group was 5.0, 6.5, and 4.0 months, respectively, and median OS was 11.0, 13.5, and 13.0 months, respectively, the differences showed no statistical significance (P0.05 for all). In the extensive stage, the median PFS in the control group, 4-week maintenance therapy group, and 6-week maintenance therapy group was 3.0, 3.0, and 3.5 months, respectively, showing significant differences (P=0.015); the median OS was 6.5, 8.0, and 8.0 months, respectively, presenting no statistically significant differences (P=0.096). In addition, the PFS in the 6-week maintenance therapy group was significantly improved as compared with that in the control group (P=0.016). Compared with the control group, the incidence rates of nausea (grade 3-4), vomiting, hypodynamia, leukopenia, neutropenia, and thrombocytopenia in the 4-week maintenance therapy group and 6-week maintenance therapy group were increased significantly (P0.05 for all), however, the side effects were tolerable.Prolonging the treatment cycle of EP therapy can improve the PFS in SCLC patients in first-line CR chemotherapy and extensive stage.

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.

To evaluate the surgical corrective results of maxillary hypoplasia in patients with cleft lip and palate withtranspalatal modified Le Fort I osteotomy.In the study, 11 patients (4 women, and 7 men) with maxillary hypoplasia secondary to cleft lip and palate underwent transpalatal modified Le Fort I osteotomy at Peking University School of Stomatology from Jan. 2012 to Dec. 2013,with the mean age of 21 years ( from 18 to 27 years), Bilateral sagittal split ramus osteotomy (BSSRO)and genioplasty were performed simultaneously in 9 of them for better appearance and functional occlusion. Lateral cephalometric radiographs were taken and traced before surgery, immediately after surgery and 6 months after surgery. The position of subspinale (A) on horizontal direction, the angle of sella-nasion-subsipmale (SNA) and the angle of sella-nasion-supramental (SNB) were collected and analyzed to evaluate the results.All the patients were uneventful with transpalatal modified Le Fort I osteotomy. All of them had a better profile and a satisfactory occlusionafter operation.The position of A was moved forward (6.6±1.1) mm on average in horizontal direction when surgery was completed, and maintained (6.0±1.2) mm on average 6 months after surgery. The average of SNA was 75.9°±2.8° before surgery,81.6°±8.6° immediately after surgery, and maintained 81.0°±2.6° 6 months after surgery. The average of SNB was 82.6°±3.7° before surgery, 78.0°±2.4° immediately after surgery, and maintained 78.5°±2.4° 6 months after surgery.The maxillary hypoplasia in cleft lip and palate patients can be successfully corrected with transpalatal modified Le Fort I osteotomy and the functional occlusion can be achieved simultaneously. The effect of deformity correction was satisfactory. Transpalatal modified Le Fort I osteotomy can move maxilla more sufficiently, especially applicable for the patient with severe palatal scars preoperatively.

To quantitatively analyze the changes of facial symmetry and temporomandibular joint structure at different periods after intraoral condylectomy combined with orthognathic surgery, and to evaluate the long-term stability after the operation.Spiral CT data of 10 cases treated by intraoral condylectomy combined with orthognathic surgery were collected, and then reconstructed by ProPlan software. Mark points were drawn on the 3D-images reconstructed immediately after the operation, and 6 months and 12 months after the operation. The measurements parameters included condylar axis angle in three dimensions, condylar-glenoid relative position and condylar facial morphology related indicators. The results were statistically analyzed by the consistency test and the variance of repeated measurement data.The facial asymmetry of the patients was corrected after operation, the height of the affected mandibular ascending ramus(T1: [67.81±6.95]mm, T2: [64.49±6.24]mm, T3: [63.05±7.07]mm)as well as the degree of pogonion deviation decreased(T1: [2.79±4.93]mm, T2: [0.37±4.20]mm, T3: [0.33 ± 3.97]mm)(P0.05). But the tilt angle of the occlusion plane and the degree of mandibular height asymmetry had no significant difference between all the post-operative periods(P0.05). The post-operative 3D changes of the position and shape of the resected and its contralateral condylar showed that the bilateral condylar axis angle in the horizontal plane gradually grew after operation(affected condyle: 71.95° ± 7.47°, 74.73°±8.44°, 76.56°±5.22°; control condyle: 72.60°±5.56°, 76.00°±5.30°, 77.19°±6.20° and had significant difference between all the post-operative periods)(P0.05), the condyle moved slowly upward on both sides(superior space on the affected side: [8.78±4.38]mm, [4.11±2.49]mm, [3.27±1.96]mm; on the control side: [3.63±1.49]mm, [2.52±1.19]mm, [2.38±1.11]mm)(P0.05), and moved inward only on the affected side(P0.05). All the above changes slowed down over time, and the disc-condyle-fossa relative position tended to be stable over time as well. The condyle diameter on the inside-outside direction gradually decreased on the affected side(T1: [14.98±2.39]mm, T2: [14.04±2.68]mm, T3: [13.74±2.89]mm)(P0.05), and the surface morphology of the resected condyle was similar to the normal side. There were also some condylar surface morphological changes on the control side, but no statistical significance was found between different periods after the peration(P0.05).The intraoral condylectomy combined with orthognathic surgery can eliminate condylar lesions effectively and correct the facial asymmetry caused by condylar benign tumor and hyperplasia. The facial symmetry can be maintained well after the operation, and the post-operative condylar morphology changes tended to be stable six months after the operation.

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 solidification microstructure plays a critical role in determining the surface properties of laser-treated magnesium alloys. The purpose of this paper is to study the solidification microstructures of AZ91D Mg alloy following millisecond- and nanosecond-pulse Nd:YAG laser irradiation. The solidification microstructural evolution of laser-melt AZ91D Mg alloy was investigated using X-ray diffractometry, scanning electron microscopy, energy-dispersive X-ray spectrometer and transmission electron microscopy. Much refined α-Mg phase and β-Mg17Al12 intermetallics were observed in the microstructure after laser surface melting. Periodic and successive structure was observed in the millisecond irradiated surface and the melt depth was more than 100 μm. The solidification microstructure was mainly cellular/dendrite structures together with a large number of β-Mg17Al12 nano-particles. Micron holes were found in the nanosecond irradiated surface and the melt depth was shallow at 50 μm. Millisecond-pulse Nd:YAG laser was found to be more suitable for Mg alloy surface treatment due to sufficient melt depth.

Some recent research in laser-induced surface ripple structures, surface ablation, surface colouration, and their potential industrial applications are discussed in this article. Both wavelength and sub-wavelength periodic surface structures were observed on semiconductors such as InP and GaN/sapphire surfaces after irradiation of femtosecond laser pulses. The orientation of the periodic structures was dependant on the laser beam polarization, and the period was dependent on the incident laser fluence. Such surface periodic structures may find applications in controlling surface hydrophobic and hydrophilic properties. Excimer laser ablation of epoxy compounds from wafer level chip size packages was found to be a feasible method to expose the micron-size Au bumps for solder reflow, which is a critical process in manufacturing portable electronic products. Studies on controlled surface oxidation by laser pulses showed that a range of colours can be achieved on a stainless steel surface. Selective Cr oxidation and iron oxides were detected. The appearance of colour is the result of the light constructive interference of the transparent oxide layer and is determined by the oxide thickness and the refractive index. The potential industrial applications of the techniques are discussed.

The growing use of carbon-fibre-reinforced polymer (CFRP) composites as high-performance lightweight materials in aerospace and automotive industries demands efficient and low-cost machining technologies. The use of laser machining for cutting and drilling composites is attractive owing to its high speed, flexibility, and ease of automation. However, the anisotropic material properties of composites, and issues related to the heat-affected zone (HAZ), charring, and potential delamination during laser processing, are major obstacles in its industrial applications. In order to improve the quality and dimensional accuracy of CFRP laser machining, it is important to understand the mechanism of the transient thermal behaviour and its effect on material removal. Based on the ‘element death’ technique of the finite element (FE) method, a three-dimensional model for simulating the transient temperature field and subsequent material removal has been developed, for the first time, on a heterogeneous fibre—matrix mesh. In addition to the transient temperature field, the model also predicts the dimensions of the HAZ during the laser machining process. Experimental results obtained with same process variables using a 355 nm DPSS Nd:YVO4 laser were used to validate the model. Based on the investigation, the mechanism of material removal in laser composite machining is proposed. The results suggest that the employed FE approach can be used to simulate pulsed laser cutting of fibre-reinforced polymer composites.

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".

This paper addresses the cross-calibration of the infrared channels 4 (3.9 µm), 9 (10.8 µm) and 10 (12.0 µm) of the Spinning Enhanced Visible and Infra-Red Imager (SEVIRI) onboard the Meteosat Second Generation 1 (MSG1) satellite with the channels of the MODerate resolution Imaging Spectroradiometer (MODIS) onboard Terra. The cross-calibrations, including the Ray-Matching (RM) method and the Radiative Transfer Modelling (RTM) method, were developed and implemented over a tropical area using SEVIRI and MODIS measurements of July 2005 and July 2006 with absolute view zenith angle differences (|ΔVZA|)

Inhibiting gene expression in specific tissues and organs through intravenous injection would be the ultimately preferred method of disease therapy. Here, we report the successful delivery of lentivirus-mediated small interfering RNA (siRNA) to suppress GFP gene expression in living mice. First, a lentiviral vector with siRNA (len-siRNA) driven by H1 promoter was constructed to effectively suppress GFP expression in Mel cells. When the len-siRNA virus was injected into transgenic mice, the GFP expression was significantly suppressed (over 15% reduction) in the recipient mice compared to the control mice and the suppressing effect lasted more than 1 week after injection. Our results demonstrate a new effective approach to inhibit gene expression by siRNA and lentiviral vectors. Further development of this drug for suppression of gene expression siRNA should result in applications not only for cancers but also for infectious and immune diseases.

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.

This letter addresses the land surface temperature (LST) estimation from the data acquired by the spinning enhanced visible and infra-red imager (SEVIRI) on board the first geostationary satellite meteosat second generation (MSG1) using the generalized split-window algorithm proposed by Wan and Dozier (1996). The generalized split-window algorithm was developed for eight view zenith angles (VZAs) by dividing the LST, the average emissivity (e) and the column water vapour (W) into several sub-ranges to improve the LST estimating accuracy. The simulated results show that the root mean square errors (RMSEs) increase with VZAs and W, and they are less than 1.0 K for all sub-ranges with the VZA less than 45°, or for the sub-ranges with VZA less than 60° and W less than 3.5 cm. The land surface emissivities (LSEs) and W used in the generalized split-window algorithm were estimated from MSG1-SEVIRI data by the method developed by us in previous studies. The results at the four specific locations show that the LSEs were well derived, and the LSTs estimated from MSG1-SEVIRI data are basically consistent with the ones extracted from MODIS/Terra LST products.

This paper presents a rational method for estimating the maximum discharge of a landslide-induced debris flow. The method has five basic principles or steps: (a) to identify and measure representative bends and straight zones along a channel through which a debris flow went down; (b) to evaluate peak debris flow velocity in the bends; (c) to assess peak debris flow velocity in the straight channel zones; (d) to use the peak velocities to estimate the distribution of peak discharge along the entire channel; and (e) to find the maximum velocity and discharge of the debris flow. The method is illustrated with a case study of a landslide-induced debris flow at a mountainous region near Chengdu, southwestern China. The results show that the peak debris velocity was between 2.4 and 4.7 m s(-1) and the peak debris discharge was between 6.7 and 35.7 m(3) s(-1). The peak discharge initially increased at the upper portion of the channel, then decreased at the lower portion, indicating that the upper channel experienced erosion but the lower channel experienced deposition. The location with the maximum debris flow discharge corresponds to the point where the volume of the debris flow started to decrease. The method presented in this paper can help to prevent or mitigate debris flow hazards. (c) 2006 Elsevier B.V. All rights reserved.

A time-domain discontinuous Galerkin method is presented to analyze transient scattering from perfect electrically conducting (PEC) objects. As mono-polar RWG functions are chosen for spatial functions, it is possible to analyze complex structures with either conformai or non-conformal discretization. Numerical results are included to demonstrate the accuracy and efficiency of this method.

The momentum signatures in nonperturbative multiphoton pair production for general elliptic polarization electric fields are investigated by employing the real-time Dirac-Heisenberg-Wigner formalism. For a linearly polarized electric field we find that the positions of the nodes in momenta spectra of created pairs depend only on the electric field frequency. The polarization of external fields could not only change the node structures or even make the nodes disappear but also change the thresholds of pair production. The momentum signatures associated to the node positions in which the even-number-photon pair creation process is forbid could be used to distinguish the orbital angular momentum of created pairs on the momenta spectra. These distinguishable momentum signatures could be relevant for providing the output information of created particles and also the input information of ultrashort laser pulses., 8 pages, 4 figures, submitted to Europhysics Letters

We report two methods of fabricating waveguides in photosensitive Ag+ doped Foturan glass by femtosecond laser writing and subsequent annealing. The first method involves writing at laser energies higher than the optical breakdown threshold, directly resulting in microstructural changes and a refractive index increase. In contrast, the laser energy used in the second method was much lower than the threshold for optical breakdown. Subsequent thermal annealing at 500 °C after this writing process causes Ag nanoparticles to precipitate in the laser written trace and a corresponding increase in the refractive index. The effect of Ag nanoparticles population on the guiding characteristics of the written waveguides is addressed. We found that there is an optimum population of Ag nanoparticles in a waveguide. Propagation losses increase at above this population level due to high absorption/scattering, while a population level below the optimum is indicative of minimal index change and hence providing poor confin...

Two image-processing techniques are developed to measure precisely the positions of Jupiter and its Galilean satellites. One is used to detect the edge of Jupiter's CCD image and fit it with an ellipse, thereby obtaining the planetary center. The other is used to remove the positional effect of Jupiter's scattering light that has on the measurement of a close satellite. 133 frames of CCD images are measured by using these techniques, and these measured positions of Galilean satellites are compared to the ones computed with the ephemerides of Jacobson's JUP204 and Arlot's G5. Preliminary analysis of the data as Jupiter-satellite or inter-satellite positions shows that a standard error (i.e. internal precision) as small as 0.03 arcsec can be reached in right ascension and declination. It is believed that these techniques would be useful for astrometric and photometric CCD observations of Galilean satellites, especially for CCD observations in the forthcoming mutual phenomena of Galilean satellites.

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.

Teak (Tectona grandis Linn. f.), belonging to Lamiaceae, is one of the most precious timber species. In May 2015, a severe canker was found on stems of teak saplings in an orchard in Pubei County, Guangxi Province, China. Twenty-seven percent of saplings (about 7 cm diameter at 1.4 m height) were infected in this site (2 hectares) and the disease was also found in four otherorchards in Guangxi. The bark of infected stems first turned brown, then became gray followed by cracking. As lesions expanded, sunken cankers appeared and eventually the tree died. Stems of diseased plants took a red color. On potato dextrose agar (PDA), a fungus was isolated from 92% of 25 samples collected on the stem of three cankered saplings. Samples were surface sterilized in 75% ethanol for 30 s and then in 2.5% sodium hypochlorite for 2.5 min. The colonies on PDA showed sparse white mycelium. Microconidia, produced 7 days after incubation (DAI) at 25 °C on PDA, were oval, ellipsoid, reniform, fusiform and aseptate, 5.12 to 12....

Micro-structured InGaN light-emitting diodes (µLED) are capable of delivering enhanced light output due to additional light extraction through exposed sidewalls. However, these sidewalls formed by plasma etching can potentially affect the lifetime and reliability of the devices as a result of plama damage. A study on the electrical characteristics and reliability of µLED arrays has been carried out in this work. Although improved optical performance can be expected based on previous studies, expanded device sidewalls prove to accelerate the rate of optical degradation, adversely affect the lifetimes of devices. Through precise current-voltage measurement vertical current conduction along the plasma-damaged sidewalls was identified as the key mechanism contributing to degraded reliability. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The pan-tropical genus Ardisia has more than 400 species and is of high horticultural and medicinal value. Due to overexploitation it is important to conserve the germplasm of this genus.To investigate the feasibility and methods of cryopreservation for long-term seed storage of three Ardisia species: A. elliptica Thunb., A. brunnescens Walker, and A. virens Kurz.We tested whether rapid desiccation can increase desiccation tolerance and cryotolerance, and whether the thawing rate can affect cryopreservation success. Seeds were subjected to three desiccation treatments: 1) activated silica gel at 25 +/- 2 degree C, and 4% relative humidity (RH); 2) saturated NaCl solution in closed jars in 25 +/- 2 degree C and 75% RH; and 3) air-drying at room conditions at 27 +/- 2 degree C and RH 60% for different desiccation durations (12h, 24h, 48h, 96h, and 196h). Seeds were then assessed for desiccation tolerance and cryotolerance after rapid thawing (direct immersion in 36 degree C water bath for 2 min) or slow thawing (at 27°C for 1 h).For all three species, desiccation method and duration significantly affected cryotolerance (P0.0001). Fast desiccation did not improve germination compared to slower desiccation (P0.01). Whereas A. elliptica germination was unaffected by desiccation duration, drying time significantly (P0.0001) affected germination percentage in the other two species especially after 48h. Although slow thawing improved cryotolerance of A. brunnescens seeds (P0.05), there was no significant effect of thawing rate on A. elliptica. A. virens seed did not survive cryopreservation.Cryopreservation protocols of Ardisia species may be species-specific and should be established for each species in the genus so that cryopreservation can be used as a successful conservation strategy.

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.

There are suggestions that duodenal ulcer protects individuals from gastric cancer and that rice is ulcerogenic while wheat is gastro-protective. We aimed to examine the relationship of gastric cancer, duodenal and gastric ulcers in different geographical regions in China and identified dietary risk factors for duodenal ulcer and gastric cancer. The prevalence of peptic ulcer and gastric cancer among symptomatic patients in eight major cities, four each from the north and the south representing all the six defined regions of China were studied. Endoscopy and case records over a 10 year period were reviewed and cases of confirmed duodenal and gastric ulcer and gastric cancer, together with the total number of endoscopies performed per year, were recorded. Rates were expressed as cases/1000 endoscopies. Results were compared to another epidemiological study on diet and mortality in the same regions in China conducted at the same time. Duodenal ulcer rates were 2.4-fold higher in southern China than northern China, whereas gastric cancer rates were 1.6-fold higher in the north than in the south. Correlation studies showed for the first time an inverse linear relationship between the gastric cancer rates and the duodenal ulcer rates (r=-0.8076, P=0.015), as well as the duodenal ulcer: gastric ulcer ratios (r=-0.9133, P=0.002). Gastric ulcer rates were higher in southern China but did not correlate with the gastric cancer rates (r=0.1455, P=0.731). Duodenal ulcer rates were found to be related to daily rice intake (r=0.8554, P=0.029) and inversely related to daily wheat flour intake (r=-0.8472, P=0.033). Gastric cancer rates were not related to any dietary risk factors tested. We concluded there was an inverse relationship between gastric cancer rates and duodenal ulcer rates. Although duodenal ulceration and gastric cancer are both linked to Helicobacter pylori infection, the findings of this study indicate independent additional aetiological factors for the pathogenesis of these conditions. Dietary factors such as rice or wheat intake may play a role.

Background and study aims After the first gastroscopic removal of a bezoar by McKechne in 1972, different endoscopic methods have been reported including a water jet, forceps, snare, and basket. Huge and solid bezoars, however, are still a problem. We report on our experience in fragmenting huge, solid bezoars using a modified needle-knife (bezotome) and a modified mechanical lithotriptor (bezotriptor). Patients and methods Over a period of 14 months (October 1994 to December 1995), a total of 15 patients (ten male, five female, median age 41 years) with 17 gastric bezoars and one esophageal bezoar, treated endoscopically, were included in the study. A monopolar diathermy knife with a 15 mm needle (bezotome) was used for trichobezoars. For diospyrobezoars we need a bezotriptor. Results All 18 bezoars, from 4 x 3 x 3 cm to 10 x 8 x 8 cm in size, were successfully fragmented, ten in one session and eight in two sessions. Complete clearance of the upper digestive tract was achieved at the latest three days after the treatment. There were no complications. Conclusions Bezotome and bezotriptor are useful endoscopic devices to disintegrate huge, hard bezoars and achieve complete clearance.

The extracellular signal-regulated kinase (ERK) is one of the three major types of mitogen-activated protein kinases. Previous studies showed that ERKs mediate various signaling pathways for cell proliferation, differentiation, survival and transformation in mammals. In the present study, we use goldfish as a model system and demonstrate that ERK kinases play important roles in promoting embryonic survival and regulate development of eye and trunk in vertebrates. ERKs are highly expressed in multiple tissues including lens epithelial cells, lens fiber cells, retina, brain, muscle and heart of adult goldfish. Injection of the dominant negative ERK mutant (DNM-ERK) into the fertilized eggs of goldfish significantly inhibited ERK activity at blastula stage, and completely blocked ERK activity at gastrula and later stages. As a result, the blastula cells were induced into apoptosis, and majority of the injected embryos were lethal at embryonic stages. At the molecular level, inhibition of ERK activity by DNM-ERKs suppressed phosphorylation of Bad at Ser-112 to promote apoptosis. Similar results were observed when MEK activity was inhibited by U0126 treatment. The survived embryos display significant abnormality in the phenotypes of both eye and trunk. Associated with the abnormality in the eye development, phosphorylation in Pax-6 and expression of HSF4 were significantly decreased and expression of the β-crystallin gene was also downregulated. These results provide novel information regarding the roles of ERKs in regulating vertebrate development.

Periodic solutions and global stability of Hopfield neural networks with variable delays are investigated. Sufficent conditions are given for the existence of periodic solutions and for the global stability

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.

We demonstrate an integration of polymer light-emitting diode (LED) and polymer transistor in which no patterning of the organic layers is needed. Intrinsic high-mobility semiconducting conjugated polymer poly(3-hexylthiophene)(P3HT) is used as the hole-transport layer for polymer LED. The light emission efficiency is only slightly lower than the LED with conventional heavily doped hole-transport layer. Such LED is easily integrated with a P3HT transistor without patterning.

LUCC (Land use and land cover change) is increasingly regarded as an important component of global environmental change and sustainable development. In this study, regional land cover type maps were drawn using the MODIS products from 2001 and 2010 based on the modified classification scheme embodied by the characteristics of land cover in Yunnan. Dynamic change in each type of land cover was investigated by classification statistics, dynamic transfer matrices, and landscape pattern metrics. In addition, the driving factors of LUCC were discussed. The results showed that the land cover types of the Yunnan province, especially woodland (WL), cropland (CL) and grassland (GL), had experienced noticeable changes with an area of about 30% of land during the study period. And there was an obvious vertical distribution pattern for land cover types. The average altitude of different land cover types from the highest to the lowest were unused land (UUT), WL, GL, water (WT), urban and built-up areas (UB) and CL. The average slope for most of the land-cover types did not vary over the past 10 years. Stabilization and homogenization will be the direction of land cover in the future according to landscape metrics analysis. The regional differences of land use structure in the area are strongly influenced by such factors as the geographical position, level of economic development and land use policy. The new policy of land use, Construction of Mountainous Town, would be provided to achieve the economical and intensive utilization of land resources during the rapid development of urbanization and industrialization in Yunnan.

The c-Jun N-terminal kinases (JNKs) constitute one of the three major types of mitogen-activated protein kinases. Previous studies showed that JNK mediates multiple signaling transduction pathways implicated in cell proliferation, differentiation, inflammation, stress response and apoptosis in mammals. In the present study, we use goldfish as a model system and demonstrate that JNK kinases are necessary to promote embryonic survival and regulate eye development in vertebrates. During goldfish development, JNK1 and JNK2 are expressed at every stage from cleavage to hatching larvae. JNK3 is turned on at the gastrulation stage and then expressed at similar level to that of JNK2. JNK1 activity remains slightly fluctuated during different developmental stages. Inhibition of JNK activity caused massive apoptosis of blastula cells and significant death of goldfish embryos, which are associated with altered expression of the anti-apoptotic regulator, Mcl-1 and the proapoptotic regulator, Bak. These results provide novel information regarding the mechanisms by which JNKs promote embryonic survival. In addition, the embryos that survived inhibition of JNK activity displayed severe phenotype in the eye with clear microphthalmia and lens coloboma. To confirm that the observed phenotype is derived from JNK activity deficiency, we expressed JNK dominant negative mutant (DNM-JNK) in goldfish. Expression of DNM-JNK also caused similar phenotypes with altered expression of pax-6, Sox-2 and β-crystallin. Together, our results demonstrate that JNKs play important roles in promoting survival of vertebrate embryos and regulating development of vertebrate eye.