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In order to elucidate pressure-induced second superconducting phase (SC-II) in AxFe2−ySe2 (A = K, Rb, Cs, and Tl) having an intrinsic phase separation, we perform a detailed highpressure magnetotransport study on the isoelectronic, phase-pure (Li1−xFex)OHFe1−ySe single crystals. Here we show that its ambient-pressure superconducting phase (SC-I) with a critical temperature Tc ≈ 40 K is suppressed gradually to below 2 K and an SC-II phase emerges above Pc ≈ 5 GPa with Tc increasing progressively to above 50 K up to 12.5 GPa. Our high-precision resistivity data uncover a sharp transition of the normal state from Fermi liquid for SC-I to non-Fermi liquid for SC-II phase. In addition, the reemergence of high-Tc SC-II is found to accompany with a concurrent enhancement of electron carrier density. Without structural transition below 10 GPa, the observed SC-II with enhanced carrier density should be ascribed to an electronic origin presumably associated with pressure-induced Fermi surface reconstruction. [ABSTRACT FROM AUTHOR]

The phase transition performance of the CaCl2 · 6H2O-Ca(NO3)2 · 4H2O composite salt system with nucleating and thickening agents was investigated in this paper. The CaCl2 · 6H2O-Ca(NO3)2 · 4H2O composite salt system was prepared by adding Ca(NO3)2 · 4H2O (12 wt%) to CaCl2 · 6H2O. Different nucleating agents including SrCl2 · 6H2O, SrCO3, BaCl2, BaCO3, Na2B4O7 · 10H2O, H3BO3 and NH4Cl were used to address the problems of phase segregation and supercooling phenomena during the phase change process. The results show that the single nucleating agent SrCl2 · 6H2O or the mixture of nucleating agents with 2 wt% SrCl2 · 6H2O, 1 wt% BaCl2 and 0.5 wt% of thickening agent carboxyl methyl cellulose is the most suitable for this system. The latent heat remained constant at about 116 J/g before and after adding the agents. Density functional theory was used to further investigate the microstructure-related reason for the salt-water separation and supercooling phenomena. It can be deduced that the hydrogen bond is the vital factor involved during the phase transition. The aim of adding thickener was to form more hydrogen bonds which encapsulated the hydrated species and made it difficult to lose the hydrated waters. The main purpose of adding nucleating agent was to break the metastable state among microscopic species. The results of this work indicate that the CaCl2 · 6H2O-Ca(NO3)2 · 4H2O salt mixture has potential as a thermal energy storage material. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Floral nectar can affect the fitness of insect-pollinated plants, through both attraction and manipulation of pollinators. Self-incompatible insect-pollinated plants receive more insect visits than their self-compatible relatives, and the nectar of such species might face increased risk of infestation by pathogens carried by pollinators than self-compatible plants. Proteins in nectar (nectarins) play an important role in protecting the nectar, but little is known regarding nectarins in self-incompatible species., The nectarins from a self-incompatible and insect-pollinated leguminous crop, Canavalia gladiata, were separated using two-dimensional electrophoresis and analysed using mass spectrometry. The predominant nectarin gene was cloned and the gene expression pattern investigated using quantitative real-time PCR. Chitinolytic activity in the nectar was tested with different substrates., The C. gladiata nectar proteome only has one predominant nectarin, an acidic class III chitinase (CaChi3). The full-length CaChi3 gene was cloned, coding for a protein of 298 amino acids with a predicted signal peptide. CaChi3 is very similar to members of the class III chitinase family, whose evolution is dominated by purifying selection. CaChi3 was expressed in both nectary and leaves. CaChi3 has thermostable chitinolytic activity according to glycol-chitin zymography or a fluorogenic substratem but has no lysozyme activity., Chitinase might be a critical protein component in nectar. The extremely simple nectar proteome in C. gladiata disproves the hypothesis that self-incompatible species always have more complex nectar proteomes. Accessibility of nectar might be a significant determinant of the evolutionary pressure to develop nectar defence mechanisms. [ABSTRACT FROM AUTHOR]

Electrochemical micromachining has good application potential for processing of materials. The size of microtool poles is the key in electrochemical micromachining, which directly affects the size and accuracy of processed elements. To minimise the size of tool poles, we proposed a micromachining technique in which a tungsten wire was etched in two steps and the diameter of 1 μm was achieved successfully. The effect of solution concentration on the current-voltage relationship during processing of tungsten wire was investigated, and the proper solution concentration was determined. The effect of voltage applied between two electrodes on the quality of tungsten wire pole was examined, and the applied voltage was optimised. Moreover, the changes of tungsten wire diameter with time and current were studied, and thus a microtungsten wire pole with a given diameter can be produced easily. [ABSTRACT FROM AUTHOR]

Ni0·25-xMgxCu0·3Zn0·45Fe2O4 (for x = 0, 0·05, 0·1, 0·2 and 0·25) ferrites have been synthesised by NaOH coprecipitation method. The X-ray diffraction patterns of these ferrites confirmed the formation of the single phase spinel structure. The lattice constant was found to increase with Mg content obeying Vegard's law. The crystallite size of these samples varies from 13·2 to 16·4 nm. The bulk density ρB decreases with increasing Mg concentration. And scanning electron microscopy images show no obvious differences among all samples with different Mg concentration. With increasing Mg content, the initial permeability monotonously increases while the cutoff frequency fr gradually decreases, which agrees well with Snoek's law. Moreover, saturation magnetisation Ms and the Curie temperature Tc continuously decrease with increasing Mg content but no noticeable variation in quality factor Q with Mg content is observed. [ABSTRACT FROM AUTHOR]

The inter/extrapolation accuracy of the cubic polynomial method has been improved by optimizing three frequency samples for frequency-sweeping in the method of moments (MoM). In the method, the frequency samples are optimized by minimizing the global maximum of the polynomial component at the stationary points and two terminal points of the frequency band. The optimal frequency samples can be expressed as analytical forms of the two terminal points. Numerical examples are presented to validate the proposed method through comparison with the Padé approximation. [ABSTRACT FROM AUTHOR]

The effects of compatibiliser molecular weight, temperature of the first mixing zone of the extruder and nanoclay loading on the mechanical and thermal properties of polymer-clay nanocomposites (PCNs) were investigated. It was found that the molecular weight of the compatibiliser, the temperature of the first mixing zone of the extruder and the nanoclay content have significant effects on the mechanical and thermal properties of the polyethylene-clay nanocomposites. The blending of the high and low molecular weight compatibilisers allowed a more efficient interface between the nanoclay and the polymer matrix. Coupling a more efficient bonding with the high shear in the first mixing zone of the extruder at a low temperature produced an intercalated/exfoliated nanoclay filler resulting in enhanced mechanical properties of the PCNs. [ABSTRACT FROM AUTHOR]

Allogeneic pancreatic islet transplantation theoretically represents a cure for type 1 diabetes. However, current immune suppressive therapies are often associated with undesired side effects. Given this problem, and the shortage of human islet donors, the majority of type 1 diabetes patients cannot currently be offered an islet transplant. However, it has been found that mesenchymal stem cells (MSCs) could exert unique immunosuppressive effects both in vitro and in vivo. Herein we transplanted allogeneic 200 islets alone or in combination with MSCs (3 × 106 cells) under the kidney capsules of diabetic C57LB/6 mouse. We found that the ratios of T helper type 1 (Th1) to Th2 and Tc1 to Tc2 were reduced, and the numbers of naive and memory T cells were down-regulated in peripheral blood after transplantation. In addition, the maturation, endocytosis and interleukin-12 secretion of dendritic cell (DCs)-derived bone marrow cells (BMCs) from receptor mice were suppressed. Rejection reaction was alleviated by MSCs which exerted suppressive effects through T lymphocyte subsets and DCs. [ABSTRACT FROM AUTHOR]

This article investigates the principal screws and their pitches of screw systems from the viewpoint of line geometry. It starts fromthe fact that any n-independent screws pertaining to a specified n-screw system can be utilized to determine the system, and the pitch of a unit screw is the half of the reciprocal product with itself. The reciprocal product matrix of a screw matrix is therefore defined to determine the principal pitches and the directions of the principal screw axes of the system. With matrix diagonalization procedure, one can immediately obtain the principal pitches and the principal screws of a screw system. The whole procedure is straightforward and easily understood by an engineer with primary knowledge of linear algebra. Besides, the computational effort is greatly reduced and the efficiency is better compared with other methods. As a matter of fact, the pitch of any screw of a screw system can be represented by a homogeneous quadratic form of the linear combination coefficients. The homogeneous quadratic equation of the pitch of a screw system represents a conic curve in a two-system and an ellipsoid or a hyperboloid in a three-system. Therefore, this article also provides such visualizations of the principal axes in two- and three-dimensional spaces at last. [ABSTRACT FROM AUTHOR]

Bemisia tabaci has caused significant crop losses in China during the last decade. Recent research has shown that two potentially invasive variants, biotypes B and Q, have been found in several regions of China. Our objective was to determine the biotype status and the distribution of B. tabaci in Shandong province, an important agricultural region of China. Based on mitochondrial DNA markers, both biotypes B and Q were detected, with B being the predominant biotype. The results indicate that the more recently introduced biotype Q has not only been located in China but also has established and spread in some regions. [ABSTRACT FROM AUTHOR]

Novel single-layer planar directional couplers based on substrate integrated waveguide (SIW) technology are presented. These proposed couplers are totally realised in single-layer dielectric substrate with metallicvias, and fabricated using a standard PCB process. Prototypes of -3 dB, -6 dB and -10 dB SIW directional couplers are designed, fabricated and measured. It is concluded from the simulated and measured results that these couplers show good performances with broad operation bandwidth, low insertion loss, low return loss and high isolation etc. The characteristics of compact size and planar form make such SIW directional couplers can be easily integrated in microwave and millimetre-wave planar circuits. [ABSTRACT FROM AUTHOR]

Epidermal growth factor receptor (EGFR) had been reported as one of the major responsible genes for malignant progression and phenotype reversion of gliomas, and has been used as one of the most important therapeutic targets. In the present study, small interference RNA (siRNA) and antisense EGFR expression constructs, which target sequences of human EGFR catalytic domain (2400–2420) and the 3′-coding region, respectively, were used to examine the growth inhibition effects on U251 glioma cells. Cell growth was significantly inhibited and G2/M arrest was observed in antisense- and siRNA-treated groups. Matrigel matrix demonstrated spotted cell clustering pattern in antisense- and siRNA-transfected U251 cells, indicating poor cell growth activities. In addition, the tumor volumes in U251 subcutaneous mice model treated with antisense and siRNA were significantly smaller than those treated with control siRNA and phosphate-buffered saline. Also, glial fibrillary acidic protein expression was upregulated in antisense- and siRNA-treated groups than the control groups. Our results demonstrated that antisense- or siRNA-targeting intracellular region of EGFR can inhibit EGFR expression, exerted growth inhibition effect on U251 glioma cells in vitro and in vivo. Consequently, siRNA expression plasmid-mediated gene therapy would be a new strategy in treatment of gliomas.Cancer Gene Therapy (2006) 13, 530–538. doi:10.1038/sj.cgt.7700932; published online 6 January 2006 [ABSTRACT FROM AUTHOR]

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