Magnetic Properties of Dilute Alloys: Equations for Magnetization and its Structural Fluctuations

The dilute Heisenberg ferromagnet is studied taking into account fluctuations of magnetization caused by disorder. A self-consistent system of equations for magnetization and its mean quadratic fluctuations is derived within the configurationally averaged two-time temperature Green's function method. This system of equations is analised at low concentration of non-magnetic impurities. Mean relative quadratic fluctuations of magnetization are revealed to be proportional to the square of concentration of impurities.Comment: 16 pages, LaTe

Effects of Rosiglitazone on the Expression of PPAR-&#947 and the Production of IL-6 and IL-8 in Acute Lung Injury Model Using Human Pulmonary Epithelial Cells

Purpose: Peroxisome proliferator-activated receptor (PPAR)-γ ligand is known to repress the expression of pro-inflammatory mediators. However, it is unclear how it affects PPAR-γ expression and the inflammatory response in the human lung. We investigated the effects of rosiglitazone (synthetic PPAR-γ ligand) on the PPAR-γ expression and on the IL-6 and IL-8 production in acute lung injury model using human lung epithelial cells.Methods: A549 and Beas-2B cells were pre-treated with rosiglitazone and/or BADGE (selective PPAR-γ antagonist) and then treated with media control or cytokine mixture including TNF-α, IL-1 β, and IFN-γ. PPAR-γ expression was analyzed in cell lysates by Western blot. IL-6 and IL-8 production was measured in the culture supernatants by ELISA.Results: PPAR-γ expression was identified in all experimental groups except for the control. The cytokine mixture-induced IL-6 and IL-8 production was significantly inhibited by pre-treatment with rosiglitazone (P<0.01). However, this inhibitory effect of rosiglitazone was not reversed by BADGE.Conclusion: These suggest that rosiglitazone induces the PPAR-γ expression and it may inhibit the cytokine mixture-induced IL-6 and IL-8 production through the PPAR-γ independent pathway. The inhibitory mechanisms of rosiglitazone on the cytokine mixture-induced IL-6 and IL-8 production in human alveolar and bronchial epithelial cells remain to be further investigated.Keywords: Rosiglitazone, PPAR-γ, IL-6, IL-8, Acute lung injur

Effects of Rosiglitazone on the Expression of PPAR-&#947 and on the Production of IL-6 and IL-8 in Acute Lung Injury Model Using Human Pulmonary Epithelial Cells

Purpose: Peroxisome proliferator-activated receptor (PPAR)-γ ligand is known to repress the expression of pro-inflammatory mediators. However, it is unclear how it affects PPAR-γ expression and the inflammatory response in the human lung. We investigated the effects of rosiglitazone (synthetic PPAR-γ ligand) on the PPAR-γ expression and on the IL-6 and IL-8 production in acute lung injury model using human lung epithelial cells.Methods: A549 and Beas-2B cells were pre-treated with rosiglitazone and/or BADGE (selective PPAR-γ antagonist) and then treated with media control or cytokine mixture including TNF-α, IL-1β, and IFN-γ. PPAR-γ expression was analyzed in cell lysates by Western blot. IL-6 and IL-8 production was measured in the culture supernatants by ELISA.Results: PPAR-γ expression was identified in all experimental groups except for the control. The cytokine mixture-induced IL-6 and IL-8 production was significantly inhibited by pre-treatment with rosiglitazone (P<0.01). However, this inhibitory effect of rosiglitazone was not reversed by BADGE. Conclusion: These suggest that rosiglitazone induces the PPAR-γ expression and it may inhibit the cytokine mixture-induced IL-6 and IL-8 production through the PPAR-γ independent pathway. The inhibitory mechanisms of rosiglitazone on the cytokine mixture-induced IL-6 and IL-8 production in human alveolar, and bronchial epithelial cells remain to be further investigated.Keywords: Rosiglitazone, PPAR-γ expression, IL-6, IL-8, Acute lung injur

Role of sea ice on satellite-observed chlorophyll-a concentration variations during spring bloom in the East/Japan sea

The relationship between the spring bloom along the Primorye coast and the sea ice of the Tatarskiy Strait in the northern region of the East/Japan Sea, a semi-enclosed marginal sea in the North Pacific, was investigated using the ten-year SeaWiFS chlorophyll-a concentration data and DMSP/SSMI sea ice concentration data from 1998 to 2007. Year-to-year variations in the chlorophyll-a concentrations in the spring were positively correlated with those of the sea ice concentrations in the Tatarskiy Strait in the previous winter with a correlation coefficient of 0.77. Abrupt increases in nutrients, essential for the spring bloom in the upper ocean during spring, were supplied from sea ice-melted waters. Time series of vertical distributions of the nutrients indicated that phosphate concentrations were extremely elevated in the upper ocean (less than 100 m) without any connection to high concentrations in the deep waters below. The water mass from sea ice provided preferable conditions for the spring bloom through changes in the vertical stratification structure of the water columns. Along-coast ratios of stability parameters between two neighboring months clearly showed the rapid progression of the generation of a shallow pycnocline due to fresh water originating from sea ice. This study addressed the importance of the physical environment for biogeochemical processes in semi-enclosed marginal seas affected by local sea ice. (C) 2013 The Authors. Published by Elsevier Ltd. All rights reserved.1166Ysciescopu

Variability study of Si nanowire FETs with different junction gradients

Random dopant fluctuation effects of gate-all-around Si nanowire field-effect transistors (FETs) are investigated in terms of different diameters and junction gradients. The nanowire FETs with smaller diameters or shorter junction gradients increase relative variations of the drain currents and the mismatch of the drain currents between source-drain and drain-source bias change in the saturation regime. Smaller diameters decreased current drivability critically compared to standard deviations of the drain currents, thus inducing greater relative variations of the drain currents. Shorter junction gradients form high potential barriers in the source-side lightly-doped extension regions at on-state, which determines the magnitude of the drain currents and fluctuates the drain currents greatly under thermionic-emission mechanism. On the other hand, longer junction gradients affect lateral field to fluctuate the drain currents greatly. These physical phenomena coincide with correlations of the variations between drain currents and electrical parameters such as threshold voltages and parasitic resistances. The nanowire FETs with relatively-larger diameters and longer junction gradients without degrading short channel characteristics are suggested to minimize the relative variations and the mismatch of the drain currents. (C) 2016 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).1163Ysciescopu

Statistical variability study of random dopant fluctuation on gate-all-around inversion-mode silicon nanowire field-effect transistors

Random dopant fluctuation effects of gate-all-around inversion-mode silicon nanowire field-effect transistors (FETs) with different diameters and extension lengths are investigated. The nanowire FETs with smaller diameter and longer extension length reduce average values and variations of subthreshold swing and drain-induced barrier lowering, thus improving short channel immunity. Relative variations of the drain currents increase as the diameter decreases because of decreased current drivability from narrower channel cross-sections. Absolute variations of the drain currents decrease critically as the extension length increases due to decreasing the number of arsenic dopants penetrating into the channel region. To understand variability origins of the drain currents, variations of source/drain series resistance and low-field mobility are investigated. All these two parameters affect the variations of the drain currents concurrently. The nanowire FETs having extension lengths sufficient to prevent dopant penetration into the channel regions and maintaining relatively large cross-sections are suggested to achieve suitable short channel immunity and small variations of the drain currents. (C) 2015 AIP Publishing LLC.open111415sciescopu

High efficiency silicon solar cell based on asymmetric nanowire

Improving the efficiency of solar cells through novel materials and devices is critical to realize the full potential of solar energy to meet the growing worldwide energy demands. We present here a highly efficient radial p-n junction silicon solar cell using an asymmetric nanowire structure with a shorter bottom core diameter than at the top. A maximum short circuit current density of 27.5 mA/ cm(2) and an efficiency of 7.53% were realized without anti-reflection coating. Changing the silicon nanowire (SiNW) structure from conventional symmetric to asymmetric nature improves the efficiency due to increased short circuit current density. From numerical simulation and measurement of the optical characteristics, the total reflection on the sidewalls is seen to increase the light trapping path and charge carrier generation in the radial junction of the asymmetric SiNW, yielding high external quantum efficiency and short circuit current density. The proposed asymmetric structure has great potential to effectively improve the efficiency of the SiNW solar cells.111918Ysciescopu

Molecular and genetic characterization of OSH6 (Oryza sativa Homeobox 6) using dissociation (Ds) insertion mutant rice

Genetic studies of dissociation (Ds) insertion mutant rice plants indicated that ectopic expression of truncated OSH6 (Oryza sativa Homeobox 6) mRNA may be responsible for the mutant phenotype of knotted leaf formation at the peduncle. Additionally, ectopic expression of truncated OSH6 mRNA in the OSH6-Ds mutant plant led to alteration of other homeobox genes including OSH15 in leaf tissues. The OSH6-Ds mutant plant exhibited altered expression of more than 118 genes on a 22K rice microarray in comparison with wild type plants. Of these genes, 20 were up- or down-regulated in both OSH6-Ds and OSH6-overexpressing (OSH6-35S) plants. Especially, OsDof3 was not expressed in floral organs, but was present in the panicles of both OSH6-Ds and OSH6-35S plants. It is assumed that truncated OSH6 transcript might be actively involved in the gene expression during organ development. The genetic relationship between OSH6-Ds and OSH15 suggested that the formation of the extra leaf is independent of OSH6-Ds or OSH15 expression. These results suggest that truncated OSH6 mRNA influences lateral organ growth and development by regulating the expression of specific gene groups.Key words: Oryza sativa Homeobox 6 (OSH6) genes, Ds insertion lines, OSH15 mutant

The Stokes Phenomenon and Quantum Tunneling for de Sitter Radiation in Nonstationary Coordinates

We study quantum tunneling for the de Sitter radiation in the planar coordinates and global coordinates, which are nonstationary coordinates and describe the expanding geometry. Using the phase-integral approximation for the Hamilton-Jacobi action in the complex plane of time, we obtain the particle-production rate in both coordinates and derive the additional sinusoidal factor depending on the dimensionality of spacetime and the quantum number for spherical harmonics in the global coordinates. This approach resolves the factor of two problem in the tunneling method.Comment: LaTex 10 pages, no figur

Crotalus atrox venom preconditioning increases plasma fibrinogen and reduces perioperative hemorrhage in a rat model of surgical brain injury.

Perioperative bleeding is a potentially devastating complication in neurosurgical patients, and plasma fibrinogen concentration has been identified as a potential modifiable risk factor for perioperative bleeding. The aim of this study was to evaluate preconditioning with Crotalus atrox venom (Cv-PC) as potential preventive therapy for reducing perioperative hemorrhage in the rodent model of surgical brain injury (SBI). C. atrox venom contains snake venom metalloproteinases that cleave fibrinogen into fibrin split products without inducing clotting. Separately, fibrinogen split products induce fibrinogen production, thereby elevating plasma fibrinogen levels. Thus, the hypothesis was that preconditioning with C. atrox venom will produce fibrinogen spilt products, thereby upregulating fibrinogen levels, ultimately improving perioperative hemostasis during SBI. We observed that Cv-PC SBI animals had significantly reduced intraoperative hemorrhage and postoperative hematoma volumes compared to those of vehicle preconditioned SBI animals. Cv-PC animals were also found to have higher levels of plasma fibrinogen at the time of surgery, with unchanged prothrombin time. Cv-PC studies with fractions of C. atrox venom suggest that snake venom metalloproteinases are largely responsible for the improved hemostasis by Cv-PC. Our findings indicate that Cv-PC increases plasma fibrinogen levels and may provide a promising therapy for reducing perioperative hemorrhage in elective surgeries