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Dynamic expression of α6 integrin indicates epidermal cell behaviors
No full textSkin epidermis is a stratified epithelium that composed of interfollicular epidermis (IFE) and hair follicles (HFs). Integrins are cell-cell and cell-matrix adhesive ligands that play important roles in epidermal cell proliferation, migration and differentiation behaviors. Here, we analyzed the expression of both α6 and β1 integrins. In vitro epidermal cell culture, both α6 and β1 integrins displayed downregulation upon high Ca2+ induced differentiation. During wound healing (WH), α6 integrin showed dynamic expression, first greatly upregulated in unclosed wounds and then downregulated upon re-epithelialization. Further analysis of different wound regions confirmed α6 integrin significantly increased in migratory cells and migration was coupled with differentiation. However, expression level of β1 integrin did not show significant correlation with migration. We discovered that α6 integrin directly indicates epidermal cell differentiation and wound directed migration behaviors with its expression level
Equivalence of an infinite one-dimensional ionic crystal to a simple electrostatic model
No full textIt is observed that the electrostatic potential created by the ions of an infinite one-dimensional ionic crystal at the position of a reference ion (for instance, a positive ion) is equivalent to the electrostatic potential created at the same point by a system of two identical uniformly charged straight wires each containing a charge equal to the opposite charge of the reference ion. The distance of the closest point of each wire relative to the reference ion and the length of the wires is equal to the distance separating any two adjacent ions in the regular lattice
Origin of the anomalous size-dependent increase of capacitance in boron nitride-graphene nanocapacitors
No full textThe anomalous size-dependent increase in capacitance in boron nitride-graphene nanocapacitors is a puzzle that has been initially attributed to the negative quantum capacitance exhibited by this particular materials system. However, we show in this work that the anomalous nanocapacitance of this system is not due to quantum effects but has pure electrostatic origin and can be explained by a parallel-plate (square) nanocapacitor model filled with a dielectric film characterized by a size/thickness-dependent relative permittivity. The model presented here is in excellent agreement with the experimentally measured capacitance values of recently fabricated graphene and hexagonal boron nitride nanocapacitors. The results obtained seem to suggest that the size-dependent increase of capacitance in the above-mentioned family of nanocapacitors can be explained by classical finite-size geometric electrostatic effects
Impacts of soil physicochemical properties and temporal-seasonal soil-environmental status on ground-penetrating radar response
No full textThe impacts of soils\u27 heterogeneity due to temporal (ET)- and seasonal (ES) changes from minute variations in precipitation (as rain, ice, and snow) and air temperatures (P+TA) on the ground-penetrating radar (GPR) responses (RGPR) are not rigorously tested. We aimed to understand how environmental changes (ET and ES) can be accountable to alter RGPR and help relate to real-time (TR) soil environmental status. Soil moisture (volumetric water content, VWC), temperature (TS), and electrical conductivity (EC) in every 30 min were recorded by soil sensors daily in different seasons to match the diurnal and seasonal changes. Readings of GPR alerts from six soil types of various GPR-suitability classes were recorded two to three times daily. Changes in P+TA, which changed physicochemical soil properties (PCSP) temporally and impacted RGPR up to 76%. The RGPR, which was negatively corelated with clay (R = -0.89) and organic matter (OM) (R = -0.91) percentages, remained low in soils when cation exchange capacity (CEC) is also high. The RGPR which were pronounced after rain, during fall, in sandy soils, and in case of neutral to basic pH impacted by narrow-range VWC variations on sandy but broad range on clay soils. Soils of same clay percent and similar OM acted differently if they have differential CEC and pH values. Ninety-six percent of RGPR, which is impacted by electric resistances and bonding nature of water and soils, were explainable if interactions of clay, OM, and VWC at TR are considered. Future insights on influences from freeze-thaw cycles and specific silica-mineral types of soils are required
Two Dimensional Mathematical Study of Flow Dynamics Through Emphysemic Lung
Get PDFThere are various lung diseases, such as chronic obstructive pulmonary disease, asthma, fibrosis, emphysema etc., occurred due to deposition of different shape and size particles. Among them we focused on flow dynamics of viscous air through an emphysemic lung. We considered lung as a porous medium and porosity is a function of tidal volume. Two dimensional generalized equation of momentum is used to study the flow of air and equation of motion is used to study the flow of nanoparticles of elongated shape. Darcy term for flow in porous media and shape factor for nonspherical nanoparticles are used in mathematical model. Finite difference technique is used to solve the governing equation numerically. Various parameters such as inlet Reynolds number, media porosity, Darcy number, breathing rate and particle shape factor are found on flow dynamics. Results demonstrated that during inhalation, breathing stress increases and the deposition of particles is smaller due to the rupture alveoli in an emphysematous lung as compared to healthy lung
Stability of a regular black holes thin-shell wormhole in Reissner-Nordstrom - De Sitter space-time
Get PDFThe dynamics regular black holes thin shell wormhole with a phantom energy equation of state in Reissner-Nordstrom - De sitter space-time is studied using the Darmois-Israel formalism. A mechanical stability analysis is carried out by using the standard perturbation method. The stable and unstable static solution depends on the suitable value of parameters
Kinetics and mechanism of the solid-acid catalyzed one-pot conversion of d-fructose to 5, 5′-[oxybis(methylene)]bis[2-furaldehyde] in dimethyl sulfoxide
No full textThe kinetics and the mechanism of Dowex 50WX8 catalyzed conversion of d-fructose to 5, 5′-[oxybis(methylene)]bis[2-furaldehyde] via the intermediate 5-hydroxymethylfurfural was studied in DMSO. The first order rate constants for two step process was determined at 383 and 393 K by monitoring the concentrations of 5-hydroxymethylfurfural and 5, 5′-[oxybis(methylene)]bis[2-furaldehyde]. The activation energies for d-fructose to 5-hydroxymethylfurfural conversion and dimerization to 5, 5′-[oxybis(methylene)]bis[2-furaldehyde] were determined as 48.2 and 24.5 kJ mol−1. A detailed mechanism with four acid catalyzed dehydration steps is proposed for the one-pot conversion of d-fructose to 5, 5′-[oxybis(methylene)]bis[2-furaldehyde] based on 1H NMR studies in DMSO-d6 at 393 K
Acidic ionic liquid catalyzed liquefaction of untreated switchgrass biomass in acetone and Pd-La(OTf)3 catalyzed reduction of the products
No full textThe cellulosic fraction of untreated switchgrass was partially liquefied by using acidic ionic liquid catalysts and heating in acetone at 120 °C for 3.5 h. The Brønsted acidic ionic liquids 1-(3-propylsulfonic)-3-methylimidazolium chloride and 1-(4-butylsulfonic)-3-methylimidazolium as catalysts produced 39.5% and 31.75% w/w liquefactions of switchgrass biomass and the lignin fraction remains unaffected by the mild conditions used. Sixteen C5-C15 range products were observed in the switchgrass liquefied product and 13 compounds were identified using GC-MS, including three products arising from dimerization of acetone under acidic conditions used. The liquefied product could be partially reduced by catalytic hydrogenation using Pd-La(OTf)3 catalyst system in 50% aq. acetic acid at 200 °C, 1.38 MPa for 16 h. Thirteen, mainly alcohol and ketone products were identified in the catalytically reduced liquefied product
Radiation Effects on Boundary Layer Flow of Cu-water and Ag-water Nanofluids over a Stretching Plate with Suction and Heat Transfer with Convective Surface Boundary Condition
Get PDFThis paper deals with boundary layer flow of Cu-water and Ag-water nanofluids past a stretching plate with suction and heat transfer with convective surface boundary condition in the presence of thermal radiation. This flow belongs to the boundary layer flow of Skiadis type. A closed form solution has been obtained for convective heat transfer under the given conditions. We study the flow field with suction on stretching surface, the effect of volume fraction of nano-sized particles of Cu in Cu-water and Ag in Ag-water nanofluids on the temperature field, and the effect of suction parameter on the convective heat transfer. Moreover, the skin friction and Nusselt number both have been calculated and the possible effect of related parameters has been studied