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991.
Nephrotic syndrome type 1 is an inherited condition in which mutation of NPHS1 gene, which encodes nephrin protein, results increase permeability of glomerular capillary wall for macromolecules causes heavy proteinuria, hypoproteinemia, and edema. Nephrotic syndrome patients are resistant to steroid and immunosuppressive treatment. Natural products have traditionally been used to treat a number of chronic diseases. Present study was focused to investigate potency of different phytochemicals found in Boerhavia diffusa (B.diffusa) plant against mutant nephrin protein. The study involves virtual screening of total 66 bioactive compounds from B.diffusa plant against wild type and mutant models of Ig4 domain of nephrin protein through AutoDock raccoon. Based on binding energy and drug-likeness property, seven phytocompounds were screened. Hydrate-ligand docking (addition of explicit waters in ligands) method was used to select potential phytocompounds that could bind to mutant model of Ig4 domain of nephrin protein. For further prediction, molecular dynamics simulations with 100ns trajectory of Ig4 domain of nephrin protein in glycolipid bilayer membrane for systems such as wild, mutant, mutant model complex with boeravinone M and mutant model complex with boeravinone E were thoroughly studied. Hydrate-ligand docking result predicted boeravinone M and boeravinone E have shown better binding performance with mutant model. It causes due to hydration force field that measures entropy and enthalpy for each water molecule separately, allowing for more exact estimations of their contribution to ligand-protein interaction. Boeravinone E shows lowest short-range Lennard-Jones (LJ-SR) interaction energies of ?47.78 ± 12.7 kJ/mol. The results showed reduced compactness and stability nature of mutant model of Ig4 domain of nephrin protein, however, binding with boeravinone E has effectively modulated its stability and function by increasing its compactness. Current study may provide insight into therapeutic development of boeravinone E as a potential inhibitor against NPHS1in near future.  相似文献   
992.
Techniques for obtaining controlled fractures in sheet glass by means of thermal stress are outlined. The velocity behavior of fracture under different stress configurations is analyzed, and it is seen that the nature of crack is strongly influenced by the ambient stress field. The peak velocity of a typical free-running fracture is observed to be 1450 m/sec and the corresponding crack opening to be 4 microns.  相似文献   
993.
Permeability of Porous Media from Simulated NMR Response   总被引:2,自引:0,他引:2  
Nuclear Magnetic Resonance (NMR) is an increasingly popular well-logging tool in petroleum industry because it is the only tool that attempts to estimate formation permeability. In this paper, spatially correlated porous media are generated. Permeabilities of these media are computed by the lattice Boltzmann method. NMR relaxation responses are simulated by a random walk technique and formation factors are computed by solving a Laplacian equation. The testing of commonly used NMR permeability correlations shows that three conditions should be met for the validity of these correlations. The surface relaxivity should not vary significantly. The formation factor should depend only on porosity. And the characteristic pore body radius should be proportional to the characteristic throat radius. The correlations are improved by including surface relaxivity and formation factor.  相似文献   
994.
Averaged properties of bubbly liquids in the limit of large Reynolds and small Weber numbers are determined as functions of the volume fraction, mean relative velocity, and velocity variance of the bubbles using numerical simulations and a pair interaction theory. The results of simulations are combined with those obtained recently for sheared bubbly liquids [19] and the mixture momentum and continuity equations to propose a complete set of averaged equations and closure relations for the flows of bubbly liquids at large Reynolds and small Weber numbers.  相似文献   
995.
Castor oil based transparent polyurethane elastomers were synthesized, which can be used as an advanced catheter material. The effect of NCO: OH ratio on the structural, optical, thermal and physicomechanical properties of polyurethanes (PU) has been studied. The optical properties of the PU was analysed by studying its percentage transmittance and haze. The results showed a high transparency of 90.7% for the PU with a NCO: OH ratio of 0.9:1. Differential scanning calorimetry (DSC) analysis revealed an increase in the glass transition temperature (Tg) of PU with increasing hard segment content whereas thermogravimetric analysis (TGA) shows an increase in the initial decomposition temperature of PU from 262 to 268°C upon increasing the NCO: OH ratio from 0.9 to 1.5. A similar trend of increment in the tensile properties of PU has been observed as a consequence of increasing the molar ratio of NCO: OH. In vitro cytotoxicity analysis of PU was studied using human embryonic kidney (HEK293) cell line that revealed the nontoxic character of PU.  相似文献   
996.
Enriched metallic single‐walled carbon nanotubes (mSWCNTs) were dispersed in aqueous solution of partially oxidized graphene (po‐Gr). As‐prepared po‐Gr/mSWCNTs suspension was used to modify glassy carbon electrode (GCE) surface, which showed high electrocatalytic activity for dopamine (DA) oxidation in pH 7.0 phosphate buffered saline (PBS) solution. Using po‐Gr/mSWCNTs/GCE we could detect DA from 350 to 3600 nM, with a detection limit down to 25 nM in physiological condition (in pH 7.0 PBS); whereas, po‐Gr/GCE (without mSWCNTs) and bare GCE produced measurable signals only at or above 200 nM DA. Thus, the po‐Gr/mSWCNTs film we fabricated is a promising nanomaterial for fabrication of biosensors for nanomolar detection of DA.  相似文献   
997.
Sakram  B.  Sonyanaik  B.  Ashok  K.  Rambabu  S.  Ravi  D.  Kurumanna  A.  Shyam  P. 《Research on Chemical Intermediates》2017,43(3):1881-1892
Research on Chemical Intermediates - A simple and highly efficient green synthetic procedure has been described for the construction of...  相似文献   
998.
Let H be a product of countably infinite number of copies of an uncountable Polish space X. Let Σξ be the class of Borel sets of additive class ξ for the product of copies of the discrete topology on X (the Polish topology on X), and let . We prove in the Lévy-Solovay model that
for 1 ≤ ξ < ω 1.  相似文献   
999.
We experimentally demonstrate for the first time the focusing of optical beams within an inhomogeneous dielectric metamaterial with space-variant polarizability, implemented by etching subwavelength structures into a Silicon slab. Light focusing is obtained by creating an artificial slab material with graded refractive index profile. The local refractive index within the slab is modulated by controlling the duty cycle of the subwavelength structures. The demonstrated metamaterial based component can be integrated with various other building blocks towards the realization of devices and systems in free space optics on a chip configuration.  相似文献   
1000.
A new exchange-Coulomb semiempirical model potential energy surface for the He-N2 interaction has been developed. Together with two recent high-level ab initio potential energy surfaces, it has been tested for the reliability of its predictions of second-virial coefficients and bulk transport phenomena in binary mixtures of He and N2. The agreement with the relevant available measurements is generally within experimental uncertainty for the exchange-Coulomb surface and the ab initio surface of Patel et al. [J. Chem. Phys. 119, 909 (2003)], but with slightly poorer agreement for the earlier ab initio surface of Hu and Thakkar [J. Chem. Phys. 104, 2541 (1996)].  相似文献   
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