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71.
Dr. Vijay Kumar Dr. Guru Krishna Kumar Viswanathan Dr. Krittika Ralhan Prof. Ehud Gazit Prof. Daniel Segal 《ChemMedChem》2021,16(23):3565-3568
The von Hippel-Lindau tumor suppressor protein (pVHL) is involved in maintaining cellular oxygen homeostasis through the regulated degradation of HIF-α. The intrinsically disordered nature of pVHL makes it prone to aggregation that impairs its function, and this is further aggravated in mutant versions of the protein, thus promoting tumor development. By using in silico analysis, we predicted six peptide fragments from pVHL to be amyloidogenic. This was verified for two of the peptides by biophysical approaches, which demonstrated self-assembly and formation of β-sheet-rich aggregates, which, under transmission electron microscopy, atomic force microscopy, and X-ray diffraction, displayed typical fibrillar amyloid characteristics. These motifs may serve as proxies for exploring the nature of pVHL aggregation. 相似文献
72.
Silicon - Nowadays, the starring attentions of the polylactic acid based composites are improved due to environmental awareness and diminution of petroleum oil. The bio-plastics were restricted to... 相似文献
73.
Alam Ashraful Hariyanto Bambang Ullah Hayat Salin Krishna R. Datta Avishek 《SILICON》2021,13(9):3153-3162
Silicon - Silicon (Si) plays an important role in mitigating adverse effects of various biotic and abiotic stresses including drought. Polyhouse experiment was conducted to evaluate the effects of... 相似文献
74.
M.Veera Krishna 《中国化学工程学报》2021,34(6):40-52
The investigation of radiation-absorption,chemical reaction,Hall and ion-slip impacts on unsteady MHD free convective laminar flow of an incompressible viscous,electrically conducting and heat generation/absorbing fluid enclosed with a semi-infinite porous plate within a rotating frame has been premeditated.The plate is assumed to be moving with a constant velocity in the direction of fluid movement.A uniform transverse magnetic field is applied at right angles to the porous surface,which is absorbing the fluid with a suction velocity changing with time.The non-dimensional governing equations for present inves-tigation are solved analytically making use of two term harmonic and non-harmonic functions.The graphical results of velocity,temperature and concentration distributions on the analytical solutions are displayed and discussed with reference to pertinent parameters.It is found that the velocity profiles decreased with an increasing in Hartmann number,rotation parameter,the Schmidt number,heat source parameter,while it increased due to an increase in permeability parameter,radiation-absorption param-eter,Hall and ion slip parameters.However,the temperature profile is an increasing function of radiation-absorption parameter,whereas an increase in chemical reaction parameter,the Schmidt num-ber Sc or frequency of oscillations decrease the temperature profile on cooling.Also,it is found that the concentration profile is decreased with an escalating in the Schmidt number or the chemical reaction parameter. 相似文献
75.
Chandrasekharam N. Nagineni Sarwat Naz Rajani Choudhuri Gadisetti V. R. Chandramouli Murali C. Krishna Jeffrey R. Brender John A. Cook James B. Mitchell 《International journal of molecular sciences》2021,22(9)
Understanding the global metabolic changes during the senescence of tumor cells can have implications for developing effective anti-cancer treatment strategies. Ionizing radiation (IR) was used to induce senescence in a human colon cancer cell line HCT-116 to examine secretome and metabolome profiles. Control proliferating and senescent cancer cells (SCC) exhibited distinct morphological differences and expression of senescent markers. Enhanced secretion of pro-inflammatory chemokines and IL-1, anti-inflammatory IL-27, and TGF-β1 was observed in SCC. Significantly reduced levels of VEGF-A indicated anti-angiogenic activities of SCC. Elevated levels of tissue inhibitors of matrix metalloproteinases from SCC support the maintenance of the extracellular matrix. Adenylate and guanylate energy charge levels and redox components NAD and NADP and glutathione were maintained at near optimal levels indicating the viability of SCC. Significant accumulation of pyruvate, lactate, and suppression of the TCA cycle in SCC indicated aerobic glycolysis as the predominant energy source for SCC. Levels of several key amino acids decreased significantly, suggesting augmented utilization for protein synthesis and for use as intermediates for energy metabolism in SCC. These observations may provide a better understanding of cellular senescence basic mechanisms in tumor tissues and provide opportunities to improve cancer treatment. 相似文献
76.
Quasi-isotropic. laminates have isotropic elastic properties in all in-plane directions. Therefore, this kind of laminate is widely used for structural elements. The simplest stacking sequence of quasi-isotropic laminates is [0/-60/60]s. When the direction of applied axial load to [0/-60/60]s laminate is inclined at a 30-degree angle, we have the other quasi-isotropic laminate [30/-30/90]s under axial load. The failure mechanisms of these two laminates are, however, entirely different from each other because these two laminates have different distribution of the interlaminar stresses. It was confirmed by tensile fatigue tests that the [0/-60/60]s laminate does not show any visible fatigue damage, but the [30/-30/90]s laminate develops edge-delamination during cyclic loading. The analytical results were in good agreement with the experimental results. 相似文献
77.
Krishna K. Seijger G. B. F. van den Bleek C. M. Makkee M. Calis H. P. A. 《Topics in Catalysis》2004,30(1-4):115-121
Topics in Catalysis - Several zeolite-based catalysts containing Ce3+ and/or CeO2 were prepared by a variety of catalyst preparation techniques like ion exchange, solid-state ion exchange,... 相似文献
78.
A. G. Gopala Krishna J. V. Prabhakar 《Journal of the American Oil Chemists' Society》1994,71(6):645-647
Antioxidant efficacy of the amino acids methionine, tryptophan, aspartic acid, serine, alanine and arginine in methyl linoleate
were compared to a methyl linoleate control at 2,50 or 79% relative humidity (RH) at 37°C. Antioxidant efficacy varied with
RH and the individual amino acids. Arginine had the highest antioxidant efficacy at all RH values compared to the control.
The efficacy of alanine was equal to that of arginine at RHs of 50 and 79% but was lower at 2% RH. The presence of aliphatic,
alkaline amino, hydroxyl or thiol groups in the side chain of the amino acids increased the antioxidant efficacy at high RHs. 相似文献
79.
Mussoorrie rock phosphate (MRP), MRP + pyrite (25% by weight), diammonium phosphate (DAP), ammonium polyphosphate (APP) and nitrophosphate (NP) were compared in a field experiment as fertilizers for wheat. At 20 kg P ha–1, MRP was only 6 per cent as effective as DAP. However, when it was mixed with pyrite, the efficiency of MRP increased to 64 per cent at 20 kg P ha–1 compared with 97 per cent at 40 kg P ha–1. The P requirement for a targeted yield for 4.5 t ha–1 decreased from 39.4 kg P ha–1 as MRP to 23.7 kg P ha–1 as MRP + pyrite. Of the other P fertilizers studied, NP was as effective as DAP, whereas APP was 9 to 37 per cent more effective than DAP. However, the P requirement as DAP, NP and APP for a targeted yield of 4.5 t ha–1 was similar (11 ± 0.5 kg P ha–1). 相似文献
80.
M. Arun Prasad 《Electrochimica acta》2004,49(3):445-453
The parametric dependence of the diffusion layer thickness upon electrode potential and scan rate has been derived for reversible electron transfer processes in linear sweep voltammetry (LSV) using a simple analytical expression for the dimensionless current function. The quantitative variation of the conductance with potential and scan rate has been illustrated and the equivalent circuit pertaining to LSV has been proposed. Several earlier results pertaining to potential step experiments, thin layer voltammetry, surface bound LSV, radial flow at micro-ring electrodes, etc. are shown to arise from the general expression for the current function obtained here, thus indicating an isomorphism among various potential perturbation techniques. 相似文献