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21.
Stimulation of T-cells by IL-2 has been exploited for treatmentof metastatic renal carcinoma and melanoma. However, a narrowtherapeutic window delimited by negligible stimulation of T-cellsat low picomolar concentrations and undesirable stimulationof NK cells at nanomolar concentrations hampers IL-2-based therapies.We hypothesized that increasing the affinity of IL-2 for IL-2R  相似文献   
22.
Organic coatings applied on cathodically protected metallic structures must have good resistance to cathodic delamination or disbonding (CD). Both environmental conditions and coating composition influence the CD resistance. In the present study, the effect of types of epoxy resin, curing agents and their mixing ratio on cathodic delamination rate was studied in a high-build pigmented coating. Furthermore, the influence of platey fillers on CD resistance was also studied. In order to bring out correlations, if any, between adhesion and CD resistance, pull-off adhesion strengths (both dry and wet) of these coatings were also measured. Fairly good correlation was found between residual (wet) pull-off adhesion strength and CD resistance. When tested at 60 and 90°C, all the coatings under investigation showed chalking. Among the coatings under investigation, the one based on Bisphenol F epoxy and modified cycloaliphatic amine adduct exhibited excellent CD resistance.  相似文献   
23.
Balaji  B.  Rao  K. Srinivasa  Sravani  K. Girija  Aditya  Marupaka 《SILICON》2022,14(13):7857-7861
Silicon - A unique structure of GaAs/6H-SiC/InGaN metal–semiconductor field-effect transistor has been proposed and demonstrated in this work. The proposed GaAs/6H-SiC/InGaNMetal...  相似文献   
24.
Sravani  Sadhu Satya  Balaji  B.  Rao  K. Srinivasa  Babu  A. Narendra  Aditya  M.  Sravani  K. Girja 《SILICON》2022,14(15):9263-9273
Silicon - Tunnel Field Effect Transistor (TFET) has become one of the promising devices to be part of Integrated circuits as the technology advances to the nanoscale. A TFET has many advantages...  相似文献   
25.
Nitric acid leachout characteristics from weak base anion exchanger (WBA) have been experimentally evaluated as a function of total nitric acid loading at a given flow velocity. An empirical first order model is used to explain the column outlet behaviour. Based on the experimental evaluation, a column configuration of a strong acid cation exchanger (SAC) topped mixed bed of SAC and WBA followed by a 5% nitric acid loaded WBA as the bottom layer of the column has been used to remove Gd(NO3)3 from water while maintaining the column outlet pH in the range of 5.0–5.5.  相似文献   
26.
Transforming growth factor-beta (TGF-β), a member of the TGF-β cytokine superfamily, is known to bind to sulfated glycosaminoglycans (GAGs), but the nature of this interaction remains unclear. In a recent study, we found that preterm human milk TGF-β2 is sequestered by chondroitin sulfate (CS) in its proteoglycan form. To understand the molecular basis of the TGF-β2–CS interaction, we utilized the computational combinatorial virtual library screening (CVLS) approach in tandem with molecular dynamics (MD) simulations. All possible CS oligosaccharides were generated in a combinatorial manner to give 24 di- (CS02), 192 tetra- (CS04), and 1536 hexa- (CS06) saccharides. This library of 1752 CS oligosaccharides was first screened against TGF-β2 using the dual filter CVLS algorithm in which the GOLDScore and root-mean-square-difference (RMSD) between the best bound poses were used as surrogate markers for in silico affinity and in silico specificity. CVLS predicted that both the chain length and level of sulfation are critical for the high affinity and high specificity recognition of TGF-β2. Interestingly, CVLS led to identification of two distinct sites of GAG binding on TGF-β2. CVLS also deduced the preferred composition of the high specificity hexasaccharides, which were further assessed in all-atom explicit solvent MD simulations. The MD results confirmed that both sites of binding form stable GAG–protein complexes. More specifically, the highly selective CS chains were found to engage the TGF-β2 monomer with high affinity. Overall, this work present key principles of recognition with regard to the TGF-β2–CS system. In the process, it led to the generation of the in silico library of all possible CS oligosaccharides, which can be used for advanced studies on other protein–CS systems. Finally, the study led to the identification of unique CS sequences that are predicted to selectively recognize TGF-β2 and may out-compete common natural CS biopolymers.  相似文献   
27.
This study reports the results of a numerical investigation of turbulent natural convection in a square enclosure with localized heating from below and symmetrical cooling from the vertical side walls. The present study simulates the case of an accidental heat generation due to fire in a typical isolated building of a nuclear reactor or electronic components cabin. The source of fire is considered to be centrally located at the bottom wall with different heated widths, which is assumed to be either isothermal or with isoflux. For the purpose of the analysis, the source length is varied from 20 to 80% of the total width of the bottom wall. The top wall and the unheated portion of the bottom wall are considered to be adiabatic, whereas sidewalls are isothermal. Steady as well as transient forms of two-dimensional Reynolds–Averaged-Navier–Stokes equations and conservation equations of mass and energy, coupled with the Boussinesq approximation, are solved by the control volume based discretisation method employing the SIMPLE algorithm for pressure–velocity coupling. Turbulence is modeled using the standard kε model. Rayleigh number, Ra, based on the enclosure height is varied from 108 to 1012. Stream lines and isotherms are presented for various combinations of Ra and the heated width. A double cell flow pattern is observed with marginal loss in symmetry as Ra increases. The results are reported in the form of local and average Nusselt number on the heated floor. Correlations are developed to predict the heat transfer rates from the enclosure as a function of dimensionless heated width of the bottom wall and Ra, by least square linear regression analysis.  相似文献   
28.
A completely energy-independent microgrid (green microgrid) was examined in this work with the aims of abating greenhouse gas emissions by spreading the use of green energy, providing energy backup systems for disaster, and increasing the energy utilization efficiency with the use of exhaust heat. This paper analyzed the energy supply to six houses in a cold region. The green microgrid consisted of photovoltaics, water electrolyzers, proton-exchange membrane fuel cells (PEFCs), and heat pumps. To investigate the operation method and the capacity of each piece of equipment in the arrangement, a distributed system with two or more sets of equipment and a central system with one set of equipment were analyzed by a genetic algorithm. By introducing the prior energy need pattern of a cold region into the proposed system, the operation method and equipment capacity based on the power and heat balance were clarified. By introducing the partial load performance of a water electrolyzer and a PEFC into the analysis program, the operation method of each system was investigated. It was found that the area of a solar cell of a distributed system could be reduced by 12% as compared to a central system.  相似文献   
29.
This paper reports the results of an analytical and numerical investigation to determine the effect of internal heat generation on the onset of convection, in a differentially heated shallow fluid layer. The case with the bottom plate at a temperature higher than the top plate mimics the classical Rayleigh Benard convection. However, internal heat generation adds a new dimension to the problem. Linear stability analysis is first carried out for the case of an infinitely wide cavity. The effect of aspect ratio on the onset of convection is studied by solving the full Navier–Stokes equations and the equation of energy and observing the temperature contours. A bisection algorithm is used for an accurate prediction of the onset. The numerical results are used to plot the stability curves for eight different aspect ratios. A general correlation is developed to determine the onset of convection in a differentially heated cavity for various aspect ratios. For an aspect ratio of 10, it is seen that the cavity approaches the limit of an infinite cavity. Analytical results obtained by using linear stability analysis agree very well with the “full” CFD simulations, for the above aspect ratio.  相似文献   
30.
Delineation of groundwater potential zones (GWPZ) has been performed for a coastal groundwater basin of eastern India. The groundwater potential zone index (GWPZI) map is generated by using Analytic Hierarchy Process (AHP) from different influencing features, e.g., Land Use/Land Cover (LU/LC), soil (S), geomorphology (GM), hydrogeology (HG), surface geology (SG), recharge rate (RR), drainage density (DD), rainfall (RF), slope (Sl), surface water bodies (SW), lineament density (LD), and Normalized Difference Vegetative Index (NDVI). Recharge rate values are estimated from hydrological water balance model. Overlay weighted sum method is used to integrate all thematic feature maps to generate GWPZ map of the study area. Four zones have been identified for the coastal groundwater basin [very good: 36.39 % (273.53 km2, good: 43.57 % (327.47 km2), moderate: 18.27 % (137.30 km2), and poor: 1.77 % (13.27 km2)]. Areas in north to south-west and south-east direction show very good GWPZ due to the presence of low drainage density. GWPZ map and well yield values show good agreement. Sensitivity analysis reveals that exclusion/absence of rainfall and lineament density increases the poor groundwater potential zones. Omission of hydrogeology, soils, surface geology, and NDVI show maximum increase in good GWPZ. Obtained GWPZ map can be utilized effectively for planning of sustainable agriculture. This analysis demonstrates the potential applicability of the methodology for a general coastal groundwater basin.  相似文献   
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