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951.
Ripon Sarkar Aritri Ghosh Ananya Barui Pallab Datta 《Journal of materials science. Materials in medicine》2018,29(3):31
Topical application of honey for tissue regeneration, has recently regained attention in clinical practice with controlled studies affirming its efficacy and indicating its role in regeneration over repair. Parallely, to overcome difficulties of applying raw honey, several product development studies like nanofibrous matrices have been reported. However, one approach concentrated on achieving highest possible honey loading in the nanofiber membranes while other studies have found that only specific honey dilutions result in differential cellular responses on wound healing and re-epithelization. From these results, it can be suggested that high honey loading provides optimum external microenvironment, low-loaded membranes could provide a more conducive internal microenvironment for tissue regeneration. With this hypothesis, this paper sought to evaluate ability of low-honey loaded nanofibers to modulate the anti-oxidant, anti-biofilm and anti-inflammatory properties which are important to be maintained in wound micro-environment. A loading-dependent reduction of biofilm formation and anti-oxidant activity was noted in different concentration ranges investigated. After scratch assay, a certain honey loading (0.5%) afforded the maximum re-epithelization. Since there is lack of methods to determine anti-inflammatory properties of nanofiber membranes during epithelial healing process, we performed anti-inflammatory assessment of nano-fibers by evaluating the expressions of pro-inflammatory markers-Cycloxygenase-2 (COX-2) and Interleukin-6 (IL-6) and to confirm the optimized concentration. Considering the role of COX-2 and IL-6, the novel methodology used in this study can also be developed as an assay for anti-inflammatory matrices for wound healing. 相似文献
952.
Matias I.R. Lopez-Amo M. Fiksman G. Datta P. Oton J.M. 《IEEE journal of selected topics in quantum electronics》1997,3(3):780-788
The dynamic response, modeling and performance of a new optical intensity induced shutter have been studied. Hybrid optical waveguides made of optical fibers and photochromic doped gel-glass have been prepared by sol-gel process. A novel theoretical model explaining their behavior is shown, Experimental validation of the model is also shown. Design parameters of the devices, optical tunability and their application as extrinsic fiber optic intensity induced shutter (EFIS) are theoretically and experimentally demonstrated 相似文献
953.
A. K. L. Srivastava P. K. Datta A. H. Sheikh 《International Journal of Mechanical Sciences》2003,45(1):1299-93
The buckling and vibration characteristics of stiffened plates subjected to in-plane partial and concentrated edge loadings are studied using finite element method. The initial stresses are obtained considering the pre-buckling conditions. Buckling loads and vibration frequencies are determined for different plate aspect ratios, edge conditions and different partial non-uniform edge loading cases. The non-uniform loading may also be caused due to the supports on the edges. The analysis presented determines the stresses all over the region for different kinds of loading and edge conditions. In the structural modelling, the plate and the stiffeners are treated as separate elements where the compatibility between these two types of elements is maintained. The vibration characteristics are discussed and the results are compared with those available in the literature. Buckling results show that the stiffened plate is less susceptible to buckling for position of loading near the supported edges and near the position of stiffeners as well. 相似文献
954.
Hai‐Tian Zhang Lu Guo Greg Stone Lei Zhang Yuan‐Xia Zheng Eugene Freeman Derek W. Keefer Subhasis Chaudhuri Hanjong Paik Jarrett A. Moyer Michael Barth Darrell G. Schlom John V. Badding Suman Datta Venkatraman Gopalan Roman Engel‐Herbert 《Advanced functional materials》2016,26(36):6612-6618
Materials exhibiting electronic phase transitions have attracted widespread attention. By switching between metallic and insulating states under external stimuli, the accompanying changes in the electrical and optical properties can be harnessed in novel electronic and optical applications. In this work, a laterally confined conductive pattern is inscribed into an otherwise insulating VO2 thin film using ultraviolet light, inducing an almost four orders of magnitude decrease in electrical resistivity of the exposed area. The metallic imprint remains in VO2 after ultraviolet light exposure and can be completely erased by a short low temperature anneal. The ability to optically pattern confined metallic structures provides new opportunities for reconfigurable photonic and plasmonic structures, as well as re‐writable electric circuitry. 相似文献
955.
The dielectric constant (K) and dielectric loss (tan ) of preheated chrysotile asbestos up to 900°C were measured in the frequency range 102 to 105 Hz. TheK and tan values were also measured as a function of temperature for hot pressed powdered pellets of chrysotile asbestos. The d.c. conductivity of hot pressed powdered pellets of chrysotile asbestos was also measured as a function of temperature. Dynamic d.c. conductivity was measured in the temperature range 58 to 580° C. The results have been discussed and attempts made to establish a correlation between the structural changes with the variation of dielectric properties. 相似文献
956.
SCS-CN Based Quantification of Potential of Rooftop Catchments and Computation of ASRC for Rainwater Harvesting 总被引:3,自引:1,他引:2
P. K. Singh B. K. Yaduvanshi Swati Patel Saswati Ray 《Water Resources Management》2013,27(7):2001-2012
Rooftop rainwater harvesting, among other options, play a central role in addressing water security and reducing impacts on the environment. The storm or annual storm runoff coefficient (RC/ASRC) play a significant role in quantification of potential of rooftop catchments for rainwater harvesting, however, these are usually selected from generic lists available in literature. This study explores methodology/procedures based on one of the most popular and versatile hydrological model, Soil Conservation Service Curve Number (SCS-CN) (SCS 1986) and its variants, i.e., Hawkins SCS-CN (HSCS-CN) model (Hawkins et al. 2001), Michel SCS-CN (MSCS-CN) model (Michel et al. Water Resour Res 41:W02011, 2005), and Storm Water Management Model-Annual Storm Runoff Coefficient (SWMM-ASRC) (Heaney et al. 1976) and compares their performance with Central Ground Board (CGWB) (CGWB 2000) approach. It has been found that for the same amount of rainfall and same rooftop catchment area, the MSCS-CN model yields highest rooftop runoff followed by SWMM-ASRC?>?HSCS-CN?>?SCS-CN?>?CGWB. However, the SCS-CN model has close resemblance with CGWB approach followed by HSCS-CN model, SWMM-ASRC, and MSCS-CN model. ASRCs were developed using these models and it was found that MSCS-CN model has the highest value of ASRC (= 0.944) followed by SWMM-ASRC approach (=0.900), HSCS-CN model (=0.830), SCS-CN model (=0.801), and CGWB approach (=0.800). The versatility of these models lies to the fact that CN values (according to rooftop catchment characteristics) would yield rooftop runoff and therefore ASRC values based on sound hydrological perception and not just on the empiricism. The models have inherent capability to incorporate the major factors responsible for runoff production from rooftop/urban, i.e., surface characteristics, initial abstraction, and antecedent dry weather period (ADWP) for the catchments and would be better a tool for quantification rather than just using empirical runoff coefficients for the purpose. 相似文献
957.
EVs hold great promise as a means of reducing greenhouse gas emissions, providing consumers with low-cost renewable fuel and ensuring a cleaner, more sustainable transportation system. To achieve this promise, it is essential to minimize the total cost of ownership (TCO) for the user. EV tariffs are one of policymakers’ most potent weapons in reducing TCO. This article describes the role of such tariffs and addresses key challenges in their implementation. 相似文献
958.
The paper proposes a band-pass correlation filter in frequency domain for frontal face recognition task under both poor illumination and noisy condition. The band-pass nature of the proposed filter is achieved through combination of a modified high-pass filter and a continuous wavelet filter. An optimal range of scale is selected for this wavelet filter. The performance of the proposed band-pass correlation filter for face recognition tasks under variations in illumination and noise is evaluated and compared with other filters using standard databases (YaleB and PIE). High recognition accuracy is achieved in this proposed technique. 相似文献
959.
Ammoniacal leaching and sulfuric acid leaching were explored separately to recover copper from smelter slag. The overall 75% copper recovery was achieved from the smelter slag under optimum condition using ammoniacal leaching. The low copper recovery in this process is directly related to the complex slag mineralogy and dissolution kinetics. To overcome such problems, sulfuric acid leaching was applied separately. This method provided an overall 89% copper recovery under atmospheric condition. The use of sulfuric acid as the leaching agent was found to be more advantageous than ammonia due to the complex interlocking nature of copper bearing particles and different reaction kinetics of the slag. 相似文献
960.
Jie FanSomnath Datta 《Computational statistics & data analysis》2011,55(12):3295-3303
Methods for analyzing clustered survival data are gaining popularity in biomedical research. Naive attempts to fitting marginal models to such data may lead to biased estimators and misleading inference when the size of a cluster is statistically correlated with some cluster specific latent factors or one or more cluster level covariates. A simple adjustment to correct for potentially informative cluster size is achieved through inverse cluster size reweighting. We give a methodology that incorporates this technique in fitting an accelerated failure time marginal model to clustered survival data. Furthermore, right censoring is handled by inverse probability of censoring reweighting through the use of a flexible model for the censoring hazard. The resulting methodology is examined through a thorough simulation study. Also an illustrative example using a real dataset is provided that examines the effects of age at enrollment and smoking on tooth survival. 相似文献