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161.
K. Rahimunnisa J. Kirubavathy J. Jayakumar S. Suresh Kumar 《International Journal of Electronics》2013,100(2):182-193
A new architecture for encrypting and decrypting the confidential data using Advanced Encryption Standard algorithm is presented in this article. This structure combines the folded structure with parallel architecture to increase the throughput. The whole architecture achieved high throughput with less power. The proposed architecture is implemented in 0.13-µm Complementary metal–oxide–semiconductor (CMOS) technology. The proposed structure is compared with different existing structures, and from the result it is proved that the proposed structure gives higher throughput and less power compared to existing works. 相似文献
162.
Ravikirana R. Mythili S. Raju T. Jayakumar E. Rajendra Kumar 《Materials Science & Technology》2015,31(4):448-459
The present paper presents the results of an extensive electron microscopy investigation on the decomposition modes of high temperature austenite in 9Cr–W–V–Ta reduced activation ferritic–martensitic steels. Although the displacive martensitic transformation is predominant on austenitisation, low volume fraction of Fe rich M3C or M23C6 precipitates formed, when the tungsten content exceeded 1 wt-%. The compositional inhomogeneity introduced in the austenite by the nature, chemistry and kinetics of dissolution of the pre-existing carbides is dependent on the steel composition and austenitisation conditions. The extent of repartitioning of tungsten between M23C6 and ferrite largely influences the kinetics of austenite and martensite transformation, for the same austenitisation conditions. Supporting evidence from calorimetry analysis is also presented. 相似文献
163.
164.
A Callaway W Liu V Andrianov L Stenzler J Zhao S Wettlaufer P Jayakumar SH Howell 《Canadian Metallurgical Quarterly》1996,9(9):810-818
Two Arabidopsis ecotypes are resistant to systemic infection by cauliflower mosaic virus (CaMV), a plant para-retrovirus. Arabidopsis ecotype Enkheim-2 (En-2) is highly resistant to CaMV infection while Bla-14 is more weakly resistant. CaMV resistance in En-2 can be largely attributed to the action of a single semidominant gene called cauliflower mosaic virus resistance1 (CAR1), located at a locus on chromosome 1. Resistance in Bla-14 is tightly linked to CAR1 and may be due to a weak allele at the same locus or another gene in a gene cluster. A quantitative polymerase chain reaction assay in conjunction with replication- and movement-incompetent viral mutants was used to determine whether virus replication or movement is affected in the resistant ecotypes. The pattern of accumulation of the wild-type virus in the resistant ecotype, En-2, was similar to that of a movement-incompetent CaMV mutant, suggesting that CAR1 interferes with or fails to support CaMV movement. CaMV-inoculated En-2 plants do not show visible signs of a hypersensitive response. However, indicators of an induced defense response do appear in CaMV-infected En-2 plants, such as the activation of pathogenesis-related protein gene expression and the production of camalexin, an Arabidopsis phytoalexin. Defense responses induced chemically or by mutation in the susceptible ecotypes delayed and reduced the severity of a CaMV infection. These findings suggest that CAR1 acts either in the susceptible ecotype to support virus movement or in the resistant ecotype to signal a defense response. 相似文献
165.
Jun Hon Pang Yasmin Farhatnia Fatemeh Godarzi Aaron Tan Jayakumar Rajadas Brian G. Cousins Alexander M. Seifalian 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(47):6248-6264
Improving patency rates of current cardiovascular implants remains a major challenge. It is widely accepted that regeneration of a healthy endothelium layer on biomaterials could yield the perfect blood‐contacting surface. Earlier efforts in pre‐seeding endothelial cells in vitro demonstrated success in enhancing patency, but translation to the clinic is largely hampered due to its impracticality. In situ endothelialization, which aims to create biomaterial surfaces capable of self‐endothelializing upon implantation, appears to be an extremely promising solution, particularly with the utilization of endothelial progenitor cells (EPCs). Nevertheless, controlling cell behavior in situ using immobilized biomolecules or physical patterning can be complex, thus warranting careful consideration. This review aims to provide valuable insight into the rationale and recent developments in biomaterial strategies to enhance in situ endothelialization. In particular, a discussion on the important bio‐/nanoengineering considerations and lessons learnt from clinical trials are presented to aid the future translation of this exciting paradigm. 相似文献
166.
Elumalai Gnanamani Nagamalla Someshwar Jayakumar Sanjeevi Chinnasamy Ramaraj Ramanathan 《Advanced Synthesis \u0026amp; Catalysis》2014,356(10):2219-2223
The conformationally rigid chiral bicyclic skeleton tethered bipyridine N,N′‐dioxide (−)‐ 9 has been designed, synthesized and examined as an organocatalyst in the enantioselective ring opening of meso‐epoxides using tetrachlorosilane (SiCl4). The catalyst (−)‐ 9 is found to exhibit good enantioselectivity for substituted cis‐stilbene epoxides; whereas, the saturated cyclic meso‐epoxides display a moderate enantioselectivity. At −30 °C in chloroform, the catalyst (−)‐ 9 with 0.5 mol % loading generated the chlorohydrins in up to 97 % yield with up to 93 % ee. The possible creation of transient axial chiral environment around hypervalent silicon species due to the presence of conformationally rigid chiral bicyclic skeleton tethered bipyridine N,N′‐dioxide may be responsible for such enantioselectivity observed in the desymmetrization of meso‐epoxides.
167.
Sangeetha Jayakumar Vadivel Mani Thangavelu Saravanan Karunanithi Rajamanickam Alex Daniel Prabhu John Philip 《应用聚合物科学杂志》2021,138(42):51252
We report here the development of multifiller nanocomposite containing gadolinium oxide and bismuth nanofillers with enhanced X-ray attenuation property. The mass attenuation coefficient of the nanocomposite is found to be 5.26 (X-ray attenuation: 95%) and 2.22 cm2/g (X-ray attenuation: 71%), respectively, under dental and lung X-ray scan conditions. Fourier transform infrared spectroscopy confirms the interfacial interaction between Gd2O3 nanofillers and the polymer matrix through hydrogen bonding. Atomic force microscopy images of the nanocomposite show a smooth and uniform topography with an average surface roughness of ~19 nm. Thermogravimetric analysis confirms the thermal stability of the nanocomposite upto 384°C. The enhanced X-ray attenuation property of the nanocomposite is attributed to the good interfacial bonding, dual k-edge effect of nanofillers and their uniform distribution within the polymeric matrix. Therefore, this nanocomposite is a promising material for diagnostic X-ray shielding, especially as, thyroid collar, gonad shield, aprons, gloves, and so on. 相似文献
168.
Ramaswamy Srividhya Lakshmi Chinnappan Jayakumar 《Journal of Intelligent Information Systems》2022,58(2):379-404
Journal of Intelligent Information Systems - Sentiment analysis for user reviews has received substantial heed in recent years. There are many deep learning models for natural language processing... 相似文献
169.
Prasantha Bharathi Dhandapani Dumitru Baleanu Jayakumar Thippan Vinoth Sivakumar 《计算机系统科学与工程》2021,37(3):331-346
In this research, we propose a new change in classical epidemic models by including the change in the rate of death in the overall population. The existing models like Susceptible-Infected-Recovered (SIR) and Susceptible-Infected-Recovered-Susceptible (SIRS) include the death rate as one of the parameters to estimate the change in susceptible, infected and recovered populations. Actually, because of the deficiencies in immunity, even the ordinary flu could cause death. If people’s disease resistance is strong, then serious diseases may not result in mortalities. The classical model always assumes a closed system where there is no new birth or death, no immigration or emigration, while in reality, such assumptions are not realistic. Moreover, the classical epidemic model does not report the change in population due to death caused by a disease. With this study, we try to incorporate the rate of change in the population of death caused by a disease, where the model is framed to reduce the curve of death along with the susceptible and infected populations. Since the rate of change turned out to be very small, we have tried to estimate it fractionally. Thus, the model is defined using fuzzy logic and is solved by two different methods: a Laplace Adomian decomposition method (LADM) and a differential transform method (DTM) for an arbitrary order α. To test its accuracy, we compared the results of both DTM and LADM with the fourth-order Runge-Kutta method (RKM-4) at α = 1. 相似文献
170.
Monolithic 3D porous silica structures are fabricated into a multilayer framework with a bimodal pore size distribution in the micrometer and sub‐micrometer range. The fabrication – which involves directed assembly of colloidal spheres, transfer printing, and removal of a sacrificial template – yields robust and mechanically stable structures over a large area. The structure becomes monolithic upon pyrolyzing the stacked layers, which induces necking of the particles. The monolithic microstructures can easily be embedded in microchannels with the aid of photolithography, leading to the formation of a microfluidic system with a built‐in microstructure in a site‐ and shape‐controlled manner. Utilization of the system results in a fourfold increase in the mixing efficiency in the microchannel. 相似文献