174 research outputs found
Security against Timing Analysis Attack
Timing attack is the type of side-channel attack involves the time taken to complete critical operations. Securing crypto processor from timing attack is critical issue. This paper implements the Bernstein’s Timing Attack and timing attack based on hamming weight. The countermeasures of Bernstein’s Timing attack are implemented in our experimental test bed and their performance is compared. This paper also proposes the key recovery method based on timing attack using hamming weight of the key
Magnetic properties of Al, V, Mn, and Ru impurities in Fe–Co alloys
Theoretical studies on the magnetic properties of impurities in Fe–Co alloys have been carried out using a molecular-orbital approach within a gradient corrected density functional formalism. The defected alloy is modeled by a large cluster and the calculations on the ordered alloy are used to show that a cluster containing 67 atoms can provide quantitative information on the local magnetic moment. It is found that although bulk Al, V, and Ru are nonmagnetic, all the impurities carry finite moments. While Al and V impurities couple antiferromagnetically, Ru impurities couple ferromagnetically to the host sites. It is shown that the observed composition dependence of the rate of increase of magnetic moment of FexCo1−x alloys upon addition of Mn impurities is due to the change in the magnetic moment of Mn impurities with composition. The reasons for this change and the possibility of stabilizing a higher Mn moment at all concentrations are discussed
Incommensurate Spin Density Waves in Iron Aluminides
Neutron diffraction in Fe(Al) reveals incommensurate spin density waves (SDWs) in alloys known to be spin glasses. The wave vectors for crystals of Fe(34Al), Fe(40Al), and Fe(43Al) show n varying from 11 to 6 for →q=2π(h±1/n,k±1/n,l±1/n)/a0, where (h,k,l) and a0 characterize the parent bcc lattice of the CsCl structure. The magnetic reflections are present far above the spin-glass freezing temperatures. These SDWs keep the spins on nearest-neighbor Fe atoms close to parallel, in contrast with SDWs in Cr, which keep nearest-neighbor spins close to antiparallel
Recommended from our members
Oxidation behavior of molybdenum silicides and their composites
A key materials issue associated with the future of high-temperature structural silicides is the resistance of these materials to oxidation at low temperatures. Oxidation tests were conducted on Mo-based silicides over a wide temperature range to evaluate the effects of alloy composition and temperature on the protective scaling characteristics and testing regime for the materials. The study included Mo{sub 5}Si{sub 3} alloys that contained several concentrations of B. In addition, oxidation characteristics of MoSi{sub 2}-Si{sub 3}N{sub 4} composites that contained 20--80 vol.% Si{sub 3}N{sub 4} were evaluated at 500--1,400 C
Enabling Markets, Trade and Policies for Enhancing Sorghum Uptake
A number of dynamic changes are taking place in the sorghum economies
globally in the last two to three decades both in developed and developing regions
where the crop is grown. In Asia, its use as a staple food crop is declining with a
shift in consumption towards rice and wheat. Rising per capita incomes, urbanization,
change in tastes and preferences are driving this change. However, at the
same time, its demand in alternative uses like poultry feed and potable alcohol
manufacture is growing. In recent years driven by the greater awareness of the
health benefits of sorghum, there is also a growing demand for processed
sorghum products particularly in India for ready to use and eat food
products mainly in urban areas (from a low base). To sustain the change in the
sorghum economies (plate to plough), there is a need to reorient the marketing
system by linking farmers to the end users through innovative institutional
arrangements. Policies should ensure sorghum competitiveness on farm and
directly or indirectly promote its use in food processing and alternative
non-food uses.
In developed countries and in Latin American countries, sorghum is mainly
used as feed but its use is fluctuating and variable depending on its price
competitiveness and policies related to trade in feed crops. In the last one to
two decades with governments mandating use of renewable fuels for blending
with gasoline, sorghum along with maize are being used for ethanol production
that has implications for the livestock sector. Policies related to ethanol production
will have implication for sorghum production and trade
Tuneable magnetic patterning of paramagnetic Fe60Al40 (at. %) by consecutive ion irradiation through pre-lithographed shadow masks
This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.Arrays of ferromagnetic circular dots (with diameters ranging from 225 to 420 nm) have been prepared at the surface of atomically ordered paramagnetic Fe60Al40 (at. %) sheets by means of ion irradiation through prelithographed poly(methyl methacrylate) (PMMA) masks. The cumulative effects of consecutive ion irradiation (using Ar+ ions at 1.2 × 1014 ions/cm2 with 10, 13, 16, 19 and 22 keV incident energies) on the properties of the patterned dots have been investigated. A progressive increase in the overall magneto-optical Kerr signal is observed for increasingly larger irradiation energies, an effect which is ascribed to accumulation of atomic disorder. Conversely, the coercivity, HC, shows a maximum after irradiating at 16-19 keV and it decreases for larger irradiation energies. Such a decrease in HC is ascribed to the formation of vortex states during magnetization reversal, in agreement with results obtained from micromagnetic simulations. At the same time, the PMMA layer, with an initial thickness of 90 nm, becomes progressively thinned during the successive irradiation processes. After irradiation at 22 keV, the remaining PMMA layer is too thin to stop the incoming ions and, consequently, ferromagnetism starts to be generated underneath the nominally masked areas. These experimental results are in agreement with calculations using the Monte-Carlo simulation Stopping Range of Ions in Matter software, which show that for exceedingly thin PMMA layers Ar+ ions can reach the Fe60Al40 layer despite the presence of the mask
Development of a Fully Human Anti-PDGFRβ Antibody That Suppresses Growth of Human Tumor Xenografts and Enhances Antitumor Activity of an Anti-VEGFR2 Antibody
Platelet-derived growth factor receptor β (PDGFRβ) is upregulated in most of solid tumors. It is expressed by pericytes/smooth muscle cells, fibroblast, macrophage, and certain tumor cells. Several PDGF receptor-related antagonists are being developed as potential antitumor agents and have demonstrated promising antitumor activity in both preclinical and clinical settings. Here, we produced a fully human neutralizing antibody, IMC-2C5, directed against PDGFRβ from an antibody phage display library. IMC-2C5 binds to both human and mouse PDGFRβ and blocks PDGF-B from binding to the receptor. IMC-2C5 also blocks ligand-stimulated activation of PDGFRβ and downstream signaling molecules in tumor cells. In animal studies, IMC-2C5 significantly delayed the growth of OVCAR-8 and NCI-H460 human tumor xenografts in nude mice but failed to show antitumor activities in OVCAR-5 and Caki-1 xenografts. Our results indicate that the antitumor efficacy of IMC-2C5 is primarily due to its effects on tumor stroma, rather than on tumor cells directly. Combination of IMC-2C5 and DC101, an anti-mouse vascular endothelial growth factor receptor 2 antibody, resulted in significantly enhanced antitumor activity in BxPC-3, NCI-H460, and HCT-116 xenografts, compared with DC101 alone, and the trend of additive effects to DC101 treatment in several other tumor models. ELISA analysis of NCI-H460 tumor homogenates showed that IMC-2C5 attenuated protein level of vascular endothelial growth factor and basic fibroblast growth factor elevated by DC101 treatment. Finally, IMC-2C5 showed a trend of additive effects when combined with DC101/chemotherapy in MIA-PaCa-2 and NCI-H460 models. Taken together, these results lend great support to the use of PDGFRβ antagonists in combination with other antiangiogenic agents in the treatment of a broad range of human cancers
Simulating Potential Impacts of Future Climate Change on Post-Rainy Season Sorghum Yields in India
Given the wide use of the multi-climate model mean (MMM) for impact assessment studies, this work examines the fidelity of Coupled Model Intercomparison Project Phase 5 (CMIP5) in
simulating the features of Indian summer monsoons as well as the post-rainy seasons for assessing the possible impacts of climate change on post-rainy season sorghum crop yields across India. The MMM simulations captured the spatial patterns and annual cycles of rainfall and surface air temperatures. However, bias was observed in the precipitation amounts and daily rainfall intensity. The trends in the simulations of MMM for both precipitation and temperatures were less satisfactory than the observed climate means. The Crop Environment Resource Synthesis (CERES)-sorghum model was used to estimate the potential impacts of future climate change on post-rainy season sorghum yield values. On average, post-rainy season sorghum yields are projected to vary betwee
Recommended from our members
Rare variant contribution to human disease in 281,104 UK Biobank exomes.
Genome-wide association studies have uncovered thousands of common variants associated with human disease, but the contribution of rare variants to common disease remains relatively unexplored. The UK Biobank contains detailed phenotypic data linked to medical records for approximately 500,000 participants, offering an unprecedented opportunity to evaluate the effect of rare variation on a broad collection of traits1,2. Here we study the relationships between rare protein-coding variants and 17,361 binary and 1,419 quantitative phenotypes using exome sequencing data from 269,171 UK Biobank participants of European ancestry. Gene-based collapsing analyses revealed 1,703 statistically significant gene-phenotype associations for binary traits, with a median odds ratio of 12.4. Furthermore, 83% of these associations were undetectable via single-variant association tests, emphasizing the power of gene-based collapsing analysis in the setting of high allelic heterogeneity. Gene-phenotype associations were also significantly enriched for loss-of-function-mediated traits and approved drug targets. Finally, we performed ancestry-specific and pan-ancestry collapsing analyses using exome sequencing data from 11,933 UK Biobank participants of African, East Asian or South Asian ancestry. Our results highlight a significant contribution of rare variants to common disease. Summary statistics are publicly available through an interactive portal ( http://azphewas.com/ )
- …