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Simulation-based verification of EM side-channel attack resilience of embedded cryptographic systems
Electromagnetic (EM) fields emanated due to switching currents in crypto-blocks can be an effective non-invasive channel for extracting secret keys. Accurate design-time simulation tools are needed to predict vulnerabilities and improve resilience of embedded systems to EM side-channel analysis attacks. Modeling such attacks is challenging, however, as it requires a multitude of expensive simulations across multiple circuit abstraction levels together with EM simulations. In this work, a simulation ow is developed to study the differential EM analysis (DEMA) attack on the Advanced Encryption System (AES) block cipher. The proposed ow enables design-time evaluation of realistic DEMA attacks for the first time. The major challenge is accurately computing signals received by a nearby probe at various positions above the chip surface for a large number of AES encryptions. This requires rapidly generating spatial distribution and transient EM radiation of on-chip current waveforms. Commercial CAD tools are used to generate space-time samples of these waveforms and a custom EM simulator to radiate them. The computations are sped up by focusing on information-leaking time windows, performing hybrid gate- and transistor-level simulations, radiating only the currents on top metallization layers, and generating traces for different encryptions in parallel. These methods reduce simulation time to a manageable ~ 20 hrs wall-clock time/attack allowing a previously impossible level of vulnerability analysis. The proposed ow also allows pinpointing critical regions on the chip most susceptible to EM attacks. We demonstrate that exploiting the spatial profile of circuit elements can reveal cryptographic keys with significantly fewer number of traces than DPA , guiding designers to the most critical areas of the layout. This enables targeted deployment of counter-measures to the highest information-leaking design componentsElectrical and Computer Engineerin
Reactive Oxygen Species and Inhibitors of Inflammatory Enzymes, NADPH Oxidase, and iNOS in Experimental Models of Parkinson's Disease
Reactive oxygen species (ROSs) are emerging as important players in the etiology of neurodegenerative disorders including Parkinson's disease (PD). Out of several ROS-generating systems, the inflammatory enzymes nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and inducible nitric oxide synthase (iNOS) were believed to play major roles. Mounting evidence suggests that activation of NADPH oxidase and the expression of iNOS are directly linked to the generation of highly reactive ROS which affects various cellular components and preferentially damage midbrain dopaminergic neurons in PD. Therefore, appropriate management or inhibition of ROS generated by these enzymes may represent a therapeutic target to reduce neuronal degeneration seen in PD. Here, we have summarized recently developed agents and patents claimed as inhibitors of NADPH oxidase and iNOS enzymes in experimental models of PD
Cohort monitoring of persons with diabetes mellitus in a primary healthcare clinic for Palestine refugees in Jordan.
Objective To illustrate the method of cohort reporting of persons with diabetes mellitus (DM) in a primary healthcare clinic in Amman, Jordan, serving Palestine refugees with the aim of improving quality of DM care services. Method A descriptive study using quarterly and cumulative case findings, as well as cumulative and 12-month analyses of cohort outcomes collected through E-Health in UNRWA Nuzha Primary Health Care Clinic. Results There were 55 newly registered patients with DM in quarter 1, 2012, and a total of 2851 patients with DM ever registered on E-Health because this was established in 2009. By 31 March 2012, 70% of 2851 patients were alive in care, 18% had failed to present to a healthcare worker in the last 3 months and the remainder had died, transferred out or were lost to follow-up. Cumulative and 12-month cohort outcome analysis indicated deficiencies in several components of clinical care: measurement of blood pressure, annual assessments for foot care and blood tests for glucose, cholesterol and renal function. 10-20% of patients with DM in the different cohorts had serious late complications such as blindness, stroke, cardiovascular disease and amputations. Conclusion Cohort analysis provides data about incidence and prevalence of DM at the clinic level, clinical management performance and prevalence of serious morbidity. It needs to be more widely applied for the monitoring and management of non-communicable chronic diseases
Dentinogenic Ghost Cell Tumor of the Peripheral Variant Mimicking Epulis
Dentinogenic ghost cell tumor (DGCT) is an uncommon locally invasive odontogenic tumor regarded by many as a variant of calcifying odontogenic cyst. The peripheral variant of this clinical rarity appears as a well-circumscribed mass mimicking a nonspecific gingival enlargement. Microscopic appearance of odontogenic epithelium admixed with focal areas of dentinoid formation and sheets of ghost cells giving the definitive diagnosis of dentinogenic ghost cell tumor imply that microscopic examination is compulsory for any gingival mass. Van Gieson histochemical stain further confirmed the nature of dentinoid-like material. A complete workup of a case of peripheral dentinogenic ghost cell tumor is presented in this paper and the current concept as well as the appraisal of literature is presented
Effect of Short Chain Branching on the Interlamellar Structure of Semicrystalline Polyethylene
We use molecular simulations with a united atom force field to examine the effect of short chain branching (SCB) on the noncrystalline, interlamellar structure typical of linear low density polyethylene (LLDPE). The model is predicated on a metastable thermodynamic equilibrium within the interlamellar space of the crystal stack and accounts explicitly for the various chain topologies (loops, tails, and bridges) therein. We examine three branched systems containing methyl, ethyl, and butyl side branches and compare our results to high density polyethylene (HDPE), without branches. We also compare results for two united atom force fields, PYS and TraPPE-UA, within the context of these simulations. In contrast to conventional wisdom, our simulations indicate that the thicknesses of the interfacial regions in systems with SCB are smaller than those observed for a linear polyethylene without branches and that branches are uniformly distributed throughout the interlamellar region. We find a prevalence of gauche states along the backbone due to the presence of branches and an abrupt decrease in the orientational order in the region immediately adjacent to the crystallite
Concept-Driven Visual Analytics: an Exploratory Study of Model- and Hypothesis-Based Reasoning with Visualizations
Visualization tools facilitate exploratory data analysis, but fall short at supporting hypothesis-based reasoning. We conducted an exploratory study to investigate how visualizations might support a concept-driven analysis style, where users can optionally share their hypotheses and conceptual models in natural language, and receive customized plots depicting the fit of their models to the data. We report on how participants leveraged these unique affordances for visual analysis. We found that a majority of participants articulated meaningful models and predictions, utilizing them as entry points to sensemaking. We contribute an abstract typology representing the types of models participants held and externalized as data expectations. Our findings suggest ways for rearchitecting visual analytics tools to better support hypothesis- and model-based reasoning, in addition to their traditional role in exploratory analysis. We discuss the design implications and reflect on the potential benefits and challenges involved.National Science Foundation award #175561
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