North Carolina State University

About: North Carolina State University is a education organization based out in Raleigh, North Carolina, United States. It is known for research contribution in the topics: Population & Thin film. The organization has 44161 authors who have published 101744 publications receiving 3456774 citations. The organization is also known as: NCSU & North Carolina State University at Raleigh.

Tomatoes and cardiovascular health.

Abstract: Diet is believed to play a complex role in the development of cardiovascular disease, the leading cause of death in the Western world. Tomatoes, the second most produced and consumed vegetable nationwide, are a rich source of lycopene, beta-carotene, folate, potassium, vitamin C, flavonoids, and vitamin E. The processing of tomatoes may significantly affect the bioavailability of these nutrients. Homogenization, heat treatment, and the incorporation of oil in processed tomato products leads to increased lycopene bioavailability, while some of the same processes cause significant loss of other nutrients. Nutrient content is also affected by variety and maturity. Many of these nutrients may function individually, or in concert, to protect lipoproteins and vascular cells from oxidation, the most widely accepted theory for the genesis of atherosclerosis. This hypothesis has been supported by in vitro, limited in vivo, and many epidemiological studies that associate reduced cardiovascular risk with consumption of antioxidant-rich foods. Other cardioprotective functions provided by the nutrients in tomatoes may include the reduction of low-density lipoprotein (LDL) cholesterol, homocysteine, platelet aggregation, and blood pressure. Because tomatoes include several nutrients associated with theoretical or proven effects and are widely consumed year round, they may be considered a valuable component of a cardioprotective diet.

Native defects in gallium nitride

Abstract: The results of an extensive theoretical study of native defects in hexagonal GaN are presented. We have considered cation and anion vacancies, antisites, and interstitials. The computations were carried out using ab initio molecular dynamics in supercells containing 72 atoms. N vacancy introduces a shallow donor level, and may be responsible for the n-type character of as-grown GaN. Due to the wide gap of nitrides, self-compensation effects strongly reduce both n-type and p-type doping efficiencies due to the formation of gallium vacancy and interstitial Ga, respectively.

HyperSafe: A Lightweight Approach to Provide Lifetime Hypervisor Control-Flow Integrity

Abstract: Virtualization is being widely adopted in today’s computing systems. Its unique security advantages in isolating and introspecting commodity OSes as virtual machines (VMs) have enabled a wide spectrum of applications. However, a common, fundamental assumption is the presence of a trustworthy hypervisor. Unfortunately, the large code base of commodity hypervisors and recent successful hypervisor attacks (e.g., VM escape) seriously question the validity of this assumption. In this paper, we present HyperSafe, a lightweight approach that endows existing Type-I bare-metal hypervisors with a unique self-protection capability to provide lifetime control flow integrity. Specifically, we propose two key techniques. The first one, non-bypassable memory lockdown, reliably protects the hypervisor’s code and static data from being compromised even in the presence of exploitable memory corruption bugs (e.g., buffer overflows), therefore successfully providing hypervisor code integrity. The second one, restricted pointer indexing, introduces one layer of indirection to convert the control data into pointer indexes. These pointer indexes are restricted such that the corresponding call/return targets strictly follow the hypervisor control flow graph, hence expanding protection to control-flow integrity. We have built a prototype and used it to protect two open-source Type-I hypervisors: BitVisor and Xen. The experimental results with synthetic hypervisor exploits and benchmarking programs show HyperSafe can reliably enable the hypervisor self-protection and provide the integrity guarantee with a small performance overhead.

Giant piezoelectricity of Sm-doped Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystals.

Abstract: High-performance piezoelectrics benefit transducers and sensors in a variety of electromechanical applications. The materials with the highest piezoelectric charge coefficients (d33) are relaxor-PbTiO3 crystals, which were discovered two decades ago. We successfully grew Sm-doped Pb(Mg1/3Nb2/3)O3-PbTiO3 (Sm-PMN-PT) single crystals with even higher d33 values ranging from 3400 to 4100 picocoulombs per newton, with variation below 20% over the as-grown crystal boule, exhibiting good property uniformity. We characterized the Sm-PMN-PT on the atomic scale with scanning transmission electron microscopy and made first-principles calculations to determine that the giant piezoelectric properties arise from the enhanced local structural heterogeneity introduced by Sm3+ dopants. Rare-earth doping is thus identified as a general strategy for introducing local structural heterogeneity in order to enhance the piezoelectricity of relaxor ferroelectric crystals.