Oxidative susceptibility of low density lipoprotein from rabbits fed atherogenic diets containing coconut,palm, or soybean oils

The oxidative susceptibilities of low density lipoproteins (LDL) isolated from rabbits fed high-fat atherogenic diets containing coconut, palm, or soybean oils were investigated. New Zealand white rabbits were fed atherogenic semisynthetic diets containing 0.5% cholesterol and either (i) 13% coconut oil and 2% corn oil (CNO), (ii) 15% refined, bleached, and deodorized palm olein (RBDPO), (iii) 15% crude palm olein (CPO), (iv) 15% soybean oil (SO), or (v) 15% refined, bleached, and deodorized palm olein without cholesterol supplementation [RBDPO(wc)], for a period of twelve weeks. Total fatty acid compositions of the plasma and LDL were found to be modulated (but not too drastically) by the nature of the dietary fats. Cholesterol supplementation significantly increased the plasma level of vitamin E and effectively altered the plasma composition of long-chain fatty acids in favor of increasing oleic acid. Oxidative susceptibilities of LDL samples were determined by Cu²⁺-catalyzed oxidation which provide the lag times and lag-phase slopes. The plasma LDL from all palm oil diets [RBDPO, CPO, and RBDPO(wc)] were shown to be equally resistant to the oxidation, and the LDL from SO-fed rabbits were most susceptible, followed by the LDL from the CNO-fed rabbits. These results reflect a relationship between the oxidative susceptibility of LDL due to a combination of the levels of polyun-saturated fatty acids and vitamin E. Based on a paper presented at the PORIM International Palm Oil Congress (PIPOC) held in Kuala Lumpur, Malaysia, 1993.     

Operating characteristics of InGaAs-GaAs MQW hetero-nipi waveguidemodulators

We report frequency response measurements of optical MQW nipi waveguide modulators, observing a -3-dB bandwidth as high as 110 MHz. These devices have only 900-Å-thick intrinsic regions, and thus can achieve very high fields with modest reverse bias voltages. We also measured absorption modulation (32 dB) and a phase change figure of merit as low as V_π×L=0.8 V mm at a detuning of 115 meV below the photoluminescence peak. We compare ion-implanted selective contacts with traditional selective metal contacts     

Electrochemical studies on doping of polyacetylene

The mechanism for electrochemical doping of polyacetylene was studied using cyclic voltammetry. The I–V curve of a thin (CH)_x filme (<1 μm) electrode exhibited a redox peak with a formal redox potential of +0.65 V vs. sodium calomel electrode. Approximately 30% of the total charge that oxidized (CH)_x was not reversible when held at the open circuit voltage of the cell. A more negative potential was needed to recover the remaining charge. This large charge-trapping phenomenon was the consequence of the (CH)_x film being doped. Using a thick film (?50 μm) electrode or freestanding film (～0.1 mm) as an electrode, the I–V curve gave only a broad re-reduction peak at +0.4 V. The disappearance of the well-defined redox peak implies that the redox process revealed by the thin film data may not be the predominate mechanism for the doping process.     

Accelerating number theoretic transform in GPU platform for fully homomorphic encryption

The Journal of Supercomputing - In scientific computing and cryptography, there are many applications that involve large integer multiplication, which is a time-consuming operation. To reduce the...     

A review on recent status and challenges of yttria stabilized zirconia modification to lowering the temperature of solid oxide fuel cells operation

Solid Oxide Fuel Cells (SOFCs) are an electrochemical energy converter that receives the world's attention as a power generation system of the future owing to its flexibility to consume various types of fuels, low emission of greenhouses gases, and having high efficiency reaching over 70%. A conventional SOFCs operates at high temperature, typically ranges between 800 to 1000°C. SOFCs use yttria-stabilized zirconia (YSZ) as the electrolyte, which exhibits excellent oxide ion conductivity in this temperature range. However, this temperature range poses an issue to SOFCs durability, as it leads to the degradation of the cell components. In addition, SOFCs application is limited and difficult to implement for the transportation sector and portable appliance. A viable solution is to lower the SOFCs operating temperature to intermediate (600 to 800°C) or low (<600°C) operating temperature. The benefit of this way, cell durability will improve, as well as other advantages such as facilitates handling, assembling, dismantling, cost reduction, and expanded the SOFCs application. Nonetheless, the key challenge for the issue is finding suitable electrolyte, as YSZ have lower ionic conductivity at low and intermediate temperature range. The aim of this paper is to review the status and challenges in the attempts made to modify YSZ electrolyte within the past decade. The resulting ionic conductivity, microstructure, and densification, mechanical and thermal properties of these 'new' electrolytes critically reviewed. The targeted conductivity of modification of YSZ electrolyte must be exceeded >0.1 S cm^–1 to enable high performance of SOFCs power generation systems to be realized for transportation and portable applications. Based on our knowledge, this paper is the first review which focused on the recent status and challenges of YSZ electrolyte towards lowering the operating temperature.     

Experimental investigations of the revolving vane (RV-I) expander

A novel revolving vane (RV-I) expander prototype, where the vane is rigidly attached to the rotor and the cylinder is allowed to move together with the rotor, has been built and studied experimentally. The prototype is found to operate successfully in the range of operating conditions tested: speed of up to 600 rpm and suction pressure of up to 5 barg. At the designed suction pressure of 3 barg, the isentropic and volumetric efficiency of the prototype is found to be up to 32% and 25% respectively. The data are found to be in good agreement with the theoretical predictions with standard deviations of less than 10% for most of the average torque and flow rate data points. The theoretical model is also found to be able to accurately predict the instantaneous torque of the expander.     

In situ observation of size-scale effects on the mechanical properties of ZnO nanowires

In this investigation, the size-scale in mechanical properties of individual [0001] ZnO nanowires and the correlation with atomic-scale arrangements were explored via in situ high-resolution transmission electron microscopy (TEM) equipped with atomic force microscopy (AFM) and nanoindentation (NI) systems. The Young's modulus was determined to be size-scale-dependent for nanowires with diameter, d, in the range of 40 nm ≤ d ≤ 110 nm, and reached the maximum of ～ 249 GPa for d = 40 nm. However, this phenomenon was not observed for nanowires in the range of 200 nm ≤ d ≤ 400 nm, where an average constant Young's modulus of ～ 147.3 GPa was detected, close to the modulus value of bulk ZnO. A size-scale dependence in the failure of nanowires was also observed. The thick ZnO nanowires (d ≥ 200 nm) were brittle, while the thin nanowires (d ≤ 110 nm) were highly flexible. The diameter effect and enhanced Young's modulus observed in thin ZnO nanowires are due to the combined effects of surface relaxation and long-range interactions present in ionic crystals, which leads to much stiffer surfaces than bulk wires. The brittle failure in thicker ZnO wires was initiated from the outermost layer, where the maximum tensile stress operates and propagates along the (0001) planes. After a number of loading and unloading cycles, the highly compressed region of the thinner nanowires was transformed from a crystalline to an amorphous phase, and the region near the neutral zone was converted into a mixture of disordered atomic planes and bent lattice fringes as revealed by high-resolution images.     

ZnO nanosquids: branching nanowires from nanotubes and nanorods

One-dimensional (1D) semiconductor nanostructures are promising building blocks for future nanoelectronic and nanophotonic devices. ZnO has proven to be a multifunctional and multistructural nanomaterial with promising properties. Here we report the growth of ZnO nanosquids which can be directly grown on planar oxidized Si substrates without using catalysts and templates. The formation of these nanosquids can be explained by the theory of nucleation, and the vapor-solid crystal growth mechanism. The branching nanowires of these ZnO nanosquids could have potential application in multiplexing future nanoelectronic devices. The sharp band-edge emission at approximately 380 nm indicates that these ZnO nanosquids are also applicable for interesting optoelectronic devices.