Hardware Implementation of Successive-Cancellation Decoders for Polar Codes

The recently-discovered polar codes are seen as a major breakthrough in coding theory; they provably achieve the theoretical capacity of discrete memoryless channels using the low-complexity successive cancellation decoding algorithm. Motivated by recent developments in polar coding theory, we propose a family of efficient hardware implementations for successive cancellation (SC) polar decoders. We show that such decoders can be implemented with O(N) processing elements and O(N) memory elements. Furthermore, we show that SC decoding can be implemented in the logarithmic domain, thereby eliminating costly multiplication and division operations, and reducing the complexity of each processing element greatly. We also present a detailed architecture for an SC decoder and provide logic synthesis results confirming the linear complexity growth of the decoder as the code length increases.     

Metabolic Remodeling with Hepatosteatosis Induced Vascular Oxidative Stress in Hepatic ERK2 Deficiency Mice with High Fat Diets

We previously demonstrated the marked hepatosteatosis and endothelial dysfunction in hepatocyte-specific ERK2 knockout mice (LE2KO) with a high-fat/high-sucrose diet (HFHSD), but detailed metabolic changes and the characteristics in insulin-sensitive organs were not tested. This study aimed to characterize metabolic remodeling with changes in insulin-sensitive organs, which could induce endothelial dysfunction in HFHSD-LE2KO. The serum glucose and fatty acid (FA) were modestly higher in HFHSD-LE2KO than HFHSD-Control. FA synthesis genes were up-regulated, which was associated with the decreased phosphorylation of AMPK and ACC, and with the up-regulation of SREBP-1 in the liver from HFHSD-LE2KO. In FA and amino acids fraction analysis, arachidonic acid/eicosapentaenoic acid ratio, L-ornithine/arginine ratio, asymmetric dimethylarginine and homocysteine levels were elevated in HFHSD-LE2KO. Insulin-induced phosphorylation of AKT was blunted in skeletal muscle. Serum leptin and IL-1β were elevated, and serum adiponectin was decreased with the enlargement of epididymal adipocytes. Finally, the enhanced superoxide levels in the aorta, which were blunted with CCCP, apocynin, and tempol, were observed in HFHSD-LE2KO. A pre-incubation of aortic rings with tempol improved endothelial dysfunction in HFHSD-LE2KO. HFHSD-LE2KO revealed an acceleration of FA synthesis in the liver leading to insulin resistance in skeletal muscle and the enlargement of visceral adipocytes. Global metabolic remodeling such as changes in arginine metabolism, ω3/ω6 ratio, and adipocytokines, could affect the vascular oxidative stress and endothelial dysfunction in HFHSD-LE2KO.     

Intergroup competition for public goods: Effects of unequal resources and relative group size.

Studied single-stage intergroup competition for public goods in small groups with total resources of equal size and binary contributions. In Experiment 1, the two competing groups were of equal size, but the individual resources (endowments) within each group differed from one member to another. The main finding was a negative relation between the endowment size and the likelihood of contribution. In Experiment 2, the ratio of public good to endowment was the same for all members of both groups, but sizes of the groups were unequal. We found no effect of group size per se on level of contribution. Theoretical and methodological implication of the findings are briefly discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of chemotherapy on FDG uptake by human cancer xenografts in nude mice

This study evaluated the use of PET with 18F-2-deoxy-2-fluoro-D-glucose (18F-FDG) for monitoring chemotherapy effects, using a human cancer xenograft (poorly differentiated human gastric cancer) in vivo model. METHODS: Tumor 18F-FDG uptakes and sizes were measured after administrating mitomycin (MMC), cisplatin (CDDP) and adriamycin (ADR) to xenograft-bearing nude mice and compared with 18F-FDG tumor uptake and tumor size in a non-therapy group. The correlation between the uptake and size was also assessed. RESULTS: The largest reduction in tumor size after chemotherapy occurred in the MMC administered group, followed by the CDDP case, with no reduction in the ADR group as compared to the controls. Fluorine-18-FDG tumor uptake after chemotherapy was also decreased in the MMC and CDDP groups, in that order, but not in the ADR case. With MMC and CDDP, size reduction became significant on Days 8 or 11, whereas 18F-FDG tumor uptake had already been decreased on Days 3 or 7. CONCLUSION: Fluorine-18-FDG uptake decreases in parallel to the efficacy of anticancer agents and correlates with subsequent morphologic changes. We conclude that 18F-FDG PET tumor images are indeed useful for monitoring the effects of cancer chemotherapy.     

Personal supercomputing by using transputer and Intel 80860 in plasma engineering

Transputer (T800) and 64-bit RISC Intel 80860 (i860) added on a personal computer can be used as an accelerator. When 32-bit T800s in a parallel system or 64-bit i860s are used, scientific calculations are carried out several ten times as fast as in the case of commonly used 32-bit personal computers or UNIX workstations. Benchmark tests and examples of physical simulations using T800s and i860 are reported.     

Spin susceptibility of La2−xSrxCuO4; Modification of localized character of Cu 3d-Electrons at x≳0.15

The magnetic susceptibility X of superconducting La_2–xSr_xCuO₄ (LSCO) was investigated over a wide x-range. The effective magnetic moment on the Cu-site of LSCO is progressively suppressed at x0.15 owing to deterioration of the localized character of Cu 3d-electrons, and the superconducting transition temperature T_c begins to decrease near x=0.15. The density of states at the Fermi level, estimated from the electronic specific heat or the T-independent spin part of X, is enhanced above x 0.15.     

Neutronic optimization for a blanket of the laser fusion reactor,SENRI-I

Neutronic calculations were performed to optimize the SENRI blanket in terms of energy multiplication as well as tritium breeding ratio. The blanket employs a thick ( 64-cm) Li layer as breeder/coolant. Three approaches were taken here to achieve the goal: (1) reduction of⁶Li in the lithium, (ii) replacement of the Li layer by a molten-salt (flibe) layer, and (iii) shipment of excess tritium to a nonbreeding blanket. It was found that the excess tritium produced in the SENRI blanket could be used effectively to obtain additional power by fueling a nonbreeding D-T reactor.     

Experimental realization of an imaging system with an extended depth of field

We describe the experimental realization of an all-optical imaging system with an extended depth of field (DOF). The core of the system is a phase mask consisting of 16 Fresnel lenses (FLs) that are spatially multiplexed and mutually exclusive. Because each FL, in tandem with the primary lens, is designed to produce a sharp image for a specific object plane location, jointly the FLs achieve a wide DOF. However, the resultant image exhibits reduced resolution. The acquired image, onto which we did not apply any postprocessing, clearly is sharper than that acquired with a clear-aperture imaging system with the same pupil size.     

Designing a regenerable stimuli-responsive grafted polymer-clay sorbent for filtration of water pollutants

A novel, stimuli-responsive composite, based on poly(4-vinylpyridine) (PVP) brushes, end-grafted to montmorillonite clay (GPC), was designed as a regenerable sorbent for efficient removal of pollutants from water. We characterized the novel composite sorbent and its response to pH, employing Fourier transform infrared, X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetry analysis and zeta potential measurements. In comparison with conventional, electrostatically adsorbed PVP composites (APC), the GPC presented superior characteristics: higher polymer loading without polymer release, higher zeta potential and lower pH/charge dependency. These superior characteristics explained the significantly higher removal of organic and inorganic anionic pollutants by this composite, in comparison with the removal by APC and by many reported sorbents. For example, the filtration (20 pore volumes) of selenate by GPC, APC and a commercial resin column was complete (100%), negligible (0%) and reached 90% removal, respectively. At low–moderate pH, the grafted polymer undergoes protonation, promoting pollutant adsorption, whereas at high pH, the polymer deprotonates, promoting pollutant desorption. Indeed, ‘in-column’ regeneration of the GPC sorbents was achieved by increasing pH, and upon a second filtration cycle, no reduction in filter capacity was observed. These findings suggest the possible applicability of this stimuli-responsive sorbent for water treatment.