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41.
We study quantum effects in a system of S = 1/2 spins with two–, three and four–spin exchange interactions on the triangular lattice, a possible model of the nuclear magnetism of solid
3
He layers. The ground state phases found in our previous work are studied by using the linear spin–wave theory. The uuud state shows a very flat spin–wave dispersion, which suggests that this state, though locally stable, will not survive non–linear quantum effects. The tetrahedral state, which has long–range order of a scalar chirality, is found to be stable against spin wave fluctuations. The ground state energies of different phases are compared. Results of numerical analysis of finite size clusters are also presented. 相似文献
42.
43.
Kikuta K Tochigi N Saito S Shimoda T Morioka H Toyama Y Hosono A Suehara Y Beppu Y Kawai A Hirohashi S Kondo T 《Proteomics. Clinical applications》2010,4(5):560-567
Purpose : We aimed to identify novel chemotherapy responsiveness biomarkers for osteosarcoma (OS) by investigating the global protein expression profile of 12 biopsy samples from OS patients. Experimental design : Six patients were classified as good responders and six as poor responders, according to the Huvos grading system. The protein expression profiles obtained by 2‐D DIGE consisted of 2250 protein spots. Results : Among them, we identified 55 protein spots whose intensity was significantly different (Bonferroni adjusted p‐value<0.01) between the two patient groups. Mass spectrometric protein identification demonstrated that the 55 spots corresponded to 38 distinct gene products including peroxiredoxin 2 (PRDX 2). Use of a specific antibody against PRDX 2 confirmed the differential expression of PRDX 2 between good and poor responders, while PRDX 2 levels as measured by Western blotting correlated highly with their corresponding 2‐D DIGE values. The predictive value of PRDX 2 expression was further confirmed by examining an additional four OS cases using Western blotting. Conclusions and clinical relevance : These results establish PRDX 2 as a candidate for chemotherapy responsiveness marker in OS. Measuring PRDX 2 in biopsy samples before treatment may contribute to more effective management of OS. 相似文献
44.
Yasuo Ariki 《New Generation Computing》2000,18(4):341-357
Because of the media digitization, a large amount of information such as speech, audio and video data is produced everyday.
In order to retrieve data from these databases quickly and precisely, multimedia technologies for structuring and retrieving
of speech, audio and video data are strongly required. In this paper, we overview the multimedia technologies such as structuring
and retrieval of speech, audio and video data, speaker indexing, audio summarization and cross media retrieval existing today
for TV news detabase. The main purpose of structuring is to produce tables of contents and indices from audio and video data
automatically. In order to make these technologies feasible, first, processing units such as words on audio data and shots
on video data are extracted. On a second step, they are meaningfully integrated into topics. Furthermore, the units extracted
from different types of media are integrated for higher functions.
Yasuo Ariki, Ph.D.: He is a Professor in the Department of Electronics and Informatics at the Ryukoku University. He received his B.E., M.E.
and Ph.D. in information science from Kyoto University in 1974, 1976 and 1979, respectively. He had been an Assistant in Kyoto
University from 1980 to 1990, and stayed at Edinburgh University as visiting academic from 1987 to 1990. His research interests
are in speech and image recognition and in information retrieval and database. He is a member of IPSJ, IEICE, ASJ, Soc. Artif.
Intel. and IEEE. 相似文献
45.
Kusaka T Ueno M Miki T Kanenishi K Nagai Y Huang CL Okamoto Y Ogawa T Onodera M Itoh S Akiguchi I Sakamoto H 《Microscopy research and technique》2007,70(7):648-655
We investigated whether beta-amyloid (Abeta)-like immunoreactivity was seen in the brains of newborn piglets. The immunoreactivity for Abeta(1-42) and Abeta(1-40) proteins, but not Abeta precursor protein, was present in CD68-positive perivascular cells of the hippocampus and in parts of the meninges. It was colocalized with immunoreactivity for receptor for advanced glycation end product and tumor necrosis factor-alpha. The protein with a molecular mass of 27 kDa, which was recognized by the Abeta antibodies, was identified as triosephosphate isomerase (TPI) with sequence homology to Abeta peptides by N-terminal amino acid sequencing, mass fingerprint analysis using matrix-associated laser desorption/ionization mass spectrometry, and Western blotting. Western blotting assay also revealed that detectable expression of Abeta proteins were not seen in the piglet brains. These findings indicate that TPI with sequence homology to Abeta peptides accumulates in perivascular cells of the microglia/macrophage lineage located around arterial vessels of the newborn piglet hippocampus. 相似文献
46.
Yasuo Kinouchi Shoji Inabayashi Akira Satou Fumitoshi Shouji S. Inabayashi 《Artificial Life and Robotics》2000,4(2):53-56
To construct a “thinking-like” processing system, a new architecture of an adaptive associative memory system is proposed.
This memory system treats “images” as basic units of information, and adapts to the environment of the external world by means
of autonomous reactions between the images. The images do not have to be clear, distinct symbols or patterns; they can be
ambiguous, indistinct symbols or patterns as well. This memory system is a kind of neural network made up of nodes and links
called a localist spreading activation network. Each node holds one image in a localist manner. Images in high-activity nodes
interact autonomously and generate new images and links. By this reaction between images, various forms of images are generated
automatically under constraints of links with adjacent nodes. In this system, three simple image reaction operations are defined.
Each operation generates a new image by combining pseudofigures or features and links of two images.
This work was presented, in part, at the Fourth International Symposium on Artificial Life and Robotics, Oita, Japan, January
19–22, 1999 相似文献
47.
48.
Adsorption isotherms of pigments from alkali-refined vegetable oils with clay minerals 总被引:1,自引:0,他引:1
Keito Boki Moriaki Kubo Naohito Kawasaki Hidehito Mori 《Journal of the American Oil Chemists' Society》1992,69(4):372-378
Adsorption isotherms of pigments from alkali-refined oils (rapeseed, soybean, wheatgerm, safflower, corn, cottonseed and sunflower)
were measured to investigate the applicability of the Langmuir and Freundlich equations and to elucidate the adsorption characteristics
of pigments on sepiolites and standard activated clay. The Freundlich equation was more applicable to the experimental adsorption
isotherms. The equilibrium amount adsorbed, acidity, pore size distribution and inflection of the Freundlich isotherms could
be explained by assuming that pigments were adsorbed on the stronger acid sites in smaller pores at low concentration, and
then in the larger ones when the concentration increased. The amount adsorbed increased with a rise in adsorption temperatures
from 70 to 110°C, and the heat of adsorption was below 10 kcal/mol. The results indicate that pigments were physically adsorbed
on the acid sites activated at higher adsorption temperatures. 相似文献
49.
Islam Z Capatina D Ruff JP Das RK Trakhtenberg E Nojiri H Narumi Y Welp U Canfield PC 《The Review of scientific instruments》2012,83(3):035101
We present a pulsed-magnet system that enables x-ray single-crystal diffraction in addition to powder and spectroscopic studies with the magnetic field applied on or close to the scattering plane. The apparatus consists of a single large-bore solenoid, cooled by liquid nitrogen. A second independent closed-cycle cryostat is used for cooling samples near liquid helium temperatures. Pulsed magnetic fields close to ~30 T with a zero-to-peak-field rise time of ~2.9 ms are generated by discharging a 40 kJ capacitor bank into the magnet coil. The unique characteristic of this instrument is the preservation of maximum scattering angle (~23.6°) on the entrance and exit sides of the magnet bore by virtue of a novel double-funnel insert. This instrument will facilitate x-ray diffraction and spectroscopic studies that are impractical, if not impossible, to perform using split-pair and narrow-opening solenoid magnets. Furthermore, it offers a practical solution for preserving optical access in future higher-field pulsed magnets. 相似文献
50.
Thin SiO2 layers were deposited by atomic layer deposition (ALD) using either Bis-dimethylamino-silane (BDMAS: SiH2(N(CH3)2)2) or Tris-dimethylamino-silane (TDMAS: SiH(N(CH3)2)3) precursors. The purpose of this study is to evaluate these precursors for their suitability for ALD of hafnium (Hf)-silicate gate dielectrics. The advantages of these precursors are that the melting points and vapor pressures are moderate. The thickness of SiO2 deposited using ALD process is controlled by the number of growth cycles and the growth rate was different for each precursor, that for BDMAS being 1.5 times that for TDMAS at the same reactor pressure. The carbon impurity in the SiO2 film deposited using BDMAS was about half an order of magnitude less than that using for TDMAS. Furthermore, the carbon impurity was reduced to about the detection limit of secondary ion mass spectrometry after high temperature annealing at 1000 °C during 5 s. 相似文献