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排序方式: 共有575条查询结果,搜索用时 15 毫秒
1.
N Okada S Sato T Sasou M Aoyama K Nishida K Yoshikawa 《Canadian Metallurgical Quarterly》1993,129(4):403-407
Ambiguous abdominal situs, asplenia/polysplenia and severe cardiac malformations characterize heterotaxy in humans. These anomalies result from the inability of the developing embryo to establish normal left-right asymmetry. We have studied an interesting family in which the heterotaxy phenotype segregates as an X-linked recessive trait. In order to map the heterotaxy locus (HTX), we have analysed 39 family members using highly-polymorphic microsatellite markers from the X chromosome. One of these markers, DXS994, shows no recombination with the disease locus in 20 informative meioses. Linkage analysis results in a maximum lod score of 6.37. Current genetic and physical mapping data assign the order of loci in Xq24-q27.1 as cen-DXS1001-(DXS994, HTX)-DXS984-tel. These results establish the first mapping assignment of situs abnormalities in humans. 相似文献
2.
A 40-year-old man with epidermodysplasia verruciformis showed a decrease in peripheral blood T cells and abnormal expansion of large granular lymphocytes, accompanied by increased natural killer cell activity. Surface marker analysis of his large granular lymphocytes demonstrated that the subset, CD 57+ and CD 16+, had increased. His father, who had no skin lesions of epidermodysplasia verruciformis, displayed similar blood changes and his brother showed a decrease in T cells and a slight increase in CD 16+ natural killer cells, whereas his mother revealed only a slight decrease in T cells. Our present study indicates that epidermodysplasia verruciformis might be associated with hereditary abnormal expansion of large granular lymphocytes and a decrease in T cells. 相似文献
3.
Mimura A. Kawachi G. Aoyama T. Suzuki T. Nagae Y. Konishi N. Mochizuki Y. 《Electron Devices, IEEE Transactions on》1993,40(3):513-520
A bucket-type high-density (0.25-1.2-mA/cm2) low-energy (500-2000 V) ion source was utilized for high-speed phosphorus doping directly into a thin polysilicon layer without cap SiO2. Doping gas with He dilution was selected to reduce etching of polysilicon film. Excimer laser (XeCl, 8 mm×8 mm) pulse annealing was introduced to activate effectively the doped impurity. The combination of these techniques provided a practically low sheet resistance for the TFT source, drain, and gate with a short time doping. The low-temperature polysilicon TFT fabricated with a doping time of 10 s had characteristics comparable to those of that fabricated by a longer time doping or conventional ion implantation, showing the practicality of this technology and its promise for giant microelectronics 相似文献
4.
Hiroyuki Miki Takanori Takeno Toshiyuki Takagi Alexei Bozhko Mikhail Shupegin Hideya Onodera Takao Komiyama Takashi Aoyama 《Diamond and Related Materials》2006,15(11-12):1898
Superconductivity in a tungsten-containing carbon-oxide film was reported. The film with 500 nm thickness was deposited onto polycrystalline silicon oxides using chemical vapor deposition and the co-sputtering of a tungsten metal target. The bonding state of the carbon atoms and the macroscopic and microscopic crystal structure of the film were investigated by Raman spectroscopy, X-ray diffraction and transmission electron microscopy measurements. From the experimental results, we determined that this film essentially had an amorphous structure. The temperature dependence on resistivity was measured in the temperature range of 2–300 K. Resistive superconducting transition was observed at 3.8 K. The dc magnetizations were measured in the temperature range of 1.8–6.5 K. The diamagnetism resulting from a superconductive state was observed below 3.75 K, which is consistent with a resistive superconducting transition. It is thought that the finite sized clusters of the different superconductive transition temperatures cooperatively produce a macroscopic superconducting phenomenon. 相似文献
5.
6.
Based on an analogy between thermodynamics and Bayesian inference,inverse halftoning was formulated using multiple halftone images based on Bayesian inference using the maximizer of the posterior marginal(MPM) estimate.Applying Monte Carlo simulation to a set of snapshots of the Q-Ising model,it was demonstrated that optimal performance is achieved around the Bayes-optimal condition within statistical uncertainty and that the performance of the Bayes-optimal solution is superior to that of the maximum-a-posteriori(MAP) estimation which is a deterministic limit of the MPM estimate.These properties were qualitatively confirmed by the mean-field theory using an infinite-range model established in statistical mechanics.Additionally,a practical and useful method was constructed using the statistical mechanical iterative method via the Bethe approximation.Numerical simulations for a 256-grayscale standard image show that Bethe approximation works as good as the MPM estimation if the parameters are set appropriately. 相似文献
7.
Yusuke Soraji Kazuo Furuta Taro Kanno Hisae Aoyama Satoru Inoue Daisuke Karikawa Makoto Takahashi 《Cognition, Technology & Work》2012,14(2):93-105
Since controller teams are in charge of en-route air traffic control, team cooperation is a key issue for good control performance. We conducted ethnographic field observation at the Tokyo Area Control Center and then analyzed the obtained data to develop a cognitive model of team cooperation in en-route air traffic control. We segmented conversational records, behavioral records, and so on by control unit, and then clarified relations between the segments and identified expert knowledge and judgment behind them. Cognitive processes of controller teams were reconstructed based on a concept of distributed cognition. The analysis revealed that the mutual belief model is applicable to team cooperation processes, the role assignment of tasks within a controller team is implicit and that control plans are implemented smoothly once team situation awareness has been established. A cognitive model of controllers?? team cooperation has been constructed based on these findings. 相似文献
8.
Extraction and implementation of muscle synergies in neuro-mechanical control of upper limb movement
Hang Pham Yohei Ariga Kenta Tominaga Takanori Oku Kanna Nakayama Mitsunori Uemura 《Advanced Robotics》2014,28(11):745-757
This work faces the redundancy problem, a central concern in robotics, in a particular force-producing task by using muscle synergies to simplify the control. We extracted muscle synergies from human electromyograph signals and interpreted the physical meaning of the identified muscle synergies. Based on the human analysis results, we hypothesized a novel control framework that can explain the mechanism of the human motor control. The framework was tested in controlling a pneumatic-driven robotic arm to perform a reaching task. This control method, which uses only two synergies as manipulated variables for driving antagonistic pneumatic artificial muscles to generate desired movements, would be useful to deal with the redundancy problem; thus, suggesting a simple but efficient control for human-like robots to work safely and compliantly with humans. 相似文献
9.
A new Ag/Al2O3 catalyst for removing NOx in lean exhaust gas was developed. Oxidized Ag/Al2O3 catalyst is highly active for reduction of NOx with ethanol and propene, whereas reduced Ag/Al2O3 catalyst is less active for these reactions. Selectivity to N2 is also high on the oxidized Ag/Al2O3 compared to that on the reduced Ag/Al2O3. XRD and SEM studies of these two types of Ag catalysts suggest that oxidation induces an interaction between Ag and the
support, where the particles are grown in large size. In contrast, the metallic Ag particles are finely dispersed by the reduction
process. Although dispersion of Ag particles is decreased by the oxidation process, the catalytic activity is increased. This
suggests that the Ag-alumina sites created in the high temperature oxidizing environment are active in catalytic reduction
of NOx.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
Free primary alcohols in oils and waxes from germs,kernels and other components of nuts,seeds, fruits and cereals 总被引:2,自引:0,他引:2
Kazuko Kawanishi Kumlko Aoki Yohei Hashimoto Akira Matsunobu 《Journal of the American Oil Chemists' Society》1991,68(11):869-872
The composition of free primary alcohols in oils and waxes obtained from the germ, kernel, seed coat, shell and skin (peel)
of various nuts, seeds, fruits and cereals and from the chrysalis of silkworm was examined. These alcohols are usually present
in small amounts, along with large quantities of hydrocarbons, esters and glycerides in oils and waxes. Thus, it is necessary
to remove hydrocarbons, esters and glycerides to analyze the alcohols. We found that preparative reverse-phase thin-layer
chromatography (TLC) was the best way to isolate alcohols from oils and waxes. Gas liquid chromatography (GLC) then detected
hexacosanol, octacosanol and triacontanol in the oils and waxes. Octacosanol usually was the predominant alcohol. Relationships
between the organs from nuts, seeds, fruits and cereals and the contents of octacosanol are suggested. For example, degermed
kernels contained two times more octacosanol than the germ, and the skin coat and shell contained one-half and one-fortieth
the octacosanol of the germ, respectively. 相似文献