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21.
Epitaxial multilayer thin films of infinite-layer (Sr, Ca)CuO2 and perovskite (Sr, Ca)RuO3 have been prepared on (100) SrTiO3 substrates by multitarget rf magnetron sputtering. X-ray diffraction analyses revealed that the multilayer structure of (Sr, Ca)CuO3/(Sr, Ca)RuO3 was successfully fabricated with a minimum layer thickness of 20 Å. Transmission electron microscopy measurements of the multilayers indicated that there was no dislocation which normally exists in single-layer films with an infinite-layer structure. Resistivities of multilayer films at room temperature ranged from 1 to 10 m cm and showed semiconductor-like dependence against the temperature.  相似文献   
22.
The co–enzyme specificity of 3–isopropylmalate dehydrogenasefrom an extreme thermophile, Thermus thermophilus HB8, was changedfrom NAD to NADP by site–directed mutagenesis Based onsequence comparison of 3–isopropylmalate dehydrogenasesfrom various organisms with NAD– and NADP–dependentisocitrate dehydrogenases, Ser226, Ser253 and De279 of 3–isopropylmalatedehydrogenase were suggested as determining the co–enzymespecificity. These residues were replaced with the correspondingresidues of NADP–dependent isocitrate dehydrogenases;Arg, Gly and Tyr respectively. The single–mutated enzymes,S226R and I279Y, enhanced the activities towards NADP 10–and 3–fold respectively, whereas S253G reduced the activity.Among the multiple–mutated enzymes, the double–mutatedS226R/I279Y increased the catalytic efficiency against NADP( fold) and shifted the specificity for NAD towards NADP mostsignificantly ( 173–fold).  相似文献   
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24.
BACKGROUND: This article presents results of the acute treatment phase of a 2-site study comparing cognitive behavioral group therapy (CBGT) and treatment with the monoamine oxidase inhibitor phenelzine sulfate for social phobia. METHODS: One hundred thirty-three patients from 2 sites received 12 weeks of CBGT, phenelzine therapy, pill placebo administration, or educational-supportive group therapy (an attention-placebo treatment of equal credibility to CBGT). The "allegiance effect," ie, the tendency for treatments to seem most efficacious in settings of similar theoretical orientation and less efficacious in theoretically divergent settings, was also examined by comparing responses to the treatment conditions at both sites: 1 known for pharmacological treatment of anxiety disorders and the other for cognitive behavioral treatment. RESULTs: After 12 weeks, phenelzine therapy and CBGT led to superior response rates and greater change on dimensional measures than did either control condition. However, response to phenelzine therapy was more evident after 6 weeks, and phenelzine therapy was also superior to CBGT after 12 weeks on some measures. There were few differences between sites, suggesting that these treatments can be efficacious at facilities with differing theoretical allegiances. CONCLUSIONS: After 12 weeks, both phenelzine therapy and CBGT were associated with marked positive response. Although phenelzine therapy was superior to CBGT on some measures, both were more efficacious than the control conditions. More extended cognitive behavioral treatment and the combination of modalities may enhance treatment effect.  相似文献   
25.
This article presents the micro-electro-mechanical systems (MEMS) microrobot which demonstrates locomotion controlled by hardware neural networks (HNN). The size of the microrobot fabricated by the MEMS technology is 4 × 4 × 3.5 mm. The frame of the robot is made of silicon wafer, and it is equipped with a rotary-type actuator, a link mechanism, and six legs. The rotary-type actuator generates rotational movement by applying an electrical current to artificial muscle wires. The locomotion of the microrobot is obtained by the rotation of the rotary-type actuator. As in a living organism, the HNN realized robot control without using any software programs, A/D converters, or additional driving circuits. A central pattern generator (CPG) model was implemented as an HNN system to emulate the locomotion pattern. The MEMS microrobot emulated the locomotion method and the neural networks of an insect with the rotary-type actuator, the link mechanism, and the HNN. The microrobot performed forward and backward locomotion, and also changed direction by inputting an external trigger pulse. The locomotion speed was 0.325 mm/s and the step width was 1.3 mm.  相似文献   
26.
Comparisons have been made between computational results obtained with the BNL code system and experimental data measured by Vasfl'kov et al. for 56 x 56 x 64 cm natural and depleted uranium blocks surrounded by lead walls and primary proton energies of 400 and 660 MeV. The energetic protons from a linear accelerator are used to produce an intensive neutron source inthe uraniumblocko The computercode system prepared at BNL to perform nuclear design analyses of linear accelerator reactors consists of six main programs: NMTC for spallation-evaporation processes above 15 MeV, HIST3D for the analysis of collision event records obtained by NMTC to get P3 neutron source distribution, DLC-2 to compile 100 energy group cross sections, TAPEMAKER for format conversion, ANISN to collapse 100 group cross sections to fewer group P3 cross section sets, and the principal code TWOTRAN-II which performs neutron reaction and transport calculations in the energy range below 15 MeV. Our computational method gives conservative total neutron yields, i.e., underestimates of about 16.8–29.8% in comparison with measured values depending on proton energy. Radiative capture238U(n,) density distributions have been compared between the calculation and experiment. The calculated distribution has the higher peak in the central part of the target system and the steeper gradient both in the r and z directions.Brookhaven National Laboratory, Upton, New York 11973. Published in Atomnaya Énergiya, Vol. 47, No. 2, pp. 83–91, August, 1979.  相似文献   
27.
In recent years, the techniques improving sliding performances have progressed by using coated films possessing superior tribological properties, to reduce the failures of the mechanical elements. Those techniques are often used under severe conditions such as elastohydrodynamic lubrication (EHL). In this paper, numerical three-dimensional analysis of the maximum shear stress applied into the coated film and substrate under a single EHL operating condition was performed with a range of coated film thickness and elastic properties. The strength of coated film as one of those techniques was evaluated numerically, resulting in an optimum design of coated film. As a result, coated films with a larger value of thickness and a smaller modulus of elasticity than that of substrate are preferable.  相似文献   
28.
Incremental Focus of Attention for Robust Vision-Based Tracking   总被引:3,自引:0,他引:3  
We present the Incremental Focus of Attention (IFA) architecture for robust, adaptive, real-time motion tracking. IFA systems combine several visual search and vision-based tracking algorithms into a layered hierarchy. The architecture controls the transitions between layers and executes algorithms appropriate to the visual environment at hand: When conditions are good, tracking is accurate and precise; as conditions deteriorate, more robust, yet less accurate algorithms take over; when tracking is lost altogether, layers cooperate to perform a rapid search for the target and continue tracking.Implemented IFA systems are extremely robust to most common types of temporary visual disturbances. They resist minor visual perturbances and recover quickly after full occlusions, illumination changes, major distractions, and target disappearances. Analysis of the algorithm's recovery times are supported by simulation results and experiments on real data. In particular, examples show that recovery times after lost tracking depend primarily on the number of objects visually similar to the target in the field of view.  相似文献   
29.
Galactose and N-acetyl-D-galactosamine-inhibitable lectin of Entamoeba histolytica have roles in the pathogenicity of intestinal amoebiasis. Igl1, the intermediate subunit lectin-1 of E. histolytica, has been shown to have both hemolytic and cytotoxic activities that reside in the C-terminus of the protein. To identify the amino acid regions responsible for these activities, recombinant proteins were prepared and used in hemolytic and cytotoxic assays. The results revealed that Igl1 has multiple domains with hemolytic and cytotoxic activities and that amino acids 787-846, 968-1028 and 1029-1088 are involved in these activities. The hemolytic activities of the fragments were partly inhibited by mannose, galactose and N-acetylgalactosamine, and glucose showed lower or negligible inhibitory effects for the activities. This is the first report of a protozoan protein with hemolytic and cytotoxic activities in multiple domains.  相似文献   
30.
KIT is a type-III receptor tyrosine kinase that contributes to cell signaling in various cells. Since KIT is activated by overexpression or mutation and plays an important role in the development of some cancers, such as gastrointestinal stromal tumors and mast cell disease, molecular therapies targeting KIT mutations are being developed. In acute myeloid leukemia (AML), genome profiling via next-generation sequencing has shown that several genes that are mutated in patients with AML impact patients’ prognosis. Moreover, it was suggested that precision-medicine-based treatment using genomic data will improve treatment outcomes for AML patients. This paper presents (1) previous studies regarding the role of KIT mutations in AML, (2) the data in AML with KIT mutations from the HM-SCREEN-Japan-01 study, a genome profiling study for patients newly diagnosed with AML who are unsuitable for the standard first-line treatment (unfit) or have relapsed/refractory AML, and (3) new therapies targeting KIT mutations, such as tyrosine kinase inhibitors and heat shock protein 90 inhibitors. In this era when genome profiling via next-generation sequencing is becoming more common, KIT mutations are attractive novel molecular targets in AML.  相似文献   
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