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41.
A 5 in. diameter Si(Li)/Pb sampling calorimeter with a depth of 28 radiation lengths (30 unit cells × 0.93 radiation lengths) has been constructed. The energy and angular resolutions of the calorimeter have been investigated using CERN SPS positron beams with energies of 10 to 147.8 GeV. The calorimeter shows good linearity over this energy region and the energy resolution is expressed well by σE (rms)/E = (16.9 ± 0.9)%/ √E[GeV], where E represents the incident beam energy. The angular resolution of the calorimeter for a single event is 0.3° (rms) at 80 GeV/c. The agreement between these results and Monte Carlo simulations is good.

We are showing a new design of the Si(Li)/Pb sampling calorimeter telescope (SSCT) with an angular resolution (point source localization capability) of about 0.04° (rms) for bright galactic gamma-ray sources. We believe that this telescope is a suitable detector for future observations of cosmic gamma rays in the GeV region, especially when used to search for point sources.  相似文献   

42.
An increasing concern in contemporary psychology in Japan is the study of observational learning and imitation in the social learning, personality, and clinical fields. The literature in these fields from 1964 to 1975 is reviewed, including learning-by-observing vs learning-by-performing, observer learning, the process of observational learning, mediational processes, effects of motivation on observational learning, effects of various reinforcement factors underlying modeling, the relationship between model and observer, observational learning studies unique to Japan, application of modeling to clinical fields, and self-reinforcement. (1? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
Sera from 23 patients with idiopathic thrombocytopenic purpura (ITP), 14 patients with aplastic anemia with severe thrombocytopenia and healthy control subjects were tested for the presence of fibrinogen/fibrin degradation products (FDP), using the tanned red cell hemagglutination inhibition immunoaassay. The concentrations of circulating FDP of ITP patients (mean 12.01 mug/ml) were significantly higher than those of the patients with aplastic anemia (mean 4.01 mug/ml, p less than 0.05) or normal controls (mean 3.10 mug/ml, p less than 0.001). The patients with untreated ITP with very low platelet counts had higher levels of FDP than those of the treated group (p less than 0.01). Serum FDP and a battery of other coagulation-fibrinolysis tests were serially carried out over a period of 10 weeks in two patients with ITP. The initially high FDP promptly decreased as circulating platelets increased in response to steroid in both patients, while plasma fibrinogen, euglobulin lysis time, prothrombin time and partial thromboplastin time remained essentially normal during the course of observation. The exact source of the increased serum FDP in ITP was not established, but a few possible mechanisms responsible for this abnormality were discussed.  相似文献   
44.
Pigeons and humans were trained to discriminate between sets of artificial stimuli defined by a 2-out-of-3 polymorphous concept. Stimuli containing any 2 of 3 positive or negative features were used for training. In Exp 1, pigeons showed complete transfer to stimuli with all 3 positive or negative features and even to stimuli that had 1 of the 3 features replaced with a novel feature. In contrast, humans failed to show transfer to those stimuli. By using a selective reversal procedure for pigeons, Exp 2 revealed that functional equivalence was not formed among either the stimuli or the features. Exp 3 examined how pigeons integrate information from several distinct features to determine the response to any given stimulus. An additive rule and a combination rule were suggested to account for category discrimination by pigeons. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
45.
Ag-sheathed Bi-2223 superconducting oxide conductors with a critical current density of 66,000 A/cm2 at 77 K and coils that have generated magnetic fields of approximately 1.5 Tesla at 4.2 K have been successfully developed. The conductors consist of piled-up bundles of four to six sheets of element tapes with transport currents of approximately 200 Amps. The core size limit (CSL) prevented the production of single conductors that had the capacity to transport a current as high as 200 Amps at 4.2 K. Until now, it was difficult to develop a conductor having both high critical current density and the capability of transporting a large amount of current simultaneously. The role of CSL in large scale applications of high temperature superconducting oxides is discussed.  相似文献   
46.
A nest set is the language generated by a context-free grammar whose rules are A → aBa?C or A? (where a, ā are paired terminal symbols, and A, B, C are nonterminal symbols). They can be seen as the one-dimensional expressions of the recognizable sets of binary trees. We study their closure properties under relativized operations with respect to the Dyck set, which is the maximum set in the class. The operations considered are relativized versions of AFL operations, quotient, direct product, shuffle product, and some others. As an application we prove various closure properties of generalized parenthesis languages.  相似文献   
47.
Serial-probe-recognition (SPR) performance by 2 monkeys deteriorated over several months of training. Three hundred and twenty different items were presented without repetition within a session (trial unique) but were repeated between sessions. The cause of the deterioration was identified as proactive interference (PI) due to repetitive use of items from day to day. Introduction of novel stimuli across days improved performance from 63% to 82% correct (Experiment 1). Tests with only probe items and no list items (Experiment 2) revealed that the monkeys were using a familiar/novel response strategy in combination with a relational strategy (relating the probe item to the list items) to further improve their SPR performance. Intermixing familiar baseline trials and novel transfer trials within a session (Experiment 3) encouraged the subjects to use a relational strategy, and it improved performance on baseline trials as well as on transfer trials. Possible qualitative similarity between the relational strategy and the familiar/novel response strategy is discussed along with theoretical implications of these findings for experiments which have used small number of repeating stimuli within a session. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
48.
The significant increase of output energy of a UV-preionized KrF laser has been obtained by a change of electrode separation. This fact is explained by the measured impedance and deposit energy in a discharge. The efficient amplification has been performed by using a exactly synchronized amplification system. The maximum output energy was 0.75 J/pulse with a pulsewidth of 40 ns and a total efficiency of 0.8 percent. The saturation intensity and small-signal gain coefficient for KrF laser have been measured. The saturation intensity was 1.7 MW/cm2and the small-signal gain coefficient reached 4.7 percent/cm at a charging voltage of 35 kV.  相似文献   
49.
A 68-year-old woman with mitral valve regurgitation due to ruptured chordae tendineae of posterior leaflet underwent mitral valve repair by replacement of chordae tendineae with EPTFE sutures and Carpentier-Edwards ring techniques. Preoperative study showed massive mitral regurgitation and moderate tricuspid regurgitation with CTR 54% of chest X-ray. The postoperative course was not eventful. Postoperative study showed trivial mitral and trivial tricuspid regurgitation. Postoperative CTR was 45%. Mitral valve repair by these techniques could be modified and applicable to mitral valve regurgitation due to ruptured chordae tendineae of posterior leaflet. There was no complication during follow-up period of 8 months.  相似文献   
50.
In order to examine the production mechanism of the midsystolic click in cases of a midsystolic click and a late systolic murmur, the relationship between the click and the motion of the mitral apparatus was studied by means of ultrasono-cardiotomography and the simultaneous recording of phonocardiograms and ultrasono-cardiograms (UCGs). It was found that the systolic click occurred in exact coincidence with the time at which the hump of the echo of the unusual early systolic anterior motion (early SAM) took its backmost position. This coincidence was found when the click was shifted either by postural changes or inhalation of amyl nitrite. The present ultrasono-cardiotomographic study demonstrated that the echo source of the early SAM could be attributed to the protrusion into the left ventricular outflow tract of the slackened elongated chordae tendineae in systole. The anterior leaflet moved suddenly to the position of maximal prolapse when the slackened chordae tendineae were stretched taut in midsystole. In other words, the midsystolic click occurred when the anterior leaflet prolapsed and the tension exerted on the chordae tendineae was at its maximum.  相似文献   
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