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排序方式: 共有249条查询结果,搜索用时 15 毫秒
1.
Drew Michael R.; Yang Cynthia; Ohyama Tatsuya; Balsam Peter D. 《Canadian Metallurgical Quarterly》2004,30(3):163
Three experiments investigated the effects of varying the conditioned stimulus (CS) duration between training and extinction. Ring doves (Streptopelia risoria) were autoshaped on a fixed CS-unconditioned stimulus (US) interval and extinguished with CS presentations that were longer, shorter, or the same as the training duration. During a subsequent test session, the training CS duration was reintroduced. Results suggest that the cessation of responding during an extinction session is controlled by generalization of excitation between the training and extinction CSs and by the number of nonreinforced CS presentations. Transfer of extinction to the training CS is controlled by the similarity between the extinction and training CSs. Extinction learning is temporally specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
We present a local Dissemination of EPIC, a project which has been devised to support health and social primary care by an information system. One key point of the EPIC project was a standardization effort at European level, providing a standardized basis for the management system based on client needs for planning and manpower control. Whilst EPIC has been designed as a general community information system, the main EPIC applications focus is on the care of the elderly. Savona is a middle size Italian town with a high percentage of elderly people and has already had an experience of integration of health and social care within an Italian project. It has therefore been regarded as a suitable site for the dissemination of EPIC. The EPIC application solved some of the information problems which emerged during the validation of the previous Italian project, such as the definition of the requirements; the collection, processing and retrieval of the clinical/social data; the definition of responsibilities and relations of the operators. 相似文献
3.
Although the inhibitory effects of a chronic excess of glucocorticoids (GC) on body growth and GH secretion are well established, the mechanisms involved remain unclear. In this study, we examined the chronic effects of a high dose of dexamethasone (DEX) on spontaneous GH secretion and insulin-like growth factor (IGF)-I in conscious rats. The animals were given daily i.p. injections of DEX (200 microg/day) for either one or four weeks. Body growth assessed by tibia length and serum IGF-I levels was significantly inhibited 1 week after treatment. By contrast, spontaneous GH secretion was not altered 1 week after the treatment. Neither hypothalamic GRH and somtatostain mRNA levels nor GH responses to GRH from single somatotropes were affected 1 week after the treatment. Four weeks after DEX treatment, body growth of the rats was noticeably suppressed. Interestingly, spontaneous GH secretion, hypothalamic GRH mRNA levels and GH responses to GRH were all inhibited 4 weeks after treatment. Pituitary GRH receptor mRNA levels were not altered 1 week after treatment, but increased after 4 weeks. These results indicate that a high dose of DEX initially impairs IGF-I production and subsequently inhibits spontaneous GH secretion in rats. Inhibition of spontaneous GH secretion resulting from chronic GC excess is due, at least in part, to the impairment of hypothalamic GRH synthesis and pituitary GH responsiveness. An increase in the pituitary GRH receptor may be caused by decreased GRH secretion. 相似文献
4.
5.
H. Ohyama K. Takakura H. Matsuoka T. Jono E. Simoen C. Claeys J. Uemura T. Kishikawa 《Journal of Materials Science: Materials in Electronics》2003,14(5-7):437-440
Results are presented of a detailed study of the effects of high-temperature 4-MeV neutron irradiation on the performance degradation of Si pin photodiodes together with the radiation-induced defects, observed by deep level transient spectroscopy (DLTS). It was found that the dark current increases after irradiation, while the photocurrent decreases. After irradiation, two majority electron capture levels with (E
c–0.22 eV) and (E
c–0.40 eV) were induced in the n-Si substrate, while one minority hole capture level with (E
v+0.37 eV) was found. Additionally, the degradation of the device performance and the introduction rate of the lattice defects decreases with increasing irradiation temperature. For a 250 °C irradiation, the reduction of the reverse current is only 20% of the starting value. This result suggests that the creation and recovery of the radiation damage proceeds simultaneously at high temperatures. 相似文献
6.
7.
D Shiokawa H Ohyama T Yamada K Takahashi S Tanuma 《Canadian Metallurgical Quarterly》1994,226(1):23-30
We studied total occlusion of all three coronary arteries. From 1975 to 1992, a total of 4,100 patients underwent coronary arteriography at Show University Hospital. Of these, four patients (0.1%) had complete occlusion of all three coronary arteries and all of them underwent coronary artery bypass grafting (CABG). The mean numbers of coronary risk factors were only 2.3 but history of angina of effort were long-standing such as 4 to 29 years (mean 16.3 yr). All cases had previous episodes of myocardial infarction. Three cases (75%) had aortic aneurysm. One case was also diagnosed as Leriche syndrome besides coexisting aneurysm. Coronary arteriogram showed total occlusion of right coronary artery, left anterior descending artery and left circumflex artery in the segment of 1.6 or 7 and 11 respectively. All cases had intracoronary anastomosis and intercoronary anastomosis. Among 12 occluded coronary arteries of all four cases, 11 were distally visualized with contrast medium via collateral flow but good opacification of the distal coronary trees were not seen. Also proper assessments of cardiac performance including viability of myocardium were not established because all cases were in the state of C.C.S grades IV. But significant clinical recovery were obtained in all cases after CAGB of three or four bypass. We conclude that these results might be a useful suggestion for the treatment of total occlusion of all three coronary arteries. 相似文献
8.
Yasuhiko H. Mori Takehiro Nosoko Atsushi Mikami Tetsuya Ohyama 《Chemical Engineering Communications》1990,92(1):95-102
The shape of interfaces formed by the contact of two liquid phases, immiscible with each other, and a gaseous phase can be predicted on the condition that the tension to work at each interface is known with a sufficient accuracy. In general, interfacial tension data available are not so accurate, however, as to be useful as they are in predicting the shape of interfaces, particularly when the spreading coefficient of either liquid (liquid 1) on the other (liquid 2) has a negative value of a small magnitude. Presented in this note is a simple method to rectify the interfacial tension data, with the aid of a measurement of the radius of a lens of liquid 1 of a known volume placed on the horizontal surface of liquid 2, and thereby make them usable for predicting interfacial geometries. The method is tested by applying it to benzene/water and n-pentane/water systems. 相似文献
9.
The speed-up of supercomputers has increased the complexity of simulations. To analyze such kind of data, we believe that new types of visualization software are needed. Therefore, we have been developing a visualization system called “Fusion Visualization”, and the progresses were reported in the AROB 18th and 19th International Symposiums. We introduced the overall concept at the AROB 18th International Symposium, and then demonstrated a sample of flow visualization in a blood vessel in the AROB 19th International Symposium. To extend our system to enable the handling of larger data, we have implemented the proposed system on a parallelized visualization system; AVS/Express PCE (Parallel Cluster Edition). This paper describes the implementation and the benchmark results. 相似文献
10.
This paper describes a level-of-detail rendering technique for large-scale irregular volume datasets. It is well known that
the memory bandwidth consumed by visibility sorting becomes the limiting factor when carrying out volume rendering of such
datasets. To develop a sorting-free volume rendering technique, we previously proposed a particle-based technique that generates
opaque and emissive particles using a density function constant within an irregular volume cell and projects the particles
onto an image plane with sub-pixels. When the density function changes significantly in an irregular volume cell, the cell
boundary may become prominent, which can cause blocky noise. When the number of the sub-pixels increases, the required frame
buffer tends to be large. To solve this problem, this work proposes a new particle-based volume rendering which generates
particles using metropolis sampling and renders the particles using the ensemble average. To confirm the effectiveness of
this method, we applied our proposed technique to several irregular volume datasets, with the result that the ensemble average
outperforms the sub-pixel average in computational complexity and memory usage. In addition, the ensemble average technique
allowed us to implement a level of detail in the interactive rendering of a 71-million-cell hexahedral volume dataset and
a 26-million-cell quadratic tetrahedral volume dataset. 相似文献