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991.
Twelve participants were trained to be experts at identifying a set of 'Greebles', novel objects that, like faces, all share a common spatial configuration. Tests comparing expert with novice performance revealed: (1) a surprising mix of generalizability and specificity in expert object recognition processes; and (2) that expertise is a multi-faceted phenomenon, neither adequately described by a single term nor adequately assessed by a single task. Greeble recognition by a simple neural-network model is also evaluated, and the model is found to account surprisingly well for both generalization and individuation using a single set of processes and representations. 相似文献
992.
993.
H Tsuji M Ozeki K Yokoyama S Tachibana H Harunari M Kawakami T Orino T Morimoto A Takeuchi Y Tanaka 《Canadian Metallurgical Quarterly》1989,9(3):297-300
A 59-year-old man, who had had right middle and lower lobectomy for pulmonary tuberculosis, admitted for the treatment of empyema with fistula. Closure of empyema space with free rectus abdominis myocutaneous flap was performed following open window thoracotomy and thoracoplasty. As he previously underwent two major operation, lobectomy by posterolateral approach and gastrectomy for gastric ulcer, free rectus abdominis flap was chosen instead of omental flap or latissimus dorsi myocutaneous flap. Postoperative CT film showed that this flap was filled up in all interstices of the empyema cavity. The pedicle vessels to this flap are large enough to provide long stalks, so microsurgical anastomosis can be accomplished safely. The use of free rectus abdominis myocutaneous flap is one of a useful maneuver for chronic empyema with fistula. 相似文献
994.
Transmission loss increase of optical glass fibre caused by hydrogen diffusion is measured as a function of temperature and partial pressure of hydrogen gas. The activation energy of hydroxyl group formation from the diffused molecular hydrogen was found to be 15.9 kcal/mole. Also the hydroxyl absorption loss increase at 200°C was found to be proportional to the square root of the partial pressure of hydrogen gas. 相似文献
995.
Y Nakanishi-Shindo K Nakayama A Tanaka Y Toda Y Jigami 《Canadian Metallurgical Quarterly》1993,268(35):26338-26345
The periplasmic invertase was purified from Saccharomyces cerevisiae och1::LEU2 disruptant cells (delta och1), which have a defect in elongation of the outer chain attached to the N-linked core oligosaccharides (Nakayama, K., Nagasu, T., Shimma, Y., Kuromatsu, J., and Jigami, Y. (1992) EMBO J. 11, 2511-2519). Structural analysis of the pyridylaminated (PA) neutral oligosaccharides released by hydrazinolysis and N-acetylation confirmed that the och1 mutation causes a complete loss of the alpha-1,6-polymannose outer chain, although the PA oligosaccharides (Man9GlcNAc2-PA and Man10GlcNAc2-PA), in which one or two alpha-1,3-linked mannose(s) attached to the endoplasmic reticulumn (ER)-form core oligosaccharide (Man8GlcNAc2) were also detected. Analysis of the delta och1 mnn1 strain oligosaccharides released from total cell mannoprotein revealed that the delta och1 mnn1 mutant eliminates the alpha-1,3-mannose attached to the core and accumulates predominantly a single ER-form oligosaccharide species (Man8GlcNAc2), suggesting a potential use of this strain as a host cell to produce glycoproteins containing mammalian high mannose type oligosaccharides. The delta och1 mnn1 alg3 mutants accumulated Man5GlcNAc2 and Man8GlcNAc2 in total cell mannoprotein, confirming the lack of outer chain addition to the incomplete corelike oligosaccharide and the leaky phenotype of the alg3 mutation. All the results suggest that the OCH1 gene encodes an alpha-1,6-mannosyltransferase that is functional in the initiation of alpha-1,6-polymannose outer chain addition to the N-linked core oligosaccharide (Man5GlcNAc2 and Man8GlcNAc2) in yeast. 相似文献
996.
997.
Translocation of peptidyl-tRNA from the ribosomal A- to the P-site in the eukaryotic system was extensively investigated using a model system, in which translocation of Phe-tRNA from the A- to the P-site was examined by using the puromycin reaction, and the following results were obtained. 1) The puromycin reaction but not the translocation reaction proceeded at 0 degrees C. Since the latter could be demonstrated at 30 degrees C, it was possible to analyze translocation per se separately from the puromycin reaction. 2) Translocation was completely dependent on the elongation factor-2 (EF-2) and required the presence of GTP, which could be replaced by GMP-P(NH)P provided that the stoichiometric amount of EF-2 with respect to the amount or ribosomes was present. It was further demonstrated that translocation observed in the presence of GTP was catalytic, while that in the presence of GMP-P(NH)P was stoichiometric, indicating that hydrolysis of GTP was required for the catalytic reutilization of EF-2. 3) Translocation promoted by EF-2 in the presence of GMP-P(NH)P could be reversed, which suggests that hydrolysis of GTP is indispensable of the translocation reaction to proceed catalytically and unidirectionally forward. 相似文献
998.
999.
This paper summarizes our research on newly-developed multifilamentary V3Ga and Nb3Sn compound superconductors, including their design, processing, and characteristics such as mechanical and superconducting properties, and coil performance. 相似文献
1000.
We have developed a very-low-loss optical fibre employing silicone resin as the cladding and fused silica as the core. The minimum transmission loss was 3.2 dB/km at 0.84 ?m and the half-pulse width spread was 19 ns/km at 0.80 ?m. 相似文献