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81.
82.
Goldfish were classically conditioned to a mixture of two pulse trains differing in both repetition rate and the spectral profile of the pulses. Animals were then tested for generalization to single pulse trains having one or the other spectral profile presented at a variety of repetition rates. Generalization functions of repetition rate were qualitatively similar to those obtained following conditioning to either of the pulse trains alone. Thus, the spectral profile of each pulse type was appropriately associated with the repetition rate at which that pulse type was presented during conditioning. These results indicate that the two concurrent pulse trains making up the conditioning stimuli were analyzed independently, forming two auditory streams. When either of the two pulse trains were presented with a 500 ms onset asynchrony, stream segregation was enhanced. These and other results suggest that many fundamental features of the human sense of hearing are widely shared among vertebrate animals, and may have developed first among fishes.  相似文献   
83.
A significant weight loss of copper plate was observed after copper-water vapor interaction near critical point. This leads to the acceleration of the ceramic layer formation on SUS surface during granite-water vapor interaction in the presence of copper. In this paper, we have determined the chemical state of copper at which the mass transfer takes place through reaction with H2 and O2+N2 gas mixture at the different O2 amount. Obtained results indicate that the weight loss of copper plate occurs at Cu2O (+1) state due to a complex processes. The morphology of copper species on the surface of mesh and granite suggests that the Cu2O was dissolved in water vapor and recrystallized on the surface of mesh and granite. Copper species were characterized by X-ray diffraction(XRD), scanning electron microscopy (SEM) equipped with an energy dispersive X-ray (EDX).  相似文献   
84.
Fire retardant GRP sheets based on tetrachlorophthalic acid-modified polyester resin subjected to either artificial or natural weathering undergo two types of surface deterioration (breakdown at the glass-resin interface resulting in fibre prominence and surface microcracking) 2.5 to 3 times faster than conventional sheets. Exposure to humidity-temperature cycles produces fibre prominence at comparable rates for both types of GRP sheets, but does not induce formation of surface microcracking. The surface of the fire retardant sheets protected with weather-resistant poly (vinyl fluoride) (PVF) film does not undergo breakdown when subjected to accelerated or natural exposures.  相似文献   
85.
We experienced two siblings of type 3 GM1 gangliosidosis. A 33-year-old woman developed dysarthria, dysbasia and bradykinesia at around the age of 30. Her 28-year-old brother showed locomotor retardation and skeletal deformity in infancy. He lost the ability to stand walk at childhood, and developed progressive dystonia. The major neurologic manifestations were parkinsonian symptoms in the elder sister, and progressive dystonia in her brother. Both had markedly reduced beta-galactosidase activity in peripheral blood lymphocyte and were diagnosed as having type 3 GM1 gangliosidosis. Gene analysis revealed that these patients were homozygotes of the adult type mutant gene. The two siblings are unique in that the clinical manifestations and the age of onset of symptoms differed markedly between them despite the same mutant gene in both cases.  相似文献   
86.
87.
With a view to clarifying the characteristics in alumoxanes as an effective Lewis acid cocatalyst in homogeneous olefin polymerization, ab initio quantum chemical calculations were carried out for model fragment structures of the compound. The relative strength of Lewis acidity was compared for different aluminum sites and the energetics in the ligand exchange process with group IV metallocene complex were discussed.  相似文献   
88.
89.
Room-temperature ring oscillation at 19.6 ps/gate has been accomplished with SAINT FETs using bulk GaAs and implantation. These results have been obtained along with extrinsic resistance reduction and capacitance reduction by taking full advantage of the n+-gate spacing controllability.  相似文献   
90.
We examined gap junctional intercellular communication (GJIC) of primary human mesothelial cells and cell lines of asbestos-associated human pleural mesotheliomas, and the effect of asbestos and other mineral fibres on these cells. In homologous cultures, the GJIC capacity of six out of seven tumour cell lines was markedly less than for primary mesothelial cells. This defect in GJIC appeared not to be at the expression level of mRNA and protein of the gene encoding the 43 kDa gap junction protein. In heterologous cocultures of tumour cells and primary mesothelial cells, however, 80-90% of the tumour cell/normal cell contacts were functional. Exposure of primary mesothelial cells to TPA, a phorbol ester tumour promoter, resulted in marked inhibition of GJIC, being an action common to numerous tumour promoters. Such an effect though was not observed with the carcinogenic mesothelioma-inducing mineral fibres chrysotile and amosite, neither with glass wool. These results suggest that a permanent defect in GJIC capacity is a common feature of human mesothelioma cells, but how mineral fibres are involved in the process of mesotheliomagenesis is still unclear.  相似文献   
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