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571.
572.
Le Prell CG Yagi M Kawamoto K Beyer LA Atkin G Raphael Y Dolan DF Bledsoe SC Moody DB 《The Journal of the Acoustical Society of America》2004,116(2):1044-1056
Brief cochlear excitotoxicity produces temporary neural swelling and transient deficits in auditory sensitivity; however, the consequences of long-lasting excitotoxic insult have not been tested. Chronic intra-cochlear infusion of the glutamate agonist AMPA (a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) resulted in functional deficits in the sound-evoked auditory brainstem response, as well as in behavioral measures of hearing. The electrophysiological deficits were similar to those observed following acute infusion of AMPA into the cochlea; however, the concentration-response curve was significantly shifted as a consequence of the slower infusion rate used with chronic cochlear administration. As observed following acute excitotoxic insult, complete functional recovery was evident within 7 days of discontinuing the AMPA infusion. Distortion product otoacoustic emissions were not affected by chronic AMPA infusion, suggesting that trauma to outer hair cells did not contribute to AMPA-induced deficits in acoustic sensitivity. Results from the current experiment address the permanence of deficits induced by chronic (14 day) excitotoxic insult as well as deficits in psychophysical detection of longer duration acoustic signals. 相似文献
573.
Sohma Y Sasaki M Hayashi Y Kimura T Kiso Y 《Chemical communications (Cambridge, England)》2004,(1):124-125
A novel and efficient method for the synthesis of difficult sequence-containing peptides has been developed based on the synthesis of O-acyl isopeptides followed by an O-N intramolecular acyl migration reaction, resulting in a remarkable improvement of the yields. 相似文献
574.
Mil'nikov GV Yagi K Taketsugu T Nakamura H Hirao K 《The Journal of chemical physics》2004,120(11):5036-5045
A practical and accurate semiclassical method for calculating the tunneling splitting of the ground state in polyatomic molecules is presented based on a recent version of the instanton theory [J. Chem. Phys. 115, 6881 (2001)]. The method uses ab initio quantum chemical data for the potential energy surface without any concomitant extrapolation and requires only a small number of ab initio data points to get convergence even for large molecules. This enables one to use an advanced level of electronic structure theory and achieve a high accuracy of the result. The method is applied to the 9-atomic malonaldehyde molecule by making use of the potential energy surface at the level of CCSD(T) with the hybrid basis set of aug-cc-pVTZ (for oxygen atoms and the transferred hydrogen atom) and cc-pVTZ (for other atoms). 相似文献
575.
576.
Jong-Ho Park Jung-Hwan Kim Sung-Ho Suh Jang-Kyoo Shin Minho Lee Pyung Choi Tetsuya Yagi 《Optical Review》2005,12(1):15-19
We have designed and fabricated a complementary metal-oxide-semiconductor (CMOS) vision chip by modeling cells of the human retina as hardware that are involved in edge and motion detection. There are several fluctuation factors which affect the characteristics of metal-oxide-semiconductor field effect transistors (MOSFETs) through the CMOS fabrication process and this effect appears as the output offset of the vision chip, which is composed of pixel arrays and readout circuits. The vision chip which detects edge and motion information from an input image is used for the input stage of other systems. Therefore, the output offset of the vision chip determines the efficiency of the entire system. In order to eliminate the offset at the output stage, we designed a vision chip utilizing the correlated double sampling (CDS) technique. The chip has been fabricated using a 0.6 m standard CMOS process. With reliable output characteristics, this chip can be used at the input stage for various applications. © 2005 The Optical Society of Japan 相似文献
577.
The specific heat of typical relaxors, Pb(Mg(1/3)Nb(2/3))O3 (PMN) and Pb(Mg(1/3)Ta(2/3))O3 (PMT), was measured by adiabatic and relaxation methods between 2 and 420 K. A broad anomaly was found in the specific heat curve over the wide temperature range between 150 and 500 K for PMN, and between 50 and 400 K for PMT, which provides evidence for the formation of ferroelectric nanoregions (FNR) in the paraelectric matrix. The entropy of the anomaly was estimated as 3.3 J K(-1) mol(-1) and 2.9 J K(-1) mol(-1) for PMN and PMT, respectively, which implies an order-disorder-type mechanism for the formation of FNR. 相似文献
578.
579.
580.
K. Yagi Y. Aoki C. Rangacharyulu K. Matoba M. Hyakutake J. Nidome 《Physics letters. [Part B]》1973,44(5):447-448
Differential cross sections of (p, t) reactions exciting the 2+1 states in Te (A = 128 ? 120), Sn (116 and 114) and Cd (114 and 112) have been measured at Ep = 52 MeV. The observed differences of the angular distributions are interpreted by taking into account the two-step processes through inelastic scattering channels. 相似文献