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81.
Sakari Leino Patrick JC May Paavo Alku Lassi A Liikkanen Hannu Tiitinen 《BMC neuroscience》2007,8(1):78
Background
In the field of auditory neuroscience, much research has focused on the neural processes underlying human sound localization. A recent magnetoencephalography (MEG) study investigated localization-related brain activity by measuring the N1m event-related response originating in the auditory cortex. It was found that the dynamic range of the right-hemispheric N1m response, defined as the mean difference in response magnitude between contralateral and ipsilateral stimulation, reflects cortical activity related to the discrimination of horizontal sound direction. Interestingly, the results also suggested that the presence of realistic spectral information within horizontally located spatial sounds resulted in a larger right-hemispheric N1m dynamic range. Spectral cues being predominant at high frequencies, the present study further investigated the issue by removing frequencies from the spatial stimuli with low-pass filtering. This resulted in a stepwise elimination of direction-specific spectral information. Interaural time and level differences were kept constant. The original, unfiltered stimuli were broadband noise signals presented from five frontal horizontal directions and binaurally recorded for eight human subjects with miniature microphones placed in each subject's ear canals. Stimuli were presented to the subjects during MEG registration and in a behavioral listening experiment. 相似文献82.
Trong Phu Do Pascal Ziegler 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(4):359-388
Gear drives are key components for all kinds of machines as well as of industrial equipment. Therein, beveloid gears and cycloid gears are increasingly used in industry. Gaining a more comprehensive understanding of those types of gears is essential. However, the measurement of the dynamic response of these gears is not an option due to the high cost of the required experiments. Along with the development of computer technology, several numerical tools and methods to study gears with standard and non-standard flank profiles have been introduced. Various works related to standard gears or beveloid and cycloid gears have been published. In this study, a contemporary review about the modelling and contact simulation of beveloid and cycloid gear drives will be given. Some studies will also be introduced to present an efficient approach to simulate contact forces and contact characteristics of gear wheels with standard and non-standard tooth profiles considering deformations too. 相似文献
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85.
George Eng Pamela K. McKinney-Forbes Kristy L. Richie Van V. Nguyen
Leopold May
《Journal of organometallic chemistry》1986,310(3):285-291To obtain more structural information on complexes formed between alkyltin halides and bidentate ligands, the solid-state IR and Mössbauer spectra of the 1,2-ethanediamine and 1,4-butanediamine complexes of trimethyltin halides and dimethyltin dihalides were examined. The structures of the trimethyltin halide complexes were found to be trigonal bipyramidal with coplnar methyl groups. The dimethyltin dihalide complexes were octahedral with the methyl groups in the cis-positions and the halides trans to each other. However, there were no differences in the structures of the chloro and bromo complexes of either type. 相似文献
86.
Colloid and Polymer Science - Die gegenseitige Flockung von vier verschiedenen Eisenoxydsolen, deren Konstitution nach Wintgen-Biltz bestimmt worden war, mit acht verschiedenen negativen Solen... 相似文献
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88.
W. Simarew S. G. Menefee O. R. Overman A. Gorbatschewa H. Chr Jorgensen I. V. Hunt A. Konoplew H. Fincke C. Ehrlich R. Trommsdorff M. Asdrubali S. Hadwen R. Gwatkin F. K. Neave H. D. Kay W. R. Graham R. Aschaffenburg A. Jepsen P. Madelung Ch. Paley H. Kreker A. M. Williams May Davies S. B. Thomas G. M. Phillips W. M. Ashton G. D. Simons J. Davies B. F. Thomas L. Little H. A. Sirks G. Sjöström P. Jaulmes L. Poujol und J. A. B. Smith 《Fresenius' Journal of Analytical Chemistry》1943,126(7):282-286
Ohne Zusammenfassung 相似文献
89.
May Lee Low Cheang Wei Chan Pei Ying Ng Ing Hong Ooi Mohd Jamil Maah Soi Moi Chye 《Journal of Coordination Chemistry》2017,70(2):223-241
Three ternary copper(II) complexes, [Cu(phen)(L-phe)Cl]·2H2O, [Cu(phen)(L-leu)Cl]·4½H2O, and [Cu(phen)(L-tyr)Cl]·3H2O, and four binary copper(II) complexes, [Cu(phen)Cl2], Cu(L-phe)2·½H2O, Cu(L-leu)2·½H2O, and Cu(L-tyr)2·H2O (where phen = 110-phenanthroline, L-phe = L-phenylalanine, L-tyr = L-tyrosine, L-leu = L-leucine and Cl- = chloride), were synthesized and characterized by elemental analysis, spectroscopic techniques (FTIR, UV–visible, fluorescence spectroscopy), magnetic susceptibility, molar conductivity, and lipophilicity measurement. X-ray diffraction determination of a single crystal of [Cu(phen)(L-tyr)Cl] showed two independent molecules in the asymmetric unit, each with the same distorted square pyramidal geometry about copper(II). p-Nitrosodimethylaniline assay revealed that the three ternary complexes were better inducers of reactive oxygen species over time than binary complexes, CuCl2, and free ligands. All the copper(II) complexes in this series inhibited the three proteolytic activities in the order Trypsin-like > Caspase-like > Chymotrypsin-like. In terms of anticancer properties, the copper(II)-phen complexes had GI50 values of less than 4 μM against MCF-7, HepG2, CNE1 and A549 cancer cell lines, more potent than cisplatin. 相似文献
90.
Phu H. Dang Tho H. Le Phuong K.T. Phan Phuong T.T. Le Mai T.T. Nguyen Nhan T. Nguyen 《Tetrahedron letters》2017,58(16):1553-1557
Two acridones, paratrimerins C (1) and D (2), and two coumarins, paratrimerins E (3) and F (4), were isolated from the CHCl3 and EtOAc extracts of Paramignya trimera (Rutaceae), together with twelve known compounds (5–16). Their structures were elucidated on the basis of spectroscopic data. All isolated compounds possessed significant α-glucosidase inhibitory activity in a concentration-dependent manner, and showed more potent inhibitory activity, with IC50 values ranging from 14.6 to 112.2 μM, than the positive control acarbose (IC50, 214.5 μM). The biosynthesis of the isolated coumarins and acridones was proposed. 相似文献