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The effect of onset interaural time differences (ITDs) on lateralization and detection was investigated for broadband pulse trains 250 ms long with a binaural fundamental frequency of 250 Hz. Within each train, ITDs of successive binaural pulse pairs alternated between two of three values (0 micros, 500 micros left-leading, and 500 micros right-leading) or were invariant. For the alternating conditions, the experimental manipulation was the choice of which of two ITDs was presented first (i.e., at stimulus onset). Lateralization, which was estimated using a broadband noise pointer with a listener adjustable interaural delay, was determined largely by the onset ITD. However, detection thresholds for the signals in left-leading or diotic continuous broadband noise were not affected by where the signals were lateralized. A quantitative analysis suggested that binaural masked thresholds for the pulse trains were well accounted for by the level and phase of harmonic components at 500 and 750 Hz. Detection thresholds obtained for brief stimuli (two binaural pulse or noise burst pairs) were also independent of which of two ITDs was presented first. The control of lateralization by onset cues appears to be based on mechanisms not essential for binaural detection. 相似文献
104.
Propagation algorithm for computer simulation of stationary paraxial self-focusing laser beam in a medium with saturating
nonlinearity is given in Lie-optic form. Accordingly, a very natural piece-wise continuous Lie transformation that reduces
to a restricted Lorentz group of the beam results. It gives rise to a matrix method for self-focusing beam propagation that
is constructed and implemented. Although the results use plasma nonlinearities of saturable type, and a gaussian initial beam,
these results are applicable for other media like linear optical fibers and to more general situations. 相似文献
105.
Patil Sandip K. Bhise Sagar C. Awale Deepak V. Vadiyar Madagonda M. Patil Suryakant A. Gunjal Dattatray B. Kolekar Govind B. Ghorpade Uma V. Kim Jin H. Kolekar Sanjay S. 《Research on Chemical Intermediates》2018,44(10):6267-6282
Research on Chemical Intermediates - We explored a geminal dicationic ionic liquid (DCIL), 1′-(propane-1,3-diyl)bis(4-aminopyridin-1-ium) dibromide, [C3(Amp)2][Br]2, as a fluorescent probe... 相似文献
106.
Ranjetta Poobathy Uma Rani Sinniah Rathinam Xavier Sreeramanan Subramaniam 《Applied biochemistry and biotechnology》2013,170(5):1066-1079
Dendrobium sonia-28 is an important ornamental orchid in the Malaysian flower industry. However, the genus faces both low germination rates and the risk of producing heterozygous progenies. Cryopreservation is currently the favoured long-term storage method for orchids with propagation problems. Vitrification, a frequently used cryopreservation technique, involves the application of pretreatments and cryoprotectants to protect and recover explants during and after storage in liquid nitrogen. However, cryopreservation may cause osmotic injuries and toxicity to cryopreserved explants from the use of highly concentrated additives, and cellular injuries from thawing, devitrification and ice formation. Reactive oxygen species (ROS), occurring during dehydration and cryopreservation, may also cause membrane damage. Plants possess efficient antioxidant systems such as the superoxide dismutase (SOD) and catalase (CAT) enzymes to scavenge ROS during low temperature stress. In this study, protocorm-like bodies (PLBs) of Dendrobium sonia-28 were assayed for the total protein content, and both SOD and CAT activities, at each stage of a vitrification exercise to observe for deleterious stages in the protocol. The results indicated that cryopreserved PLBs of Dendrobium sonia-28 underwent excessive post-thawing oxidative stress due to decreased levels of the CAT enzyme at the post-thawing recovery stage, which contributed to the poor survival rates of the cryopreserved PLBs. 相似文献
107.
S. Backiyarani S. Uma P. Varatharj M. S. Saraswathi 《Applied biochemistry and biotechnology》2013,169(1):228-238
Expressed sequence tags (ESTs) databases of 11 Musa complementary DNA libraries were retrieved from National Center of Biotechnology Information and used for mining simple sequence repeats (SSRs). Out of 21,056 unique ESTs, SSR regions were found only in 5,158 ESTs. Among these SSR containing ESTs, the occurrence of trinucleotide repeats are the most abundant followed by mono-, di-, tetra-, hexa-, and pentanucleotides. Moreover, this study showed that the rate of class II SSRs (<20 nucleotides) was higher than the class I SSRs (<20 nucleotides), and proportion of class I and II SSRs as abundant for tri-repeats. As a representative sample, primers were synthesized for 24 ESTs, carrying >12 nucleotides of SSR region, and tested among the various genomic group of Musa accessions. The result showed that 88 % of primers were functional primers, and 43 % are showing polymorphism among the Musa accessions. Transferability studies of Musa EST-SSRs among the genera of the order Zingiberales exhibited 100 and 58 % transferability in Musaceae and Zingiberaceae, respectively. The sequence comparison of SSR regions among the different Musa accessions confirmed that polymorphism is mainly due to the variation in repeat length. High percentage of cross-species, cross-genera, and cross-family transferability also suggested that these Musa EST-SSR markers will be a valuable resource for the comparative mapping by developing COS markers, in evolutionary studies and in improvement of the members of Zingiberaceae and Musaceae. 相似文献
108.
Ramesh Bokka Sarma Vanka Uma Maheswara Kumar Katragunta Babu Katragadda Suresh Devi Potturi Sita 《平面色谱法杂志一现代薄层色谱法》2015,28(4):280-286
JPC – Journal of Planar Chromatography – Modern TLC - The isolation and characterization of bioactive compounds from medicinal plants is usually a significant challenge in phytochemical... 相似文献
109.
110.
Alpana Goel Uma V. Sasidharan Nair Archana Yadav 《Central European Journal of Physics》2014,12(9):693-700
The Variable Moment of Inertia (VMI) model is proposed for the assignment of band head spin of super deformed (SD) rotational bands, which in turn is helpful in the spin prediction of SD bands. The moment of inertia and stiffness parameter (C), were calculated by fitting the proposed transition energies. The calculated transition energies are highly dependent on the prescribed spins. The calculated and observed transition energies agree well when an accurate band head spin (I 0) is assigned. The results are in good agreement with other theoretical results reported in literature. In this paper, we have reported the band head spin value 16 rotational band of super deformed Tl isotopes. 相似文献