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101.
102.
Yu. S. Ravkin S. M. Tsybulin S. G. Livanov K. V. Toropov V. N. Kuranova V. P. Starikov S. V. Chesnokova 《Contemporary Problems of Ecology》2008,1(5):568-573
For the entire territory of West Siberia, including its plain and mountainous parts, two maps were constructed for populations of amphibians together with reptiles, and of birds. Communities of these classes of vertebrates differ from one another in their spatial differentiation. The differences are demonstrated for the plain and mountainous territories considered jointly and separately. 相似文献
103.
Alan C. L. Yu 《PloS one》2010,5(8)
Variation is a ubiquitous feature of speech. Listeners must take into account context-induced variation to recover the interlocutor''s intended message. When listeners fail to normalize for context-induced variation properly, deviant percepts become seeds for new perceptual and production norms. In question is how deviant percepts accumulate in a systematic fashion to give rise to sound change (i.e., new pronunciation norms) within a given speech community. The present study investigated subjects'' classification of /s/ and // before /a/ or /u/ spoken by a male or a female voice. Building on modern cognitive theories of autism-spectrum condition, which see variation in autism-spectrum condition in terms of individual differences in cognitive processing style, we established a significant correlation between individuals'' normalization for phonetic context (i.e., whether the following vowel is /a/ or /u/) and talker voice variation (i.e., whether the talker is male or female) in speech and their “autistic” traits, as measured by the Autism Spectrum Quotient (AQ). In particular, our mixed-effect logistic regression models show that women with low AQ (i.e., the least “autistic”) do not normalize for phonetic coarticulation as much as men and high AQ women. This study provides first direct evidence that variability in human''s ability to compensate for context-induced variations in speech perceptually is governed by the individual''s sex and cognitive processing style. These findings lend support to the hypothesis that the systematic infusion of new linguistic variants (i.e., the deviant percepts) originate from a sub-segment of the speech community that consistently under-compensates for contextual variation in speech. 相似文献
104.
The possibility of the use of small amounts of chitosan for defatting and clarification of protein solutions prepared by enzymatic hydrolysis was tested. The following treatment conditions were shown to be optimal: a chitosan concentration range, from 1.0 to 1.5 gram per kilogram raw weight; pH of the precipitation medium from 8.0 to 8.5; and duration of the incubation of the protein hydrolysate solution with chitosan, less than 1 h. The hydrolysate defatting grade was found to depend on the degree of chitosan deacetylation. A possible mechanism of the chitosan-induced effects was suggested. The use of chitosan allows the mass fraction of enzyme protein hydrolysates to be reduced fourfold to fivefold. 相似文献
105.
Aiyi Liu James F. Troendle Kai F. Yu Vivian W. Yuan 《Biometrical journal. Biometrische Zeitschrift》2004,46(6):760-768
We consider estimation after a group sequential test. An estimator that is unbiased or has small bias may have substantial conditional bias (Troendle and Yu, 1999, Coburger and Wassmer, 2001). In this paper we derive the conditional maximum likelihood estimators of both the primary parameter and a secondary parameter, and investigate their properties within a conditional inference framework. The method applies to both the usual and adaptive group sequential test designs. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
106.
Different approaches to interpretation of ontogenesis are compared. The importance is emphasized of Ber’s theory of developmental patterns and the law of embryonic similarity. The significance of evolutionary rationalization of morphogenetic mechanisms is discussed (V.N. Beklemishev, V.A. Dogel’ and O.M. Ivanova-Kazas). There are two main pathways of rationalization of morphogenetic mechanisms: by means of epithelial morphogenesis and at the expense of oligocellular primordia (V.N. Beklemishev). When the developmental plans of the taxonomical types are determined, it is important to take into consideration the diversity of morphogenetic mechanisms within a given group in order to reveal morphological spectrums of morphogenetic mechanisms. A comparison of morphogenetic spectrums in different groups provides a wide evolutionary picture and helps us to reconstruct the phylogeny. Influence of morphogenetic mechanisms on the structure of definitive forms is demonstrated: construction technologies determine types of organs, anatomical and histological systems, and even symmetrical features of organisms and their complex parts. 相似文献
107.
JERZY DZIK REY Yu. IVANTSOV YURIY V. DEULIN 《Zoological Journal of the Linnean Society》2004,142(1):83-90
A mass occurrence of schooling, weakly sclerotized eocaridid shrimps in the Early Devonian pelagic environment of northern Russia suggests that the body-plan of the Eumalacostraca originated as an adaptation to swimming in the open sea. They probably replaced their ecological analogues, the archaeostracan phyllocarids Caryocaris , as a consequence of the rebuilding of the global marine environment during the later Ordovician. This may explain the rarity of the eumalacostracans in the Devonian and the difficulty with documenting their links with the archaeostracans. The new eocaridid shows similarities to the Carboniferous Anthracophausia in the general appearance and weak sclerotization of the carapace and appendages, but lacks its derived characters. The morphology of the pleural lobes, which have minute spines, is the only identified distinguishing character of the proposed new genus and species Archangeliphausia spinosa gen. et sp. nov. Its carapace was probably firmly connected dorsally with the thoracic segments. The only associated fossils of the assemblage represent a bizarre archaeostracan Pechoracaris aculicauda gen. et sp. nov., with a weakly sclerotized carapace lacking any hinge or rostral plates but with reduced furca, an extremely long caudal spine and pleopods transformed into spines. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 142 , 83–90. 相似文献
108.
It was shown that the rabbit sensorimotor cortex received afferent fibers from neurons located in the specific, nonspecific, and association thalamic nuclei using the retrograde axonal transport technique. The distribution, dimensions, and shape of the somata of relay neurons spread through the thalamic nuclei were analyzed. The total number of neurons sending out thalamo-sensorimotor-cortical fibers was calculated and the coordinates of loci with the highest density of these cells in each thalamic nucleus were identified. Multipolar and stellate cells with somata measuring 12–20 µm and 10–15 µm in diameter, respectively, prevailed amongst relay neurons. Amongst the specific nuclei, the majority of afferent fibers are sent out by the ventrolateral, ventral anterior, and anterior ventral nuclei. A comparable number of afferent fibers are sent out by the mediodorsal and paracentral nuclei; these split up among the association nuclei and paracentral nuclei, respectively. It is suggested that afferents from many different groups of thalamic nuclei are essential for the sensorimotor cortex to participate in thalamocortical interaction.Institute of Higher Nervous Activity and Neurophysiology, Academy of Sciences of the USSR, Moscow. Translated from Neirofiziologiya, Vol. 19, No. 1, pp. 87–94, January–February, 1987. 相似文献
109.
Reordering of the parameters of motor activity produced in the scratch generator by regular electrical stimulation of the ipsilateral hindlimb muscle nerve during different limb positions was investigated in decerebrate immobilized cats. Brief short latency inhibition of currently occurring motor activity was produced in response to stimulation, which did not cause an overall shift in the relationship between the intensity of aiming and scratching motion. Changes in cycle duration and intensity of these activities were phase-locked. Speculations were made on the functional role of the phase-locked nature of motor activity remodeling. The possible existence within the scratch generator of a model of the afferent inflow entering the spinal cord during true scratching is suggested.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 19, No. 3, pp. 382–390, May–June, 1987. 相似文献
110.
M. Mes-Hartree E. K. C. Yu I. D. Reid J. N. Saddler 《Applied microbiology and biotechnology》1987,26(2):120-125
Summary Enzymatic conversion of lignocellulosic material to fuels and chemicals depends on a initial pretreatment to render the cellulose more susceptible to enzymatic attack. Biological delignification of aspenwood with the fungus Phlebia tremellosus was compared to steaming as a pretreatment method.The biologically delignified aspenwood (BDA) had a high pentosan content and did not contain inhibitors of enzymatic hydrolysis or subsequent fermentation. In contrast, the steamed aspenwood required a water extraction step to remove the inhibitory material and this step also removed most of the pentosan. The yield of treated material was 90% from biological delignification and 70% from steaming.The cellulose in the BDA was less accessible to the cellulase enzymes than the steamed aspenwood. Combined hydrolysis and fermentation with Saccharomyces cerevisiae gave a lower yield of ethanol from BDA than from the steamed aspenwood, but the yields based on the weight of substrate before pretreatment were comparable. Combined hydrolysis and fermentation with Klebsiella pneumoniae gave higher yields of butanediol from BDA than from steamed aspenwood, because Klebsiella can ferment the xylose which was present in the biologically treated aspenwood. Trichoderma harzianum produced lower levels of cellulase enzymes when grown on BDA than when grown on steamed aspenwood and this was related to the xylan found in the biologically treated material.Abbreviations BDA
biologically delignified aspenwood
- SEA-WI
steam-exploded, water-extracted aspenwood
- AI-SEA-WI
acid-impregnated, steam-exploded, water-extracted aspenwood
- CHF
combined hydrolysis and fermentation
- FP
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