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1.
Examined the phonological awareness skills of dyslexic children, adults with childhood diagnoses of dyslexia, and good readers at various age levels. Comparisons of the dyslexics to good readers of the same age or the same reading level indicated that dyslexics do not acquire appropriate levels of phoneme awareness, regardless of their age or reading levels, although they eventually acquire appropriate levels of onset-rhyme awareness. Even adults with fairly high levels of word recognition skill show phoneme awareness deficits. For normal readers, reliable increases in phoneme awareness were associated with age and reading level, whereas for dyslexic Ss these associations were not reliable. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
The field of children's testimony is in turmoil, but a resolution to seemingly intractable debates now appears attainable. In this review, we place the current disagreement in historical context and describe psychological and legal views of child witnesses held by scholars since the turn of the 20th century. Although there has been consistent interest in children's suggestibility over the past century, the past 15 years have been the most active in terms of the number of published studies and novel theorizing about the causal mechanisms that underpin the observed findings. A synthesis of this research posits three "families" of factors--cognitive, social, and biological--that must be considered if one is to understand seemingly contradictory interpretations of the findings. We conclude that there are reliable age differences in suggestibility but that even very young children are capable of recalling much that is forensically relevant. Findings are discussed in terms of the role of expert witnesses. 相似文献
3.
Shabana Vohra Bruck Taddese Alex C. Conner David R. Poyner Debbie L. Hay James Barwell Philip J. Reeves Graham J. G. Upton Christopher A. Reynolds 《Journal of the Royal Society Interface》2013,10(79)
Modelling class B G-protein-coupled receptors (GPCRs) using class A GPCR structural templates is difficult due to lack of homology. The plant GPCR, GCR1, has homology to both class A and class B GPCRs. We have used this to generate a class A–class B alignment, and by incorporating maximum lagged correlation of entropy and hydrophobicity into a consensus score, we have been able to align receptor transmembrane regions. We have applied this analysis to generate active and inactive homology models of the class B calcitonin gene-related peptide (CGRP) receptor, and have supported it with site-directed mutagenesis data using 122 CGRP receptor residues and 144 published mutagenesis results on other class B GPCRs. The variation of sequence variability with structure, the analysis of polarity violations, the alignment of group-conserved residues and the mutagenesis results at 27 key positions were particularly informative in distinguishing between the proposed and plausible alternative alignments. Furthermore, we have been able to associate the key molecular features of the class B GPCR signalling machinery with their class A counterparts for the first time. These include the [K/R]KLH motif in intracellular loop 1, [I/L]xxxL and KxxK at the intracellular end of TM5 and TM6, the NPXXY/VAVLY motif on TM7 and small group-conserved residues in TM1, TM2, TM3 and TM7. The equivalent of the class A DRY motif is proposed to involve Arg2.39, His2.43 and Glu3.46, which makes a polar lock with T6.37. These alignments and models provide useful tools for understanding class B GPCR function. 相似文献
4.
This paper presents a potential alternate method for determining operating capacity of motor-operated valves subjected to seismic and other applicable loadings. As a result of programs at nuclear facilities to ensure the operational capability of MOVs (under NRC GL89-10), extensive analytical focus to develop the structural capability of valves has ensued. In the past, seismic qualification of valves typically addressed the strength of the topwork structure to resist inertial loading from excitation of the large valve actuator mass. These evaluations paid little or no consideration to the loading resulting from valve closing forces. The focus of the recent efforts is to develop the maximum operational capability of the valve, in terms of thrust, with consideration of seismic and other services loading as applicable. The alternate method outlined in this paper presents a series of thrust capacity curves, with reduction factors for seismic loading which can be applied and developed to determine safe thrust loadings without performing extensive analytical effort. A similar approach was put forward by the SQUG GIP approach to MOVs to ensure the safe operation of valves based on past earthquake experience. However, the GIP approach cannot be used to determine safe operational loads and thus has limited use in the necessary analysis required for GL89-10 programs at nuclear facilities. 相似文献
5.
Previous research using monitoring tasks suggests that syllables do not play a role in the initial processing of speech by English listeners. The role of syllables in a different task, 1 involving the speeded comparison of 2 nonwords, was investigated. In 2 experiments, responses to nonword pairs that shared a complete syllable were significantly faster than responses to pairs that shared part of a syllable when the shared unit was at the beginning or in the middle of the nonwords. Results were mixed when the shared unit was at the end of the nonwords, possibly reflecting a confounding effect of rhyme. Findings suggest that syllabified representations of the nonwords may be used in a comparison task, even in English. Results are interpreted relative to different demands of the nonword comparison and monitoring tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
7.
Schwartz M. Bruck J. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2008,54(5):2179-2195
We address the well-known problem of determining the capacity of constrained coding systems. While the one-dimensional case is well understood to the extent that there are techniques for rigorously deriving the exact capacity, in contrast, computing the exact capacity of a two-dimensional constrained coding system is still an elusive research challenge. The only known exception in the two-dimensional case is an exact (however, not rigorous) solution to the -run-length limited (RLL) system on the hexagonal lattice. Furthermore, only exponential-time algorithms are known for the related problem of counting the exact number of constrained two-dimensional information arrays. We present the first known rigorous technique that yields an exact capacity of a two-dimensional constrained coding system. In addition, we devise an efficient (polynomial time) algorithm for counting the exact number of constrained arrays of any given size. Our approach is a composition of a number of ideas and techniques: describing the capacity problem as a solution to a counting problem in networks of relations, graph-theoretic tools originally developed in the field of statistical mechanics, techniques for efficiently simulating quantum circuits, as well as ideas from the theory related to the spectral distribution of Toeplitz matrices. Using our technique, we derive a closed-form solution to the capacity related to the Path-Cover constraint in a two-dimensional triangular array (the resulting calculated capacity is ). Path-Cover is a generalization of the well known one-dimensional -RLL constraint for which the capacity is known to be . 相似文献
8.
Bruck J. Blaum M. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1989,35(5):976-987
Several ways of relating the concept of error-correcting codes to the concept of neural networks are presented. Performing maximum-likelihood decoding in a linear block error-correcting code is shown to be equivalent to finding a global maximum of the energy function of a certain neural network. Given a linear block code, a neural network can be constructed in such a way that every codeword corresponds to a local maximum. The connection between maximization of polynomials over the n -cube and error-correcting codes is also investigated; the results suggest that decoding techniques can be a useful tool for solving such maximization problems. The results are generalized to both nonbinary and nonlinear codes 相似文献
9.
Ni-Al2O3 composites containing 0 to 100 vol % Ni were fabricated using powder processing techniques. By varying the metal : ceramic particle size ratio, either particle-reinforced or interpenetrating-phase microstructures were obtained. The mechanical properties of the composites were characterized and compared with rule-of-mixtures (ROM) predictions. For certain particle-reinforced composites, the elastic moduli measured ultrasonically did not obey the ROM. This result was attributed to the presence of damage that could be accounted for using existing models. In four-point bending, most composites exhibited linear elastic behavior, however significant inelastic deformation was observed for composites containing 60 and 80 vol % Ni. The inelastic deformation was reasonably well described using ROM models, except when substantial damage was present. Damaged materials were modeled as two phase composites containing one damage-free phase and one completely damaged phase that was assumed to behave like a porous material. The failure strains of composites with continuous ceramic phases were explained using a semi-empirical model that included both damage and residual stress effects. Fracture stresses were calculated from predicted fracture strains using a new ROM deformation model. The model was modified to include constraint effects in order to accurately describe the deformation behavior of the ductile continuous-ceramic composites. 相似文献
10.
Franceschetti M. Bruck J. 《Parallel and Distributed Systems, IEEE Transactions on》2001,12(11):1190-1200
Presents a solvable specification and gives an algorithm for the group membership problem in asynchronous systems with crash failures. Our specification requires processes to maintain a consistent history in their sequences of views. This allows processes to order failures and recoveries in time and simplifies the programming of high level applications. Previous work has proven that the group membership problem cannot be solved in asynchronous systems with crash failures. We circumvent this impossibility result building a weaker, yet nontrivial specification. We show that our solution is an improvement upon previous attempts to solve this problem using a weaker specification. We also relate our solution to other methods and give a classification of progress properties that can be achieved under different models 相似文献