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101.
Tested 9 deaf and 9 normal 15-27 yr olds on their ability to report letters, shapes, and nonsense figures from a tachistoscopic presentation. Deaf Ss performed worse than hearing Ss on recall of figural information, thereby supporting a linguistic coding hypothesis. However, there was no difference between the groups on position information, and letter confusions were primarily visual in both groups. Findings suggest that more attention should be given to visual short-term memory in theoretical models of memory. Formation of the icon was apparently not affected by a linguistic deficit, since effects of stimulus duration and type of viewing (continuous vs interrupted) were similar in both hearing and deaf Ss. Significant positive correlations which were found between deaf Ss' school reading scores and their tachistoscopic scores were not interpreted as support for a linguistic coding hypothesis, but rather as support for the notion that the memory skills tested in the experiment may underlie reading ability. (French summary) (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Graham F. Carey David L. Humphrey 《International journal for numerical methods in engineering》1981,17(11):1717-1734
Global and element residuals are introduced to determine a posteriori, computable, error bounds for finite element computations on a given mesh. The element residuals provide a criterion for determining where a finite element mesh requires refinement. This indicator is implemented in an algorithm in a finite element research program. There it is utilized to automatically refine the mesh for sample two-point problems exhibiting boundary layer and interior layer solutions. Results for both linear and nonlinear problems are presented. An important aspect of this investigation concerns the use of adaptive refinement in conjunction with iterative methods for system solution. As the mesh is being enriched through the refinement process, the solution on a given mesh provides an accurate starting iterate for the next mesh, and so on. A wide range of iterative methods are examined in a feasibility study and strategies for interweaving refinement and iteration are compared. 相似文献
103.
DNA aptamer-based bioanalysis of IgE by fluorescence anisotropy 总被引:3,自引:0,他引:3
Gokulrangan G Unruh JR Holub DF Ingram B Johnson CK Wilson GS 《Analytical chemistry》2005,77(7):1963-1970
A rapid, homogeneous aptamer-based bioanalysis is reported for the sensitive detection of immunoglobulin E (IgE) using fluorescence polarization (FP). 5'-End-labeled D17.4 DNA aptamer was used for IgE detection based on the anisotropy differences of the labeled ligand. Two different fluorophores, fluorescein and Texas Red, were used to analyze IgE in the low-nanomolar range with high specificity. Measurable anisotropy changes were observed with a short equilibration time. Analysis of the binding data reveals a possible cooperative binding process in solution. The nature of the fluorophore clearly influences the sensitivity of the analysis more than the tether length used for the dye conjugation. The local fluorophore motion is seen to influence the sensitivity of the FP probe significantly. Texas Red is seen to be relatively more sensitive for this approach and has apparently favorable dye-DNA interactions, and a limit of detection of 350 pM was obtained. Significant temperature dependence of the FP responses has been observed in this work. Ionic composition of the binding buffer also influences the assay sensitivity. The results confirm the promise and potential of similar homogeneous assays for aptamer-based bioanalysis. 相似文献
104.
Wright P Garcia-Stewart CA Carey SJ Hindle FP Pegrum SH Colbourne SM Turner PJ Hurr WJ Litt TJ Murray SC Crossley SD Ozanyan KB McCann H 《Applied optics》2005,44(31):6578-6592
Design requirements for an 8000 frame/s dual-wavelength ratiometric chemical species tomography system, intended for hydrocarbon vapor imaging in one cylinder of a standard automobile engine, are examined. The design process is guided by spectroscopic measurements on iso-octane and by comprehensive results from laboratory phantoms and research engines, including results on temporal resolution performance. Novel image reconstruction techniques, necessary for this application, are presented. Recent progress toward implementation, including details of the optical access arrangement employed and signal-to-noise issues, is described. We present first cross-cylinder IR absorption measurements from a reduced channel-count (nontomographic) system and discuss the prospects for imaging. 相似文献
105.
Ergonomics is a key issue in the construction industry. Many work tasks and associated equipment and tools are not designed with ergonomics principles in mind. Often, in the development of power tools for construction, any attention to ergonomics is restricted to the human-machine interface and handle design. The need for ergonomics intervention in the development process originates from considerations of safety, health, physical work load, and productivity. It is argued that in each of these respects, the construction industry has lower standards than other industries and therefore has a need and opportunity for improvement. A multi-level ergonomics approach is proposed addressing these issues. The approach defines five levels of ergonomics intervention, from designing individual tools for safety, to designing wider aspects of construction and work flow for optimal productivity. This holistic approach is illustrated using case study examples of the development of power tools and work methods. 相似文献
106.
107.
Suggests that the government should sustain science, give it a voice in the councils of public policy, and link its versatility to the ends of a purposeful society. This function has 5 implications for public policy, planning, resource allocation, and administration in science. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
A simple analytical model is used to examine the mechanical interaction of LMFBR core components with the surrounding coolant. Approximating a subassembly duct by a single degree of freedom oscillator and the coolant by a thin layer of viscous fluid, the problem was reduced to a nonlinear differential equation governing the motion of the oscillator. Approximate analytical and numerical solutions are presented which enable parametric studies useful in LMFBR core design. 相似文献
109.
110.