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51.
Whether Ss can attend to physical dimensions of objects without access to semantic information about them was examined. Ss decided which of 2 laterally presented pictures, a target and a distractor, had the same orientation (Exp 1), size (Exp 2), luminance (Exp 3), or color (Exp 4) as a reference picture. In each experiment, the matching stimuli were either physically identical, semantically related, or semantically unrelated. The reference stimulus and the distractor were either semantically related or unrelated. When matching was based on orientation or on size, performance was facilitated when the matching stimuli were semantically related, and it was disrupted when the distractor was semantically related to the reference stimulus. Semantic effects were eliminated when matching was based on luminance or color. The results are discussed in terms of physiological data, form and surface information, and global and local processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
A growing group of institutions and individuals use Internet connections to reach information sources. Large health care organizations now see electronic records as essential to providing cost-effective health care. The Visible Human Project represents the entire three-dimensional anatomy of a cadaver. 相似文献
53.
We describe how coplanar microwave resonators fabricated from patterned thin films of YBa2Cu3O7(-δ) (YBCO) can he used to measure the ab-plane microwave surface impedance Zs=Rs+jXs of the films, in particular the absolute value and temperature dependence of the magnetic penetration depth λ. The current distribution of the resonator is calculated by modelling the resonator as a network of coupled transmission lines of rectangular cross-sections; this is then used to estimate the ab-plane λ(T) from the measurements of resonators of different geometries patterned onto the same film. We obtain values of λ(0) in the range 150-220 nm. The unloaded quality factors of the linear resonators at 7.95 GHz are around 45000 at 15 K and around 6500 at 77 K. We estimate the corresponding values of the intrinsic Rs at 7.95 GHz to be 23 μΩ and 110 μΩ at 15 K and 77 K, respectively. These values are comparable with those of other high quality unpatterned YBCO films reported in the literature. Zs for the best optimised films appears to be insensitive to the effects of patterning 相似文献
54.
Four experiments are reported examining the locus of structural similarity effects in picture recognition and naming with normal subjects. Subjects carried out superordinate categorization and naming tasks with picture and word forms of clothing, furniture, fruit, and vegetable exemplars. The main findings were as follows: (1) Responses to pictures of fruit and vegetables ("structurally similar" objects) were slowed relative to pictures of clothing and furniture ("structurally dissimilar" objects). This structural similarity difference was greater for picture naming than for superordinate categorization of pictures. (2) Structural similarity effects in picture naming were reduced by repetition priming. Repetition priming effects were equivalent from picture and word naming as prime tasks. (3) However, superordinate categorization of the prime did not produce the structural similarity effects on priming found for picture naming. Furthermore, such priming effects did not arise for picture or word categorization or for reading picture names as target tasks. It is proposed that structural similarity effects on priming object processing are located in processes mapping semantic representations of pictures to name representations required to select names for objects. Visually based competition between fruit and vegetables produces competition in name selection, which is reduced by priming the mappings between semantic and name representations. 相似文献
55.
F. J. Humphreys 《Journal of microscopy》2004,213(3):247-256
Electron backscatter diffraction maps are capable of yielding a substantial amount of quantitative information about grains, subgrains and boundaries, and the amount and quality of the data may be substantially increased if the pixels of the map are re‐analysed so as to ‘reconstruct’ complete grains or subgrains. The paper discusses the various methods of grain reconstruction and the use of such methods to obtain microstructural information correlating the parameters of dimension, position, orientation and misorientation, which cannot usually be obtained by other means. Grain reconstruction also reveals the nature, location and contacts of all the triple junctions in the microstructure, and the paper discusses two important examples of how these data may be further analysed using automated routines. Boundary connectivity and the length and direction of likely paths along which grain boundary events such as creep fracture or stress corrosion may occur can readily be determined. The overall alignment of boundaries in deformed metals, with respect to the crystallography and the deformation geometry, may be determined as a function of the length and misorientation of the boundary segments. 相似文献
56.
This analysis explores the pattern of variation of the desired thermal sensation on the ASHRAE scale, applying the method of direct enquiry. Data are from studies of thermal comfort at university lectures and in selected dwellings. Respondents reported both their thermal sensation and the sensation they would have desired at that time. The data contain 868 comparisons of the actual and the desired sensation. On 57% of occasions the desired sensation was other than ‘neutral’. The respondents did not always desire the same sensation, and the mean desired sensation differed systematically among the respondents. The mean desired sensation depended to some extent on the actual sensation, there being a positive correlation in the region from ‘neutral’ and ‘warm’ and a negative correlation outside this region. Sensations on the ASHRAE scale are shown to have more than one meaning. Adjusting the ASHRAE scale to allow for the desired sensation yields different distributions of thermal comfort and different group-optimum temperatures. The adjustment should therefore be applied whenever the ASHRAE scale is used. The implications for thermal simulation and for energy use in buildings are considered. 相似文献
57.
The present study was designed to apply the mass defect filter (MDF) approach to the screening and identification of reactive metabolites using high-resolution mass spectrometry. Glutathione (GSH)-trapped reactive metabolites of acetaminophen, diclofenac, carbamazepine, clozapine, p-cresol, 4-ethylphenol, and 3-methylindole in human liver microsomes (HLM) were analyzed by HPLC coupled with Orbitrap or Fourier transform ion cyclotron resonance mass spectrometry. Through the selective removal of all ions that fall outside of the GSH adduct MDF template windows, the processed full scan MS chromatograms displayed GSH adducts as major components with no or a few interference peaks. The accurate mass LC-MS data sets were also utilized for the elimination of false positive peaks, detection of stable oxidative metabolites with other MDF templates, and determination of metabolite molecular formulas. Compared to the neutral loss scan by a triple quadrupole instrument, the MDF approach was more sensitive and selective in screening for GSH-trapped reactive metabolites in HLM and rat bile and far more effective in detecting GSH adducts that do not afford the neutral loss of 129 Da as a significant fragmentation pathway. The GSH adduct screening capability of the MDF approach, together with the utility of accurate mass MS/MS information in structural elucidation, makes high-resolution LC-MS a useful tool for analyzing reactive metabolites. 相似文献
58.
The convergent beam electron diffraction (CBED) methodology was developed to investigate the lattice distortions in wurtzite gallium nitride (GaN) from a single zone-axis pattern. The methodology enabled quantitative measurements of lattice distortions (α, β, γ and c) in transmission electron microscope (TEM) specimens of a GaN film grown on (0, 0, 0, 1) sapphire by metal-organic vapour-phase epitaxy. The CBED patterns were obtained at different distances from the GaN/sapphire interface. The results show that GaN is triclinic above the interface with an increased lattice parameter c. At 0.85 μm from the interface, α=90°, β=8905° and γ=11966°. The GaN lattice relaxes steadily back to hexagonal further away from the sapphire substrate. The GaN distortions are mainly confined to the initial stages of growth involving the growth and the coalescence of 3D GaN islands. 相似文献
59.
The effect of solutes (Si, Mn, Mg) in quantities typical of commercial aluminium alloys, on grain boundary mobility in aluminium, has been investigated with in situ annealing and electron backscattered diffraction in the SEM, and grain growth experiments. The in situ experiments provided information on the migration of the high mobility tilt boundaries of misorientations close to 40°〈1 1 1〉. Grain growth experiments were used to investigate boundary migration in alloys of high solute content (1-5wt%Mg), and a comparison between the in situ and bulk experiments is made. The relationship between boundary velocity and driving pressure was found to be linear in all cases, and the activation energies for boundary migration were higher than those controlled by lattice diffusion of the solutes at higher solute concentrations. 相似文献
60.
Humphreys Michael S.; Maguire Angela M.; McFarlane Kimberley A.; Burt Jennifer S.; Bolland Scott W.; Murray Krista L.; Dunn Ryan 《Canadian Metallurgical Quarterly》2010,36(1):147
We examined associative and item recognition using the maintenance rehearsal paradigm. Our intent was to control for mnemonic strategies; to produce a low, graded level of learning; and to provide evidence of the role of attention in long-term memory. An advantage for low-frequency words emerged in both associative and item recognition at very low levels of learning. This early emergence casts doubt on explanations based on the traditional concept of recollection. A comparison of false alarms supports a role for item information or the joint use of cues but not familiarity in producing associative false alarms. We may also have found a way to measure the amount of attention being paid to a to-be-learned item or pair, independently of memory performance on the attended item. This result may be an important step in determining whether coherent theories about the role of attention in long- and short-term memory can be created. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献