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161.
Adults and 9- to 11-mo-old infants listened to repeated transpositions of either a prototypical Western melody that was based on the major triad or a nonprototypical Western melody that was based on the augmented triad. In both cases, the transpositions were either to related keys (standing in a 2:3 frequency ratio) or to unrelated keys (more complex frequency ratios). For the prototypical melody, both infants and adults more readily discriminated a change to the melody in the context of related keys. For the nonprototypical melody, infant listeners performed better in the context of related keys, but adult listeners performed worse. The findings indicate that the global context of auditory patterns influences the processing of pattern details for infant and adult listeners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
162.
Laurel Kirkland Kenneth Herr Eric Keim Paul Adams John Salisbury John Hackwell Allan Treiman 《Remote sensing of environment》2002,80(3):447-459
In May 1999, the airborne thermal infrared hyperspectral imaging system, Spatially Enhanced Broadband Array Spectrograph System (SEBASS), was flown over Mormon Mesa, NV, to provide the first test of such a system for geological mapping. Several types of carbonate deposits were identified using the 11.25-μm band. However, massive calcrete outcrops exhibited weak spectral contrast, which was confirmed by field and laboratory measurements. Because the weathered calcrete surface appeared relatively smooth in hand specimen, this weak spectral contrast was unexpected. Here we show that microscopic roughness not readily apparent to the eye has introduced both a cavity effect and volume scattering to reduce spectral contrast. The macroroughness of crevices and cobbles may also have a significant cavity effect. The diminished spectral contrast is important because it places higher signal-to-noise ratio (SNR) requirements for spectroscopic detection and identification. This effect should be factored into instrumentation planning and interpretations, especially interpretations without benefit of ground truth. SEBASS had the required high SNR and spectral resolution to allow us to demonstrate for the first time the ability of an airborne hyperspectral thermal infrared scanner to detect and identify spectrally subtle materials. 相似文献
163.
J. Mark Ettinger 《Theoretical computer science》2000,230(1-2)
We define an extended real-valued metric, ρ, for positional games and prove that this class of games is a topological semigroup. We then show that two games are finitely separated iff they are path-connected and iff two closely related Conway games are equivalent. If two games are at a finite distance then this distance is bounded by the maximum difference of any two atoms found in the games. We may improve on this estimate when two games have the same form, as given by a form match. Finally, we show that if ρ(G,H)=∞ then for all X we have G+X H+X, a step towards proving cancellation for positional games. 相似文献
164.
An automatic registration method for frameless stereotaxy, image guided surgery, and enhanced reality visualization 总被引:6,自引:0,他引:6
Grimson WL Ettinger GJ White SJ Lozano-Perez T Wells WM Kikinis R 《IEEE transactions on medical imaging》1996,15(2):129-140
There is a need for frameless guidance systems to help surgeons plan the exact location for incisions, to define the margins of tumors, and to precisely identify locations of neighboring critical structures. The authors have developed an automatic technique for registering clinical data, such as segmented magnetic resonance imaging (MRI) or computed tomography (CT) reconstructions, with any view of the patient on the operating table. The authors demonstrate on the specific example of neurosurgery. The method enables a visual mix of live video of the patient and the segmented three-dimensional (3-D) MRI or CT model. This supports enhanced reality techniques for planning and guiding neurosurgical procedures and allows us to interactively view extracranial or intracranial structures nonintrusively. Extensions of the method include image guided biopsies, focused therapeutic procedures, and clinical studies involving change detection over time sequences of images. 相似文献
165.
As the U.S. geriatric population grows older, dentists should recognize the need to carefully consider age-related concerns that influence clinical decision-making. The authors discuss several prevalent problems typically found in "old-old" patients and propose a model for determining the appropriate extent of dental care for them. 相似文献
166.
167.
Michael T Lambert Jeffrey E Terrell Laurel A Copeland David L Ronis Sonia A Duffy 《Nicotine & tobacco research》2005,7(2):233-241
Tobacco exposure is a key risk factor for head and neck cancer, and continued smoking after diagnosis negatively affects outcomes. The present study examined tobacco smoking, nicotine dependence, alcohol use, and depression in survivors of head and neck cancer. Subjects at least 6 months post-initial diagnosis of head and neck cancer (N=694) drawn from three VA otolaryngology clinics (n=309, VA patients) and a university-based otolaryngology clinic (n=385, non-VA patients) were administered questionnaires and standardized rating instruments for nicotine and alcohol dependence and for depression. Additional clinical information was extracted from chart reviews. Despite high rates of prior smoking, less than one-quarter of all subjects continued to smoke. After controlling for significant confounding variables, we found that VA patients were more likely to be current smokers (OR=1.9, 95% CI=1.3-3.0), but current VA smokers did not differ significantly from non-VA smokers on the Fagerstr?m Test for Nicotine Dependence criterion (p=.69). The VA patients were more likely to screen positive for problem drinking on the Alcohol Use Disorder Identification Test (OR=2.1, 95% CI=1.3-3.7). After adjusting for other variables, we found no statistical difference between the groups in depression scores on the Geriatric Depression Scale-Short Form. The study provides data on smoking, alcohol use, and depression in head and neck cancer survivors indicating that VA patients are at increased risk for continued smoking and problem drinking relative to non-VA patients. Head and neck cancer patients benefit from aggressive smoking cessation efforts by the VA, but many patients need specialized services that integrate smoking interventions with treatment of comorbid alcoholism. 相似文献
168.
Early Susan J.; Mason Christine R.; Zheng Ling; Evilsizer Mary; Idrobo Fabio; Harrison J. Michael; Carney Laurel H. 《Canadian Metallurgical Quarterly》2001,115(3):650
A Pavlovian conditioned eyeblink response in rabbits (Oryctolagus cuniculus) was used to study psychoacoustical phenomena previously demonstrated in human listeners and other animals. This article contains the results of a tone-in-noise detection study to examine 2 psychoacoustical phenomena in rabbit and in human listeners: (a) the binaural masking level difference (BMLD) and (b) differential performance across reproducible noise masker waveforms. The rabbits demonstrated a BMLD comparable in size to other species. Significant differences in performance across reproducible noise masker waveforms were seen in the rabbits. This performance was compared with the performance of human listeners using the same set of waveforms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
169.
Land suitability analysis for the upper Gila River watershed 总被引:7,自引:0,他引:7
In the United States, federal management agencies, such as the U.S. Forest Service and the U.S. Bureau of Land Management are required to assess the capability of land for future use. In addition, Arizona law now requires local jurisdictions to prepare comprehensive and general plans. Suitability analysis can be used for compliance with several elements of these plans. Here, a framework for land suitability analysis is presented for the upper Gila River watershed in Arizona and New Mexico. The framework is based on a thorough ecological inventory of the watershed. A goal of suitability analysis is to explicitly identify constraints and opportunities for future land conservation and development. This is accomplished by determining the fitness of a given tract of land for a defined use. Four land uses were targeted by local officials for analysis: low-density housing, commercial development, industrial development, and recreation. The framework can be useful for natural resource management as well as town, city, county, and federal planning in the watershed. 相似文献
170.
R.D. Ettinger F.A. Fernandez B.M.A. Rahman J.B. Davies 《Photonics Technology Letters, IEEE》1991,3(2):147-149
A numerical solution is given for nonlinear optical waveguides with power confinement in both transverse dimensions. Self-consistent solutions are obtained by using an accurate vector-finite-element formulation along with the penalty technique. Numerical results for the first quasi-transverse-magnetic power-dependent mode are presented for strip-loaded waveguides with saturable self-focusing media. The variations with total power are illustrated for the modal index and for the fraction of the total power carried by different regions, showing interesting abrupt power switching for realistic geometries. It is shown that the switching effect is maintained in the presence of saturation and over a range of two-transverse-dimensions geometries. This switching effect can be controlled with variation of some of the parameters of the guide.<> 相似文献