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71.
Evaluated the Psychiatric Rehabilitation Attitude Survey (PRAS) by the 1st author and A. Sklare-Lancaster (1981) in 2 experiments. In Exp I, reliability and validity data of the PRAS were assessed, using 37 vocational rehabilitation practitioners. Results indicate that test–retest reliability was high and that convergent and divergent validity were adequate compared with the Attitudes Toward Disabled Persons Scale and the Marlowe-Crowne Social Desirability Scale. Exp II assessed the effect of a 4-wk field placement on the attitudes of 48 undergraduate rehabilitation psychology majors. There was a significant positive change in Ss' attitudes toward psychiatric rehabilitation, and their scores after field placement were significantly more positive than norms obtained from general-caseload rehabilitation practitioners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Using the clinical linguistic and auditory milestone scale for developmental screening in high-risk preterm infants 总被引:1,自引:0,他引:1
Eighty-one preterm infants (mean gestational age 29 weeks, range 24-36 weeks) discharged from The Johns Hopkins Hospital Neonatal Intensive Care Unit were followed up sequentially from birth to 2 years of age by use of the Clinical Linguistic and Auditory Milestone Scale (CLAMS) to evaluate language development. Children were studied during three time intervals: Interval 1: 3-5 months chronologic age (CA); Interval 2: 9-14 months (CA); and Interval 3: 18-24 months (CA). Psychometric test scores were compared with CLAMS Language Quotients (LQ) by use of full, partial (75%, 50%, 25%), and no "correction" for weeks of prematurity to determine whether "correcting" for prematurity would yield a more accurate estimate of eventual cognitive outcome. CLAMS LQ at Interval 1 was highly correlated with CLAMS LQ at Interval 2 and CLAMS LQ at Interval 2 correlated well with CLAMS LQ at Interval 3 (r = 0.57 and 0.64, respectively, P = 0.0001). Correlations indicated that there was an orderly, sequential development of language in the preterm infant. CLAMS evaluations correlated significantly with psychometric test results during Interval 2 and Interval 3 (r = 0.34, P < 0.02 and r = 0.75, P = 0.0001, respectively). The CLAMS proved to be a useful instrument for monitoring preterm language development in the primary pediatric care setting. 相似文献
73.
74.
Using the scanning probe technique known as Kelvin probe force microscopy it is possible to successfully devise a sensor for charged biomolecules. The Kelvin probe force microscope is a tool for measuring local variations in surface potential across a substrate of interest. Because many biological molecules have a native state that includes the presence of charge centres (such as the negatively charged backbone of DNA), the formation of highly specific complexes between biomolecules will often be accompanied by local changes in charge density. By spatially resolving this variation in surface potential it is possible to measure the presence of a specific bound target biomolecule on a surface without the aid of special chemistries or any form of labelling. The Kelvin probe force microscope presented here is based on an atomic force microscopy nanoprobe offering high resolution (<10 nm), sensitivity (<50 nM) and speed (>1,100 microm s(-1)), and the ability to resolve as few as three nucleotide mismatches. 相似文献
75.
Bubbles that form in the tissues and bloodstreams of animals and humans undergoing a compression/decompression sequence are considered precursors to symptoms of decompression sickness. A prevalent method used to monitor these bubbles is to ensonify the pulmonary artery or inferior vena cava with ultrasound and listen for Doppler shifted signals in the reflected and scattered sound. 相似文献
76.
Most Steven B.; Laurenceau Jean-Philippe; Graber Elana; Belcher Amber; Smith C. Veronica 《Canadian Metallurgical Quarterly》2010,10(2):250
Does the influence of close relationships pervade so deeply as to impact visual awareness? Results from two experiments involving heterosexual romantic couples suggest that they do. Female partners from each couple performed a rapid detection task where negative emotional distractors typically disrupt visual awareness of subsequent targets; at the same time, their male partners rated attractiveness first of landscapes, then of photos of other women. At the end of both experiments, the degree to which female partners indicated uneasiness about their male partner looking at and rating other women correlated significantly with the degree to which negative emotional distractors had disrupted their target perception during that time. This relationship was robust even when controlling for individual differences in baseline performance. Thus, emotions elicited by social contexts appear to wield power even at the level of perceptual processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
B. Kamgar-Parsi B. Johnson D. L. Folds E. O. Belcher 《International journal of imaging systems and technology》1997,8(4):377-385
In recent years, several sonars designed for high-resolution, short-range underwater imaging have been developed. These imaging systems use an acoustic lens to focus the incoming waves on an array of transducers. In this article we describe three prototype systems that use a line-focus or a point-focus lens and operate at a frequency of 300 kHz or 3 MHz. The line-focus lens produces two-dimensional (2D) intensity images, while the point-focus lens produces 3D intensity images. We present sample images taken from moving and stationary platforms, and discuss the techniques used for processing the acoustic backscatter data to reconstruct and visualize the scene. The images, particularly those taken with a point-focus lens, show a remarkable degree of detail. © 1997 John Wiley & Sons, Inc. Int J Imaging Syst Technol, 8, 377–385, 1997 相似文献
78.
Nathan CoolingKerry B. Burke Xiaojing ZhouSamuel J. Lind Keith C. GordonTimothy W. Jones Paul C. DastoorWarwick J. Belcher 《Solar Energy Materials & Solar Cells》2011,95(7):1767-1774
A series of three porphyrins varying only in the steric bulk of their peripheral groups have been synthesised and integrated into the active layer of bulk heterojunction solar cells. The porphyrins broaden the spectral response of the device and contribute to the total photocurrent generated. More importantly, the device characteristics change systematically with increasing steric bulk on the peripheral meso phenyl groups of the tetra-phenyl porphyrin. Optical, scanning probe and scanning transmission X-ray microscopy are used to demonstrate that the observed changes do not arise from morphological differences in film structure. Cyclic voltammetry, UV-vis spectroscopy and DFT calculations are used to establish that the porphyrin LUMO, HOMO and bandgap are independent of side group. We conclude that the variations in open-circuit voltage with side group are the result of the porphyrin acting as a bimolecular recombination centre, with an efficiency that is dependent on the side group type. The possibility of designing optimised macromolecules for OPV devices based on an understanding the effect of porphyrin steric bulk upon device performance is discussed. 相似文献
79.
Shengnan Huang Jifa Qi Dane W. deQuilettes Mantao Huang Ching‐Wei Lin Neelkanth M. Bardhan Xiangnan Dang Vladimir Bulovi Angela M. Belcher 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(28)
Fluorescence imaging is a powerful tool for studying biologically relevant macromolecules, but its applicability is often limited by the fluorescent probe, which must demonstrate both high site‐specificity and emission efficiency. In this regard, M13 virus, a versatile biological scaffold, has previously been used to both assemble fluorophores on its viral capsid with molecular precision and to also target a variety of cells. Although M13‐fluorophore systems are highly selective, these complexes typically suffer from poor molecular detection limits due to low absorption cross‐sections and moderate quantum yields. To overcome these challenges, a coassembly of the M13 virus, cyanine 3 dye, and silver nanoparticles is developed to create a fluorescent tag capable of binding with molecular precision with high emissivity. Enhanced emission of cyanine 3 of up to 24‐fold is achieved by varying nanoparticle size and particle‐fluorophore separation. In addition, it is found that the fluorescence enhancement increases with increasing dye surface density on the viral capsid. Finally, this highly fluorescent probe is applied for in vitro staining of E. coli. These results demonstrate an inexpensive framework for achieving tuned fluorescence enhancements. The methodology developed in this work is potentially amendable to fluorescent detection of a wide range of M13/cell combinations. 相似文献
80.
The m2 muscarinic acetylcholine receptor in the cerebral cortex has traditionally been thought of as an autoreceptor located on cholinergic fibers that originate from neurons in the nucleus basalis of Meynert. We now provide evidence for widespread localization of the m2 receptor in noncholinergic neurons and fibers of the cerebral cortex. The cellular and subcellular distribution of the m2 receptor protein and mRNA were examined in normal monkeys and in monkeys in which the cortical cholinergic afferents were selectively lesioned by injection of the specific immunotoxin, anti-p75NTR-saporin into the nucleus basalis. Both in normal and immunolesioned monkeys, the m2 mRNA and protein were localized in pyramidal and nonpyramidal neurons. In pyramidal neurons, membrane-associated receptor immunoreactivity was found exclusively in dendritic spines receiving asymmetric synapses, indicating that the m2 receptor may modulate excitatory neurotransmission at these sites. In nonpyramidal neurons, the m2 immunoreactivity was present along the cytoplasmic surface of membranes in cell bodies, dendrites and axons. Both in pyramidal and nonpyramidal neurons of normal and lesioned monkeys, the m2 receptor was located peri- and extra-synaptically, suggesting that it may be contacted by acetylcholine via volume transmission. The localization of the m2 receptor in cortical neurons and the sparing of m2 immunoreactivity in lesioned monkeys indicates that the m2 receptor is synthesized largely within the cortex and/or is localized to noncholinergic terminals of either intrinsic or extrinsic origin. These findings open the possibility that the loss of the m2 receptor in Alzheimer's disease may in part be due to degenerative changes in m2 positive neurons of the cortex rather than entirely due to the loss of autoreceptors. 相似文献