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31.
There is evidence that Japanese macaques (Macaca fuscata) are extremely sensitive to dynamic changes in the relative amplitudes of coo call harmonics during discrimination tests. To verify this evidence using more controlled stimulus configurations, the authors examined threshold sensitivity of macaque monkeys to amplitude increments added to the standard level of coo call harmonics. Psychophysical threshold determination methods paralleled those used previously to determine macaque sensitivity to amplitude increments added to vowel-like stimuli. Variation was detectable although thresholds were elevated relative to those obtained with vowel-like stimuli in another investigation (C. G. Le Prell, A. J. Niemiec, & D. B. Moody, 2001). This elevation was probably a function of natural amplitude modulation in the standard stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
Argues that any test of a model of human judgment must consider the possibility that the psychophysical functions for the stimulus variables are not the identity function and that rating scale responses are not a linear function of the S's impression. It is maintained that in their research on covariation judgment, D. M. Lane et al (1985) did not consider either of these possibilities. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
Karuza Jurgis; Zevon Michael A.; Gleason Timothy A.; Karuza Colleen M.; Nash Linda 《Canadian Metallurgical Quarterly》1990,5(2):194
The analysis of P. Brickman et al (see record 1982-30315-001), which separates attribution of a problem's cause and solution, was tested in 4 studies. Young and elderly adults' (n?=?210) well-being was related only to taking responsibility for solutions. The elderly compared with the young adults assumed less responsibility for problem cause and solution. They also preferred helping and coping models that assume low self-responsibility for solutions (e.g., medical model). This result was replicated with Meals on Wheels clients (n?=?51). An intragenerational helping pattern was found in Study 3. Lay helpers (n?=?63) helped mainly same-age recipients. Elderly and middle-aged helpers compared with young adults preferred using a medical model. Overall, a cohort bias in model preference was suggested. In Study 4, problem type and recipient age moderated attributions and model choice of young and middle-aged Ss (n?=?92). Relevance to the control literature and ethical and clinical implications of a medical-model bias are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
PURPOSE: The aim of this study was to compare the efficacy of hioxofilcon A and omafilcon A soft contact lenses for the reduction of signs and symptoms of contact lens related dryness among contact lens wearers who presented with symptoms and signs at baseline. METHODS: Forty dry eye subjects, 37 females and 3 males, were enrolled in this prospective, single-center, randomized, contra-lateral, cross-over study. Subjects were randomly dispensed hioxifilcon A and omafilcon A lenses for contra-lateral eyes. Lenses were worn daily wear for 3 months; for 6 weeks (2-week lens replacement) then lens types were crossed over to opposite eyes for 6 more weeks. Clinical examinations took place at baseline, 1 and 6 weeks in each cycle. Ocular surface signs and symptoms were evaluated by self-administered questionnaire. RESULTS: Compared to baseline symptoms with habitual lenses, dryness, discomfort, and blurry vision were reported at a lower frequency and intensity with both test lens types (p < 0.05, all comparisons, Wilcoxon Signed Ranks Test). Compared to baseline signs, there was an improvement in overall fluorescein staining for both lenses (p < 0.05). Lissamine green staining showed improvement with omafilcon A lenses only (p < 0.05). There was no change in tear break up time or bulbar redness. CONCLUSION: Symptoms and ocular surface staining associated with contact lens related dryness can be significantly alleviated by the use of hioxofilcon A or omafilcon A lenses, which yielded similar findings in this study. 相似文献
35.
A method to select and separate viable cells based on the results of a cell-lethal assay was developed. Cells were plated on an array of culture sites with each site composed of closely spaced, releasable micropallets. Clonal colonies spanning multiple micropallets on individual culture sites were established within 72 h of plating. Adjacent sites were widely spaced with 100% of the colonies remaining sequestered on a single culture site during expansion. A laser-based method mechanically released a micropallet underlying a colony to segment the colony into two genetically identical colonies. One portion of the segmented colony was collected with 90% efficiency while viability of both fractions was 100%. The segmented colonies released from the array were fixed and subjected to immunofluorescence staining of intracellular phospho-ERK kinase to identify colonies that were highly resistant or sensitive to phorbol ester-induced activation of ERK. These resistant and sensitive cells were then matched to the corresponding viable colonies on the array. Sensitive and resistant colonies on the array were released and cultured. When these cultured cells were reanalyzed for phorbol ester-induced ERK activity, the cells retained the sensitive or resistant phenotype of the originally screened subcolony. Thus, cells were separated and collected based using the result of a cell-lethal assay as selection criteria. These microarrays enabling clonal colony segmentation permitted sampling and manipulation of the colonies at very early times and at small cell numbers to reduce reagent, time, and manpower requirements. 相似文献
36.
37.
Many river rehabilitation projects to enhance the aquatic habitat focus on the creation of pool and riffle habitat by the implementation of flow deflectors, with various degrees of successes and failures. A more comprehensive understanding of the complex three‐dimensional flow dynamics that induces scour around instream structures is required for a more effective design. The objective of this study is to examine the three‐dimensional mean and turbulent flow characteristics around paired flow deflectors for various types of deflector design in a laboratory flume. Three deflector angles (45°, 90° and 135°) and two deflector heights (with flow under and over the deflector height) were tested over a smooth (plexiglas) bed and a sand bed. Three‐dimensional velocity measurements were taken with an acoustic Doppler velocimeter at several planform positions at two heights above the bed. Results show that the 90° deflectors create the most important disturbance in the mean flow field, in turbulence intensity and bed shear stress. There is, however, a marked difference in the spatial distribution of the mean and turbulent parameters over a mobile bed and over a smooth, fixed bed. This stresses the importance of understanding the feedback between bed topography and flow dynamics and limits the applicability of conclusions drawn from plane bed experiments to natural rivers. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
38.
Colleen Wade 《火与材料》1995,19(3):127-132
New Zealand Building Code Performance requirements relating to fire performance of external walls are considered and methods of evaluating the potential for vertical fire spread are discussed. Classifying external wall claddings on the basis of performance in the ‘combustibility’ test has proved overly restrictive where some external cladding materials are concerned. Performance criteria based on heat relase or ‘degree of combustibility’ are proposed and they seem to provide a better classification scheme for external wall cladding materials. Heat release test data for ten different external wall cladding materials are presented. 相似文献
39.
Orolingual dyskinetic effects of haloperidol were studied in rats trained to lick drops of water from a force-sensing disk. Haloperidol dose-dependently decreased force of tongue protrusion, decreased lick duration, increased interlick interval, and decreased number of licks. Fourier methods showed that haloperidol, in doses as low as 0.06 mg/kg, slowed the lick oscillations from an average of 5.250 Hz to 5.096 Hz (p?=?.014). Lick force was modulated by water drop delivery, but this effect was not influenced by haloperidol, which suggests no interference of the drug with sensory regulation of licking. The drug-induced deficits in tongue force may be manifestations of either postural alterations (pseudoparkinsonism) or orobuccolingual dyskinesias or both. Orolingual motor impairments may account for some of the neuroleptic-engendered behavioral decrements that have previously been explained in terms of reward, motivational deficits, or both. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Past research concluded that predictions of performance are a multiplicative function of ability and effort, although these studies were not designed to test between the averaging and multiplying models. The present study with 65 undergraduates competitively tested these models by manipulating the reliability of information about effort and ability. Results show that the greater the reliability of the ability information, the greater was its effect on judged performance. Similarly, the greater the reliability of the effort information, the greater was its effect on judged performance; in addition, the greater the reliability of 1 type of information, the less the effect of the other type of information. Findings are inconsistent with a multiplying model, but they are consistent with an averaging model in which the reliability of information influences its weight. Individual differences in weighting of effort and ability information were also found, and these differences were predictable from self-reports of the relative importance of the variables. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献