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The naming of manipulable objects in older and younger adults was evaluated across auditory, visual, and multisensory conditions. Older adults were less accurate and slower in naming across conditions, and all subjects were more impaired and slower to name action sounds than pictures or audiovisual combinations. Moreover, there was a sensory by age group interaction, revealing lower accuracy and increased latencies in auditory naming for older adults unrelated to hearing insensitivity but modest improvement to multisensory cues. These findings support age-related deficits in object action naming and suggest that auditory confrontation naming may be more sensitive than visual naming. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
Experiments are described in which cotton fabrics at different stages of chemical processing were abraded to different extents on a Wira Abrasion Tester with three different abradants, namely, a smooth paper, a similar paper with a rough unfinished surface, and a standard worsted fabric. The three different plain-weave cotton fabrics selected were (a) desized and scoured, (b) bleached and mercerized, and (c) dyed and resin-treated. Scanning electron microscopy revealed that progressive chemical finishing, especially resin-finishing, reduced the abrasion-resistance of these fabrics. The rate of attrition of the cellulosic material at the surface of the fabric was much faster for rough paper than for a smoother type of paper abradant. The crossbred-worsted abradant was less severe than paper in its abrasive action. It also produced, in general, a more fuzzy fabric surface, with several loose fibre ends on the surface. Resin-treated fabrics had fewer of these loose surface fibres than the other two samples, particularly the scoured fabric, which had the most. In the resin-treated fabric, the abraded single fibre ends did not exhibit any twisting, whereas this characteristic feature was rather extensive in the non-resin-finished samples. The lack of twisting and rolling of the fibres probably arose from the constraints imposed by the resin crosslinks, which made the fibres more rigid and caused them to tend to fracture or rupture sharply rather than fibrillate over a somewhat extended length. 相似文献
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When taking multiple-choice tests of reading comprehension such as the Scholastic Assessment Test (SAT), test takers use a range of strategies that vary in the extent to which they emphasize reading the questions versus reading the passages. Researchers have challenged the construct validity of these tests because test takers can achieve better-than-chance performance even if they do not read the passages at all. By using an individual-differences approach that compares the relative power of working memory span to predict SAT performance for different test-taking strategies, the authors show that the SAT appears to be tapping reading comprehension processes as long as test takers engage in at least some reading of the passages themselves. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Enzymatic modification of trilinolein: Incorporation of n-3 polyunsaturated fatty acids 总被引:2,自引:0,他引:2
Casimir C. Akoh Brenda H. Jennings Dorris A. Lillard 《Journal of the American Oil Chemists' Society》1995,72(11):1317-1321
Two immobilized lipases, IM60 fromMucor miehei and SP435 fromCandida antarctica, were used as biocatalysts for the modification of trilinolein with n-3 polyunsaturated fatty acids (PUFA), such as eicosapentaenoic
acid (EPA) and docosahexaenoic acid (DHA), by using their ethyl esters as acyl donors (EEPA and EDHA, respectively). Transesterification
(ester-ester interchange) reactions were carried out in organic solvent. The products were analyzed according to their equivalent
carbon number and polarity by reverse-phase high-performance liquid chromatography, and the fatty acid profiles were determined
by gas-liquid chromatography. Modified triacylglycerol products contained 1 or 2 molecules of n-3 PUFA. With EEPA as the acyl
donor, the total EPA product yields with IM60 and SP435 as biocatalysts were 79.6 and 81.4%, respectively. However, with EDHA
as the acyl donor and IM60 and SP435 as biocatalysts, the total DHA product yields were 70.5 and 79.7%, respectively. Effects
of reaction parameters, such as type of solvent, enzyme load, time course, and molar ratio of substrates on the n-3 PUFA incorporation,
were followed with SP435 as the biocatalyst. High yields were obtained, even in the absence of organic solvent. These lipids
do hold promise for specialty nutrition and other therapeutic uses. 相似文献
18.
Michel Bédard Shawn Marshall Malcolm Man-Son-Hing Bruce Weaver Isabelle Gélinas Nicol Korner-Bitensky Barbara Mazer Gary Naglie Michelle M. Porter Mark J. Rapoport Holly Tuokko Brenda Vrkljan 《Accident; analysis and prevention》2013
Background
A new tool, the SIMARD-MD, has been proposed to help physicians identify cognitively impaired drivers who may be unfit to drive, but little empirical evidence is available to justify its use. We analyzed data from a cohort of older Canadian drivers who had undergone cognitive testing to: (1) correlate the SIMARD-MD with other tools that measure cognition (e.g., trail-making test), (2) identify how many drivers, using published cut-offs on the SIMARD-MD, would be recommended to lose their license, or be considered fit to drive, or be required to undergo further driving assessment, and (3) determine if the SIMARD-MD is biased by level of education as many cognitive tools are.Methods
Cross-sectional data from 841 drivers aged 70 and over from seven Canadian sites who are enrolled in a 5-year cohort study were used for the analyses. Scores on the SIMARD-MD were correlated with scores on the other cognitive measures. The recommendations that would be made based on the SIMARD-MD scores were based on published cut-off values suggested by the authors of the tool. The impact of education status was examined using linear regression controlling for age.Results
Correlations between the SIMARD-MD and other cognitive measures ranged from .15 to .86. Using published cut-off scores, 21 participants (2.5%) would have been recommended to relinquish their licenses, 428 (50.9%) would have been deemed fit to drive, and 392 (46.6%) would have been required to undergo further testing. We found a difference of 8.19 points (95% CI = 4.99, 11.40, p < .001) in favor of drivers with post-secondary education versus those without, representing over 11% of the mean score.Discussion
The SIMARD-MD is unlikely to be valuable to clinicians because it lacks sufficient precision to provide clear recommendations about fitness-to-drive. Recommendations based solely on the SIMARD-MD may place many seniors at risk of losing their transportation mobility or incurring unnecessary stress and costs to prove they are safe to drive. Furthermore, the education bias may create an unwanted structural inequity. Hence, adoption of the SIMARD-MD as a tool to determine fitness-to-drive appears premature. 相似文献19.
Andrew Woolnough Danish Salim Shawn C. Marshall Kelly Weegar Michelle M. Porter Mark J. Rapoport Malcolm Man-Son-Hing Michel Bédard Isabelle Gélinas Nicol Korner-Bitensky Barbara Mazer Gary Naglie Holly Tuokko Brenda Vrkljan 《Accident; analysis and prevention》2013
Background
Chronic health conditions associated with ageing can lead to changes in driving ability. The Canadian Driving Research Initiative for Vehicular Safety in the Elderly (Candrive II) is a 5-year prospective study funded by the Canadian Institutes of Health Research aiming to develop an in-office screening tool that will help clinicians identify potentially at-risk older drivers. Currently, no tools exist to directly predict the risk of motor vehicle collision (MVC) in this population. The American Medical Association (AMA), in collaboration with the National Highway Traffic Safety Association, has designed an opinion-based guide for assessing medical fitness to drive in older adults and recommends that physicians use the Assessment of Driving Related Skills (ADReS) as a test battery to measure vision, cognition and motor/somatosensory functions related to driving. The ADReS consists of the Snellen visual acuity test, visual fields by confrontation test, Trail Making Test part B, clock drawing test, Rapid Pace Walk, and manual tests of range of motion and motor strength. We used baseline data from the Candrive/Ozcandrive common cohort of older drivers to evaluate the validity of the ADReS subtests. We hypothesized that participants who crashed in the 2 years before the baseline assessment would have poorer scores on the ADReS subtests than participants who had not crashed.Methods
In the Candrive/Ozcandrive study, 1230 participants aged 70 years or older were recruited from 7 Canadian cities, 1 Australian city and 1 New Zealand city, all of whom completed a comprehensive clinical assessment at study entry. The assessment included all tests selected as part of the ADReS. For this historical cohort study, data on all crashes (at-fault and non-at-fault) that occurred within 2 years preceding the baseline assessment were obtained from the respective licensing jurisdictions. Those who crashed were compared to those who had not crashed on their ADReS subtest scores using Pearson's chi-squared test and Student's t-test.Results
Sixty-three of the 1230 participants (5.1%) were involved in an MVC within the 2 years preceding the baseline assessment. Contrary to our hypothesis, there were no statistically significant associations between abnormal performance on the tests constituting the ADReS and history of crash in the previous 2 years (p > 0.01).Discussion
We found that a history of crash in the previous 2 years was not associated with abnormalities on the subtests comprising the ADReS. This suggests the need for prospective analyses of risk factors over time to establish sensitive, valid predictors of crash that can be incorporated in clinical practice guidelines. 相似文献20.
Prof. Alain Verbeke Ph.D. Assoc. Prof. Vernon Bachor Ph.D. Brenda Nguyen 《Management International Review》2013,53(4):535-554
- This paper empirically tests the effectiveness of information and communications technology (ICT) knowledge transfer and adoption in the multinational enterprise (MNE) as an issue of critical importance to contemporary MNE functioning. In contrast to mainstream thinking on absorptive capacity, but in line with prevailing international business theory, our research supports the proposition that perceptions of procedural justice, rather than absorptive capacity, determine effectiveness, especially in cases of high tacit knowledge transfers.
- Data was collected from senior ICT representatives in 86 Canadian subsidiaries of foreign owned MNEs. Each of these subsidiaries recently experienced a significant ICT transfer imposed by the parent organization.
- Support was found for the main propositions: Procedural justice significantly predicted successful ICT transfer and adoption, while absorptive capacity was not significant. These findings are consistent even when knowledge tacitness was high.
- The perceived success of the ICT transfer as well as its adoption varied widely across these firms. The potential reasons for this divergence in effectiveness are manifold, but our findings suggest that in situations of substantial knowledge tacitness, a higher level of procedural justice, rather than a higher level of absorptive capacity, is critical to effective transfer and adoption.