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91.
92.
分析比较切开复位内固定和人工桡骨小头置换方法治疗桡骨小头粉碎性骨折(MasonⅢ型)的临床疗效。回顾分析2012年10月~2014年3月收治的24例桡骨小头粉碎性骨折(MasonⅢ型)的临床资料,其中切开复位内固定治疗17例;桡骨小头置换7例,平均随访12个月(6个月~18个月)。根据Broberg Morrey评分系统以及术后影像进行评价比较,同时比较两组住院天数以及费用。结果评价比较显示两者疗效均佳,术后两者活动度和功能评分相近,两组住院天数相近,内固定组费用更低。桡骨小头粉碎性骨折须尽早进行解剖复住功能重建,切开复位内固定和桡骨小头置换疗效相当。 相似文献
93.
Updating working memory in aircraft noise and speech noise causes different fMRI activations 下载免费PDF全文
The present study used fMRI/BOLD neuroimaging to investigate how visual‐verbal working memory is updated when exposed to three different background‐noise conditions: speech noise, aircraft noise and silence. The number‐updating task that was used can distinguish between “substitution processes,” which involve adding new items to the working memory representation and suppressing old items, and “exclusion processes,” which involve rejecting new items and maintaining an intact memory set. The current findings supported the findings of a previous study by showing that substitution activated the dorsolateral prefrontal cortex, the posterior medial frontal cortex and the parietal lobes, whereas exclusion activated the anterior medial frontal cortex. Moreover, the prefrontal cortex was activated more by substitution processes when exposed to background speech than when exposed to aircraft noise. These results indicate that (a) the prefrontal cortex plays a special role when task‐irrelevant materials should be denied access to working memory and (b) that, when compensating for different types of noise, either different cognitive mechanisms are involved or those cognitive mechanisms that are involved are involved to different degrees. 相似文献
94.
Continuous white noise played through headphones was used as a classroom intervention to reduce off-task behavior and increase assignment production and accuracy for a child with Attention Deficit Hyperactivity Disorder (ADHD). When listening to white noise the student's off-task behavior decreased from 89% during baseline to 62%. Subsequently, he began taking a stimulant medication for his ADHD. Pharmacotherapy alone (65% off task) was approximately equivalent to white noise alone. When medication was combined with white noise his off-task behavior decreased to 45%. Assignment production was also enhanced while listening to white noise, whereas accuracy remained high throughout. 相似文献
95.
Shelby J. Haberman Lili Yao Sandip Sinharay 《The British journal of mathematical and statistical psychology》2015,68(2):363-385
In many educational tests which involve constructed responses, a traditional test score is obtained by adding together item scores obtained through holistic scoring by trained human raters. For example, this practice was used until 2008 in the case of GRE®General Analytical Writing and until 2009 in the case of TOEFL® iBT Writing. With use of natural language processing, it is possible to obtain additional information concerning item responses from computer programs such as e‐rater®. In addition, available information relevant to examinee performance may include scores on related tests. We suggest application of standard results from classical test theory to the available data to obtain best linear predictors of true traditional test scores. In performing such analysis, we require estimation of variances and covariances of measurement errors, a task which can be quite difficult in the case of tests with limited numbers of items and with multiple measurements per item. As a consequence, a new estimation method is suggested based on samples of examinees who have taken an assessment more than once. Such samples are typically not random samples of the general population of examinees, so that we apply statistical adjustment methods to obtain the needed estimated variances and covariances of measurement errors. To examine practical implications of the suggested methods of analysis, applications are made to GRE General Analytical Writing and TOEFL iBT Writing. Results obtained indicate that substantial improvements are possible both in terms of reliability of scoring and in terms of assessment reliability. 相似文献
96.
Most older adults will eventually stop driving, but few engage in planning for driving retirement. This study assessed whether driving stress, enjoyment, confidence, concerning driving events, and assessment of driving alternatives influence planning. Demographic factors were also included. Data were collected via a mailed transportation survey, with a final sample of 551 older adults who currently drive. Linear regression analyses revealed that more driving retirement planning was associated with greater driving stress, less driving confidence, and a more positive view of driving alternatives. Driving enjoyment and recent concerning driving events were not significantly related. Among the control variables, race and income were significantly related to planning, suggesting that lower income and identifying as Black race were associated with more planning. Gender only approached significance, suggesting that females may plan more than males. Overall, these findings suggest that more driving retirement planning is warranted. Some of the groups known to be at increased risk for driving reduction and cessation plan more for that eventuality than their counterparts. Implications of the study and suggestions for future research are discussed. 相似文献
97.
Dedicated road markings for motorcyclists were installed on the approach to demanding bends at 10 sites across the West Highlands of Scotland. These road markings were designed as Perceptual Rider Information for Maximising Expertise and Enjoyment (PRIMEs) which presented a series of ‘gateway’ markings to encourage safer riding. Video data were collected to measure motorcycle speed, position, braking and use of the road markings, before and after the PRIMEs were installed. A total of 12,949 motorcyclists were observed. Speed reductions were observed across four of the 10 sites, changes in lateral position at the final PRIME gateway marking and apex of the bend were observed across all 10 sites and seven sites respectively; reduced braking was observed at two sites and there was an increase in the use of PRIME road markings across eight of the 10 sites. These findings are discussed in relation to the ‘Safe System’ approach to improving motorcycle safety. 相似文献
98.
Problem: Evolving sandstorms on rural expressways in desert countries impair drivers' contrast vision and increase the risk of serious crashes due to delayed speed adjustments. Intelligent Transport Systems (ITS) such as Variable Message Signs (VMS) conveying warnings can be activated to address drivers’ speed adaptation before entering a low visibility zone. To improve drivers’ understanding of the hazard, a sandstorm animation visualizing turbulent sand and its consequences was designed and compared with a general warning pictogram, which is applied if no specific weather pictogram is available. Moreover, minimum warning distances of the VMS to the low visibility zone were tested (e.g., 300 m or 500 m).MethodSixty-three participants from the State of Qatar drove in a driving simulator through clear, transition, and low visibility conditions on a rural expressway. A repeated analysis of variances was conducted to examine the impact of the two on-road warning displays on driving behavior.ResultsThe results showed that the sandstorm animation was similarly effective as a generic warning pictogram in reducing driving speeds before entering the transition and low visibility zone, irrespective of being displayed 500 m or 300 m away. However, the sandstorm animation resulted in consistent similar speed reductions within the low visibility zone, whereas the generic warning pictogram did either perform better or worse after several encounters with a sandstorm. Drivers did strongly agree that the animation is clearly referring to the issue of low visibility, which can be beneficial for recurring low visibility conditions.Practical applications: 1.) Displaying a sandstorm animation is beneficial for rural expressway sections with recurring degrading visibility and low traffic densities, whereas a warning pictogram can be more effective in speed reductions if drivers expect additional traffic hazards. 2.) Roadway authorities have the flexibility to activate a VMS sandstorm warning even for minimum warning distances. 相似文献
99.
Misophonia refers to one's sensitivity to specific sounds, which can range from minor annoyance to extreme distress. This experiment tested the role of individual differences in misophonia sensitivity on learning. College students read a text passage about migraines in a quiet room with 2 or 3 other participants and 1 confederate. In some sessions, the confederate audibly chewed gum while reading the text (sound group); in other sessions, the confederate read silently (control group). All participants then completed a comprehension test on the material, followed by an assessment of their misophonia sensitivity. Although there was no overall difference between the two groups on the comprehension test, misophonia sensitivity significantly moderated the effect of the trigger sound on learning. Students who scored relatively high on misophonia sensitivity performed worse on the comprehension test if they were in the sound group but performed better if they were in the control group. 相似文献
100.
整体运动知觉存在年龄相关的衰退,然其老化的视觉机制仍不清楚。本研究分别招募34名青年人和老年人为研究对象,采用随机点阵范式,首次以动态速度为外部噪声考察了这一问题。结果发现,老年组整体运动一致性阈值显著高于青年组,且中等速度下的差异较小,证明整体运动知觉存在老化效应,且老化程度受到速度的影响。对两组数据进行知觉模板拟合发现,以青年组为基准,老年组表征内部加法噪声和排除外部噪声能力的 Aa 和 Af 均大于1,且 Aa >> Af ,提示老年人整体运动知觉的衰退可能源于其内部加法噪声的增强和排除外部噪声能力的减弱,其中内部加法噪声的增强更为显著。 相似文献