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71.
Dinsmoor's (2001) adherence to molecular analyses may require him to assert that molar and molecular principles are mutually exclusive, but to instead analyze the phenomena of avoidance as inherently multiscaled is to follow a well-established practice in the natural sciences. Besides the issue of scale, two-factor theory, which Dinsmoor advocates, has little to say about some important and longstanding results in experiments that qualify as avoidance.  相似文献   
72.
糖皮质激素是最有效的抗气道炎症药物,吸入糖皮质激素(ICS)是首选哮喘控制药物。由于治疗后达到哮喘临床控制(症状、肺功能)需要一定时间,ICS达到一定剂量后量效曲线较平坦,而全身不良反应却逐渐增加。因此,达到临床控制后在长期监测下至少维持哮喘控制3个月以上,开始减少50%ICS剂量,直至ICS减至最低维持剂量。如为ICS加另一种控制药(长效β2受体激动剂、白三烯调节剂、缓释茶碱)联合治疗达到控制者,在ICS减至最低剂量时再停用另一种控制药。应用最低剂量ICS维持控制达1年方可考虑停药。  相似文献   
73.
We report six unsuccessful attempts to replicate the "work ethic" phenomenon reported by Clement, Feltus, Kaiser, and Zentall (2000). In Experiments 1-5, pigeons learned two simultaneous discriminations in which the S+ and S- stimuli were obtained by pecking an initial stimulus once or multiple (20 or 40) times. Subsequent preference tests between the S+ stimuli and between the S- stimuli mostly revealed indifference, on average, between the S+ from the multiple-peck (high-effort) trials and the S+ from the one-peck (low-effort) trials, and likewise between the two respective Sstimuli. Using a slightly different procedure that permitted assessment of the relative aversiveness of low versus high effort, Experiment 6 again revealed a pattern of indifference despite showing that pigeons took considerably longer to begin pecking on high- than on low-effort trials. Our findings call into question the reliability of the original findings and the sufficiency of the hypothesized within-trial contrast mechanism to produce them.  相似文献   
74.
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   
75.
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   
76.
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   
77.
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   
78.
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   
79.
PurposeDetermine whether anti-speeding messages displayed on roadside variable message signage (VMS) influence drivers’ speed choice selections.MethodSpeed detection tubes were installed across a single carriageway 60 km/h limit road section at positions prior to, immediately after, and at a longer distance from VMS display of anti-speeding messages during study Week2. Bi-directional vehicle speed data were collected continuously during the week prior to VMS installation (Week1), throughout the week that the anti-speeding messages were displayed (Week2), and a post-display week (Week3).ResultsOf six separately measured locations, Week2 southbound mean speeds (facing signage) and percent of drivers/riders exceeding the signed speed limit were consistently below those recorded during Week1 for all time periods. Aggregated Week3 (post-VMS) southbound data for all time periods, showed consistent patterns for mean speed and percent of drivers exceeding the signed speed limit, being higher than in Week2 (VMS displayed) but lower than during Week1 (pre-VMS).DiscussionCompared with Week1, messages influenced aggregate driver speed selection during Week2, with a residual positive effect (slower speeds) in Week3. While all three messages had positive effects, differences occurred in relative effectiveness between daytime (school and non-school hours) and night-time periods. Separately disaggregated data revealed differential effects for the three messages.ConclusionsFindings demonstrated the value of implementing theoretically informed message content and provided evidence for the impact that roadside road safety messaging can have on driver speed selection.  相似文献   
80.
ABSTRACT

Body-machine interfaces establish a way to interact with a variety of devices, allowing their users to extend the limits of their performance. Recent advances in this field, ranging from computer interfaces to bionic limbs, have had important consequences for people with movement disorders. The authors provide an overview of the basic concepts underlying the body-machine interface with special emphasis on their use for rehabilitation and for operating assistive devices. They outline the steps involved in building such an interface and highlight the critical role of body-machine interfaces in addressing theoretical issues in motor control as well as their utility in movement rehabilitation.  相似文献   
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