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131.
Infants show age-related improvements in reach straightness and smoothness over the first years of life as well as a decrease in average movement speed. This period of changing kinematics overlaps the emergence of handedness. We examined whether infant hand preference status is related to the development of motor control in 53 infants ranging from 11 to 14 months old. Hand preference status was assessed from reaching to a set of 5 objects presented individually at the infant's midline; infants were classified into ‘right preference’ or ‘no preference’ groups. Three-dimensional (3-D) recordings were made of each arm for reaches under two distinct conditions: pick up a ball and fit it into the opening of a toy (grasp-to-place task) or pick up a Cheerio® and consume it (grasp-to-eat task). Contrary to expectations, there was no effect of hand preference status on reach smoothness or straightness for either task. On the grasp-to-eat task only, average speed of the left hand differed as a function of hand preference status. Infants in the no preference group exhibited higher left hand average speeds than infants in the right preference group. Our results suggest that while behavioral differences in the use of the two hands may be present in some infants, these differences do not appear to be systematically linked to biases in motor control of the arms early in development.  相似文献   
132.
根据血压昼夜节律,观察给药时间对血压晨峰的影响。256例原发性高血压患者,经24h动态血压监测分为超杓型(n=49)、杓型(n=127)和非杓型(n=80)3组;各组再分为清晨服药组和晚上服药组。用药6周,比较用药前后血压昼夜节律及血压晨峰的变化,发现在改变血压昼夜节律及降低血压晨峰方面,超杓型组清晨服药优于晚上服药,非杓型组晚上服药优于清晨服药;杓型组清晨服药与晚上服药均能降低晨峰值,提示根据个体血压昼夜节律选择服药时间能更好地控制血压晨峰。  相似文献   
133.
Consumers often share word of mouth, and such interpersonal communication shapes attitudes and purchases. But while some research has examined what consumers talk about, there has been less attention to when consumers discuss. How does the distance from now (i.e., whether something is temporally near or far away) shape the likelihood of discussion? And might the effect of temporal distance on word of mouth vary based on whether those things happened in the past or will happen in the future? Five studies, including analyses of thousands of social media posts, address these questions. They suggest that consumers tend to talk about temporally near things, but that this is moderated by whether they are talking about the past or future (i.e., consumers talk about more temporally distant things when talking about the future). Accessibility seems to play an important role in these effects. While temporally near things tend to be more accessible, on average, goals and plans are more likely to remain active in the future, which shapes what gets discussed. These findings have implications for understanding drivers of word of mouth, how time shapes consumer behavior, and how companies can more effectively manage interpersonal communication.  相似文献   
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135.
Five pigeons were given single-stimulus training on an 8-sec differential-reinforcement-of-low-rate schedule followed by steady-state generalization training using 12 wavelength stimuli. Three birds had a high percentage of reinforced responses on the training schedule and flat generalization gradients of total responses. The birds with fewer reinforced responses had much steeper generalization gradients. Generalization gradients plotted as a function of both stimulus wavelength and interresponse time showed that for most birds, stimulus control was restricted to responses with long interresponse times. Responses with very short interresponse times were not under stimulus control and there was some evidence of inhibitory control of short interresponse times. Interresponse-times-per-opportunity functions, plotted as a function of stimulus wavelength, showed that stimulus wavelength controlled the temporal distribution of responses, rather than the overall rate of response. The data indicate that the differential-reinforcement-of-low-rate schedule generates several response categories that are controlled in different ways by wavelength and time-correlated stimuli, and that averaging responses regardless of interresponse-time length obscures this control.  相似文献   
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137.
Free-floating bike sharing (FFBS) provides citizens with a flexible way for traveling. The operational performance of such systems is impacted by the imbalance problem of demand and supply. This paper proposes the first two-stage incentive mechanism to improve the service quality of FFBS. While inspired by the user-based rebalancing approach in station-based bike sharing (SBBS), our work is different from existing studies because location optimization is a new problem in FFBS and user preference is considered for the first time. We propose three mechanisms that are pick-up incentives, drop-off incentives, and two-stage incentives. When modeling users’ behavioral responses to incentive mechanisms, we think users prefer drop-off incentives to pick-up incentives, which is supported by a survey study. Each incentive offer is composed of a location and a price. To decide the suggested origin or destination, we first figure out the supply and demand of all valid locations based on Radiant Service Theory (RST) and then search the most problematic location comparing current inventory and future demand. The pricing scheme is modified Budgeted Procurement using Upper Confidence Bounds (BP-UCB). Simulation experiments validate the effectiveness of incentive mechanisms based on historical data from Capital BikeShare program. Results show that the service level of bike sharing systems can be significantly improved by three incentive mechanisms. The two-stage incentive mechanism unexpectedly shows no advantage over pick-up incentives. Sensitivity analysis further indicates that user preference will influence the ranking of two single-stage incentive mechanisms.  相似文献   
138.
互联网内容偏好与大学生人格特质关系的研究   总被引:4,自引:1,他引:4  
李秀敏 《心理科学》2004,27(3):559-562
本研究对2034名在校大学生的上网情况和人格特质进行测试,探讨大学生网络内容偏好程度与接触频率的关系以及不同人格特质的大学生在互联网内容的偏好上是否有显著性差异。结果表明:(1)接触频率最高的是聊天内容,最低的是网上购物,男生显著高于女生的是游戏类内容,女生显著高于男生的是聊天类内容。(2)不同人格特质的大学生在内容偏好上存在显著差异。  相似文献   
139.
The human brain has a tendency to drift into the realm of internally-generated thoughts that are unbound by space and time. The term mind-wandering (MW) is often used describe such thoughts when they are perceptually decoupled. Evidence suggests that exposure to forward and backward illusory motion skews the temporal orientation of MW thoughts to either the future or past respectively. However, little is known about the impact of this manipulation on other features of MW. Here, using a novel experimental paradigm, we first confirmed that our illusory motion method facilitated the generation of MW thoughts congruent with the direction of motion. We then conducted content analyses which revealed that goal orientation and temporal distance were also significantly affected by the direction of illusory motion. We conclude that illusory motion may be an effective means of assaying MW and could help to elucidate this ubiquitous, and likely critical, component of cognition.  相似文献   
140.
It is widely assumed that reinforcers are biologically relevant stimuli, or stimuli that have been associated with biologically relevant stimuli. However, brief, arbitrary stimuli have also been reported to have reinforcement-like effects, despite being unrelated to biologically relevant stimuli like food. The present study explored the potential reinforcement-like effects of brief stimuli across 5 experiments. In Experiments 1 through 4, pigeon subjects responded for food reinforcement and brief stimulus presentations in a 2-component multiple schedule. Neither baseline response rates nor resistance to change during disruption tests were systematically greater in a component with versus without brief stimulus presentations. Increasing the rate and duration of brief stimulus presentations in Experiment 4 did not reveal reinforcement-like effects when compared directly with food. In Experiment 5, pigeons chose between independent terminal links in a concurrent-chains procedure. Across conditions, varying the location, duration, and rate of brief stimulus presentations in the terminal links had no systematic effects on preference. In contrast, varying rates of food reinforcers resulted in large and reliable shifts in preference. Therefore, the present study found no systematic evidence that brief stimuli unrelated to food reliably increase response rates, resistance to change, or preference. These data demonstrate the value of systematic replication, and a behavioral momentum approach to assessing potential reinforcement-like effects.  相似文献   
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