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61.
创新无止境,现代针灸学的科学研究不应当受制于古人总结的概念、学说.将传统的概念范畴作为实证研究的对象是犯了先入为主的错误.中医针灸需要人文滋养,但人文滋养无法取代科学的支撑.以传统概念体系指导现代针灸学的科学研究是事前为自己设置的桎梏,这类课题立项时就决定了其结果的悲壮命运.  相似文献   
62.
临床证据发现空间忽视症病人对于近处和远处空间内的注意加工存在差异,表现为空间忽视只发生于近处空间或只发生于远处空间,提示近处空间与远处空间在脑内可能是分别表征的。对健康成人的研究也发现了与之类似的近处空间和远处空间注意的分离现象,即在近处空间表现出左偏的伪忽视现象,在远处空间表现出左偏减弱或者右偏的趋势。本文综述了远、近空间内注意加工分离的实验证据以及采用线段二分任务这一主要的研究范式相关的实验结果,并且着重指出了远、近空间的划分不是绝对的,而是动态可变的研究证据。最后,指出了将来的研究需要深入考察空间参照系统在远、近空间知觉中的作用,以及关注社会交互情境下的远、近空间距离认知的动态变化。  相似文献   
63.
We used 18F-fluorodeoxyglucose small-animal positron-emission tomography to determine whether different styles of coping with stress are associated with different patterns of neuronal activity in the hypothalamus. Adult rats were subjected to immobilization (IMO)-stress or to a non-immobilized condition for 30 min, in random order on separate days, each of which was followed by brain-scanning. Some rats in the immobilized condition were allowed to actively cope with the stress by chewing a wooden stick during IMO, while the other immobilized rats were given nothing to chew on. Voxel-based statistical analysis of the brain imaging data shows that chewing counteracted the stress-induced increased glucose uptake in the hypothalamus to the level of the non-immobilized condition. Region-of-interest analysis of the glucose uptake values further showed that chewing significantly suppressed stress-induced increased glucose uptake in the paraventricular hypothalamic nucleus and the anterior hypothalamic area but not in the lateral hypothalamus. Together with the finding that the mean plasma corticosterone concentration at the termination of the IMO was also significantly suppressed when rats had an opportunity to chew a wooden stick, our results showed that active coping by chewing inhibited the activation of the hypothalamic-pituitary-adrenal axis to reduce the endocrine stress response.  相似文献   
64.
Pastoral Psychology - This paper highlights the integration of spiritual and religious approaches in psychotherapy using the three major religions (Taoism, Buddhism, and Christianity) of the...  相似文献   
65.
Tripping and falling is a serious health problem for older citizens due to the high medical costs incurred and the high mortality rates precipitated mostly by hip fractures that do not heal well. Current falls prevention technology encompasses a broad range of interventions; both passive (e.g., safer environments, hip protectors) and active (e.g., sensor-based fall detectors) which attempt to reduce the effects of tripping and falling. However the majority of these interventions minimizes the impact of falls and do not directly reduce the risk of falling. This paper investigates the prediction of gait parameters related to foot-to-ground clearance height during the leg swing phase which have been physically associated with tripping and falling risk in the elderly. The objective is to predict parameters of foot trajectory several walking cycles in advance so that anticipated low foot clearance could be addressed early with more volitional countermeasures, e.g., slowing down or stopping. In this primer study, foot kinematics was recorded with a highly accurate motion capture system for 10 healthy adults (25-32 years) and 11 older adults (65-82 years) with a history of falls who each performed treadmill walking for at least 10 min. Vertical foot displacement during the swing phase has three characteristic inflection points and we used these peak values and their normalized time as the target prediction values. These target variables were paired with features extracted from the corresponding foot acceleration signal (obtained through double differentiation). A generalized regression neural network (GRNN) was used to independently predict the gait variables over a prediction horizon (number of gait cycles ahead) of 1-10 gait cycles. It was found that the GRNN attained 0.32-1.10 cm prediction errors in the peak variables and 2-8% errors in the prediction of normalized peak times, with slightly better accuracies in the healthy group compared to elderly fallers. Prediction accuracy decreased linearly (best fit) at a slow rate with increasing prediction horizon ranging from 0.03 to 0.11 cm per step for peak displacement variables and 0.34 × 10(-3) - 1.81 × 10(-3)% per step for normalized peak time variables. Further time series analysis of the target gait variable revealed high autocorrelations in the faller group indicating the presence of cyclic patterns in elderly walking strategies compared to almost random walking patterns in the healthy group. The results are promising because the technique can be extended to portable sensor-based devices which measure foot accelerations to predict the onset of risky foot clearance, thus leading to a more effective falls prevention technology.  相似文献   
66.
Contrasts of means are often of interest because they describe the effect size among multiple treatments. High-quality inference of population effect sizes can be achieved through narrow confidence intervals (CIs). Given the close relation between CI width and sample size, we propose two methods to plan the sample size for an ANCOVA or ANOVA study, so that a sufficiently narrow CI for the population (standardized or unstandardized) contrast of interest will be obtained. The standard method plans the sample size so that the expected CI width is sufficiently small. Since CI width is a random variable, the expected width being sufficiently small does not guarantee that the width obtained in a particular study will be sufficiently small. An extended procedure ensures with some specified, high degree of assurance (e.g., 90% of the time) that the CI observed in a particular study will be sufficiently narrow. We also discuss the rationale and usefulness of two different ways to standardize an ANCOVA contrast, and compare three types of standardized contrast in the ANCOVA/ANOVA context. All of the methods we propose have been implemented in the freely available MBESS package in R so that they can be easily applied by researchers.  相似文献   
67.
Language for number is an important case study of the relationship between language and cognition because the mechanisms of non-verbal numerical cognition are well-understood. When the Pirahã (an Amazonian hunter-gatherer tribe who have no exact number words) are tested in non-verbal numerical tasks, they are able to perform one-to-one matching tasks but make errors in more difficult tasks. Their pattern of errors suggests that they are using analog magnitude estimation, an evolutionarily- and developmentally-conserved mechanism for estimating quantities. Here we show that English-speaking participants rely on the same mechanisms when verbal number representations are unavailable due to verbal interference. Followup experiments demonstrate that the effects of verbal interference are primarily manifest during encoding of quantity information, and—using a new procedure for matching difficulty of interference tasks for individual participants—that the effects are restricted to verbal interference. These results are consistent with the hypothesis that number words are used online to encode, store, and manipulate numerical information. This linguistic strategy complements, rather than altering or replacing, non-verbal representations.  相似文献   
68.
This study examined the effects of visual-verbalload (as measured by a visually presented reading-memory task with three levels) on a visual/auditory stimulus-response task. The three levels of load were defined as follows: "No Load" meant no other stimuli were presented concurrently; "Free Load" meant that a letter (A, B, C, or D) appeared at the same time as the visual or auditory stimulus; and "Force Load" was the same as "Free Load," but the participants were also instructed to count how many times the letter A appeared. The stimulus-response task also had three levels: "irrelevant," "compatible," and "incompatible" spatial conditions. These required different key-pressing responses. The visual stimulus was a red ball presented either to the left or to the right of the display screen, and the auditory stimulus was a tone delivered from a position similar to that of the visual stimulus. Participants also processed an irrelevant stimulus. The results indicated that participants perceived auditory stimuli earlier than visual stimuli and reacted faster under stimulus-response compatible conditions. These results held even under a high visual-verbal load. These findings suggest the following guidelines for systems used in driving: an auditory source, appropriately compatible signal and manual-response positions, and a visually simplified background.  相似文献   
69.
为了考查情绪Stroop效应的产生机制是威胁驱动还是反应偏差,本研究进行了两个实验.实验一用一般负性情绪词语和中性词语作为实验材料,实验二用威胁性的情绪图片和中性图片作为实验材料.每个实验均要求一组被试做按键反应,另一组被试做摇杆反应.结果发现,当实验材料为词语时,未出现情绪Stroop效应;当实验材料为威胁性图片时,无论是趋向性反应方式还是回避性反应方式,都出现了情绪Stroop效应.本研究结果支持威胁驱动机制.  相似文献   
70.
采用累积生态风险问卷、消极自我图式问卷、网络成瘾问卷以及学习倦怠问卷对湖南省4所高职院校的664名高职生进行调查,考察累积生态风险与高职生学习倦怠的关系以及消极自我图式、网络成瘾的中介作用。结果发现:(1)高职生累积生态风险、消极自我图式、网络成瘾和学习倦怠均呈显著正相关;(2)高职生累积生态风险对学习倦怠的直接效应和间接效应均显著。间接效应包括了三条路径:通过消极自我图式的中介作用、通过网络成瘾的中介作用以及通过消极自我图式和网络成瘾的链式中介作用。这一结论有助于理解累积生态风险对学习倦怠的作用机制,为降低高职生的学习倦怠提供参考建议。  相似文献   
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