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111.
The privacy of patients is jeopardised when medical records and data are spread or shared beyond the protected cloud of institutions. This is because breaches force them to the brink that they start abstaining from full disclosure of their condition. This type of condition has a negative effect on scientific research, patients and all stakeholders. A blockchain-based data sharing system is proposed to tackle this issue, which employs immutability and autonomy properties of the blockchain to sufficiently resolve challenges associated with access control and handle sensitive data. Our proposed system is supported by a Discrete Wavelet Transform to enhance the overall security, and a Genetic Algorithm technique to optimise the queuing optimization technique as well. Introducing this cryptographic key generator enhances the immunity and system access control, which allows verifying users securely in a fast way. This design allows further accountability since all users involved are already known and the blockchain records a log of their actions. Only when the users’ cryptographic keys and identities are confirmed, the system allows requesting data from the shared queuing requests. The achieved execution time per node, confirmation time per node and robust index for block number of 0.19 s, 0.17 s and 20 respectively that based on system evaluation illustrates that our system is robust, efficient, immune and scalable.  相似文献   
112.
张丽  蒋慧  赵立 《心理科学》2018,(2):337-343
本研究拟考察发展性计算障碍儿童的认知缺陷成因。实验1要求被试在三种形式(点/点,数/数,点/数)下进行数量比较,实验2仅将点集替换为汉字数字词。结果表明障碍组和正常组在数/数、点/数和汉字/汉字比较任务上的成绩存在显著差异,而在点/点和汉字/汉字比较上没有差异。据此推论,计算障碍儿童符号加工能力受到损伤,符号与非符号数量转换能力存在缺陷,但非符号加工能力和不同符号间数量转换没有缺陷,支持语义提取缺陷假设。  相似文献   
113.
采用事件相关电位,运用无启动的同一字判断(靶字延迟反应)范式,以大学生为被试探讨汉字刺激质量和频率是否具有交互作用。行为结果显示,刺激质量和频率在反应时上存在交互作用。脑电结果显示,重度模糊诱发了更大的N250和N400,且刺激质量和频率在N400上存在交互作用。结论是,汉字刺激质量和频率在反应时和N400上存在交互作用,表明在汉字识别中存在串级加工,支持IA模型。  相似文献   
114.
概念隐喻理论认为个体建立基于身体经验的具体概念和抽象概念之间的隐喻联结是人类特有的认知方式。不管是具体概念还是抽象概念,只要有具身隐喻联结的概念,其语义的理解便会受到具身启动效应的影响。大脑在加工动词或者含动词的句子时,不仅激活了语言中枢和运动皮层,且大脑随着个体是否执行与语义相应的动作、抽象概念的熟悉程度和其文本背景是否符合等因素而激活不同的神经回路。本文将对以上研究进行梳理与分析,旨在从具身隐喻的视角为身体动作影响语义加工的神经机制模型提供初步的思路。  相似文献   
115.
This paper describes a programme of research addressing an intriguing inconsistency in research findings about cognitive processes under a high need for cognitive closure (NFC). While early studies demonstrated that individuals who seek closure opt for closed-minded cognitive strategies, a growing body of research has identified a number of circumstances in which individuals who are high in NFC engage in effortful, open-minded information processing to an even greater extent than their low NFC counterparts. This has posed the challenge of delineating the circumstances under which people motivated to reduce uncertainty (i.e., attain closure) engage in effortful and open-minded cognition from those situations in which they rely on simplistic, low-effort strategies. This also calls for theoretical advancement in NFC theory. We discuss our proposed solution to this puzzle and the implications of this model for real-world social phenomena.  相似文献   
116.
Background and objectives: Developmental theorists posit that temperament contributes to preadolescent’s stress response styles. Findings from empirical studies, however, have yielded mixed results, thus indicating a need to consider moderators of this relation. Utilizing an analytic framework guided by resiliency theory [Zimmerman, M. A. (2013). Resiliency theory: A strengths-based approach to research and practice for adolescent health. Health Education &; Behavior, 40, 381–383], this study examined achievement goal orientation as a moderator of the relation between temperament and stress response styles.

Methods: 96 preadolescent–parent dyads (Mage?=?10.30 years, range?=?9–12 years) participated in the study. Preadolescents reported on their achievement goal orientation, coping and involuntary stress responses (ISRs) styles and a parent reported on children’s temperament.

Results: Multiple regressions revealed that effortful control positively predicted preadolescent’s predominant use of engagement coping and negatively predicted predominance of ISRs, but only for children with a predominant mastery goal orientation. For preadolescents with a predominant performance goal orientation, effortful control negatively predicted the predominant use of engagement coping and positively predicted predominance of ISRs. Negative affectivity and its interaction with goal orientation did not predict coping or ISR styles.

Conclusions: Findings suggest that a predominant mastery goal orientation may function as a promotive factor by enhancing the contribution of effortful control to engagement coping styles and buffering against unmanaged reactivity.  相似文献   
117.
Background and Objectives: Preferential attention to threat, emotional response inhibition, and attentional control each purportedly play a key role in anxiety disorders. Divergent psychometric properties among attention measures may produce differential detection of anxiety-related associations and treatment-related changes. However, no studies have directly compared the psychometric properties of these attention measures in the same sample.

Design: Eighty-five young adults (M?=?19.41 years, SD?=?1.47, 48 Females) completed a cognitive task battery and a subset of 60 participants (M?=?19.42 years, SD?=?1.48, 33 Females) completed the task battery again approximately two weeks later.

Method: To assess preferential attention to threat, emotional response inhibition, and attentional control, the cognitive task battery included a dot-probe task, emotion and gender Stroop tasks, and a flanker task. Tasks varied in how attention was directed and if emotional stimuli were included. Internal consistency and test-retest reliability were compared across measures.

Results: Within the same sample, internal consistency and reliability differed across attention measures. Explicit attention measures (emotional Stroop and flanker) exhibited stronger internal consistency and greater test-retest reliability compared to implicit measures (dot-probe and gender Stroop).

Conclusions: These results inform clinical research using attention measures to assess anxiety-related differences and treatment response.  相似文献   
118.
In Alzheimer's disease (AD), it is now well established that recollection is impaired from the beginning of the disease, whereas findings are less clear concerning familiarity. One of the most important mechanisms underlying familiarity is the sense of familiarity driven by processing fluency. In this study, we attempted to attenuate recognition memory deficits in AD by maximizing the salience of fluency cues in two conditions of a recognition memory task. In one condition, targets and foils have been created from the same pool of letters (Overlap condition). In a second condition, targets and foils have been derived from two separate pools of letters (No‐Overlap condition), promoting the use of letter‐driven visual and phonetic fluency. Targets and foils were low‐frequency words. The memory tasks were performed by 15 patients with AD and 16 healthy controls. Both groups improved their memory performance in the No‐Overlap condition compared to the Overlap condition. Patients with AD were able to use fluency cues during recognition memory as older adults did, but this did not allow to compensate for dysfunction of recognition memory processes.  相似文献   
119.
People with dissociative seizures (DS) report a range of difficulties in emotional functioning and exhibit altered responding to emotional facial expressions in experimental tasks. We extended this research by investigating subjective and autonomic reactivity (ratings of emotional valence, arousal and skin conductance responses [SCRs]) to general emotional images in 39 people with DS relative to 42 healthy control participants, whilst controlling for anxiety, depression, cognitive functioning and, where relevant, medication use. It was predicted that greater subjective negativity and arousal and increased SCRs in response to the affective pictures would be observed in the DS group. The DS group as a whole did not differ from controls in their subjective responses of valence and arousal. However, SCR amplitudes were greater in ‘autonomic responders’ with DS relative to ‘autonomic responders’ in the control group. A positive correlation was also observed between SCRs for highly arousing negative pictures and self‐reported ictal autonomic arousal, in DS ‘autonomic responders’. In the DS subgroup of autonomic ‘non‐responders’, differences in subjective responses were observed for some conditions, compared to control ‘non‐responders’. The findings indicate unaffected subjective responses to emotional images in people with DS overall. However, within the group of people with DS, there may be subgroups characterized by differences in emotional responding. One subgroup (i.e., ‘autonomic responders’) exhibit heightened autonomic responses but intact subjective emotional experience, whilst another subgroup (i.e., ‘autonomic non‐responders’) seem to experience greater subjective negativity and arousal for some emotional stimuli, despite less frequent autonomic reactions. The current results suggest that therapeutic interventions targeting awareness and regulation of physiological arousal and subjective emotional experience could be of value in some people with this disorder.  相似文献   
120.
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