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861.
Background: Increasing numbers of HIV‐infected gay men acquire hepatitis C virus (HCV) co‐infection, which causes serious medical consequences. Treatment for HCV is associated with many severe side effects, in some cases psychological, and many patients subsequently fail to adhere, even when psychological services are utilised, to improve treatment adherence. Objective: This qualitative study aimed to explore the experiences of HIV‐infected gay men undergoing treatment for HCV in order to inform psychological services to better meet specific treatment needs of this population. Methods: Thirteen HIV‐infected gay men who had undergone HCV treatment were interviewed and a qualitative analysis was conducted. Participants described HCV and its treatments in the context of their relationships and lifestyles. Findings: Four domains emerged: HCV diagnosis and treatment; HCV treatment education; change in sense of self; and sexual risk‐taking. Adhering to treatment was a significant challenge for all participants and emerged across all domains. Discussion: Psychological services for this population of co‐infected gay men should assist this clinical population not only with adherence to hepatitis C treatment but should also be available at an earlier stage in the process to help patients make informed choices about whether or not to begin a course of treatment. Assessing factors such as coping strategies, treatment readiness and knowledge, self‐awareness, and level of risk‐taking, can guide clinicians in tailoring treatment and adherence planning for HIV/HCV‐co‐infected gay men.  相似文献   
862.
青少年网络成瘾研究进展   总被引:1,自引:0,他引:1  
青少年网络成瘾是信息时代的一种阻碍青少年健康成长的问题。本文对青少年网络成瘾的测量、影响因素及其干预等问题进行综述,并对未来研究方向提出建议,为以后研究提供借鉴。  相似文献   
863.
While research on the spatial representation of number has provided substantial evidence for a horizontally oriented mental number line, recent studies suggest vertical organization as well. Directly comparing the relative strength of horizontal and vertical organization, however, we found no evidence of spontaneous vertical orientation (upward or downward), and horizontal trumped vertical when pitted against each other (Experiment 1). Only when numbers were conceptualized as magnitudes (as opposed to nonmagnitude ordinal sequences) did reliable vertical organization emerge, with upward orientation preferred (Experiment 2). Altogether, these findings suggest that horizontal representations predominate, and that vertical representations, when elicited, may be relatively inflexible. Implications for spatial organization beyond number, and its ontogenetic basis, are discussed.  相似文献   
864.
Metamemory processes and executive control may be related, given that both are frontally mediated. However, previous behavioural research has been limited in identifying common processes driving this somewhat weak relationship partly because they mostly relied upon global executive measures and composite scores of executive function (EF). The present study investigated the relationship between specific EFs (task shifting, interference resolution), working memory capacity and feeling-of-knowing (FOK) and confidence judgements (CONF) in an episodic memory task. We found that, of the EFs, only task-switching performance was correlated with FOK accuracy and proposed a shared mechanism that may be at play in both task-switching and FOK judgements. We also demonstrated that interference resolution and episodic memory measures were related, suggesting strategic influences on memory retrieval. Finally, we found a strong consistency in the strength and accuracy of FOK and CONF judgements, possibly due to retrieval-based mechanisms in both types of judgements.  相似文献   
865.
866.
Panel pressing was generated and maintained in 5 adult humans by schedules of points exchangeable for money. Following exposure to a variable-interval 30-s schedule and to a linear variable-interval 30-s schedule (which permitted points to accumulate in an unseen "store" in the absence of responding), subjects were exposed to a series of conditions with a point-subtraction contingency arranged conjointly with the linear variable-interval schedule. Specifically, points were added to the store according to the linear-variable interval 30-s schedule and were subtracted from the store according to a ratio schedule. Ratio value varied across conditions and was determined individually for each subject such that the subtraction contingency would result in an approximately 50% reduction in the rate of point delivery. Conditions that included the subtraction contingency were termed negative slope schedules because the feedback functions were negatively sloped across all response rates greater than the inverse of the variable-interval schedule, in this case, two per minute. Overall response rates varied inversely with the subtraction ratio, indicating sensitivity to the negative slope conditions, but were in excess of that required by accounts based on strict maximization of overall reinforcement rate. Performance was also not well described by a matching-based account. Detailed analyses of response patterning revealed a consistent two-state pattern in which bursts of high-rate responding alternated with periods of prolonged pausing, perhaps reflecting the joint influence of local and overall reinforcement rates.  相似文献   
867.
A commutative BCK-algebra with the relative cancellation property is a commutative BCK-algebra (X;*,0) which satisfies the condition: if ax, ay and x * a = y * a, then x = y. Such BCK-algebras form a variety, and the category of these BCK-algebras is categorically equivalent to the category of Abelian ℓ-groups whose objects are pairs (G, G 0), where G is an Abelian ℓ-group, G 0 is a subset of the positive cone generating G + such that if u, vG 0, then 0 ∨ (u - v) ∈ G 0, and morphisms are ℓ-group homomorphisms h: (G, G 0) → (G′,G0) with f(G 0) ⫅ G0. Our methods in particular cases give known categorical equivalences of Cornish for conical BCK-algebras and of Mundici for bounded commutative BCK-algebras (= MV-algebras). This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
868.
Recently, Finch et al. (Journal of Personality, 1999) reported the results of a meta-analysis in which social negativity was demonstrated to be positively related to psychological distress. In the present investigation, we employed meta-analytic techniques to test competing hypotheses as to whether age amplifies or dampens the relation of social negativity and psychological distress. A total of 104 effect sizes (e.g., concurrent correlations between self-report measures of social negativity and psychological distress) from 53 independent samples were extracted from 46 journal articles. Contrary to hypotheses, the relation between social negativity and psychological distress was not significantly different for samples of older (60 + years) and younger (<60 years) adults. An explanation was provided for why the present meta-analysis and previous narrative reviews have resulted in discrepant conclusions about negativity effects.  相似文献   
869.
The increased risk of falls in the older aged population demands the development of assistive robotic devices capable of effective balance support. For the development and increased user acceptance of such devices, which provide balance support in a human-like way, it is important to understand the simultaneous occurrence of entrainment and sway reduction in human-human interaction. However, sway reduction has not been observed yet during a human touching an external, continuously moving reference, which rather increased human body sway. Therefore, we investigated in 15 healthy young adults (27.20±3.55 years, 6 females) how different simulated sway-responsive interaction partners with different coupling modes affect sway entrainment, sway reduction and relative interpersonal coordination, as well as how these human behaviours differ depending on the individual body schema accuracy. For this, participants were lightly touching a haptic device that either played back an average pre-recorded sway trajectory (“Playback”) or moved based on the sway trajectory simulated by a single-inverted pendulum model with either a positive (Attractor) or negative (Repulsor) coupling to participant's body sway. We found that body sway reduced not only during the Repulsor-interaction, but also during the Playback-interaction. These interactions also showed a relative interpersonal coordination tending more towards an anti-phase relationship, especially the Repulsor. Moreover, the Repulsor led to the strongest sway entrainment. Finally, a better body schema contributed to a reduced body sway in both the “reliable” Repulsor and the “less reliable” Attractor mode. Consequently, a relative interpersonal coordination tending more towards an anti-phase relationship and an accurate body schema are important to facilitate sway reduction.  相似文献   
870.
Stimulus identification and action outcome understanding for a rapid and accurate response selection, play a fundamental role in racquet sports. Here, we investigated the neurodynamics of visual anticipation in tennis manipulating the postural and kinematic information associated with the body of opponents by means of a spatial occlusion protocol. Event Related Potentials (ERPs) were evaluated in two groups of professional tennis players (N = 37) with different levels of expertise, while they observed pictures of opponents and predicted the landing position as fast and accurately as possible. The observed action was manipulated by deleting different body districts of the opponent (legs, ball, racket and arm, trunk). Full body image (no occlusion) was used as control condition. The worst accuracy and the slowest response time were observed in the occlusion of trunk and ball. The former was associated with a reduced amplitude of the ERP components likely linked to body processing (the N1 in the right hemisphere) and visual-motor integration awareness (the pP1), as well as with an increase of the late frontal negativity (the pN2), possibly reflecting an effort by the insula to recover and/or complete the most correct sensory-motor representation. In both occlusions, a decrease in the pP2 may reflect an impairment of decisional processes upon action execution following sensory evidence accumulation. Enhanced amplitude of the P3 and the pN2 components were found in more experienced players, suggesting a greater allocation of resources in the process connecting sensory encoding and response execution, and sensory-motor representation.  相似文献   
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