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171.
The widespread development of comprehensive community initiatives that aim to improve community health is driven by the need to change the systems charged with delivering the services and creating the policies related to a variety of health outcomes. Georgia's Family Connection initiative is the nation's largest statewide network of community collaboratives for health, with collaboratives operating in 159 counties. Data on community context, collaborative processes, engagement in systems change, and changes in programs and activities implemented, gathered consistently at the collaborative level over 3 years, will be used to answer the following questions. How do community contexts and the structure and processes of collaboratives affect implementation of systems change? How do systems changes affect intermediate outcomes such as the type of programs offered in a community? Longitudinal change in systems change and program implementation is described and significant predictors of between‐collaborative variation in longitudinal change for each outcome are identified.  相似文献   
172.
In examining representations of cities, disease, and human biology, this paper reflects on what technologies reveal of the conditions to which they’re turned.
Ian HargravesEmail:
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173.
孟子认为,仁义价值等是人的本性。价值是人的标志。它具有首先性、主体性。诚是善良的人性本体的现实化。可是性善说显然无法自圆其说。这便是人性悖论。义内说表明,陈述同样具有主体性。主体对对象的把握方式是推恩。推恩是一种感应方式。被感应的对象,有时候被称为神。  相似文献   
174.
Amati D  Shallice T 《Cognition》2007,103(3):358-385
The emergence of modern humans with their extraordinary cognitive capacities is ascribed to a novel type of cognitive computational process (sustained non-routine multi-level operations) required for abstract projectuality, held to be the common denominator of the cognitive capacities specific to modern humans. A brain operation (latching) that allows this novel computational process is proposed as well as a physics-inspired mechanism that could explain its rather recent emergence without invoking unlikely genetic or structural changes.  相似文献   
175.
176.
For humans and other species, the ability to estimate the physical passage of time is of fundamental importance for perceptual, cognitive or motor functions. Despite this importance, any subjective estimation of temporal durations not only depends on the temporal dynamics of the to-be-timed stimulus or event, but also can be distorted by non-temporal perceptual, cognitive, and emotional effects. This study aimed to further explore critical stimulus characteristics modulating distracter-induced distortions in human time-reproduction. To this end, we investigated whether subjectively rated distracter dimensions of arousal and valence (related to levels of emotionality), or rather stimulus complexity, as a confounder, produce distortions in participants' reproduction of a previously trained target interval. Accuracy and precision of time-reproduction have been measured in distracter-trials, and compared to timing performance in baseline-trials without any distraction. Results showed temporal overproductions in a magnitude of less than distracter duration only for complex distracters. Most importantly, arousal level and valence of distracters were not accountable for temporal distortions. Within an internal clock framework, our pattern of results can best be interpreted in the context of attention-, rather than arousal-based mechanisms of timing.  相似文献   
177.
Emotional effects on human time perception are generally attributed to arousal speeding up or slowing down the internal clock. The aim of the present study is to investigate the less frequently considered role of attention as an alternative mediator of these effects with the help of event-related potentials (ERPs). Participants produced short intervals (0.9, 1.5, 2.7, and 3.3 s) while viewing high arousal images with pleasant and unpleasant contents in comparison to neutral images. Behavioral results revealed that durations were overproduced for the 0.9 s interval whereas, for 2.7 and 3.3 s intervals, underproduction was observed. The effect of affective valence was present for the shorter durations and decreased as the target intervals became longer. More specifically, the durations for unpleasant images were less overproduced in the 0.9 s intervals, and for the 1.5 s trials, durations for unpleasant images were slightly underproduced, compared to pleasant images, which were overproduced. The analysis of different ERP components suggests possible attention processes related to the timing of affective images in addition to changes in pacemaker speed. Early Posterior Negativity (EPN) was larger for positive than for negative images, indicating valence-specific differences in activation of early attention mechanisms. Within the early P1 and the Late Positive Potential (LPP) components, both pleasant and unpleasant stimuli exhibited equal affective modulation. Contingent Negative Variation (CNV) remained independent of both timing performance and affective modulation. This pattern suggests that both pleasant and unpleasant stimuli enhanced arousal and captured attention, but the latter effect was more pronounced for pleasant stimuli. The valence-specificity of affective attention revealed by ERPs combined with behavioral timing results suggests that attention processes indeed contribute to emotion-induced temporal distortions, especially for longer target intervals.  相似文献   
178.
Previous research suggests that time perception is supported by the same attentional resources involved in sequence processing. The present experiment was designed to clarify this connection by examining the relation between timing and reasoning tasks that involved either sequencing or non-sequencing judgments. For the timing task, subjects produced a series of 5-s intervals. For the reasoning tasks, subjects judged whether pairs of statements describing common actions either (a) were presented in the correct temporal order (sequencing), or (b) described similar actions or objects (similarity). Subjects performed the timing and reasoning tasks both separately and concurrently in a series of 3-minute trials. Comparisons of single-task and dual-task performance assessed interference patterns between concurrent tasks. Both reasoning tasks interfered with timing by making temporal productions longer and more variable. Timing had differential effects on the two reasoning tasks. Concurrent timing caused sequencing judgments to become slower, less accurate, and less sensitive relative to sequencing-only conditions. In contrast, similarity judgments were either unaffected or affected to a lesser degree by the concurrent timing task. These results support the notion that timing and sequencing are closely related processes that rely on the same set of cognitive resources or mechanisms.  相似文献   
179.
Traditional methods for deriving property‐based representations of concepts from text have focused on either extracting only a subset of possible relation types, such as hyponymy/hypernymy (e.g., car is‐a vehicle ) or meronymy/metonymy (e.g., car has wheels ), or unspecified relations (e.g., car — petrol ). We propose a system for the challenging task of automatic, large‐scale acquisition of unconstrained, human‐like property norms from large text corpora, and discuss the theoretical implications of such a system. We employ syntactic, semantic, and encyclopedic information to guide our extraction, yielding concept‐relation‐feature triples (e.g., car be fast , car require petrol , car cause pollution ), which approximate property‐based conceptual representations. Our novel method extracts candidate triples from parsed corpora (Wikipedia and the British National Corpus) using syntactically and grammatically motivated rules, then reweights triples with a linear combination of their frequency and four statistical metrics. We assess our system output in three ways: lexical comparison with norms derived from human‐generated property norm data, direct evaluation by four human judges, and a semantic distance comparison with both WordNet similarity data and human‐judged concept similarity ratings. Our system offers a viable and performant method of plausible triple extraction: Our lexical comparison shows comparable performance to the current state‐of‐the‐art, while subsequent evaluations exhibit the human‐like character of our generated properties.  相似文献   
180.
Adaptive cruise control (ACC), a driver assistance system that controls longitudinal motion, has been introduced in consumer cars in 1995. A next milestone is highly automated driving (HAD), a system that automates both longitudinal and lateral motion. We investigated the effects of ACC and HAD on drivers’ workload and situation awareness through a meta-analysis and narrative review of simulator and on-road studies. Based on a total of 32 studies, the unweighted mean self-reported workload was 43.5% for manual driving, 38.6% for ACC driving, and 22.7% for HAD (0% = minimum, 100 = maximum on the NASA Task Load Index or Rating Scale Mental Effort). Based on 12 studies, the number of tasks completed on an in-vehicle display relative to manual driving (100%) was 112% for ACC and 261% for HAD. Drivers of a highly automated car, and to a lesser extent ACC drivers, are likely to pick up tasks that are unrelated to driving. Both ACC and HAD can result in improved situation awareness compared to manual driving if drivers are motivated or instructed to detect objects in the environment. However, if drivers are engaged in non-driving tasks, situation awareness deteriorates for ACC and HAD compared to manual driving. The results of this review are consistent with the hypothesis that, from a Human Factors perspective, HAD is markedly different from ACC driving, because the driver of a highly automated car has the possibility, for better or worse, to divert attention to secondary tasks, whereas an ACC driver still has to attend to the roadway.  相似文献   
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