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861.
K. S. R. Anjaneyulu 《Resonance》1998,3(3):46-58
Expert systems encode human expertise in limited domains by representing it usingif-then rules. This article explains the development and applications of expert systems. 相似文献
862.
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865.
Paul S. R. Goods Brian Dawson Grant J. Landers Christopher J. Gore Kevin Croft Peter Peeling 《European Journal of Sport Science》2016,16(8):1047-1054
This investigation examined the oxidative stress (F2-Isoprostane; F2-IsoP) and inflammatory (interleukin-6; IL-6) responses to repeat-sprint training in hypoxia (RSH). Ten trained male team sport athletes performed 3(sets)*9(repetitions)*5?s cycling sprints in simulated altitude (3000?m) and sea-level conditions. Mean and peak sprint power output (MPO and PPO) were recorded, and blood samples were collected pre-exercise, and again at 8 and 60?min post-exercise. Both MPO and PPO were significantly reduced in hypoxia (compared to sea-level) in the second (MPO: 855?±?89 vs. 739?±?95?W, p?=?.006; PPO: 1024?±?114 vs. 895?±?112?W, p?=?.010) and third (MPO: 819?±?105 vs. 686?±?83?W, p?=?.008; PPO: 985?±?125 vs. 834?±?99?W, p?=?.008) sets, respectively. IL-6 was significantly increased from pre- to 1?h post-exercise in both hypoxia (0.7?±?0.2 vs. 2.4?±?1.4?pg/mL, p?=?.004) and sea-level conditions (0.7?±?0.2 vs. 1.6?±?0.3?pg/mL, p?.001), with a large effect (d?=?0.80) suggesting higher IL-6 levels of post-hypoxia. F2-IsoP was significantly lower 1?h post-exercise in both the hypoxic (p?=?.005) and sea-level (p?=?.002) conditions, with no differences between trials. While hypoxia can impact on exercise intensity and may result in greater post-exercise inflammation, it appears to have little effect on oxidative stress. These results indicate that team sport organisations with ready access to hypoxic training facilities could confidently administer RSH without significantly increasing the post-exercise inflammatory or oxidative stress response. 相似文献
866.
Lick suppression experiments with rats revealed that the magnitude of both second-order conditioning (Experiment 1) and sensory preconditioning (Experiment 2) was superior when that conditioning was based on backward (US→CS) relative to forward (CS→US) first-order pairings of a CS and US. The superiority of backward relative to forward first-order conditioning on suppression to the higher order cues can be understood by assuming that the magnitude of higher order conditioning was determined by a memory representation of the higher order cues that provided information about the expected temporal location of the US. The results suggest that temporal information such as order between paired CSs and USs was encoded, preserved, and integrated with memory for the higher order stimuli. The relevance of these findings to memory integration in Pavlovian learning, the temporal coding hypothesis (Barnet, Arnold, & Miller, 1991; Matzel, Held, & Miller, 1988), backward excitatory conditioning, and the associative structure that underlies second-order Pavlovian fear conditioning are discussed. 相似文献
867.
This study examined parent reports of behavioral and family functioning for 59 boys with learning disabilities (LD) and 65 nondisabled boys (NLD) of ages 6 to 12 years. Parents completed the Child Behavior Checklist (CBCL) and the Family Adaptability and Cohesion Evaluation Scale (FACES III). Boys with LD were reported as having significantly more behavior problems of both the Internalizing and Externalizing types than NLD boys. Individual scales yielded group differences indicating higher scores (more problems) for the group with LD on the Hyperactive, Schizoid or Anxious, Depressed, and Obsessive Compulsive scales, but no differences on the Aggressive or Social Withdrawal scales. Furthermore, families of boys with LD tended to score more frequently in the extreme (disturbed) range of family functioning. However, boys of families in the extreme range did not have more behavior problems than the boys of other families. The findings suggest that a greater than average proportion of boys with LD are at risk for developing psychological adjustment problems. 相似文献
868.
Cognitive deficits in reading disability and attention deficit disorder 总被引:12,自引:0,他引:12
This paper presents data from three studies (a cross-sectional study of school-referred children, a test-retest study of subtypes of reading disabilities, and a study of a large, random sample of first graders) that focus on specifying the cognitive deficits associated with reading difficulties and separating them from those associated with attentional deficits. The cognitive deficits associated with difficulty in reading were consistent across samples, developmental levels, definitions, and subtypes of reading disabilities. With IQ, age, and sex controlled for, poor readers were significantly impaired on measures of naming and phonological awareness. The effects of attentional deficits were more variable and complex but were clearly separate from the reading disability effects. 相似文献
869.
Two groups of gifted adolescents solved two similar intelligence tests with differing levels of task difficulty in reverse order. Under both conditions the performance level on the less complex test was much lower, a result not observed in a control group of average intelligence. Behavioural observations revealed that the low performance of the gifted students was combined with lack of effort. This performance pattern is discussed with respect to recent postulates of achievement motivation theory, which empasize the impact not only of the achievement motive, but also of the informational value of a given task for evaluating own level of ability. It is argued that the perceived informational value of the easier test was not high enough to create an incentive for the gifted students to perform at the highest possible level 相似文献
870.
Using Family Backpacks as a Tool to Involve Families in Teaching Young Children About Healthy Eating
Jisoo Hong Diane W. Bales Charlotte R. Wallinga 《Early Childhood Education Journal》2018,46(2):209-221
Children’s obesity rates have increased substantially over the past several decades, due in part to unhealthy eating habits. About 75% of preschool-aged children consume fewer fruits and vegetables than recommended for health. Because children begin developing eating habits during early childhood, obesity prevention programs are increasingly targeting young children in early childhood education (ECE) settings and are involving their families in teaching about healthy eating. The purpose of this pilot study is to assess the effectiveness of a family involvement activity known as the family backpack in increasing fruit and vegetable consumption among 4- and 5-year-old children and their parents through hands-on activities that encourage them to explore and discuss fruits and vegetables at home. Forty-two families (22 experimental, 20 control) participated in the study. Families received a family backpack from their child’s ECE teacher and completed activities with their child at home during a specific week. Experimental-group backpacks contained a children’s book and three activities to encourage parent–child discussion about fruits and vegetables; control-group backpacks contained an unrelated book and activities. Children’s and parents’ fruit and vegetable consumption and frequency of serving fruits and vegetables at home were assessed using parent self-report surveys before and after completing backpack activities. Parents in the experimental group, but not the control group, reported increases in their own and their children’s fruit and vegetable consumption after completing family backpack activities. Family backpacks show promise as a tool for early childhood educators to help families reinforce and expand children’s learning and encourage healthy eating habits at home. 相似文献