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281.
282.
Two rhesus monkeys were tested in 6- and 10-item list memory tasks for performance changes as a function of the exposure duration of the list stimuli and the interstimulus interval (ISI) between successive list stimuli. Accuracy increased with longer item exposure duration and tended to decrease with longer ISI duration. Humans, by contrast, typically show increases in accuracy with ISI, a result taken as evidence of rehearsal. The decrease in accuracy for monkeys suggests that they were not using rehearsal processes in these list memory experiments. Further tests in which choice accuracy with predictable ISIs was compared with choice accuracy with unpredictable ISIs also yielded no evidence of rehearsal by the monkeys. This apparent absence of rehearsal mechanisms in monkeys, in situations also shown to support human rehearsal, is discussed as a potential difference in the visual working memory processes of the two species.  相似文献   
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This study aimed to examine the reliability of different power and velocity variables during the Smith machine bench press (BP) and bench press throw (BPT) exercises. Twenty-two healthy men conducted four testing sessions after a preliminary BP one-repetition maximum (1RM) test. In a counterbalanced order, participants performed two sessions of BP in one week and two sessions of BPT in another week. Mean propulsive power, peak power, mean propulsive velocity, and peak velocity at each tenth percentile (20–70% of 1RM) were recorded by a linear transducer. The within-participants coefficient of variation (CV) was higher for the load–power relationship compared to the load–velocity relationship in both the BP (5.3% vs. 4.1%; CV ratio = 1.29) and BPT (4.7% vs. 3.4%; CV ratio = 1.38). Mean propulsive variables showed lower reliability than peak variables in both the BP (5.4% vs. 4.0%, CV ratio = 1.35) and BPT (4.8% vs. 3.3%, CV ratio = 1.45). All variables were deemed reliable, with the peak velocity demonstrating the lowest within-participants CV. Based upon these findings, the peak velocity should be chosen for the accurate assessment of BP and BPT performance.  相似文献   
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The article describes the development and evaluation of a web-based pre-course in mathematics, delivered to four cohorts of engineering students at a German university. Based on demographic, personal, and learning-related data relationships between students’ preconditions, their learning gains in the pre-course, and study success in the degree programme were analysed. The results support the existing literature in that domain-related prior knowledge and secondary school achievement play a dominant role regarding study success in engineering. The analyses also showed that the influence of cognitive predictors could only be compensated for by a strong learner engagement. At-risk students with high pre-course learning gains showed significantly better first-year performance. The number of self-tests a student attempted was positively related to pre-course learning gains and even to first-year performance, suggesting that this variable is a good indicator of student engagement.  相似文献   
287.
The overall intent of this study is to examine the relationship among several factors that influence the malnutrition of a select group of Filipino elderly in institutionalized setting. A total of 102 residents were purposively recruited from three different institutionalized care settings at the national capital region of the Philippines. A multi-aspect questionnaire was used to characterize the demographic and nutrition profiles of the participants. Data were treated statistically using the partial least square design. Notably, the study showed that 48.0% of the elderly residents in institutions were at risk of malnutrition, 36.3% were malnourished, and 15.7% have normal nutritional status. Malnutrition was found to be prevalent among the female group, aged >70 years old, functional impairment (= <0.01), poor eating habits (= 0.01), lower dietary intake (= 0.01), and eating difficulties (= 0.04). However, statistically significant relationships between eating habits (= 0.08) and dietary intake and comorbidities (= 0.32) and malnutrition were not established. Impliedly, administrators of homecare institutions are invited to pay greater attention to the nutritional status of the elderly by institutionalizing nutrition assessment and evaluation practices and nutrition care planning that respond to the identified nutritional needs and concern of the elderly.  相似文献   
288.
Connecting to nature and spending time outdoors as children have been indicated as predictors of environmentally responsible behavior. This study examined whether a residential outdoor environmental education (ROEE) program contributed to the development of children’s connection to nature and their attitudes and involvement in spending time outdoors. Fifth-grade students (n = 163) in Pennsylvania enrolled in a multi-day ROEE program completed pretest-posttest surveys, compared with a control group (n = 72) not enrolled. Program evaluation critically examined the program’s encouragement of spending time outdoors by establishing connections to nature. Results indicated moderate success in the program’s effort to increase participants’ nature connection, but yielded mixed results on outcomes related to time spent outdoors. These findings offer encouragement of ROEE programs’ ability to foster connection to nature in participants.  相似文献   
289.
Reading relies on a left‐lateralized network of brain areas that include the pre‐lexical processing regions of the ventral stream. Specifically, a region in the left lateral occipitotemporal sulcus (OTS) is consistently more activated for visual presentations of words than for other categories of stimuli. This region undergoes dramatic changes at the functional and structural levels when children learn to read, but little is known about the effects of early cerebral constraints on reading skills. Using anatomical magnetic resonance imaging, we investigated whether the sulcal pattern of the lateral OTS—a stable brain feature—was associated with oral reading skills. The sulcal pattern of the left but not the right lateral OTS was associated with the number of words correctly read in 3 min. This study is the first to evidence that reading is affected by early cerebral constraints, such as the sulcal morphology of the left lateral OTS.  相似文献   
290.
Do siblings develop similar attachment relationships with their mother? Attachment theory suggests that brothers and sisters growing up in the same family are likely to relate in similar ways to their parents, at least when parental attachment representations and interactive styles remain stable across time. In the current study, sibling attachment data from three research groups (from Pennsylvania State University, Leiden University, and the University of Western Ontario) have been pooled to assemble a sufficiently large sample of observations (N = 138 sibling pairs) for a detailed comparison of sibling attachment relationships. Spacing between the births, differences in maternal sensitivity, and gender of siblings were examined as possible sources of concordance of nonconcordance. Attachment security (including disorganized attachment) of each sibling was assessed with the Strange Situation procedure between 12 and 14 months after birth. Maternal sensitivity was observed with the same rating scale in a laboratory play session in one of the studies and in home observations in the others. Sibling relationships were found to be significantly concordant when classified as secure/nonsecure (62% concordance, p < .01, 1-tailed, intraclass correlation = .23) but not when further subcategorized. Maternal insensitivity to both siblings (shared environment) was associated with concordance of sibling nonsecurity. Siblings of the same gender were more likely to form concordant relationships with their mother (68%; p < .01, 1-tailed, intraclass correlation = .37) than those of opposite gender. Same-sex sibling concordance was comparable to the concordance found for monozygotic twins in earlier studies. Genetic factors may, therefore, play a relatively small role in the development of attachment.  相似文献   
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