967 resultados para adults fears about the effects of computer games


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Managing heat produced by computer processors is an important issue today, especially when the size of processors is decreasing rapidly while the number of transistors in the processor is increasing rapidly. This poster describes a preliminary study of the process of adding carbon nanotubes (CNTs) to a standard silicon paste covering a CPU. Measurements were made in two rounds of tests to compare the rate of cool-down with and without CNTs present. The silicon paste acts as an interface between the CPU and the heat sink, increasing the heat transfer rate away from the CPU. To the silicon paste was added 0.05% by weight of CNTs. These were not aligned. A series of K-type thermocouples was used to measure the temperature as a function of time in the vicinity of the CPU, following its shut-off. An Omega data acquisition system was attached to the thermocouples. The CPU temperature was not measured directly because attachment of a thermocouple would have prevented its automatic shut-off A thermocouple in the paste containing the CNTs actually reached a higher temperature than the standard paste, an effect easily explained. But the rate of cooling with the CNTs was about 4.55% better.

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This paper provides the first description of the mangrove cockle, Anadara spp., fisheries throughout their Latin American range along the Pacific coast from Mexico to Peru. Two species, A. tuberculosa and A. grandis, are found over the entire range, while A. similis occurs from El Salvador to Peru. Anadara tuberculosa is by far the most abundant, while A. grandis has declined in abundance during recent decades. Anadara tuberculosa and A. similis occur in level mud sediments in mangrove swamps, comprised mostly of Rhizophora mangle, which line the main-lands and islands of lagoons, whereas A. grandis inhabits intertidal mud flats along the edges of the same mangrove swamps. All harvested cockles are sexually mature. Gametogenesis of the three species occurs year round, and juvenile cockles grow rap-idly. Cockle densities at sizes at least 16–42 mm long ranged from 7 to 24/m2 in Mexico. Macrofaunal associates of cockles include crustaceans, gastropods, and finfishes. The mangrove swamps are in nearly pristine condition in every country except Honduras, Ecuador, and Peru, where shrimp farms constructed in the 1980’s and 1990’s have destroyed some mangrove zones. In addition, Hurricane Mitch destroyed some Honduran mangrove swamps in 1998. About 15,000 fishermen, including men, women, and children, harvest the cockles. Ecuador has the largest tabulated number of fishermen, 5,055, while Peru has the fewest, 75. Colombia has a large number, perhaps exceeding that in Ecuador, but a detailed census of them has never been made. The fishermen are poor and live a meager existence; they do not earn sufficient money to purchase adequate food to allow their full health and growth potential. They travel almost daily from their villages to the harvesting areas in wooden canoes and fiberglass boats at low tide when they can walk into the mangrove swamps to harvest cockles for about 4 h. Harvest rates, which vary among countries owing to differences in cockle abundances, range from about 50 cockles/fisherman/day in El Salvador and Honduras to 500–1,000/ fisherman/day in Mexico. The fishermen return to their villages and sell the cockles to dealers, who sell them mainly whole to market outlets within their countries, but there is some exporting to adjacent countries. An important food in most countries, the cockles are eaten in seviche, raw on the half-shell, and cooked with rice. The cockles are under heavy harvesting pressure, except in Mexico, but stocks are not yet being depleted because they are harvested at sizes which have already spawned. Also some spawning stocks lie within dense mangrove stands which the fishermen cannot reach. Consumers fortunately desire the largest cockles, spurning the smallest. Cockles are important to the people, and efforts to reduce the harvests to prevent overfishing would lead to severe economic suffering in the fishing communities. Pro-grams to conserve and improve cockle habitats may be the most judicious actions to take. Preserving the mangrove swamps intact, increasing their sizes where possible, and controlling cockle predators would lead to an increase in cockle abundance and harvests. Fishes that prey on juvenile cockles might be seined along the edges of swamps before the tide rises and they swim into the swamps to feed. Transplanting mangrove seedlings to suitable areas might increase the size of those habitats. The numbers of fishermen may increase in the future, because most adults now have several children. If new fishermen are tempted to harvest small, immature cockles and stocks are not increased, minimum size rules for harvestable cockles could be implemented and enforced to ensure adequate spawning.

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The influence of communication technology on group decision-making has been examined in many studies. But the findings are inconsistent. Some studies showed a positive effect on decision quality, other studies have shown that communication technology makes the decision even worse. One possible explanation for these different findings could be the use of different Group Decision Support Systems (GDSS) in these studies, with some GDSS better fitting to the given task than others and with different sets of functions. This paper outlines an approach with an information system solely designed to examine the effect of (1) anonymity, (2) voting and (3) blind picking on decision quality, discussion quality and perceived quality of information.

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In three related experiments, 250 participants rated properties of their autobiographical memory of a very negative event before and after writing about either their deepest thoughts and emotions of the event or a control topic. Levels of emotional intensity of the event, distress associated with the event, intrusive symptoms, and other phenomenological memory properties decreased over the course of the experiment, but did not differ by writing condition. We argue that the act of answering our extensive questions about a very negative event led to the decrease, thereby masking the effects of expressive writing. To show that the changes could not be explained by the mere passage of time, we replicated our findings in a fourth experiment in which all 208 participants nominated a very negative event, but only half the participants rated properties of their memory in the first session. Implications for reducing the effects of negative autobiographical memories are discussed.

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Use of structuring mechanisms (such as modularisation) is widely believed to be one of the key ways to improve software quality. Structuring is considered to be at least as important for specification documents as for source code, since it is assumed to improve comprehensibility. Yet, as with most widely held assumptions in software engineering, there is little empirical evidence to support this hypothesis. Also, even if structuring can be shown to he a good thing, we do not know how much structuring is somehow optimal. One of the more popular formal specification languages, Z, encourages structuring through its schema calculus. A controlled experiment is described in which two hypotheses about the effects of structure on the comprehensibility of Z specifications are tested. Evidence was found that structuring a specification into schemas of about 20 lines long significantly improved comprehensibility over a monolithic specification. However, there seems to be no perceived advantage in breaking down the schemas into much smaller components. The experiment can he fully replicated.

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The strength and nature of the video game practice effect on tests of visual and perceptual skills were examined using high functioning Grades Four and Five students who had been tested with the WISC-R .for the purpose of gifted identification and placement. The control group, who did not own and .play video games on a sustained basis, and the experimental group, who did own a video game system and had some mastery of video games, including the -Nintendo game, "Tetris", were each composed of 18 juniorg:r;-ade students and were chosen from pre-existing conditions. The experimental group corresponded to the control group in terms of age, sex, and community. Data on the Verbal and Performance I.Q. Scores were· collected for both groups and the author was interested in the difference between the Verbal and Performance Scores within each group, anticipating a P > V outcome for the experimental group. The results showed a significant P > V difference in the experimental, video game playing group, as expected, but no significant difference between the Performance $cores of the control and experimental groups. The results, thus, indicated lower Verbal I.Q. Scores in the experimental group relat'ive to 'the control group.' The study conclu~ed that information about a sUbject's video game experience and "learhing style pref~rence is important for a clear interpretation of the Verbal and Performance I.Q. Scores of the WISC-R. Although the time spent on video game play may, 'indeed, increase P~rformance Scores relative to Verbal Scores for an individual, the possibilities exist that the time borrowed and spent away from language based activities may retard verbal growth and/or that the cognitive style associated with some Performance I.Q.subtests may have a negative effect on the approach to the tasks on the Verbal I.Q. Scale. The study also discussed the possibility that exposure to ,the video game experience, in pre-puberty, can provide spatial instruction which will result in improved spatial skills. strong spatial skills have been linked to improved performance and preference in mathematics, science, and engineering and it was suggested that appropriate video game play might be a way to involve girls more in the fields of mathematics and science.

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It is well established that postural threat modifies postural control, although little is known regarding the underlying mechanism(s) responsible. It is possible that changes in postural control under conditions of elevated postural threat result from alterations in cognitive strategies. The purpose of this study was to determine the influence of elevated postural threat on cognitive strategies and to determine the relationship between postural control, psychological, and cognitive measures. It was hypothesized that elevated postural threat would cause a shift to more conscious control of posture. It was also expected that a relationship between fear of falling and postural control would exist that could be explained by changes in conscious control of posture. Forty-eight healthy young adults stood on a force plate at two different surface heights: ground level (LOW) and 3.2m above ground level (HIGH). Center of pressure (COP) summary measures calculated to quantify postural control were the mean position (AP-COP MP), root mean square (AP-COP RMS) and mean power frequency (AP-COP MPF) in the anteriorposterior direction. Trunk sway measures calculated in the pitch direction were trunk angle and trunk velocity. Psychological measures including perceived balance confidence, perceived fear of falling, perceived anxiety, and perceived stability were self reported. As a physiological indicator of anxiety, electrodermal activity was collected. The cognitive strategies assessed were movement reinvestment and attention focus. A modified state-sp-ecific version of the Movement Specific Reinvestment Scale was used to measure conscious motor processing (CMP) and movement self-consciousness (MSC). An attention focus questionnaire was developed to assess the amount of attention directed to internal and external sources. An effect of postural threat on cognitive strategies was observed as participants reported more conscious control and a greater concern or worry about their posture at the HIGH postural threat condition as well as an increased internal and external focus of attention. In addition changes in postural control, psychological, and physiological measures were found. The participants leaned away from the edge of the platform, the frequency of their postural adjustments increased, and the velocity of their trunk movements increased. Participants felt less confident, more fearful, more anxious, and less stable with an accompanying increase in physiological anxiety. Significant correlations between perceived anxiety, AP-COP MP, and cognitive measures revealed a possible relationship that could be mediated by cognitive measures. It was found that with greater conscious motor processing, more movement self-consciousness, and a greater amount of attention focused externally there was a larger shift of the mean position away from the edge of the platform. This thesis provides evidence that postural threat can influence cognitive strategies causing a shift to more conscious control of movement which is associated with leaning away from the edge of the platform. Shifting the position of the body away from the direction of the postural threat may reflect a cognitive strategy to ensure safety in this situation due to the inability to employ a stepping strategy when standing on an elevated platform.

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Older adults represent the most sedentary segment of the adult population, and thus it is critical to investigate factors that influence exercise behaviour for this age group. The purpose of this study was to examine the influence of a general exercise program, incorporating cardiovascular, strength, flexibility, and balance components, on task selfefficacy and SPA in older adult men and women. Participants (n=114, Mage = 67 years) were recruited from the Niagara region and randomly assigned to a 12-week supervised exercise program or a wait-list control. Task self-efficacy and SPA measures were taken at baseline and program end. The present study found that task self-efficacy was a significant predictor of leisure time physical activity for older adults. In addition, change in task self-efficacy was a significant predictor of change in SPA. The findings of this study suggest that sources of task self-efficacy should be considered for exercise interventions targeting older adults.

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The current thesis investigated the effects of a 12-week multifactorial exercise and balance training program on balance control in older adults. Participants completed a baseline testing session which included a series of questionnaires, anthropometric measures, and 18 stance and walking tests. Those who were randomly assigned to the exercise group participated in the 12-week training program while the comparison group was asked not to change anything in his/her lifestyle during the 12-week control period, but were invited to participate in the training program after his/her control period. The same testing protocol was repeated after the 12-week period. The results indicated that there were improvements in the time to complete the walking tests but no change in trunk sway in both the exercise and comparison groups. No changes in stance durations or trunk sway were observed. The findings suggest that the current training program showed no significant improvement in balance control in healthy older adults.

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Previously, studies investigating emotional face perception - regardless of whether they involved adults or children - presented participants with static photos of faces in isolation. In the natural world, faces are rarely encountered in isolation. In the few studies that have presented faces in context, the perception of emotional facial expressions is altered when paired with an incongruent context. For both adults and 8- year-old children, reaction times increase and accuracy decreases when facial expressions are presented in an incongruent context depicting a similar emotion (e.g., sad face on a fear body) compared to when presented in a congruent context (e.g., sad face on a sad body; Meeren, van Heijnsbergen, & de Gelder, 2005; Mondloch, 2012). This effect is called a congruency effect and does not exist for dissimilar emotions (e.g., happy and sad; Mondloch, 2012). Two models characterize similarity between emotional expressions differently; the emotional seed model bases similarity on physical features, whereas the dimensional model bases similarity on underlying dimensions of valence an . arousal. Study 1 investigated the emergence of an adult-like pattern of congruency effects in pre-school aged children. Using a child-friendly sorting task, we identified the youngest age at which children could accurately sort isolated facial expressions and body postures and then measured whether an incongruent context disrupted the perception of emotional facial expressions. Six-year-old children showed congruency effects for sad/fear but 4-year-old children did not for sad/happy. This pattern of congruency effects is consistent with both models and indicates that an adult-like pattern exists at the youngest age children can reliably sort emotional expressions in isolation. In Study 2, we compared the two models to determine their predictive abilities. The two models make different predictions about the size of congruency effects for three emotions: sad, anger, and fear. The emotional seed model predicts larger congruency effects when sad is paired with either anger or fear compared to when anger and fear are paired with each other. The dimensional model predicts larger congruency effects when anger and fear are paired together compared to when either is paired with sad. In both a speeded and unspeeded task the results failed to support either model, but the pattern of results indicated fearful bodies have a special effect. Fearful bodies reduced accuracy, increased reaction times more than any other posture, and shifted the pattern of errors. To determine whether the results were specific to bodies, we ran the reverse task to determine if faces could disrupt the perception of body postures. This experiment did not produce congruency effects, meaning faces do not influence the perception of body postures. In the final experiment, participants performed a flanker task to determine whether the effect of fearful bodies was specific to faces or whether fearful bodies would also produce a larger effect in an unrelated task in which faces were absent. Reaction times did not differ across trials, meaning fearful bodies' large effect is specific to situations with faces. Collectively, these studies provide novel insights, both developmentally and theoretically, into how emotional faces are perceived in context.

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Objectives - To assess the general public's interpretation of the verbal descriptors for side effect frequency recommended for use in medicine information leaflets by a European Union (EU) guideline, and to examine the extent to which differences in interpretation affect people's perception of risk and their judgments of intention to comply with the prescribed treatment. Method - Two studies used a controlled empirical methodology in which people were presented with a hypothetical, but realistic, scenario about visiting their general practitioner and being prescribed medication. They were given an explanation that focused on the side effects of the medicine, together with information about the probability of occurrence using either numerical percentages or the corresponding EU verbal descriptors. Interpretation of the descriptors was assessed. In study 2, participants were also required to make various judgments, including risk to health and intention to comply. Key findings - In both studies, use of the EU recommended descriptors led to significant overestimations of the likelihood of particular side effects occurring. Study 2 further showed that the "overestimation" resulted in significantly increased ratings of perceived severity of side effects and risk to health, as well as significantly reduced ratings of intention to comply, compared with those for people who received the probability information in numerical form. Conclusion - While it is recognised that the current findings require replication in a clinical setting, the European and national authorities should suspend the use of the EU recommended terms until further research is available to allow the use of an evidence-based approach.

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Interpretation biases towards threat play a prominent role in cognitive theories of anxiety, and have been identified amongst highly anxious adults and children. Little is known, however, about the development of these cognitive biases although family processes have been implicated. The current study investigated the nature of threat interpretation of anxious children and their mothers through (i) comparison of a clinic and non-clinic population, (ii) analysis of individual differences; and (ill) pre- and post-treatment comparisons. Participants were 27 children with a primary anxiety disorder and 33 children from a non-clinic population and their mothers. Children and mothers completed self-report measures of anxiety and indicated their most likely interpretation of ambiguous scenarios. Clinic and non-clinical groups differed significantly on measures of threat interpretation. Furthermore, mothers' and children's threat interpretation correlated significantly. Following treatment for child anxiety, both children and their mothers reported a reduction in threat interpretation. (c) 2005 Elsevier Ltd. All rights reserved.

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Background: As people age, language-processing ability changes. While several factors modify discourse comprehension ability in older adults, syntactic complexity of auditory discourse has received scant attention. This is despite the widely researched domain of syntactic processing of single sentences in older adults. Aims: The aims of this study were to investigate the ability of healthy older adults to understand stories that differed in syntactic complexity, and its relation to working memory. Methods & Procedures: A total of 51 healthy adults (divided into three age groups) took part. They listened to brief stories (syntactically simple and syntactically complex) and had to respond to false/true comprehension probes following each story. Working memory capacity (digit span, forward and backward) was also measured. Outcomes & Results: Differences were found in the ability of healthy older adults to understand simple and complex discourse. The complex discourse in particular was more sensitive in discerning age-related language patterns. Only the complex discourse task correlated moderately with age. There was no correlation between age and simple discourse. As far as working memory is concerned, moderate correlations were found between working memory and complex discourse. Education did not correlate with discourse, neither simple, nor complex. Conclusions: Older adults may be less efficient in forming syntactically complex representations and this may be influenced by limitations in working memory.

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Given age-related memory impairments, one’s level of curiosity or interest could enhance memory for certain information. In the current study, younger and older adults read trivia questions, rated how curious they were to learn each answer, provided confidence and interest ratings, and judgments of learning (JOL) after learning the answer. No age-related differences in memory were found. Analyses indicated that curiosity and interest contributed to the formation of JOLs. Additionally, interest had a unique increasing relationship with older, but not younger, adults’ memory performance after a week. The results suggest that subjective interest may serve to enhance older adults’ memory.