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871.
The primary purpose of this study was to examine adolescents' energy cost in a marching band. High school marching band participants (N=15) completed five 3-min. stages of treadmill marching, using a 57.2-cm stride length (typical standard of eight steps per five yards) as follows: without instruments at 75 m x min.(-1) and 132 steps x min.(-1) (Stage 1): without instruments at 91 m x min.(-1) and 160 steps x min.(-1) (Stage 2); carrying instruments at 75 m x min.(-1) and 132 steps x min.(-1) (Stage 3); carrying instruments at 91 m x min.(-1) and 160 steps x min.(-1) (Stage 4); and playing instruments at 75 m x min.(-1) and 132 steps x min.(-1) (Stage 5). Mean heart-rate response to an actual parade performance was similar to the mean Stage 5 treadmill heart rate (n=6). With regard to a high school marching band, these results suggest that energy demand for marching cadences approximates 4.5 and 6.0 metabolic equivalents for moderate and fast paces, respectively. 相似文献
872.
Graham EL 《Studies in Christian ethics》2003,16(1):29-43
This paper draws attention to the role of representation in the depiction of scientific and technological innovation as a means of understanding the narratives that circulate concerning the shape of things to come. It considers how metaphors play an important part in the conduct of scientific explanation, and how they do more than describe the world in helping also to shape expectations, normalise particular choices, establish priorities and create needs. In surveying the range of metaphorical responses to the digital and biotechnological age, we will see how technologies are regarded both as 'endangerment' and 'promise.' What we believe 'technology' is doing to 'us' reflects important implicit philosophies of technology and its relationship to human agency and political choice; yet we also need to be alert to the assumptions about 'human nature' itself which inform such reactions. The paper argues that embedded in the various representations implicit in the new technologies are crucial issues of identity, community and justice: what it means to be (post)human, who is (and who is not) entitled to the rewards of technological advancement, what priorities (and whose interests) will inform the shape of global humanity into the next century. 相似文献
873.
The aim of this study was to assess the effect of watching a psychological stressful event on the activation of leukocytes in healthy human volunteers. Blood samples were obtained from 32 healthy male and female subjects aged between 20 and 26 years before, during and after either watching an 83-minute horror film that none of the subjects had previously seen (The Texas Chainsaw Massacre, 1974) or by sitting quietly in a room (control group). Total differential cell counts, leukocyte activation as measured by the nitroblue tetrazolium (NBT) test, heart rate and blood pressure (BP) measurements were taken at defined time points. There were significant increases in peripheral circulating leukocytes, the number of activated circulating leukocytes, haemoglobin (Hb) concentration and haematocrit (Hct) in response to the stressor. These were accompanied by significant increases in heart rate, systolic and diastolic BP (P<0.05 from baseline). This is the first reported study on the effects of observing a psychologically stressful, albeit fictitious event on circulating leukocyte numbers and the state of leukocyte activation as determined by the nitrotetrazolium test. 相似文献
874.
A Meta-Analysis of Structural and Functional Brain Imaging in Dementia of the Alzheimer's Type: A Neuroimaging Profile 总被引:5,自引:0,他引:5
We conducted a quantitative review of the imaging literature using meta-analytic methodology to characterize further the magnitude of hippocampal deficit in probable Alzheimer's disease (AD) and to determine whether other neuroanatomic structures in AD can better discriminate the disease from normal aging. Additionally, we parceled the discriminability of neuroanatomic structures by duration of disease to determine those structures most sensitive to AD in its early and late stages. One hundred twenty-one studies published between 1984 and 2000 met criteria for inclusion in the present analysis. In total, structural (i.e., CT and MRI) and functional (i.e., SPECT and PET) neuroimaging results from 3511 patients with AD, and 1632 normal healthy controls were recorded across meta-analyses. Our results include neuroimaging profiles for both early onset and longer duration patients with AD. In sum, these profiles yield a signature of diagnostic markers in both cortical and subcortical neuroanatomic areas. This signature is consistent with the clinical phenomenology of Alzheimer's dementia and should aid in the positive identification of AD. 相似文献
875.
Three experiments investigated response times (RTs) for remember and know responses in recognition memory. RTs to remember responses were faster than RTs to know responses, regardless of whether the remember-know decision was preceded by an old/new decision (two-step procedure) or was made without a preceding old/new decision (one-step procedure). The finding of faster RTs for R responses was also found when remember-know decisions were made retrospectively. These findings are inconsistent with dual-process models of recognition memory, which predict that recollection is slower and more effortful than familiarity. Word frequency did not influence RTs, but remember responses were faster for words than for nonwords. We argue that the difference in RTs to remember and know responses reflects the time taken to make old/new decisions on the basis of the type of information activated at test. 相似文献
876.
Kennard BD Stewart SM Hughes JL Patel PG Emslie GJ 《Cultural diversity & ethnic minority psychology》2006,12(3):578-591
Cognitive models have guided effective intervention strategies in the treatment of depression. However, little is known about the cognitive model's relevance in different cultural ethnic groups in the United States. This study examines the cross-sectional and longitudinal associations among cognitive variables and depressive symptoms among African American, Caucasian, and Hispanic adolescents in the United States. Community adolescents (N = 450) ages 14-18 years (African American n = 79; Caucasian n = 273; Hispanic n = 98) provided information regarding their depressive symptoms and cognitions at two surveys, 6 months apart. Self-efficacy, cognitive errors, and hopelessness were associated with concurrent depressive symptoms at baseline. In addition, cognitive errors at baseline, controlling for baseline depressive symptoms and the occurrence of stressful events, predicted depressive symptoms at follow-up. Ethnic differences disappeared when parent education level was controlled. Our findings demonstrate support for the cognitive model of depression across ethnic groups. The importance of controlling for social class when examining ethnic differences in psychological variables is highlighted by our findings. 相似文献
877.
Current models of verbal short-term memory (STM) propose various mechanisms for serial order. These include a gradient of activation over items, associations between items, and associations between items and their positions relative to the start or end of a sequence. We compared models using a variant of Hebb's procedure in which immediate serial recall of a sequence improves if the sequence is presented more than once. However, instead of repeating a complete sequence, we repeated different aspects of serial order information common to training lists and a subsequent test list. In Experiment 1, training lists repeated all the item-item pairings in the test list, with or without the position-item pairings in the test list. Substantial learning relative to a control condition was observed only when training lists repeated item-item pairs with position-item pairs, and position was defined relative to the start rather than end of a sequence. Experiment 2 attempted to analyse the basis of this learning effect further by repeating fragments of the test list during training, where fragments consisted of either isolated position-item pairings or clusters of both position-item and item-item pairings. Repetition of sequence fragments led to only weak learning effects. However, where learning was observed it was for specific position-item pairings. We conclude that positional cues play an important role in the coding of serial order in memory but that the information required to learn a sequence goes beyond position-item associations. We suggest that whereas STM for a novel sequence is based on positional cues, learning a sequence involves the development of some additional representation of the sequence as a whole. 相似文献
878.
When participants confuse the position of items in immediate serial recall, they tend to recall transposed items too early rather than too late. This asymmetry of transposition errors was observed in four experiments. It increased as a function of list length, but was independent of report order, output position, cueing condition, and recall mode. The transposition asymmetry is consistent with error patterns in free recall and in regular speech production where transpositions are usually forward-looking. The asymmetry of transposition errors is discussed in terms of models of serial memory. 相似文献
879.
The ability of respondents to underreport successfully on substance abuse and validity scales of the Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A; Butcher et al., 1992) was evaluated. Incarcerated teens (67 substance abusing, 59 non-substance abusing) completed the MMPI-A twice: once under standard instructions (SI) and once under instructions to fake good (FG). Under SI, substance scales correctly classified about 60% to 85% of adolescents. Under FG, substance- and non-substance-abusing juveniles produced lower scores on substance scales. However, the Lie Scale (L) was able to detect more than 75% of deceptive profiles and about 77% of honest profiles. When scale L and the best substance scale were used in combination, only about 18% of faking substance abusers were not identified as either substance abusers or as underreporting. For feigning substance abusers, only about 10% of substance abusers were detected, with about 72% being categorized as faking and needing further assessment. 相似文献
880.
The present paper reports the results of two experiments designed to test predictions from the mood-as-input account of perseverative checking. Using an analogue checking task, both experiments showed that perseveration, as indicted by a range of measures relevant to compulsive checking, was affected by the configuration of the stop rule for the task and mood at the outset of checking. Perseveration was most significant in the condition that most closely resembled the characteristics of obsessive-compulsive checkers (negative mood combined with a stop rule that specifies that the task should be done as thoroughly as possible--namely, an 'as many as can' stop rule). The studies also indicated that confidence at having completed the checking task successfully was (1) significantly related to the use of 'as many as can' stop rules at the outset of checking, (2) mood ratings at the end of checking, and (3) checking perseveration generally. These findings provide support for a mood-as-input explanation of perseverative psychopathologies such as compulsive checking, and begin to cast some light on how anxiety-reduction and 'confidence' models of compulsive checking, might be explained within broader mechanisms of perseveration. 相似文献