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101.
Stress and hypothalamic-pituitary-adrenal (HPA) axis dysregulation have been associated with externalizing behavior in adolescence, but few studies have examined these factors in a treatment context. This study investigated the relationship between stress, cortisol, and externalizing behavior among 120 adolescent males (mean age?=?15) receiving Multisystemic Therapy (MST). To examine the differential relationship of cortisol with various types of stressors, self-report measures assessed lifetime stress, current episodic stress, and daily hassles. Morning and afternoon cortisol samples were collected to examine whether the relationship between stress and treatment outcome depended on the youth's biological stress levels. Regression analyses indicated that awakening cortisol levels moderated the relationship between daily hassles and externalizing behaviors at post-treatment. More specifically, higher levels of daily hassles predicted worse outcomes only among adolescents with high levels of morning cortisol. In addition, lifetime stressors and afternoon measures of cortisol interacted to predict changes in caretaker reports of externalizing problems and youth arrests following treatment; lifetime stressors were positively associated with externalizing behavior when adolescents had low levels of afternoon cortisol. Implications for theory and future directions for evidence-based treatment are discussed.  相似文献   
102.
Tripping and falling is a serious health problem for older citizens due to the high medical costs incurred and the high mortality rates precipitated mostly by hip fractures that do not heal well. Current falls prevention technology encompasses a broad range of interventions; both passive (e.g., safer environments, hip protectors) and active (e.g., sensor-based fall detectors) which attempt to reduce the effects of tripping and falling. However the majority of these interventions minimizes the impact of falls and do not directly reduce the risk of falling. This paper investigates the prediction of gait parameters related to foot-to-ground clearance height during the leg swing phase which have been physically associated with tripping and falling risk in the elderly. The objective is to predict parameters of foot trajectory several walking cycles in advance so that anticipated low foot clearance could be addressed early with more volitional countermeasures, e.g., slowing down or stopping. In this primer study, foot kinematics was recorded with a highly accurate motion capture system for 10 healthy adults (25-32 years) and 11 older adults (65-82 years) with a history of falls who each performed treadmill walking for at least 10 min. Vertical foot displacement during the swing phase has three characteristic inflection points and we used these peak values and their normalized time as the target prediction values. These target variables were paired with features extracted from the corresponding foot acceleration signal (obtained through double differentiation). A generalized regression neural network (GRNN) was used to independently predict the gait variables over a prediction horizon (number of gait cycles ahead) of 1-10 gait cycles. It was found that the GRNN attained 0.32-1.10 cm prediction errors in the peak variables and 2-8% errors in the prediction of normalized peak times, with slightly better accuracies in the healthy group compared to elderly fallers. Prediction accuracy decreased linearly (best fit) at a slow rate with increasing prediction horizon ranging from 0.03 to 0.11 cm per step for peak displacement variables and 0.34 × 10(-3) - 1.81 × 10(-3)% per step for normalized peak time variables. Further time series analysis of the target gait variable revealed high autocorrelations in the faller group indicating the presence of cyclic patterns in elderly walking strategies compared to almost random walking patterns in the healthy group. The results are promising because the technique can be extended to portable sensor-based devices which measure foot accelerations to predict the onset of risky foot clearance, thus leading to a more effective falls prevention technology.  相似文献   
103.
Contrasts of means are often of interest because they describe the effect size among multiple treatments. High-quality inference of population effect sizes can be achieved through narrow confidence intervals (CIs). Given the close relation between CI width and sample size, we propose two methods to plan the sample size for an ANCOVA or ANOVA study, so that a sufficiently narrow CI for the population (standardized or unstandardized) contrast of interest will be obtained. The standard method plans the sample size so that the expected CI width is sufficiently small. Since CI width is a random variable, the expected width being sufficiently small does not guarantee that the width obtained in a particular study will be sufficiently small. An extended procedure ensures with some specified, high degree of assurance (e.g., 90% of the time) that the CI observed in a particular study will be sufficiently narrow. We also discuss the rationale and usefulness of two different ways to standardize an ANCOVA contrast, and compare three types of standardized contrast in the ANCOVA/ANOVA context. All of the methods we propose have been implemented in the freely available MBESS package in R so that they can be easily applied by researchers.  相似文献   
104.
Language for number is an important case study of the relationship between language and cognition because the mechanisms of non-verbal numerical cognition are well-understood. When the Pirahã (an Amazonian hunter-gatherer tribe who have no exact number words) are tested in non-verbal numerical tasks, they are able to perform one-to-one matching tasks but make errors in more difficult tasks. Their pattern of errors suggests that they are using analog magnitude estimation, an evolutionarily- and developmentally-conserved mechanism for estimating quantities. Here we show that English-speaking participants rely on the same mechanisms when verbal number representations are unavailable due to verbal interference. Followup experiments demonstrate that the effects of verbal interference are primarily manifest during encoding of quantity information, and—using a new procedure for matching difficulty of interference tasks for individual participants—that the effects are restricted to verbal interference. These results are consistent with the hypothesis that number words are used online to encode, store, and manipulate numerical information. This linguistic strategy complements, rather than altering or replacing, non-verbal representations.  相似文献   
105.
106.
This study examined the effects of visual-verbalload (as measured by a visually presented reading-memory task with three levels) on a visual/auditory stimulus-response task. The three levels of load were defined as follows: "No Load" meant no other stimuli were presented concurrently; "Free Load" meant that a letter (A, B, C, or D) appeared at the same time as the visual or auditory stimulus; and "Force Load" was the same as "Free Load," but the participants were also instructed to count how many times the letter A appeared. The stimulus-response task also had three levels: "irrelevant," "compatible," and "incompatible" spatial conditions. These required different key-pressing responses. The visual stimulus was a red ball presented either to the left or to the right of the display screen, and the auditory stimulus was a tone delivered from a position similar to that of the visual stimulus. Participants also processed an irrelevant stimulus. The results indicated that participants perceived auditory stimuli earlier than visual stimuli and reacted faster under stimulus-response compatible conditions. These results held even under a high visual-verbal load. These findings suggest the following guidelines for systems used in driving: an auditory source, appropriately compatible signal and manual-response positions, and a visually simplified background.  相似文献   
107.
108.

Purpose

To find out what information children, parents and education staff feel would be important to know to support a child who stutters in the educational environment, in order to develop appropriate resources.

Method

A Delphi study was carried out to seek the opinions of experts about the information to include. A structured six stage process was completed in order to gain consensus within four expert panels: children who stutter (CWS) aged 7-11 (n = 25); young people who stutter aged 12-18 (n = 27); parents of children and young people who stutter aged 2-18 (n = 67); and members of the education workforce (n = 35).

Results

In response to the questions, 538 statements were generated across the four expert panels, categorised and reduced to 276. Of the 154 rating questionnaires sent out, 99 were returned (64.2% response rate). The top 32 statements, which were those most highly rated and with the greatest consensus, were retained to inform the resources.

Conclusions

This study demonstrates the value of including service users when devising materials aimed for the benefit of CWS. The methodology employed ensured that ideas, perceptions and needs were representative of a range of people who experience stuttering from different perspectives. The results indicated that each expert panel had different priorities of what should be included. The resulting resources may therefore be considered to have high content validity and would be predicted to meet the needs of those who require them.Educational Objectives: The reader will be able to (1) define the Delphi Approach (2) discuss the development of a user led resource for raising awareness about stuttering.  相似文献   
109.
This article aims to investigate the training effect of working memory in older adults. A total of 43 older adults ranging in age from 75 to 95 were recruited to participate in the study. A battery of tests regarding central executive function, working memory, and primary mental ability were administered in the pretest phase. A total of 22 of the older participants were randomly selected as the intervention group. Thirteen days after the pretest, the same tests were administered to all of the participants. The results showed that (1) the differences in the pretest and posttest gains in the task-switching tests were not significant between the intervention group and the control group; (2) the performance of the intervention group on the operation working memory span test and the graphical reasoning test showed a significant improvement after the intervention compared with the control group who did not receive the intervention. We can conclude that the working memory of old adults may be improved by an intervention targeting the central executive system. However, this possibility needs further investigation.  相似文献   
110.
Abstract

At the ‘Embodied Ministry: Gender, Sexuality and Formation’ conference at which the articles in this special issue were delivered, three people in active ministry in different denominations — United Reformed Church, Metropolitan Community Church and Roman Catholic — were invited to take part in a panel discussion on gender and sexuality in the pastoral encounter. Their remarks were originally delivered in this conversational context. Martin Pendergast chaired this panel discussion.  相似文献   
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