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911.
Objective: The authors evaluated the time course of the treatment effect of Osmotic-Release Oral System methylphenidate (OROS(?) MPH) HCl (Concerta(?), Raritan, NJ) CII in children with ADHD. Method: Data were combined from two double-blind, randomized, placebo-controlled, cross-over, analog classroom studies in children (9-12 years) with ADHD. Participants received an individualized dose of placebo or OROS(?) MPH on two laboratory school days. Permanent Product Math Test and Swanson, Kotkin, Agler, M-Flynn, and Pelham scores were evaluated 0.5 hr before dosing and 1, 2, 4, 10, 11, and 12.5 hr post dose. Analysis used a repeated-measures mixed model. Results: Treatment effects were present at all postdose assessment points (p < .0001 for all comparisons, n = 139). Adverse events were similar to previous reports for OROS(?) MPH. Conclusion: A robust treatment effect occurred with OROS(?) MPH; onset was at 1 hr and persisted for at least 12.5 hr after dosing.  相似文献   
912.
Objective: Preclinical models, receptor localization, and genetic linkage data support the role of D4 receptors in the etiology of ADHD. This proof-of-concept study was designed to evaluate MK-0929, a selective D4 receptor antagonist as treatment for adult ADHD. Method: A randomized, double-blind, placebo-controlled, crossover study was conducted in adults with primary ADHD. The primary end point was changed from baseline in total score on the Adult ADHD Investigator Symptom Rating Scale following a 4-week treatment regimen. Additional measures included Clinical Global Impression-Severity Scale, Hospital Anxiety and Depression Scale, and Brown Attention Deficit Disorder Scale and D4 genotype analysis. Results: No statistically significant treatment differences were found between MK-0929 and placebo in any of the primary or secondary assessments. Conclusion: Results from this study suggest that blockade of the D4 receptor alone is not efficacious in the treatment of adult ADHD.  相似文献   
913.
914.
The present study is the first long-term longitudinal examination of the etiology of individual differences in language from early childhood through to adolescence. We applied a multivariate latent factor genetic model to longitudinal data from the Twins Early Development Study in order to (a) compare the magnitude of genetic and environmental influences on language skills in early childhood (2, 3 and 4 years), middle childhood (7, 9 and 10 years), and early adolescence (12 years); and (b) determine to what extent the same genetic and environmental factors underlie variation in language skills at these three stages of language development. We found that while shared environmental influences appear to be dominant (latent factor c2 = .74) in early language, with a smaller though significant role for genetic factors (latent factor a2 = .24), the pattern is reversed by middle childhood such that genetic influences are substantially more important (latent factor a2 = .57-.63 at 7, 9 and 10 years and .47-.57 at 12 years) and shared environmental influences less so (latent factor c2 = .31-.37 at 7, 9 and 10 years and .31-.32 at 12 years). The increase in the heritability of language skills between early and middle childhood appears to be due to new genetic factors that come into play at that transition. In contrast, genetic factors remain stable from middle childhood through to early adolescence, and account for the phenotypic continuity in language skills across these two stages.  相似文献   
915.
Previous behavioural research suggests that infants possess phonologically detailed representations of the vowels and consonants in familiar words. These tasks examine infants' sensitivity to mispronunciations of a target label in the presence of a target and distracter image. Sensitivity to the mispronunciation may, therefore, be contaminated by the degree of mismatch between the distracter label and the heard mispronounced label. Event-related potential (ERP) studies allow investigation of infants' sensitivity to the relationship between a heard label (correct or mispronounced) and the referent alone using single picture trials. ERPs also provide information about the timing of lexico-phonological activation in infant word recognition. The current study examined 14-month-olds' sensitivity to vowel mispronunciations of familiar words using ERP data from single picture trials. Infants were presented with familiar images followed by a correct pronunciation of its label, a vowel mispronunciation or a phonologically unrelated non-word. The results support and extend previous behavioural findings that 14-month-olds are sensitive to mispronunciations of the vowels in familiar words using an ERP task. We suggest that the presence of pictorial context reinforces infants' sensitivity to mispronunciations of words, and that mispronunciation sensitivity may rely on infants accessing the cross-modal associations between word forms and their meanings.  相似文献   
916.
Existing research on commuting stress has shown that it is affected by variables such as control, predictability, the duration of the commute and impedance. The present study investigates the impact of several factors on the stress that commuters experience and clarifies possible relations between variables. For the purpose of this study, an online questionnaire was completed by 363 commuters of the Vienna region. The relative strength of the relationship between predictors and commuting stress was determined by multiple regression analysis. Results suggest that control is the most powerful predictor of commuting stress, followed by the duration of the commute, predictability and impedance. Control significantly interacts with the duration of the commute and predictability. Based on these findings a research model is proposed, clearly depicting the moderating impact of the duration of the commute and incorporating a clear distinction between predictability and control.  相似文献   
917.
Research shows that harmonious and obsessive passion are positively and negatively linked to well-being respectively (e.g., Vallerand et al. in J Personal 75:505?C534, 2007; Psychol Sport Exerc 9:373?C392, 2008). The present study investigated the psychological mechanisms underlying the different impact of the two types of passion on well-being. A theoretical model involving passion, ruminations, flow experiences, and well-being was tested. Results showed that the more people have a harmonious passion, the more they tend to experience flow in their favorite activity, which in turn predicts higher well-being. Obsessive passion did not seem to be systematically linked to flow in the favorite activity. In contrast, the more people have an obsessive passion, the more they tend to ruminate about their passionate activity while engaging in another activity, which did not seem to be systematically the case for people with a harmonious passion. These ruminations are negatively related to flow experiences in the other activity, which are positively associated with well-being. Flow and ruminations thus seem to contribute to the understanding of the link between passion and well-being.  相似文献   
918.
This article analyzes the Utrecht Work Engagement Scale (UWES; Schaufeli et al. in J Happiness Stud 3:71?C92, 2002b) on a variety of levels. Study 1 critiques the method by which the original scale was developed, and analyzes a similar sample using both exploratory and, subsequently, confirmatory factor analyses. Study 2 uses three samples to explore the 17-item UWES-17, and the recent shorter version of the scale, the 9-item UWES-9. Factor structures and reliabilities of scores for both scale versions were examined for each sample. Although some cautions are warranted when using the UWES, this research leans toward supporting a multifactorial conceptualization of the construct. Preliminary construct validation of the use of the measures was also established via correlations with other pertinent constructs. Although research on the measure remains sparse, the UWES-9 holds promise as a parsimonious version of the UWES-17 that appears valid in use, appears to yield reliable scores in the samples herein, and also appears to capture the purported three-factor dimensionality of the engagement construct better than does the original UWES-17 version.  相似文献   
919.
Communal predators may often need to make especially intricate foraging decisions, as a predator's success may depend on the actions of its neighbours. Here,we consider the decisions made by Portia africana, a jumping spider (Salticidae) that preys on other spiders, including Oecobius amboseli (Oecobiidae), a small prey spider that lives under small sheets of silk (nests) on the walls of buildings. P. africana juveniles settle near oecobiid nests and then ambush oecobiids as they leave or enter the nest. Two or more P. africana juveniles sometimes settle at the same nest and, when an oecobiid is captured, the P. africana juveniles may share the meal. We investigated the joining decisions made by na?ve P. africana juveniles. Experiments were based on using lures (dead spiders positioned in lifelike posture) arranged in a series of 17 different scenes defined by the presence/absence of a nest, the lure types present and the configuration of the lures and the nest. Our findings imply that P. africana juveniles make remarkably precise predatory decisions, with the variables that matter including whether a nest is present, the identity of spiders inside and outside a nest and how spiders are positioned relative to each other and the nest.  相似文献   
920.
ObjectivesThe Super Six World Boxing Classic was conceived by Showtime Sports to feature the best six professional boxers in the super middleweight division (168 pounds) throughout a modified round robin tournament. The objective was to explore the adaptation and mal-adaptation processes of the tournament's original six tournament participants over time.DesignMedia data in the form of documentary episodes (n = 12 episodes, ~30 min each from the foregoing source were transcribed verbatim. Data included athletes' responses prior to their first bout and as each progressed or was eliminated. Boxers' post-bout explanations were also included.MethodThe original six contestants (mean age = 28.8 years at tournament start) from the tournament, with a record of 157 wins and 4 losses, were included within the project. Data were analyzed via thematic analysis (see Braun & Clarke, 2006).ResultsThe following themes were identified: (a) pre-conditions: moving into the tournament (subthemes: positive anticipation, uncertainty), (b) outcomes: moving through the tournament (subthemes: tournament progression, tournament regressions), and (c) consequences: moving out of the tournament (sub-themes: responses of the defeated, the king's adaptation).ConclusionsThis study highlights the adaptation processes of the six tournament contestants, demonstrating how one athlete adapted successfully and became champion through personal focus. The remaining athletes lost at least once, with pre-bout adaptation processes suggesting performance regression. These findings add to the adaptation literature, further contextualizing how adaptation meanings change and unfold over time.  相似文献   
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