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Delay Interval (delay + interval)
Selected AbstractsZolpidem and triazolam interact differentially with a delay interval on a digit-enter-and-recall taskHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 2 2001Craig R. Rush Abstract Zolpidem (AMBIEN®), an imidazopyridine, is now the most commonly prescribed hypnotic in the United States. Zolpidem is neuropharmacologically distinct from benzodiazepine hypnotics in that it binds with low affinity to ,5 -containing GABAA -receptor subtypes. Despite its unique benzodiazepine-receptor binding profile, the results of most of the published studies conducted with humans suggest that the absolute magnitude of impairment produced by zolpidem is comparable to that observed with benzodiazepine hypnotics like triazolam. The present study compared the acute effects of zolpidem (0, 7.5, 15 and 22.5,mg) and triazolam (0, 0.1875, 0.375 and 0.5625,mg) in 10 non-drug-abusing humans using a Digit-Enter-and-Recall task with varying delay intervals (0, 10 and 20,s). To more fully characterize the behavioral effects of zolpidem and triazolam, several other performance tasks and subject-rated drug-effect questionnaires were included. Zolpidem and triazolam impaired performance on the Digit-Enter-and-Recall task as a function of dose under all delay intervals. However, the dose-related effects of the drugs interacted differentially with the delay interval such that zolpidem produced significantly less impairment than triazolam following the longest delay (i.e., 20,s). Zolpidem and triazolam produced comparable dose-related impairment on the digit symbol substitution test (DSST), circular lights task, and picture recall/recognition task. Zolpidem and triazolam generally produced qualitatively and quantitatively similar subject-rated drug effects, although some between-drug differences were observed. Consistent with the pharmacokinetics of these drugs, the effects of zolpidem peaked sooner and were shorter in duration than those observed with triazolam. The results of this experiment suggest that zolpidem may have less potential than triazolam to impair recall, which may be due to differences between these compounds in terms of their benzodiazepine-receptor binding profile. The results of the present study are also concordant with previous studies that found that drugs that act at the GABAA -receptor complex can be differentiated based on their interaction with the delay interval on a Digit-Enter-and-Recall task. Copyright © 2001 John Wiley & Sons, Ltd. [source] A delay decomposition approach to delay-dependent stability for linear systems with time-varying delaysINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 17 2009Xian-Ming Zhang Abstract This paper is concerned with delay-dependent stability for linear systems with time-varying delays. By decomposing the delay interval into multiple equidistant subintervals, on which different Lyapunov functionals are chosen, and new Lyapunov-Krasvskii functionals are then constructed. Employing these new Lyapunov-Krasvskii functionals, some new delay-dependent stability criteria are established. The numerical examples show that the obtained results are less conservative than some existing ones in the literature. Copyright © 2009 John Wiley & Sons, Ltd. [source] Visual working memory of jungle crows (Corvus macrorhynchos) in operant delayed matching-to-sample,JAPANESE PSYCHOLOGICAL RESEARCH, Issue 3 2009KAZUHIRO GOTO Abstract We examined the capacity of visual working memory in three male jungle crows using an operant delayed matching-to-sample procedure. In the delayed matching-to-sample, each trial started with the presentation of a sample stimulus, followed by the presentation of comparison stimuli after a delay interval. The choice of the matching comparison was rewarded. Jungle crows showed a steady decline in proportion correct with increasing delay interval. The proportion correct was higher when the sample stimulus was the same in the preceding trial, suggesting that proactive interference prevented the birds from retrieving the memory successfully. The analysis of response time revealed that response time was faster in correct than incorrect trials when the matching performance was acquired. Furthermore, response time linearly increased as the delay interval increased. Response time may reflect the processing of scanning memory as well as the level of confidence in their choice when retrieving. [source] Same Beginnings, Different Stories: A Comparison of American and Chinese Children's NarrativesCHILD DEVELOPMENT, Issue 5 2000Qi Wang This study examined social, emotional, and cognitive characteristics of American and Chinese children's narratives. Twenty-four American and 26 Chinese 6-year-old children participated. Each child was interviewed individually twice with a 1-week delay interval. During the two interviews, children were asked to tell 11 stories prompted by pictures and standard verbal leads and to recount 7 emotional memories. Content analyses were performed on children's stories and memories. In line with predictions, findings indicated that compared with American children, Chinese children showed greater orientation toward social engagement, greater concern with moral correctness, greater concern with authority, a less autonomous orientation, more expressions of emotions, and more situational details in both their stories and memories. A few gender differences were found. Findings are discussed in terms of different value systems and early socialization practices in these two cultures. [source] Zolpidem and triazolam interact differentially with a delay interval on a digit-enter-and-recall taskHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 2 2001Craig R. Rush Abstract Zolpidem (AMBIEN®), an imidazopyridine, is now the most commonly prescribed hypnotic in the United States. Zolpidem is neuropharmacologically distinct from benzodiazepine hypnotics in that it binds with low affinity to ,5 -containing GABAA -receptor subtypes. Despite its unique benzodiazepine-receptor binding profile, the results of most of the published studies conducted with humans suggest that the absolute magnitude of impairment produced by zolpidem is comparable to that observed with benzodiazepine hypnotics like triazolam. The present study compared the acute effects of zolpidem (0, 7.5, 15 and 22.5,mg) and triazolam (0, 0.1875, 0.375 and 0.5625,mg) in 10 non-drug-abusing humans using a Digit-Enter-and-Recall task with varying delay intervals (0, 10 and 20,s). To more fully characterize the behavioral effects of zolpidem and triazolam, several other performance tasks and subject-rated drug-effect questionnaires were included. Zolpidem and triazolam impaired performance on the Digit-Enter-and-Recall task as a function of dose under all delay intervals. However, the dose-related effects of the drugs interacted differentially with the delay interval such that zolpidem produced significantly less impairment than triazolam following the longest delay (i.e., 20,s). Zolpidem and triazolam produced comparable dose-related impairment on the digit symbol substitution test (DSST), circular lights task, and picture recall/recognition task. Zolpidem and triazolam generally produced qualitatively and quantitatively similar subject-rated drug effects, although some between-drug differences were observed. Consistent with the pharmacokinetics of these drugs, the effects of zolpidem peaked sooner and were shorter in duration than those observed with triazolam. The results of this experiment suggest that zolpidem may have less potential than triazolam to impair recall, which may be due to differences between these compounds in terms of their benzodiazepine-receptor binding profile. The results of the present study are also concordant with previous studies that found that drugs that act at the GABAA -receptor complex can be differentiated based on their interaction with the delay interval on a Digit-Enter-and-Recall task. Copyright © 2001 John Wiley & Sons, Ltd. [source] The Importance of Ventricular Septal Morphology in the Effectiveness of Dual Chamber Pacing in Hypertrophic Obstructive CardiomyopathyPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2000PETKOW DIMITROW It has been reported that older patients with hypertrophic obstructive Cardiomyopathy (HOCM) benefited the most from dual chamber (DDD) pacing. Since in older patients the distribution of septal hypertrophy and left ventricular (LV) cavity shape differs from that in younger patients, we decided to study the efficacy of DDD pacing on the reduction of LV outflow tract (LVOT) gradient in different patterns of septal hypertrophy. We compared HOCM patients with nonreversed septal curvature, thus preserving the elliptical LV cavity contour (common in the elderly), (group I) versus patients with reversed septal curvature, deforming the LV cavity to a crescent shape (common in the young), (group II). Eighteen HOCM patients were studied (11 patients in group I and 7 patients in group II). After implantation of a DDD pacemaker, the LVOT gradient was measured using Doppler echocardiography at various programmed AV delay intervals to determine the maximal percentage decrease of LVOT gradient from baseline. The measurement was repeated after at least a 6-month follow-up (chronic DDD pacing). The baseline LVOT gradient was comparable between groups (79 ± 28 vs 81 ± 25 mmHg, P = 0.92). The LVOT gradient reduction at acute DDD pacing was significantly greater in group I than group II (61 ± 18% vs 23 ± 10%, P = 0.0001). This difference in favor of the patients from group I was maintained at midterm follow-up (69 ± 17% vs 40 ± 17% P = 0.0076). In conclusion, patients with normal septal curvature and preserved elliptical LV cavity shape had a greater reduction of LVOT gradient after DDD pacing than patients with reversed septal curvature deforming LV cavity. The proposed criterion assessing the septal curvature may be useful to predict the efficacy of DDD pacing in the reduction of LVOT gradient. [source] | |||||||||||||