A New Delay Connection for Long Short-Term Memory Networks.

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Wang, Jianyong; Zhang, Lei; Chen, Yuanyuan; Yi, Zhang

2017-12-17

Connections play a crucial role in neural network (NN) learning because they determine how information flows in NNs. Suitable connection mechanisms may extensively enlarge the learning capability and reduce the negative effect of gradient problems. In this paper, a new delay connection is proposed for Long Short-Term Memory (LSTM) unit to develop a more sophisticated recurrent unit, called Delay Connected LSTM (DCLSTM). The proposed delay connection brings two main merits to DCLSTM with introducing no extra parameters. First, it allows the output of the DCLSTM unit to maintain LSTM, which is absent in the LSTM unit. Second, the proposed delay connection helps to bridge the error signals to previous time steps and allows it to be back-propagated across several layers without vanishing too quickly. To evaluate the performance of the proposed delay connections, the DCLSTM model with and without peephole connections was compared with four state-of-the-art recurrent model on two sequence classification tasks. DCLSTM model outperformed the other models with higher accuracy and F1[Formula: see text]score. Furthermore, the networks with multiple stacked DCLSTM layers and the standard LSTM layer were evaluated on Penn Treebank (PTB) language modeling. The DCLSTM model achieved lower perplexity (PPL)/bit-per-character (BPC) than the standard LSTM model. The experiments demonstrate that the learning of the DCLSTM models is more stable and efficient.

Adaptive exponential synchronization of delayed neural networks with reaction-diffusion terms

International Nuclear Information System (INIS)

Sheng Li; Yang Huizhong; Lou Xuyang

2009-01-01

This paper presents an exponential synchronization scheme for a class of neural networks with time-varying and distributed delays and reaction-diffusion terms. An adaptive synchronization controller is derived to achieve the exponential synchronization of the drive-response structure of neural networks by using the Lyapunov stability theory. At the same time, the update laws of parameters are proposed to guarantee the synchronization of delayed neural networks with all parameters unknown. It is shown that the approaches developed here extend and improve the ideas presented in recent literatures.

Global exponential stability of BAM neural networks with time-varying delays and diffusion terms

International Nuclear Information System (INIS)

Wan Li; Zhou Qinghua

2007-01-01

The stability property of bidirectional associate memory (BAM) neural networks with time-varying delays and diffusion terms are considered. By using the method of variation parameter and inequality technique, the delay-independent sufficient conditions to guarantee the uniqueness and global exponential stability of the equilibrium solution of such networks are established

Global exponential stability of BAM neural networks with time-varying delays and diffusion terms

Science.gov (United States)

Wan, Li; Zhou, Qinghua

2007-11-01

The stability property of bidirectional associate memory (BAM) neural networks with time-varying delays and diffusion terms are considered. By using the method of variation parameter and inequality technique, the delay-independent sufficient conditions to guarantee the uniqueness and global exponential stability of the equilibrium solution of such networks are established.

Changes in the long-term delayed response of platinum self-powered detector with irradiation

International Nuclear Information System (INIS)

Parent, G.; Serdula, K.J.; Eng, P.

1989-01-01

Two long-term delayed response characteristics have been observed for platinum, Pt, detectors in the Gentilly-2 600 MW(e) CANDU PHWR reactor. The first effect is a dip in the signal two to three hours after a shutdown, due to the (n,beta) interactions of Mn-55 and Ni-64 which exist as impurities in the detector assembly. The second effect is an increase of the delayed fraction of the signal. The low neutron absorption cross-section of Pt-196 combined with the conversion of the Pt-194 and Pt-195 results in build-up of the Pt-196. The long half-lives associated with the beta-emission in the transmutation of Pt-196 to Hg-198 or Hg-199 give rise to the observed long-term delayed response

Delayed Dopamine Signaling of Energy Level Builds Appetitive Long-Term Memory in Drosophila

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Pierre-Yves Musso

2015-02-01

Full Text Available Sensory cues relevant to a food source, such as odors, can be associated with post-ingestion signals related either to food energetic value or toxicity. Despite numerous behavioral studies, a global understanding of the mechanisms underlying these long delay associations remains out of reach. Here, we demonstrate in Drosophila that the long-term association between an odor and a nutritious sugar depends on delayed post-ingestion signaling of energy level. We show at the neural circuit level that the activity of two pairs of dopaminergic neurons is necessary and sufficient to signal energy level to the olfactory memory center. Accordingly, we have identified in these dopaminergic neurons a delayed calcium trace that correlates with appetitive long-term memory formation. Altogether, these findings demonstrate that the Drosophila brain remembers food quality through a two-step mechanism that consists of the integration of olfactory and gustatory sensory information and then post-ingestion energetic value.

Delayed dopamine signaling of energy level builds appetitive long-term memory in Drosophila.

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Musso, Pierre-Yves; Tchenio, Paul; Preat, Thomas

2015-02-24

Sensory cues relevant to a food source, such as odors, can be associated with post-ingestion signals related either to food energetic value or toxicity. Despite numerous behavioral studies, a global understanding of the mechanisms underlying these long delay associations remains out of reach. Here, we demonstrate in Drosophila that the long-term association between an odor and a nutritious sugar depends on delayed post-ingestion signaling of energy level. We show at the neural circuit level that the activity of two pairs of dopaminergic neurons is necessary and sufficient to signal energy level to the olfactory memory center. Accordingly, we have identified in these dopaminergic neurons a delayed calcium trace that correlates with appetitive long-term memory formation. Altogether, these findings demonstrate that the Drosophila brain remembers food quality through a two-step mechanism that consists of the integration of olfactory and gustatory sensory information and then post-ingestion energetic value. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Withdrawal-Related Changes in Delay Discounting Predict Short-Term Smoking Abstinence.

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Miglin, Rickie; Kable, Joseph W; Bowers, Maureen E; Ashare, Rebecca L

2017-06-01

Impulsive decision making is associated with smoking behavior and reflects preferences for smaller, immediate rewards and intolerance of temporal delays. Nicotine withdrawal may alter impulsive decision making and time perception. However, little is known about whether withdrawal-related changes in decision making and time perception predict smoking relapse. Forty-five smokers (14 female) completed two laboratory sessions, one following 24-hour abstinence and one smoking-as-usual (order counterbalanced; biochemically verified abstinence). During each visit, participants completed measures of time perception, decision making (ie, discount rates), craving, and withdrawal. Following the second laboratory session, subjects underwent a well-validated model of short-term abstinence (quit week) with small monetary incentives for each day of biochemically confirmed abstinence. Smokers significantly overestimated time during abstinence, compared to smoking-as-usual (p = .021), but there were no abstinence effects on discount rates (p = .6). During the quit week, subjects were abstinent for 3.5 days (SD = 2.15) and smoked a total of 12.9 cigarettes (SD = 15.8). Importantly, higher discount rates (ie, preferences for immediate rewards) during abstinence (abstinence minus smoking difference score) predicted greater number of days abstinent (p = .01) and fewer cigarettes smoked during the quit week (p = .02). Withdrawal-related change in time reproduction did not predict relapse (p = .2). These data suggest that individuals who have a greater preference for immediate rewards during abstinence (vs. smoking-as-usual) may be more successful at maintaining short-term abstinence when provided with frequent (eg, daily) versus less frequent incentive schedules (eg, 1 month). Abstinence-induced changes in decision making may be important for identifying smokers who may benefit from interventions that incentivize abstinence such as contingency management (CM). The present results

On the form of the forgetting function: the effects of arithmetic and logarithmic distributions of delays.

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Sargisson, Rebecca J; White, K Geoffrey

2003-11-01

Forgetting functions with 18 delay intervals were generated for delayed matching-to-sample performance in pigeons. Delay interval variation was achieved by arranging five different sets of five delays across daily sessions. In different conditions, the delays were distributed in arithmetic or logarithmic series. There was no convincing evidence for different effects on discriminability of the distributions of different delays. The mean data were better fitted by some mathematical functions than by others, but the best-fitting functions depended on the distribution of delays. In further conditions with a fixed set of five delays, discriminability was higher with a logarithmic distribution of delays than with an arithmetic distribution. This result is consistent with the treatment of the forgetting function in terms of generalization decrement.

Acute and delayed deferoxamine treatment attenuates long-term sequelae after germinal matrix hemorrhage in neonatal rats.

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Klebe, Damon; Krafft, Paul R; Hoffmann, Clotilde; Lekic, Tim; Flores, Jerry J; Rolland, William; Zhang, John H

2014-08-01

This study investigated if acute and delayed deferoxamine treatment attenuates long-term sequelae after germinal matrix hemorrhage (GMH). Bacterial collagenase (0.3 U) was infused intraparenchymally into the right hemispheric ganglionic eminence in P7 rat pups to induce GMH. GMH animals received either deferoxamine or vehicle twice a day for 7 consecutive days. Deferoxamine administration was initiated at either 1 hour or 72 hours post-GMH. Long-term neurocognitive deficits and motor coordination were assessed using Morris water maze, rotarod, and foot fault tests between day 21 to 28 post-GMH. At 28 days post-GMH, brain morphology was assessed and extracellular matrix protein (fibronectin and vitronectin) expression was determined. Acute and delayed deferoxamine treatment improved long-term motor and cognitive function at 21 to 28 days post-GMH. Attenuated neurofunction was paralleled with improved overall brain morphology at 28 days post-GMH, reducing white matter loss, basal ganglia loss, posthemorrhagic ventricular dilation, and cortical loss. GMH resulted in significantly increased expression of fibronectin and vitronectin, which was reversed by acute and delayed deferoxamine treatment. Acute and delayed deferoxamine administration ameliorated long-term sequelae after GMH. © 2014 American Heart Association, Inc.

Comparative long-term trend analysis of daily weather conditions with daily pollen concentrations in Brussels, Belgium

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Bruffaerts, Nicolas; De Smedt, Tom; Delcloo, Andy; Simons, Koen; Hoebeke, Lucie; Verstraeten, Caroline; Van Nieuwenhuyse, An; Packeu, Ann; Hendrickx, Marijke

2018-03-01

A clear rise in seasonal and annual temperatures, a gradual increase of total radiation, and a relative trend of change in seasonal precipitation have been observed for the last four decades in Brussels (Belgium). These local modifications may have a direct and indirect public health impact by altering the timing and intensity of allergenic pollen seasons. In this study, we assessed the statistical correlations (Spearman's test) between pollen concentration and meteorological conditions by using long-term daily datasets of 11 pollen types (8 trees and 3 herbaceous plants) and 10 meteorological parameters observed in Brussels between 1982 and 2015. Furthermore, we analyzed the rate of change in the annual cycle of the same selected pollen types by the Mann-Kendall test. We revealed an overall trend of increase in daily airborne tree pollen (except for the European beech tree) and an overall trend of decrease in daily airborne pollen from herbaceous plants (except for Urticaceae). These results revealed an earlier onset of the flowering period for birch, oak, ash, plane, grasses, and Urticaceae. Finally, the rates of change in pollen annual cycles were shown to be associated with the rates of change in the annual cycles of several meteorological parameters such as temperature, radiation, humidity, and rainfall.

Comparative long-term trend analysis of daily weather conditions with daily pollen concentrations in Brussels, Belgium.

Science.gov (United States)

Bruffaerts, Nicolas; De Smedt, Tom; Delcloo, Andy; Simons, Koen; Hoebeke, Lucie; Verstraeten, Caroline; Van Nieuwenhuyse, An; Packeu, Ann; Hendrickx, Marijke

2018-03-01

A clear rise in seasonal and annual temperatures, a gradual increase of total radiation, and a relative trend of change in seasonal precipitation have been observed for the last four decades in Brussels (Belgium). These local modifications may have a direct and indirect public health impact by altering the timing and intensity of allergenic pollen seasons. In this study, we assessed the statistical correlations (Spearman's test) between pollen concentration and meteorological conditions by using long-term daily datasets of 11 pollen types (8 trees and 3 herbaceous plants) and 10 meteorological parameters observed in Brussels between 1982 and 2015. Furthermore, we analyzed the rate of change in the annual cycle of the same selected pollen types by the Mann-Kendall test. We revealed an overall trend of increase in daily airborne tree pollen (except for the European beech tree) and an overall trend of decrease in daily airborne pollen from herbaceous plants (except for Urticaceae). These results revealed an earlier onset of the flowering period for birch, oak, ash, plane, grasses, and Urticaceae. Finally, the rates of change in pollen annual cycles were shown to be associated with the rates of change in the annual cycles of several meteorological parameters such as temperature, radiation, humidity, and rainfall.

Four-hour delayed memory recall for stories: Theoretical and clinical implications of measuring accelerated long-term forgetting.

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Ladowsky-Brooks, Ricki L

2016-01-01

It has been noted that clinical neuropsychological assessment is "blind" to certain abnormalities of consolidation that occur beyond standard 30-min delay intervals. For example, normal forgetting at 30-min delays has been followed by enhanced forgetting at longer delays in temporal-lobe epilepsy, termed accelerated long-term forgetting (ALF). To evaluate whether ALF could be identified in the neuropsychological assessment of a small sample of examinees with head injuries or other neurological diagnoses (n = 42), a 4-hr delayed recall condition was added to the Logical Memory subtest of the Wechsler Memory Scale-Third Edition. A small percentage of examinees (5/42 or 11%), despite exhibiting unimpaired story recall immediately and after 30-min delays, showed increased forgetting when compared with the average retention of stories (M = 0.83, SD = 0.17) after a 4-hr delay. Three of these 5 examinees also had impaired scores on 20-min delayed recall of the California Verbal Learning Test-Second Edition (CVLT-II) and would have been identified as having memory impairment without an extended, 4-hr delayed recall. In fact, the highest correlation among memory indexes was between 4-hr delayed recall of stories and delayed recall of the CVLT-II word list (r = .59, p < .0001), suggesting different consolidation rates for relational and nonrelational material.

Delayed Dopamine Signaling of Energy Level Builds Appetitive Long-Term Memory in Drosophila

OpenAIRE

Pierre-Yves Musso; Paul Tchenio; Thomas Preat

2015-01-01

Sensory cues relevant to a food source, such as odors, can be associated with post-ingestion signals related either to food energetic value or toxicity. Despite numerous behavioral studies, a global understanding of the mechanisms underlying these long delay associations remains out of reach. Here, we demonstrate in Drosophila that the long-term association between an odor and a nutritious sugar depends on delayed post-ingestion signaling of energy level. We show at the neural circuit level t...

The Long-Term Outcome Comparison of Different Time-Delayed Kallikrein Treatments in a Mouse Cerebral Ischemic Model

Directory of Open Access Journals (Sweden)

Yaohui Ni

2018-01-01

Full Text Available Delayed administration of kallikrein after cerebral infarction can improve neurological function. However, the appropriate kallkrein treatment time after ischemic stroke has not been illuminated. In this study, we compared the long-term outcome among three kallikrein therapeutic regimens starting at different time points following mouse cerebral ischemia. Furthermore, the protective mechanisms involving neurogenesis, angiogenesis, and AKT-GSK3β-VEGF signaling pathway were analyzed. Human tissue kallikrein was injected through the tail vein daily starting at 8 h, 24 h, or 36 h after right middle cerebral artery occlusion (MCAO until the 28th day. Three therapeutic regimens all protected against neurological dysfunction, but kallikrein treatment starting at 8 h after MCAO had the best efficacy. Additionally, kallikrein treatment at 8 h after MCAO significantly enhanced cell proliferation including neural stem cell and induced differentiation of neural stem cell into mature neuron. Kallikrein treatment starting at 8 h also promoted more angiogenesis than other two treatment regimens, which was associated with AKT-GSK3β-VEGF signaling pathway. Thus, we confirm that three delayed kallikrein treatments provide protection against cerebral infarction and furthermore suggest that kallikrein treatment starting at 8 h had a better effect than that at 24 h and 36 h. These findings provide the experimental data contributing to better clinical application of exogenous kallikrein.

Environmental enrichment decreases asphyxia-induced neurobehavioral developmental delay in neonatal rats.

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Kiss, Peter; Vadasz, Gyongyver; Kiss-Illes, Blanka; Horvath, Gabor; Tamas, Andrea; Reglodi, Dora; Koppan, Miklos

2013-11-13

Perinatal asphyxia during delivery produces long-term disability and represents a major problem in neonatal and pediatric care. Numerous neuroprotective approaches have been described to decrease the effects of perinatal asphyxia. Enriched environment is a popular strategy to counteract nervous system injuries. The aim of the present study was to investigate whether enriched environment is able to decrease the asphyxia-induced neurobehavioral developmental delay in neonatal rats. Asphyxia was induced in ready-to-deliver mothers by removing the pups by caesarian section after 15 min of asphyxia. Somatic and neurobehavioral development was tested daily and motor coordination weekly. Our results show that rats undergoing perinatal asphyxia had a marked developmental delay and worse performance in motor coordination tests. However, pups kept in enriched environment showed a decrease in the developmental delay observed in control asphyctic pups. Rats growing up in enriched environment did not show decrease in weight gain after the first week and the delay in reflex appearance was not as marked as in control rats. In addition, the development of motor coordination was not as strikingly delayed as in the control group. Short-term neurofunctional outcome are known to correlate with long-term deficits. Our results thus show that enriched environment could be a powerful strategy to decrease the deleterious developmental effects of perinatal asphyxia.

Global exponential stability of impulsive fuzzy cellular neural networks with mixed delays and reaction-diffusion terms

International Nuclear Information System (INIS)

Wang Xiaohu; Xu Daoyi

2009-01-01

In this paper, the global exponential stability of impulsive fuzzy cellular neural networks with mixed delays and reaction-diffusion terms is considered. By establishing an integro-differential inequality with impulsive initial condition and using the properties of M-cone and eigenspace of the spectral radius of nonnegative matrices, several new sufficient conditions are obtained to ensure the global exponential stability of the equilibrium point for fuzzy cellular neural networks with delays and reaction-diffusion terms. These results extend and improve the earlier publications. Two examples are given to illustrate the efficiency of the obtained results.

Interval oscillation criteria for second-order forced impulsive delay differential equations with damping term.

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Thandapani, Ethiraju; Kannan, Manju; Pinelas, Sandra

2016-01-01

In this paper, we present some sufficient conditions for the oscillation of all solutions of a second order forced impulsive delay differential equation with damping term. Three factors-impulse, delay and damping that affect the interval qualitative properties of solutions of equations are taken into account together. The results obtained in this paper extend and generalize some of the the known results for forced impulsive differential equations. An example is provided to illustrate the main result.

Sleep deprivation accelerates delay-related loss of visual short-term memories without affecting precision.

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Wee, Natalie; Asplund, Christopher L; Chee, Michael W L

2013-06-01

Visual short-term memory (VSTM) is an important measure of information processing capacity and supports many higher-order cognitive processes. We examined how sleep deprivation (SD) and maintenance duration interact to influence the number and precision of items in VSTM using an experimental design that limits the contribution of lapses at encoding. For each trial, participants attempted to maintain the location and color of three stimuli over a delay. After a retention interval of either 1 or 10 seconds, participants reported the color of the item at the cued location by selecting it on a color wheel. The probability of reporting the probed item, the precision of report, and the probability of reporting a nonprobed item were determined using a mixture-modeling analysis. Participants were studied twice in counterbalanced order, once after a night of normal sleep and once following a night of sleep deprivation. Sleep laboratory. Nineteen healthy college age volunteers (seven females) with regular sleep patterns. Approximately 24 hours of total SD. SD selectively reduced the number of integrated representations that can be retrieved after a delay, while leaving the precision of object information in the stored representations intact. Delay interacted with SD to lower the rate of successful recall. Visual short-term memory is compromised during sleep deprivation, an effect compounded by delay. However, when memories are retrieved, they tend to be intact.

Psychological vulnerability to daily stressors in old age: Results of short-term longitudinal studies.

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Schilling, Oliver Karl; Diehl, Manfred

2015-08-01

A growing numbers of intensive longitudinal studies examine the short-term variability of behavior in response to daily stressors. Collectively, these studies address the vulnerability for stress-related emotional burden as assessed in terms of the intraindividual association between daily stressors and negative affect (NA). This article provides a brief overview of the relevant research on so-called affective reactivity to daily stressors and focuses on findings on development of age-related stressor reactivity across the adult lifespan. Two theoretical propositions have been put forward. Firstly, it has been postulated that aging should be associated with increased affective reactivity, i.e. it has been assumed that the vulnerability in terms of physiological stress reactivity increases across the adult life span and, thus, a higher stress-induced emotional reactivity should result with increasing age. Secondly, it has been argued that due to the continued development of emotional self-regulation skills, there should be an age-related decrease in stress reactivity and, hence, an increased resilience. Findings on age differences in NA reactivity to daily stressors, however, have been inconsistent. A possible explanation for the inconsistent findings may lie in the fact that the postulated dynamics of increased vulnerability or resilience imply different time-related reactions to stressors. In particular, the activation and effectiveness of emotional self-regulation strategies increase with increasing time intervals from the stressors. This leads to the conclusion that with increasing age the resilience for longer periods of stress and accumulated stress should increase. Results from our own research support this hypothesis, where older adults reacted to multiple stressors in a more adaptive way than younger adults.

Long-Term Anabolic Androgenic Steroid Use Is Associated with Increased Atrial Electromechanical Delay in Male Bodybuilders

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Mustafa Akçakoyun

2014-01-01

Full Text Available We investigated the effect of long-term supraphysiologic doses of anabolic androgenic steroids (AAS on atrial electromechanical delay (AEMD in male bodybuilders. We clearly demonstrated that long-term consumption of supraphysiologic doses of AAS is associated with higher values of inter- and intra-AEMD in healthy young bodybuilders.

Short-term total sleep deprivation alters delay-conditioned memory in the rat.

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Tripathi, Shweta; Jha, Sushil K

2016-06-01

Short-term sleep deprivation soon after training may impair memory consolidation. Also, a particular sleep stage or its components increase after learning some tasks, such as negative and positive reinforcement tasks, avoidance tasks, and spatial learning tasks, and so forth. It suggests that discrete memory types may require specific sleep stage or its components for their optimal processing. The classical conditioning paradigms are widely used to study learning and memory but the role of sleep in a complex conditioned learning is unclear. Here, we have investigated the effects of short-term sleep deprivation on the consolidation of delay-conditioned memory and the changes in sleep architecture after conditioning. Rats were trained for the delay-conditioned task (for conditioning, house-light [conditioned stimulus] was paired with fruit juice [unconditioned stimulus]). Animals were divided into 3 groups: (a) sleep deprived (SD); (b) nonsleep deprived (NSD); and (c) stress control (SC) groups. Two-way ANOVA revealed a significant interaction between groups and days (training and testing) during the conditioned stimulus-unconditioned stimulus presentation. Further, Tukey post hoc comparison revealed that the NSD and SC animals exhibited significant increase in performances during testing. The SD animals, however, performed significantly less during testing. Further, we observed that wakefulness and NREM sleep did not change after training and testing. Interestingly, REM sleep increased significantly on both days compared to baseline more specifically during the initial 4-hr time window after conditioning. Our results suggest that the consolidation of delay-conditioned memory is sleep-dependent and requires augmented REM sleep during an explicit time window soon after training. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The nature of delayed dream incorporation ('dream-lag effect'): Personally significant events persist, but not major daily activities or concerns.

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Eichenlaub, Jean-Baptiste; van Rijn, Elaine; Phelan, Mairéad; Ryder, Larnia; Gaskell, M Gareth; Lewis, Penelope A; P Walker, Matthew; Blagrove, Mark

2018-04-22

Incorporation of details from waking life events into rapid eye movement (REM) sleep dreams has been found to be highest on the 2 nights after, and then 5-7 nights after, the event. These are termed, respectively, the day-residue and dream-lag effects. This study is the first to categorize types of waking life experiences and compare their incorporation into dreams across multiple successive nights. Thirty-eight participants completed a daily diary each evening and a dream diary each morning for 14 days. In the daily diary, three categories of experiences were reported: major daily activities (MDAs), personally significant events (PSEs) and major concerns (MCs). After the 14-day period each participant identified the correspondence between items in their daily diaries and subsequent dream reports. The day-residue and dream-lag effects were found for the incorporation of PSEs into dreams (effect sizes of .33 and .27, respectively), but only for participants (n = 19) who had a below-median total number of correspondences between daily diary items and dream reports (termed "low-incorporators" as opposed to "high-incorporators"). Neither the day-residue or dream-lag effects were found for MDAs or MCs. This U-shaped timescale of incorporation of events from daily life into dreams has been proposed to reflect REM sleep-dependent memory consolidation, possibly related to emotional memory processing. This study had a larger sample size of dreams than any dream-lag study hitherto with trained participants. Coupled with previous successful replications, there is thus substantial evidence supporting the dream-lag effect and further explorations of its mechanism, including its neural underpinnings, are warranted. © 2018 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.

Comparison of primary and delayed primary closure in dirty abdominal wounds in terms of frequency of surgical site infection

International Nuclear Information System (INIS)

Aziz, O.B.A.; Ahmed, N.; Butt, M.W.U.D.; Saleem, M.R.

2013-01-01

Objective: Objective of this study was to compare primary and delayed primary wound closure for dirty abdominal wounds in terms of frequency of surgical site infection. Study Design: Randomized Controlled Trial. Place and Duration of Study: Combined Military Hospital, Multan. From 16 Sep 2010 to 15 Mar 2011. Patients and Methods: A total of 110 patients were randomly divided into two groups of 55 patients each using random numbers table. Abdominal wounds of one group were closed primarily and of other group were subjected to delayed primary wound closure. The wounds were then checked for surgical site infection for seven post operative days. Results: A higher frequency of surgical site infection was observed in primary closure group (27.3%) as compared to delayed primary closure group (9.1%) which was statistically significant (p=0.013). Conclusion: Delayed primary closure is superior to primary closure in dirty abdominal wounds in terms of frequency of surgical site infection. (author)

On the cost/delay tradeoff of wireless delay tolerant geographic routing

OpenAIRE

Tasiopoulos, Argyrios; Tsiaras, Christos; Toumpis, Stavros

2012-01-01

In Delay Tolerant Networks (DTNs), there is a fundamental tradeoff between the aggregate transport cost of a packet and the delay in its delivery. We study this tradeoff in the context of geographical routing in wireless DTNs.We ?rst specify the optimal cost/delay tradeoff, i.e., the tradeoff under optimal network operation, using a dynamic network construction termed the Cost/Delay Evolving Graph (C/DEG) and the Optimal Cost/Delay Curve (OC/DC), a function that gives the minimum possible agg...

Stochastic two-delay differential model of delayed visual feedback effects on postural dynamics.

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Boulet, Jason; Balasubramaniam, Ramesh; Daffertshofer, Andreas; Longtin, André

2010-01-28

We report on experiments and modelling involving the 'visuo-postural control loop' in the upright stance. We experimentally manipulated an artificial delay to the visual feedback during standing, presented at delays ranging from 0 to 1 s in increments of 250 ms. Using stochastic delay differential equations, we explicitly modelled the centre-of-pressure (COP) and centre-of-mass (COM) dynamics with two independent delay terms for vision and proprioception. A novel 'drifting fixed point' hypothesis was used to describe the fluctuations of the COM with the COP being modelled as a faster, corrective process of the COM. The model was in good agreement with the data in terms of probability density functions, power spectral densities, short- and long-term correlations (Hurst exponents) as well the critical time between the two ranges. This journal is © 2010 The Royal Society

[Effectiveness of new, once-daily 5-aminosalicylic acid in the treatment of ulcerative colitis].

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Lakatos, Péter László; Lakatos, László

2009-03-01

5-aminosalicylate (5-ASA) agents remain the mainstay treatment in ulcerative colitis (UC). A number of oral 5-ASA agents is commercially available, including azo-bond pro-drugs such as sulfasalazine, olsalazine and balsalazide, and delayed- and controlled-release forms of mesalazine. In addition, the effectiveness of oral therapy relies on good compliance, which may be adversely affected by frequent daily dosing and a large number of tablets. Furthermore, poor adherence has been shown to be an important barrier to successful management of patients with UC. Recently, new, once-daily formulations of mesalazine including the unique multi-matrix delivery system and mesalazine granules were proven to be efficacious in inducing and maintaining remission in mild-to-moderate UC, with a good safety profile comparable to that of other oral mesalazine formulations. In addition, they offer the advantage of low pill burden and may contribute to increased long-term compliance and treatment success in clinical practice and might potentially further contribute to a decline in the risk for UC-associated colon cancers. In this systematic review, the authors summarize the available literature on the short- and medium-term efficacy and safety of the new once-daily mesalazine formulations.

OceanSITES PIRATA daily in-situ data

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National Oceanic and Atmospheric Administration, Department of Commerce — This file contains daily real-time and delayed-mode in-situ data from one of the Tropical Atmosphere/Ocean (TAO)/TRITON, Pilot Research Moored Array in the Tropical...

Language familiarity effects in short-term memory: the role of output delay and long-term knowledge.

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Thorn, Annabel S C; Gathercole, Susan E; Frankish, Clive R

2002-10-01

Four experiments examined the origins of language familiarity effects in bilingual short-term recall. In Experiments 1A and 1B, bilingual adults were tested on serial recall and probed serial recall of words and nonwords in their first and second languages. A first-language advantage was obtained on both measures, indicating that the beneficial effects of language familiarity are not exclusively attributable to lesser output delay during overt recall. In Experiments 2A and 2B, the same group of bilinguals was tested on serial recall and serial recognition of word lists in both languages. Although a sizeable first-language advantage was obtained on the serial recall measure, recognition performance was comparable in the two languages. On the basis of these results it is suggested that language differences in bilingual immediate memory arise in large part as a consequence of the differential availability of language-specific long-term knowledge with which to support retrieval processes in serial recall.

Positive solutions of a three-point boundary-value problem for differential equations with damping and actively bounded delayed forcing term

Directory of Open Access Journals (Sweden)

George L. Karakostas

2006-08-01

Full Text Available We provide sufficient conditions for the existence of positive solutions of a three-point boundary value problem concerning a second order delay differential equation with damping and forcing term whose the delayed part is an actively bounded function, a meaning introduced in [19]. By writing the damping term as a difference of two factors one can extract more information on the solutions. (For instance, in an application, given in the last section, we can give the exact value of the norm of the solution.

Long-term (5 years), high daily dosage of dietary agmatine--evidence of safety: a case report.

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Gilad, Gad M; Gilad, Varda H

2014-11-01

There is presently a great interest in the therapeutic potential of agmatine, decarboxylated arginine, for various diseases. Recent clinical studies have already shown that oral agmatine sulfate given for up to 3 weeks provides a safe and, as compared with current therapeutics, more effective treatment for neuropathic pain. These studies have ushered in the use of dietary agmatine as a nutraceutical. However, in view of information paucity, assessment of long-term safety of oral agmatine treatment is now clearly required. The authors of this report undertook to assess their own health status during ongoing consumption of a high daily dosage of oral agmatine over a period of 4-5 years. A daily dose of 2.67 g agmatine sulfate was encapsulated in gelatin capsules; the regimen consists of six capsules daily, each containing 445 mg, three in the morning and three in the evening after meals. Clinical follow-up consists of periodic physical examinations and laboratory blood and urine analyses. All measurements thus far remain within normal values and good general health status is sustained throughout the study period, up to 5 years. This case study shows for the first time that the recommended high dosage of agmatine may be consumed for at least 5 years without evidence of any adverse effects. These initial findings are highly important as they provide significant evidence for the extended long-term safety of a high daily dosage of dietary agmatine--a cardinal advantage for its utility as a nutraceutical.

OceanSITES TAO daily in-situ data

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This file contains daily real-time and delayed-mode in-situ data from one of the flux reference mooring sites in the tropical oceans. Included in this file are sea...

OceanSITES KEO daily in-situ data

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This file contains daily real-time and delayed-mode in-situ data from the Kuroshio Extension Observatory (KEO) site nominally at 32.3N,144.6E, in the Kuroshio...

OceanSITES PAPA daily in-situ data

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This file contains daily real-time and delayed-mode in-situ data from station Papa at 50N,145W in the North Pacific. This taut-line mooring has been instrumented...

Long-term resolution of delayed onset hypoglossal nerve palsy following occipital condyle fracture: Case report and review of the literature

Directory of Open Access Journals (Sweden)

Sudhakar Vadivelu

2017-01-01

Full Text Available The authors present the case of a patient that demonstrates resolution of delayed onset hypoglossal nerve palsy (HNP subsequent to occipital condyle fracture following a motor vehicle accident. Decompression of the hypoglossal nerve and craniocervical fixation led to satisfactory long-term (>5 years outcome. There is a scarcity of literature in recognizing HNPs following trauma and a lack of pathophysiological understanding to both a delayed presentation and to resolution versus persistence. This is the first report demonstrating long-term resolution of hypoglossal nerve injury following trauma to the craniocervical junction.

Short-term effect of fine particulate air pollution on daily mortality: a case-crossover study in a tropical city, Kaohsiung, Taiwan.

Science.gov (United States)

Tsai, Shang-Shyue; Chen, Chih-Cheng; Yang, Chun-Yuh

2014-01-01

Many studies have examined the short-term effects of air pollution on frequency of daily mortality over the past two decades. However, information on the relationship between levels of fine particles (PM(2.5)) and daily mortality is relatively sparse due to limited availability of monitoring data. Further the results are inconsistent. This study was undertaken to determine whether there was an association between PM(2.5) levels and daily mortality rate in Kaohsiung, Taiwan, a large industrial city with a tropical climate. Daily mortality rate, air pollution parameters, and weather data for Kaohsiung were obtained for the period from 2006 through 2008. The relative risk of daily mortality occurrence was estimated using a time-stratified case-crossover approach, controlling for (1) weather variables, (2) day of the week, (3) seasonality, and (4) long-term time trends. For the single-pollutant model (without adjustment for other pollutants), no significant effects were found between PM(2.5) and frequency of daily mortality on warm days (≥25°C). On cool days, PM(2.5) showed significant correlation with increased risk of mortality rate for all causes and circulatory diseases in single-pollutant model. There was no indication of an association between PM(2.5) and deaths due to respiratory diseases. The relationship appeared to be stronger on cool days. This study provided evidence of associations between short-term exposure to PM(2.5) and elevated risk of death for all cause and circulatory diseases.

Airline Schedule Disruption Management. The impact of flight delays on connection loss

Directory of Open Access Journals (Sweden)

Rahil Hicham

2017-01-01

Full Text Available Air travel demand is important and many travellers choose to drive to larger airports instead of flying from a small airport for many reasons, especially availability of non-stop flights. Another reason is perceived reliability of service. Consultants have pointed to a large number of delays and cancellations as reasons for low passenger. However, the effect of these flight delays on actual travel times is less clear. Because connections are usually necessary when traveling from small airports, departure delays may lead to missed connections. In the case of a cancellation, need to wait several hours (often overnight for the next flight due to the small number of daily departures. This paper evaluate the impact of delays and cancellations on the profit earned through the seats captured on new opened routes. This aspect of decision-making comes in the form of multi-objective problem by testing the impact of a new opened route in terms of flight delays costs, financial gain and the quality of the service provided to a target customer. The NSGA-II algorithm is adopted to generate a front of Pareto-optimal compound of a number of optimal departure times to the new destination while ensuring the best fill rate, and a minimum flight delays. The experiences are based on the flights of the Royal Air Maroc Company on the Casablanca hub.

New delay-dependent absolute stability criteria for Lur'e systems with time-varying delay

Science.gov (United States)

Chen, Yonggang; Bi, Weiping; Li, Wenlin

2011-07-01

In this article, the absolute stability problem is investigated for Lur'e systems with time-varying delay and sector-bounded nonlinearity. By employing the delay fractioning idea, the new augmented Lyapunov functional is first constructed. Then, by introducing some slack matrices and by reserving the useful term when estimating the upper bound of the derivative of Lyapunov functional, the new delay-dependent absolute stability criteria are derived in terms of linear matrix inequalities. Several numerical examples are presented to show the effectiveness and the less conservativeness of the proposed method.

Chronic and Daily Stressors Along With Negative Affect Interact to Predict Daily Tiredness.

Science.gov (United States)

Hartsell, Elizabeth N; Neupert, Shevaun D

2017-11-01

The present study examines the within-person relationship of daily stressors and tiredness and whether this depends on daily negative affect and individual differences in chronic stress. One hundred sixteen older adult participants were recruited via Amazon's Mechanical Turk for a 9-day daily diary study. Daily tiredness, daily stressors, and negative affect were measured each day, and chronic stress was measured at baseline. Daily stressors, daily negative affect, and chronic stress interacted to predict daily tiredness. People with high chronic stress who experienced an increase in daily negative affect were the most reactive to daily stressors in terms of experiencing an increase in daily tiredness. We also found that people with low levels of chronic stress were the most reactive to daily stressors when they experienced low levels of daily negative affect. Our results highlight the need for individualized and contextualized approaches to combating daily tiredness in older adults.

Analytical applications for delayed neutrons

International Nuclear Information System (INIS)

Eccleston, G.W.

1983-01-01

Analytical formulations that describe the time dependence of neutron populations in nuclear materials contain delayed-neutron dependent terms. These terms are important because the delayed neutrons, even though their yields in fission are small, permit control of the fission chain reaction process. Analytical applications that use delayed neutrons range from simple problems that can be solved with the point reactor kinetics equations to complex problems that can only be solved with large codes that couple fluid calculations with the neutron dynamics. Reactor safety codes, such as SIMMER, model transients of the entire reactor core using coupled space-time neutronics and comprehensive thermal-fluid dynamics. Nondestructive delayed-neutron assay instruments are designed and modeled using a three-dimensional continuous-energy Monte Carlo code. Calculations on high-burnup spent fuels and other materials that contain a mix of uranium and plutonium isotopes require accurate and complete information on the delayed-neutron periods, yields, and energy spectra. A continuing need exists for delayed-neutron parameters for all the fissioning isotopes

The choice of sensitive skin layer responsible for aftereffects of daily irradiation of the skin

International Nuclear Information System (INIS)

Keirim-Markus, I.B.

1992-01-01

The choice of sensitive human skin layer manifesting in delayed period after daily irradiation of the human skin (stochastic and determined effects) was evaluated. It was established that delayed aftereffects of daily radiation of the skin manifested as epidem damages. This layer of papilla derma of 10-15 mg/cm 2 thick situated at the great part of body surface, 15 mg/cm 2 on dorsal side of hands and 40 mg/cm 2 on palms and pillows of the fingers. Sensitive layer of skin dosimeter for a control of daily irradiation of people must have the same geometry

Intranasal insulin to improve developmental delay in children with 22q13 deletion syndrome: an exploratory clinical trial.

Science.gov (United States)

Schmidt, H; Kern, W; Giese, R; Hallschmid, M; Enders, A

2009-04-01

The 22q13 deletion syndrome (Phelan-McDermid syndrome) is characterised by a global developmental delay, absent or delayed speech, generalised hypotonia, autistic behaviour and characteristic phenotypic features. Intranasal insulin has been shown to improve declarative memory in healthy adult subjects and in patients with Alzheimer disease. To assess if intranasal insulin is also able to improve the developmental delay in children with 22q13 deletion syndrome. We performed exploratory clinical trials in six children with 22q13 deletion syndrome who received intranasal insulin over a period of 1 year. Short-term (during the first 6 weeks) and long-term effects (after 12 months of treatment) on motor skills, cognitive functions, or autonomous functions, speech and communication, emotional state, social behaviour, behavioural disorders, independence in daily living and education were assessed. The children showed marked short-term improvements in gross and fine motor activities, cognitive functions and educational level. Positive long-term effects were found for fine and gross motor activities, nonverbal communication, cognitive functions and autonomy. Possible side effects were found in one patient who displayed changes in balance, extreme sensitivity to touch and general loss of interest. One patient complained of intermittent nose bleeding. We conclude that long-term administration of intranasal insulin may benefit motor development, cognitive functions and spontaneous activity in children with 22q13 deletion syndrome.

Use of new once-daily 5-aminosalicylic acid preparations in the treatment of ulcerative colitis: Is there anything new under the sun?

Science.gov (United States)

Lakatos, Peter Laszlo

2009-04-21

5-aminosalicylate (5-ASA) agents remain the mainstay treatment in ulcerative colitis (UC). A number of oral 5-ASA agents are commercially available, including azobond pro-drugs, as well as delayed- and controlled-release forms of mesalazine. However, poor adherence due to frequent daily dosing and a large number of tablets has been shown to be an important barrier to successful management of patients with UC. Recently, new, once-daily formulations of mesalazine, including the unique multi-matrix delivery system and mesalazine granules, were proven to be efficacious in inducing and maintaining remission in mild-to-moderate UC, with a good safety profile comparable to that of other oral mesalazine formulations. In addition, they offer the advantage of a low pill burden and might contribute to increased long-term compliance and treatment success in clinical practice. This editorial summarizes the available literature on the short- and medium-term efficacy and safety of the new once-daily mesalazine formulations.

Methods to estimate railway capacity and passenger delays

DEFF Research Database (Denmark)

Landex, Alex

that an evaluation of passenger delays obtained with simulation software (in this case RailSys) and the passenger delay model is comparable with the daily operation of the Copenhagen suburban railway network. Using a microscopic simulation model, the thesis demonstrates that it is possible to compare travel times...... of additional travel time. The differences between the different kinds of delay (train delays, passenger delays and scheduled waiting time) are illustrated through simple, but representative, case examples in CHAPTER 10. The examples demonstrate that 3rd generation passenger delay models are more realistic than...... depend on the given infrastructure and timetable and can result in longer travel times for trains and passengers. Furthermore, the thesis shows that the network effects can result in reduced capacity as some trains or train services can make it impossible to operate other planned/desired trains or train...

Prefrontocortical dopamine loss in rats delays long-term extinction of contextual conditioned fear, and reduces social interaction without affecting short-term social interaction memory.

Science.gov (United States)

Fernandez Espejo, Emilio

2003-03-01

Prefrontal dopamine loss delays extinction of cued fear conditioning responses, but its role in contextual fear conditioning has not been explored. Medial prefrontal lesions also enhance social interaction in rats, but the role of prefrontal dopamine loss on social interaction memory is not known. Besides, a role for subcortical accumbal dopamine on mnesic changes after prefrontal dopamine manipulation has been proposed but not explored. The objective was to study the involvement of dopaminergic neurotransmission in the medial prefrontal cortex (mPFC) and nucleus accumbens in two mnesic tasks: contextual fear conditioning and social interaction memory. For contextual fear conditioning, short- and long-term freezing responses after an electric shock were studied, as well as extinction retention. Regarding social interaction memory, the recognition of a juvenile, a very sensitive short-term memory test, was used. Dopamine loss was carried out by injection of 6-hydroxydopamine, and postmortem catecholamine levels were analyzed by high-performance liquid chromatography. Prefrontocortical dopamine loss (>76%) led to a reactive enhancement of accumbal dopamine content (ploss. In lesioned rats, long-term extinction of contextual fear conditioning was significantly delayed and extinction retention was impaired without changes in acquisition and short-term contextual fear conditioning and, on the other hand, acquisition and short-term social interaction memory were not affected, although time spent on social interaction was significantly reduced. Added dopamine loss in the nucleus accumbens (>76%) did not alter these behavioral changes. In summary, the results of the present study indicate that the dopaminergic network in the mPFC (but not in the nucleus accumbens) coordinates the normal long-term extinction of contextual fear conditioning responses without affecting their acquisition, and it is involved in time spent on social interaction, but not acquisition and short-term

Ethanol consumption and pineal melatonin daily profile in rats.

Science.gov (United States)

Peres, Rafael; do Amaral, Fernanda Gaspar; Madrigrano, Thiago Cardoso; Scialfa, Julieta Helena; Bordin, Silvana; Afeche, Solange Castro; Cipolla-Neto, José

2011-10-01

It is well known that melatonin participates in the regulation of many important physiological functions such as sleep-wakefulness cycle, motor coordination and neural plasticity, and cognition. However, as there are contradictory results regarding the melatonin production diurnal profile under alcohol consumption, the aim of this paper was to study the phenomenology and mechanisms of the putative modifications on the daily profile of melatonin production in rats submitted to chronic alcohol intake. The present results show that rats receiving 10% ethanol in drinking water for 35 days display an altered daily profile of melatonin production, with a phase delay and a reduction in the nocturnal peak. This can be partially explained by a loss of the daily rhythm and the 25% reduction in tryptophan hydroxylase activity and, mainly, by a phase delay in arylalkylamine N-acetyltransferase gene expression and a 70% reduction in its peak activity. Upstream in the melatonin synthesis pathway, the results showed that noradrenergic signaling is impaired as well, with a decrease in β1 and α1 adrenergic receptors' mRNA contents and in vitro sustained loss of noradrenergic-stimulated melatonin production by glands from alcohol-treated rats. Together, these results confirm the alterations in the daily melatonin profile of alcoholic rats and suggest the possible mechanisms for the observed melatonin synthesis modification. © 2011 The Authors, Addiction Biology © 2011 Society for the Study of Addiction.

Delay-Dependent Exponential Stability for Discrete-Time BAM Neural Networks with Time-Varying Delays

Directory of Open Access Journals (Sweden)

Yonggang Chen

2008-01-01

Full Text Available This paper considers the delay-dependent exponential stability for discrete-time BAM neural networks with time-varying delays. By constructing the new Lyapunov functional, the improved delay-dependent exponential stability criterion is derived in terms of linear matrix inequality (LMI. Moreover, in order to reduce the conservativeness, some slack matrices are introduced in this paper. Two numerical examples are presented to show the effectiveness and less conservativeness of the proposed method.

Effects of social instability stress in adolescence on long-term, not short-term, spatial memory performance.

Science.gov (United States)

Green, Matthew R; McCormick, Cheryl M

2013-11-01

There is evidence that exposure to stressors in adolescence leads to lasting deficits on hippocampal-dependent tasks, but whether medial prefrontal cortical function is also impaired is unknown. We previously found that rats exposed to social instability stress in adolescence (SS; daily 1h isolation and subsequent change of cage partner between postnatal days 30 and 45) had impaired memory performance on a Spatial Object Location test and in memory for fear conditioning context, tasks that depend on the integrity of the hippocampus. Here we investigated whether impaired performance would be evident after adolescent SS in male rats on a different test of hippocampal function, spatial learning and memory in the Morris water maze (MWM) and on a working memory task for which performance depends on the integrity of the medial prefrontal cortex, the Delayed Alternation task (DAT). During MWM testing, SS rats showed greater improvements in performance across trials within days compared to control (CTL) rats, but showed less retention of learning between days (48 h) compared to CTL rats. Similarly, SS rats had impaired long-term memory in the Spatial Object Location test after a long delay (240 min), but not after shorter delays (15 or 60 min) compared to CTL rats. No group differences were observed on the DAT, which assessed working memory across brief delays (5-90 s). Thus, deficits in memory performance after chronic social stress in adolescence may be limited to long-term memory. Copyright © 2013 Elsevier B.V. All rights reserved.

Bifurcation analysis of a delay reaction-diffusion malware propagation model with feedback control

Science.gov (United States)

Zhu, Linhe; Zhao, Hongyong; Wang, Xiaoming

2015-05-01

With the rapid development of network information technology, information networks security has become a very critical issue in our work and daily life. This paper attempts to develop a delay reaction-diffusion model with a state feedback controller to describe the process of malware propagation in mobile wireless sensor networks (MWSNs). By analyzing the stability and Hopf bifurcation, we show that the state feedback method can successfully be used to control unstable steady states or periodic oscillations. Moreover, formulas for determining the properties of the bifurcating periodic oscillations are derived by applying the normal form method and center manifold theorem. Finally, we conduct extensive simulations on large-scale MWSNs to evaluate the proposed model. Numerical evidences show that the linear term of the controller is enough to delay the onset of the Hopf bifurcation and the properties of the bifurcation can be regulated to achieve some desirable behaviors by choosing the appropriate higher terms of the controller. Furthermore, we obtain that the spatial-temporal dynamic characteristics of malware propagation are closely related to the rate constant for nodes leaving the infective class for recovered class and the mobile behavior of nodes.

Chronic daily headaches

Directory of Open Access Journals (Sweden)

Fayyaz Ahmed

2012-01-01

Full Text Available Chronic Daily Headache is a descriptive term that includes disorders with headaches on more days than not and affects 4% of the general population. The condition has a debilitating effect on individuals and society through direct cost to healthcare and indirectly to the economy in general. To successfully manage chronic daily headache syndromes it is important to exclude secondary causes with comprehensive history and relevant investigations; identify risk factors that predict its development and recognise its sub-types to appropriately manage the condition. Chronic migraine, chronic tension-type headache, new daily persistent headache and medication overuse headache accounts for the vast majority of chronic daily headaches. The scope of this article is to review the primary headache disorders. Secondary headaches are not discussed except medication overuse headache that often accompanies primary headache disorders. The article critically reviews the literature on the current understanding of daily headache disorders focusing in particular on recent developments in the treatment of frequent headaches.

Objectively Measured Daily Steps and Subsequent Long Term All-Cause Mortality: The Tasped Prospective Cohort Study.

Directory of Open Access Journals (Sweden)

Terence Dwyer

Full Text Available Self-reported physical activity has been inversely associated with mortality but the effect of objectively measured step activity on mortality has never been evaluated. The objective is to determine the prospective association of daily step activity on mortality among free-living adults.Cohort study of free-living adults residing in Tasmania, Australia between 2000 and 2005 who participated in one of three cohort studies (n = 2 576 total participants. Daily step activity by pedometer at baseline at a mean of 58.8 years of age, and for a subset, repeated monitoring was available 3.7 (SD 1.3 years later (n = 1 679. All-cause mortality (n = 219 deaths was ascertained by record-linkage to the Australian National Death Index; 90% of participants were followed-up over ten years, until June 2011. Higher daily step count at baseline was linearly associated with lower all-cause mortality (adjusted hazard ratio AHR, 0.94; 95% CI, 0.90 to 0.98 per 1 000 steps; P = 0.004. Risk was altered little by removing deaths occurring in the first two years. Increasing baseline daily steps from sedentary to 10 000 steps a day was associated with a 46% (95% CI, 18% to 65%; P = 0.004 lower risk of mortality in the decade of follow-up. In addition, those who increased their daily steps over the monitoring period had a substantial reduction in mortality risk, after adjusting for baseline daily step count (AHR, 0.39; 95% CI, 0.22 to 0.72; P = 0.002, or other factors (AHR, 0.38; 95% CI, 0.21-0.70; P = 0.002.Higher daily step count was linearly associated with subsequent long term mortality among free living adults. These data are the first to quantify mortality reductions using an objective measure of physical activity in a free living population. They strongly underscore the importance of physical inactivity as a major public health problem.

Information transfer via implicit encoding with delay time modulation in a time-delay system

Energy Technology Data Exchange (ETDEWEB)

Kye, Won-Ho, E-mail: whkye@kipo.go.kr [Korean Intellectual Property Office, Government Complex Daejeon Building 4, 189, Cheongsa-ro, Seo-gu, Daejeon 302-701 (Korea, Republic of)

2012-08-20

A new encoding scheme for information transfer with modulated delay time in a time-delay system is proposed. In the scheme, the message is implicitly encoded into the modulated delay time. The information transfer rate as a function of encoding redundancy in various noise scales is presented and it is analyzed that the implicit encoding scheme (IES) has stronger resistance against channel noise than the explicit encoding scheme (EES). In addition, its advantages in terms of secure communication and feasible applications are discussed. -- Highlights: ► We propose new encoding scheme with delay time modulation. ► The message is implicitly encoded with modulated delay time. ► The proposed scheme shows stronger resistance against channel noise.

Effect of the long-term care prevention project on the motor functions and daily life activities of the elderly.

Science.gov (United States)

Wada, Yoshihiro; Sakuraba, Keisyoku; Kubota, Atsushi

2015-01-01

[Purpose] The purpose of this study was to verify the effects of the long-term care prevention project and develop an effective program. [Subjects] A total of 81 elderly people (age, 79 ± 5.1 years; height, 149.2 ± 9.2 cm; weight, 54.2 ± 11.4 kg). [Methods] Grip, knee extension muscular strength, 10 m walking speed, and Timed Up and Go time were measured for evaluation of motor functions, and the "Locomo 25", a 25-question risk assessment questionnaire, was used as the judgment criterion for evaluation of daily life activities, with measurements being taken at the beginning of the project and after three months. [Results] In the motor functions evaluation, significant differences were observed in 10 m walking speed, Timed Up and Go time, and knee extension strength. In the daily life activities evaluation, scores for pain, rising movement, standing movement, indoor walking, outdoor walking, and fear of falling were significantly reduced. In addition, a significant correlation was also observed between motor functions and daily life activities. [Conclusion] The result of this study indicated that the long-term care prevention project is effective in maintaining or improving muscular strength and mitigating pain in the elderly and that it is an effective program for maintaining daily life activities. We were also able to show that it would be effective to develop programs with a low exercise intensity that can be performed on a continuing by the elderly.

Novel delay-distribution-dependent stability analysis for continuous-time recurrent neural networks with stochastic delay

International Nuclear Information System (INIS)

Wang Shen-Quan; Feng Jian; Zhao Qing

2012-01-01

In this paper, the problem of delay-distribution-dependent stability is investigated for continuous-time recurrent neural networks (CRNNs) with stochastic delay. Different from the common assumptions on time delays, it is assumed that the probability distribution of the delay taking values in some intervals is known a priori. By making full use of the information concerning the probability distribution of the delay and by using a tighter bounding technique (the reciprocally convex combination method), less conservative asymptotic mean-square stable sufficient conditions are derived in terms of linear matrix inequalities (LMIs). Two numerical examples show that our results are better than the existing ones. (general)

An approach estimating the short-term effect of NO2 on daily mortality in Spanish cities.

Science.gov (United States)

Linares, Cristina; Falcón, Isabel; Ortiz, Cristina; Díaz, Julio

2018-04-07

Road traffic is the most significant source of urban air pollution. PM 2.5 is the air pollutant whose health effects have been most closely studied, and is the variable most commonly used as a proxy indicator of exposure to air pollution, whereas evidence on NO 2 concentrations per se is still under study. In the case of Spain, there are no specific updated studies which calculate short-term NO 2 -related mortality. To quantify the relative risks (RRs) and attributable risks (ARs) of daily mortality associated with NO 2 concentrations recorded in Spain across the study period, 2000-2009; and to calculate the number of NO 2 -related deaths. We calculated daily mortality due to natural causes (ICD-10: A00 R99), circulatory causes (ICD-10: I00 I99) and respiratory causes (ICD-10: J00 J99) for each province across the period 2000-2009, using data supplied by the National Statistics Institute. Mean daily NO 2 concentrations in μg/m 3 for each provincial capital were furnished by the Ministry of Agriculture & Environment, along with the equivalent figures for the control pollutants (PM 10 ). To estimate RRs and ARs, we used generalised linear models with a Poisson link, controlling for maximum and minimum daily temperature, trend of the series, seasonalities, and the autoregressive nature of the series. A meta-analysis with random effects was used to estimate RRs and ARs nationwide. The overall RRs obtained for Spain, corresponding to increases of 10 μg/m 3 in NO 2 concentrations were 1.012 (95% CI: 1.010 1.014) for natural-cause mortality, 1.028 (95% CI: 1.019 1.037) for respiratory-cause mortality, and 1.016 (95% CI: 1.012 1.021) for circulatory-cause mortality. This amounted to an annual overall 6085 deaths (95% CI: 3288 9427) due to natural causes, 1031 (95% CI: 466 1585) due to respiratory causes, and 1978 (95% CI: 828 3197) due to circulatory causes. By virtue of the number of cities involved and the nature of the analysis performed, with quantification of the

The Impact of Short-Term Video Games on Performance among Children with Developmental Delays: A Randomized Controlled Trial

Science.gov (United States)

Hsieh, Ru-Lan; Lee, Wen-Chung; Lin, Jui-Hsiang

2016-01-01

This prospective, randomized controlled study investigated the effects of short-term interactive video game playing among children with developmental delays participating in traditional rehabilitation treatment at a rehabilitation clinic. One hundred and one boys and 46 girls with a mean age of 5.8 years (range: 3 to 12 years) were enrolled in this study. All patients were confirmed to suffer from developmental delays, and were participating in traditional rehabilitation treatment. Children participated in two periods of 4 weeks each, group A being offered intervention of eight 30-minute sessions of interactive video games in the first period, and group B in the second, in addition to the traditional rehabilitation treatment. The physical, psychosocial, and total health of the children was periodically assessed using the parent-reported Pediatric Quality of Life Inventory-Generic Core Scales (PedsQL); and the children’s upper extremity and physical function, transfer and basic mobility, sports and physical functioning, and global functioning were assessed using the Pediatric Outcomes Data Collection Instrument. Parental impact was evaluated using the PedsQL-Family Impact Module for family function, PedsQL-Health Satisfaction questionnaire for parents’ satisfaction with their children’s care and World Health Organization-Quality of Life-Brief Version for quality of life. Compared with the baseline, significant improvements of physical function were observed in both groups (5.6 ± 19.5, p = 0.013; 4.7 ± 13.8, p = 0.009) during the intervention periods. No significant improvement of psychosocial health, functional performance, or family impact was observed in children with developmental delays. Short-term interactive video game play in conjunction with traditional rehabilitation treatment improved the physical health of children with developmental delays. Trial Registration: ClinicalTrials.gov NCT02184715 PMID:26983099

The Impact of Short-Term Video Games on Performance among Children with Developmental Delays: A Randomized Controlled Trial.

Directory of Open Access Journals (Sweden)

Ru-Lan Hsieh

Full Text Available This prospective, randomized controlled study investigated the effects of short-term interactive video game playing among children with developmental delays participating in traditional rehabilitation treatment at a rehabilitation clinic. One hundred and one boys and 46 girls with a mean age of 5.8 years (range: 3 to 12 years were enrolled in this study. All patients were confirmed to suffer from developmental delays, and were participating in traditional rehabilitation treatment. Children participated in two periods of 4 weeks each, group A being offered intervention of eight 30-minute sessions of interactive video games in the first period, and group B in the second, in addition to the traditional rehabilitation treatment. The physical, psychosocial, and total health of the children was periodically assessed using the parent-reported Pediatric Quality of Life Inventory-Generic Core Scales (PedsQL; and the children's upper extremity and physical function, transfer and basic mobility, sports and physical functioning, and global functioning were assessed using the Pediatric Outcomes Data Collection Instrument. Parental impact was evaluated using the PedsQL-Family Impact Module for family function, PedsQL-Health Satisfaction questionnaire for parents' satisfaction with their children's care and World Health Organization-Quality of Life-Brief Version for quality of life. Compared with the baseline, significant improvements of physical function were observed in both groups (5.6 ± 19.5, p = 0.013; 4.7 ± 13.8, p = 0.009 during the intervention periods. No significant improvement of psychosocial health, functional performance, or family impact was observed in children with developmental delays. Short-term interactive video game play in conjunction with traditional rehabilitation treatment improved the physical health of children with developmental delays.ClinicalTrials.gov NCT02184715.

The Impact of Short-Term Video Games on Performance among Children with Developmental Delays: A Randomized Controlled Trial.

Science.gov (United States)

Hsieh, Ru-Lan; Lee, Wen-Chung; Lin, Jui-Hsiang

2016-01-01

This prospective, randomized controlled study investigated the effects of short-term interactive video game playing among children with developmental delays participating in traditional rehabilitation treatment at a rehabilitation clinic. One hundred and one boys and 46 girls with a mean age of 5.8 years (range: 3 to 12 years) were enrolled in this study. All patients were confirmed to suffer from developmental delays, and were participating in traditional rehabilitation treatment. Children participated in two periods of 4 weeks each, group A being offered intervention of eight 30-minute sessions of interactive video games in the first period, and group B in the second, in addition to the traditional rehabilitation treatment. The physical, psychosocial, and total health of the children was periodically assessed using the parent-reported Pediatric Quality of Life Inventory-Generic Core Scales (PedsQL); and the children's upper extremity and physical function, transfer and basic mobility, sports and physical functioning, and global functioning were assessed using the Pediatric Outcomes Data Collection Instrument. Parental impact was evaluated using the PedsQL-Family Impact Module for family function, PedsQL-Health Satisfaction questionnaire for parents' satisfaction with their children's care and World Health Organization-Quality of Life-Brief Version for quality of life. Compared with the baseline, significant improvements of physical function were observed in both groups (5.6 ± 19.5, p = 0.013; 4.7 ± 13.8, p = 0.009) during the intervention periods. No significant improvement of psychosocial health, functional performance, or family impact was observed in children with developmental delays. Short-term interactive video game play in conjunction with traditional rehabilitation treatment improved the physical health of children with developmental delays. ClinicalTrials.gov NCT02184715.

A novel delay-dependent criterion for delayed neural networks of neutral type

International Nuclear Information System (INIS)

Lee, S.M.; Kwon, O.M.; Park, Ju H.

2010-01-01

This Letter considers a robust stability analysis method for delayed neural networks of neutral type. By constructing a new Lyapunov functional, a novel delay-dependent criterion for the stability is derived in terms of LMIs (linear matrix inequalities). A less conservative stability criterion is derived by using nonlinear properties of the activation function of the neural networks. Two numerical examples are illustrated to show the effectiveness of the proposed method.

Global exponential stability of octonion-valued neural networks with leakage delay and mixed delays.

Science.gov (United States)

Popa, Călin-Adrian

2018-06-08

This paper discusses octonion-valued neural networks (OVNNs) with leakage delay, time-varying delays, and distributed delays, for which the states, weights, and activation functions belong to the normed division algebra of octonions. The octonion algebra is a nonassociative and noncommutative generalization of the complex and quaternion algebras, but does not belong to the category of Clifford algebras, which are associative. In order to avoid the nonassociativity of the octonion algebra and also the noncommutativity of the quaternion algebra, the Cayley-Dickson construction is used to decompose the OVNNs into 4 complex-valued systems. By using appropriate Lyapunov-Krasovskii functionals, with double and triple integral terms, the free weighting matrix method, and simple and double integral Jensen inequalities, delay-dependent criteria are established for the exponential stability of the considered OVNNs. The criteria are given in terms of complex-valued linear matrix inequalities, for two types of Lipschitz conditions which are assumed to be satisfied by the octonion-valued activation functions. Finally, two numerical examples illustrate the feasibility, effectiveness, and correctness of the theoretical results. Copyright © 2018 Elsevier Ltd. All rights reserved.

Short-term retention of pictures and words as a function of type of distraction and length of delay interval.

Science.gov (United States)

Pellegrino, J W; Siegel, A W; Dhawan, M

1976-01-01

Picture and word triads were tested in a Brown-Peterson short-term retention task at varying delay intervals (3, 10, or 30 sec) and under acoustic and simultaneous acoustic and visual distraction. Pictures were superior to words at all delay intervals under single acoustic distraction. Dual distraction consistently reduced picture retention while simultaneously facilitating word retention. The results were interpreted in terms of the dual coding hypothesis with modality-specific interference effects in the visual and acoustic processing systems. The differential effects of dual distraction were related to the introduction of visual interference and differential levels of functional acoustic interference across dual and single distraction tasks. The latter was supported by a constant 2/1 ratio in the backward counting rates of the acoustic vs. dual distraction tasks. The results further suggest that retention may not depend on total processing load of the distraction task, per se, but rather that processing load operates within modalities.

Leveraging delay discounting for health: Can time delays influence food choice?

Science.gov (United States)

Appelhans, Bradley M; French, Simone A; Olinger, Tamara; Bogucki, Michael; Janssen, Imke; Avery-Mamer, Elizabeth F; Powell, Lisa M

2018-03-15

Delay discounting, the tendency to choose smaller immediate rewards over larger delayed rewards, is theorized to promote consumption of immediately rewarding but unhealthy foods at the expense of long-term weight maintenance and nutritional health. An untested implication of delay discounting models of decision-making is that selectively delaying access to less healthy foods may promote selection of healthier (immediately available) alternatives, even if they may be less desirable. The current study tested this hypothesis by measuring healthy versus regular vending machine snack purchasing before and during the implementation of a 25-s time delay on the delivery of regular snacks. Purchasing was also examined under a $0.25 discount on healthy snacks, a $0.25 tax on regular snacks, and the combination of both pricing interventions with the 25-s time delay. Across 32,019 vending sales from three separate vending locations, the 25-s time delay increased healthy snack purchasing from 40.1% to 42.5%, which was comparable to the impact of a $0.25 discount (43.0%). Combining the delay and the discount had a roughly additive effect (46.0%). However, the strongest effects were seen under the $0.25 tax on regular snacks (53.7%) and the combination of the delay and the tax (50.2%). Intervention effects varied substantially between vending locations. Importantly, time delays did not harm overall vending sales or revenue, which is relevant to the real-world feasibility of this intervention. More investigation is needed to better understand how the impact of time delays on food choice varies across populations, evaluate the effects of time delays on beverage vending choices, and extend this approach to food choices in contexts other than vending machines. ClinicalTrials.gov, NCT02359916. Copyright © 2018 Elsevier Ltd. All rights reserved.

Short-term sleep disturbance-induced stress does not affect basal pain perception, but does delay postsurgical pain recovery

OpenAIRE

Wang, Po-Kai; Cao, Jing; Wang, Hongzhen; Liang, Lingli; Zhang, Jun; Lutz, Brianna Marie; Shieh, Kun-Ruey; Bekker, Alex; Tao, Yuan-Xiang

2015-01-01

Chronic sleep disturbance-induced stress is known to increase basal pain sensitivity. However, most surgical patients frequently report short-term sleep disturbance/deprivation during pre- and post-operation periods and have normal pain perception pre-surgery. Whether this short-term sleep disturbance affects postsurgical pain is elusive. We here reported that pre- or post-exposure to rapid eye movement sleep disturbance (REMSD) 6 h daily for 3 consecutive days did not alter basal responses t...

Virtual unit delay for digital frequency adaptive T/4 delay phase-locked loop system

DEFF Research Database (Denmark)

Yang, Yongheng; Zhou, Keliang; Blaabjerg, Frede

2016-01-01

/processor with a fixed sampling rate considering the cost and complexity, where the number of unit delays that have been adopted should be an integer. For instance, in conventional digital control systems, a single-phase T/4 Delay Phase-Locked Loop (PLL) system takes 50 unit delays (i.e., in a 50-Hz system...... Delay PLL system should be done in its implementation. This process will result in performance degradation in the digital control system, as the exactly required number of delays is not realized. Hence, in this paper, a Virtual Unit Delay (VUD) has been proposed to address such challenges to the digital......Digital micro-controllers/processors enable the cost-effective control of grid-connected power converter systems in terms of system monitoring, signal processing (e.g., grid synchronization), control (e.g., grid current and voltage control), etc. Normally, the control is implemented in a micro-controller...

A delay fractioning approach to global synchronization of delayed complex networks with stochastic disturbances

International Nuclear Information System (INIS)

Wang Yao; Wang Zidong; Liang Jinling

2008-01-01

In this Letter, the synchronization problem is investigated for a class of stochastic complex networks with time delays. By utilizing a new Lyapunov functional form based on the idea of 'delay fractioning', we employ the stochastic analysis techniques and the properties of Kronecker product to establish delay-dependent synchronization criteria that guarantee the globally asymptotically mean-square synchronization of the addressed delayed networks with stochastic disturbances. These sufficient conditions, which are formulated in terms of linear matrix inequalities (LMIs), can be solved efficiently by the LMI toolbox in Matlab. The main results are proved to be much less conservative and the conservatism could be reduced further as the number of delay fractioning gets bigger. A simulation example is exploited to demonstrate the advantage and applicability of the proposed result

Delay-range-dependent exponential H∞ synchronization of a class of delayed neural networks

International Nuclear Information System (INIS)

Karimi, Hamid Reza; Maass, Peter

2009-01-01

This article aims to present a multiple delayed state-feedback control design for exponential H ∞ synchronization problem of a class of delayed neural networks with multiple time-varying discrete delays. On the basis of the drive-response concept and by introducing a descriptor technique and using Lyapunov-Krasovskii functional, new delay-range-dependent sufficient conditions for exponential H ∞ synchronization of the drive-response structure of neural networks are driven in terms of linear matrix inequalities (LMIs). The explicit expression of the controller gain matrices are parameterized based on the solvability conditions such that the drive system and the response system can be exponentially synchronized. A numerical example is included to illustrate the applicability of the proposed design method.

Delay-Dependent Control for Networked Control Systems with Large Delays

Directory of Open Access Journals (Sweden)

Yilin Wang

2013-01-01

Full Text Available We consider the problems of robust stability and control for a class of networked control systems with long-time delays. Firstly, a nonlinear discrete time model with mode-dependent time delays is proposed by converting the uncertainty of time delay into the uncertainty of parameter matrices. We consider a probabilistic case where the system is switched among different subsystems, and the probability of each subsystem being active is defined as its occurrence probability. For a switched system with a known subsystem occurrence probabilities, we give a stochastic stability criterion in terms of linear matrix inequalities (LMIs. Then, we extend the results to a more practical case where the subsystem occurrence probabilities are uncertain. Finally, a simulation example is presented to show the efficacy of the proposed method.

Exponential Stability for Impulsive BAM Neural Networks with Time-Varying Delays and Reaction-Diffusion Terms

Directory of Open Access Journals (Sweden)

Qiankun Song

2007-06-01

Full Text Available Impulsive bidirectional associative memory neural network model with time-varying delays and reaction-diffusion terms is considered. Several sufficient conditions ensuring the existence, uniqueness, and global exponential stability of equilibrium point for the addressed neural network are derived by M-matrix theory, analytic methods, and inequality techniques. Moreover, the exponential convergence rate index is estimated, which depends on the system parameters. The obtained results in this paper are less restrictive than previously known criteria. Two examples are given to show the effectiveness of the obtained results.

Exponential Stability for Impulsive BAM Neural Networks with Time-Varying Delays and Reaction-Diffusion Terms

Directory of Open Access Journals (Sweden)

Cao Jinde

2007-01-01

Full Text Available Impulsive bidirectional associative memory neural network model with time-varying delays and reaction-diffusion terms is considered. Several sufficient conditions ensuring the existence, uniqueness, and global exponential stability of equilibrium point for the addressed neural network are derived by M-matrix theory, analytic methods, and inequality techniques. Moreover, the exponential convergence rate index is estimated, which depends on the system parameters. The obtained results in this paper are less restrictive than previously known criteria. Two examples are given to show the effectiveness of the obtained results.

Delayed Complications and Long-term Management of Sulfur Mustard Poisoning: Recent Advances by Iranian Researchers (Part І of ІІ

Directory of Open Access Journals (Sweden)

Emadodin Darchini-Maragheh

2018-03-01

Full Text Available Chemical warfare agents are the most brutal weapons among the weapons of mass destruction. Sulfur mustard (SM is a potent toxic alkylating agent known as “the King of the Battle Gases”. SM has been the most widely used chemical weapon during the wars. It was widely used in World War I. Thereafter, it was extensively employed by the Iraqi troops against the Iranian military personnel and even civilians in the border cities of Iran and Iraq in the period between 1983 and 1988. Long-term incapacitating properties, significant environmental persistence, lack of an effective antidote, and relative ease of manufacturing have kept SM a potential agent for both terrorist and military uses. Even 3 decades after SM exposure, numerous delayed complications among Iranian victims are still being reported by researchers. The most common delayed complications have been observed in the respiratory tracts of chemically injured Iranian war veterans. Also, skin lesions and eye disorders have been observed in most Iranian SM-exposed war veterans in the delayed phase of SM intoxication. Thus, extensive research has been conducted on Iranian war veterans during the past decades. Nevertheless, major gaps still continue to exist in the SM literature. Part І of this paper will discuss the delayed complications and manifestations of exposure to SM among Iranian victims of the Iran–Iraq conflict. Part ІІ, which will appear in the next issue of Iran J Med Sci, will discuss the long-term management and therapy of SM-exposed patients.

Stochastic nonlinear time series forecasting using time-delay reservoir computers: performance and universality.

Science.gov (United States)

Grigoryeva, Lyudmila; Henriques, Julie; Larger, Laurent; Ortega, Juan-Pablo

2014-07-01

Reservoir computing is a recently introduced machine learning paradigm that has already shown excellent performances in the processing of empirical data. We study a particular kind of reservoir computers called time-delay reservoirs that are constructed out of the sampling of the solution of a time-delay differential equation and show their good performance in the forecasting of the conditional covariances associated to multivariate discrete-time nonlinear stochastic processes of VEC-GARCH type as well as in the prediction of factual daily market realized volatilities computed with intraday quotes, using as training input daily log-return series of moderate size. We tackle some problems associated to the lack of task-universality for individually operating reservoirs and propose a solution based on the use of parallel arrays of time-delay reservoirs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Lag synchronization of chaotic systems with time-delayed linear ...

Indian Academy of Sciences (India)

delayed linear terms via impulsive control is investigated. Based on the stability theory of impulsive delayed differen- tial equations, some sufficient conditions are obtained guaranteeing the synchronized behaviours between two delayed chaotic ...

Delayed somatic effects following extended radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Slanina, J

1977-10-27

A group of 135 patients was investigated, who suffered from Hodgkin's disease with long-term remission following radiotherapy. By restricting the investigations to the patient group with long-term remission and correlative examinations, differentiation was made between exclusive or principal delayed radiation effects and delayed effects due to other factors. The study reports the most significant results obtained in the fields of catamnesis, laboratory diagnostics, hematology, pulmology, cardiology, thyroid function tests, neurology, andrology and dermatology. Due to the numerous detectable delayed effects the group of patients with long-term remission receives a special status. Although those effects are in no proportion to the deletary risks of an untreated Hodgkin's disease and though they are consequently tolerable in the present state of the therapeutic development, they must initiate the completion of the therapeutic concept including performance of radiotherapy and aftercare, because only then the risk for the patient provoked by these effects, which ranges beyond the malignity of this disease can be reduced or prevented.

Delay-Range-Dependent H∞ Control for Automatic Mooring Positioning System with Time-Varying Input Delay

Directory of Open Access Journals (Sweden)

Xiaoyu Su

2014-01-01

Full Text Available Aiming at the economy and security of the positioning system in semi-submersible platform, the paper presents a new scheme based on the mooring line switching strategy. Considering the input delay in switching process, H∞ control with time-varying input delay is designed to calculate the control forces to resist disturbing forces. In order to reduce the conservativeness, the information of the lower bound of delay is taken into account, and a Lyapunov function which contains the range of delay is constructed. Besides, the input constraint is considered to avoid breakage of mooring lines. The sufficient conditions for delay-range-dependent stabilization are derived in terms of LMI, and the controller is also obtained. The effectiveness of the proposed approach is illustrated by a realistic design example.

Epileptiform abnormalities predict delayed cerebral ischemia in subarachnoid hemorrhage.

Science.gov (United States)

Kim, J A; Rosenthal, E S; Biswal, S; Zafar, S; Shenoy, A V; O'Connor, K L; Bechek, S C; Valdery Moura, J; Shafi, M M; Patel, A B; Cash, S S; Westover, M B

2017-06-01

To identify whether abnormal neural activity, in the form of epileptiform discharges and rhythmic or periodic activity, which we term here ictal-interictal continuum abnormalities (IICAs), are associated with delayed cerebral ischemia (DCI). Retrospective analysis of continuous electroencephalography (cEEG) reports and medical records from 124 patients with moderate to severe grade subarachnoid hemorrhage (SAH). We identified daily occurrence of seizures and IICAs. Using survival analysis methods, we estimated the cumulative probability of IICA onset time for patients with and without delayed cerebral ischemia (DCI). Our data suggest the presence of IICAs indeed increases the risk of developing DCI, especially when they begin several days after the onset of SAH. We found that all IICA types except generalized rhythmic delta activity occur more commonly in patients who develop DCI. In particular, IICAs that begin later in hospitalization correlate with increased risk of DCI. IICAs represent a new marker for identifying early patients at increased risk for DCI. Moreover, IICAs might contribute mechanistically to DCI and therefore represent a new potential target for intervention to prevent secondary cerebral injury following SAH. These findings imply that IICAs may be a novel marker for predicting those at higher risk for DCI development. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Maintenance of heartburn relief after step-down from twice-daily proton pump inhibitor to once-daily dexlansoprazole modified release.

Science.gov (United States)

Fass, Ronnie; Inadomi, John; Han, Cong; Mody, Reema; O'Neil, Janet; Perez, M Claudia

2012-03-01

Many patients with gastroesophageal reflux disease (GERD) take a proton pump inhibitor (PPI) twice daily to control symptoms. Once-daily dexlansoprazole modified release (MR) has a dual-delayed release formulation, making it attractive for step-down management of patients whose symptoms are well controlled on twice-daily PPIs. We investigated whether step-down to once-daily dexlansoprazole controls heartburn in patients with GERD who were receiving twice-daily PPI therapy. Patients 18 years and older taking a twice-daily PPI for symptom control were enrolled (n = 178) in a single-blind, multicenter study; 163 patients completed the study and 142 patients met criteria for the efficacy analysis. During the 6-week screening and treatment periods, patients recorded the presence of heartburn symptoms twice daily in electronic diaries. Patients' heartburn was considered well controlled if they had an average of 1 symptom or fewer per week during the last 4 weeks of screening and treatment. After screening, qualified patients were switched to masked dexlansoprazole MR 30 mg and placebo for 6 weeks. The primary efficacy end point was the proportion of patients whose heartburn remained well controlled after step-down. GERD-related symptoms and quality of life (QOL) also were evaluated using the Patient Assessment of Upper Gastrointestinal Disorders Symptom Severity Index (PAGI-SYM) and the PAGI-QOL questionnaires, respectively. After step-down to once-daily dexlansoprazole MR 30 mg, heartburn remained well controlled in 88% of patients (125 of 142). These patients were able to maintain their GERD-related symptom severity and QOL, indicated by marginal changes in the PAGI-SYM and PAGI-QOL total and subscale scores, respectively. Most patients with GERD who take twice-daily PPI to control heartburn are able to successfully step down to once-daily dexlansoprazole 30 mg. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.

Simulation of activation and propagation delay during tripolar neural stimulation

NARCIS (Netherlands)

Goodall, E.V.; Goodall, Eleanor V.; Kosterman, L. Martin; Struijk, Johannes J.; Struijk, J.J.; Holsheimer, J.

1993-01-01

Computer simulations were perfonned to investigate the influence of stimulus amplitude on cathodal activation delay, propagation delay and blocking during stimulation with a bipolar cuff electrode. Activation and propagation delays were combined in a total delay term which was minimized between the

Structural changes in chromosomes of peripheral blood lymphocytes in monkeys subjected to long-term daily irradiation

International Nuclear Information System (INIS)

Kosichenko, L.P.

1976-01-01

During the period that lasted from 4 to 11 years after the cessation of the long-term daily gamma-irradiation the frequency of chromosome rearrangements in peripheral blood lymphocytes of monkeys exceeded the control level. The number of rearrangements did not change significantly with different total irradiation doses (from 826 to 3677r). The main type of structural chromosome rearrangements were symmetrical chromosome exchanges. Abnormal cell clones in peripheral lymphocytes in monkeys irradiated with low doses exhibited no selective advantages during the periods of investigation

Delay-Dependent Guaranteed Cost Control of an Interval System with Interval Time-Varying Delay

Directory of Open Access Journals (Sweden)

Xiao Min

2009-01-01

Full Text Available This paper concerns the problem of the delay-dependent robust stability and guaranteed cost control for an interval system with time-varying delay. The interval system with matrix factorization is provided and leads to less conservative conclusions than solving a square root. The time-varying delay is assumed to belong to an interval and the derivative of the interval time-varying delay is not a restriction, which allows a fast time-varying delay; also its applicability is broad. Based on the Lyapunov-Ktasovskii approach, a delay-dependent criterion for the existence of a state feedback controller, which guarantees the closed-loop system stability, the upper bound of cost function, and disturbance attenuation lever for all admissible uncertainties as well as out perturbation, is proposed in terms of linear matrix inequalities (LMIs. The criterion is derived by free weighting matrices that can reduce the conservatism. The effectiveness has been verified in a number example and the compute results are presented to validate the proposed design method.

The daily commute from work to home: examining employees' experiences in relation to their recovery status.

Science.gov (United States)

van Hooff, Madelon L M

2015-04-01

Sufficient recovery after daily effort expenditure at work is important to protect employee health and well-being. However, the role of commuting in the daily effort-recovery process is still not very well understood. The present study aimed to advance insight in this respect by examining if relaxation, detachment, mastery and stressful delays experienced during the commute from work to home affect employees' recovery status after returning home from work and at the end of the evening. Daily job demands were expected to moderate these effects. Serenity and (low) anxiety were included as indicators of employees' recovery status. Data were collected by means of a 5-day daily diary study (three measurements daily) among 76 participants from various industries. Multilevel analyses showed that relaxation was positively and stressful delays were negatively related to employees' recovery status after returning home from work but not to indicators of recovery at the end of the evening. For detachment, similar relations were found but only on days with high job demands. Mastery was not related to employees' recovery status. These findings enhance our insight in the daily effort-recovery cycle and underline the importance of promoting detachment (on demanding workdays) and relaxation on the way home from work. Copyright © 2013 John Wiley & Sons, Ltd.

A Good Short-term Outcome in Delayed Decompression of Cauda Equina Syndrome in Klebsiella pneumoniae Spinal Epidural Abscess: A Case Report

Directory of Open Access Journals (Sweden)

Hanifah J

2017-07-01

Full Text Available Spinal epidural abscess is a severe, generally pyogenic, infection of the epidural space of spinal cord or cauda equina. The swelling caused by the abscess leads to compression or vascular disruption of neurological structures that requires urgent surgical decompression to avoid significant permanent disability. We share a rare case of Klebsiella pneumoniae spinal epidural abscess secondary to haematogenous spread of previous lung infection that presented late at our centre with cauda equina syndrome that showed good short-term outcome in delayed decompression. A 50-year old female presented with one-week history of persistent low back pain with progressively worsening bilateral lower limb weakness for seven days and urinary retention associated with saddle anesthesia of 2-day duration. Magnetic resonance imaging with contrast of the lumbo-sacral region showed an intramuscular collection of abscess at left gluteus maximus and left multifidus muscle with a L3-L5 posteriorly placed extradural lesion enhancing peripherally on contrast, suggestive of epidural abscess that compressed the cauda equina. The pus was drained using the posterior lumbar approach. Tissue and pus culture revealed Klebsiella pneumoniae, suggestive of bacterial infection. The patient made immediate improvement of muscle power over bilateral lower limbs postoperative followed by ability to control micturition and defecation in the 4th post-operative day. A good short-term outcome in delayed decompression of cauda equine syndrome is extremely rare. Aggressive surgical decompression combined with antibiotic therapy led to good short-term outcome in this patient despite delayed decompression of more than 48 hours.

Synchronization of nonidentical chaotic neural networks with leakage delay and mixed time-varying delays

Directory of Open Access Journals (Sweden)

Cao Jinde

2011-01-01

Full Text Available Abstract In this paper, an integral sliding mode control approach is presented to investigate synchronization of nonidentical chaotic neural networks with discrete and distributed time-varying delays as well as leakage delay. By considering a proper sliding surface and constructing Lyapunov-Krasovskii functional, as well as employing a combination of the free-weighting matrix method, Newton-Leibniz formulation and inequality technique, a sliding mode controller is designed to achieve the asymptotical synchronization of the addressed nonidentical neural networks. Moreover, a sliding mode control law is also synthesized to guarantee the reachability of the specified sliding surface. The provided conditions are expressed in terms of linear matrix inequalities, and are dependent on the discrete and distributed time delays as well as leakage delay. A simulation example is given to verify the theoretical results.

Effects by daily long term provision of ghrelin to unselected weight-losing cancer patients: a randomized double-blind study.

Science.gov (United States)

Lundholm, Kent; Gunnebo, Lena; Körner, Ulla; Iresjö, Britt-Marie; Engström, Cecilia; Hyltander, Anders; Smedh, Ulrika; Bosaeus, Ingvar

2010-04-15

The short-term provision of ghrelin to patients with cancer indicates that there may be benefits from long-term provision of ghrelin for the palliative treatment of weight-losing cancer patients. This hypothesis was evaluated in a randomized, double-blind, phase 2 study. Weight-losing cancer patients with solid gastrointestinal tumors were randomized to receive either high-dose ghrelin treatment (13 microg/kg daily; n = 17 patients) or low-dose ghrelin treatment (0.7 microg/kg daily; n = 14 patients) for 8 weeks as a once-daily, subcutaneous injections. Appetite was scored on a visual analog scale; and food intake, resting energy expenditure, and body composition (dual x-ray absorpitometry) were measured before the start of treatment and during follow-up. Serum levels of ghrelin, insulin, insulin-like growth factor 1, growth hormone (GH), triglycerides, free fatty acids, and glucose were measured. Health-related quality of life, anxiety, and depression were assessed by using standardized methods (the 36-item Short Form Health Survey and the Hospital Anxiety and Depression Scale). Physical activity, rest, and sleep were measured by using a multisensor body monitor. Treatment groups were comparable at inclusion. Appetite scores were increased significantly by high-dose ghrelin analyzed both on an intent-to-treat basis and according to the protocol. High-dose ghrelin reduced the loss of whole body fat (P losing cancer patients with solid tumors supports host metabolism, improves appetite, and attenuates catabolism. (c) 2010 American Cancer Society.

'Delayed discharges and boarders': a 2-year study of the relationship between patients experiencing delayed discharges from an acute hospital and boarding of admitted patients in a crowded ED.

Science.gov (United States)

Mustafa, Farah; Gilligan, Peadar; Obu, Deborah; O'Kelly, Patrick; O'Hea, Eimear; Lloyd, Catherine; Kelada, Sherif; Heffernan, Attracta; Houlihan, Patricia

2016-09-01

Many believe that hospital crowding manifesting in the ED with the boarding of admitted patients is a result of significant numbers of acute hospital beds being occupied by patients awaiting discharge to nursing homes, step-down facilities or home with or without additional support. This observational study was performed to establish the actual relationship between boarders in the ED and patients experiencing delayed discharge. Data relating to the number of patients in the ED and their points in their patient pathway were entered into a logbook on a daily basis by the most senior doctor on duty. 630 days of observations of patients boarded in the ED were compared with the number of inpatients with delayed discharges, obtained from the hospital information system, to see if large numbers of inpatients with delayed discharges are associated with crowding in the ED. Two years of data showed an annual ED census of more than 47 000, with a daily mean ED admission rate of 29.85 patients and a daily mean ED boarding figure of 29 patients. A mean of 15.4% of the 823 hospital beds was occupied by patients with delayed discharges, and the hospital ran at, or near, full capacity (99%-105%) all the time. Results obtained highlighted a statistically significant relationship between delayed discharges in the hospital and ED crowding as a result of boarders (p value<0.001, with a regression coefficient of 0.16, 95% CI 0.12 to 0.20). The study also showed that the number of boarders was related to the number of ED admissions in the preceding 24 hours (p=0.036, with a regression coefficient of 0.14, 95% CI 0.05 to 0.28). Delayed hospital discharges significantly contribute to crowding in the ED. Healthcare systems should target timely discharge of inpatients experiencing delayed discharge in an urgent and efficient manner to improve timely access to acute hospital beds for patients requiring emergency admission. Published by the BMJ Publishing Group Limited. For permission

Lag synchronization of chaotic systems with time-delayed linear

Indian Academy of Sciences (India)

In this paper, the lag synchronization of chaotic systems with time-delayed linear terms via impulsive control is investigated. Based on the stability theory of impulsive delayed differential equations, some sufficient conditions are obtained guaranteeing the synchronized behaviours between two delayed chaotic systems.

Time-delayed autosynchronous swarm control.

Science.gov (United States)

Biggs, James D; Bennet, Derek J; Dadzie, S Kokou

2012-01-01

In this paper a general Morse potential model of self-propelling particles is considered in the presence of a time-delayed term and a spring potential. It is shown that the emergent swarm behavior is dependent on the delay term and weights of the time-delayed function, which can be set to induce a stationary swarm, a rotating swarm with uniform translation, and a rotating swarm with a stationary center of mass. An analysis of the mean field equations shows that without a spring potential the motion of the center of mass is determined explicitly by a multivalued function. For a nonzero spring potential the swarm converges to a vortex formation about a stationary center of mass, except at discrete bifurcation points where the center of mass will periodically trace an ellipse. The analytical results defining the behavior of the center of mass are shown to correspond with the numerical swarm simulations.

The dynamics of second-order equations with delayed feedback and a large coefficient of delayed control

Science.gov (United States)

Kashchenko, Sergey A.

2016-12-01

The dynamics of second-order equations with nonlinear delayed feedback and a large coefficient of a delayed equation is investigated using asymptotic methods. Based on special methods of quasi-normal forms, a new construction is elaborated for obtaining the main terms of asymptotic expansions of asymptotic residual solutions. It is shown that the dynamical properties of the above equations are determined mostly by the behavior of the solutions of some special families of parabolic boundary value problems. A comparative analysis of the dynamics of equations with the delayed feedback of three types is carried out.

Mittag-Leffler synchronization of fractional neural networks with time-varying delays and reaction-diffusion terms using impulsive and linear controllers.

Science.gov (United States)

Stamova, Ivanka; Stamov, Gani

2017-12-01

In this paper, we propose a fractional-order neural network system with time-varying delays and reaction-diffusion terms. We first develop a new Mittag-Leffler synchronization strategy for the controlled nodes via impulsive controllers. Using the fractional Lyapunov method sufficient conditions are given. We also study the global Mittag-Leffler synchronization of two identical fractional impulsive reaction-diffusion neural networks using linear controllers, which was an open problem even for integer-order models. Since the Mittag-Leffler stability notion is a generalization of the exponential stability concept for fractional-order systems, our results extend and improve the exponential impulsive control theory of neural network system with time-varying delays and reaction-diffusion terms to the fractional-order case. The fractional-order derivatives allow us to model the long-term memory in the neural networks, and thus the present research provides with a conceptually straightforward mathematical representation of rather complex processes. Illustrative examples are presented to show the validity of the obtained results. We show that by means of appropriate impulsive controllers we can realize the stability goal and to control the qualitative behavior of the states. An image encryption scheme is extended using fractional derivatives. Copyright © 2017 Elsevier Ltd. All rights reserved.

Daily acclimation handling does not affect hippocampal long-term potentiation or cause chronic sleep deprivation in mice.

Science.gov (United States)

Vecsey, Christopher G; Wimmer, Mathieu E J; Havekes, Robbert; Park, Alan J; Perron, Isaac J; Meerlo, Peter; Abel, Ted

2013-04-01

Gentle handling is commonly used to perform brief sleep deprivation in rodents. It was recently reported that daily acclimation handling, which is often used before behavioral assays, causes alterations in sleep, stress, and levels of N-methyl-D-aspartate receptor subunits prior to the actual period of sleep deprivation. It was therefore suggested that acclimation handling could mediate some of the observed effects of subsequent sleep deprivation. Here, we examine whether acclimation handling, performed as in our sleep deprivation studies, alters sleep/wake behavior, stress, or forms of hippocampal synaptic plasticity that are impaired by sleep deprivation. Adult C57BL/6J mice were either handled daily for 6 days or were left undisturbed in their home cages. On the day after the 6(th) day of handling, long-term potentiation (LTP) was induced in hippocampal slices with spaced four-train stimulation, which we previously demonstrated to be impaired by brief sleep deprivation. Basal synaptic properties were also assessed. In three other sets of animals, activity monitoring, polysomnography, and stress hormone measurements were performed during the 6 days of handling. Daily gentle handling alone does not alter LTP, rest/activity patterns, or sleep/wake architecture. Handling initially induces a minimal stress response, but by the 6(th) day, stress hormone levels are unaltered by handling. It is possible to handle mice daily to accustom them to the researcher without causing alterations in sleep, stress, or synaptic plasticity in the hippocampus. Therefore, effects of acclimation handling cannot explain the impairments in signaling mechanisms, synaptic plasticity, and memory that result from brief sleep deprivation.

Improved Delay-Dependent Robust Stability Criteria for a Class of Uncertain Neutral Type Lur’e Systems with Discrete and Distributed Delays

Directory of Open Access Journals (Sweden)

Kaibo Shi

2014-01-01

Full Text Available This paper is concerned with the problem of delay-dependent robust stability analysis for a class of uncertain neutral type Lur’e systems with mixed time-varying delays. The system has not only time-varying uncertainties and sector-bounded nonlinearity, but also discrete and distributed delays, which has never been discussed in the previous literature. Firstly, by employing one effective mathematical technique, some less conservative delay-dependent stability results are established without employing the bounding technique and the mode transformation approach. Secondly, by constructing an appropriate new type of Lyapunov-Krasovskii functional with triple terms, improved delay-dependent stability criteria in terms of linear matrix inequalities (LMIs derived in this paper are much brief and valid. Furthermore, both nonlinearities located in finite sector and infinite one have been also fully taken into account. Finally, three numerical examples are presented to illustrate lesser conservatism and the advantage of the proposed main results.

Delay-Dependent Guaranteed Cost H∞ Control of an Interval System with Interval Time-Varying Delay

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Zhongke Shi

2009-01-01

Full Text Available This paper concerns the problem of the delay-dependent robust stability and guaranteed cost H∞ control for an interval system with time-varying delay. The interval system with matrix factorization is provided and leads to less conservative conclusions than solving a square root. The time-varying delay is assumed to belong to an interval and the derivative of the interval time-varying delay is not a restriction, which allows a fast time-varying delay; also its applicability is broad. Based on the Lyapunov-Ktasovskii approach, a delay-dependent criterion for the existence of a state feedback controller, which guarantees the closed-loop system stability, the upper bound of cost function, and disturbance attenuation lever for all admissible uncertainties as well as out perturbation, is proposed in terms of linear matrix inequalities (LMIs. The criterion is derived by free weighting matrices that can reduce the conservatism. The effectiveness has been verified in a number example and the compute results are presented to validate the proposed design method.

Seasonal and Daily Variations of Subsurface Velocity Revealed by the Air-gun Source in Binchuan, Yunnan, China

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Luan, Y.; Yang, H.; Wang, B.

2017-12-01

We derive temporal variations of subsurface structure using a large-volume air-gun source excited in Binchuan, Yunnan, southwest China, the first transmitting seismic station that can generate high-quality repeating waveforms. The data were collected between January 2013 and December 2015 that were recorded by 40 stations within 150 km, including permanent and newly deployed air-gun array stations. Firstly, we conduct cluster analysis using the waveforms at the nearest station and find the clustering result is not only governed by the water level of the reservoir, but also has seasonal variations. Furthermore, we use the records of the nearest station to approximate the source time functions and then retrieve empirical Green's functions (EGF) by deconvolution. Then we obtain travel time difference by comparing the EGF. The travel time difference exhibits clear seasonal variation, and the pattern correlates the best with surface air temperature. The increasing temperature coincides with increasing delay time i.e. decreasing seismic velocity. We interpret the observed seasonal variation of subsurface velocity is partly caused by thermo-elastic strain. However, our calculated thermo-elastic strain is only half in amplitude of the observed strain, indicating other factors such as precipitation and ground water level may play a role in the subsurface changes. Moreover, we derive the daily variation of subsurface velocity in December 2015 when air-gun shots were made in every hour. The delay time clearly correlates with the barometric pressure change and the tidal strain. Here we demonstrate that both long-term (seasonal) and short-term (daily) structural variations can be derived using the newly constructed active source, which is a powerful tool to advance our understanding of rheological properties of the crust as well as well processes associated with earthquakes and other natural hazards.

Improved Criteria on Delay-Dependent Stability for Discrete-Time Neural Networks with Interval Time-Varying Delays

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O. M. Kwon

2012-01-01

Full Text Available The purpose of this paper is to investigate the delay-dependent stability analysis for discrete-time neural networks with interval time-varying delays. Based on Lyapunov method, improved delay-dependent criteria for the stability of the networks are derived in terms of linear matrix inequalities (LMIs by constructing a suitable Lyapunov-Krasovskii functional and utilizing reciprocally convex approach. Also, a new activation condition which has not been considered in the literature is proposed and utilized for derivation of stability criteria. Two numerical examples are given to illustrate the effectiveness of the proposed method.

New Delay-Dependent Stability Criteria for Uncertain Neutral Systems with Mixed Time-Varying Delays and Nonlinear Perturbations

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Hamid Reza Karimi

2009-01-01

Full Text Available The problem of stability analysis for a class of neutral systems with mixed time-varying neutral, discrete and distributed delays and nonlinear parameter perturbations is addressed. By introducing a novel Lyapunov-Krasovskii functional and combining the descriptor model transformation, the Leibniz-Newton formula, some free-weighting matrices, and a suitable change of variables, new sufficient conditions are established for the stability of the considered system, which are neutral-delay-dependent, discrete-delay-range-dependent, and distributed-delay-dependent. The conditions are presented in terms of linear matrix inequalities (LMIs and can be efficiently solved using convex programming techniques. Two numerical examples are given to illustrate the efficiency of the proposed method.

CGI delay compensation. [Computer Generated Image

Science.gov (United States)

Mcfarland, R. E.

1986-01-01

Computer-generated graphics in real-time helicopter simulation produces objectionable scene-presentation time delays. In the flight simulation laboratory at Ames Research Center, it has been determined that these delays have an adverse influence on pilot performance during agressive tasks such as nap of the earth (NOE) maneuvers. Using contemporary equipment, computer generated image (CGI) time delays are an unavoidable consequence of the operations required for scene generation. However, providing that magnitude distortions at higher frequencies are tolerable, delay compensation is possible over a restricted frequency range. This range, assumed to have an upper limit of perhaps 10 or 15 rad/sec, conforms approximately to the bandwidth associated with helicopter handling qualities research. A compensation algorithm is introduced here and evaluated in terms of tradeoffs in frequency responses. The algorithm has a discrete basis and accommodates both a large, constant transport delay interval and a periodic delay interval, as associated with asynchronous operations.

Moments of the Wigner delay times

International Nuclear Information System (INIS)

Berkolaiko, Gregory; Kuipers, Jack

2010-01-01

The Wigner time delay is a measure of the time spent by a particle inside the scattering region of an open system. For chaotic systems, the statistics of the individual delay times (whose average is the Wigner time delay) are thought to be well described by random matrix theory. Here we present a semiclassical derivation showing the validity of random matrix results. In order to simplify the semiclassical treatment, we express the moments of the delay times in terms of correlation functions of scattering matrices at different energies. In the semiclassical approximation, the elements of the scattering matrix are given in terms of the classical scattering trajectories, requiring one to study correlations between sets of such trajectories. We describe the structure of correlated sets of trajectories and formulate the rules for their evaluation to the leading order in inverse channel number. This allows us to derive a polynomial equation satisfied by the generating function of the moments. Along with showing the agreement of our semiclassical results with the moments predicted by random matrix theory, we infer that the scattering matrix is unitary to all orders in the semiclassical approximation.

CPD: The patient with daily headaches. | Maizels | South African ...

African Journals Online (AJOL)

The term "chronic daily headache" (CDH) describes a variety of headache types, of which chronic migraine is the most common. Daily headaches often are disabling and may be challenging to diagnose and treat. Medication overuse, or drug rebound headache, is the most treatable cause of refractory daily headache.

Synchronization of Markovian jumping stochastic complex networks with distributed time delays and probabilistic interval discrete time-varying delays

International Nuclear Information System (INIS)

Li Hongjie; Yue Dong

2010-01-01

The paper investigates the synchronization stability problem for a class of complex dynamical networks with Markovian jumping parameters and mixed time delays. The complex networks consist of m modes and the networks switch from one mode to another according to a Markovian chain with known transition probability. The mixed time delays are composed of discrete and distributed delays, the discrete time delay is assumed to be random and its probability distribution is known a priori. In terms of the probability distribution of the delays, the new type of system model with probability-distribution-dependent parameter matrices is proposed. Based on the stochastic analysis techniques and the properties of the Kronecker product, delay-dependent synchronization stability criteria in the mean square are derived in the form of linear matrix inequalities which can be readily solved by using the LMI toolbox in MATLAB, the solvability of derived conditions depends on not only the size of the delay, but also the probability of the delay-taking values in some intervals. Finally, a numerical example is given to illustrate the feasibility and effectiveness of the proposed method.

Spiking Activity of a LIF Neuron in Distributed Delay Framework

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Saket Kumar Choudhary

2016-06-01

Full Text Available Evolution of membrane potential and spiking activity for a single leaky integrate-and-fire (LIF neuron in distributed delay framework (DDF is investigated. DDF provides a mechanism to incorporate memory element in terms of delay (kernel function into a single neuron models. This investigation includes LIF neuron model with two different kinds of delay kernel functions, namely, gamma distributed delay kernel function and hypo-exponential distributed delay kernel function. Evolution of membrane potential for considered models is studied in terms of stationary state probability distribution (SPD. Stationary state probability distribution of membrane potential (SPDV for considered neuron models are found asymptotically similar which is Gaussian distributed. In order to investigate the effect of membrane potential delay, rate code scheme for neuronal information processing is applied. Firing rate and Fano-factor for considered neuron models are calculated and standard LIF model is used for comparative study. It is noticed that distributed delay increases the spiking activity of a neuron. Increase in spiking activity of neuron in DDF is larger for hypo-exponential distributed delay function than gamma distributed delay function. Moreover, in case of hypo-exponential delay function, a LIF neuron generates spikes with Fano-factor less than 1.

Accelerated long-term forgetting in aging and intra-sleep awakenings

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Alison eMary

2013-10-01

Full Text Available The architecture of sleep and the functional neuroanatomical networks subtending memory consolidation processes are both modified with aging, possibly leading to accelerated forgetting in long-term memory. We investigated associative learning and declarative memory consolidation processes in 16 young (18–30 years and 16 older (65–75 years healthy adults. Performance was tested using a cued recall procedure at the end of learning (immediate recall, and 30 minutes and 7 days later. A delayed recognition test was also administered on day 7. Daily sleep diaries were completed during the entire experiment. Results revealed a similar percentage of correct responses at immediate and 30-minute recall in young and older participants. However, recall was significantly decreased 7 days later, with an increased forgetting in older participants. Additionally, intra-sleep awakenings were more frequent in older participants than young adults during the 7 nights, and were negatively correlated with delayed recall performance on day 7 in the older group. Altogether, our results suggest a decline in verbal declarative memory consolidation processes with aging, eventually leading to accelerated long-term forgetting indicating that increased sleep fragmentation due to more frequent intra-sleep awakenings in older participants contribute to the reported age-related decline in long-term memory retrieval. Our results highlight the sensitivity of long-term forgetting measures to evidence consolidation deficits in healthy aging.

Delay-Dependent Stability Criterion for Bidirectional Associative Memory Neural Networks with Interval Time-Varying Delays

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Park, Ju H.; Kwon, O. M.

In the letter, the global asymptotic stability of bidirectional associative memory (BAM) neural networks with delays is investigated. The delay is assumed to be time-varying and belongs to a given interval. A novel stability criterion for the stability is presented based on the Lyapunov method. The criterion is represented in terms of linear matrix inequality (LMI), which can be solved easily by various optimization algorithms. Two numerical examples are illustrated to show the effectiveness of our new result.

Going outdoors daily predicts long-term functional and health benefits among ambulatory older people.

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Jacobs, Jeremy M; Cohen, Aaron; Hammerman-Rozenberg, Robert; Azoulay, Daniel; Maaravi, Yoram; Stessman, Jochanan

2008-04-01

This article examines the association between frequency of going out of the house and health and functional status among older people. A randomly chosen cohort of ambulatory participants born in 1920 or 1921 from the Jerusalem Longitudinal Study underwent assessments for health, functional, and psychosocial variables at ages 70 and 77. Twelve-year mortality data were collected. Women went out daily less than did men. Participants going out daily at age 70 reported significantly fewer new complaints at age 77 of musculoskeletal pain, sleep problems, urinary incontinence, and decline in activities of daily living (ADLs). Logistic regression analysis indicated that not going out daily at age 70 was predictive of subsequent dependence in ADL, poor self-rated health, and urinary incontinence at age 77. Going out daily is beneficial among independent older people, correlating with reduced functional decline and improved health measures.

Delayed consequences of biological action of electromagnetic fields

International Nuclear Information System (INIS)

Grigor'ev, Yu.G.

2000-01-01

Based on available data the real possibility of development of delayed effects in people of long-term electromagnetic fields (EMF) exposure is considered. It is shown that is a relation between long-term EMF-exposure and development of the breast cancer, brain tumors, leukemia and neurodegenerative diseases (Alzheimer's and Parkinson's diseases, amyotrophic lateral sclerosis). Analysis of up-to-date publications permit to conclude that this problem is urgent and further researches of the conditions promoting the development of delayed effects are required [ru

On the Behavioral Side of Procrastination: Exploring Behavioral Delay in Real-Life Settings

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Frode Svartdal

2018-05-01

Full Text Available This paper examines how procrastinators behave differently from non-procrastinators in implementing intended behavior. By focusing on time-related attributes of behavior, we demonstrate in five studies (aggregated N = 965 that onset delay seems to be a preferred option for procrastinators in common daily situations. Thus, when an action possibility is available for intended behavior, procrastinators tend to delay behavior onset, both in actual behavior and in onset preferences, often instigating chains of events with negative consequences. We discuss possible mechanisms responsible for such delays and explore how such mechanisms generate and sustain dilatory behavior. We conclude that a better understanding of why behavioral delays occur in early phases of action implementation is of importance in understanding and preventing procrastination.

On the Behavioral Side of Procrastination: Exploring Behavioral Delay in Real-Life Settings.

Science.gov (United States)

Svartdal, Frode; Granmo, Sjur; Færevaag, Fredrik S

2018-01-01

This paper examines how procrastinators behave differently from non-procrastinators in implementing intended behavior. By focusing on time-related attributes of behavior, we demonstrate in five studies (aggregated N = 965) that onset delay seems to be a preferred option for procrastinators in common daily situations. Thus, when an action possibility is available for intended behavior, procrastinators tend to delay behavior onset, both in actual behavior and in onset preferences, often instigating chains of events with negative consequences. We discuss possible mechanisms responsible for such delays and explore how such mechanisms generate and sustain dilatory behavior. We conclude that a better understanding of why behavioral delays occur in early phases of action implementation is of importance in understanding and preventing procrastination.

A medium-term intervention study on the impact of high- and low-fat snacks varying in sweetness and fat content: large shifts in daily fat intake but good compensation for daily energy intake.

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Lawton, C L; Delargy, H J; Smith, F C; Hamilton, V; Blundell, J E

1998-08-01

Thirty-six normal-weight, habitual snackers (eighteen males, eighteen females) completed a medium-term intervention study designed to examine the tendency of four different types of snacks, varying in nutrient (low- (LF) or high-fat (HF) and sensory properties (sweet (SW) or non-sweet (NSW)), to influence the control of appetite and to adjust daily energy intake. Subjects were exposed to each snack category for a 3-week period and were asked to consume a minimum number of snacks each day so that at least 25% of their daily energy intake would be derived from the test snacks. Energy and macronutrient intakes from the test snacks were calculated every day and also from other eating episodes (using 3 d food diary records) during the third week of snack exposure. Subjects consumed more energy/d from the SW snacks than from the NSW snacks, with most energy being consumed from the HF/SW snacks (3213 kJ) and least energy from the LF/NSW snacks (1628 kJ). This differential snack intake remained stable across the whole snack exposure period. Total daily energy intake did not differ significantly during exposure to any of the four snack types. Furthermore, the encouragement to eat freely from the test snacks did not lead to daily overconsumption of energy when compared with pre-study intakes. Hence, the level of snack consumption was largely compensated for by the energy consumed from the rest of the eating pattern. Although daily energy intake during exposure to the HF snacks was an average of 364 kJ higher (NS) than that during exposure to the LF snacks, the clearest and most significant effect of snack consumption was on daily macronutrient intake. Appreciable consumption of the HF snacks raised the percentage of total daily energy intake consumed as fat from 37 to 41% (P snacks reduced daily fat intake to 33.5% (LF/SW, P snacks, when compared with HF snacks, is an effective strategy to reduce fat intake so that it approaches the recommendations of dietary guidelines

Modelling and short-term forecasting of daily peak power demand in Victoria using two-dimensional wavelet based SDP models

International Nuclear Information System (INIS)

Truong, Nguyen-Vu; Wang, Liuping; Wong, Peter K.C.

2008-01-01

Power demand forecasting is of vital importance to the management and planning of power system operations which include generation, transmission, distribution, as well as system's security analysis and economic pricing processes. This paper concerns the modeling and short-term forecast of daily peak power demand in the state of Victoria, Australia. In this study, a two-dimensional wavelet based state dependent parameter (SDP) modelling approach is used to produce a compact mathematical model for this complex nonlinear dynamic system. In this approach, a nonlinear system is expressed by a set of linear regressive input and output terms (state variables) multiplied by the respective state dependent parameters that carry the nonlinearities in the form of 2-D wavelet series expansions. This model is identified based on historical data, descriptively representing the relationship and interaction between various components which affect the peak power demand of a certain day. The identified model has been used to forecast daily peak power demand in the state of Victoria, Australia in the time period from the 9th of August 2007 to the 24th of August 2007. With a MAPE (mean absolute prediction error) of 1.9%, it has clearly implied the effectiveness of the identified model. (author)

Dynamics of a delayed intraguild predation model with harvesting

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Collera, Juancho A.; Balilo, Aldrin T.

2018-03-01

In [1], a delayed three-species intraguild predation (IGP) model was considered. This particular tri-trophic community module includes a predator and its prey which share a common basal resource for their sustenance [3]. Here, it is assumed that in the absence of predation, the growth of the basal resource follows the delayed logistic equation. Without delay time, the IGP model in [1] reduces to the system considered in [7] where it was shown that IGP may induce chaos even if the functional responses are linear. Meanwhile, in [2] the delayed IGP model in [1] was generalized to include harvesting. Under the assumption that the basal resource has some economic value, a constant harvesting term on the basal resource was incorporated. However, both models in [1] and [2] use the delay time as the main parameter. In this research, we studied the delayed IGP model in [1] with the addition of linear harvesting term on each of the three species. The dynamical behavior of this system is examined using the harvesting rates as main parameter. In particular, we give conditions on the existence, stability, and bifurcations of equilibrium solutions of this system. This allows us to better understand the effects of harvesting in terms of the survival or extinction of one or more species in our system. Numerical simulations are carried out to illustrate our results. In fact, we show that the chaotic behavior in [7] unfolds when the harvesting rate parameter is varied.

Termination of short term melatonin treatment in children with delayed Dim Light Melatonin Onset: effects on sleep, health, behavior problems, and parenting stress

NARCIS (Netherlands)

van Maanen, Annette; Meijer, Anne Marie; Smits, Marcel G.; Oort, Frans J.

2011-01-01

To investigate the effects of termination of short term melatonin treatment on sleep, health, behavior, and parenting stress in children with delayed Dim Light Melatonin Onset. Forty-one children (24 boys, 17 girls; mean age=9.43 years) entered melatonin treatment for 3 weeks and then discontinued

Does stress affect the joints? Daily stressors, stress vulnerability, immune and HPA axis activity, and short-term disease and symptom fluctuations in rheumatoid arthritis.

Science.gov (United States)

Evers, Andrea W M; Verhoeven, Elisabeth W M; van Middendorp, Henriët; Sweep, Fred C G J; Kraaimaat, Floris W; Donders, A Rogier T; Eijsbouts, Agnes E; van Laarhoven, Antoinette I M; de Brouwer, Sabine J M; Wirken, Lieke; Radstake, Timothy R D J; van Riel, Piet L C M

2014-09-01

Both stressors and stress vulnerability factors together with immune and hypothalamus-pituitary-adrenal (HPA) axis activity components have been considered to contribute to disease fluctuations of chronic inflammatory diseases, such as rheumatoid arthritis (RA). The aim of the present study was to investigate whether daily stressors and worrying as stress vulnerability factor as well as immune and HPA axis activity markers predict short-term disease activity and symptom fluctuations in patients with RA. In a prospective design, daily stressors, worrying, HPA axis (cortisol) and immune system (interleukin (IL)-1β, IL-6, IL-8, interferon (IFN)-γ, tumour necrosis factor α) markers, clinical and self-reported disease activity (disease activity score in 28 joints, RA disease activity index), and physical symptoms of pain and fatigue were monitored monthly during 6 months in 80 RA patients. Multilevel modelling indicated that daily stressors predicted increased fatigue in the next month and that worrying predicted increased self-reported disease activity, swollen joint count and pain in the next month. In addition, specific cytokines of IL-1β and IFN-γ predicted increased fatigue 1 month later. Overall, relationships remained relatively unchanged after controlling for medication use, disease duration and demographic variables. No evidence was found for immune and HPA axis activity markers as mediators of the stress-disease relationship. Daily stressors and the stress-vulnerability factor worrying predict indicators of the short-term course of RA disease activity and fatigue and pain, while specific cytokines predict short-term fluctuations of fatigue. These stress-related variables and immune markers seem to affect different aspects of disease activity or symptom fluctuations independently in RA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Best matching Barenblatt profiles are delayed

International Nuclear Information System (INIS)

Dolbeault, Jean; Toscani, Giuseppe

2015-01-01

The growth of the second moments of the solutions of fast diffusion equations is asymptotically governed by the behavior of self-similar solutions. However, at next order, there is a correction term which amounts to a delay depending on the nonlinearity and on a distance of the initial data to the set of self-similar Barenblatt solutions. This distance can be measured in terms of a relative entropy to the best matching Barenblatt profile. This best matching Barenblatt function determines a scale. In new variables based on this scale, which are given by a self-similar change of variables if and only if the initial datum is one of the Barenblatt profiles, the typical scale is monotone and has a limit. Coming back to original variables, the best matching Barenblatt profile is delayed compared to the self-similar solution with same initial second moment as the initial datum. Such a delay is a new phenomenon, which has to be taken into account for instance when fitting experimental data. (paper)

Daily impaired detachment and short-term effects of impaired sleep quality on next-day commuting near-accidents - an ambulatory diary study.

Science.gov (United States)

Pereira, Diana; Bucher, Sarah; Elfering, Achim

2016-08-01

This study investigated the short-term effects of daily recovery, that is, impaired psychological detachment from work and various actigraphical indicators of sleep quality, on near-accidents when commuting to work the next morning. Furthermore, the mediating effect of actigraphically assessed sleep quality on the relationship between impaired psychological detachment from work and near-accidents when commuting to work was analysed. Fifty-six full-time employees of a Swiss assurance company participated in the one-week study. Multilevel analyses revealed that impaired detachment was highly related to a decrease in sleep duration. Furthermore, impaired daily recovery processes, such as impaired psychological detachment from work and disturbed sleep quality, were related to commuting near-accidents. Impaired sleep quality mediated the effect of impaired psychological detachment from work on these near-accidents. Our results show that occupational safety interventions should address both impaired psychological detachment from work and sleep quality in order to prevent near accidents when commuting to work. Practitioner Summary: Commuting accidents occur frequently and have detrimental effects on employees, organisations and society. This study shows that daily lack of recovery, that is, impaired psychological detachment and impaired sleep quality, is related to near-accidents when commuting to work the next morning. Primary prevention of commuting accidents should therefore address daily lack of recovery.

Delay-related cerebral activity and motor preparation

NARCIS (Netherlands)

Mars, R.B.; Coles, M.G.H.; Hulstijn, W.

2008-01-01

Flexible goal-oriented behavior requires the ability to carry information across temporal delays. This ability is associated with sustained neural firing. In cognitive terms, this ability has often been associated with the maintenance of sensory material online, as during short-term memory tasks, or

Delayed somatic effects following extended radiotherapy. Studies of 135 patients with Hodgkin's disease in long-term remission (Freiburg collective, treatment years 1948 to 1974). Untersuchungen ueber somatische Spaetschaeden nach ausgedehnter Strahlentherapie

Energy Technology Data Exchange (ETDEWEB)

Slanina, J

1977-01-01

A group of 135 patients who suffered from Hodgkin's disease with long-term remission following radiotherapy was investigated. By restricting the investigations to the patient group with long-term remission and correlative examinations, it was tried to differentiate between exclusive or principal delayed radiation effects and delayed effects due to other factors. The study reports about the most significant results obtained in the fields of catamnesis, laboratory diagnostics, hematology, pulmology, cardiology, thyroid function tests, neurology, andrology and dermatology. Due to the numerous detectable delayed effects the group of patients with long-term remission receives a special status. Although those effects are in no proportion to the deletary risks of an untreated Hodgkin's disease and though they are consequently tolerable in the present state of the therapeutic development, they must initiate the completion of the therapeutic concept including performance of radiotherapy and aftercare, because only then the risk for the patient provoked by these effects, which ranges beyond the malignity of this disease can be reduced or prevented.

Geometric patterns of time-delay plots from different cardiac rhythms and arrhythmias using short-term EKG signals.

Science.gov (United States)

Borracci, Raúl A; Montoya Pulvet, José D; Ingino, Carlos A; Fitz Maurice, Mario; Hirschon Prado, Alfredo; Dominé, Enrique

2017-12-27

To date, no systematic work has been intended to describe spatio-temporal patterns of cardiac rhythms using only short series of RR intervals, to facilitate visual or computerized-aided identification of EKG motifs for use in clinical practice. The aim of this study was to detect and classify eye-catching geometric patterns of Poincaré time-delay plots from different types of cardiac rhythms and arrhythmias using short-term EKG signals. Approximately 150-300 representative, consecutive beats were retrieved from 24-h Holter registers of 100 patients with different heart rhythms. Two-dimensional Poincaré charts were created, and the resulting geometric patterns were transformed into representative familiar eye-catching drawings to interpret different arrhythmias. Poincaré plot representation of RR interval data revealed a wide variety of visual patterns: (i) comet-shaped for sinus rhythm; (ii) torpedo-shaped for sinus bradycardia; (iii) cigarette-shaped for sinus tachycardia; (iv) butterfly-shaped for sinus tachycardia and isolated atrial premature complexes; (v) arrow-shaped for isolated premature complexes and inappropriate sinus tachycardia; (vi) inverted fan-shaped for sinus rhythm with frequent atrial premature complexes; (vii) tornado-shaped for atrial flutter and atrial tachycardia; and (viii) fan-shaped for atrial fibrillation. Modified Poincaré plots with smoothed lines connecting successive points could accurately classify different types of arrhythmias based on short RR interval sequence variability. Characteristic emergent patterns can be visually identified and eventually could be distinguished by an automatic classification system able to discern between arrhythmias. This work provides an alternative method to interpret time-delay plots obtained from short-term EKG signal recordings. © 2017 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

When good pigeons make bad decisions: Choice with probabilistic delays and outcomes.

Science.gov (United States)

Pisklak, Jeffrey M; McDevitt, Margaret A; Dunn, Roger M; Spetch, Marcia L

2015-11-01

Pigeons chose between an (optimal) alternative that sometimes provided food after a 10-s delay and other times after a 40-s delay and another (suboptimal) alternative that sometimes provided food after 10 s but other times no food after 40 s. When outcomes were not signaled during the delays, pigeons strongly preferred the optimal alternative. When outcomes were signaled, choices of the suboptimal alternative increased and most pigeons preferred the alternative that provided no food after the long delay despite the cost in terms of obtained food. The pattern of results was similar whether the short delays occurred on 25% or 50% of the trials. Shortening the 40-s delay to food sharply reduced suboptimal choices, but shortening the delay to no food had little effect. The results suggest that a signaled delay to no food does not punish responding in probabilistic choice procedures. The findings are discussed in terms of conditioned reinforcement by signals for good news. © Society for the Experimental Analysis of Behavior.

Memory persistency and nonlinearity in daily mean dew point across India

Science.gov (United States)

Ray, Rajdeep; Khondekar, Mofazzal Hossain; Ghosh, Koushik; Bhattacharjee, Anup Kumar

2016-04-01

Enterprising endeavour has been taken in this work to realize and estimate the persistence in memory of the daily mean dew point time series obtained from seven different weather stations viz. Kolkata, Chennai (Madras), New Delhi, Mumbai (Bombay), Bhopal, Agartala and Ahmedabad representing different geographical zones in India. Hurst exponent values reveal an anti-persistent behaviour of these dew point series. To affirm the Hurst exponent values, five different scaling methods have been used and the corresponding results are compared to synthesize a finer and reliable conclusion out of it. The present analysis also bespeaks that the variation in daily mean dew point is governed by a non-stationary process with stationary increments. The delay vector variance (DVV) method has been exploited to investigate nonlinearity, and the present calculation confirms the presence of deterministic nonlinear profile in the daily mean dew point time series of the seven stations.

Light pollution modifies the expression of daily rhythms and behavior patterns in a nocturnal primate.

Directory of Open Access Journals (Sweden)

Thomas Le Tallec

Full Text Available Among anthropogenic pressures, light pollution altering light/dark cycles and changing the nocturnal component of the environment constitutes a threat for biodiversity. Light pollution is widely spread across the world and continuously growing. However, despite the efforts realized to describe and understand the effects of artificial lighting on fauna, few studies have documented its consequences on biological rhythms, behavioral and physiological functions in nocturnal mammals. To determine the impacts of light pollution on nocturnal mammals an experimental study was conducted on a nocturnal primate, the grey mouse lemur Microcebus murinus. Male mouse lemurs (N = 8 were exposed 14 nights to moonlight treatment and then exposed 14 nights to light pollution treatment. For both treatments, chronobiological parameters related to locomotor activity and core temperature were recorded using telemetric transmitters. In addition, at the end of each treatment, the 14(th night, nocturnal and feeding behaviors were explored using an infrared camera. Finally, throughout the study, body mass and daily caloric food intake were recorded. For the first time in a nocturnal primate, light pollution was demonstrated to modify daily rhythms of locomotor activity and core temperature especially through phase delays and increases in core temperature. Moreover, nocturnal activity and feeding behaviors patterns were modified negatively. This study suggests that light pollution induces daily desynchronization of biological rhythms and could lead to seasonal desynchronization with potential deleterious consequences for animals in terms of adaptation and anticipation of environmental changes.

Light pollution modifies the expression of daily rhythms and behavior patterns in a nocturnal primate.

Science.gov (United States)

Le Tallec, Thomas; Perret, Martine; Théry, Marc

2013-01-01

Among anthropogenic pressures, light pollution altering light/dark cycles and changing the nocturnal component of the environment constitutes a threat for biodiversity. Light pollution is widely spread across the world and continuously growing. However, despite the efforts realized to describe and understand the effects of artificial lighting on fauna, few studies have documented its consequences on biological rhythms, behavioral and physiological functions in nocturnal mammals. To determine the impacts of light pollution on nocturnal mammals an experimental study was conducted on a nocturnal primate, the grey mouse lemur Microcebus murinus. Male mouse lemurs (N = 8) were exposed 14 nights to moonlight treatment and then exposed 14 nights to light pollution treatment. For both treatments, chronobiological parameters related to locomotor activity and core temperature were recorded using telemetric transmitters. In addition, at the end of each treatment, the 14(th) night, nocturnal and feeding behaviors were explored using an infrared camera. Finally, throughout the study, body mass and daily caloric food intake were recorded. For the first time in a nocturnal primate, light pollution was demonstrated to modify daily rhythms of locomotor activity and core temperature especially through phase delays and increases in core temperature. Moreover, nocturnal activity and feeding behaviors patterns were modified negatively. This study suggests that light pollution induces daily desynchronization of biological rhythms and could lead to seasonal desynchronization with potential deleterious consequences for animals in terms of adaptation and anticipation of environmental changes.

Re: What is the best treatment to reduce the need for caesarean section in nulliparous women at term with delayed first stage of labour?

DEFF Research Database (Denmark)

Boie, Sidsel; Glavind, Julie; Uldbjerg, Niels

2017-01-01

The authors pose the question - What is the best treatment to reduce the need for caesarean section in nulliparous women at term with delayed first stage of labour? and state in their paper that "There is no consensus on the optimal dose regimen of oxytocin for delay in the first stage of labour...... in nulliparous women at term (37-42 weeks’ gestation) to reduce unplanned caesarean section and increase vaginal birth with minimal adverse events". However, they describe only low and high dose oxytocin regimens and fail to acknowledge that no oxytocin at all is associated with a spontaneous delivery just...... as often as when oxytocin is given (1,2) or that discontinuation of oxytocin once the active phase of labour is reached can result in higher spontaneous delivery rates than continuing oxytocin (3,4). The paper in its list of trials (box 2) only describes those addressing high and low dose oxytocin, which...

Usefulness of Daily Fractionated Administration of Wortmannin Combined With γ-Ray Irradiation in Terms of Local Tumor Response and Lung Metastasis

Science.gov (United States)

Masunaga, Shin-ichiro; Sakurai, Yoshinori; Tanaka, Hiroki; Suzuki, Minoru; Kondo, Natsuko; Narabayashi, Masaru; Tano, Keizo; Maruhashi, Akira; Ono, Koji

2013-01-01

Background To evaluate the usefulness of fractionated administration of wortmannin combined with γ-ray irradiation in terms of local tumor response and lung metastatic potential, referring to the response of intratumor quiescent (Q) cells. Methods B16-BL6 melanoma tumor-bearing C57BL/6 mice were continuously given 5-bromo-2’-deoxyuridine (BrdU) to label all proliferating (P) cells. The tumor-bearing mice then received γ-ray irradiation after wortmannin treatment through a single or 4 consecutive daily intraperitoneal administrations up to a total dose of 4 mg/kg in combination with an acute hypoxia-releasing agent (nicotinamide) or mild temperature hyperthermia (MTH). Immediately after the irradiation, cells from some tumors were isolated and incubated with a cytokinesis blocker. The responses of the Q and total (= P + Q) cell populations were assessed based on the frequency of micronuclei using immunofluorescence staining for BrdU. In other tumor-bearing mice, 17 days after irradiation, macroscopic lung metastases were enumerated. Results Wortmannin raised the sensitivity of Q cells more remarkably than the total cell population in both single and daily administrations. Daily administration of wortmannin elevated the sensitivity of both the total and Q cell populations, but especially the total cell population, compared with single administration. Daily administration, especially combined with MTH, decreased the number of lung metastases. Conclusion Daily fractionated administration of wortmannin in combination with γ-ray irradiation was thought to be more promising than single administration because of its potential to enhance local tumor response and repress lung metastatic potential. PMID:29147327

On-demand SSRI treatment of premature ejaculation: pharmacodynamic limitations for relevant ejaculation delay and consequent solutions.

Science.gov (United States)

Waldinger, Marcel D; Schweitzer, Dave H; Olivier, Berend

2005-01-01

Recently, the idea has emerged that on-demand use of serotonin reuptake inhibitors (SSRIs), particularly short half-life, should be equally effective in delaying ejaculation as daily SSRI treatment of premature ejaculation. To provide evidence that SSRI-induced ejaculation delay is mainly dependent on pharmacodynamic properties of the drug and hardly on pharmacokinetic factors, and that combined SSRI administration with specific 5-hydroxytryptamine (5-HT) receptor antagonism leads acutely to stronger ejaculation delay than acute SSRI monoadministration. We performed a detailed analysis of serotonin neurotransmission and reviewed animal studies with 5-HT(1A) receptor antagonists. In addition, we critically reviewed existing on-demand SSRI treatments publications and the current debate on a definition of premature ejaculation. Intravaginal ejaculation latency time (IELT). Acute SSRI administration leads to only a mild or no increase of 5-HT neurotransmission and concomitant stimulation of postsynaptic 5-HT receptors. Existing on-demand SSRI treatment studies suffer from methodological insufficiencies, and the reported high-fold increases of ejaculation time contradict with neuropharmacological insights from serotonin metabolism. Animal studies show that SSRI coadministration with 5-HT(1A) receptor antagonists significantly increases the ejaculation time acutely compared to acute SSRI monoadministration. On-demand SSRI treatment has less ejaculation-delaying effects than daily SSRI treatment. SSRIs with a short half-life are likely leading to much less ejaculation delay than current registered SSRIs. Combined use of SSRIs with 5-HT(1A) receptor antagonists increases the likelihood of clinically relevant ejaculation delay after on-demand treatment. On-demand SSRIs with short half-life that insufficiently delay ejaculation in men with IELTs less than 1 minute should be called ejaculation-delaying drugs rather than drugs against premature ejaculation.

Delay-dependent exponential stability for neural networks with discrete and distributed time-varying delays

International Nuclear Information System (INIS)

Zhu Xunlin; Wang Youyi

2009-01-01

This Letter studies the exponential stability for a class of neural networks (NNs) with both discrete and distributed time-varying delays. Under weaker assumptions on the activation functions, by defining a more general type of Lyapunov functionals and developing a new convex combination technique, new less conservative and less complex stability criteria are established to guarantee the global exponential stability of the discussed NNs. The obtained conditions are dependent on both discrete and distributed delays, are expressed in terms of linear matrix inequalities (LMIs), and contain fewer decision variables. Numerical examples are given to illustrate the effectiveness and the less conservatism of the proposed conditions.

Existence and asymptotic stability of a viscoelastic wave equation with a delay

KAUST Repository

Kirane, Mokhtar

2011-07-07

In this paper, we consider the viscoelastic wave equation with a delay term in internal feedbacks; namely, we investigate the following problem, together with initial conditions and boundary conditions of Dirichlet type. Here (x, t) ∈ Ω × (0, ∞), g is a positive real valued decreasing function and μ1, μ2 are positive constants. Under an hypothesis between the weight of the delay term in the feedback and the weight of the term without delay, using the Faedo-Galerkin approximations together with some energy estimates, we prove the global existence of the solutions. Under the same assumptions, general decay results of the energy are established via suitable Lyapunov functionals. © 2011 Springer Basel AG.

Existence and asymptotic stability of a viscoelastic wave equation with a delay

KAUST Repository

Kirane, Mokhtar; Said-Houari, Belkacem

2011-01-01

In this paper, we consider the viscoelastic wave equation with a delay term in internal feedbacks; namely, we investigate the following problem, together with initial conditions and boundary conditions of Dirichlet type. Here (x, t) ∈ Ω × (0, ∞), g is a positive real valued decreasing function and μ1, μ2 are positive constants. Under an hypothesis between the weight of the delay term in the feedback and the weight of the term without delay, using the Faedo-Galerkin approximations together with some energy estimates, we prove the global existence of the solutions. Under the same assumptions, general decay results of the energy are established via suitable Lyapunov functionals. © 2011 Springer Basel AG.

Finite-Time Attractivity for Diagonally Dominant Systems with Off-Diagonal Delays

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T. S. Doan

2012-01-01

Full Text Available We introduce a notion of attractivity for delay equations which are defined on bounded time intervals. Our main result shows that linear delay equations are finite-time attractive, provided that the delay is only in the coupling terms between different components, and the system is diagonally dominant. We apply this result to a nonlinear Lotka-Volterra system and show that the delay is harmless and does not destroy finite-time attractivity.

Delayed appearance of tracer lead in facial hair

International Nuclear Information System (INIS)

Rabinowitz, M.; Wetherill, G.; Kopple, J.

1976-01-01

Three adult men were fed 204 Pb--a rare, stable isotope of lead--daily for about 100 days. Simultaneous blood and facial hair measurements of this tracer and of total lead concentrations were made by mass spectrometric isotope dilution analysis. Although the blood showed an immediate response to the intake of the tracer, the facial hair showed a more gradual response and a delay of approximately 35 days. Since the pattern of appearance of lead in hair does not appear to represent a simple time delay of blood lead concentration, the existence of a physiological pool of lead fed by the blood and giving rise to the content in hair is suggested. Hair lead values should therefore, be interpreted as the integral of the blood lead values over the mean life of this intermediate pool--about 100 days

The administration of long-term high-fat diet in ovariectomized wistar rat (Study on Daily Food Intake, Lee Index, Abdominal Fat Mass and Leptin Serum Levels

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Dita Fitriani

2016-12-01

Conclusion: Serum leptin levels positively correlated with Lee index and abdominal fat mass, but negatively correlated with daily food intake. Administration of long-term high-fat diet in this study cannot induce leptin resistance.

Passivity analysis and synthesis for uncertain time-delay systems

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Magdi S. Mahmoud

2001-01-01

Full Text Available In this paper, we investigate the robust passivity analysis and synthesis problems for a class of uncertain time-delay systems. This class of systems arises in the modelling effort of studying water quality constituents in fresh stream. For the analysis problem, we derive a sufficient condition for which the uncertain time-delay system is robustly stable and strictly passive for all admissible uncertainties. The condition is given in terms of a linear matrix inequality. Both the delay-independent and delay-dependent cases are considered. For the synthesis problem, we propose an observer-based design method which guarantees that the closed-loop uncertain time-delay system is stable and strictly passive for all admissible uncertainties. Several examples are worked out to illustrate the developed theory.

Examining weight concern and delay discounting in adolescent females.

Science.gov (United States)

Thamotharan, Sneha; Lange, Krista; Ramos, Ashley; Fields, Sherecce

2016-04-01

Pediatric obesity is a growing public health concern that contributes to high rates of negative long-term physical and mental health outcomes. Research focused on identifying risk for pediatric obesity has linked delay discounting, or an inclination for immediate rewards, as well as weight concern to individuals with greater Body Mass Index (BMI). The current study seeks to fill a void in the literature by examining how these two variables interact to promote higher BMI in female adolescents. Adolescent (n=60) females between the ages of 13-19years (mage=17.45, SD=1.74) of age completed the Eating Disorder Examination Questionnaire (EDE-Q) and the Delay Discounting Questionnaire. A mediation model examined whether delay discounting accounted for the relationship between weight concern and BMI. Results indicate that in the current study weight concern was negatively related to delay discounting and delay discounting was negatively related to BMI. The overall model revealed that a partial mediation occurred [b=1.28, t(60)=4.92, pconcerns contribute to greater BMI. Nevertheless, the results indicate that prevention and interventions should identify females with high levels of both weight concern and impulsivity as an increased risk for experiencing pediatric obesity and long-term negative health outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Infants' Delayed Recognition Memory and Forgetting

Science.gov (United States)

Fagan, Joseph F., III

1973-01-01

Infants 21- to 25-weeks-old devoted more visual fixation to novel than familiar stimuli on immediate and delayed recognition tests. The experiments confirm the existence of long-term recognition memory for pictorial stimuli in the early months of life. (DP)

Long-Term Maintenance of Immediate or Delayed Extinction Is Determined by the Extinction-Test Interval

Science.gov (United States)

Johnson, Justin S.; Escobar, Martha; Kimble, Whitney L.

2010-01-01

Short acquisition-extinction intervals (immediate extinction) can lead to either more or less spontaneous recovery than long acquisition-extinction intervals (delayed extinction). Using rat subjects, we observed less spontaneous recovery following immediate than delayed extinction (Experiment 1). However, this was the case only if a relatively…

Activities of daily living and oral hygiene status of older Korean patients in a long-term care facility.

Science.gov (United States)

Seo, H-Y; Jeon, J-E; Chung, W-G; Kim, N-H

2017-05-01

This study investigated the relationship between oral hygiene conditions, activities of daily living (ADL) and cognitive ability in older Korean patients in long-term care facilities. Ninety older persons (65+) were randomly sampled from a possible 112 residents in a single facility. They participated in a 2-month-long survey. The Korean Modified Barthel Index was used to measure the ADL, and cognitive ability was measured using the Mini-Mental State Examination, Korean version. Oral hygiene status was measured using the Simplified Oral Hygiene Index and the Tongue Coating Index (TCI). Older participants with complete dependence manifested significantly poorer oral hygiene (P oral hygiene (P oral hygiene on tooth surfaces, while participants with partial dependence had poor tongue hygiene. In addition, dentulous older participants had poorer tongue hygiene than edentulous ones. This indicates the need to assess tooth status and provide oral care services via ADL in long-term care facilities. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Modeling delay in genetic networks: from delay birth-death processes to delay stochastic differential equations.

Science.gov (United States)

Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Bennett, Matthew R; Josić, Krešimir; Ott, William

2014-05-28

Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay.

Modeling delay in genetic networks: From delay birth-death processes to delay stochastic differential equations

Energy Technology Data Exchange (ETDEWEB)

Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Ott, William [Department of Mathematics, University of Houston, Houston, Texas 77004 (United States); Bennett, Matthew R. [Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77204, USA and Institute of Biosciences and Bioengineering, Rice University, Houston, Texas 77005 (United States); Josić, Krešimir [Department of Mathematics, University of Houston, Houston, Texas 77004 (United States); Department of Biology and Biochemistry, University of Houston, Houston, Texas 77204 (United States)

2014-05-28

Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay.

Modeling delay in genetic networks: From delay birth-death processes to delay stochastic differential equations

International Nuclear Information System (INIS)

Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Ott, William; Bennett, Matthew R.; Josić, Krešimir

2014-01-01

Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay

Dynamic IQC-Based Control of Uncertain LFT Systems With Time-Varying State Delay.

Science.gov (United States)

Yuan, Chengzhi; Wu, Fen

2016-12-01

This paper presents a new exact-memory delay control scheme for a class of uncertain systems with time-varying state delay under the integral quadratic constraint (IQC) framework. The uncertain system is described as a linear fractional transformation model including a state-delayed linear time-invariant (LTI) system and time-varying structured uncertainties. The proposed exact-memory delay controller consists of a linear state-feedback control law and an additional term that captures the delay behavior of the plant. We first explore the delay stability and the L 2 -gain performance using dynamic IQCs incorporated with quadratic Lyapunov functions. Then, the design of exact-memory controllers that guarantee desired L 2 -gain performance is examined. The resulting delay control synthesis conditions are formulated in terms of linear matrix inequalities, which are convex on all design variables including the scaling matrices associated with the IQC multipliers. The IQC-based exact-memory control scheme provides a novel approach for delay control designs via convex optimization, and advances existing control methods in two important ways: 1) better controlled performance and 2) simplified design procedure with less computational cost. The effectiveness and advantages of the proposed approach have been demonstrated through numerical studies.

A Mobile Early Stimulation Program to Support Children with Developmental Delays in Brazil.

Science.gov (United States)

Dias, Raquel da Luz; Silva, Kátia Cristina Correa Guimarães; Lima, Marcela Raquel de Oliveira; Alves, João Guilherme Bezerra; Abidi, Syed Sibte Raza

2018-01-01

Developmental delay is a deviation development from the normative milestones during the childhood and it may be caused by neurological disorders. Early stimulation is a standardized and simple technique to treat developmental delays in children (aged 0-3 years), allowing them to reach the best development possible and to mitigate neuropsychomotor sequelae. However, the outcomes of the treatment depending on the involvement of the family, to continue the activities at home on a daily basis. To empower and educate parents of children with neurodevelopmental delays to administer standardized early stimulation programs at home, we developed a mobile early stimulation program that provides timely and evidence-based clinical decision support to health professionals and a personalized guidance to parents about how to administer early stimulation to their child at home.

Short-term Recovery after Orthognathic Surgery: A Medical Daily Diary Approach

Science.gov (United States)

Blakey, George

2008-01-01

This study assessed the utility of a quality-of-life diary for the assessment of postoperative recovery following orthognathic surgery. A 20-item daily recovery diary was designed to assess the patients’ perception of recovery in 4 domains (postoperative sequelae; pain/discomfort; oral function; daily activities) during each of the first 90 days after surgery. Fifteen of 185 patients who had agreed to participate did not return any portion of the diary. Of the remaining patients, 87% returned the full 90 days requested. Younger patients were more likely to complete the entire protocol (P = 0.01). At 30 days, a lower percentage, in general, of patients who completed all 90 days reported recovery in oral function and general activity compared with those who did not complete all diary days. This study confirms that patients will cooperate with the completion of structured medical / health-related quality-of-life diaries during the first few months after orthognathic surgery. Information from such diaries would be valuable to patients deciding on treatment options and to the clinicians counseling them. PMID:18768296

Resident challenges with daily life in Chinese long-term care facilities: A qualitative pilot study.

Science.gov (United States)

Song, Yuting; Scales, Kezia; Anderson, Ruth A; Wu, Bei; Corazzini, Kirsten N

As traditional family-based care in China declines, the demand for residential care increases. Knowledge of residents' experiences with long-term care (LTC) facilities is essential to improving quality of care. This pilot study aimed to describe residents' experiences in LTC facilities, particularly as it related to physical function. Semi-structured open-ended interviews were conducted in two facilities with residents stratified by three functional levels (n = 5). Directed content analysis was guided by the Adaptive Leadership Framework. A two-cycle coding approach was used with a first-cycle descriptive coding and second-cycle dramaturgical coding. Interviews provided examples of challenges faced by residents in meeting their daily care needs. Five themes emerged: staff care, care from family members, physical environment, other residents in the facility, and personal strategies. Findings demonstrate the significance of organizational context for care quality and reveal foci for future research. Copyright © 2017 Elsevier Inc. All rights reserved.

A Sociability-Based Routing Scheme for Delay-Tolerant Networks

Directory of Open Access Journals (Sweden)

Fabbri Flavio

2011-01-01

Full Text Available The problem of choosing the best forwarders in Delay-Tolerant Networks (DTNs is crucial for minimizing the delay in packet delivery and for keeping the amount of generated traffic under control. In this paper, we introduce sociable routing, a novel routing strategy that selects a subset of optimal forwarders among all the nodes and relies on them for an efficient delivery. The key idea is that of assigning to each network node a time-varying scalar parameter which captures its social behavior in terms of frequency and types of encounters. This sociability concept is widely discussed and mathematically formalized. Simulation results of a DTN of vehicles in urban environment, driven by real mobility traces, and employing sociable routing, is presented. Encouraging results show that sociable routing, compared to other known protocols, achieves a good compromise in terms of delay performance and amount of generated traffic.

Delayed echolalia in autism: some observations on differences within the term.

Science.gov (United States)

Dyer, C; Hadden, A J

1981-01-01

Attention has recently focused on the need to build up a corpus of case observations relating to the function of delayed echolalia in various handicapping conditions but especially in early childhood autism. This present article offers six functional categories as an aid to clear reporting of observation and, thus clarification of this little-understood facet of deviant language development.

Correlation between hyperbilirubinemia in term infants and developmental delay in 2-4 year-old children

Directory of Open Access Journals (Sweden)

Rocky Wilar

2010-06-01

medical record of infants born between 2006-2007 in Division of Neonatology Prof. R.D. Kandoll General Hospital, Manado. Data from the medical record consisted of weeks of gestation, birth weight, Apgar scores, diagnosis of sepsis, congenital anomalies. Tenn infants with appropriate weight for gestational age were visited at their home to undergo developmental screening by Denver II and Vineland Social Maturity Scale test. Results Fifty one children enrolled in this study (26 children with hyperbilirubinemia and 25 without  hyperbilirubinemia consisted of 27 boys and 24 girls. Most children were 24 - 29 months old (24/51. The results of Vineland Social Maturity Scale test showed 14 children had delayed social maturation (10 Mth history of  hyperbilirubinemia. Denver II screening found 11 children had delayed language skill (10 Mth history of hyperbilirubinemia, 1 child Mth hyperbilirubinemia had delayed fine motoric and language skill. Conclusions T here is a relationship between moderate hyperbilirubinemia in tenn infants and developmental delay in 2 - 4 year old children.

Double Hopf bifurcation in delay differential equations

Directory of Open Access Journals (Sweden)

Redouane Qesmi

2014-07-01

Full Text Available The paper addresses the computation of elements of double Hopf bifurcation for retarded functional differential equations (FDEs with parameters. We present an efficient method for computing, simultaneously, the coefficients of center manifolds and normal forms, in terms of the original FDEs, associated with the double Hopf singularity up to an arbitrary order. Finally, we apply our results to a nonlinear model with periodic delay. This shows the applicability of the methodology in the study of delay models arising in either natural or technological problems.

Resting-state EEG, impulsiveness, and personality in daily and nondaily smokers.

Science.gov (United States)

Rass, Olga; Ahn, Woo-Young; O'Donnell, Brian F

2016-01-01

Resting EEG is sensitive to transient, acute effects of nicotine administration and abstinence, but the chronic effects of smoking on EEG are poorly characterized. This study measures the resting EEG profile of chronic smokers in a non-deprived, non-peak state to test whether differences in smoking behavior and personality traits affect pharmaco-EEG response. Resting EEG, impulsiveness, and personality measures were collected from daily smokers (n=22), nondaily smokers (n=31), and non-smokers (n=30). Daily smokers had reduced resting delta and alpha EEG power and higher impulsiveness (Barratt Impulsiveness Scale) compared to nondaily smokers and non-smokers. Both daily and nondaily smokers discounted delayed rewards more steeply, reported lower conscientiousness (NEO-FFI), and reported greater disinhibition and experience seeking (Sensation Seeking Scale) than non-smokers. Nondaily smokers reported greater sensory hedonia than nonsmokers. Altered resting EEG power in daily smokers demonstrates differences in neural signaling that correlated with greater smoking behavior and dependence. Although nondaily smokers share some characteristics with daily smokers that may predict smoking initiation and maintenance, they differ on measures of impulsiveness and resting EEG power. Resting EEG in non-deprived chronic smokers provides a standard for comparison to peak and trough nicotine states and may serve as a biomarker for nicotine dependence, relapse risk, and recovery. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Resting-state EEG, Impulsiveness, and Personality in Daily and Nondaily Smokers†

Science.gov (United States)

Rass, Olga; Ahn, Woo-Young; O’Donnell, Brian F.

2015-01-01

Objectives Resting EEG is sensitive to transient, acute effects of nicotine administration and abstinence, but the chronic effects smoking on EEG are poorly characterized. This study measures the resting EEG profile of chronic smokers in a non-deprived, non-peak state to test whether differences in smoking behavior and personality traits affect pharmaco-EEG response. Methods Resting EEG, impulsiveness, and personality measures were collected from daily smokers (n=22), nondaily smokers (n=31), and non-smokers (n=30). Results Daily smokers had reduced resting delta and alpha EEG power and higher impulsiveness (Barratt Impulsiveness Scale) compared to nondaily smokers and non-smokers. Both daily and nondaily smokers discounted delayed rewards more steeply, reported lower conscientiousness (NEO-FFI) and reported greater disinhibition and experience seeking (Sensation Seeking Scale) than non-smokers. Nondaily smokers reported greater sensory hedonia than nonsmokers. Conclusions Altered resting EEG power in daily smokers demonstrates differences in neural signaling that correlated with greater smoking behavior and dependence. Although nondaily smokers share some characteristics with daily smokers that may predict smoking initiation and maintenance, they differ on measures of impulsiveness and resting EEG power. Significance Resting EEG in non-deprived chronic smokers provides a standard for comparison to peak and trough nicotine states and may serve as a biomarker for nicotine dependence, relapse risk, and recovery. PMID:26051750

Stability of formation control using a consensus protocol under directed communications with two time delays and delay scheduling

Science.gov (United States)

Cepeda-Gomez, Rudy; Olgac, Nejat

2016-01-01

We consider a linear algorithm to achieve formation control in a group of agents which are driven by second-order dynamics and affected by two rationally independent delays. One of the delays is in the position and the other in the velocity information channels. These delays are taken as constant and uniform throughout the system. The communication topology is assumed to be directed and fixed. The formation is attained by adding a supplementary control term to the stabilising consensus protocol. In preparation for the formation control logic, we first study the stability of the consensus, using the recent cluster treatment of characteristic roots (CTCR) paradigm. This effort results in a unique depiction of the non-conservative stability boundaries in the domain of the delays. However, CTCR requires the knowledge of the potential stability switching loci exhaustively within this domain. The creation of these loci is done in a new surrogate coordinate system, called the 'spectral delay space (SDS)'. The relative stability is also investigated, which has to do with the speed of reaching consensus. This step leads to a paradoxical control design concept, called the 'delay scheduling', which highlights the fact that the group behaviour may be enhanced by increasing the delays. These steps lead to a control strategy to establish a desired group formation that guarantees spacing among the agents. Example case studies are presented to validate the underlying analytical derivations.

Delay-induced wave instabilities in single-species reaction-diffusion systems

Science.gov (United States)

Otto, Andereas; Wang, Jian; Radons, Günter

2017-11-01

The Turing (wave) instability is only possible in reaction-diffusion systems with more than one (two) components. Motivated by the fact that a time delay increases the dimension of a system, we investigate the presence of diffusion-driven instabilities in single-species reaction-diffusion systems with delay. The stability of arbitrary one-component systems with a single discrete delay, with distributed delay, or with a variable delay is systematically analyzed. We show that a wave instability can appear from an equilibrium of single-species reaction-diffusion systems with fluctuating or distributed delay, which is not possible in similar systems with constant discrete delay or without delay. More precisely, we show by basic analytic arguments and by numerical simulations that fast asymmetric delay fluctuations or asymmetrically distributed delays can lead to wave instabilities in these systems. Examples, for the resulting traveling waves are shown for a Fisher-KPP equation with distributed delay in the reaction term. In addition, we have studied diffusion-induced instabilities from homogeneous periodic orbits in the same systems with variable delay, where the homogeneous periodic orbits are attracting resonant periodic solutions of the system without diffusion, i.e., periodic orbits of the Hutchinson equation with time-varying delay. If diffusion is introduced, standing waves can emerge whose temporal period is equal to the period of the variable delay.

Decisions in Motion: Decision Dynamics during Intertemporal Choice reflect Subjective Evaluation of Delayed Rewards

Science.gov (United States)

O'Hora, Denis; Carey, Rachel; Kervick, Aoife; Crowley, David; Dabrowski, Maciej

2016-02-01

People tend to discount rewards or losses that occur in the future. Such delay discounting has been linked to many behavioral and health problems, since people choose smaller short-term gains over greater long-term gains. We investigated whether the effect of delays on the subjective value of rewards is expressed in how people move when they make choices. Over 600 patrons of the RISK LAB exhibition hosted by the Science Gallery DublinTM played a short computer game in which they used a computer mouse to choose between amounts of money at various delays. Typical discounting effects were observed and decision dynamics indicated that choosing smaller short-term rewards became easier (i.e., shorter response times, tighter trajectories, less vacillation) as the delays until later rewards increased. Based on a sequence of choices, subjective values of delayed outcomes were estimated and decision dynamics during initial choices predicted these values. Decision dynamics are affected by subjective values of available options and thus provide a means to estimate such values.

Charging-delay effect on longitudinal dust acoustic shock wave in strongly coupled dusty plasma

International Nuclear Information System (INIS)

Ghosh, Samiran; Gupta, M.R.

2005-01-01

Taking into account the charging-delay effect, the nonlinear propagation characteristics of longitudinal dust acoustic wave in strongly coupled collisional dusty plasma described by generalized hydrodynamic model have been investigated. In the 'hydrodynamic limit', a Korteweg-de Vries Burger (KdVB) equation with a damping term arising due to dust-neutral collision is derived in which the Burger term is proportional to the dissipation due to dust viscosity through dust-dust correlation and charging-delay-induced anomalous dissipation. On the other hand, in the 'kinetic limit', a KdVB equation with a damping term and a nonlocal nonlinear forcing term arising due to memory-dependent strong correlation effect of dust fluid is derived in which the Burger term depends only on the charging-delay-induced dissipation. Numerical solution of integrodifferential equations reveals that (i) dissipation due to dust viscosity and principally due to charging delay causes excitation of the longitudinal dust acoustic shock wave in strongly coupled dusty plasma and (ii) dust-neutral collision does not appear to play any direct role in shock formation. The condition for the generation of shock is also discussed briefly

Delayed Complications and Long-Term Management of Sulfur Mustard Poisoning: A Narrative Review of Recent Advances by Iranian Researchers Part ІІ: Clinical Management and Therapy

Directory of Open Access Journals (Sweden)

Leila Etemad

2018-05-01

Full Text Available The present study aimed to review and discuss the recommended and recently suggested protocols by Iranian researchers for a long-term treatment of delayed complications of sulfur mustard (DCSM in veterans. As indicated clinically, patients who suffer from delayed ocular complications of sulfur mustard (DOCS benefit from treatments for dry eyes, therapeutic contact lenses, amniotic membrane transplantation; blepharorrhaphy, tarsorrhaphy, limbal stem cell transplantation; corneal transplantation, topical steroids, and immunosuppressive. In spite of penetrating keratoplasty, lamellar keratoplasty and keratolimbal allograft had a good long-term survival. Delayed respiratory complications (DRCS are the most common effects and life-threatening in Iranian veterans. The recommended treatment protocols include regular clinical evaluations, respiratory physiotherapy and rehabilitation, N-acetyl cysteine; warm humidified air, long-acting 2-agonists, and inhaled corticosteroids. Azithromycin has also been effective in improving clinical conditions, pulmonary function tests, inflammatory indexes, and life quality of the veterans. Interferon gamma (IFN-γ and helium: oxygen combination were also used in severe DRCS with good results. Some of the delayed cutaneous complications (DCCS such as itching affects the quality of life of victims. Regular but not frequent showering and bathing, applying sunscreen compounds, topical corticosteroids, and systemic antihistamines reduce the problems of DCCS patients. Several compounds such as capsaicin cream, pimecrolimus, IFN-γ, phenol-menthol; Aloe vera/olive oil cream, cetirizine, doxepine, and hydroxyzine were evaluated in DCCS patients with some benefits. The physicians in charge of veterans emphasize the importance of a healthy lifestyle, appropriate financial/social/cultural supports, and a degree of reassurance and supportive care on the clinical improvement of patients.

Stability of neutral type descriptor system with mixed delays

International Nuclear Information System (INIS)

Li Hong; Li Houbiao; Zhong Shouming

2007-01-01

In this paper, the stability problems of general neutral type descriptor system with mixed delays are considered. Some new delay-independent stability and robust stability criteria, which are simpler and less conservative than existing results, are derived in terms of the stability of a new operator I and linear matrix inequalities (LMIs). Therefore, criteria can be easily checked by utilizing the Matlab LMI toolbox

Patients and acute coronary syndrome - Prehospital delay and mental and emotional delaying responses - a qualitative study

DEFF Research Database (Denmark)

Lorentzen, Vibeke; Larsen, Birte Hedegaard

2016-01-01

to identify and discuss patient’s mental and emotional responses, including interpretations and delaying strategies concerning Acute Coronary Syndrome symptoms, with a view to elucidating patterns in the pre-hospital decision-making process of female and male persons to contact medical services...... cardinal. Male participants often used expletives and expressed symptoms in concrete terms. Women expressed symptoms in vaguer terms. Both genders used linguistic metaphors. The implications for nursing emphasised the impact of prodromal symptoms, mental and emotional withdrawal, and linguistic...

Patients and acute coronary syndrome - Prehospital delay and mental and emotional delaying responses - a qualitative study

DEFF Research Database (Denmark)

Lorentzen, Vibeke; Larsen, Birte Hedegaard

2016-01-01

cardinal. Male participants often used expletives and expressed symptoms in concrete terms. Women expressed symptoms in vaguer terms. Both genders used linguistic metaphors. The implications for nursing emphasised the impact of prodromal symptoms, mental and emotional withdrawal, and linguistic...... to identify and discuss patient’s mental and emotional responses, including interpretations and delaying strategies concerning Acute Coronary Syndrome symptoms, with a view to elucidating patterns in the pre-hospital decision-making process of female and male persons to contact medical services...

Wrist activity in a woman: daily, weekly, menstrual, lunar, annual cycles?

Science.gov (United States)

Binkley, S

1992-09-01

Wrist activity was monitored continuously for one year in a woman who went about her normal life. The year of data were analyzed for changes and rhythms--daily, weekly, menstrual, lunar, annual. For each day, average motions/5 minutes, activity onset, activity offset, alpha (duration of activity), and acrophase were measured. Periodograms and average daily wave forms were calculated. Well-defined, entrained, daily rest-activity cycles were observed throughout the year with periods close to 24 hours. There was weekend delay (0.7 hours) in onset, weekend decrease in alpha (1.0 hours), and weekend advance of acrophase (0.4 hours). Motions/5 minutes decreased 9%, onsets were 0.3 hours later, and alphas were 0.4 hours shorter on menstrual cycle days 8 through 18 which should have encompassed the time of ovulation. Lunar phase had no effect. Annual changes in onset (1.1 hours), offset (1.2 hours), and acrophase (1.1 hours) were attributed to the 1-hour change between standard and daylight savings time.

Update of Inpatient Treatment for Refractory Chronic Daily Headache.

Science.gov (United States)

Lai, Tzu-Hsien; Wang, Shuu-Jiun

2016-01-01

Chronic daily headache (CDH) is a group of headache disorders, in which headaches occur daily or near-daily (>15 days per month) and last for more than 3 months. Important CDH subtypes include chronic migraine, chronic tension-type headache, hemicrania continua, and new daily persistent headache. Other headaches with shorter durations (headache and various psychiatric disorders, such as depression and anxiety. Indications of inpatient treatment for CDH patients include poor responses to outpatient management, need for detoxification for overuse of specific medications (particularly opioids and barbiturates), and severe psychiatric comorbidities. Inpatient treatment usually involves stopping acute pain, preventing future attacks, and detoxifying medication overuse if present. Multidisciplinary integrated care that includes medical staff from different disciplines (e.g., psychiatry, clinical psychology, and physical therapy) has been recommended. The outcomes of inpatient treatment are satisfactory in terms of decreasing headache intensity or frequency, withdrawal from medication overuse, reducing disability, and improving life quality, although long-term relapse is not uncommon. In conclusion, inpatient treatment may be useful for select patients with refractory CDH and should be incorporated in a holistic headache care program.

Do Knee Bracing and Delayed Weight Bearing Affect Mid-Term Functional Outcome after Anterior Cruciate Ligament Reconstruction?

Science.gov (United States)

Di Miceli, Riccardo; Marambio, Carlotta Bustos; Zati, Alessandro; Monesi, Roberta; Benedetti, Maria Grazia

2017-12-01

Purpose  The aim of this study was to assess the effect of knee bracing and timing of full weight bearing after anterior cruciate ligament reconstruction (ACLR) on functional outcomes at mid-term follow-up. Methods  We performed a retrospective study on 41 patients with ACLR. Patients were divided in two groups: ACLR group, who received isolated ACL reconstruction and ACLR-OI group who received ACL reconstruction and adjunctive surgery. Information about age at surgery, bracing, full or progressive weight bearing permission after surgery were collected for the two groups. Subjective IKDC score was obtained at follow-up. Statistical analysis was performed to compare the two groups for IKDC score. Subgroup analysis was performed to assess the effect of postoperative regimen (knee bracing and weight bearing) on functional outcomes. Results  The mean age of patients was 30.8 ± 10.6 years. Mean IKDC score was 87.4 ± 13.9. The mean follow-up was 3.5 ± 1.8 years. Twenty-two (53.7%) patients underwent ACLR only, while 19 (46.3%) also received other interventions, such as meniscal repair and/or collateral ligament suture. Analysis of overall data showed no differences between the groups for IKDC score. Patients in the ACLR group exhibited a significantly better IKDC score when no brace and full weight bearing after 4 weeks from surgery was prescribed in comparison with patients who worn a brace and had delayed full weight bearing. No differences were found with respect to the use of brace and postoperative weight bearing regimen in the ACLR-OI group. Conclusion  Brace and delayed weight bearing after ACLR have a negative influence on long-term functional outcomes. Further research is required to explore possible differences in the patients operated on ACLR and other intervention with respect to the use of a brace and the timing of full weight bearing to identify optimal recovery strategies. Level of Evidence  Level III, retrospective observational

Professional ideals and daily practice in journalism

DEFF Research Database (Denmark)

Pihl-Thingvad, Signe

2015-01-01

Professional ideals are crucial in terms of guiding and committing journalists in modern media organizations. But what happens if there are discrepancies between the journalists’ professional ideals and their daily working practice? Research suggests negative consequences, such as withdrawal...

Pinning Synchronization of Delayed Neural Networks with Nonlinear Inner-Coupling

Directory of Open Access Journals (Sweden)

Yangling Wang

2011-01-01

Full Text Available Without assuming the symmetry and irreducibility of the outer-coupling weight configuration matrices, we investigate the pinning synchronization of delayed neural networks with nonlinear inner-coupling. Some delay-dependent controlled stability criteria in terms of linear matrix inequality (LMI are obtained. An example is presented to show the application of the criteria obtained in this paper.

Exponentially convergent state estimation for delayed switched recurrent neural networks.

Science.gov (United States)

Ahn, Choon Ki

2011-11-01

This paper deals with the delay-dependent exponentially convergent state estimation problem for delayed switched neural networks. A set of delay-dependent criteria is derived under which the resulting estimation error system is exponentially stable. It is shown that the gain matrix of the proposed state estimator is characterised in terms of the solution to a set of linear matrix inequalities (LMIs), which can be checked readily by using some standard numerical packages. An illustrative example is given to demonstrate the effectiveness of the proposed state estimator.

Effects of Pre - Season Short - Term Daily Undulating Periodized Training on Muscle Strength and Sprint Performance of Under - 20 Soccer Players

Directory of Open Access Journals (Sweden)

Charles Ricardo L OPES

2015-06-01

Full Text Available The aim of this study was to evaluate the effects of daily undulating training periodization designed for maximal lower limb muscle strength and sprint performance in under - 20 soccer players. Twenty - four male athletes (age = 19.1 ± 1.2 yr; mass = 71.1 ± 6. 8 kg; height = 178.0 ± 0.1 cm participated in four weeks of a daily undulating periodized (DUP training soccer program. During the pre - and post - training periods the subjects performed a one repetition maximum (1 RM half back squat test and a 15 - meter s print. Significant training - induced changes were observed in sprint times (pre = 2.38 ± 0.01 s; post = 2.31 ± 0.02 s and 1 RM tests (pre = 107.0 ± 2.0 kg; post = 128.0 ± 2.2 kg. These results indicate that a DUP program is efficient in promoting positive neuromuscular adaptations in soccer players, even with a short - term preseason training period.

Delayed diagnosis of sarcoidosis is common in Brazil

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Mauri Monteiro Rodrigues

2013-09-01

Full Text Available OBJECTIVE: To determine the frequency of and the factors related to delayed diagnosis of sarcoidosis in Brazil. METHODS: We evaluated patients with a biopsy-proven diagnosis of sarcoidosis, using a questionnaire that addressed the following: time since symptom onset and since the first medical visit; and the number and specialty of the physicians visited. We divided the patients by the timeliness of the diagnosis-timely (< 6 months and delayed (≥ 6 months-comparing the two groups in terms of systemic and pulmonary symptoms; extrathoracic involvement; spirometric data; radiological staging; level of education; income; and tuberculosis (diagnosis and treatment. RESULTS: We evaluated 100 patients. The median number of physicians consulted was 3 (range, 1-14. In 11 cases, sarcoidosis was diagnosed at the first visit. In 54, the first physician seen was a general practitioner. The diagnosis of sarcoidosis was timely in 41 patients and delayed in 59. The groups did not differ in terms of gender; race; type of health insurance; level of education; income; respiratory/systemic symptoms; extrathoracic involvement; and radiological staging. In the delayed diagnosis group, FVC was lower (80.3 ± 20.4% vs. 90.5 ± 17.1%; p = 0.010, as was FEV1 (77.3 ± 19.9% vs. 86.4 ± 19.5%; p = 0.024, misdiagnosis with and treatment for tuberculosis (≥ 3 months also being more common (24% vs. 7%, p = 0.032, and 20% vs. 0%; p = 0.002, respectively. CONCLUSIONS: The diagnosis of sarcoidosis is often delayed, even when the imaging is suggestive of sarcoidosis. Delayed diagnosis is associated with impaired lung function at the time of diagnosis. Many sarcoidosis patients are misdiagnosed with and treated for tuberculosis.

Random Modeling of Daily Rainfall and Runoff Using a Seasonal Model and Wavelet Denoising

Directory of Open Access Journals (Sweden)

Chien-ming Chou

2014-01-01

Full Text Available Instead of Fourier smoothing, this study applied wavelet denoising to acquire the smooth seasonal mean and corresponding perturbation term from daily rainfall and runoff data in traditional seasonal models, which use seasonal means for hydrological time series forecasting. The denoised rainfall and runoff time series data were regarded as the smooth seasonal mean. The probability distribution of the percentage coefficients can be obtained from calibrated daily rainfall and runoff data. For validated daily rainfall and runoff data, percentage coefficients were randomly generated according to the probability distribution and the law of linear proportion. Multiplying the generated percentage coefficient by the smooth seasonal mean resulted in the corresponding perturbation term. Random modeling of daily rainfall and runoff can be obtained by adding the perturbation term to the smooth seasonal mean. To verify the accuracy of the proposed method, daily rainfall and runoff data for the Wu-Tu watershed were analyzed. The analytical results demonstrate that wavelet denoising enhances the precision of daily rainfall and runoff modeling of the seasonal model. In addition, the wavelet denoising technique proposed in this study can obtain the smooth seasonal mean of rainfall and runoff processes and is suitable for modeling actual daily rainfall and runoff processes.

Daily Course of CO2 Fluxes in the Atmosphere-Water System and Variable Fluorescence of Phytoplankton during the Open-Water Period for Lake Baikal according to Long-Term Measurements

Science.gov (United States)

Zavoruev, V. V.; Domysheva, V. M.; Pestunov, D. A.; Sakirko, M. V.; Panchenko, M. V.

2018-04-01

The process of gas exchange of CO2 in the atmosphere-water system and its relation to the daily course of variable fluorescence of phytoplankton is studied on the basis of long-term (2004-2014) measurements during the open water period for Lake Baikal. It is found that the decrease in photosynthetic activity of plankton is almost synchronous to the increase in the CO2 flux from atmosphere to water. It follows from comparison of the spring and summer data with December measurements that the daily decrease in variable fluorescence of phytoplankton is caused by the internal daily rhythm of the photosynthetic activity of plankton.

Study of delayed strains for concrete in compression and in tension from early age to long term

International Nuclear Information System (INIS)

Hilaire, Adrien

2014-01-01

these two phenomenons. The second part is about the delayed strains in concrete. Unlike the conventional decomposition of these strains, creep and shrinkage are correlated and influence the damage evolution. Mechanics of unsaturated porous media is used to consider the couplings between these strains. The last part is focused on the delayed behaviour of structures. Results highlight the importance of some technological barriers in order to predict accurately the long-term behaviour of a containment building. (author)

Short-term and long-term memory in early temporal lobe dysfunction.

Science.gov (United States)

Hershey, T; Craft, S; Glauser, T A; Hale, S

1998-01-01

Following medial temporal damage, mature humans are impaired in retaining new information over long delays but not short delays. The question of whether a similar dissociation occurs in children was addressed by testing children (ages 7-16) with unilateral temporal lobe epilepsy (TLE) and controls on short- and long-term memory tasks, including a spatial delayed response task (SDR). Early-onset TLE did not affect performance on short delays on SDR, but it did impair performance at the longest delay (60 s), similar to adults with unilateral medial temporal damage. In addition, early-onset TLE affected performance on pattern recall, spatial span, and verbal span with rehearsal interference. No differences were found on story recall or on a response inhibition task.

Delayed egg hatching of Anopheles gambiae (Diptera: Culicidae) pending water agitation.

Science.gov (United States)

Ebrahimi, Babak; Shakibi, Sanam; Foster, Woodbridge A

2014-05-01

Mosquito eggs laid on water surfaces typically hatch spontaneously soon after the embryos within them become fully formed first-instar larvae. However, we have found that Anopheles gambiae Giles, an important vector of malaria in Africa, exhibits delayed hatching until the water surface is agitated, a feature overlooked in most laboratory colonies. Agitation within 24 h postoviposition, before embryonation was complete, failed to stimulate delayed postembryonic hatching of isolated eggs on the following day (day 2), when < 1% had hatched spontaneously. However, 5 min of water agitation of these dormant pharate first-instar larvae on day 2 resulted in an almost immediate hatch of 63.3 versus 0% of nonagitated controls, plus another 3.9 versus 0.3%, respectively, during the following 24 h. With daily agitation, installment hatching occurred mainly during 2-6 d postoviposition. The mean cumulative hatch after 7 d of daily agitation was 83.1 versus 1.1% of nonagitated eggs. Experiments with eggs in groups demonstrated that egg density and activity of already-hatched larvae had no stimulatory effect. Eggs stored 1-4 wk at 25.5 or at 15.5 degrees C, and then agitated daily for 6 d at 25.5 degrees C, showed a gradual decline in viability. Viability was sustained longer at the lower temperature. Implications of agitation-induced egg hatching for rainy-season and dry-season ecology of An. gambiae are discussed. Suspended hatching and cool storage already are proving convenient for efficient mass rearing and accurate modeling of weather-based population dynamics.

Radio resource allocation over fading channels under statistical delay constraints

CERN Document Server

Le-Ngoc, Tho

2017-01-01

This SpringerBrief presents radio resource allocation schemes for buffer-aided communications systems over fading channels under statistical delay constraints in terms of upper-bounded average delay or delay-outage probability. This Brief starts by considering a source-destination communications link with data arriving at the source transmission buffer. The first scenario, the joint optimal data admission control and power allocation problem for throughput maximization is considered, where the source is assumed to have a maximum power and an average delay constraints. The second scenario, optimal power allocation problems for energy harvesting (EH) communications systems under average delay or delay-outage constraints are explored, where the EH source harvests random amounts of energy from renewable energy sources, and stores the harvested energy in a battery during data transmission. Online resource allocation algorithms are developed when the statistical knowledge of the random channel fading, data arrivals...

Charging-delay induced dust acoustic collisionless shock wave: Roles of negative ions

International Nuclear Information System (INIS)

Ghosh, Samiran; Bharuthram, R.; Khan, Manoranjan; Gupta, M. R.

2006-01-01

The effects of charging-delay and negative ions on nonlinear dust acoustic waves are investigated. It has been found that the charging-delay induced anomalous dissipation causes generation of dust acoustic collisionless shock waves in an electronegative dusty plasma. The small but finite amplitude wave is governed by a Korteweg-de Vries Burger equation in which the Burger term arises due to the charging-delay. Numerical investigations reveal that the charging-delay induced dissipation and shock strength decreases (increases) with the increase of negative ion concentration (temperature)

Effect of state-dependent delay on a weakly damped nonlinear oscillator.

Science.gov (United States)

Mitchell, Jonathan L; Carr, Thomas W

2011-04-01

We consider a weakly damped nonlinear oscillator with state-dependent delay, which has applications in models for lasers, epidemics, and microparasites. More generally, the delay-differential equations considered are a predator-prey system where the delayed term is linear and represents the proliferation of the predator. We determine the critical value of the delay that causes the steady state to become unstable to periodic oscillations via a Hopf bifurcation. Using asymptotic averaging, we determine how the system's behavior is influenced by the functional form of the state-dependent delay. Specifically, we determine whether the branch of periodic solutions will be either sub- or supercritical as well as an accurate estimation of the amplitude. Finally, we choose a few examples of state-dependent delay to test our analytical results by comparing them to numerical continuation.

Long-term maintenance of immediate or delayed extinction is determined by the extinction-test interval

OpenAIRE

Johnson, Justin S.; Escobar, Martha; Kimble, Whitney L.

2010-01-01

Short acquisition-extinction intervals (immediate extinction) can lead to either more or less spontaneous recovery than long acquisition-extinction intervals (delayed extinction). Using rat subjects, we observed less spontaneous recovery following immediate than delayed extinction (Experiment 1). However, this was the case only if a relatively long extinction-test interval was used; a relatively short extinction-test interval yielded the opposite result (Experiment 2). Previous data appear co...

Daily mortality and air pollutants: findings from Köln, Germany.

Science.gov (United States)

Spix, C; Wichmann, H E

1996-04-01

For the APHEA study, the short term effects of air pollutants on human health were investigated in a comparable way in various European cities. Daily mortality was used as one of the health effects indicators. This report aims to demonstrate the steps in epidemiological model building in this type of time series analysis aimed at detecting short term effects under a poisson distribution assumption and shows the tools for decision making. In addition, it assesses the impact of these steps on the pollution effect estimates. Köln, Germany, is a city of one million inhabitants. It is densely populated with a warm, humid, unfavourable climate and a high traffic density. In previous studies, smog episodes were found to increase mortality and higher sulphur dioxide (SO2) levels were connected with increases in the number of episodes of croup. Daily total mortality was obtained for 1975-85. SO2, total suspended particulates, and nitrogen dioxide (NO2) data were available from two to five stations for the city area, and size fractionated PM7 data from a neighbouring city. The main tools were time series plots of the raw data, predicted and residual data, the partial autocorrelation function and periodogram of the residuals, cross correlations of prefiltered series, plots of categorised influences, chi 2 statistics of influences and sensitivity analyses taking overdispersion and autocorrelation into account. With regard to model building, it is concluded that seasonal and epidemic correction are the most important steps. The actual model chosen depends very much on the properties of the data set. For the pollution effect estimates, trend, season, and epidemic corrections are important to avoid overestimation of the effect, while an appropriate short term meterology influence correction model may actually prevent underestimation. When the model leaves very little over-dispersion and autocorrelation in the residuals, which indicates a good fit, correction for them has

Analytical Solution of Pantograph Equation with Incommensurate Delay

Science.gov (United States)

Patade, Jayvant; Bhalekar, Sachin

2017-08-01

Pantograph equation is a delay differential equation (DDE) arising in electrodynamics. This paper studies the pantograph equation with two delays. The existence, uniqueness, stability and convergence results for DDEs are presented. The series solution of the proposed equation is obtained by using Daftardar-Gejji and Jafari method and given in terms of a special function. This new special function has several properties and relations with other functions. Further, we generalize the proposed equation to fractional-order case and obtain its solution.

Optimal Joint Expected Delay Forwarding in Delay Tolerant Networks

OpenAIRE

Jia Xu; Xin Feng; Wen Jun Yang; Ru Chuan Wang; Bing Qing Han

2013-01-01

Multicopy forwarding schemes have been employed in delay tolerant network (DTN) to improve the delivery delay and delivery rate. Much effort has been focused on reducing the routing cost while retaining high performance. This paper aims to provide an optimal joint expected delay forwarding (OJEDF) protocol which minimizes the expected delay while satisfying a certain constant on the number of forwardings per message. We propose a comprehensive forwarding metric called joint expected delay (JE...

Daily and seasonal variation of short-lived radon decay product concentrations in ground-level air at Munich-Neuherberg - a long-term study

International Nuclear Information System (INIS)

Winkler, R.

2001-09-01

Daily and seasonal variation of the equilibrium equivalent radon concentration (EEC Rn-222 ) and of the concentration of the short-lived radon decay product 214 Pb in ground-level air was investigated at Munich-Neuherberg from 1982 to 2000, and from 1989 to 2000, respectively. For this, the EEC was measured continuously with an alpha/beta aerosol monitor at 2.5 m above ground, and 214 Pb was determined by online gamma spectrometry at about 12 m above ground. The resulting time series were analysed statistically. For the respective periods, the measurements yielded a long-term average concentration of 7.8 Bq m -3 (geometric mean: 6.1 Bq m -3 ) for the EEC, and 6.0 Bq m -3 (geom. mean: 5.0 Bq m -3 ) for 214 Pb. In these periods, daily averages ranged from 0.6 to 49 Bq m -3 (EEC), and from 0.6 to 43 Bq m -3 ( 214 Pb). Monthly mean concentrations varied between 3.0 Bq m -3 in March 1988 and 20 Bq m -3 in October 1985 (EEC), and from 3.4 Bq m -3 in April 1992 to 11 Bq m -3 in October 1995 ( 214 Pb), respectively. The annual average concentrations were from 5.9 Bq m -3 in 1999 to 10.6 Bq m -3 in 1985 (EEC), and from 5.3 Bq m -3 in 1999 to 6.8 Bq m -3 in 1991 ( 214 Pb). From the long-term average equilibrium equivalent radon concentration (EEC), an average annual effective dose of 0.13 mSv due to the short-lived radon progeny outdoors was estimated. The time series showed distinct daily and seasonal variations. The variations from day to day are mainly caused by the actual weather conditions (wind, rain, etc.), i.e. the short-term turbulent conditions. The seasonal pattern is characterised by an autumn to winter maximum and an early summer minimum, and reflects the prevailing turbulent conditions at the respective seasons. As known, at Munich-Neuherberg during autumn and winter months (October/November to February) inversion weather conditions frequently occur, while the other months are characterised by more turbulent conditions. (orig.)

Selected aspects in the structure of beta-delayed particle spectra

International Nuclear Information System (INIS)

Honkanen, J.; Aeystoe, J.; Eskola, K.

1986-01-01

Some weak beta-delayed particle emitters in the T z =-3/2, -1, -1/2, +1/2 and +5/2 series are reviewed. Selected features of the delayed particle emission are discussed in terms of experimental delayed particle data and (p,γ), (p,p') and (p,n) reaction data. Experimental beta transition strengths are compared with the existing complete shell-model calculations for the sd-shell nuclei. The effect of the Gamow-Teller giant resonance on the structure of the delayed particle spectra is considered. The correlation between the widths of two decay channels, protons and alpha particles, and the preceeding beta decay is studied in the case of the 40 Sc decay. (orig.)

Second-order differential-delay equation to describe a hybrid bistable device

Science.gov (United States)

Vallee, R.; Dubois, P.; Cote, M.; Delisle, C.

1987-08-01

The problem of a dynamical system with delayed feedback, a hybrid bistable device, characterized by n response times and described by an nth-order differential-delay equation (DDE) is discussed. Starting from a linear-stability analysis of the DDE, the effects of the second-order differential terms on the position of the first bifurcation and on the frequency of the resulting self-oscillation are shown. The effects of the third-order differential terms on the first bifurcation are also considered. Experimental results are shown to support the linear analysis.

Opportunities for Process Monitoring Techniques at Delayed Access Facilities

Energy Technology Data Exchange (ETDEWEB)

Curtis, Michael M.; Gitau, Ernest TN; Johnson, Shirley J.; Schanfein, Mark; Toomey, Christopher

2013-09-20

Except for specific cases where the International Atomic Energy Agency (IAEA) maintains a continuous presence at a facility (such as the Japanese Rokkasho Reprocessing Plant), there is always a period of time or delay between the moment a State is notified or aware of an upcoming inspection, and the time the inspector actually enters the material balance area or facility. Termed by the authors as “delayed access,” this period of time between inspection notice and inspector entrance to a facility poses a concern. Delayed access also has the potential to reduce the effectiveness of measures applied as part of the Safeguards Approach for a facility (such as short-notice inspections). This report investigates the feasibility of using process monitoring to address safeguards challenges posed by delayed access at a subset of facility types.

The grateful are patient: Heightened daily gratitude is associated with attenuated temporal discounting.

Science.gov (United States)

Dickens, Leah; DeSteno, David

2016-06-01

Past research has regularly linked the experience of affect to increased impatience and, thereby, decreased self-control. Given emerging work identifying the emotion gratitude as a fairly unique affective state capable of enhancing, rather than inhibiting, patience, the present study examined the association between chronically elevated gratitude and individual differences in temporal discounting. Participants' levels of gratitude were assessed in response to a standardized lab induction and then over a 3-week period prior to measurement of their financial patience in the form of an incentivized delay discounting task. Analyses revealed a strong relation between lab-based and naturally occurring gratitude levels, thereby confirming the validity of the daily online measures. Of import, mean levels of daily gratitude were significantly associated with increased patience in the form of decreased temporal discounting. As expected, no similar relation emerged for daily levels of happiness, thereby confirming the relative specificity of the positive state of gratitude. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Robust stability of bidirectional associative memory neural networks with time delays

Science.gov (United States)

Park, Ju H.

2006-01-01

Based on the Lyapunov Krasovskii functionals combined with linear matrix inequality approach, a novel stability criterion is proposed for asymptotic stability of bidirectional associative memory neural networks with time delays. A novel delay-dependent stability criterion is given in terms of linear matrix inequalities, which can be solved easily by various optimization algorithms.

Robust stability of bidirectional associative memory neural networks with time delays

International Nuclear Information System (INIS)

Park, Ju H.

2006-01-01

Based on the Lyapunov-Krasovskii functionals combined with linear matrix inequality approach, a novel stability criterion is proposed for asymptotic stability of bidirectional associative memory neural networks with time delays. A novel delay-dependent stability criterion is given in terms of linear matrix inequalities, which can be solved easily by various optimization algorithms

Distributed optimisation problem with communication delay and external disturbance

Science.gov (United States)

Tran, Ngoc-Tu; Xiao, Jiang-Wen; Wang, Yan-Wu; Yang, Wu

2017-12-01

This paper investigates the distributed optimisation problem for the multi-agent systems (MASs) with the simultaneous presence of external disturbance and the communication delay. To solve this problem, a two-step design scheme is introduced. In the first step, based on the internal model principle, the internal model term is constructed to compensate the disturbance asymptotically. In the second step, a distributed optimisation algorithm is designed to solve the distributed optimisation problem based on the MASs with the simultaneous presence of disturbance and communication delay. Moreover, in the proposed algorithm, each agent interacts with its neighbours through the connected topology and the delay occurs during the information exchange. By utilising Lyapunov-Krasovskii functional, the delay-dependent conditions are derived for both slowly and fast time-varying delay, respectively, to ensure the convergence of the algorithm to the optimal solution of the optimisation problem. Several numerical simulation examples are provided to illustrate the effectiveness of the theoretical results.

Maximum likelihood window for time delay estimation

International Nuclear Information System (INIS)

Lee, Young Sup; Yoon, Dong Jin; Kim, Chi Yup

2004-01-01

Time delay estimation for the detection of leak location in underground pipelines is critically important. Because the exact leak location depends upon the precision of the time delay between sensor signals due to leak noise and the speed of elastic waves, the research on the estimation of time delay has been one of the key issues in leak lovating with the time arrival difference method. In this study, an optimal Maximum Likelihood window is considered to obtain a better estimation of the time delay. This method has been proved in experiments, which can provide much clearer and more precise peaks in cross-correlation functions of leak signals. The leak location error has been less than 1 % of the distance between sensors, for example the error was not greater than 3 m for 300 m long underground pipelines. Apart from the experiment, an intensive theoretical analysis in terms of signal processing has been described. The improved leak locating with the suggested method is due to the windowing effect in frequency domain, which offers a weighting in significant frequencies.

Short-term pre- and post-operative stress prolongs incision-induced pain hypersensitivity without changing basal pain perception.

Science.gov (United States)

Cao, Jing; Wang, Po-Kai; Tiwari, Vinod; Liang, Lingli; Lutz, Brianna Marie; Shieh, Kun-Ruey; Zang, Wei-Dong; Kaufman, Andrew G; Bekker, Alex; Gao, Xiao-Qun; Tao, Yuan-Xiang

2015-12-02

Chronic stress has been reported to increase basal pain sensitivity and/or exacerbate existing persistent pain. However, most surgical patients have normal physiological and psychological health status such as normal pain perception before surgery although they do experience short-term stress during pre- and post-operative periods. Whether or not this short-term stress affects persistent postsurgical pain is unclear. In this study, we showed that pre- or post-surgical exposure to immobilization 6 h daily for three consecutive days did not change basal responses to mechanical, thermal, or cold stimuli or peak levels of incision-induced hypersensitivity to these stimuli; however, immobilization did prolong the duration of incision-induced hypersensitivity in both male and female rats. These phenomena were also observed in post-surgical exposure to forced swimming 25 min daily for 3 consecutive days. Short-term stress induced by immobilization was demonstrated by an elevation in the level of serum corticosterone, an increase in swim immobility, and a decrease in sucrose consumption. Blocking this short-term stress via intrathecal administration of a selective glucocorticoid receptor antagonist, RU38486, or bilateral adrenalectomy significantly attenuated the prolongation of incision-induced hypersensitivity to mechanical, thermal, and cold stimuli. Our results indicate that short-term stress during the pre- or post-operative period delays postoperative pain recovery although it does not affect basal pain perception. Prevention of short-term stress may facilitate patients' recovery from postoperative pain.

Electrocardiogram classification using delay differential equations.

Science.gov (United States)

Lainscsek, Claudia; Sejnowski, Terrence J

2013-06-01

Time series analysis with nonlinear delay differential equations (DDEs) reveals nonlinear as well as spectral properties of the underlying dynamical system. Here, global DDE models were used to analyze 5 min data segments of electrocardiographic (ECG) recordings in order to capture distinguishing features for different heart conditions such as normal heart beat, congestive heart failure, and atrial fibrillation. The number of terms and delays in the model as well as the order of nonlinearity of the model have to be selected that are the most discriminative. The DDE model form that best separates the three classes of data was chosen by exhaustive search up to third order polynomials. Such an approach can provide deep insight into the nature of the data since linear terms of a DDE correspond to the main time-scales in the signal and the nonlinear terms in the DDE are related to nonlinear couplings between the harmonic signal parts. The DDEs were able to detect atrial fibrillation with an accuracy of 72%, congestive heart failure with an accuracy of 88%, and normal heart beat with an accuracy of 97% from 5 min of ECG, a much shorter time interval than required to achieve comparable performance with other methods.

New Delay-Dependent Robust Exponential Stability Criteria of LPD Neutral Systems with Mixed Time-Varying Delays and Nonlinear Perturbations

Directory of Open Access Journals (Sweden)

Sirada Pinjai

2013-01-01

Full Text Available This paper is concerned with the problem of robust exponential stability for linear parameter-dependent (LPD neutral systems with mixed time-varying delays and nonlinear perturbations. Based on a new parameter-dependent Lyapunov-Krasovskii functional, Leibniz-Newton formula, decomposition technique of coefficient matrix, free-weighting matrices, Cauchy’s inequality, modified version of Jensen’s inequality, model transformation, and linear matrix inequality technique, new delay-dependent robust exponential stability criteria are established in terms of linear matrix inequalities (LMIs. Numerical examples are given to show the effectiveness and less conservativeness of the proposed methods.

fMRI study of neural sensitization to hedonic stimuli in long‐term, daily cannabis users

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Dunlop, Joseph; Ketcherside, Ariel; Baine, Jessica; Rhinehardt, Tyler; Kuhn, Brittany; DeWitt, Sam; Alvi, Talha

2016-01-01

Abstract Although there is emergent evidence illustrating neural sensitivity to cannabis cues in cannabis users, the specificity of this effect to cannabis cues as opposed to a generalized hyper‐sensitivity to hedonic stimuli has not yet been directly tested. Using fMRI, we presented 53 daily, long‐term cannabis users and 68 non‐using controls visual and tactile cues for cannabis, a natural reward, and, a sensory‐perceptual control object to evaluate brain response to hedonic stimuli in cannabis users. The results showed an interaction between group and reward type such that the users had greater response during cannabis cues relative to natural reward cues (i.e., fruit) in the orbitofrontal cortex, striatum, anterior cingulate gyrus, and ventral tegmental area compared to non‐users (cluster‐threshold z = 2.3, P cannabis cues in fronto‐striatal‐temporal regions and subjective craving, marijuana‐related problems, withdrawal symptoms, and levels of THC metabolites (cluster‐threshold z = 2.3, P cannabis cues in long‐term cannabis users that are above that of response to natural reward cues. These observations are concordant with incentive sensitization models suggesting sensitization of mesocorticolimbic regions and disruption of natural reward processes following drug use. Although the cross‐sectional nature of this study does not provide information on causality, the positive correlations between neural response and indicators of cannabis use (i.e., THC levels) suggest that alterations in the reward system are, in part, related to cannabis use. Hum Brain Mapp 37:3431–3443, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:27168331

Global Historical Climatology Network - Daily (GHCN-Daily), Version 3

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National Oceanic and Atmospheric Administration, Department of Commerce — The Global Historical Climatology Network - Daily (GHCN-Daily) dataset integrates daily climate observations from approximately 30 different data sources. Version 3...

Stability analysis of delayed genetic regulatory networks with stochastic disturbances

Energy Technology Data Exchange (ETDEWEB)

Zhou Qi, E-mail: zhouqilhy@yahoo.com.c [School of Automation, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu (China); Xu Shengyuan [School of Automation, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu (China); Chen Bing [Institute of Complexity Science, Qingdao University, Qingdao 266071, Shandong (China); Li Hongyi [Space Control and Inertial Technology Research Center, Harbin Institute of Technology, Harbin 150001 (China); Chu Yuming [Department of Mathematics, Huzhou Teacher' s College, Huzhou 313000, Zhejiang (China)

2009-10-05

This Letter considers the problem of stability analysis of a class of delayed genetic regulatory networks with stochastic disturbances. The delays are assumed to be time-varying and bounded. By utilizing Ito's differential formula and Lyapunov-Krasovskii functionals, delay-range-dependent and rate-dependent (rate-independent) stability criteria are proposed in terms of linear matrices inequalities. An important feature of the proposed results is that all the stability conditions are dependent on the upper and lower bounds of the delays. Another important feature is that the obtained stability conditions are less conservative than certain existing ones in the literature due to introducing some appropriate free-weighting matrices. A simulation example is employed to illustrate the applicability and effectiveness of the proposed methods.

Nonlinear smith-predictor based control strategy for a unicycle mobile robot subject to transport delay

NARCIS (Netherlands)

Alvarez Aguirre, A.; Velasco-Villa, M.; Del Muro Cuellar, B.

2008-01-01

This paper consider the remote control of an unicycle mobile robot subject to transport delay. The communication delay effects are considered by means of a discrete time approach that allows to solve the path tracking problem in terms of the delayed input. The causality problem involved in the

Geometric methods of global attraction in systems of delay differential equations

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El-Morshedy, Hassan A.; Ruiz-Herrera, Alfonso

2017-11-01

In this paper we deduce criteria of global attraction in systems of delay differential equations. Our methodology is new and consists in "dominating" the nonlinear terms of the system by a scalar function and then studying some dynamical properties of that function. One of the crucial benefits of our approach is that we obtain delay-dependent results of global attraction that cover the best delay-independent conditions. We apply our results in a gene regulatory model and the classical Nicholson's blowfly equation with patch structure.

Dynamics of a viral infection model with delayed CTL response and immune circadian rhythm

International Nuclear Information System (INIS)

Bai Zhenguo; Zhou Yicang

2012-01-01

This paper studies the global dynamics of a viral infection model that takes into account circadian rhythm and time delay in the CTL response. It is shown that the basic reproduction numbers, R 0 and R 1 , determine the outcome of viral infection. Numerical simulations demonstrate that the changes in the amplitude of lytic component can generate a variety of dynamical patterns, ranging from simple daily oscillation to multi-day dynamics and eventually chaos, whereas time delay can alter the period of oscillation for the larger level of periodic forcing. These results can help to explain the viral oscillation behaviors, which were observed in chronic HBV and HCV infection patients.

General relation between the group delay and dwell time in multicomponent electron systems

Science.gov (United States)

Zhai, Feng; Lu, Junqiang

2016-10-01

For multicomponent electron scattering states, we derive a general relation between the Wigner group delay and the Bohmian dwell time. It is found that the definition of group delay should account for the phase of the spinor wave functions of propagating modes. The difference between the group delay and dwell time comes from both the interference delay and the decaying modes. For barrier tunneling of helical electrons on a surface of topological insulators, our calculations including the trigonal-warping term show that the decaying modes can contribute greatly to the group delay. The derived relation between the group delay and the dwell time is helpful to unify the two definitions of tunneling time in a quite general situation.

Global synchronization of a class of delayed complex networks

International Nuclear Information System (INIS)

Li Ping; Yi Zhang; Zhang Lei

2006-01-01

Global synchronization of a class of complex networks with time-varying delays is investigated in this paper. Some sufficient conditions are derived. These conditions show that the synchronization of delayed complex networks can be determined by their topologies. In addition, these conditions are simply represented in terms of the networks coupling matrix and are easy to be checked. A typical example of complex networks with chaotic nodes is employed to illustrate the obtained global synchronization results

A Novel Hybrid Data-Driven Model for Daily Land Surface Temperature Forecasting Using Long Short-Term Memory Neural Network Based on Ensemble Empirical Mode Decomposition

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Xike Zhang

2018-05-01

Full Text Available Daily land surface temperature (LST forecasting is of great significance for application in climate-related, agricultural, eco-environmental, or industrial studies. Hybrid data-driven prediction models using Ensemble Empirical Mode Composition (EEMD coupled with Machine Learning (ML algorithms are useful for achieving these purposes because they can reduce the difficulty of modeling, require less history data, are easy to develop, and are less complex than physical models. In this article, a computationally simple, less data-intensive, fast and efficient novel hybrid data-driven model called the EEMD Long Short-Term Memory (LSTM neural network, namely EEMD-LSTM, is proposed to reduce the difficulty of modeling and to improve prediction accuracy. The daily LST data series from the Mapoling and Zhijaing stations in the Dongting Lake basin, central south China, from 1 January 2014 to 31 December 2016 is used as a case study. The EEMD is firstly employed to decompose the original daily LST data series into many Intrinsic Mode Functions (IMFs and a single residue item. Then, the Partial Autocorrelation Function (PACF is used to obtain the number of input data sample points for LSTM models. Next, the LSTM models are constructed to predict the decompositions. All the predicted results of the decompositions are aggregated as the final daily LST. Finally, the prediction performance of the hybrid EEMD-LSTM model is assessed in terms of the Mean Square Error (MSE, Mean Absolute Error (MAE, Mean Absolute Percentage Error (MAPE, Root Mean Square Error (RMSE, Pearson Correlation Coefficient (CC and Nash-Sutcliffe Coefficient of Efficiency (NSCE. To validate the hybrid data-driven model, the hybrid EEMD-LSTM model is compared with the Recurrent Neural Network (RNN, LSTM and Empirical Mode Decomposition (EMD coupled with RNN, EMD-LSTM and EEMD-RNN models, and their comparison results demonstrate that the hybrid EEMD-LSTM model performs better than the other

A Novel Hybrid Data-Driven Model for Daily Land Surface Temperature Forecasting Using Long Short-Term Memory Neural Network Based on Ensemble Empirical Mode Decomposition.

Science.gov (United States)

Zhang, Xike; Zhang, Qiuwen; Zhang, Gui; Nie, Zhiping; Gui, Zifan; Que, Huafei

2018-05-21

Daily land surface temperature (LST) forecasting is of great significance for application in climate-related, agricultural, eco-environmental, or industrial studies. Hybrid data-driven prediction models using Ensemble Empirical Mode Composition (EEMD) coupled with Machine Learning (ML) algorithms are useful for achieving these purposes because they can reduce the difficulty of modeling, require less history data, are easy to develop, and are less complex than physical models. In this article, a computationally simple, less data-intensive, fast and efficient novel hybrid data-driven model called the EEMD Long Short-Term Memory (LSTM) neural network, namely EEMD-LSTM, is proposed to reduce the difficulty of modeling and to improve prediction accuracy. The daily LST data series from the Mapoling and Zhijaing stations in the Dongting Lake basin, central south China, from 1 January 2014 to 31 December 2016 is used as a case study. The EEMD is firstly employed to decompose the original daily LST data series into many Intrinsic Mode Functions (IMFs) and a single residue item. Then, the Partial Autocorrelation Function (PACF) is used to obtain the number of input data sample points for LSTM models. Next, the LSTM models are constructed to predict the decompositions. All the predicted results of the decompositions are aggregated as the final daily LST. Finally, the prediction performance of the hybrid EEMD-LSTM model is assessed in terms of the Mean Square Error (MSE), Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), Root Mean Square Error (RMSE), Pearson Correlation Coefficient (CC) and Nash-Sutcliffe Coefficient of Efficiency (NSCE). To validate the hybrid data-driven model, the hybrid EEMD-LSTM model is compared with the Recurrent Neural Network (RNN), LSTM and Empirical Mode Decomposition (EMD) coupled with RNN, EMD-LSTM and EEMD-RNN models, and their comparison results demonstrate that the hybrid EEMD-LSTM model performs better than the other five

Synchronization of stochastic delayed neural networks with markovian switching and its application.

Science.gov (United States)

Tang, Yang; Fang, Jian-An; Miao, Qing-Ying

2009-02-01

In this paper, the problem of adaptive synchronization for a class of stochastic neural networks (SNNs) which involve both mixed delays and Markovian jumping parameters is investigated. The mixed delays comprise the time-varying delays and distributed delays, both of which are mode-dependent. The stochastic perturbations are described in terms of Browian motion. By the adaptive feedback technique, several sufficient criteria have been proposed to ensure the synchronization of SNNs in mean square. Moreover, the proposed adaptive feedback scheme is applied to the secure communication. Finally, the corresponding simulation results are given to demonstrate the usefulness of the main results obtained.

Stability and delay sensitivity of neutral fractional-delay systems.

Science.gov (United States)

Xu, Qi; Shi, Min; Wang, Zaihua

2016-08-01

This paper generalizes the stability test method via integral estimation for integer-order neutral time-delay systems to neutral fractional-delay systems. The key step in stability test is the calculation of the number of unstable characteristic roots that is described by a definite integral over an interval from zero to a sufficient large upper limit. Algorithms for correctly estimating the upper limits of the integral are given in two concise ways, parameter dependent or independent. A special feature of the proposed method is that it judges the stability of fractional-delay systems simply by using rough integral estimation. Meanwhile, the paper shows that for some neutral fractional-delay systems, the stability is extremely sensitive to the change of time delays. Examples are given for demonstrating the proposed method as well as the delay sensitivity.

Does Daily Distress Make Parents Prone to Using Psychologically Controlling Parenting?

Science.gov (United States)

Aunola, Kaisa; Viljaranta, Jaana; Tolvanen, Asko

2017-01-01

The aim of the present study was to investigate whether parental daily distress in terms of negative emotions is associated with the daily variation in parental use of psychological control with their children. Whether parental positive emotions play a role in the use of psychological control was also investigated. The participants were 149…

Exponential stability of delayed fuzzy cellular neural networks with diffusion

International Nuclear Information System (INIS)

Huang Tingwen

2007-01-01

The exponential stability of delayed fuzzy cellular neural networks (FCNN) with diffusion is investigated. Exponential stability, significant for applications of neural networks, is obtained under conditions that are easily verified by a new approach. Earlier results on the exponential stability of FCNN with time-dependent delay, a special case of the model studied in this paper, are improved without using the time-varying term condition: dτ(t)/dt < μ

Aging transition in systems of oscillators with global distributed-delay coupling.

Science.gov (United States)

Rahman, B; Blyuss, K B; Kyrychko, Y N

2017-09-01

We consider a globally coupled network of active (oscillatory) and inactive (nonoscillatory) oscillators with distributed-delay coupling. Conditions for aging transition, associated with suppression of oscillations, are derived for uniform and gamma delay distributions in terms of coupling parameters and the proportion of inactive oscillators. The results suggest that for the uniform distribution increasing the width of distribution for the same mean delay allows aging transition to happen for a smaller coupling strength and a smaller proportion of inactive elements. For gamma distribution with sufficiently large mean time delay, it may be possible to achieve aging transition for an arbitrary proportion of inactive oscillators, as long as the coupling strength lies in a certain range.

Event-Triggered Faults Tolerant Control for Stochastic Systems with Time Delays

Directory of Open Access Journals (Sweden)

Ling Huang

2016-01-01

Full Text Available This paper is concerned with the state-feedback controller design for stochastic networked control systems (NCSs with random actuator failures and transmission delays. Firstly, an event-triggered scheme is introduced to optimize the performance of the stochastic NCSs. Secondly, stochastic NCSs under event-triggered scheme are modeled as stochastic time-delay systems. Thirdly, some less conservative delay-dependent stability criteria in terms of linear matrix inequalities for the codesign of both the controller gain and the trigger parameters are obtained by using delay-decomposition technique and convex combination approach. Finally, a numerical example is provided to show the less sampled data transmission and less conservatism of the proposed theory.

Effect of magnesium treatment and glucose levels on delayed cerebral ischemia in patients with subarachnoid hemorrhage: a substudy of the Magnesium in Aneurysmal Subarachnoid Haemorrhage trial (MASH-II).

Science.gov (United States)

Leijenaar, Jolien F; Dorhout Mees, Sanne M; Algra, Ale; van den Bergh, Walter M; Rinkel, Gabriel J E

2015-10-01

Magnesium treatment did not improve outcome in patients with aneurysmal subarachnoid haemorrhage in the Magnesium in Aneurysmal Subarachnoid Haemorrhage II trial. We hypothesized that high glucose levels may have offset a potential beneficial effect to prevent delayed cerebral ischemia. We investigated if magnesium treatment led to less delayed cerebral ischemia and if glucose levels interacted with magnesium treatment in the Magnesium in Aneurysmal Subarachnoid Haemorrhage II trial. To investigate the effect of magnesium treatment on occurrence of delayed cerebral ischemia and the interaction between glucose levels and magnesium treatment in subarachnoid hemorrhage patients. The Magnesium in Aneurysmal Subarachnoid Haemorrhage was a phase III randomized placebo-controlled trial assessing the effect of magnesium sulphate on clinical outcome in aneurysmal subarachnoid hemorrhage patients. For the current study, we included only the patients admitted to the University Medical Centre-Utrecht. We calculated hazard ratios for occurrence of delayed cerebral ischemia in patients treated with magnesium vs. placebo for the entire study population, and separately in the subgroups of patients with high and low mean fasting and mean daily glucose levels until onset of delayed cerebral ischemia. We used the cross-product of magnesium and glucose in the regression analysis to evaluate whether an interaction between magnesium and glucose existed. We included 616 patients: 307 received magnesium and 309 placebo; 156 patients had delayed cerebral ischemia. Hazard ratio for magnesium on occurrence of delayed cerebral ischemia was 1·0 (95% confidence interval: 0·7-1·4). Results were similar in patients with low or high fasting or daily glucose levels. We found no interactions between magnesium treatment and high fasting (P = 0·54) and daily glucose (P = 0·60). Magnesium treatment did not reduce the risk of delayed cerebral ischemia in patients with aneurysmal

The influence of delaying judgments of learning on metacognitive accuracy: a meta-analytic review.

Science.gov (United States)

Rhodes, Matthew G; Tauber, Sarah K

2011-01-01

Many studies have examined the accuracy of predictions of future memory performance solicited through judgments of learning (JOLs). Among the most robust findings in this literature is that delaying predictions serves to substantially increase the relative accuracy of JOLs compared with soliciting JOLs immediately after study, a finding termed the delayed JOL effect. The meta-analyses reported in the current study examined the predominant theoretical accounts as well as potential moderators of the delayed JOL effect. The first meta-analysis examined the relative accuracy of delayed compared with immediate JOLs across 4,554 participants (112 effect sizes) through gamma correlations between JOLs and memory accuracy. Those data showed that delaying JOLs leads to robust benefits to relative accuracy (g = 0.93). The second meta-analysis examined memory performance for delayed compared with immediate JOLs across 3,807 participants (98 effect sizes). Those data showed that delayed JOLs result in a modest but reliable benefit for memory performance relative to immediate JOLs (g = 0.08). Findings from these meta-analyses are well accommodated by theories suggesting that delayed JOL accuracy reflects access to more diagnostic information from long-term memory rather than being a by-product of a retrieval opportunity. However, these data also suggest that theories proposing that the delayed JOL effect results from a memorial benefit or the match between the cues available for JOLs and those available at test may also provide viable explanatory mechanisms necessary for a comprehensive account.

Bifurcation analysis of a delayed mathematical model for tumor growth

International Nuclear Information System (INIS)

Khajanchi, Subhas

2015-01-01

In this study, we present a modified mathematical model of tumor growth by introducing discrete time delay in interaction terms. The model describes the interaction between tumor cells, healthy tissue cells (host cells) and immune effector cells. The goal of this study is to obtain a better compatibility with reality for which we introduced the discrete time delay in the interaction between tumor cells and host cells. We investigate the local stability of the non-negative equilibria and the existence of Hopf-bifurcation by considering the discrete time delay as a bifurcation parameter. We estimate the length of delay to preserve the stability of bifurcating periodic solutions, which gives an idea about the mode of action for controlling oscillations in the tumor growth. Numerical simulations of the model confirm the analytical findings

Clonidine treatment delays postnatal motor development and blocks short-term memory in young mice.

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Cristina Calvino-Núñez

Full Text Available During the development of the nervous system, the perinatal period is particularly sensitive as neuronal connections are still forming in the brain of the neonate. Alpha2-adrenergic receptors are overexpressed temporarily in proliferative zones in the developing brain, reaching a peak during the first postnatal week of life. Both stimulation and blocking of these receptors during this period alter the development of neural circuits, affecting synaptic connectivity and neuronal responses. They even affect motor and cognitive skills later on in the adult. It's especially important to look for the early neurological consequences resulting from such modifications, because they may go unnoticed. The main objective of the present study has been to reaffirm the importance of the maturation of alpha-adrenergic system in mice, by carrying out a comprehensive examination of motor, behavioral and cognitive effects in neonates, during early postnatal development, following chronic administration of the drug Clonidine, an alpha2 adrenergic system agonist. Our study shows that mice treated postnatally with clonidine present a temporal delay in the appearance of developmental markers, a slow execution of vestibular reflexes during first postnatal week of life and a blockade of the short term memory in the novel object recognition task. Shortly after the treatment the startle response is hyperreactive.

Maintenance of ovulation inhibition with a new progestogen-only pill containing drospirenone after scheduled 24-h delays in pill intake

DEFF Research Database (Denmark)

Duijkers, Ingrid J M; Heger-Mahn, Doris; Drouin, Dominique

2016-01-01

by four placebo tablets. A previous study showed that this new drospirenone-only pill effectively inhibited ovulation. Clinical efficacy, however, can be affected by compliance, and delayed or forgotten pill intake often occurs in daily life. The aim of this study was to investigate if inhibition.......8%; only one subject in Group A fulfilled the ovulation criteria in Cycle 2. Follicular diameters in the regular-intake and the delayed-intake cycles were similar. CONCLUSION: Despite the 4-day hormone-free period and multiple intentional 24-h delays in tablet intake, ovulation inhibition was maintained...... inhibition by the new-generation oestrogen-free pill, containing 4-mg drospirenone for 24 days followed by a 4-day treatment-free period, was maintained despite four 24-h delays in tablet intake, so the impact of delayed intake on contraceptive reliability will be low....

Effects of delayed cord clamping on residual placental blood volume, hemoglobin and bilirubin levels in term infants: a randomized controlled trial.

Science.gov (United States)

Mercer, J S; Erickson-Owens, D A; Collins, J; Barcelos, M O; Parker, A B; Padbury, J F

2017-03-01

The objective of the study was to measure the effects of a 5-min delay (DCC) versus immediate cord clamping (ICC) on residual placental blood volume (RPBV) at birth, and hemoglobin and serum bilirubin at 24 to 48 h of age. In this prospective randomized controlled trial, 73 women with term (37 to 41 weeks) singleton fetuses were randomized to DCC (⩾5 min; n=37) or ICC (protocol violations. Cord milking was the proxy for DCC (n=11) when the provider could not wait. Infants randomized to DCC compared with ICC had significantly less RPBV (20.0 versus 30.8 ml kg -1 , Phemoglobin levels (19.4 versus 17.8 g dl -1 , P=0.002) at 24 to 48 h, with no difference in bilirubin levels. Term infants had early hematological advantage of DCC without increases in hyperbilirubinemia or symptomatic polycythemia.

Tobacco demand, delay discounting, and smoking topography among smokers with and without psychopathology.

Science.gov (United States)

Farris, Samantha G; Aston, Elizabeth R; Abrantes, Ana M; Zvolensky, Michael J

2017-10-01

Tobacco demand (i.e., relative value attributed to a given reinforcer) and delay discounting (i.e., relative preference for smaller immediate rewards over larger delayed rewards) are two behavioral economic processes that are linked to the progression of problematic substance use. These processes have not been studied among those with psychopathology, a vulnerable group of smokers. The current study examined differences in tobacco demand and delay discounting, and their association with smoking topography among smokers with (n=43) and without (n=64) past-year psychopathology. Adult daily smokers (n=107,M age =43.5; SD=9.7) participated in a study on "smoking behavior." Past-year psychological disorders were assessed via a clinician-administered diagnostic assessment. All subjects participated in an ad libitum smoking trial and then completed an assessment of delay discounting (Monetary Choice Questionnaire) and tobacco demand (Cigarette Purchase Task) approximately 45-60min post-smoking. Smokers with psychopathology, compared to those without, had significantly higher demand intensity and maximum expenditure on tobacco (O max ), but did not differ on other demand indices or delay discounting. Smokers with psychopathology had shorter average inter-puff intervals and shorter time to cigarette completion than smokers without psychopathology. Tobacco demand and delay discounting measures were significantly intercorrelated among smokers with psychopathology, but not those without. Both behavioral economic measures were associated with specific aspects of smoking topography in smokers with psychopathology. The association between tobacco demand and delay discounting is evident among smokers with psychopathology and both measures were most consistently related to smoking behavior. Copyright © 2017 Elsevier B.V. All rights reserved.

Global synchronization of general delayed complex networks with stochastic disturbances

International Nuclear Information System (INIS)

Tu Li-Lan

2011-01-01

In this paper, global synchronization of general delayed complex networks with stochastic disturbances, which is a zero-mean real scalar Wiener process, is investigated. The networks under consideration are continuous-time networks with time-varying delay. Based on the stochastic Lyapunov stability theory, Ito's differential rule and the linear matrix inequality (LMI) optimization technique, several delay-dependent synchronous criteria are established, which guarantee the asymptotical mean-square synchronization of drive networks and response networks with stochastic disturbances. The criteria are expressed in terms of LMI, which can be easily solved using the Matlab LMI Control Toolbox. Finally, two examples show the effectiveness and feasibility of the proposed synchronous conditions. (general)

Intent to Quit among Daily and Non-Daily College Student Smokers

Science.gov (United States)

Pinsker, E. A.; Berg, C. J.; Nehl, E. J.; Prokhorov, A. V.; Buchanan, T. S.; Ahluwalia, J. S.

2013-01-01

Given the high prevalence of young adult smoking, we examined (i) psychosocial factors and substance use among college students representing five smoking patterns and histories [non-smokers, quitters, native non-daily smokers (i.e. never daily smokers), converted non-daily smokers (i.e. former daily smokers) and daily smokers] and (ii) smoking…

Mitigating the Effects of Poverty and Crime: The Long-Term Effects of an Early Intervention Programme for Children Who Were Developmentally Delayed and Prenatally Exposed to Cocaine

Science.gov (United States)

Ullery, Mary Anne; Gonzalez, Antonio; Katz, Lynne

2016-01-01

This study explores the long-term impact on participation in the Linda Ray Intervention Program (LRIP) for children (n = 54) who were developmentally delayed and prenatally exposed to cocaine. By identifying a group of programme graduates from a high crime/high poverty neighbourhood in Miami-Dade County using ArcGIS 10.2 software, a…

Light deflection, lensing, and time delays from gravitational potentials and Fermat's principle in the presence of a cosmological constant

International Nuclear Information System (INIS)

Ishak, Mustapha

2008-01-01

The contributions of the cosmological constant to the deflection angle and the time delays are derived from the integration of the gravitational potential as well as from Fermat's principle. The findings are in agreement with recent results using exact solutions to Einstein's equations and reproduce precisely the new Λ term in the bending angle and the lens equation. The consequences on time-delay expressions are explored. While it is known that Λ contributes to the gravitational time delay, it is shown here that a new Λ term appears in the geometrical time delay as well. Although these newly derived terms are perhaps small for current observations, they do not cancel out as previously claimed. Moreover, as shown before, at galaxy cluster scale, the Λ contribution can be larger than the second-order term in the Einstein deflection angle for several cluster lens systems.

The impact of cognitive load on delayed recall.

Science.gov (United States)

Camos, Valérie; Portrat, Sophie

2015-08-01

Recent studies have suggested that long-term retention of items studied in a working memory span task depends on the refreshing of memory items-more specifically, on the number of refreshing opportunities. However, it was previously shown that refreshing depends on the cognitive load of the concurrent task introduced in the working memory span task. Thus, cognitive load should determine the long-term retention of items assessed in a delayed-recall test if such retention relies on refreshing. In two experiments, while the amount of refreshing opportunities remained constant, we varied the cognitive load of the concurrent task by either introducing tasks differing in their attentional demands or varying the pace of the concurrent task. To verify that this effect was related to refreshing and not to any maintenance mechanism, we also manipulated the availability of subvocal rehearsal. Replicating previous results, increasing cognitive load reduced immediate recall. This increase also had a detrimental effect on delayed recall. Conversely, the addition of concurrent articulation reduced immediate but not delayed recall. This study shows that both working and episodic memory traces depend on the cognitive load of the concurrent task, whereas the use of rehearsal affects only working memory performance. These findings add further evidence of the dissociation between subvocal rehearsal and attentional refreshing.

Medium-Term Stability of the Photon Beam Energy of An Elekta CompactTM Linear Accelerator Based on Daily Measurements of Beam Quality Factor

Directory of Open Access Journals (Sweden)

Mohammad Amin Mosleh-Shirazi

2016-04-01

Full Text Available Introduction In this study, we aimed to assess the medium-term energy stability of a 6MV Elekta CompactTM linear accelerator. To the best of our knowledge, this is the first published article to evaluate this linear accelerator in terms of energy stability. As well as investigating the stability of the linear accelerator energy over a period of several weeks, the results will be useful for estimation of the required tolerance values for the beam quality factor (BQF of the PTW QUICKCHECK weblineTM (QCW daily checking device. Materials and Methods Over a 13 week period of routine clinical service, 52 daily readings of BQF were taken and then analyzed for a 10×10 cm2 field. Results No decreasing or increasing trend in BQF was observed over the study period. The mean BQF value was estimated at 5.4483 with a standard deviation (SD of 0.0459 (0.8%. The mean value was only 0.1% different from the baseline value. Conclusion The results of this medium-term stability study of the Elekta Compact linear accelerator energy showed that 96.2% of the observed BQF values were within ±1.3% of the baseline value. This can be considered to be within the recommended tolerance for linear accelerator photon beam energy. If an approach of applying ±3 SD is taken, the tolerance level for BQF may be suggested to be set at ±2.5%. However, further research is required to establish a relationship between BQF value and the actual changes in beam energy and penetrative quality.

The functional neuroanatomy of multitasking: combining dual tasking with a short term memory task.

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Deprez, Sabine; Vandenbulcke, Mathieu; Peeters, Ron; Emsell, Louise; Amant, Frederic; Sunaert, Stefan

2013-09-01

Insight into the neural architecture of multitasking is crucial when investigating the pathophysiology of multitasking deficits in clinical populations. Presently, little is known about how the brain combines dual-tasking with a concurrent short-term memory task, despite the relevance of this mental operation in daily life and the frequency of complaints related to this process, in disease. In this study we aimed to examine how the brain responds when a memory task is added to dual-tasking. Thirty-three right-handed healthy volunteers (20 females, mean age 39.9 ± 5.8) were examined with functional brain imaging (fMRI). The paradigm consisted of two cross-modal single tasks (a visual and auditory temporal same-different task with short delay), a dual-task combining both single tasks simultaneously and a multi-task condition, combining the dual-task with an additional short-term memory task (temporal same-different visual task with long delay). Dual-tasking compared to both individual visual and auditory single tasks activated a predominantly right-sided fronto-parietal network and the cerebellum. When adding the additional short-term memory task, a larger and more bilateral frontoparietal network was recruited. We found enhanced activity during multitasking in components of the network that were already involved in dual-tasking, suggesting increased working memory demands, as well as recruitment of multitask-specific components including areas that are likely to be involved in online holding of visual stimuli in short-term memory such as occipito-temporal cortex. These results confirm concurrent neural processing of a visual short-term memory task during dual-tasking and provide evidence for an effective fMRI multitasking paradigm. © 2013 Elsevier Ltd. All rights reserved.

State estimation for discrete-time Markovian jumping neural networks with mixed mode-dependent delays

International Nuclear Information System (INIS)

Liu Yurong; Wang Zidong; Liu Xiaohui

2008-01-01

In this Letter, we investigate the state estimation problem for a new class of discrete-time neural networks with Markovian jumping parameters as well as mode-dependent mixed time-delays. The parameters of the discrete-time neural networks are subject to the switching from one mode to another at different times according to a Markov chain, and the mixed time-delays consist of both discrete and distributed delays that are dependent on the Markovian jumping mode. New techniques are developed to deal with the mixed time-delays in the discrete-time setting, and a novel Lyapunov-Krasovskii functional is put forward to reflect the mode-dependent time-delays. Sufficient conditions are established in terms of linear matrix inequalities (LMIs) that guarantee the existence of the state estimators. We show that both the existence conditions and the explicit expression of the desired estimator can be characterized in terms of the solution to an LMI. A numerical example is exploited to show the usefulness of the derived LMI-based conditions

Daily Readiness Huddles in Radiology-Improving Communication, Coordination, and Problem-Solving Reliability.

Science.gov (United States)

Donnelly, Lane F

Deploying an intentional daily management process is a key part to create high-reliability culture. Key components described in the literature for a successfully daily management process include leadership standard work, visual controls, daily accountability processes, and the discipline to stick to the process over the long term. We believe that the institution of a daily readiness huddle has helped us better coordinate and communicate as a department and improved our ability to deliver imaging services on a daily basis. The daily readiness huddle has enabled us to more rapidly identify issues and has brought accountability to seeing solutions to those issues brought to fruition. In addition, it has helped with team building, including between the radiologists and the nonphysician staff. Copyright © 2017 Elsevier Inc. All rights reserved.

Stability and bifurcation analysis of a generalized scalar delay differential equation.

Science.gov (United States)

Bhalekar, Sachin

2016-08-01

This paper deals with the stability and bifurcation analysis of a general form of equation D(α)x(t)=g(x(t),x(t-τ)) involving the derivative of order α ∈ (0, 1] and a constant delay τ ≥ 0. The stability of equilibrium points is presented in terms of the stability regions and critical surfaces. We provide a necessary condition to exist chaos in the system also. A wide range of delay differential equations involving a constant delay can be analyzed using the results proposed in this paper. The illustrative examples are provided to explain the theory.

Chimera states in complex networks: interplay of fractal topology and delay

Science.gov (United States)

Sawicki, Jakub; Omelchenko, Iryna; Zakharova, Anna; Schöll, Eckehard

2017-06-01

Chimera states are an example of intriguing partial synchronization patterns emerging in networks of identical oscillators. They consist of spatially coexisting domains of coherent (synchronized) and incoherent (desynchronized) dynamics. We analyze chimera states in networks of Van der Pol oscillators with hierarchical connectivities, and elaborate the role of time delay introduced in the coupling term. In the parameter plane of coupling strength and delay time we find tongue-like regions of existence of chimera states alternating with regions of existence of coherent travelling waves. We demonstrate that by varying the time delay one can deliberately stabilize desired spatio-temporal patterns in the system.

Discrete-Time Sliding-Mode Control of Uncertain Systems with Time-Varying Delays via Descriptor Approach

Directory of Open Access Journals (Sweden)

Maode Yan

2008-01-01

Full Text Available This paper considers the problem of robust discrete-time sliding-mode control (DT-SMC design for a class of uncertain linear systems with time-varying delays. By applying a descriptor model transformation and Moon's inequality for bounding cross terms, a delay-dependent sufficient condition for the existence of stable sliding surface is given in terms of linear matrix inequalities (LMIs. Based on this existence condition, the synthesized sliding mode controller can guarantee the sliding-mode reaching condition of the specified discrete-time sliding surface for all admissible uncertainties and time-varying delays. An illustrative example verifies the effectiveness of the proposed method.

Contralateral delay activity tracks object identity information in visual short term memory.

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Gao, Zaifeng; Xu, Xiaotian; Chen, Zhibo; Yin, Jun; Shen, Mowei; Shui, Rende

2011-08-11

Previous studies suggested that ERP component contralateral delay activity (CDA) tracks the number of objects containing identity information stored in visual short term memory (VSTM). Later MEG and fMRI studies implied that its neural source lays in superior IPS. However, since the memorized stimuli in previous studies were displayed in distinct spatial locations, hence possibly CDA tracks the object-location information instead. Moreover, a recent study implied the activation in superior IPS reflected the location load. The current research thus explored whether CDA tracks the object-location load or the object-identity load, and its neural sources. Participants were asked to remember one color, four identical colors or four distinct colors. The four-identical-color condition was the critical one because it contains the same amount of identity information as that of one color while the same amount of location information as that of four distinct colors. To ensure the participants indeed selected four colors in the four-identical-color condition, we also split the participants into two groups (low- vs. high-capacity), analyzed late positive component (LPC) in the prefrontal area, and collected participant's subjective-report. Our results revealed that most of the participants selected four identical colors. Moreover, regardless of capacity-group, there was no difference on CDA between one color and four identical colors yet both were lower than 4 distinct colors. Besides, the source of CDA was located in the superior parietal lobule, which is very close to the superior IPS. These results support the statement that CDA tracks the object identity information in VSTM. Copyright © 2011 Elsevier B.V. All rights reserved.

Daily activities of school-age children with cerebral palsy : development and learning

NARCIS (Netherlands)

Smits, H.W.

2011-01-01

In care and research, there is increasing interest in the daily lives of children with cerebral palsy (CP). So far, we know that CP can have a limiting impact on daily activities such as locomotion and self-care. What we, however, don’t know is how children with CP develop over time in terms of

Finite-Time Stability of Large-Scale Systems with Interval Time-Varying Delay in Interconnection

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T. La-inchua

2017-01-01

Full Text Available We investigate finite-time stability of a class of nonlinear large-scale systems with interval time-varying delays in interconnection. Time-delay functions are continuous but not necessarily differentiable. Based on Lyapunov stability theory and new integral bounding technique, finite-time stability of large-scale systems with interval time-varying delays in interconnection is derived. The finite-time stability criteria are delays-dependent and are given in terms of linear matrix inequalities which can be solved by various available algorithms. Numerical examples are given to illustrate effectiveness of the proposed method.

Numerical Integration of a Class of Singularly Perturbed Delay Differential Equations with Small Shift

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Gemechis File

2012-01-01

Full Text Available We have presented a numerical integration method to solve a class of singularly perturbed delay differential equations with small shift. First, we have replaced the second-order singularly perturbed delay differential equation by an asymptotically equivalent first-order delay differential equation. Then, Simpson’s rule and linear interpolation are employed to get the three-term recurrence relation which is solved easily by discrete invariant imbedding algorithm. The method is demonstrated by implementing it on several linear and nonlinear model examples by taking various values for the delay parameter and the perturbation parameter .

Fuzzy delay model based fault simulator for crosstalk delay fault test ...

Indian Academy of Sciences (India)

In this paper, a fuzzy delay model based crosstalk delay fault simulator is proposed. As design trends move towards nanometer technologies, more number of new parameters affects the delay of the component. Fuzzy delay models are ideal for modelling the uncertainty found in the design and manufacturing steps.

Local and global synchronization in general complex dynamical networks with delay coupling

International Nuclear Information System (INIS)

Lu Jianquan; Ho, Daniel W.C.

2008-01-01

Local and global synchronization of complex dynamical networks are studied in this paper. Some simple yet generic criteria ensuring delay-independent and delay-dependent synchronization are derived in terms of linear matrix inequalities (LMIs), which can be verified easily via interior-point algorithm. The assumption that the coupling configuration matrix is symmetric and irreducible, which is frequently used in other literatures, is removed. A network with a fixed delay and a special coupling scheme is given as an example to illustrate the theoretical results and the effectiveness of the proposed synchronization scheme

Scheduling Production Orders, Taking into Account Delays and Waste

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Dylewski Robert

2014-09-01

Full Text Available The article addresses the problem of determining the sequence of entering orders for production in a flexible manufacturing system implementing technological operations of cutting sheet metal. Adopting a specific ranking of production orders gives rise to the vector of delays and waste in the form of incompletely used sheets. A new method was postulated for determining the optimal sequence of orders in terms of two criteria: the total cost of delays and the amount of production waste. The examples illustrate the advantages of the proposed method compared with the popular heuristic principles.

Stability result of the Timoshenko system with delay and boundary feedback

KAUST Repository

Said-Houari, Belkacem; Soufyane, Abdelaziz

2012-01-01

Our interest in this paper is to analyse the asymptotic behaviour of a Timoshenko beam system together with two boundary controls, with delay terms in the first and second equation. Assuming the weights of the delay are small enough, we show that the system is well-posed using the semigroup theory. Furthermore, we introduce a Lyapunov functional that gives the exponential decay of the total energy. © 2012 The author.

Stability result of the Timoshenko system with delay and boundary feedback

KAUST Repository

Said-Houari, Belkacem

2012-01-06

Our interest in this paper is to analyse the asymptotic behaviour of a Timoshenko beam system together with two boundary controls, with delay terms in the first and second equation. Assuming the weights of the delay are small enough, we show that the system is well-posed using the semigroup theory. Furthermore, we introduce a Lyapunov functional that gives the exponential decay of the total energy. © 2012 The author.

Sharp conditions for global stability of Lotka-Volterra systems with distributed delays

Science.gov (United States)

Faria, Teresa

We give a criterion for the global attractivity of a positive equilibrium of n-dimensional non-autonomous Lotka-Volterra systems with distributed delays. For a class of autonomous Lotka-Volterra systems, we show that such a criterion is sharp, in the sense that it provides necessary and sufficient conditions for the global asymptotic stability independently of the choice of the delay functions. The global attractivity of positive equilibria is established by imposing a diagonal dominance of the instantaneous negative feedback terms, and relies on auxiliary results showing the boundedness of all positive solutions. The paper improves and generalizes known results in the literature, namely by considering systems with distributed delays rather than discrete delays.

The Strong Lensing Time Delay Challenge (2014)

Science.gov (United States)

Liao, Kai; Dobler, G.; Fassnacht, C. D.; Treu, T.; Marshall, P. J.; Rumbaugh, N.; Linder, E.; Hojjati, A.

2014-01-01

Time delays between multiple images in strong lensing systems are a powerful probe of cosmology. At the moment the application of this technique is limited by the number of lensed quasars with measured time delays. However, the number of such systems is expected to increase dramatically in the next few years. Hundred such systems are expected within this decade, while the Large Synoptic Survey Telescope (LSST) is expected to deliver of order 1000 time delays in the 2020 decade. In order to exploit this bounty of lenses we needed to make sure the time delay determination algorithms have sufficiently high precision and accuracy. As a first step to test current algorithms and identify potential areas for improvement we have started a "Time Delay Challenge" (TDC). An "evil" team has created realistic simulated light curves, to be analyzed blindly by "good" teams. The challenge is open to all interested parties. The initial challenge consists of two steps (TDC0 and TDC1). TDC0 consists of a small number of datasets to be used as a training template. The non-mandatory deadline is December 1 2013. The "good" teams that complete TDC0 will be given access to TDC1. TDC1 consists of thousands of lightcurves, a number sufficient to test precision and accuracy at the subpercent level, necessary for time-delay cosmography. The deadline for responding to TDC1 is July 1 2014. Submissions will be analyzed and compared in terms of predefined metrics to establish the goodness-of-fit, efficiency, precision and accuracy of current algorithms. This poster describes the challenge in detail and gives instructions for participation.

Is early cord clamping, delayed cord clamping or cord milking best?

Science.gov (United States)

Vatansever, Binay; Demirel, Gamze; Ciler Eren, Elif; Erel, Ozcan; Neselioglu, Salim; Karavar, Hande Nur; Gundogdu, Semra; Ulfer, Gozde; Bahadir, Selcen; Tastekin, Ayhan

2018-04-01

To compare the antioxidant status of three cord clamping procedures (early clamping, delayed clamping and milking) by analyzing the thiol-disulfide balance. This randomized controlled study enrolled 189 term infants who were divided into three groups according to the cord clamping procedure: early clamping, delayed clamping and milking. Blood samples were collected from the umbilical arteries immediately after clamping, and the thiol/disulfide homeostasis was analyzed. The native and total thiol levels were significantly (p total thiol ratio was significantly (p = .026) lower in the delayed cord clamping and milking groups compared with the early clamping groups. Early cord clamping causes the production of more disulfide bonds and lower thiol levels, indicating that oxidation reactions are increased in the early cord clamping procedure compared with the delayed cord clamping and milking procedures. The oxidant capacity is greater with early cord clamping than with delayed clamping or cord milking. Delayed cord clamping or milking are beneficial in neonatal care, and we suggest that they be performed routinely in all deliveries.

Intent to quit among daily and non-daily college student smokers

OpenAIRE

Pinsker, E. A.; Berg, C. J.; Nehl, E. J.; Prokhorov, A. V.; Buchanan, T. S.; Ahluwalia, J. S.

2012-01-01

Given the high prevalence of young adult smoking, we examined (i) psychosocial factors and substance use among college students representing five smoking patterns and histories [non-smokers, quitters, native non-daily smokers (i.e. never daily smokers), converted non-daily smokers (i.e. former daily smokers) and daily smokers] and (ii) smoking category as it relates to readiness to quit among current smokers. Of the 4438 students at six Southeast colleges who completed an online survey, 69.7%...

fMRI study of neural sensitization to hedonic stimuli in long-term, daily cannabis users.

Science.gov (United States)

Filbey, Francesca M; Dunlop, Joseph; Ketcherside, Ariel; Baine, Jessica; Rhinehardt, Tyler; Kuhn, Brittany; DeWitt, Sam; Alvi, Talha

2016-10-01

Although there is emergent evidence illustrating neural sensitivity to cannabis cues in cannabis users, the specificity of this effect to cannabis cues as opposed to a generalized hyper-sensitivity to hedonic stimuli has not yet been directly tested. Using fMRI, we presented 53 daily, long-term cannabis users and 68 non-using controls visual and tactile cues for cannabis, a natural reward, and, a sensory-perceptual control object to evaluate brain response to hedonic stimuli in cannabis users. The results showed an interaction between group and reward type such that the users had greater response during cannabis cues relative to natural reward cues (i.e., fruit) in the orbitofrontal cortex, striatum, anterior cingulate gyrus, and ventral tegmental area compared to non-users (cluster-threshold z = 2.3, P brain-behavior correlations between neural response to cannabis cues in fronto-striatal-temporal regions and subjective craving, marijuana-related problems, withdrawal symptoms, and levels of THC metabolites (cluster-threshold z = 2.3, P brain response to cannabis cues in long-term cannabis users that are above that of response to natural reward cues. These observations are concordant with incentive sensitization models suggesting sensitization of mesocorticolimbic regions and disruption of natural reward processes following drug use. Although the cross-sectional nature of this study does not provide information on causality, the positive correlations between neural response and indicators of cannabis use (i.e., THC levels) suggest that alterations in the reward system are, in part, related to cannabis use. Hum Brain Mapp 37:3431-3443, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

Does delayed pushing in the second stage of labor impact perinatal outcomes?

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Frey, Heather A; Tuuli, Methodius G; Cortez, Sarah; Odibo, Anthony O; Roehl, Kimberly A; Shanks, Anthony L; Macones, George A; Cahill, Alison G

2012-11-01

To estimate maternal, neonatal, and labor outcomes associated with delayed pushing. A retrospective cohort study of all consecutive women admitted to a single institution in labor at term who reached the second stage of labor. Pregnancies with multiple fetuses or major anomalies were excluded. Delayed pushing was defined as initiation of pushing ≥60 minutes after complete dilatation. Primary outcome was mode of delivery. Multivariable logistic regression was used to control for confounding. Of the 5290 women who met inclusion criteria, 471 (8.9%) employed delayed pushing, and 4819 (91.1%) pushed immediately. Delayed pushing was associated with increased rates of cesarean, operative vaginal delivery, maternal fever, and lower arterial cord pH. Duration of the second stage and length of time spent pushing were significantly longer with delayed pushing. Delayed pushing is associated with lower rates of spontaneous vaginal delivery and increased adverse maternal and neonatal outcomes. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Sensory processing and cognitive development of preterm and full term infants

Directory of Open Access Journals (Sweden)

Flávia Regina Ribeiro Cavalcanti Buffone

2016-10-01

Full Text Available Introduction: Current studies show the repercussion of sensory processing disorder in infant neurodevelopment. Little is known about the influence of these disorders in the infant’s cognitive development, however, it is known that they negatively interfere on daily life activities and remain during life course. Objective:To evaluate the relationship between sensory processing and cognitive development in infants and the association between prematurity and sensory processing in this population. Method: This is a cross-sectional study conducted in the Childcare Outpatient Department of the Hospital das Clínicas, Federal Universidade de Pernambuco, from December 2009 to August 2010. The sample consisted of 182 infants from 8 to 15 months, of which 54 (29.7% were born preterm with the prematurity age correction made to 40 weeks of gestational age. We used the Test of Sensory Functions in Infants (TSFI to evaluate the sensory processing and the Bayley Scales of Infant and Toddler Development III to assess cognitive development. Results: There was a significantly higher frequency of at risk and deficient sensory processing among preterm infants (37% when compared to term infants (21.9%. Cognitive delay was significantly higher (8.3% in infants with at risk and deficient sensory processing when compared to those with normal sensory processing (1.5%. Conclusion: Prematurity was a risk factor for sensory processing disorder, and infants diagnosed with this disorder showed cognitive delay more frequently. Prematurity alone was not associated with cognitive delay.

Delay and probability discounting among payday and title loan recipients.

Science.gov (United States)

Mahoney, Colin T; Lawyer, Steven R

2016-04-01

Payday and title loans are short-term loans associated with significant economic impact. Behavioral theories of impulsive choice may provide insight into behavioral processes that underlie the propensity to take out payday and title loans. Adults between the ages of 18 and 30 recruited from the community completed delay and probability discounting tasks for hypothetical money as well as measures of substance use. Patterns of discounting were characterized using a hyperbolic decay model and area under the curve. Participants who took out a payday and/or title loan in the past (n=41) exhibited more impulsive choice patterns on the delay discounting task than did those who did not (n=255). Substance use mediated this relationship between payday and title loan retention and delay discounting. These findings suggest potentially important relationships between payday/title loan borrowing, substance use, and delay discounting. Copyright © 2016 Elsevier B.V. All rights reserved.

Linear matrix inequality approach for synchronization control of fuzzy cellular neural networks with mixed time delays

International Nuclear Information System (INIS)

Balasubramaniam, P.; Kalpana, M.; Rakkiyappan, R.

2012-01-01

Fuzzy cellular neural networks (FCNNs) are special kinds of cellular neural networks (CNNs). Each cell in an FCNN contains fuzzy operating abilities. The entire network is governed by cellular computing laws. The design of FCNNs is based on fuzzy local rules. In this paper, a linear matrix inequality (LMI) approach for synchronization control of FCNNs with mixed delays is investigated. Mixed delays include discrete time-varying delays and unbounded distributed delays. A dynamic control scheme is proposed to achieve the synchronization between a drive network and a response network. By constructing the Lyapunov—Krasovskii functional which contains a triple-integral term and the free-weighting matrices method an improved delay-dependent stability criterion is derived in terms of LMIs. The controller can be easily obtained by solving the derived LMIs. A numerical example and its simulations are presented to illustrate the effectiveness of the proposed method. (interdisciplinary physics and related areas of science and technology)

Large daily stock variation is associated with cardiovascular mortality in two cities of Guangdong, China.

Science.gov (United States)

Lin, Hualiang; Zhang, Yonghui; Xu, Yanjun; Liu, Tao; Xiao, Jianpeng; Luo, Yuan; Xu, Xiaojun; He, Yanhui; Ma, Wenjun

2013-01-01

The current study aimed to examine the effects of daily change of the Shenzhen Stock Exchange Index on cardiovascular mortality in Guangzhou and Taishan, China. Daily mortality and stock performance data during 2006-2010 were collected to construct the time series for the two cities. A distributed lag non-linear model was utilized to examine the effect of daily stock index changes on cardiovascular mortality after controlling for potential confounding factors. We observed a delayed non-linear effect of the stock index change on cardiovascular mortality: both rising and declining of the stock index were associated with increased cardiovascular deaths. In Guangzhou, the 15-25 lag days cumulative relative risk of an 800 index drop was 2.08 (95% CI: 1.38-3.14), and 2.38 (95% CI: 1.31-4.31) for an 800 stock index increase on the cardiovascular mortality, respectively. In Taishan, the cumulative relative risk over 15-25 days lag was 1.65 (95% CI: 1.13-2.42) for an 800 index drop and 2.08 (95% CI: 1.26-3.42) for an 800 index rising, respectively. Large ups and downs in daily stock index might be important predictor of cardiovascular mortality.

Mean Square Exponential Stability of Stochastic Switched System with Interval Time-Varying Delays

Directory of Open Access Journals (Sweden)

Manlika Rajchakit

2012-01-01

Full Text Available This paper is concerned with mean square exponential stability of switched stochastic system with interval time-varying delays. The time delay is any continuous function belonging to a given interval, but not necessary to be differentiable. By constructing a suitable augmented Lyapunov-Krasovskii functional combined with Leibniz-Newton’s formula, a switching rule for the mean square exponential stability of switched stochastic system with interval time-varying delays and new delay-dependent sufficient conditions for the mean square exponential stability of the switched stochastic system are first established in terms of LMIs. Numerical example is given to show the effectiveness of the obtained result.

Differential Long-Term Effects of Haloperidol and Risperidone on the Acquisition and Performance of Tasks of Spatial Working and Short-Term Memory and Sustained Attention in Rats

Science.gov (United States)

Hutchings, Elizabeth J.; Waller, Jennifer L.

2013-01-01

A common feature of the neuropsychiatric disorders for which antipsychotic drugs are prescribed is cognitive dysfunction, yet the effects of long-term antipsychotic treatment on cognition are largely unknown. In the current study, we evaluated the effects of long-term oral treatment with the first-generation antipsychotic haloperidol (1.0 and 2.0 mg/kg daily) and the second-generation antipsychotic risperidone (1.25 and 2.5 mg/kg daily) on the acquisition and performance of two radial-arm maze (RAM) tasks and a five-choice serial reaction-time task (5C-SRTT) in rats during days 15–60 and 84–320 days of treatment, respectively. In the RAM, neither antipsychotic significantly affected the acquisition or performance of a spatial win shift or a delayed non–match-to-position task. Conversely, in the rats administered 5C-SRTT, haloperidol was associated with profound deficits in performance, and the subjects were not able to progress through all stages of task acquisition. Depending on the dose, risperidone was associated with a greater number of trials to meet specific performance criteria during task acquisition compared with vehicle-treated controls; however, most subjects were eventually able to achieve all levels of task acquisition. Both haloperidol and risperidone also increased the number of perseverative and time-out responses during certain stages of task acquisition, and the response and reward latencies were slightly higher than controls during several stages of the study. These results in rats suggest that while long-term treatment with haloperidol or risperidone may not significantly affect spatial working or short-term memory, both antipsychotics can (depending on dose) impair sustained attention, decrease psychomotor speed, increase compulsive-type behaviors, and impair cognitive flexibility. PMID:24042161

Differential long-term effects of haloperidol and risperidone on the acquisition and performance of tasks of spatial working and short-term memory and sustained attention in rats.

Science.gov (United States)

Hutchings, Elizabeth J; Waller, Jennifer L; Terry, Alvin V

2013-12-01

A common feature of the neuropsychiatric disorders for which antipsychotic drugs are prescribed is cognitive dysfunction, yet the effects of long-term antipsychotic treatment on cognition are largely unknown. In the current study, we evaluated the effects of long-term oral treatment with the first-generation antipsychotic haloperidol (1.0 and 2.0 mg/kg daily) and the second-generation antipsychotic risperidone (1.25 and 2.5 mg/kg daily) on the acquisition and performance of two radial-arm maze (RAM) tasks and a five-choice serial reaction-time task (5C-SRTT) in rats during days 15-60 and 84-320 days of treatment, respectively. In the RAM, neither antipsychotic significantly affected the acquisition or performance of a spatial win shift or a delayed non-match-to-position task. Conversely, in the rats administered 5C-SRTT, haloperidol was associated with profound deficits in performance, and the subjects were not able to progress through all stages of task acquisition. Depending on the dose, risperidone was associated with a greater number of trials to meet specific performance criteria during task acquisition compared with vehicle-treated controls; however, most subjects were eventually able to achieve all levels of task acquisition. Both haloperidol and risperidone also increased the number of perseverative and time-out responses during certain stages of task acquisition, and the response and reward latencies were slightly higher than controls during several stages of the study. These results in rats suggest that while long-term treatment with haloperidol or risperidone may not significantly affect spatial working or short-term memory, both antipsychotics can (depending on dose) impair sustained attention, decrease psychomotor speed, increase compulsive-type behaviors, and impair cognitive flexibility.

Representing delayed force feedback as a combination of current and delayed states.

Science.gov (United States)

Avraham, Guy; Mawase, Firas; Karniel, Amir; Shmuelof, Lior; Donchin, Opher; Mussa-Ivaldi, Ferdinando A; Nisky, Ilana

2017-10-01

To adapt to deterministic force perturbations that depend on the current state of the hand, internal representations are formed to capture the relationships between forces experienced and motion. However, information from multiple modalities travels at different rates, resulting in intermodal delays that require compensation for these internal representations to develop. To understand how these delays are represented by the brain, we presented participants with delayed velocity-dependent force fields, i.e., forces that depend on hand velocity either 70 or 100 ms beforehand. We probed the internal representation of these delayed forces by examining the forces the participants applied to cope with the perturbations. The findings showed that for both delayed forces, the best model of internal representation consisted of a delayed velocity and current position and velocity. We show that participants relied initially on the current state, but with adaptation, the contribution of the delayed representation to adaptation increased. After adaptation, when the participants were asked to make movements with a higher velocity for which they had not previously experienced with the delayed force field, they applied forces that were consistent with current position and velocity as well as delayed velocity representations. This suggests that the sensorimotor system represents delayed force feedback using current and delayed state information and that it uses this representation when generalizing to faster movements. NEW & NOTEWORTHY The brain compensates for forces in the body and the environment to control movements, but it is unclear how it does so given the inherent delays in information transmission and processing. We examined how participants cope with delayed forces that depend on their arm velocity 70 or 100 ms beforehand. After adaptation, participants applied opposing forces that revealed a partially correct representation of the perturbation using the current and the

Pinning synchronization of hybrid-coupled directed delayed dynamical network via intermittent control.

Science.gov (United States)

Cai, Shuiming; Zhou, Peipei; Liu, Zengrong

2014-09-01

This paper concerns the problem of exponential synchronization for a class of general delayed dynamical networks with hybrid coupling via pinning periodically intermittent control. Both the internal delay and coupling delay are taken into account in the network model. Meanwhile, the transmission delay and self-feedback delay are involved in the delayed coupling term. By establishing a new differential inequality, several simple and useful exponential synchronization criteria are derived analytically. It is shown that the controlled synchronization state can vary in comparison with the conventional synchronized solution, and the degree of the node and the inner delayed coupling matrix play important roles in the controlled synchronization state. By choosing different inner delayed coupling matrices and the degrees of the node, different controlled synchronization states can be obtained. Furthermore, the detail pinning schemes deciding what nodes should be chosen as pinned candidates and how many nodes are needed to be pinned for a fixed coupling strength are provided. The simple procedures illuminating how to design suitable intermittent controllers in real application are also given. Numerical simulations, including an undirected scale-free network and a directed small-world network, are finally presented to demonstrate the effectiveness of the theoretical results.

Expectancy of an open-book test decreases performance on a delayed closed-book test.

Science.gov (United States)

Agarwal, Pooja K; Roediger, Henry L

2011-11-01

Two experiments examined the influence of practice with, and the expectancy of, open-book tests (students viewed studied material while taking the test) versus closed-book tests (students completed the test without viewing the studied material) on delayed retention and transfer. Using GRE materials specifically designed for open-book testing, participants studied passages and then took initial open- or closed-book tests. Open-book testing led to better initial performance than closed-book testing, but on a delayed criterial (closed-book) test both types of testing produced similar retention after a two-day delay in Experiment 1. In Experiment 2 participants were informed in advance about the type of delayed criterial test to expect (open- or closed-book). Expecting an open-book test (relative to a closed-book test) decreased participants' time spent studying and their delayed test performance on closed-book comprehension and transfer tests, demonstrating that test expectancy can influence long-term learning. Expectancy of open-book tests may impair long-term retention and transfer compared to closed-book tests, despite superior initial performance on open-book tests and students' preference for open-book tests.

Forecasting the daily electricity consumption in the Moscow region using artificial neural networks

Science.gov (United States)

Ivanov, V. V.; Kryanev, A. V.; Osetrov, E. S.

2017-07-01

In [1] we demonstrated the possibility in principle for short-term forecasting of daily volumes of passenger traffic in the Moscow metro with the help of artificial neural networks. During training and predicting, a set of the factors that affect the daily passenger traffic in the subway is passed to the input of the neural network. One of these factors is the daily power consumption in the Moscow region. Therefore, to predict the volume of the passenger traffic in the subway, we must first to solve the problem of forecasting the daily energy consumption in the Moscow region.

H∞ state estimation of generalised neural networks with interval time-varying delays

Science.gov (United States)

Saravanakumar, R.; Syed Ali, M.; Cao, Jinde; Huang, He

2016-12-01

This paper focuses on studying the H∞ state estimation of generalised neural networks with interval time-varying delays. The integral terms in the time derivative of the Lyapunov-Krasovskii functional are handled by the Jensen's inequality, reciprocally convex combination approach and a new Wirtinger-based double integral inequality. A delay-dependent criterion is derived under which the estimation error system is globally asymptotically stable with H∞ performance. The proposed conditions are represented by linear matrix inequalities. Optimal H∞ norm bounds are obtained easily by solving convex problems in terms of linear matrix inequalities. The advantage of employing the proposed inequalities is illustrated by numerical examples.

Asymptotic Delay Analysis for Cross-Layer Delay-Based Routing in Ad Hoc Networks

Directory of Open Access Journals (Sweden)

Philippe Jacquet

2007-01-01

Full Text Available This paper addresses the problem of the evaluation of the delay distribution via analytical means in IEEE 802.11 wireless ad hoc networks. We show that the asymptotic delay distribution can be expressed as a power law. Based on the latter result, we present a cross-layer delay estimation protocol and we derive new delay-distribution-based routing algorithms, which are well adapted to the QoS requirements of real-time multimedia applications. In fact, multimedia services are not sensitive to average delays, but rather to the asymptotic delay distributions. Indeed, video streaming applications drop frames when they are received beyond a delay threshold, determined by the buffer size. Although delay-distribution-based routing is an NP-hard problem, we show that it can be solved in polynomial time when the delay threshold is large, because of the asymptotic power law distribution of the link delays.

Differential games in economic systems with delays

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Kim, A. V.; Kormyshev, V. M.; Novikov, M. Yu.; Nikonov, M. A.

2017-11-01

In the paper, we consider application of i-smooth analysis (A.V. Kim, 2015) to differential games with delays in economics (Dockner E.J., et all, 2000; R. Isaacs, 1999). The approach is developed in the framework of the theory of positional differential games (N.N. Krasovskii, A.I. Subbotin, 1988; A.V. Kryazhimskii, Yu.S. Osipov, 1973; Yu.S. Osipov, J. Appl. Math. Mech. Vol. 35, № 1, № 6, 1971) and is based on application of the extremal shift strategy. We consider basic notions and constructions of the approach-evasion problem for linear systems with delays. The necessary and sufficient conditions of solvability the approach-evasion problem in terms of special u-stable sets are presented in another paper.

Auditory short-term memory activation during score reading.

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Simoens, Veerle L; Tervaniemi, Mari

2013-01-01

Performing music on the basis of reading a score requires reading ahead of what is being played in order to anticipate the necessary actions to produce the notes. Score reading thus not only involves the decoding of a visual score and the comparison to the auditory feedback, but also short-term storage of the musical information due to the delay of the auditory feedback during reading ahead. This study investigates the mechanisms of encoding of musical information in short-term memory during such a complicated procedure. There were three parts in this study. First, professional musicians participated in an electroencephalographic (EEG) experiment to study the slow wave potentials during a time interval of short-term memory storage in a situation that requires cross-modal translation and short-term storage of visual material to be compared with delayed auditory material, as it is the case in music score reading. This delayed visual-to-auditory matching task was compared with delayed visual-visual and auditory-auditory matching tasks in terms of EEG topography and voltage amplitudes. Second, an additional behavioural experiment was performed to determine which type of distractor would be the most interfering with the score reading-like task. Third, the self-reported strategies of the participants were also analyzed. All three parts of this study point towards the same conclusion according to which during music score reading, the musician most likely first translates the visual score into an auditory cue, probably starting around 700 or 1300 ms, ready for storage and delayed comparison with the auditory feedback.

Dynamics of a delay differential equation model of hepatitis B virus infection.

Science.gov (United States)

Gourley, Stephen A; Kuang, Yang; Nagy, John D

2008-04-01

We formulate and systematically study the global dynamics of a simple model of hepatitis B virus in terms of delay differential equations. This model has two important and novel features compared to the well-known basic virus model in the literature. Specifically, it makes use of the more realistic standard incidence function and explicitly incorporates a time delay in virus production. As a result, the infection reproduction number is no longer dependent on the patient liver size (number of initial healthy liver cells). For this model, the existence and the component values of the endemic steady state are explicitly dependent on the time delay. In certain biologically interesting limiting scenarios, a globally attractive endemic equilibrium can exist regardless of the time delay length.

Asymptotic stability of discrete-time systems with time-varying delay subject to saturation nonlinearities

International Nuclear Information System (INIS)

Chen, S.-F.

2009-01-01

The asymptotic stability problem for discrete-time systems with time-varying delay subject to saturation nonlinearities is addressed in this paper. In terms of linear matrix inequalities (LMIs), a delay-dependent sufficient condition is derived to ensure the asymptotic stability. A numerical example is given to demonstrate the theoretical results.

Accelerated long-term forgetting in children with temporal lobe epilepsy.

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Gascoigne, Michael B; Smith, Mary Lou; Barton, Belinda; Webster, Richard; Gill, Deepak; Lah, Suncica

2014-07-01

Adults with temporal lobe epilepsy (TLE) have been found to have accelerated long-term forgetting, but this phenomenon has not yet been investigated in children. Although deficits in recall of materials after short (20- to 30-minute) delays have been shown to slowly emerge from childhood to adolescence in patients with TLE, it is unknown whether such a trend will also be found in recall of materials after long delays. This study examined the presence of accelerated long-term forgetting in children with TLE and how it relates to chronological age. Twenty-three children with TLE and 58 healthy controls of similar age, sex distribution and socioeconomic status completed a battery of neuropsychological tests, including standardised tests of story recall and design location, as well as two experimental tests requiring the learning of words and design locations to a criterion, both of which assessed recall after short (30-min) and long (7-day) delays. Word recall at the 7-day delay (relative to the 30-min recall) was significantly poorer in the TLE group, compared to the control group. The TLE group also exhibited worse 30-min recall performance on a standardised test of story recall. Individual patient analyses revealed dissociation between performance on the experimental and standardised verbal memory tests; children who were impaired on the experimental test (7-day delay) were not impaired on the standardised test (30-min delay). Compared to controls, patients with a left-hemisphere seizure focus recalled fewer words at short and long delays while patients with an abnormal hippocampus recalled fewer words at the long delay. No between-group differences were found with respect to the design location task. Age negatively correlated with the recall of words after short- and long-term delays within the TLE group, where older age was associated with worse memory. This association was not present in the control group. To our knowledge, this is the first study to show

Clinical trials with rasagiline: evidence for short-term and long-term effects.

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Siderowf, Andrew; Stern, Matthew

2006-05-23

Rasagiline (N-propargyl-1 (R)-aminoindan) is a selective, potent irreversible inhibitor of MAO-B that possesses neuroprotective and anti-apoptotic properties in a variety of in vitro and in vivo animal models relevant to Parkinson's disease (PD). Several randomized controlled clinical trials have demonstrated the safety and efficacy of rasagiline as monotherapy in PD and as adjunctive therapy for patients receiving levodopa. In addition, the 1-year randomized, delayed-start analysis of the TEMPO study suggests that rasagiline may slow the rate of progression of PD. The randomized delayed-start paradigm has potential to differentiate short-term symptomatic effects from long-term effects of anti-parkinsonian agents. In the future, long-term trials to examine the potential disease-modifying effects of rasagiline, which incorporate biological markers as well as clinical endpoints, may further elucidate the role of rasagiline in the treatment of both early and advanced PD.

Delayed fission

Energy Technology Data Exchange (ETDEWEB)

Hatsukawa, Yuichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1997-07-01

Delayed fission is a nuclear decay process that couples {beta} decay and fission. In the delayed fission process, a parent nucleus undergoes {beta} decay and thereby populates excited states in the daughter. If these states are of energies comparable to or greater than the fission barrier of the daughter, then fission may compete with other decay modes of the excited states in the daughter. In this paper, mechanism and some experiments of the delayed fission will be discussed. (author)

W-transform for exponential stability of second order delay differential equations without damping terms.

Science.gov (United States)

Domoshnitsky, Alexander; Maghakyan, Abraham; Berezansky, Leonid

2017-01-01

In this paper a method for studying stability of the equation [Formula: see text] not including explicitly the first derivative is proposed. We demonstrate that although the corresponding ordinary differential equation [Formula: see text] is not exponentially stable, the delay equation can be exponentially stable.

The majority of men with lifelong premature ejaculation prefer daily drug treatment: an observation study in a consecutive group of Dutch men

NARCIS (Netherlands)

Waldinger, Marcel D.; Zwinderman, Aeilko H.; Olivier, Berend; Schweitzer, Dave H.

2007-01-01

INTRODUCTION: Whether men with lifelong premature ejaculation (PE) prefer on-demand drug treatment to delay ejaculation time to daily drug treatment, has never been studied as a separate study question. AIM: To study how men with lifelong PE feel about the use of serotonergic antidepressants, and

Short-Term Anticoagulant Therapy and Thrombus Location Are Independent Risk Factors for Delayed Recanalization of Deep Vein Thrombosis.

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Zhang, Chuanlin; Fu, Qining; Zhao, Yu; Mu, Shaoyu; Liu, Liping

2016-01-21

Prompt recanalization of the vein containing the thrombus is an important goal during the initial treatment of DVT, and risk factors for delayed recanalization in patients with deep vein thrombosis (DVT) in the lower extremities need to be determined. A total of 174 patients with DVT in lower extremities were recruited from June 2014 to March 2015 at our hospital. Duplex ultrasound scanning was conducted for all patients at 1 and 6 months after baseline evaluation. We divided the patients into recanalization and non-recanalization groups and analyzed risk factors for delayed recanalization. The univariate analysis revealed that an oral anticoagulant time of less than 3 months and venous thrombus location were risk factors for delayed recanalization (P0.05). The multivariate analysis showed that patients with an anticoagulant time of less than 3 months had a lower incidence of recanalization than those with an anticoagulant time of more than 3 months (OR=2.358, Pvenous thrombus location are independent risk factors for delayed recanalization of DVT in the lower extremities.

An empirical model of daily highs and lows of West Texas Intermediate crude oil prices

International Nuclear Information System (INIS)

He, Angela W.W.; Wan, Alan T.K.; Kwok, Jerry T.K.

2010-01-01

There is a large collection of literature on energy price forecasting, but most studies typically use monthly average or close-to-close daily price data. In practice, the daily price range constructed from the daily high and low also contains useful information on price volatility and is used frequently in technical analysis. The interaction between the daily high and low and the associated daily range has been examined in several recent studies on stock price and exchange rate forecasts. The present paper adopts a similar approach to analyze the behaviour of the West Texas Intermediate (WTI) crude oil price over a ten-year period. We find that daily highs and lows of the WTI oil price are cointegrated, with the error correction term being closely approximated by the daily price range. Two forecasting models, one based on a vector error correction mechanism and the other based on a transfer function framework with the range taken as a driver variable, are presented for forecasting the daily highs and lows. The results show that both of these models offer significant advantages over the naive random walk and univariate ARIMA models in terms of out-of-sample forecast accuracy. A trading strategy that makes use of the daily high and low forecasts is further developed. It is found that this strategy generally yields very reasonable trading returns over an evaluation period of about two years. (author)

Delayed diagnosis of an isolated posterolateral corner injury: a case report.

Science.gov (United States)

Welsh, Patrick; DeGraauw, Christopher; Whitty, David

2016-12-01

Isolated injuries to the posterolateral corner of the knee are a rare and commonly missed injury associated with athletic trauma, motor vehicle accidents, and falls. Delayed or missed diagnoses can negatively impact patient prognosis, contributing to residual instability, chronic pain, and failure of surgical repair to other ligaments. A 44-year-old male CrossFit athlete presented with a history of two non-contact hyperextension injuries to his left knee while walking on ice. The only positive finding was the Dial Test at 30 degrees of knee flexion, indicative of an isolated posterolateral corner injury. After a delay in diagnosis, the patient underwent a reconstruction of the posterolateral corner and subsequent rehabilitation. Early recognition of this injury is important as this can affect the prognosis and activities of daily living of the patient. This case will discuss the clinical presentation, diagnostic procedures, and management of an isolated posterolateral corner injury and highlight the importance of early recognition and referrals from primary contact healthcare practitioners.

On global stability criterion for neural networks with discrete and distributed delays

International Nuclear Information System (INIS)

Park, Ju H.

2006-01-01

Based on the Lyapunov functional stability analysis for differential equations and the linear matrix inequality (LMI) optimization approach, a new delay-dependent criterion for neural networks with discrete and distributed delays is derived to guarantee global asymptotic stability. The criterion is expressed in terms of LMIs, which can be solved easily by various convex optimization algorithms. Some numerical examples are given to show the effectiveness of proposed method

Stability and bifurcation of a discrete BAM neural network model with delays

International Nuclear Information System (INIS)

Zheng Baodong; Zhang Yang; Zhang Chunrui

2008-01-01

A map modelling a discrete bidirectional associative memory neural network with delays is investigated. Its dynamics is studied in terms of local analysis and Hopf bifurcation analysis. By analyzing the associated characteristic equation, its linear stability is investigated and Hopf bifurcations are demonstrated. It is found that there exist Hopf bifurcations when the delay passes a sequence of critical values. Numerical simulation is performed to verify the analytical results

Fuzzy delay model based fault simulator for crosstalk delay fault test ...

Indian Academy of Sciences (India)

In this paper, a fuzzy delay model based crosstalk delay fault simulator is proposed. As design .... To find the quality of non-robust tests, a fuzzy delay ..... Dubois D and Prade H 1989 Processing Fuzzy temporal knowledge. IEEE Transactions ...

Delayed-Start Analyses in the Phase 3 Solanezumab EXPEDITION3 Study in Mild Alzheimer's Disease.

Science.gov (United States)

Liu-Seifert, H; Case, M G; Andersen, S W; Holdridge, K C; Aisen, P S; Kollack-Walker, S; Siemers, E

2018-01-01

A delayed-start design has been proposed to assess a potential disease-modifying effect in investigational drugs for Alzheimer's disease that target the underlying disease process. We extended this methodology to recently obtained data from the EXPEDITION3. EXPEDITION3 was a Phase 3, double-blind study with participants randomized to solanezumab (400 mg) or placebo every 4 weeks for 80 weeks, with an optional extension of active treatment. The delayed-start analysis was designed to determine if a statistically significant treatment difference established during the placebo-controlled period is maintained (at predefined level) during the delayed-start period, which would suggest the active drug has a disease-modifying effect. The delayed-start analysis was assessed across multiple efficacy measures, and includes data from baseline in the placebo-controlled period and up to 9 months in the delayed-start period. No significant difference was observed between the placebo and solanezumab treatment groups at the end of the placebo-controlled period for the Alzheimer's Disease Assessment Scale-Cognitive 14-item subscale. A significant treatment difference was observed at the end of the placebo-controlled period for the Alzheimer's Disease Cooperative Study-Activities of Daily Living instrumental items, an effect also seen at 6 months in the delayed-start period, and the noninferiority criterion was met. No other efficacy measures met these criteria. Delayed-start statistical methodology was used to understand the longitudinal outcomes in EXPEDITION3 and its extension. The small treatment differences observed at the end of the placebo-controlled phase prevented adequate assessment of any putative disease modifying effect.

Evaluation method for uncertainty of effective delayed neutron fraction βeff

International Nuclear Information System (INIS)

Zukeran, Atsushi

1999-01-01

Uncertainty of effective delayed neutron fraction β eff is evaluated in terms of three quantities; uncertainties of the basic delayed neutron constants, energy dependence of delayed neutron yield ν d m , and the uncertainties of the fission cross sections of fuel elements. The uncertainty of β eff due to the delayed neutron yield is expressed by a linearized formula assuming that the delayed neutron yield does not depend on the incident energy, and the energy dependence is supplemented by using the detailed energy dependence proposed by D'Angelo and Filip. The third quantity, uncertainties of fission cross section, is evaluated on the basis of the generalized perturbation theory in relation to reaction rate rations such as central spectral indexes or average reaction rate ratios. Resultant uncertainty of β eff is about 4 to 5%s, in which primary factor is the delayed neutron yield, and the secondary one is the fission cross section uncertainty, especially for 238 U. The energy dependence of ν d m systematically reduces the magnitude of β eff about 1.4% to 1.7%, depending on the model of the energy vs. ν d m correlation curve. (author)

Feeling old today? Daily health, stressors, and affect explain day-to-day variability in subjective age.

Science.gov (United States)

Kotter-Grühn, Dana; Neupert, Shevaun D; Stephan, Yannick

2015-01-01

Subjective age is an important correlate of health, well-being, and longevity. So far, little is known about short-term variability in subjective age and the circumstances under which individuals feel younger/older in daily life. This study examined whether (a) older adults' felt age fluctuates on a day-to-day basis, (b) daily changes in health, stressors, and affect explain fluctuations in felt age, and (c) the daily associations between felt age and health, stressors, or affect are time-ordered. Using an eight-day daily diary approach, N = 43 adults (60-96 years, M = 74.65, SD = 8.19) filled out daily questionnaires assessing subjective age, health, daily stressors, and affect. Data were analysed using multilevel modelling. Subjective age, health, daily stressors, affect. Intra-individual variability in felt age was not explained by time but by short-term variability in other variables. Specifically, on days when participants experienced more than average health problems, stress, or negative affect they felt older than on days with average health, stress, or negative affect. No time-ordered effects were found. Bad health, many stressors, and negative affective experiences constitute circumstances under which older adults feel older than they typically do. Thus, daily measures of subjective age could be markers of health and well-being.

Delayed power analysis

International Nuclear Information System (INIS)

Adamovich, L.A.; Azarov, V.V.

1999-01-01

Time dependent core power behavior in a nuclear reactor is described with well-known neutron kinetics equations. At the same time, two portions are distinguished in energy released from uranium nuclei fission; one released directly at fission and another delayed (residual) portion produced during radioactive decay of fission products. While prompt power is definitely described with kinetics equations, the delayed power presentation still remains outstanding. Since in operation the delayed power part is relatively small (about 6%) operation, it can be neglected for small reactivity disturbances assuming that entire power obeys neutron kinetics equations. In case of a high negative reactivity rapidly inserted in core (e.g. reactor scram initiation) the prompt and delayed components can be calculated separately with practically no impact on each other, employing kinetics equations for prompt power and known approximation formulas for delayed portion, named residual in this specific case. Under substantial disturbances the prompt component in the dynamic process becomes commensurable with delayed portion, thus making necessary to take into account their cross impact. A system of differential equations to describe time-dependent behavior of delayed power is presented. Specific NPP analysis shows a way to significantly simplify the task formulation. (author)

Associations of motor co-ordination and attention with motor-perceptual development in 3-year-old preterm and full-term children who needed neonatal intensive care.

Science.gov (United States)

Hemgren, E; Persson, K

2007-01-01

Children who have needed neonatal intensive care (NIC) are considered to be at risk for deficits such as developmental co-ordination disorder and attention-deficit/hyperactivity disorder. By assessing motor-perceptual development, motor co-ordination and attention already at 3 years of age, it might be possible to identify such deficits earlier than they are today. To investigate the motor-perceptual development in a group of 202 NIC children but had no major impairments, to describe associations of deficits in co-ordination and attention with motor-perceptual delays, and to estimate the prevalence of NIC children with combined deficits together with a motor-perceptual delay. Co-ordination and attention in children born very preterm (n = 57), moderately preterm (n = 75) and full-term (n = 70) were observed according to a model for Combined Assessment of Motor Performance and Behaviour while they were assessed using a developmental scale, Motor-Perceptual Development, 0-7 years, MPU. In two out of 14 MPU areas, a larger proportion of very preterm than of moderately preterm and full-term children had marked developmental delay. Overall, the proportion of NIC children having a motor-perceptual delay increased with increasing incoordination and especially increasing lack of attention. Twenty-one (11%) of the NIC children had different motor-perceptual delays combined with pronounced incoordination and pronounced lack of attention. Deficits in co-ordination and attention were associated with motor-perceptual delays in areas important for daily living and development of academic skills. Therefore, to find children at risk for developmental co-ordination disorder and attention-deficit/hyperactivity disorder, assessments of co-ordination and attention should be added to assessments of motor-perceptual development in 3-year-old NIC children.

Projective-anticipating, projective and projective-lag synchronization of chaotic systems with time-varying delays

International Nuclear Information System (INIS)

Feng Cunfang; Guan Wei; Wang Yinghai

2013-01-01

We investigate different types of projective (projective-anticipating, projective and projective-lag) synchronization in unidirectionally nonlinearly coupled time-delayed chaotic systems with variable time delays. Based on the Krasovskii–Lyapunov approach, we find both the existence and sufficient stability conditions, using a general class of time-delayed chaotic systems related to optical bistable or hybrid optical bistable devices. Our method has the advantage that it requires only one nonlinearly coupled term to achieve different types of projective synchronization in time-delayed chaotic systems with variable time delays. Compared with other existing works, our result provides an easy way to achieve projective-anticipating, projective and projective-lag synchronization. Numerical simulations of the Ikeda system are given to demonstrate the validity of the proposed method. (paper)

Maternal and Neonatal Outcomes With Early Compared With Delayed Pushing Among Nulliparous Women.

Science.gov (United States)

Yee, Lynn M; Sandoval, Grecio; Bailit, Jennifer; Reddy, Uma M; Wapner, Ronald J; Varner, Michael W; Caritis, Steve N; Prasad, Mona; Tita, Alan T N; Saade, George; Sorokin, Yoram; Rouse, Dwight J; Blackwell, Sean C; Tolosa, Jorge E

2016-11-01

To describe factors associated with delayed pushing and evaluate the relationship between delayed pushing and perinatal outcomes in nulliparous women with singleton term gestations. This was a secondary analysis of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Assessment of Perinatal Excellence cohort of 115,502 women and their neonates born in 25 U.S. hospitals from 2008 to 2011. Nulliparous women with singleton, cephalic, nonanomalous term births who achieved 10-cm cervical dilation were included. Women in whom pushing was delayed by 60 minutes or greater (delayed group) were compared with those who initiated pushing within 30 minutes (early group). Multivariable regression analyses were used to assess the independent association of delayed pushing with mode of delivery, length of the second stage, and other maternal and perinatal outcomes (significance defined as Ppushing was delayed in 18.4% (n=3,870). Women who were older, privately insured, or non-Hispanic white as well as those who had induction or augmentation of labor, diabetes, or epidural analgesia were more likely to have delayed pushing. Delayed pushing was more common when the second stage began during daytime hours or in hospitals with dedicated 24-hour obstetric anesthesia, although differences were small. After adjusting for differences in baseline and labor characteristics including center, women in the delayed group had longer mean durations of the second stage (191 compared with 84 minutes, Ppushing (86 compared with 76 minutes, Ppushing was associated with greater rates of cesarean delivery (11.2% compared with 5.1%; adjusted odds ratio [OR] 1.86, 95% confidence interval [CI] 1.63-2.12), operative vaginal delivery (adjusted OR 1.26, 95% CI 1.14-1.40), postpartum hemorrhage (adjusted OR 1.43, 95% CI 1.05-1.95), and blood transfusion (adjusted OR 1.51, 95% CI 1.04-2.17). Delayed pushing was not associated with increased odds of adverse neonatal outcomes

The PANGAEA study design - a prospective, multicenter, non-interventional, long-term study on fingolimod for the treatment of multiple sclerosis in daily practice.

Science.gov (United States)

Ziemssen, Tjalf; Kern, Raimar; Cornelissen, Christian

2015-06-18

Fingolimod (Gilenya) is an oral medication for patients with highly active relapsing-remitting Multiple Sclerosis (RRMS). Clinical trials and post-marketing experience on more than 114,000 patients have established a detailed safety profile. Total patient exposure now exceeds 195,000 patient-years as stated in the last financial report (Dec 2014) of the Novartis Pharma AG, Basel, Switzerland. However, less is known about the safety of long-term fingolimod use in daily practice. Here, we describe the study design of PANGAEA (Post-Authorization Non-interventional German sAfety of GilEnyA in RRMS patients), a prospective, multicenter, non-interventional, long-term study to collect safety, efficacy, and pharmacoeconomic data on RRMS patients treated with fingolimod (0.5 mg/daily) under real-world conditions in Germany. PANGAEA is striving to assess a real-world safety and efficacy profile of fingolimod, based on data from 4,000 RRMS patients, obtained during a 60-month observational phase. A pharmacoeconomic sub-study of 800 RRMS patients further collects patient-reported outcome measures of disability, quality of life, compliance, treatment satisfaction, and usage of resources during a 24-month observational phase. Descriptive statistical analyses of the safety set as well as of stratified subgroups such as patients with concomitant diabetes mellitus and pretreated patients (e.g., natalizumab) will be conducted. PANGAEA seeks to confirm the current safety profile of fingolimod obtained in phase I-III clinical trials. The study design presented here will additionally provide guidance on the therapeutic use of fingolimod in clinical practice and possibly assists physicians in making evidence-based decisions.

8-group relative delayed neutron yields for monoenergetic neutron induced fission of 239Pu

International Nuclear Information System (INIS)

Piksaikin, V.M.; Kazakov, L.E.; Isaev, S.G.; Korolev, G.G.; Roshchenko, V.A.; Tertychnyj, R.G

2002-01-01

The energy dependence of the relative yield of delayed neutrons in an 8-group model representation was obtained for monoenergetic neutron induced fission of 239 Pu. A comparison of this data with the available experimental data by other authors was made in terms of the mean half-life of the delayed neutron precursors. (author)

Extinction and permanence in delayed stage-structure predator-prey system with impulsive effects

International Nuclear Information System (INIS)

Pang Guoping; Wang Fengyan; Chen Lansun

2009-01-01

Based on the classical stage-structured model and Lotka-Volterra predator-prey model, an impulsive delayed differential equation to model the process of periodically releasing natural enemies at fixed times for pest control is proposed and investigated. We show that the conditions for global attractivity of the 'pest-extinction' ('prey-eradication') periodic solution and permanence of the population of the model depend on time delay. We also show that constant maturation time delay and impulsive releasing for the predator can bring great effects on the dynamics of system by numerical analysis. As a result, the pest maturation time delay is considered to establish a procedure to maintain the pests at an acceptably low level in the long term. In this paper, the main feature is that we introduce time delay and pulse into the predator-prey (natural enemy-pest) model with age structure, exhibit a new modelling method which is applied to investigate impulsive delay differential equations, and give some reasonable suggestions for pest management.

Effects of daily living occupational therapy and resistance exercise on the activities of daily living and muscular fitness in Guillain-Barré syndrome: a case study.

Science.gov (United States)

Ko, Kwang-Jun; Ha, Gi-Chul; Kang, Seol-Jung

2017-05-01

[Purpose] The study aimed to investigate the effects of daily living occupational therapy and resistance exercise on the performance of activities of daily living and muscular fitness in a patient with Guillain-Barré syndrome. [Subject and Methods] A 35-year-old man was diagnosed with Guillain-Barré syndrome. He was hospitalized at A Hospital for 3 years, and was discharged from the hospital after he became able to execute daily life activities. After discharge, he performed daily occupational therapy and resistance exercise twice a week for 70 minutes per session for 12 weeks. Performance in the activities of daily living was assessed using the modified Barthel index, and muscular fitness was measured in terms of isokinetic muscular function using the Biodes system. [Results] The subject's Barthel index score improved from 54 points before the intervention to 62 points after 4 weeks, 69 points after 8 weeks, and 79 points after 12 weeks. In addition, his shoulder flexion and extension, knee flexion and extension, and lumbar flexion and extension were improved. [Conclusion] The present study suggests that daily living occupational therapy and resistance exercise are effective in improving the activities of daily living and muscular fitness in a patient recovering from Guillain-Barré syndrome.

Estimation of the mechanical loading of the shoulder joint in daily conditions

NARCIS (Netherlands)

De Vries, W.H.K.

2015-01-01

The goal of this thesis is to assemble a method to estimate shoulder joint reaction forces, in daily conditions, based on long term collection of ambulatory measurable variables, to obtain the desired long term mechanical load profile of the shoulder. Chapter 2 examines, and discusses one of the

Delayed Growth Suppression and Radioresistance Induced by Long-Term Continuous Gamma Irradiation.

Science.gov (United States)

Nakajima, Hiroo; Furukawa, Chiharu; Chang, Young-Chae; Ogata, Hiromitsu; Magae, Junji

2017-08-01

Biological response to ionizing radiation depends not only on the type of radiation and dose, but also on the duration and dose rate of treatment. For a given radiation dose, the biological response may differ based on duration and dose rate. We studied the properties of two human cell lines, M059K glioma and U2OS osteosarcoma, continuously exposed to γ rays for long time periods of more than five months. Growth inhibition in both cell lines was dependent on total dose when exposed to acute radiation over several minutes, whereas prolonged growth inhibition was dependent on dose rate after continuous irradiation over several months. The minimum dose rate for growth inhibition was 53.6 mGy/h. Cell cycle analysis showed G 1 phase accumulation in cell populations continuously exposed to γ rays, and G 2 phase accumulation in cells acutely exposed to high-dose-rate γ rays. Cells continuously exposed to γ rays continued to exhibit delayed growth suppression even after one month in an environment of background radiation, and maintained a high-level expression of c-Jun and its phosphorylation forms, as well as resistance to apoptosis induced by staurosporine and chemotherapeutic agents. These delayed effects were not observed in cells acutely exposed to 5 Gy of radiation. These results suggest that optimization of the irradiation schedule is crucial for risk estimation, protection and therapeutic utilization of ionizing radiation.

Patient Delay, Diagnosis Delay and Treatment Delay for Breast Cancer: Comparison of the Pattern between Patients in Public and Private Health Sectors

Directory of Open Access Journals (Sweden)

Iraj Harirchi

2015-05-01

Full Text Available Background: The purpose of this study was to compare patient delay, diagnosis delay and treatment delay in breast cancer patients of selected public and private health centers in Tehran, Iran.Methods: In this cross-sectional study, female patients with newly diagnosed breast cancer in a public medical complex and a private breast clinic within one year were included. Patient delay was considered positive, if the interval between the detection of the first symptom by the patient and the first visit to a health care provider took longer than one month. Delay in diagnosis was defined as the period of more than one week between the first medical visit for the symptoms and the diagnosis of breast cancer. Following the confirmed diagnosis of breast malignancy, if the medical treatment was initiated later than one week, treatment delay had occurred. The potential reasons for patient, diagnosis and treatment delay according to the patients’ reports were also recorded.Results: Overall, 385 patients were included of whom 52.7% were recruited from the public hospitals and 47.3% from a private clinic. The prevalence of patient delay, diagnosis delay and treatment delay were 31.7%, 17.9% and 28.3%, respectively. Patient delay was significantly more common among patients with lower socio-economic status and those recruited from the public hospitals. All the patients with diagnosis delay were in the group recruited from the public hospitals.Conclusions: Gaps between women of different socio-economic levels of the society need to be addressed in order to decrease patient, diagnosis and treatment delay.

Speech and Language Delay

Science.gov (United States)

... OTC Relief for Diarrhea Home Diseases and Conditions Speech and Language Delay Condition Speech and Language Delay Share Print Table of Contents1. ... Treatment6. Everyday Life7. Questions8. Resources What is a speech and language delay? A speech and language delay ...

Daily Physical Activity and Cognitive Function Variability in Older Adults.

Science.gov (United States)

Phillips, Christine B; Edwards, Jerri D; Andel, Ross; Kilpatrick, Marcus

2016-04-01

Physical activity (PA) is believed to preserve cognitive function in older adulthood, though little is known about these relationships within the context of daily life. The present microlongitudinal pilot study explored within- and between-person relationships between daily PA and cognitive function and also examined within-person effect sizes in a sample of community-dwelling older adults. Fifty-one healthy participants (mean age = 70.1 years) wore an accelerometer and completed a cognitive assessment battery for five days. There were no significant associations between cognitive task performance and participants' daily or average PA over the study period. Effect size estimates indicated that PA explained 0-24% of within-person variability in cognitive function, depending on cognitive task and PA dose. Results indicate that PA may have near-term cognitive effects and should be explored as a possible strategy to enhance older adults' ability to perform cognitively complex activities within the context of daily living.

Impact of leakage delay on bifurcation in high-order fractional BAM neural networks.

Science.gov (United States)

Huang, Chengdai; Cao, Jinde

2018-02-01

The effects of leakage delay on the dynamics of neural networks with integer-order have lately been received considerable attention. It has been confirmed that fractional neural networks more appropriately uncover the dynamical properties of neural networks, but the results of fractional neural networks with leakage delay are relatively few. This paper primarily concentrates on the issue of bifurcation for high-order fractional bidirectional associative memory(BAM) neural networks involving leakage delay. The first attempt is made to tackle the stability and bifurcation of high-order fractional BAM neural networks with time delay in leakage terms in this paper. The conditions for the appearance of bifurcation for the proposed systems with leakage delay are firstly established by adopting time delay as a bifurcation parameter. Then, the bifurcation criteria of such system without leakage delay are successfully acquired. Comparative analysis wondrously detects that the stability performance of the proposed high-order fractional neural networks is critically weakened by leakage delay, they cannot be overlooked. Numerical examples are ultimately exhibited to attest the efficiency of the theoretical results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Instantaneous-to-daily GPP upscaling schemes based on a coupled photosynthesis-stomatal conductance model: correcting the overestimation of GPP by directly using daily average meteorological inputs.

Science.gov (United States)

Wang, Fumin; Gonsamo, Alemu; Chen, Jing M; Black, T Andrew; Zhou, Bin

2014-11-01

Daily canopy photosynthesis is usually temporally upscaled from instantaneous (i.e., seconds) photosynthesis rate. The nonlinear response of photosynthesis to meteorological variables makes the temporal scaling a significant challenge. In this study, two temporal upscaling schemes of daily photosynthesis, the integrated daily model (IDM) and the segmented daily model (SDM), are presented by considering the diurnal variations of meteorological variables based on a coupled photosynthesis-stomatal conductance model. The two models, as well as a simple average daily model (SADM) with daily average meteorological inputs, were validated using the tower-derived gross primary production (GPP) to assess their abilities in simulating daily photosynthesis. The results showed IDM closely followed the seasonal trend of the tower-derived GPP with an average RMSE of 1.63 g C m(-2) day(-1), and an average Nash-Sutcliffe model efficiency coefficient (E) of 0.87. SDM performed similarly to IDM in GPP simulation but decreased the computation time by >66%. SADM overestimated daily GPP by about 15% during the growing season compared to IDM. Both IDM and SDM greatly decreased the overestimation by SADM, and improved the simulation of daily GPP by reducing the RMSE by 34 and 30%, respectively. The results indicated that IDM and SDM are useful temporal upscaling approaches, and both are superior to SADM in daily GPP simulation because they take into account the diurnally varying responses of photosynthesis to meteorological variables. SDM is computationally more efficient, and therefore more suitable for long-term and large-scale GPP simulations.

Exponential stability of uncertain stochastic neural networks with mixed time-delays

International Nuclear Information System (INIS)

Wang Zidong; Lauria, Stanislao; Fang Jian'an; Liu Xiaohui

2007-01-01

This paper is concerned with the global exponential stability analysis problem for a class of stochastic neural networks with mixed time-delays and parameter uncertainties. The mixed delays comprise discrete and distributed time-delays, the parameter uncertainties are norm-bounded, and the neural networks are subjected to stochastic disturbances described in terms of a Brownian motion. The purpose of the stability analysis problem is to derive easy-to-test criteria under which the delayed stochastic neural network is globally, robustly, exponentially stable in the mean square for all admissible parameter uncertainties. By resorting to the Lyapunov-Krasovskii stability theory and the stochastic analysis tools, sufficient stability conditions are established by using an efficient linear matrix inequality (LMI) approach. The proposed criteria can be checked readily by using recently developed numerical packages, where no tuning of parameters is required. An example is provided to demonstrate the usefulness of the proposed criteria

Delayed rule following.

Science.gov (United States)

Schmitt, D R

2001-01-01

Although the elements of a fully stated rule (discriminative stimulus [S(D)], some behavior, and a consequence) can occur nearly contemporaneously with the statement of the rule, there is often a delay between the rule statement and the S(D). The effects of this delay on rule following have not been studied in behavior analysis, but they have been investigated in rule-like settings in the areas of prospective memory (remembering to do something in the future) and goal pursuit. Discriminative events for some behavior can be event based (a specific setting stimulus) or time based. The latter are more demanding with respect to intention following and show age-related deficits. Studies suggest that the specificity with which the components of a rule (termed intention) are stated has a substantial effect on intention following, with more detailed specifications increasing following. Reminders of an intention, too, are most effective when they refer specifically to both the behavior and its occasion. Covert review and written notes are two effective strategies for remembering everyday intentions, but people who use notes appear not to be able to switch quickly to covert review. By focusing on aspects of the setting and rule structure, research on prospective memory and goal pursuit expands the agenda for a more complete explanation of rule effects.

Improvement in Activities of Daily Living among Danish Centenarians?

DEFF Research Database (Denmark)

Rasmussen, Signe Høi; Thinggaard, Mikael; Højgaard, Majken Boris

2018-01-01

at investigating if the later born cohort had better functioning in terms of activities of daily living (ADL). Methods: Identification, methodology and assessment instruments were identical in the 1895-West and 1915-West Birth Cohort Studies: All persons living in the western part of Denmark and turning 100 years...

Synchronization of delayed systems in the presence of delay time modulation

International Nuclear Information System (INIS)

Kye, Won-Ho; Choi, Muhan; Kim, Myung-Woon; Lee, Soo-Young; Rim, Sunghwan; Kim, Chil-Min; Park, Young-Jai

2004-01-01

We investigate synchronization in the presence of delay time modulation for application to communication. We have observed that the robust synchronization is established by a common delay signal and its threshold is presented using Lyapunov exponents analysis. The influence of the delay time modulation in chaotic oscillators is also discussed

Cooperative relay-based multicasting for energy and delay minimization

KAUST Repository

Atat, Rachad

2012-08-01

Relay-based multicasting for the purpose of cooperative content distribution is studied. Optimized relay selection is performed with the objective of minimizing the energy consumption or the content distribution delay within a cluster of cooperating mobiles. Two schemes are investigated. The first consists of the BS sending the data only to the relay, and the second scheme considers the scenario of threshold-based multicasting by the BS, where a relay is selected to transmit the data to the mobiles that were not able to receive the multicast data. Both schemes show significant superiority compared to the non-cooperative scenarios, in terms of energy consumption and delay reduction. © 2012 IEEE.

Daily transactional and transformational leadership and daily employee engament

NARCIS (Netherlands)

Breevaart, K.; Bakker, A.B.; Hetland, Jorn; Demerouti, E.; Olsen, O.K.; Espevik, R.

2014-01-01

This diary study adds to the leadership literature by examining the daily influence of transformational leadership, contingent reward, and active management-by-exception (MBE active) on followers' daily work engagement. We compare the unique contribution of these leadership behaviours and focus on

Thalidomide for control delayed vomiting in cancer patients receiving chemotherapy

International Nuclear Information System (INIS)

Han, Z.; Sun, X.; Du, X.

2016-01-01

To explore the efficacy and safety of thalidomide for the treatment of delayed vomiting, induced by chemotherapy in cancer patients. Study Design: Randomized, double-blind controlled study. Place and Duration of Study: The Oncology Department of Affiliated Hospital of Xuzhou Medical University, Jiangsu Xuzhou, China, from January 2012 to January 2014. Methodology: A total of 78 cancer patients, who had delayed vomiting observed from 24 hours to 1 week after chemotherapy, were included in the study. Patients were divided in a treatment group (40 patients, 51.28%) and a control group (38 patients, 48.71%). The treatment group received thalidomide at an oral dose of 100 mg per night; 50 mg was added daily up to a dose of 200 mg per night, if the curative effect was suboptimal and the medicine was tolerated. Both the treatment and the control groups received a drip of 10 mg azasetron 30 minutes before chemotherapy. The control group only proportions of antiemetic effects and adverse reactions were compared using the ?2 test. Antiemetic effects and adverse reactions were assessed from Odds Ratios (OR) with 95% Confidence Intervals(95% CI). Results: The effective control rate of delayed vomiting in the treatment group was significantly higher than that in the control group (?2=5.174, p=0.023). No significant difference was found between the two groups in other adverse effects of chemotherapy. Karnofsky scores or the overall self-evaluation of the patients (p>0.05). Conclusion: Thalidomide can effectively control the delayed vomiting of cancer patients receiving chemotherapy and the adverse reactions of the agent can be tolerated.

Creating a Long-Term Diabetic Rabbit Model

Directory of Open Access Journals (Sweden)

Jianpu Wang

2010-01-01

Full Text Available This study was to create a long-term rabbit model of diabetes mellitus for medical studies of up to one year or longer and to evaluate the effects of chronic hyperglycemia on damage of major organs. A single dose of alloxan monohydrate (100 mg/kg was given intravenously to 20 young New Zealand White rabbits. Another 12 age-matched normal rabbits were used as controls. Hyperglycemia developed within 48 hours after treatment with alloxan. Insulin was given daily after diabetes developed. All animals gained some body weight, but the gain was much less than the age-matched nondiabetic rabbits. Hyperlipidemia, higher blood urea nitrogen and creatinine were found in the diabetic animals. Histologically, the pancreas showed marked beta cell damage. The kidneys showed significantly thickened afferent glomerular arterioles with narrowed lumens along with glomerular atrophy. Lipid accumulation in the cytoplasm of hepatocytes appeared as vacuoles. Full-thickness skin wound healing was delayed. In summary, with careful management, alloxan-induced diabetic rabbits can be maintained for one year or longer in reasonably good health for diabetic studies.

Wigner-Smith delay times and the non-Hermitian Hamiltonian for the HOCl molecule

International Nuclear Information System (INIS)

Barr, A.M.; Reichl, L.E.

2013-01-01

We construct the scattering matrix for a two-dimensional model of a Cl atom scattering from an OH dimer. We show that the scattering matrix can be written in terms of a non-Hermitian Hamiltonian whose complex energy eigenvalues can be used to compute Wigner-Smith delay times for the Cl-OH scattering process. We compute the delay times for a range of energies, and show that the scattering states with the longest delay times are strongly influenced by unstable periodic orbits in the classical dynamics. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Mice deficient for striatal Vesicular Acetylcholine Transporter (VAChT) display impaired short-term but normal long-term object recognition memory.

Science.gov (United States)

Palmer, Daniel; Creighton, Samantha; Prado, Vania F; Prado, Marco A M; Choleris, Elena; Winters, Boyer D

2016-09-15

Substantial evidence implicates Acetylcholine (ACh) in the acquisition of object memories. While most research has focused on the role of the cholinergic basal forebrain and its cortical targets, there are additional cholinergic networks that may contribute to object recognition. The striatum contains an independent cholinergic network comprised of interneurons. In the current study, we investigated the role of this cholinergic signalling in object recognition using mice deficient for Vesicular Acetylcholine Transporter (VAChT) within interneurons of the striatum. We tested whether these striatal VAChT(D2-Cre-flox/flox) mice would display normal short-term (5 or 15min retention delay) and long-term (3h retention delay) object recognition memory. In a home cage object recognition task, male and female VAChT(D2-Cre-flox/flox) mice were impaired selectively with a 15min retention delay. When tested on an object location task, VAChT(D2-Cre-flox/flox) mice displayed intact spatial memory. Finally, when object recognition was tested in a Y-shaped apparatus, designed to minimize the influence of spatial and contextual cues, only females displayed impaired recognition with a 5min retention delay, but when males were challenged with a 15min retention delay, they were also impaired; neither males nor females were impaired with the 3h delay. The pattern of results suggests that striatal cholinergic transmission plays a role in the short-term memory for object features, but not spatial location. Copyright © 2016 Elsevier B.V. All rights reserved.

Chaos synchronization in time-delayed systems with parameter mismatches and variable delay times

International Nuclear Information System (INIS)

Shahverdiev, E.M.; Nuriev, R.A.; Hashimov, R.H.; Shore, K.A.

2004-06-01

We investigate synchronization between two undirectionally linearly coupled chaotic nonidentical time-delayed systems and show that parameter mismatches are of crucial importance to achieve synchronization. We establish that independent of the relation between the delay time in the coupled systems and the coupling delay time, only retarded synchronization with the coupling delay time is obtained. We show that with parameter mismatch or without it neither complete nor anticipating synchronization occurs. We derive existence and stability conditions for the retarded synchronization manifold. We demonstrate our approach using examples of the Ikeda and Mackey Glass models. Also for the first time we investigate chaos synchronization in time-delayed systems with variable delay time and find both existence and sufficient stability conditions for the retarded synchronization manifold with the coupling-delay lag time. (author)

Daily mini quizzes as means for improving student performance in anatomy course.

Science.gov (United States)

Poljicanin, Ana; Carić, Ana; Vilović, Katarina; Kosta, Vana; Marinović Guić, Maja; Aljinović, Jure; Grković, Ivica

2009-02-01

To evaluate daily-written 10-question quizzes in a medical anatomy course as a way to integrate assessment into the course and to evaluate their effect on the course success. Students answering correctly 8/10 or more questions were awarded 0.5 points per quiz. There were 34 quizzes with a maximum point score 17. Measurable outcomes of academic progress in anatomy course (pass rates on 4 examination terms, total pass rate, and average marks) were calculated, and 2007/08 academic year was compared with the previous academic year in which daily written quizzes were not a part of the course. The relationship between cumulative points on daily quizzes and 3 components of the final examination (written, practical, and oral) for 2007/08 academic year was assessed by non-parametric correlation testing. Individual scores on quizzes ranged from 1.5 to 13.5 points. There was a positive correlation between scores on quizzes and grades on 3 components of the final examination: written (Spearman rho=0.784, Pstudents in the previous academic year, students attending the course with daily quizzes significantly improved their academic achievement, expressed as the pass rate at the first examination term (39% vs 62%, respectively, chi(2) test, P=0.006, ) and the average course grade (2.71+/-1.08 vs 3.38+/-1.26, respectively; t test, P<0.001). Despite their frequency and possible associated stress, daily quizzes were associated with better academic success in the anatomy course.

Daily oral iron supplementation during pregnancy

Science.gov (United States)

Peña-Rosas, Juan Pablo; De-Regil, Luz Maria; Dowswell, Therese; Viteri, Fernando E

2014-01-01

Background Iron and folic acid supplementation has been the preferred intervention to improve iron stores and prevent anaemia among pregnant women, and it may also improve other maternal and birth outcomes. Objectives To assess the effects of daily oral iron supplements for pregnant women, either alone or in conjunction with folic acid, or with other vitamins and minerals as a public health intervention. Search methods We searched the Cochrane Pregnancy and Childbirth Group’s Trials Register (2 July 2012). We also searched the WHO International Clinical Trials Registry Platform (ICTRP) (2 July 2012) and contacted relevant organisations for the identification of ongoing and unpublished studies. Selection criteria Randomised or quasi-randomised trials evaluating the effects of oral preventive supplementation with daily iron, iron + folic acid or iron + other vitamins and minerals during pregnancy. Data collection and analysis We assessed the methodological quality of trials using standard Cochrane criteria. Two review authors independently assessed trial eligibility, extracted data and conducted checks for accuracy. Main results We included 60 trials. Forty-three trials, involving more than 27,402 women, contributed data and compared the effects of daily oral supplements containing iron versus no iron or placebo. Overall, women taking iron supplements were less likely to have low birthweight newborns (below 2500 g) compared with controls (8.4% versus 10.2%, average risk ratio (RR) 0.81; 95% confidence interval (CI) 0.68 to 0.97, 11 trials, 8480 women) and mean birthweight was 30.81 g greater for those infants whose mothers received iron during pregnancy (average mean difference (MD) 30.81; 95% CI 5.94 to 55.68, 14 trials, 9385 women). Preventive iron supplementation reduced the risk of maternal anaemia at term by 70% (RR 0.30; 95% CI 0.19 to 0.46, 14 trials, 2199 women) and iron deficiency at term by 57% (RR 0.43; 95% CI 0.27 to 0.66, seven trials, 1256 women

Delayed child-bearing.

Science.gov (United States)

Johnson, Jo-Ann; Tough, Suzanne

2012-01-01

To provide an overview of delayed child-bearing and to describe the implications for women and health care providers. Delayed child-bearing, which has increased greatly in recent decades, is associated with an increased risk of infertility, pregnancy complications, and adverse pregnancy outcome. This guideline provides information that will optimize the counselling and care of Canadian women with respect to their reproductive choices. Maternal age is the most important determinant of fertility, and obstetric and perinatal risks increase with maternal age. Many women are unaware of the success rates or limitations of assisted reproductive technology and of the increased medical risks of delayed child-bearing, including multiple births, preterm delivery, stillbirth, and Caesarean section. This guideline provides a framework to address these issues. Studies published between 2000 and August 2010 were retrieved through searches of PubMed and the Cochrane Library using appropriate key words (delayed child-bearing, deferred pregnancy, maternal age, assisted reproductive technology, infertility, and multiple births) and MeSH terms (maternal age, reproductive behaviour, fertility). The Internet was also searched using similar key words, and national and international medical specialty societies were searched for clinical practice guidelines and position statements. Data were extracted based on the aims, sample, authors, year, and results. The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). The Society of Obstetricians and Gynaecologists of Canada. RECOMMENDATIONS 1. Women who delay child-bearing are at increased risk of infertility. Prospective parents, especially women, should know that their fecundity and fertility begin to decline significantly after 32 years of age. Prospective parents should know that assisted reproductive technologies cannot guarantee a live birth or completely

Environmental Influences on Daily Emergency Admissions in Sickle-Cell Disease Patients

Science.gov (United States)

Mekontso Dessap, Armand; Contou, Damien; Dandine-Roulland, Claire; Hemery, François; Habibi, Anoosha; Charles-Nelson, Anaïs; Galacteros, Frederic; Brun-Buisson, Christian; Maitre, Bernard; Katsahian, Sandrine

2014-01-01

Abstract Previous reports have suggested a role for weather conditions and air pollution on the variability of sickle cell disease (SCD) severity, but large-scale comprehensive epidemiological studies are lacking. In order to evaluate the influence of air pollution and climatic factors on emergency hospital admissions (EHA) in SCD patients, we conducted an 8-year observational retrospective study in 22 French university hospitals in Paris conurbation, using distributed lag non-linear models, a methodology able to flexibly describe simultaneously non-linear and delayed associations, with a multivariable approach. During the 2922 days of the study, there were 17,710 EHA, with a mean daily number of 6.1 ± 2.8. Most environmental factors were significantly correlated to each other. The risk of EHA was significantly associated with higher values of nitrogen dioxide, atmospheric particulate matters, and daily mean wind speed; and with lower values of carbon monoxide, ozone, sulfur dioxide, daily temperature (minimal, maximal, mean, and range), day-to-day mean temperature change, daily bright sunshine, and occurrence of storm. There was a lag effect for 12 of 15 environmental factors influencing hospitalization rate. Multivariate analysis identified carbon monoxide, day-to-day temperature change, and mean wind speed, along with calendar factors (weekend, summer season, and year) as independent factors associated with EHA. In conclusion, most weather conditions and air pollutants assessed were correlated to each other and influenced the rate of EHA in SCD patients. In multivariate analysis, lower carbon monoxide concentrations, day-to-day mean temperature drop and higher wind speed were associated with increased risk of EHA. PMID:25546672

Delays in US mitigation could rule out Paris targets

Science.gov (United States)

Sanderson, Benjamin M.; Knutti, Reto

2017-02-01

Political upsets could stall coordinated international mitigation action, but emissions and investments over the next few years will have long-term consequences. Any delays to mitigation or cuts to renewable energy research by the US will likely render the 2 °C target unachievable if a global precedent is set.

Ignition Delay of Combustible Materials in Normoxic Equivalent Environments

Science.gov (United States)

McAllister, Sara; Fernandez-Pello, Carlos; Ruff, Gary; Urban, David

2009-01-01

Material flammability is an important factor in determining the pressure and composition (fraction of oxygen and nitrogen) of the atmosphere in the habitable volume of exploration vehicles and habitats. The method chosen in this work to quantify the flammability of a material is by its ease of ignition. The ignition delay time was defined as the time it takes a combustible material to ignite after it has been exposed to an external heat flux. Previous work in the Forced Ignition and Spread Test (FIST) apparatus has shown that the ignition delay in the currently proposed space exploration atmosphere (approximately 58.6 kPa and32% oxygen concentration) is reduced by 27% compared to the standard atmosphere used in the Space Shuttle and Space Station. In order to determine whether there is a safer environment in terms of material flammability, a series of piloted ignition delay tests using polymethylmethacrylate (PMMA) was conducted in the FIST apparatus to extend the work over a range of possible exploration atmospheres. The exploration atmospheres considered were the normoxic equivalents, i.e. reduced pressure conditions with a constant partial pressure of oxygen. The ignition delay time was seen to decrease as the pressure was reduced along the normoxic curve. The minimum ignition delay observed in the normoxic equivalent environments was nearly 30% lower than in standard atmospheric conditions. The ignition delay in the proposed exploration atmosphere is only slightly larger than this minimum. Interms of material flammability, normoxic environments with a higher pressure relative to the proposed pressure would be desired.

The evaluation of daily living activities, pressure sores and risk factors.

Science.gov (United States)

Aydın, Gökçen; Mucuk, Salime

2015-01-01

This study was conducted to assess daily living activities, pressure sores and risk factors. This was a descriptive study. The study was conducted at a rehabilitation center with 188 individuals participating in the study. Data were collected with a questionnaire form, Activities of Daily Living Scale (ADLS), Instrumental Activities of Daily Living Scale (IADLS) and Braden Risk Assessment Scale (BRAS). Among the participants, 48.9% were dependent according to activities of daily living and 71.8% were dependent on instrumental activities of daily living. It was noted that 4.8% had pressure sores and 38.8% were at high risk. A strong and positive correlation was found among ADLS, IADLS, and BRAS scores (p pressure sores (p pressure sores. Individuals who are treated at rehabilitation centers should be periodically assessed in terms of risk. Pressure sore development can be prevented with appropriate nursing interventions. To reduce the risk of developing pressure sores, nurses should describe the individual's degree of dependency according to ADLS and IADLS and initiate preventive nursing care. © 2014 Association of Rehabilitation Nurses.

On the probability distribution of daily streamflow in the United States

Science.gov (United States)

Blum, Annalise G.; Archfield, Stacey A.; Vogel, Richard M.

2017-06-01

Daily streamflows are often represented by flow duration curves (FDCs), which illustrate the frequency with which flows are equaled or exceeded. FDCs have had broad applications across both operational and research hydrology for decades; however, modeling FDCs has proven elusive. Daily streamflow is a complex time series with flow values ranging over many orders of magnitude. The identification of a probability distribution that can approximate daily streamflow would improve understanding of the behavior of daily flows and the ability to estimate FDCs at ungaged river locations. Comparisons of modeled and empirical FDCs at nearly 400 unregulated, perennial streams illustrate that the four-parameter kappa distribution provides a very good representation of daily streamflow across the majority of physiographic regions in the conterminous United States (US). Further, for some regions of the US, the three-parameter generalized Pareto and lognormal distributions also provide a good approximation to FDCs. Similar results are found for the period of record FDCs, representing the long-term hydrologic regime at a site, and median annual FDCs, representing the behavior of flows in a typical year.

A low-delay 8 Kb/s backward-adaptive CELP coder

Science.gov (United States)

Neumeyer, L. G.; Leblanc, W. P.; Mahmoud, S. A.

1990-01-01

Code excited linear prediction coding is an efficient technique for compressing speech sequences. Communications quality of speech can be obtained at bit rates below 8 Kb/s. However, relatively large coding delays are necessary to buffer the input speech in order to perform the LPC analysis. A low delay 8 Kb/s CELP coder is introduced in which the short term predictor is based on past synthesized speech. A new distortion measure that improves the tracking of the formant filter is discussed. Formal listening tests showed that the performance of the backward adaptive coder is almost as good as the conventional CELP coder.

Improved result on stability analysis of discrete stochastic neural networks with time delay

International Nuclear Information System (INIS)

Wu Zhengguang; Su Hongye; Chu Jian; Zhou Wuneng

2009-01-01

This Letter investigates the problem of exponential stability for discrete stochastic time-delay neural networks. By defining a novel Lyapunov functional, an improved delay-dependent exponential stability criterion is established in terms of linear matrix inequality (LMI) approach. Meanwhile, the computational complexity of the newly established stability condition is reduced because less variables are involved. Numerical example is given to illustrate the effectiveness and the benefits of the proposed method.

Classic conditioning in aged rabbits: delay, trace, and long-delay conditioning.

Science.gov (United States)

Solomon, P R; Groccia-Ellison, M E

1996-06-01

Young (0.5 years) and aged (2+, 3+, and 4+ years) rabbits underwent acquisition of the classically conditioned nictitating membrane response in a delay (500-ms conditioned stimulus [CS], 400-ms interstimulus interval [ISI]), long-delay (1,000-ms CS, 900-ms ISI), or trace (500-ms CS, 400-ms stimulus-free period) paradigm. Collapsing across age groups, there is a general tendency for animals to acquire trace conditioning more slowly than delay conditioning. Collapsing across conditioning paradigms, there is a general tendency for aged animals to acquire more slowly than younger animals. Of greater significance, however, are the age differences in the different conditioning paradigms. In the delay and long-delay paradigms, significant conditioning deficits first appeared in the 4(+)-year-old group. In the trace conditioning paradigm, significant conditioning deficits became apparent in the 2(+)-year-old animals.

A novel stabilization condition for T-S polynomial fuzzy system with time-delay:A sum-of-squares approach

OpenAIRE

Tsai, Shun Hung; Chen, Yu-An; Chen, Yu-Wen; Lo, Ji-Chang; Lam, Hak-Keung

2017-01-01

A novel stabilization problem for T-S polynomial fuzzy system with time-delay is investigated in this paper. Firstly, a polynomial fuzzy controller for T-S polynomial fuzzy system with time-delay is proposed. In addition, based on polynomial Lyapunov-Krasovskii function and the developed polynomial slack variable matrices, a novel stabilization condition for T-S polynomial fuzzy system with time-delay is presented in terms of sum-of-square (SOS) form. Lastly, nonlinear system with time-delay ...

Travelling wavefronts of a generalized Fisher equation with spatio-temporal delay

International Nuclear Information System (INIS)

Jin Chunhua; Yin Jingxue; Wang Yifu

2009-01-01

We discuss a generalized Fisher equation with a convolution term which introduces a time-delay in the nonlinearity. Special attention is paid to the existence and the asymptotic behavior of travelling wavefronts connecting two uniform steady states.

Get the gist? The effects of processing depth on false recognition in short-term and long-term memory.

Science.gov (United States)

Flegal, Kristin E; Reuter-Lorenz, Patricia A

2014-07-01

Gist-based processing has been proposed to account for robust false memories in the converging-associates task. The deep-encoding processes known to enhance verbatim memory also strengthen gist memory and increase distortions of long-term memory (LTM). Recent research has demonstrated that compelling false memory illusions are relatively delay-invariant, also occurring under canonical short-term memory (STM) conditions. To investigate the contributions of gist to false memory at short and long delays, processing depth was manipulated as participants encoded lists of four semantically related words and were probed immediately, following a filled 3- to 4-s retention interval, or approximately 20 min later, in a surprise recognition test. In two experiments, the encoding manipulation dissociated STM and LTM on the frequency, but not the phenomenology, of false memory. Deep encoding at STM increases false recognition rates at LTM, but confidence ratings and remember/know judgments are similar across delays and do not differ as a function of processing depth. These results suggest that some shared and some unique processes underlie false memory illusions at short and long delays.

The ecological rationality of delay tolerance: insights from capuchin monkeys.

Science.gov (United States)

Addessi, Elsa; Paglieri, Fabio; Focaroli, Valentina

2011-04-01

Both human and non-human animals often face decisions between options available at different times, and the capacity of delaying gratification has usually been considered one of the features distinguishing humans from other animals. However, this characteristic can widely vary across individuals, species, and types of task and it is still unclear whether it is accounted for by phylogenetic relatedness, feeding ecology, social structure, or metabolic rate. To disentangle these hypotheses, we evaluated temporal preferences in capuchin monkeys, South-American primates that, despite splitting off from human lineage approximately 35 million years ago, show striking behavioural analogies with the great apes. Then, we compared capuchins' performance with that of the other primate species tested so far with the same procedure. Overall, capuchins showed a delay tolerance significantly higher than closely related species, such as marmosets and tamarins, and comparable to that shown by great apes. Capuchins' tool use abilities might explain their comparatively high preference for delayed options in inter-temporal choices. Moreover, as in humans, capuchin females showed a greater delay tolerance than males, possibly because of their less opportunistic foraging style. Thus, our results shed light on the evolutionary origins of self-control supporting explanations of delay tolerance in terms of feeding ecology. Copyright © 2010 Elsevier B.V. All rights reserved.

Delay-Limited Capacity in the Low Power Regime

KAUST Repository

Rezki, Zouheir

2016-02-11

Outage performance of the M-block fading with additive white Gaussian noise (BF-AWGN) is investigated in the low-power regime. We consider delay-constrained constant-rate communications with perfect channel state information (CSI) at both the transmitter and the receiver (CSI-TR), under a shortterm power constraint (STPC) and a long-term power constraint (LTPC). Subject to STPC, we show that selection diversity that allocates all the power to the strongest block is asymptotically optimal. Then, we provide a simple characterization of the outage probability in the regime of interest. We quantify the reward due to CSI-TR over the constant-rate constant-power scheme and show that this reward increases with the delay constraint. For instance, for Rayleigh fading, we find that a power gain up to 4.3 dB is achievable. Subject to LTPC, we show that the above guidelines still holds and that the outage performance improves due to the flexibility of the LTPC over the STPC. More interestingly, we prove that LTPC allows zero-outage communication even at low SNR and characterize the delaylimited capacity at low SNR in a simple form. More precisely, we establish that the delay-limited capacity scales linearly with the power constraint, for a given M < 1. Our framework highlights the benefit of fading at low SNR as the delay-limited capacity may outperform the AWGN capacity. For instance, for Rayleigh fading and with M = 3, the delay-limited capacity is 16% higher than the capacity of an AWGN channel.

Global synchronization criteria with channel time-delay for chaotic time-delay system

International Nuclear Information System (INIS)

Sun Jitao

2004-01-01

Based on the Lyapunov stabilization theory, matrix measure, and linear matrix inequality (LMIs), this paper studies the chaos synchronization of time-delay system using the unidirectional linear error feedback coupling with time-delay. Some generic conditions of chaos synchronization with time-delay in the transmission channel is established. The chaotic Chua's circuit is used for illustration, where the coupling parameters are determined according to the criteria under which the global chaos synchronization of the time-delay coupled systems is achieved

Determinants of developmental delay in infants aged 12 months.

Science.gov (United States)

Slykerman, Rebecca F; Thompson, John M D; Clark, Phillipa M; Becroft, David M O; Robinson, Elizabeth; Pryor, Jan E; Wild, Chris J; Mitchell, Edwin A

2007-03-01

The aim of this study was to determine which demographic, maternal, obstetric and postnatal variables were associated with achievement of developmental milestones at the age of 12 months in term infants. Mothers and babies were enrolled in the Auckland Birthweight Collaborative Study shortly after birth. All infants were full term (gestation >or= 37 weeks). Approximately half of the sample were small for gestational age (SGA = birthweight 10th percentile). A maternal interview was conducted soon after birth. Phase 2 of the study occurred 12 months later when mothers were sent a postal questionnaire requesting information about the child's health and development during the first year of life using the Denver Prescreening Developmental Questionnaire. Seven hundred and forty-four (85.4%) European mothers returned the postal questionnaire. SGA children were not at increased risk of developmental delay at 12 months of age. In a sample representative of New Zealand European children, after adjustment for the effects of potential confounders, maternal smoking during pregnancy (OR = 2.1 [95% CI 1.1, 4.0]), maternal smoking during the first year of life (OR = 1.9 [95% CI 1.0, 3.8]) and low levels of satisfaction with parenting (OR = 2.4 [95% CI 1.1, 5.2]) were associated with significantly increased risk of developmental delay. In the subgroup of SGA children, maternal smoking during pregnancy (OR = 2.9 [95% CI 1.4, 6.2]), high levels of stress associated with parenting (OR = 2.2 [95% CI 1.2, 4.0]), and low levels of satisfaction with parenting (OR = 4.3 [95% CI 1.3, 13.5]) were significantly associated with developmental delay after adjustment for the effects of potential confounders. In conclusion, maternal and postnatal factors were better predictors of developmental delay than demographic variables.

Delayed minocycline but not delayed mild hypothermia protects against embolic stroke

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Noor Raza

2002-04-01

Full Text Available Abstract Background Inflammatory reactions occurring in the brain after ischemia may contribute to secondary damage. In the present study, effects of minocycline, an anti-inflammatory agent, alone or in combination with mild hypothermia on focal embolic cerebral ischemia have been examined. Methods Focal ischemic injury was induced by embolizing a preformed clot into the middle cerebral artery (MCA. Infarction volume was measured at 48 h after the injury. Mortality was also recorded. Results Delayed administration of minocycline alone or delayed minocycline plus delayed mild hypothermia reduced the infarction volume significantly. However, delayed mild hypothermia alone was not protective and delayed mild hypothermia in combination with minocycline did not show any additive effect. Conclusions These results suggest that minocycline is beneficial in focal ischemic brain injury, and the lack of the enhanced neuroprotection may be due to the brief exposure to hypothermia.

Enhancing endogenous stem cells in the newbornvia delayed umbilical cord clamping

Institute of Scientific and Technical Information of China (English)

Christopher Lawton; Sandra Acosta; Nate Watson; Chiara Gonzales-Portillo; hTeo Diamandis; Naoki Tajiri; Yuji Kaneko; Paul R. Sanberg; Cesar V. Borlongan

2015-01-01

There is currently no consensus among clinicians and scientists over the appropriate or optimal timing for umbilical cord clamping. However, many clinical studies have suggested that delayed cord clamping is associated with various neonatal beneifts including increased blood volume, reduced need for blood transfusion, increased cerebral oxygenation in pre-term infants, and decreased frequency of iron deifciency anemia in term infants. Human umbilical cord blood con-tains signiifcant amounts of stem and progenitor cells and is currently used in the treatment of several life-threatening diseases. We propose that delayed cord clamping be encouraged as it en-hances blood lfow from the placenta to the neonate, which is accompanied by an increase supply of valuable stem and progenitor cells, as well as may improve blood oxygenation and increase blood volume, altogether reducing the infant’s susceptibility to both neonatal and age-related diseases.

Moving toward more perfect unions: daily and long-term consequences of approach and avoidance goals in romantic relationships.

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Impett, Emily A; Gordon, Amie M; Kogan, Aleksandr; Oveis, Christopher; Gable, Shelly L; Keltner, Dacher

2010-12-01

In 2 daily experience studies and a laboratory study, the authors test predictions from approach-avoidance motivational theory to understand how dating couples can maintain feelings of relationship satisfaction in their daily lives and over the course of time. Approach goals were associated with increased relationship satisfaction on a daily basis and over time, particularly when both partners were high in approach goals. Avoidance goals were associated with decreases in relationship satisfaction over time, and people were particularly dissatisfied when they were involved with a partner with high avoidance goals. People high in approach goals and their partners were rated as relatively more satisfied and responsive to a partner's needs by outside observers in the lab, whereas people with high avoidance goals and their partners were rated as less satisfied and responsive. Positive emotions mediated the link between approach goals and daily satisfaction in both studies, and responsiveness to the partner's needs was an additional behavioral mechanism in Study 2. Implications of these findings for approach-avoidance motivational theory and for the maintenance of satisfying relationships over time are discussed. PsycINFO Database Record (c) 2010 APA, all rights reserved.

Desert Dust Outbreaks in Southern Europe: Contribution to Daily PM10 Concentrations and Short-Term Associations with Mortality and Hospital Admissions

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Stafoggia, Massimo; Zauli-Sajani, Stefano; Pey, Jorge; Samoli, Evangelia; Alessandrini, Ester; Basagaña, Xavier; Cernigliaro, Achille; Chiusolo, Monica; Demaria, Moreno; Díaz, Julio; Faustini, Annunziata; Katsouyanni, Klea; Kelessis, Apostolos G.; Linares, Cristina; Marchesi, Stefano; Medina, Sylvia; Pandolfi, Paolo; Pérez, Noemí; Querol, Xavier; Randi, Giorgia; Ranzi, Andrea; Tobias, Aurelio; Forastiere, Francesco

2015-01-01

Background: Evidence on the association between short-term exposure to desert dust and health outcomes is controversial. Objectives: We aimed to estimate the short-term effects of particulate matter ≤ 10 μm (PM10) on mortality and hospital admissions in 13 Southern European cities, distinguishing between PM10 originating from the desert and from other sources. Methods: We identified desert dust advection days in multiple Mediterranean areas for 2001–2010 by combining modeling tools, back-trajectories, and satellite data. For each advection day, we estimated PM10 concentrations originating from desert, and computed PM10 from other sources by difference. We fitted city-specific Poisson regression models to estimate the association between PM from different sources (desert and non-desert) and daily mortality and emergency hospitalizations. Finally, we pooled city-specific results in a random-effects meta-analysis. Results: On average, 15% of days were affected by desert dust at ground level (desert PM10 > 0 μg/m3). Most episodes occurred in spring–summer, with increasing gradient of both frequency and intensity north–south and west–east of the Mediterranean basin. We found significant associations of both PM10 concentrations with mortality. Increases of 10 μg/m3 in non-desert and desert PM10 (lag 0–1 days) were associated with increases in natural mortality of 0.55% (95% CI: 0.24, 0.87%) and 0.65% (95% CI: 0.24, 1.06%), respectively. Similar associations were estimated for cardio-respiratory mortality and hospital admissions. Conclusions: PM10 originating from the desert was positively associated with mortality and hospitalizations in Southern Europe. Policy measures should aim at reducing population exposure to anthropogenic airborne particles even in areas with large contribution from desert dust advections. Citation: Stafoggia M, Zauli-Sajani S, Pey J, Samoli E, Alessandrini E, Basagaña X, Cernigliaro A, Chiusolo M, Demaria M, Díaz J, Faustini A

Desert Dust Outbreaks in Southern Europe: Contribution to Daily PM₁₀ Concentrations and Short-Term Associations with Mortality and Hospital Admissions.

Science.gov (United States)

Stafoggia, Massimo; Zauli-Sajani, Stefano; Pey, Jorge; Samoli, Evangelia; Alessandrini, Ester; Basagaña, Xavier; Cernigliaro, Achille; Chiusolo, Monica; Demaria, Moreno; Díaz, Julio; Faustini, Annunziata; Katsouyanni, Klea; Kelessis, Apostolos G; Linares, Cristina; Marchesi, Stefano; Medina, Sylvia; Pandolfi, Paolo; Pérez, Noemí; Querol, Xavier; Randi, Giorgia; Ranzi, Andrea; Tobias, Aurelio; Forastiere, Francesco

2016-04-01

Evidence on the association between short-term exposure to desert dust and health outcomes is controversial. We aimed to estimate the short-term effects of particulate matter ≤ 10 μm (PM10) on mortality and hospital admissions in 13 Southern European cities, distinguishing between PM10 originating from the desert and from other sources. We identified desert dust advection days in multiple Mediterranean areas for 2001-2010 by combining modeling tools, back-trajectories, and satellite data. For each advection day, we estimated PM10 concentrations originating from desert, and computed PM10 from other sources by difference. We fitted city-specific Poisson regression models to estimate the association between PM from different sources (desert and non-desert) and daily mortality and emergency hospitalizations. Finally, we pooled city-specific results in a random-effects meta-analysis. On average, 15% of days were affected by desert dust at ground level (desert PM10 > 0 μg/m3). Most episodes occurred in spring-summer, with increasing gradient of both frequency and intensity north-south and west-east of the Mediterranean basin. We found significant associations of both PM10 concentrations with mortality. Increases of 10 μg/m3 in non-desert and desert PM10 (lag 0-1 days) were associated with increases in natural mortality of 0.55% (95% CI: 0.24, 0.87%) and 0.65% (95% CI: 0.24, 1.06%), respectively. Similar associations were estimated for cardio-respiratory mortality and hospital admissions. PM10 originating from the desert was positively associated with mortality and hospitalizations in Southern Europe. Policy measures should aim at reducing population exposure to anthropogenic airborne particles even in areas with large contribution from desert dust advections. Stafoggia M, Zauli-Sajani S, Pey J, Samoli E, Alessandrini E, Basagaña X, Cernigliaro A, Chiusolo M, Demaria M, Díaz J, Faustini A, Katsouyanni K, Kelessis AG, Linares C, Marchesi S, Medina S, Pandolfi P, P�

Delayed puberty in girls

Science.gov (United States)

... sexual development - girls; Pubertal delay - girls; Constitutional delayed puberty ... In most cases of delayed puberty, growth changes just begin later than usual, sometimes called a late bloomer. Once puberty begins, it progresses normally. This pattern runs ...

Closeness-Centrality-Based Synchronization Criteria for Complex Dynamical Networks With Interval Time-Varying Coupling Delays.

Science.gov (United States)

Park, Myeongjin; Lee, Seung-Hoon; Kwon, Oh-Min; Seuret, Alexandre

2017-09-06

This paper investigates synchronization in complex dynamical networks (CDNs) with interval time-varying delays. The CDNs are representative of systems composed of a large number of interconnected dynamical units, and for the purpose of the mathematical analysis, the leading work is to model them as graphs whose nodes represent the dynamical units. At this time, we take note of the importance of each node in networks. One way, in this paper, is that the closeness-centrality mentioned in the field of social science is grafted onto the CDNs. By constructing a suitable Lyapunov-Krasovskii functional, and utilizing some mathematical techniques, the sufficient and closeness-centrality-based conditions for synchronization stability of the networks are established in terms of linear matrix inequalities. Ultimately, the use of the closeness-centrality can be weighted with regard to not only the interconnection relation among the nodes, which was utilized in the existing works but also more information about nodes. Here, the centrality will be added as the concerned information. Moreover, to avoid the computational burden causing the nonconvex term including the square of the time-varying delay, how to deal with it is applied by estimating it to the convex term including time-varying delay. Finally, two illustrative examples are given to show the advantage of the closeness-centrality in point of the robustness on time-delay.

Controlled Nonlinear Stochastic Delay Equations: Part II: Approximations and Pipe-Flow Representations

International Nuclear Information System (INIS)

Kushner, Harold J.

2012-01-01

This is the second part of a work dealing with key issues that have not been addressed in the modeling and numerical optimization of nonlinear stochastic delay systems. We consider new classes of models, such as those with nonlinear functions of several controls (such as products), each with is own delay, controlled random Poisson measure driving terms, admissions control with delayed retrials, and others. Part I was concerned with issues concerning the class of admissible controls and their approximations, since the classical definitions are inadequate for our models. This part is concerned with transportation equation representations and their approximations. Such representations of nonlinear stochastic delay models have been crucial in the development of numerical algorithms with much reduced memory and computational requirements. The representations for the new models are not obvious and are developed. They also provide a template for the adaptation of the Markov chain approximation numerical methods.

Photonic single nonlinear-delay dynamical node for information processing

Science.gov (United States)

Ortín, Silvia; San-Martín, Daniel; Pesquera, Luis; Gutiérrez, José Manuel

2012-06-01

An electro-optical system with a delay loop based on semiconductor lasers is investigated for information processing by performing numerical simulations. This system can replace a complex network of many nonlinear elements for the implementation of Reservoir Computing. We show that a single nonlinear-delay dynamical system has the basic properties to perform as reservoir: short-term memory and separation property. The computing performance of this system is evaluated for two prediction tasks: Lorenz chaotic time series and nonlinear auto-regressive moving average (NARMA) model. We sweep the parameters of the system to find the best performance. The results achieved for the Lorenz and the NARMA-10 tasks are comparable to those obtained by other machine learning methods.

Delayed Puberty (For Teens)

Science.gov (United States)

... Safe Videos for Educators Search English Español Delayed Puberty KidsHealth / For Teens / Delayed Puberty What's in this ... wonder if there's anything wrong. What Is Delayed Puberty? Puberty is the time when your body grows ...

Stabilization of Networked Control Systems with Variable Delays and Saturating Inputs

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M. Mahmodi Kaleybar

2014-06-01

Full Text Available In this paper, improved conditions for the synthesis of static state-feedback controller are derived to stabilize networked control systems (NCSs subject to actuator saturation. Both of the data packet latency and dropout which deteriorate the performance of the closed-loop system are considered in the NCS model via variable delays. Two different techniques are employed to incorporate actuator saturation in the system description. Utilizing Lyapunov-Krasovskii Theorem, delay-dependent conditions are obtained in terms of linear matrix inequalities (LMIs to determine the static feedback gain. Moreover, an optimization problem is formulated in order to find the less conservative estimate for the region of attraction corresponding to different maximum allowable delays. Numerical examples are introduced to demonstrate the effectiveness and advantages of the proposed schemes.

Pathophysiology and therapy of irinotecan-induced delayed-onset diarrhea in patients with advanced colorectal cancer: a prospective assessment.

Science.gov (United States)

Saliba, F; Hagipantelli, R; Misset, J L; Bastian, G; Vassal, G; Bonnay, M; Herait, P; Cote, C; Mahjoubi, M; Mignard, D; Cvitkovic, E

1998-08-01

Irinotecan (CPT-11), a camptothecin derivative, has shown efficacy against colorectal cancer. Delayed-onset diarrhea is its main limiting toxicity. The aim of this study was to determine the pathophysiology of CPT-11-induced delayed-onset diarrhea and assess the efficacy of combined antidiarrheal medication in a phase II, prospective, successive-cohorts, open study. Twenty-eight patients with advanced colorectal cancer refractory to fluorouracil (5-FU) therapy received CPT-11 350 mg/m2 every 3 weeks. The first cohort of 14 consecutive patients explored for the mechanism of diarrhea received acetorphan (a new enkephalinase inhibitor) 100 mg three times daily; the second 14-patient cohort received, in addition to acetorphan, loperamide 4 mg three times daily. Before treatment, and if late diarrhea occurred, patients underwent colon mucosal biopsies for CPT-11 and topoisomerase I levels; intestinal transit time; fecalogram; fat and protein excretion; alpha1-antitrypsin clearance; D-xylose test; blood levels for vasoactive intestinal polypeptide, glucagon, gastrin, somatostatin, prostaglandin E2, and carboxylesterase; CPT-11/SN-38 and SN-38 glucuronide pharmacokinetics; and stool cultures. Delayed-onset diarrhea occurred during the first three treatment cycles in 23 patients (82%). Electrolyte fecal measurements showed a negative or small osmotic gap in nine of nine patients and an increased alpha1-antitrypsin clearance in six of six patients. There were no modifications in stool cultures or hormonal dysfunction. Four of 11 patients (36%) with delayed-onset diarrhea in the first cohort responded to acetorphan, whereas nine of 10 patients (90%) responded to the combination of acetorphan and loperamide (P diarrhea is caused by a secretory mechanism with an exudative component. Early combined treatment with loperamide and acetorphan seems effective in controlling the diarrheal episodes.

A Review of Interventions Designed to Increase Sharing Behaviors in Children with Social Delays or Deficits

Science.gov (United States)

Lane, Justin D.; Ledford, Jennifer R.

2016-01-01

Sharing materials is a complex social behavior that may lead to long-term development of friendships and concomitant increases in related prosocial behaviors. Given the complexities of sharing behaviors, children with social delays or deficits may not recognize when, how, and with whom to share. Because children with social delays or deficits,…

The relationships between short-term exposure to particulate matter and mortality in Korea: impact of particulate matter exposure metrics for sub-daily exposures

International Nuclear Information System (INIS)

Son, Ji-Young; Bell, Michelle L

2013-01-01

Most studies of short-term particulate matter (PM) exposure use 24 h averages. However, other pollutants have stronger effects in shorter timeframes, which has influenced policy (e.g., ozone 8 h maximum). The selection of appropriate exposure timeframes is important for effective regulation. The US EPA identified health effects for sub-daily PM exposures as a critical research need. Unlike most areas, Seoul, Korea has hourly measurements of PM 10 , although not PM 2.5 . We investigated PM 10 and mortality (total, cardiovascular, respiratory) in Seoul (1999–2009) considering sub-daily exposures: 24 h, daytime (7 am–8 pm), morning (7–10 am), nighttime (8 pm–7 am), and 1 h daily maximum. We applied Poisson generalized linear modeling adjusting for temporal trends and meteorology. All PM 10 metrics were significantly associated with total mortality. Compared to other exposure timeframes, morning exposure had the most certain effect on total mortality (based on statistical significance). Increases of 10 μg m −3 in 24 h, daytime, morning, nighttime, and 1 h maximum PM 10 were associated with 0.15% (95% confidence interval 0.02–0.28%), 0.14% (0.01–0.27%), 0.10% (0.03–0.18%), 0.12% (0.03–0.22%), and 0.10% (0.00–0.21%) increases in total mortality, respectively. PM 10 was significantly associated with cardiovascular mortality for 24 h, morning, and nighttime exposures. We did not identify significant associations with respiratory mortality. The results support use of a 24 h averaging time as an appropriate metric for health studies and regulation, particularly for PM 10 and mortality. (letter)

Expressive language of two year-old pre-term and full-term children.

Science.gov (United States)

Isotani, Selma Mie; Azevedo, Marisa Frasson de; Chiari, Brasília Maria; Perissinoto, Jacy

2009-01-01

expressive language of pre-term children. to compare the expressive vocabulary of two year-old children born prematurely, to that of those born at term. the study sample was composed by 118 speech-language assessment protocols, divided in two groups: the pre-term group (PTG) composed by 58 underweight premature children followed by a multi-professional team at the Casa do Prematuro (House of Premature Children) at Unifesp, and the full-term group (FTG) composed by 60 full-term born children. In order to evaluate the expressive language of these children, the Lave - Lista de Avaliação do Vocabulário Expressivo (Assessment List of the Expressive Vocabulary) was used. The Lave is an adaptation of the LDS - Language Development Survey - for the Brazilian Portuguese Language. The Lave investigates the expressive language and detects delays in oral language. children born underweight and prematurely present a greater occurrence of expressive language delay, 27.6%. These pre-term children present significantly lower expressive vocabulary and phrasal extension than children of the same age born at full-term in all semantic categories. Family income proved to be positively associated to phrasal extension, as well as to gestational age and weight at birth; thus indicating the effect of these adverse conditions still during the third year of age. The audiological status was associated to word utterances in the PTG. children born prematurely and underweight are at risk in terms of vocabulary development; this determines the need for speech-therapy intervention programs.

A STUDY OF IMPACT OF DETERMINANTS OF PATIENTS AND HEALTH SYSTEM DELAY ON TUBERCULOSIS DIAGNOSIS AND TREATMENT IN BANGALORE

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Jagadish Siddalinga Devaru

2013-01-01

Full Text Available Setting: TU/DMCs of Bangalore city. India. All new sputum positive patients registered to the selected TU/DMCs were interviewed. A total of 468 patients aged above 20 years were enrolled. The study period was from January to June 2009. Objectives: To track the delay in diagnosis and treatment of patients reporting to tuberculosis units and microscopy centers. Design: A cross sectional study. TU/DMCs were randomly selected. A pretested questionnaire was administered to collect data. Results: The study population had 326 (69.7% males. The mean age of study population was 38.5 years. 74.4% were married, 20.7% were illiterates, 27.8% were daily wagers, 10.5% were unemployed. The median and mean total delays from development of cough to diagnosis were 41 days and 36.04 days; the median and mean patient delay was 24 days and 20.7 days, and health system delay was 18 and 15.31 days respectively. There was a significant difference among the different age group of patients with older people having longer patient delay (p<0.0001. Lower income, illiteracy, unemployment, showed significant association with patients delay (p<0.0001. Alcohol intake and smoking habit among the male patients had significant association for longer patient delay (p=0.00004. Health seeking behavior like self medication, also had longer patient delay. Other socio demographic factors had no significant influence on the patient delay. Longer health system delay was found among patients who visited general practitioners and Ayurvedic medicine. Conclusion: More specific and effective health education of the general public on tuberculosis and seeking of appropriate medical consultation are likely to improve case detection.

A STUDY OF IMPACT OF DETERMINANTS OF PATIENTS AND HEALTH SYSTEM DELAY ON TUBERCULOSIS DIAGNOSIS AND TREATMENT IN BANGALORE

Directory of Open Access Journals (Sweden)

Jagadish Siddalinga Devaru

2012-12-01

Full Text Available Setting: TU/DMCs of Bangalore city. India. All new sputum positive patients registered to the selected TU/DMCs were interviewed. A total of 468 patients aged above 20 years were enrolled. The study period was from January to June 2009. Objectives: To track the delay in diagnosis and treatment of patients reporting to tuberculosis units and microscopy centers. Design: A cross sectional study. TU/DMCs were randomly selected. A pretested questionnaire was administered to collect data. Results: The study population had 326 (69.7% males. The mean age of study population was 38.5 years. 74.4% were married, 20.7% were illiterates, 27.8% were daily wagers, 10.5% were unemployed. The median and mean total delays from development of cough to diagnosis were 41 days and 36.04 days; the median and mean patient delay was 24 days and 20.7 days, and health system delay was 18 and 15.31 days respectively. There was a significant difference among the different age group of patients with older people having longer patient delay (p<0.0001. Lower income, illiteracy, unemployment, showed significant association with patients delay (p<0.0001. Alcohol intake and smoking habit among the male patients had significant association for longer patient delay (p=0.00004. Health seeking behavior like self medication, also had longer patient delay. Other socio demographic factors had no significant influence on the patient delay. Longer health system delay was found among patients who visited general practitioners and Ayurvedic medicine. Conclusion: More specific and effective health education of the general public on tuberculosis and seeking of appropriate medical consultation are likely to improve case detection.

Delay-Dependent Stability Analysis of Uncertain Fuzzy Systems with State and Input Delays under Imperfect Premise Matching

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Zejian Zhang

2013-01-01

Full Text Available This paper discusses the stability and stabilization problem for uncertain T-S fuzzy systems with time-varying state and input delays. A new augmented Lyapunov function with an additional triple-integral term and different membership functions of the fuzzy models and fuzzy controllers are introduced to derive the stability criterion, which is less conservative than the existing results. Moreover, a new flexibility design method is also provided. Some numerical examples are given to demonstrate the effectiveness and less conservativeness of the proposed method.

Factors Affecting Daily Cochlear Implant Use in Children: Datalogging Evidence.

Science.gov (United States)

Easwar, Vijayalakshmi; Sanfilippo, Joseph; Papsin, Blake; Gordon, Karen

Children with profound hearing loss can gain access to sound through cochlear implants (CIs), but these devices must be worn consistently to promote auditory development. Although subjective parent reports have identified several factors limiting long-term CI use in children, it is also important to understand the day-to-day issues which may preclude consistent device use. In the present study, objective measures gathered through datalogging software were used to quantify the following in children: (1) number of hours of CI use per day, (2) practical concerns including repeated disconnections between the external transmission coil and the internal device (termed "coil-offs"), and (3) listening environments experienced during daily use. This study aimed to (1) objectively measure daily CI use and factors influencing consistent device use in children using one or two CIs and (2) evaluate the intensity levels and types of listening environments children are exposed to during daily CI use. Retrospective analysis. Measures of daily CI use were obtained from 146 pediatric users of Cochlear Nucleus 6 speech processors. The sample included 5 unilateral, 40 bimodal, and 101 bilateral CI users (77 simultaneously and 24 sequentially implanted). Daily CI use, duration, and frequency of coil-offs per day, and the time spent in multiple intensity ranges and environment types were extracted from the datalog saved during clinic appointments. Multiple regression analyses were completed to predict daily CI use based on child-related demographic variables, and to evaluate the effects of age on coil-offs and environment acoustics. Children used their CIs for 9.86 ± 3.43 hr on average on a daily basis, with use exceeding 9 hr per day in ∼64% of the children. Daily CI use reduced significantly with increasing durations of coil-off (p = 0.027) and increased significantly with longer CI experience (p Listening environments of all children typically ranged between 50 and 70 d

Reward acts as a signal to control delay-period activity in delayed-response tasks.

Science.gov (United States)

Ichihara-Takeda, Satoe; Takeda, Kazuyoshi; Funahashi, Shintaro

2010-03-31

Prefrontal delay-period activity represents a neural mechanism for the active maintenance of information and needs to be controlled by some signal to appropriately operate working memory. To examine whether reward-delivery acts as this signal, the effects of delay-period activity in response to unexpected reward-delivery were examined by analyzing single-neuron activity recorded in the primate dorsolateral prefrontal cortex. Among neurons that showed delay-period activity, 34% showed inhibition of this activity in response to unexpected reward-delivery. The delay-period activity of these neurons was affected by the expectation of reward-delivery. The strength of the reward signal in controlling the delay-period activity is related to the strength of the effect of reward information on the delay-period activity. These results indicate that reward-delivery acts as a signal to control delay-period activity.

Daily Weather Records

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National Oceanic and Atmospheric Administration, Department of Commerce — These daily weather records were compiled from a subset of stations in the Global Historical Climatological Network (GHCN)-Daily dataset. A weather record is...

Delay-dependent exponential stability of cellular neural networks with time-varying delays

International Nuclear Information System (INIS)

Zhang Qiang; Wei Xiaopeng; Xu Jin

2005-01-01

The global exponential stability of cellular neural networks (CNNs) with time-varying delays is analyzed. Two new sufficient conditions ensuring global exponential stability for delayed CNNs are obtained. The conditions presented here are related to the size of delay. The stability results improve the earlier publications. Two examples are given to demonstrate the effectiveness of the obtained results

A delay-dependent LMI approach to dynamics analysis of discrete-time recurrent neural networks with time-varying delays

International Nuclear Information System (INIS)

Song, Qiankun; Wang, Zidong

2007-01-01

In this Letter, the analysis problem for the existence and stability of periodic solutions is investigated for a class of general discrete-time recurrent neural networks with time-varying delays. For the neural networks under study, a generalized activation function is considered, and the traditional assumptions on the boundedness, monotony and differentiability of the activation functions are removed. By employing the latest free-weighting matrix method, an appropriate Lyapunov-Krasovskii functional is constructed and several sufficient conditions are established to ensure the existence, uniqueness, and globally exponential stability of the periodic solution for the addressed neural network. The conditions are dependent on both the lower bound and upper bound of the time-varying time delays. Furthermore, the conditions are expressed in terms of the linear matrix inequalities (LMIs), which can be checked numerically using the effective LMI toolbox in MATLAB. Two simulation examples are given to show the effectiveness and less conservatism of the proposed criteria

Managing Daily Life

Science.gov (United States)

... Duchenne / Managing Daily Life Print Email Managing Daily Life Environmental accessibility As the person with Duchenne starts ... such as wider doorways and ramps, can make life easier once the person with Duchenne cannot climb ...

Global exponential stability for reaction-diffusion recurrent neural networks with multiple time varying delays

International Nuclear Information System (INIS)

Lou, X.; Cui, B.

2008-01-01

In this paper we consider the problem of exponential stability for recurrent neural networks with multiple time varying delays and reaction-diffusion terms. The activation functions are supposed to be bounded and globally Lipschitz continuous. By means of Lyapunov functional, sufficient conditions are derived, which guarantee global exponential stability of the delayed neural network. Finally, a numerical example is given to show the correctness of our analysis. (author)

Multipulse dynamics of a passively mode-locked semiconductor laser with delayed optical feedback

Science.gov (United States)

Jaurigue, Lina; Krauskopf, Bernd; Lüdge, Kathy

2017-11-01

Passively mode-locked semiconductor lasers are compact, inexpensive sources of short light pulses of high repetition rates. In this work, we investigate the dynamics and bifurcations arising in such a device under the influence of time delayed optical feedback. This laser system is modelled by a system of delay differential equations, which includes delay terms associated with the laser cavity and feedback loop. We make use of specialised path continuation software for delay differential equations to analyse the regime of short feedback delays. Specifically, we consider how the dynamics and bifurcations depend on the pump current of the laser, the feedback strength, and the feedback delay time. We show that an important role is played by resonances between the mode-locking frequencies and the feedback delay time. We find feedback-induced harmonic mode locking and show that a mismatch between the fundamental frequency of the laser and that of the feedback cavity can lead to multi-pulse or quasiperiodic dynamics. The quasiperiodic dynamics exhibit a slow modulation, on the time scale of the gain recovery rate, which results from a beating with the frequency introduced in the associated torus bifurcations and leads to gain competition between multiple pulse trains within the laser cavity. Our results also have implications for the case of large feedback delay times, where a complete bifurcation analysis is not practical. Namely, for increasing delay, there is an ever-increasing degree of multistability between mode-locked solutions due to the frequency pulling effect.

Robust stability analysis for Markovian jumping interval neural networks with discrete and distributed time-varying delays

International Nuclear Information System (INIS)

Balasubramaniam, P.; Lakshmanan, S.; Manivannan, A.

2012-01-01

Highlights: ► Robust stability analysis for Markovian jumping interval neural networks is considered. ► Both linear fractional and interval uncertainties are considered. ► A new LKF is constructed with triple integral terms. ► MATLAB LMI control toolbox is used to validate theoretical results. ► Numerical examples are given to illustrate the effectiveness of the proposed method. - Abstract: This paper investigates robust stability analysis for Markovian jumping interval neural networks with discrete and distributed time-varying delays. The parameter uncertainties are assumed to be bounded in given compact sets. The delay is assumed to be time-varying and belong to a given interval, which means that the lower and upper bounds of interval time-varying delays are available. Based on the new Lyapunov–Krasovskii functional (LKF), some inequality techniques and stochastic stability theory, new delay-dependent stability criteria have been obtained in terms of linear matrix inequalities (LMIs). Finally, two numerical examples are given to illustrate the less conservative and effectiveness of our theoretical results.

Daily physical activity in Finnish adolescents with long term illnesses or disabilities: psychosocial associations with participation in sports club

Directory of Open Access Journals (Sweden)

Kwok Ng

2016-09-01

Adolescents with LTID need encouragement to be active daily. One possible way to achieve this is through sports club participation. Implementing adaptive motivating techniques in sports clubs is especially important for girls in clubs. More research is needed on the associations of daily MVPA with different educational aspirations  for adolescents with LTID.

Assessing delay discounting in mice

OpenAIRE

Mitchell, Suzanne H.

2014-01-01

Delay discounting (also intertemporal choice or impulsive choice) is the process by which delayed outcomes, such as delayed food delivery, are valued less than the same outcomes delivered immediately or with a shorter delay. This process is of interest because many psychopathologies, including substance dependence, pathological gambling, attention deficit hyperactivity disorder and conduct disorder, are characterized by heightened levels of delay discounting. Some of these disorders are herit...

Modelling delays in pharmacokinetics

International Nuclear Information System (INIS)

Farooqi, Z.H.; Lambrecht, R.M.

1990-01-01

Linear system analysis has come to form the backbone of pharmacokinetics. Natural systems usually involve time delays, thus models incorporating them would be an order closer approximation to the real world compared to those that do not. Delays may be modelled in several ways. The approach considered in this study is to have a discrete-time delay dependent rate with the delay respresenting the duration between the entry of a drug into a compartment and its release in some form (may be as a metabolite) from the compartment. Such a delay may be because of one or more of several physiological reasons, like, formation of a reservoir, slow metabolism, or receptor binding. The mathematical structure this gives rise to is a system of delay-differential equations. Examples are given of simple one and two compartment systems with drugs like bumetanide, carbamazepine, and quinolone-caffeine interaction. In these examples generally a good fit is obtained and the suggested models form a good approximation. 21 refs., 6 figs

Multivalued stochastic delay differential equations and related ...

African Journals Online (AJOL)

We study the existence and uniqueness of a solution for the multivalued stochastic differential equation with delay (the multivalued term is of subdifferential type):. dX(t) + aφ (X(t))dt ∍ b(t,X(t), Y(t), Z(t)) dt. ⎨ +σ (t, X (t), Y (t), Z (t)) dW (t), t ∈ (s, T). X(t) = ξ (t - s), t ∈ [s - δ, s]. Specify that in this case the coefficients at time t ...

Self-critical perfectionism, daily stress, and disclosure of daily emotional events.

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Richardson, Clarissa M E; Rice, Kenneth G

2015-10-01

Although disclosure of stressful events can alleviate distress, self-critical perfectionism may pose an especially strong impediment to disclosure during stress, likely contributing to poorer psychological well-being. In the current study, after completing a measure of self-critical perfectionism (the Discrepancy subscale of the Almost Perfect Scale--Revised; Slaney, Rice, Mobley, Trippi, & Ashby, 2001), 396 undergraduates completed measures of stress and disclosure at the end of each day for 1 week. Consistent with hypotheses and previous research, multilevel modeling results indicated significant intraindividual coupling of daily stress and daily disclosure where disclosure was more likely when experiencing high stress than low stress. As hypothesized, Discrepancy moderated the relationship between daily stress and daily disclosure. Individuals higher in self-critical perfectionism (Discrepancy) were less likely to engage in disclosure under high stress, when disclosure is often most beneficial, than those with lower Discrepancy scores. These results have implications for understanding the role of stress and coping in the daily lives of self-critical perfectionists. (c) 2015 APA, all rights reserved).

Application of ray-traced tropospheric slant delays to geodetic VLBI analysis

Science.gov (United States)

Hofmeister, Armin; Böhm, Johannes

2017-08-01

National Aeronautics and Space Administration Goddard Space Flight Center (NASA GSFC) (Eriksson and MacMillan in http://lacerta.gsfc.nasa.gov/tropodelays, 2016) with respect to the analysis performances in terms of BLR results. If tropospheric gradient estimation is included in the analysis, 51.3% of the baselines benefit from the RADIATE ray-traced delays at sub-mm difference level. If no tropospheric gradients are estimated within the analysis, the RADIATE ray-traced delays deliver a better BLR at 63% of the baselines compared to the NASA GSFC ray-traced delays.

Trends in total and daily precipitation indices in japan from 1901 to 2000

OpenAIRE

Nagata, Rena; Zaiki, Masumi

2008-01-01

Long-term trends in seasonal precipitation amount and daily precipitation indices were investigated for spring, summer, autumn, and winter with a daily precipitation dataset for Japan from 1901 to 2000. Heavy precipitation in spring and summer has significantly increased along the west coast of Japan. Such changes in precipitation have resulted in the increased heavy precipitation intensity. For autumn and winter, total precipitation significantly decreased in the Kanto district and central J...

Impulsive stabilization and impulsive synchronization of discrete-time delayed neural networks.

Science.gov (United States)

Chen, Wu-Hua; Lu, Xiaomei; Zheng, Wei Xing

2015-04-01

This paper investigates the problems of impulsive stabilization and impulsive synchronization of discrete-time delayed neural networks (DDNNs). Two types of DDNNs with stabilizing impulses are studied. By introducing the time-varying Lyapunov functional to capture the dynamical characteristics of discrete-time impulsive delayed neural networks (DIDNNs) and by using a convex combination technique, new exponential stability criteria are derived in terms of linear matrix inequalities. The stability criteria for DIDNNs are independent of the size of time delay but rely on the lengths of impulsive intervals. With the newly obtained stability results, sufficient conditions on the existence of linear-state feedback impulsive controllers are derived. Moreover, a novel impulsive synchronization scheme for two identical DDNNs is proposed. The novel impulsive synchronization scheme allows synchronizing two identical DDNNs with unknown delays. Simulation results are given to validate the effectiveness of the proposed criteria of impulsive stabilization and impulsive synchronization of DDNNs. Finally, an application of the obtained impulsive synchronization result for two identical chaotic DDNNs to a secure communication scheme is presented.

Memory State Feedback RMPC for Multiple Time-Delayed Uncertain Linear Systems with Input Constraints

Directory of Open Access Journals (Sweden)

Wei-Wei Qin

2014-01-01

Full Text Available This paper focuses on the problem of asymptotic stabilization for a class of discrete-time multiple time-delayed uncertain linear systems with input constraints. Then, based on the predictive control principle of receding horizon optimization, a delayed state dependent quadratic function is considered for incorporating MPC problem formulation. By developing a memory state feedback controller, the information of the delayed plant states can be taken into full consideration. The MPC problem is formulated to minimize the upper bound of infinite horizon cost that satisfies the sufficient conditions. Then, based on the Lyapunov-Krasovskii function, a delay-dependent sufficient condition in terms of linear matrix inequality (LMI can be derived to design a robust MPC algorithm. Finally, the digital simulation results prove availability of the proposed method.

REASONS FOR PATIENT DELAYS & HEALTH SYSTEM DELAYS FOR TUBERCULOSIS IN SOUTH INDIA

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Kapil Goel

2011-12-01

Full Text Available Background: Globally, the burden of Tuberculosis is escalating. Early diagnosis and prompt initiation of tuberculosis treatment is essential for an effective tuberculosis control programme. Objectives: To study the self reported reasons for patient and health system (diagnosis & treatment delays in Tuberculosis patients. Methods: A community based cross sectional study was conducted among 98 new sputum positive TB cases aged > 15 years registered under RNTCP from Oct 2006 to June 2007 & receiving treatment under DOTS in Udupi taluk by interviewing them. Results: Total 98 patients were recruited and 68% were males. Out of 17 patients with patient delays, 82% felt that their symptoms were not severe, 71% felt that patient delay was due to lack of awareness and 71% did not take it seriously. Out of 86 patients with health system delays, 82.6% of patients mentioned that doctor has not advised for sputum examination, 76.7% of patients told that they first consulted a private doctor, 21% of them mentioned that doctor was unaware to diagnose TB. Conclusion: Symptoms not severe is the main reason for the patient delay and doctor didn’t advise for sputum examination is the main reason for health system delays.

Predictive Models of Duration of Ground Delay Programs in New York Area Airports

Science.gov (United States)

Kulkarni, Deepak

2011-01-01

Initially planned GDP duration often turns out to be an underestimate or an overestimate of the actual GDP duration. This, in turn, results in avoidable airborne or ground delays in the system. Therefore, better models of actual duration have the potential of reducing delays in the system. The overall objective of this study is to develop such models based on logs of GDPs. In a previous report, we described descriptive models of Ground Delay Programs. These models were defined in terms of initial planned duration and in terms of categorical variables. These descriptive models are good at characterizing the historical errors in planned GDP durations. This paper focuses on developing predictive models of GDP duration. Traffic Management Initiatives (TMI) are logged by Air Traffic Control facilities with The National Traffic Management Log (NTML) which is a single system for automated recoding, coordination, and distribution of relevant information about TMIs throughout the National Airspace System. (Brickman, 2004 Yuditsky, 2007) We use 2008-2009 GDP data from the NTML database for the study reported in this paper. NTML information about a GDP includes the initial specification, possibly one or more revisions, and the cancellation. In the next section, we describe general characteristics of Ground Delay Programs. In the third section, we develop models of actual duration. In the fourth section, we compare predictive performance of these models. The final section is a conclusion.

Incidence Probability of Delayed Health Consequences of the Chernobyl Accident

International Nuclear Information System (INIS)

Abdel-Ghani, A.H.; El-Naggar, A.M.; El-Kadi, A.A.

2000-01-01

During the first international Conference on the long -term consequences of the Chernobyl disaster in 1995 at Kiev, and also during the 1996 International Conference at Vienna, Summing up the consequences of the Chernobyl accident, the data regarding the delayed health consequences were mainly related to thyroid cancer, hereditary disorders, general morbidity, mortality and psychological disturbances. Contrary to expectations, the incidences of Leukemia and Soft Tissue tumors were similar to the spontaneous incident. The expected delayed effects, however, among the accident survivors, the liquidators and populations resident in contaminated areas would show higher incidence probability to Leukemia. These population groups have been continuously exposed to low level radiation both externally and internally. Application of the new ICRP concept of radiation-induced Detriment, and the Nominal Probability Coefficient for Cancer and hereditary effects for both workers and populations are used as the rationale to calculate the incidence probability of occurrence of delayed health effects of the Chernobyl accidents

Daily-life gait quality as predictor of falls in older people: A 1-year prospect cohort study

NARCIS (Netherlands)

Schooten, van K.S.; Pijnappels, M.A.G.M.; Rispens, S.M.; Elders, P.J.M.; Lips, P.; Daffertshofer, A.; Beek, P.J.; Dieen, van J.H.

2016-01-01

Falls can have devastating consequences for older people. We determined the relationship between the likelihood of fall incidents and daily-life behavior. We used wearable sensors to assess habitual physical activity and daily-life gait quality (in terms of e.g. stability, variability, smoothness

Delayed orgasm and anorgasmia.

Science.gov (United States)

Jenkins, Lawrence C; Mulhall, John P

2015-11-01

Delayed orgasm/anorgasmia defined as the persistent or recurrent difficulty, delay in, or absence of attaining orgasm after sufficient sexual stimulation, which causes personal distress. Delayed orgasm and anorgasmia are associated with significant sexual dissatisfaction. A focused medical history can shed light on the potential etiologies, which include medications, penile sensation loss, endocrinopathies, penile hyperstimulation, and psychological etiologies. Unfortunately, there are no excellent pharmacotherapies for delayed orgasm/anorgasmia, and treatment revolves largely around addressing potential causative factors and psychotherapy. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Variational Iteration Method for Volterra Functional Integrodifferential Equations with Vanishing Linear Delays

Directory of Open Access Journals (Sweden)

Ali Konuralp

2014-01-01

Full Text Available Application process of variational iteration method is presented in order to solve the Volterra functional integrodifferential equations which have multi terms and vanishing delays where the delay function θ(t vanishes inside the integral limits such that θ(t=qt for 0

Robust Weak Chimeras in Oscillator Networks with Delayed Linear and Quadratic Interactions

Science.gov (United States)

Bick, Christian; Sebek, Michael; Kiss, István Z.

2017-10-01

We present an approach to generate chimera dynamics (localized frequency synchrony) in oscillator networks with two populations of (at least) two elements using a general method based on a delayed interaction with linear and quadratic terms. The coupling design yields robust chimeras through a phase-model-based design of the delay and the ratio of linear and quadratic components of the interactions. We demonstrate the method in the Brusselator model and experiments with electrochemical oscillators. The technique opens the way to directly bridge chimera dynamics in phase models and real-world oscillator networks.

A semi-analytical approach for solving of nonlinear systems of functional differential equations with delay

Science.gov (United States)

Rebenda, Josef; Šmarda, Zdeněk

2017-07-01

In the paper, we propose a correct and efficient semi-analytical approach to solve initial value problem for systems of functional differential equations with delay. The idea is to combine the method of steps and differential transformation method (DTM). In the latter, formulas for proportional arguments and nonlinear terms are used. An example of using this technique for a system with constant and proportional delays is presented.

Long-term safety and efficacy of twice-daily aclidinium bromide in patients with COPD.

Science.gov (United States)

Gelb, Arthur F; Tashkin, Donald P; Make, Barry J; Zhong, Xiaoyun; Garcia Gil, Esther; Caracta, Cynthia

2013-12-01

Aclidinium is a novel, long-acting muscarinic antagonist indicated for maintenance treatment of COPD. In this 52-week, parallel-group, double-blind study, patients with moderate-to-severe COPD were randomized (1:1) to receive aclidinium twice-daily (BID) 200 μg or 400 μg via a novel, dry powder inhaler (Genuair(®)/Pressair(®)) [Registered trademarks of Almirall, SA, Barcelona, Spain for use within the European Union, Iceland, Norway, and Switzerland as Genuair(®) and within the United States as Pressair(®)]. Safety, the primary objective, was assessed via adverse events (AEs), clinical laboratory tests, vital signs, and 12-lead electrocardiograms. Efficacy was evaluated using spirometry, SGRQ, and rescue medication use. A total of 605 patients were randomized in the study. The percentage of patients reporting any treatment-emergent AE (TEAE) was comparable between groups; most TEAEs were mild or moderate. Anticholinergic TEAEs were reported by low percentages of patients in either treatment group (dry mouth: 200 μg, 1.3%; 400 μg, 2.7%; constipation: 200 μg, 2.9%; 400 μg, 1.7%). Cardiac TEAEs were also reported by a low percentage of patients (<2% for any event in any group) and did not appear to be dose dependent. There were no clinically relevant abnormalities in other safety outcomes. Both aclidinium 200 μg and 400 μg resulted in improvements from baseline to Week 52 in FEV1, with numerically greater increases observed with the higher dose. Clinically important improvements in SGRQ scores and a reduction in rescue medication use were observed throughout the study for both doses. Long-term treatment with aclidinium 200 μg or 400 μg BID was well tolerated, with sustained benefits in lung function and health status in patients with COPD throughout the 1-year study. Copyright © 2013 Elsevier Ltd. All rights reserved.

Relationships Among Nightly Sleep Quality, Daily Stress, and Daily Affect.

Science.gov (United States)

Blaxton, Jessica M; Bergeman, Cindy S; Whitehead, Brenda R; Braun, Marcia E; Payne, Jessic D

2017-05-01

We explored the prospective, microlevel relationship between nightly sleep quality (SQ) and the subsequent day's stress on positive (PA) and negative affect (NA) as well as the moderating relationships between nightly SQ, subsequent stress, and subsequent PA on NA. We investigated whether age moderated these relationships. We collected 56 days of sleep, stress, and affect data using daily diary questionnaires (N = 552). We used multilevel modeling to assess relationships at the between- and within-person levels. Daily increases in SQ and decreases in stress interacted to predict higher daily PA and lower daily NA. Better SQ in older adults enhanced the benefits of PA on the stress-NA relationship more during times of low stress, whereas better sleep in younger adults enhanced the benefits of PA more during times of high stress. Between-person effects were stronger predictors of well-being outcomes than within-person variability. The combination of good SQ and higher PA buffered the impact of stress on NA. The moderating impact of age suggests that sleep and stress play different roles across adulthood. Targeting intervention and prevention strategies to improve SQ and enhance PA could disrupt the detrimental relationship between daily stress and NA. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Effects of brief time delays on matching-to-sample abilities in capuchin monkeys (Sapajus spp.).

Science.gov (United States)

Truppa, Valentina; De Simone, Diego Antonio; Piano Mortari, Eva; De Lillo, Carlo

2014-09-01

Traditionally, studies of delayed matching-to-sample (DMTS) tasks in nonhuman species have focused on the assessment of the limits of the retrieval of information stored in short- and long-term memory systems. However, it is still unclear if visual recognition in these tasks is affected by very brief delay intervals, which are typically used to study rapidly decaying types of visual memory. This study aimed at evaluating if tufted capuchin monkeys' ability to recognise visual stimuli in a DMTS task is affected by (i) the disappearance of the sample stimulus and (ii) the introduction of delay intervals (0.5, 1.0, 2.0 and 3.0s) between the disappearance of the sample and the presentation of the comparison stimuli. The results demonstrated that the simple disappearance of the sample and the introduction of a delay of 0.5s did not affect capuchins' performance either in terms of accuracy or response time. A delay interval of 1.0s produced a significant increase in response time but still did not affect recognition accuracy. By contrast, delays of 2.0 and 3.0s determined a significant increase in response time and a reduction in recognition accuracy. These findings indicate the existence in capuchin monkeys of processes enabling a very accurate retention of stimulus features within time frames comparable to those reported for humans' sensory memory (0.5-1.0s). The extent to which such processes can be considered analogous to the sensory memory processes observed in human visual cognition is discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

Exponential synchronization of chaotic Lur'e systems with time-varying delay via sampled-data control

International Nuclear Information System (INIS)

Rakkiyappan, R.; Sivasamy, R.; Lakshmanan, S.

2014-01-01

In this paper, we study the exponential synchronization of chaotic Lur'e systems with time-varying delays via sampled-data control by using sector nonlinearties. In order to make full use of information about sampling intervals and interval time-varying delays, new Lyapunov—Krasovskii functionals with triple integral terms are introduced. Based on the convex combination technique, two kinds of synchronization criteria are derived in terms of linear matrix inequalities, which can be efficiently solved via standard numerical software. Finally, three numerical examples are provided to demonstrate the less conservatism and effectiveness of the proposed results

The Effect of Concurrent Semantic Categorization on Delayed Serial Recall

Science.gov (United States)

Acheson, Daniel J.; MacDonald, Maryellen C.; Postle, Bradley R.

2011-01-01

The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Participants engaged in 2 picture-judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content…

Working Memory Encoding Delays Top-Down Attention to Visual Cortex

Science.gov (United States)

Scalf, Paige E.; Dux, Paul E.; Marois, Rene

2011-01-01

The encoding of information from one event into working memory can delay high-level, central decision-making processes for subsequent events [e.g., Jolicoeur, P., & Dell'Acqua, R. The demonstration of short-term consolidation. "Cognitive Psychology, 36", 138-202, 1998, doi:10.1006/cogp.1998.0684]. Working memory, however, is also believed to…

High-explosive-driven delay line pulse generator

International Nuclear Information System (INIS)

Shearer, J.W.

1982-01-01

The inclusion of a delay line circuit into the design of a high-explosive-driven generator shortens the time constant of the output pulse. After a brief review of generator concepts and previously described pulse-shortening methods, a geometry is presented which incorporates delay line circuit techcniques into a coil generator. The circuit constants are adjusted to match the velocity of the generated electromagnetic wave to the detonation velocity of the high explosive. The proposed generator can be modeled by adding a variable inductance term to the telegrapher's equation. A particular solution of this equation is useful for exploring the operational parameters of the generator. The duration of the electromagnetic pulse equals the radial expansion time of the high-explosive-driven armature until it strikes the coil. Because the impedance of the generator is a constant, the current multiplication factor is limited only by nonlinear effects such as voltage breakdown, diffusion, and compression at high energies

A frequency-domain method for solving linear time delay systems with constant coefficients

Science.gov (United States)

Jin, Mengshi; Chen, Wei; Song, Hanwen; Xu, Jian

2018-03-01

In an active control system, time delay will occur due to processes such as signal acquisition and transmission, calculation, and actuation. Time delay systems are usually described by delay differential equations (DDEs). Since it is hard to obtain an analytical solution to a DDE, numerical solution is of necessity. This paper presents a frequency-domain method that uses a truncated transfer function to solve a class of DDEs. The theoretical transfer function is the sum of infinite items expressed in terms of poles and residues. The basic idea is to select the dominant poles and residues to truncate the transfer function, thus ensuring the validity of the solution while improving the efficiency of calculation. Meanwhile, the guideline of selecting these poles and residues is provided. Numerical simulations of both stable and unstable delayed systems are given to verify the proposed method, and the results are presented and analysed in detail.

[Risk of deaths from cardiovascular diseases in Polish urban population associated with changes in maximal daily temperature].

Science.gov (United States)

Rabczenko, Daniel; Wojtyniak, Bogdan; Kuchcik, Magdalena; Seroka, Wojciech

2009-01-01

The paper presents results of analysis of short-term effect of changes in maximal daily temperature on daily mortality from cardiovascular diseases in warm season in years 1999-2006. Analysis was carried out in six large Polish cities--Katowice, Kraków, Łódź, Poznań, Warszawa and Wrocław. Generalized additive models were used in the analysis. Potential confounding factors--long term changes of mortality, day of week and other meteorological factors (atmospheric pressure, humidity, mean wind speed) were taken into account during model building process. Analysis was done for two age groups--0-69 and 70 years and older. Significant, positive association between daily maximal temperature and risk of death from cardiovascular diseases was found only in older age group.

Long-term effects of radiation

International Nuclear Information System (INIS)

Smith, J.; Smith, T.

1981-01-01

It is pointed out that sources of long-term damage from radiation are two-fold. People who have been exposed to doses of radiation from initial early fallout but have recovered from the acute effects may still suffer long-term damage from their exposure. Those who have not been exposed to early fallout may be exposed to delayed fallout, the hazards from which are almost exclusively from ingesting strontium, caesium and carbon isotopes present in food; the damage caused is relatively unimportant compared with that caused by the brief doses from initial radiation and early fallout. A brief discussion is presented of the distribution of delayed long-lived isotope fallout, and an outline is sketched of late biological effects, such as malignant disease, cataracts, retarded development, infertility and genetic effects. (U.K.)

Oral Health Characteristics and Dental Rehabilitation of Children with Global Developmental Delay

Directory of Open Access Journals (Sweden)

Saurabh Kumar

2017-01-01

Full Text Available Global developmental delay (GDD is a chronic neurological disturbance which includes defects in one or more developmental domains. The developmental domain can be motor, cognitive, daily activities, speech or language, and social or personal development. The etiology for GDD can be prenatal, perinatal, or postnatal. It can be diagnosed early in childhood as the delay or absence of one or more developmental milestones. Hence the role of pedodontist and pediatricians becomes more crucial in identifying this condition. The diagnosis of GDD requires a detailed history including family history and environmental risk factors followed by physical and neurological examinations. Investigations for GDD include diagnostic laboratory tests, brain imaging, and other evidence-based evaluations. GDD affects multiple developmental domains that not only have direct bearing on maintenance of oral health, but also require additional behavior management techniques to deliver optimal dental care. This paper describes two different spectra of children with GDD. Since the severity of GDD can vary, this paper also discusses the different behavior management techniques that were applied to provide dental treatment in such children.

Oral Health Characteristics and Dental Rehabilitation of Children with Global Developmental Delay.

Science.gov (United States)

Kumar, Saurabh; Pai, Deepika; Saran, Runki

2017-01-01

Global developmental delay (GDD) is a chronic neurological disturbance which includes defects in one or more developmental domains. The developmental domain can be motor, cognitive, daily activities, speech or language, and social or personal development. The etiology for GDD can be prenatal, perinatal, or postnatal. It can be diagnosed early in childhood as the delay or absence of one or more developmental milestones. Hence the role of pedodontist and pediatricians becomes more crucial in identifying this condition. The diagnosis of GDD requires a detailed history including family history and environmental risk factors followed by physical and neurological examinations. Investigations for GDD include diagnostic laboratory tests, brain imaging, and other evidence-based evaluations. GDD affects multiple developmental domains that not only have direct bearing on maintenance of oral health, but also require additional behavior management techniques to deliver optimal dental care. This paper describes two different spectra of children with GDD. Since the severity of GDD can vary, this paper also discusses the different behavior management techniques that were applied to provide dental treatment in such children.

Earth system commitments due to delayed mitigation

International Nuclear Information System (INIS)

Pfister, Patrik L; Stocker, Thomas F

2016-01-01

As long as global CO 2 emissions continue to increase annually, long-term committed Earth system changes grow much faster than current observations. A novel metric linking this future growth to policy decisions today is the mitigation delay sensitivity (MDS), but MDS estimates for Earth system variables other than peak temperature (ΔT max ) are missing. Using an Earth System Model of Intermediate Complexity, we show that the current emission increase rate causes a ΔT max increase roughly 3–7.5 times as fast as observed warming, and a millenial steric sea level rise (SSLR) 7–25 times as fast as observed SSLR, depending on the achievable rate of emission reductions after the peak of emissions. These ranges are only slightly affected by the uncertainty range in equilibrium climate sensitivity, which is included in the above values. The extent of ocean acidification at the end of the century is also strongly dependent on the starting time and rate of emission reductions. The preservable surface ocean area with sufficient aragonite supersaturation for coral reef growth is diminished globally at an MDS of roughly 25%–80% per decade. A near-complete loss of this area becomes unavoidable if mitigation is delayed for a few years to decades. Also with respect to aragonite, 12%–18% of the Southern Ocean surface become undersaturated per decade, if emission reductions are delayed beyond 2015–2040. We conclude that the consequences of delaying global emission reductions are much better captured if the MDS of relevant Earth system variables is communicated in addition to current trends and total projected future changes. (letter)

Infant Imitation after a 1-Week Delay: Long-Term Memory for Novel Acts and Multiple Stimuli.

Science.gov (United States)

Meltzoff, Andrew N.

1988-01-01

Investigated deferred imitation ability for six actions in 14-month-old infants. After a week's delay, infants were tested on their ability to imitate the actions.Those who had been exposed to modeling produced significantly higher instances of the target actions. (SKC)

Three-level system driven by delayed pulses of finite duration

International Nuclear Information System (INIS)

Ishkhanyan, Artur; Suominen, Kalle-Antti

2002-01-01

We find the exact solution to the three-state problem for a class of intuitive and counterintuitive sequences of delayed pulses of finite duration in terms of the Clausen's generalized hypergeometric function, which reduces to simple analytic expressions, involving elementary functions only, for final occupation probabilities. These analytic results show that the sequence of delayed pulses, independently of the pulse order and applied detunings, can completely remove the population from the initially populated state (thus creating a quantum superposition of two other involved states). This conclusion extends the original result of Vitanov and Stenholm [Phys. Rev. A 55, 648 (1997)], to the case of nonzero two-photon detuning and more general pulse shapes

Cooperative Content Distribution over Wireless Networks for Energy and Delay Minimization

KAUST Repository

Atat, Rachad

2012-06-01

Content distribution with mobile-to-mobile cooperation is studied. Data is sent to mobile terminals on a long range link then the terminals exchange the content using an appropriate short range wireless technology. Unicasting and multicasting are investigated, both on the long range and short range links. Energy minimization is formulated as an optimization problem for each scenario, and the optimal solutions are determined in closed form. Moreover, the schemes are applied in public safety vehicular networks, where Long Term Evolution (LTE) network is used for the long range link, while IEEE 802.11 p is considered for inter-vehicle collaboration on the short range links. Finally, relay-based multicasting is applied in high speed trains for energy and delay minimization. Results show that cooperative schemes outperform non-cooperative ones and other previous related work in terms of energy and delay savings. Furthermore, practical implementation aspects of the proposed methods are also discussed.

Combining Radar and Daily Precipitation Data to Estimate Meaningful Sub-daily Precipitation Extremes

Science.gov (United States)

Pegram, G. G. S.; Bardossy, A.

2016-12-01

Short duration extreme rainfalls are important for design. The purpose of this presentation is not to improve the day by day estimation of precipitation, but to obtain reasonable statistics for the subdaily extremes at gauge locations. We are interested specifically in daily and sub-daily extreme values of precipitation at gauge locations. We do not employ the common procedure of using time series of control station to determine the missing data values in a target. We are interested in individual rare events, not sequences. The idea is to use radar to disaggregate daily totals to sub-daily amounts. In South Arica, an S-band radar operated relatively continuously at Bethlehem from 1998 to 2003, whose scan at 1.5 km above ground [CAPPI] overlapped a dense (10 km spacing) set of 45 pluviometers recording in the same 6-year period. Using this valuable set of data, we are only interested in rare extremes, therefore small to medium values of rainfall depth were neglected, leaving 12 days of ranked daily maxima in each set per year, whose sum typically comprised about 50% of each annual rainfall total. The method presented here uses radar for disaggregating daily gauge totals in subdaily intervals down to 15 minutes in order to extract the maxima of sub-hourly through to daily rainfall at each of 37 selected radar pixels [1 km square in plan] which contained one of the 45 pluviometers not masked out by the radar foot-print. The pluviometer data were aggregated to daily totals, to act as if they were daily read gauges; their only other task was to help in the cross-validation exercise. The extrema were obtained as quantiles by ordering the 12 daily maxima of each interval per year. The unusual and novel goal was not to obtain the reproduction of the precipitation matching in space and time, but to obtain frequency distributions of the gauge and radar extremes, by matching their ranks, which we found to be stable and meaningful in cross-validation tests. We provide and

An experimental field study of delayed density dependence in natural populations of Aedes albopictus.

Directory of Open Access Journals (Sweden)

Rachael K Walsh

Full Text Available Aedes albopictus, a species known to transmit dengue and chikungunya viruses, is primarily a container-inhabiting mosquito. The potential for pathogen transmission by Ae. albopictus has increased our need to understand its ecology and population dynamics. Two parameters that we know little about are the impact of direct density-dependence and delayed density-dependence in the larval stage. The present study uses a manipulative experimental design, under field conditions, to understand the impact of delayed density dependence in a natural population of Ae. albopictus in Raleigh, North Carolina. Twenty liter buckets, divided in half prior to experimentation, placed in the field accumulated rainwater and detritus, providing oviposition and larval production sites for natural populations of Ae. albopictus. Two treatments, a larvae present and larvae absent treatment, were produced in each bucket. After five weeks all larvae were removed from both treatments and the buckets were covered with fine mesh cloth. Equal numbers of first instars were added to both treatments in every bucket. Pupae were collected daily and adults were frozen as they emerged. We found a significant impact of delayed density-dependence on larval survival, development time and adult body size in containers with high larval densities. Our results indicate that delayed density-dependence will have negative impacts on the mosquito population when larval densities are high enough to deplete accessible nutrients faster than the rate of natural food accumulation.

Persistent Language Delay Versus Late Language Emergence in Children With Early Cochlear Implantation

Science.gov (United States)

Nicholas, Johanna; Tobey, Emily; Davidson, Lisa

2016-01-01

Purpose The purpose of the present investigation is to differentiate children using cochlear implants (CIs) who did or did not achieve age-appropriate language scores by midelementary grades and to identify risk factors for persistent language delay following early cochlear implantation. Materials and Method Children receiving unilateral CIs at young ages (12–38 months) were tested longitudinally and classified with normal language emergence (n = 19), late language emergence (n = 22), or persistent language delay (n = 19) on the basis of their test scores at 4.5 and 10.5 years of age. Relative effects of demographic, audiological, linguistic, and academic characteristics on language emergence were determined. Results Age at CI was associated with normal language emergence but did not differentiate late emergence from persistent delay. Children with persistent delay were more likely to use left-ear implants and older speech processor technology. They experienced higher aided thresholds and lower speech perception scores. Persistent delay was foreshadowed by low morphosyntactic and phonological diversity in preschool. Logistic regression analysis predicted normal language emergence with 84% accuracy and persistent language delay with 74% accuracy. Conclusion CI characteristics had a strong effect on persistent versus resolving language delay, suggesting that right-ear (or bilateral) devices, technology upgrades, and improved audibility may positively influence long-term language outcomes. PMID:26501740

American Dream Delayed

DEFF Research Database (Denmark)

Khorunzhina, Natalia; Miller, Robert A.

This paper investigates the delay in homeownership and a subsequent reduction in homeownership rate observed over the past decades. We focus on the delay in giving birth to children and increased labor market participation as contributing factors to homeownership dynamics for prime-age female hou...

Delayed Orgasm and Anorgasmia

OpenAIRE

Jenkins, Lawrence C.; Mulhall, John P.

2015-01-01

Delayed orgasm/anorgasmia defined as the persistent or recurrent difficulty, delay in, or absence of attaining orgasm after sufficient sexual stimulation, which causes personal distress. Delayed orgasm and anorgasmia are associated with significant sexual dissatisfaction. A focused medical history can shed light on the potential etiologies; which include: medications, penile sensation loss, endocrinopathies, penile hyperstimulation and psychological etiologies, amongst others. Unfortunately, ...

Delayed-release oral suspension of omeprazole for the treatment of erosive esophagitis and gastroesophageal reflux disease in pediatric patients: a review

Directory of Open Access Journals (Sweden)

Alice Monzani

2010-03-01

Full Text Available Alice Monzani, Giuseppina Oderda1Department of Pediatrics, Università del Piemonte Orientale, Novara, ItalyAbstract: Omeprazole is a proton-pump inhibitor indicated for gastroesophageal reflux disease and erosive esophagitis treatment in children. The aim of this review was to evaluate the efficacy of delayed-release oral suspension of omeprazole in childhood esophagitis, in terms of symptom relief, reduction in reflux index and/or intragastric acidity, and endoscopic and/or histological healing. We systematically searched PubMed, Cochrane and EMBASE (1990 to 2009 and identified 59 potentially relevant articles, but only 12 articles were suitable to be included in our analysis. All the studies evaluated symptom relief and reported a median relief rate of 80.4% (range 35%–100%. Five studies reported a significant reduction of the esophageal reflux index within normal limits (<7% in all children, and 4 studies a significant reduction of intra-gastric acidity. The endoscopic healing rate, reported by 9 studies, was 84% after 8-week treatment and 95% after 12-week treatment, the latter being significantly higher than the histological healing rate (49%. In conclusion, omeprazole given at a dose ranging from 0.3 to 3.5 mg/kg once daily (median 1 mg/kg once daily for at least 12 weeks is highly effective in childhood esophagitis.Keywords: proton pump inhibitors, children, ranitidine, H2-blockers

Predator-prey-subsidy population dynamics on stepping-stone domains with dispersal delays.

Science.gov (United States)

Eide, Ragna M; Krause, Andrew L; Fadai, Nabil T; Van Gorder, Robert A

2018-08-14

We examine the role of the travel time of a predator along a spatial network on predator-prey population interactions, where the predator is able to partially or fully sustain itself on a resource subsidy. The impact of access to food resources on the stability and behaviour of the predator-prey-subsidy system is investigated, with a primary focus on how incorporating travel time changes the dynamics. The population interactions are modelled by a system of delay differential equations, where travel time is incorporated as discrete delay in the network diffusion term in order to model time taken to migrate between spatial regions. The model is motivated by the Arctic ecosystem, where the Arctic fox consumes both hunted lemming and scavenged seal carcass. The fox travels out on sea ice, in addition to quadrennially migrating over substantial distances. We model the spatial predator-prey-subsidy dynamics through a "stepping-stone" approach. We find that a temporal delay alone does not push species into extinction, but rather may stabilize or destabilize coexistence equilibria. We are able to show that delay can stabilize quasi-periodic or chaotic dynamics, and conclude that the incorporation of dispersal delay has a regularizing effect on dynamics, suggesting that dispersal delay can be proposed as a solution to the paradox of enrichment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Derivation and computation of discrete-delay and continuous-delay SDEs in mathematical biology.

Science.gov (United States)

Allen, Edward J

2014-06-01

Stochastic versions of several discrete-delay and continuous-delay differential equations, useful in mathematical biology, are derived from basic principles carefully taking into account the demographic, environmental, or physiological randomness in the dynamic processes. In particular, stochastic delay differential equation (SDDE) models are derived and studied for Nicholson's blowflies equation, Hutchinson's equation, an SIS epidemic model with delay, bacteria/phage dynamics, and glucose/insulin levels. Computational methods for approximating the SDDE models are described. Comparisons between computational solutions of the SDDEs and independently formulated Monte Carlo calculations support the accuracy of the derivations and of the computational methods.

Attosecond Delays in Molecular Photoionization.

Science.gov (United States)

Huppert, Martin; Jordan, Inga; Baykusheva, Denitsa; von Conta, Aaron; Wörner, Hans Jakob

2016-08-26

We report measurements of energy-dependent photoionization delays between the two outermost valence shells of N_{2}O and H_{2}O. The combination of single-shot signal referencing with the use of different metal foils to filter the attosecond pulse train enables us to extract delays from congested spectra. Remarkably large delays up to 160 as are observed in N_{2}O, whereas the delays in H_{2}O are all smaller than 50 as in the photon-energy range of 20-40 eV. These results are interpreted by developing a theory of molecular photoionization delays. The long delays measured in N_{2}O are shown to reflect the population of molecular shape resonances that trap the photoelectron for a duration of up to ∼110 as. The unstructured continua of H_{2}O result in much smaller delays at the same photon energies. Our experimental and theoretical methods make the study of molecular attosecond photoionization dynamics accessible.

8-group relative delayed neutron yields for epithermal neutron induced fission of 235U and 239Pu

International Nuclear Information System (INIS)

Piksaikin, V.M.; Kazakov, L.E.; Isaev, S.G.; Korolev, G.G.; Roshchenko, V.A.; Tertychnyj, R.G

2002-01-01

An 8-group representation of relative delayed neutron yields was obtained for epithermal neutron induced fission of 235 U and 239 Pu. These data were compared with ENDF/B-VI data in terms of the average half- life of the delayed neutron precursors and on the basis of the dependence of reactivity on the asymptotic period. (author)

Fast realization of nonrecursive digital filters with limits on signal delay

Science.gov (United States)

Titov, M. A.; Bondarenko, N. N.

1983-07-01

Attention is given to the problem of achieving a fast realization of nonrecursive digital filters with the aim of reducing signal delay. It is shown that a realization wherein the impulse characteristic of the filter is divided into blocks satisfies the delay requirements and is almost as economical in terms of the number of multiplications as conventional fast convolution. In addition, the block method leads to a reduction in the needed size of the memory and in the number of additions; the short-convolution procedure is substantially simplified. Finally, the block method facilitates the paralleling of computations owing to the simple transfers between subfilters.

Trauma patients who present in a delayed fashion: a unique and challenging population.

Science.gov (United States)

Kao, Mary J; Nunez, Hector; Monaghan, Sean F; Heffernan, Daithi S; Adams, Charles A; Lueckel, Stephanie N; Stephen, Andrew H

2017-02-01

A proportion of trauma patients present for evaluation in a delayed fashion after injury, likely due to a variety of medical and nonmedical reasons. There has been little investigation into the characteristics and outcomes of trauma patients who present delayed. We hypothesize that trauma patients who present in a delayed fashion are a unique population at risk of increased trauma-related complications. This was a retrospective review from 2010-2015 at a Level I trauma center. Patients were termed delayed if they presented >24 hours after injury. Patients admitted within 24 hours of their injury were the comparison group. Charts were reviewed for demographics, mechanism, comorbidities, complications and outcomes. A subgroup analysis was done on patients who suffered falls. During the 5-y period, 11,705 patients were admitted. A total of 588 patients (5%) presented >24 h after their injury. Patients in the delayed group were older (65 versus 55 y, P fashion have unique characteristics and are more likely to suffer negative outcomes including substance withdrawal. Future goals will include exploring strategies for early intervention, such as automatic withdrawal monitoring and social work referral for all patients who present in a delayed fashion. Copyright © 2016 Elsevier Inc. All rights reserved.

Impact of long-term HPN on daily life in adults.

NARCIS (Netherlands)

Persoon, A.; Huisman-de Waal, G.J.; Naber, A.H.J.; Schoonhoven, L.; Tas, T.; Sauerwein, H.P.; Achterberg, T. van

2005-01-01

BACKGROUND AND AIMS: Home parenteral nutrition (HPN) is a therapy that changes life radically and often means lifelong dependence on parenteral feeding. The aim of this study was to gain insight into problems experienced by adult patients who were dependent on long-term HPN. METHODS: A survey was

Springs-neaps cycles in daily total seabed light: Daylength-induced changes

Science.gov (United States)

Roberts, E. M.; Bowers, D. G.; Davies, A. J.

2014-04-01

In shallow, tidal seas, daily total seabed light is determined largely by the interaction of the solar elevation cycle, the tidal cycle in water depth, and any temporal variability in turbidity. Since tidal range, times of low water, and often turbidity vary in regular ways over the springs-neaps cycle, daily total seabed light exhibits cycles of the same periodicity. Corresponding cycles are likely to be induced in the daily total primary production of benthic algae and plants, particularly those light-limited specimens occupying the lower reaches of a sub-tidal population. Consequently, this effect is an important control on the growth patterns, depth distribution and survival of, for example, macroalgal forests and seagrass meadows. Seasonal changes in daylength exert an important additional control on these cycles, as they alter the fraction of the tidal and turbidity cycles occurring within daylight hours. Bowers et al. (1997) modelled this phenomenon numerically and predicted that for a site with low water at about midday and midnight at neaps tides, 6 am and 6 pm at springs, daily total seabed light peaks at neaps in winter, but the ‘sense' of the cycle ‘switches' so that it peaks at springs in summer - the longer daylength permits the morning and evening low water springs to contribute substantially to the daily total. Observations for such a site in North Wales (UK), presented in this paper, show that no such ‘switch' occurs, and neaps tides host the largest daily totals throughout the year. The predicted ‘switch' is not observed because turbidity increases generally at spring tides, and specifically at low water springs, both of which were not accounted for in the model. Observations at a second site in Brittany (France), diametrically opposite in terms of the times of low water at neaps and at springs, indicate a peak at springs throughout the year. Analytical tools are developed to calculate the percentage of daily total sea surface irradiance

Intraindividual change and variability in daily stress processes: Findings from two measurement-burst diary studies

Science.gov (United States)

Sliwinski, Martin J.; Almeida, David M.; Smyth, Joshua; Stawski, Robert S.

2010-01-01

There is little longitudinal information on aging-related changes in emotional responses to negative events. The present manuscript examined intraindividual change and variability in the within-person coupling of daily stress and negative affect (NA) using data from two-measurement burst daily diary studies. Three main findings emerged. First, average reactivity to daily stress increased longitudinally, and this increase was evident across most the adult lifespan. Second, individual differences in emotional reactivity to daily stress exhibited long-term temporal stability, but this stability was greatest in midlife and decreased in old age. And third, reactivity to daily stress varied reliably within-persons (across-time), with individual exhibiting higher levels of reactivity during times when reporting high levels of global subject stress in previous month. Taken together, the present results emphasize the importance of modeling dynamic psychosocial and aging processes that operate across different time scales for understanding age-related changes in daily stress processes. PMID:20025399

Large Deviations for Two-Time-Scale Diffusions, with Delays

International Nuclear Information System (INIS)

Kushner, Harold J.

2010-01-01

We consider the problem of large deviations for a two-time-scale reflected diffusion process, possibly with delays in the dynamical terms. The Dupuis-Ellis weak convergence approach is used. It is perhaps the most intuitive and simplest for the problems of concern. The results have applications to the problem of approximating optimal controls for two-time-scale systems via use of the averaged equation.

Stabilization of the Wave Equation with Boundary Time-Varying Delay

Directory of Open Access Journals (Sweden)

Hao Li

2014-01-01

Full Text Available We study the stabilization of the wave equation with variable coefficients in a bounded domain and a time-varying delay term in the time-varying, weakly nonlinear boundary feedbacks. By the Riemannian geometry methods and a suitable assumption of nonlinearity, we obtain the uniform decay of the energy of the closed loop system.

The social cost of congestion games by imposing variable delays

Directory of Open Access Journals (Sweden)

Josep Díaz

2017-12-01

Full Text Available In this study, we describe a new coordination mechanism for non-atomic congestion games that leads to a (selfish social cost which is arbitrarily close to the non-selfish optimal. This mechanism incurs no additional cost, in contrast to tolls that typically differ from the social cost as expressed in terms of delays.

Gadobenate dimeglumine-enhanced MR of VX2 carcinoma in rabbit liver: usefulness of the delayed phase imaging and optimal pulse sequence

Energy Technology Data Exchange (ETDEWEB)

Cho, Seung Il; Lee, Jeong Min; Kim, Young Kon; Kim, Chong Soo [College of Medicine, Chonbuk National Univ., Chonju (Korea, Republic of)

2002-07-01

To assess the diagnostic value of delayed imaging using gadobenate dimeglumine (MultiHance) and to determine the optimal pulse sequence for the detection of VX2 carcinoma lesions in the rabbit. Twelve VX2 carcinomas implanted in the livers of eleven New Zealand rabbits were studied. All patients underwent an MR protocal consisting of precontrast T2-and T1-weighted sequences, followed by repetition of the T1-weighted sequence at 0 to 30 (arterial phase). 31-60 (portal phase), and 40 minutes (delayed phase) after the intravenous administration of 0.1 mmol/kg of gadobenate dimeglumine. The signal-to-noise ratio (SNR) of the liver and VX2 tumor, and the lesion-to-liver contrast-to-noise ratio (CNR) of precontrast and postcontrast MR images were quantitatively analyzed, and two experienced radiologists evaluated image quality in terms of lesion conspicuity, artifact, mass delineation, and vascular anatomy. Liver SNR was significantly higher at delayed imaging than at precontrast, arterial, and portal imaging (p<0.05), while lesion SNR was significantly higher at delayed imaging than at precontrast imaging (p<0.05). Lesion CNR was higher at delayed imaging than at precontrast and portal phase imaging (p<0.05), but there was no difference between arterial and delayed imaging. The latter provided better mass delineation than precontrast, arterial and portal phase imaging (p<0.05). While in terms of lesion conspicuity and vascular anatomy, the delayed phase was better than the arterial phase (p<0.05) but similar to the precontrast and portal phase. During the delayed phase, the gradient-echo sequence showed better results than the spin-echo in terms of liver SNR, and lesion SNR and CNR (p<0.05). Because it provides better lesion conspicuity and mass delineation by improving liver SNR and lesion-to-liver CNR, the addition of the delayed phase to a dynamic MRI sequence after gadobenate dimeglumine adminstration facilitates lesion detection. For delayed-phase imaging, the

Gadobenate dimeglumine-enhanced MR of VX2 carcinoma in rabbit liver: usefulness of the delayed phase imaging and optimal pulse sequence

International Nuclear Information System (INIS)

Cho, Seung Il; Lee, Jeong Min; Kim, Young Kon; Kim, Chong Soo

2002-01-01

To assess the diagnostic value of delayed imaging using gadobenate dimeglumine (MultiHance) and to determine the optimal pulse sequence for the detection of VX2 carcinoma lesions in the rabbit. Twelve VX2 carcinomas implanted in the livers of eleven New Zealand rabbits were studied. All patients underwent an MR protocal consisting of precontrast T2-and T1-weighted sequences, followed by repetition of the T1-weighted sequence at 0 to 30 (arterial phase). 31-60 (portal phase), and 40 minutes (delayed phase) after the intravenous administration of 0.1 mmol/kg of gadobenate dimeglumine. The signal-to-noise ratio (SNR) of the liver and VX2 tumor, and the lesion-to-liver contrast-to-noise ratio (CNR) of precontrast and postcontrast MR images were quantitatively analyzed, and two experienced radiologists evaluated image quality in terms of lesion conspicuity, artifact, mass delineation, and vascular anatomy. Liver SNR was significantly higher at delayed imaging than at precontrast, arterial, and portal imaging (p<0.05), while lesion SNR was significantly higher at delayed imaging than at precontrast imaging (p<0.05). Lesion CNR was higher at delayed imaging than at precontrast and portal phase imaging (p<0.05), but there was no difference between arterial and delayed imaging. The latter provided better mass delineation than precontrast, arterial and portal phase imaging (p<0.05). While in terms of lesion conspicuity and vascular anatomy, the delayed phase was better than the arterial phase (p<0.05) but similar to the precontrast and portal phase. During the delayed phase, the gradient-echo sequence showed better results than the spin-echo in terms of liver SNR, and lesion SNR and CNR (p<0.05). Because it provides better lesion conspicuity and mass delineation by improving liver SNR and lesion-to-liver CNR, the addition of the delayed phase to a dynamic MRI sequence after gadobenate dimeglumine adminstration facilitates lesion detection. For delayed-phase imaging, the

Enhancing endogenous stem cells in the newborn via delayed umbilical cord clamping

Directory of Open Access Journals (Sweden)

Christopher Lawton

2015-01-01

Full Text Available There is currently no consensus among clinicians and scientists over the appropriate or optimal timing for umbilical cord clamping. However, many clinical studies have suggested that delayed cord clamping is associated with various neonatal benefits including increased blood volume, reduced need for blood transfusion, increased cerebral oxygenation in pre-term infants, and decreased frequency of iron deficiency anemia in term infants. Human umbilical cord blood contains significant amounts of stem and progenitor cells and is currently used in the treatment of several life-threatening diseases. We propose that delayed cord clamping be encouraged as it enhances blood flow from the placenta to the neonate, which is accompanied by an increase supply of valuable stem and progenitor cells, as well as may improve blood oxygenation and increase blood volume, altogether reducing the infant′s susceptibility to both neonatal and age-related diseases.

Wheel-running activity modulates circadian organization and the daily rhythm of eating behavior

Science.gov (United States)

Pendergast, Julie S.; Branecky, Katrina L.; Huang, Roya; Niswender, Kevin D.; Yamazaki, Shin

2014-01-01

Consumption of high-fat diet acutely alters the daily rhythm of eating behavior and circadian organization (the phase relationship between oscillators in central and peripheral tissues) in mice. Voluntary wheel-running activity counteracts the obesogenic effects of high-fat diet and also modulates circadian rhythms in mice. In this study, we sought to determine whether voluntary wheel-running activity could prevent the proximate effects of high-fat diet consumption on circadian organization and behavioral rhythms in mice. Mice were housed with locked or freely rotating running wheels and fed chow or high-fat diet for 1 week and rhythms of locomotor activity, eating behavior, and molecular timekeeping (PERIOD2::LUCIFERASE luminescence rhythms) in ex vivo tissues were measured. Wheel-running activity delayed the phase of the liver rhythm by 4 h in both chow- and high-fat diet-fed mice. The delayed liver phase was specific to wheel-running activity since an enriched environment without the running wheel did not alter the phase of the liver rhythm. In addition, wheel-running activity modulated the effect of high-fat diet consumption on the daily rhythm of eating behavior. While high-fat diet consumption caused eating events to be more evenly dispersed across the 24 h-day in both locked-wheel and wheel-running mice, the effect of high-fat diet was much less pronounced in wheel-running mice. Together these data demonstrate that wheel-running activity is a salient factor that modulates liver phase and eating behavior rhythms in both chow- and high-fat-diet fed mice. Wheel-running activity in mice is both a source of exercise and a self-motivating, rewarding behavior. Understanding the putative reward-related mechanisms whereby wheel-running activity alters circadian rhythms could have implications for human obesity since palatable food and exercise may modulate similar reward circuits. PMID:24624109

Improved Robust Stability Criterion of Networked Control Systems with Transmission Delays and Packet Loss

Directory of Open Access Journals (Sweden)

Shenping Xiao

2014-01-01

Full Text Available The problem of stability analysis for a class of networked control systems (NCSs with network-induced delay and packet dropout is investigated in this paper. Based on the working mechanism of zero-order holder, the closed-loop NCS is modeled as a continuous-time linear system with input delay. By introducing a novel Lyapunov-Krasovskii functional which splits both the lower and upper bounds of the delay into two subintervals, respectively, and utilizes reciprocally convex combination technique, a new stability criterion is derived in terms of linear matrix inequalities. Compared with previous results in the literature, the obtained stability criterion is less conservative. Numerical examples demonstrate the validity and feasibility of the proposed method.

Impact of long-term HPN on daily life in adults

NARCIS (Netherlands)

Persoon, Anke; Huisman-de Waal, Getty; Naber, Ton A.; Schoonhoven, Lisette; Tas, Tirzah; Sauerwein, Hans; van Achterberg, Theo

2005-01-01

Home parenteral nutrition (HPN) is a therapy that changes life radically and often means lifelong dependence on parenteral feeding. The aim of this study was to gain insight into problems experienced by adult patients who were dependent on long-term HPN. A survey was performed on all patients at the

Stabilization of wave equations with variable coefficient and delay in the dynamical boundary feedback

Directory of Open Access Journals (Sweden)

Dandan Guo

2017-08-01

Full Text Available In this article we consider the boundary stabilization of a wave equation with variable coefficients. This equation has an acceleration term and a delayed velocity term on the boundary. Under suitable geometric conditions, we obtain the exponential decay for the solutions. Our proof relies on the geometric multiplier method and the Lyapunov approach.

Impulsive control of time-delay systems using delayed impulse and its application to impulsive master-slave synchronization

International Nuclear Information System (INIS)

Sun Jitao; Han Qinglong; Jiang Xiefu

2008-01-01

This Letter is concerned with impulsive control of a class of nonlinear time-delay systems. Some uniform stability criteria for the closed-loop time-delay system under delayed impulsive control are derived by using piecewise Lyapunov functions. Then the criteria are applied to impulsive master-slave synchronization of some secure communication systems with transmission delays and sample delays under delayed impulsive control. Two numerical examples are given to illustrate the effectiveness of the derived results

Prehospital delay in acute coronary syndrome--an analysis of the components of delay

DEFF Research Database (Denmark)

Ottesen, Michael Mundt; Dixen, Ulrik; Torp-Pedersen, Christian

2004-01-01

BACKGROUND: Prompt hospital admission is essential when treating acute coronary syndrome. Delay prior to admission is unnecessarily long. Therefore, a thorough scrutiny of the influence of characteristics, circumstantial and subjective variables on elements of prehospital delay among patients...... admitted with acute coronary syndrome is warranted. METHODS: A structured interview was conducted on 250 consecutive patients admitted alive with acute coronary syndrome. RESULTS: Median prehospital, decision, physician and transportation delays were 107, 74, 25 and 22 min, respectively. Women (n=77) had...... of acute coronary syndrome among women, and thereby contributes to unnecessary long delay to treatment. The patient's prior experience and interpretation has a significant influence on behaviour....

Communication key using delay times in time-delayed chaos synchronization

International Nuclear Information System (INIS)

Kim, Chil-Min; Kye, Won-Ho; Rim, Sunghwan; Lee, Soo-Young

2004-01-01

We propose an efficient key scheme, which can generate a great number of communication keys, for communication using chaos synchronization. We have attained the keys from delay times of time-delay coupled chaotic systems. We explain the scheme and the efficiency by coupling Henon and logistic maps and illustrate them by coupling Navier-Stokes and Lorenz equations as a continuous system

Time delay between singly and doubly ionizing wavepackets in laser-driven helium

International Nuclear Information System (INIS)

Parker, J S; Doherty, B J S; Meharg, K J; Taylor, K T

2003-01-01

We present calculations of the time delay between single and double ionization of helium, obtained from full-dimensionality numerical integrations of the helium-laser Schroedinger equation. The notion of a quantum mechanical time delay is defined in terms of the interval between correlated bursts of single and double ionization. Calculations are performed at 390 and 780 nm in laser intensities that range from 2 x 10 14 to 14 x 10 14 Wcm -2 . We find results consistent with the rescattering model of double ionization but supporting its classical interpretation only at 780 nm. (letter to the editor)

Hopf bifurcations of a ratio-dependent predator–prey model involving two discrete maturation time delays

International Nuclear Information System (INIS)

Karaoglu, Esra; Merdan, Huseyin

2014-01-01

Highlights: • A ratio-dependent predator–prey system involving two discrete maturation time delays is studied. • Hopf bifurcations are analyzed by choosing delay parameters as bifurcation parameters. • When a delay parameter passes through a critical value, Hopf bifurcations occur. • The direction of bifurcation, the period and the stability of periodic solution are also obtained. - Abstract: In this paper we give a detailed Hopf bifurcation analysis of a ratio-dependent predator–prey system involving two different discrete delays. By analyzing the characteristic equation associated with the model, its linear stability is investigated. Choosing delay terms as bifurcation parameters the existence of Hopf bifurcations is demonstrated. Stability of the bifurcating periodic solutions is determined by using the center manifold theorem and the normal form theory introduced by Hassard et al. Furthermore, some of the bifurcation properties including direction, stability and period are given. Finally, theoretical results are supported by some numerical simulations

Hyperactivity and frustration: the influence of control over and size of rewards in delaying gratification.

Science.gov (United States)

Rapport, M D; Tucker, S B; DuPaul, G J; Merlo, M; Stoner, G

1986-06-01

This study examined the differential effects of frustration on normal children and those diagnosed as having Attention Deficit Disorder with Hyperactivity. Each group consisted of 16 boys between the ages of 6 and 8 years who were prematched for age, grade, and classroom placement. All children completed a series of arithmetic problems in order to earn toy rewards. Using a variant of Mischel's (1974) delay-of-gratification paradigm, children were presented with two choice-of-delay conditions in a randomly assigned, counterbalanced sequence: a free-choice conflict situation involving a long-passive or short-active reward delay, and a short-active delay. Results showed that a significantly greater proportion of hyperactive children chose to complete problems for an immediate reward compared to their normal control counterparts (p less than .01). Group differences were no longer apparent in the short-active delay trial. The results are discussed in terms of frustration tolerance and contributing factors such as cognitive-attentional style. Implications for treatment and future directions are delineated.

Patient delay is the main cause of treatment delay in acute limb ischemia: an investigation of pre- and in-hospital time delay

DEFF Research Database (Denmark)

Londero, Louise Skovgaard; Nørgaard, Birgitte; Houlind, Kim Christian

2014-01-01

Abstract BACKGROUND: The prognosis of acute limb ischemia is severe, with amputation rates of up to 25% and in-hospital mortality of 9-15%. Delay in treatment increases the risk of major amputation and may be present at different stages, including patient delay, doctors´ delay and waiting time...... in the emergency department. It is important to identify existing problems in order to reduce time delay. The aim of this study was to collect data for patients with acute limb ischemia and to evaluate the time delay between the different events from onset of symptoms to specialist evaluation and further treatment...... (median (range)) was identified. From onset of symptoms to first contact with a doctor the time for all patients were 24 (0-1200) hours. Thirty patients needed immediate intervention. In the group of fourteen patients who had immediate operation, the median time from vascular evaluation...

Short-Term and Working Memory Impairments in Early-Implanted, Long-Term Cochlear Implant Users Are Independent of Audibility and Speech Production.

Science.gov (United States)

AuBuchon, Angela M; Pisoni, David B; Kronenberger, William G

2015-01-01

To determine whether early-implanted, long-term cochlear implant (CI) users display delays in verbal short-term and working memory capacity when processes related to audibility and speech production are eliminated. Twenty-three long-term CI users and 23 normal-hearing controls each completed forward and backward digit span tasks under testing conditions that differed in presentation modality (auditory or visual) and response output (spoken recall or manual pointing). Normal-hearing controls reproduced more lists of digits than the CI users, even when the test items were presented visually and the responses were made manually via touchscreen response. Short-term and working memory delays observed in CI users are not due to greater demands from peripheral sensory processes such as audibility or from overt speech-motor planning and response output organization. Instead, CI users are less efficient at encoding and maintaining phonological representations in verbal short-term memory using phonological and linguistic strategies during memory tasks.

Associations among daily stressors and salivary cortisol: findings from the National Study of Daily Experiences.

Science.gov (United States)

Stawski, Robert S; Cichy, Kelly E; Piazza, Jennifer R; Almeida, David M

2013-11-01

While much research has focused on linking stressful experiences to emotional and biological reactions in laboratory settings, there is an emerging interest in extending these examinations to field studies of daily life. The current study examined day-to-day associations among naturally occurring daily stressors and salivary cortisol in a national sample of adults from the second wave of the National Study of Daily Experiences (NSDE). A sample of 1694 adults (age=57, range=33-84; 44% male) completed telephone interviews detailing their stressors and emotions on eight consecutive evenings. Participants also provided saliva samples upon waking, 30min post-waking, before lunch and before bed, on four consecutive interview days resulting in 5995 days of interview/cortisol data. Analyses revealed three main findings. First, cortisol AUC was significantly higher on stressor days compared to stressor-free days, particularly for arguments and overloads at home, suggesting that daily stressors are associated with increased cortisol output, but that not all daily stressors have such an influence. Second, individuals reporting a greater frequency of stressor days also exhibited a steeper diurnal cortisol slope. Finally, daily stressor-cortisol associations were unaltered after adjustment for daily negative affect and physical symptoms. Our discussion focuses on the influence of naturally occurring daily stressors on daily cortisol and the role of daily diary approaches for studying healthy cortisol responses to psychosocial stressors outside of traditional laboratory settings. Copyright © 2013 Elsevier Ltd. All rights reserved.

Associations among Daily Stressors and Salivary Cortisol: Findings from the National Study of Daily Experiences

Science.gov (United States)

Stawski, Robert S.; Cichy, Kelly E.; Piazza, Jennifer R.; Almeida, David M.

2013-01-01

While much research has focused on linking stressful experiences to emotional and biological reactions in laboratory settings, there is an emerging interest in extending these examinations to field studies of daily life. The current study examined day-to-day associations among naturally-occurring daily stressors and salivary cortisol in a national sample of adults from the second wave of the National Study of Daily Experiences (NSDE). A sample of 1,694 adults (Age=57, Range=33–84; 44% male) completed telephone interviews detailing their stressors and emotions on eight consecutive evenings. Participants also provided saliva samples upon waking, 30 minutes post-waking, before lunch and before bed, on four consecutive interview days resulting in 5,995 days of interview/cortisol data. Analyses revealed three main findings. First, cortisol AUC was significantly higher on stressor days compared to stressor-free days, particularly for arguments and overloads at home, suggesting that daily stressors are associated with increased cortisol output, but that not all daily stressors have such an influence. Second, individuals reporting a greater frequency of stressor days also exhibited a steeper diurnal cortisol slope. Finally, daily stressor-cortisol associations were unaltered after adjustment for daily negative affect and physical symptoms. Our discussion focuses on the influence of naturally-occurring daily stressors on daily cortisol and the role of daily diary approaches for studying healthy cortisol responses to psychosocial stressors outside of traditional laboratory settings. PMID:23856186

Vehicle barrier with access delay

Science.gov (United States)

Swahlan, David J; Wilke, Jason

2013-09-03

An access delay vehicle barrier for stopping unauthorized entry into secure areas by a vehicle ramming attack includes access delay features for preventing and/or delaying an adversary from defeating or compromising the barrier. A horizontally deployed barrier member can include an exterior steel casing, an interior steel reinforcing member and access delay members disposed within the casing and between the casing and the interior reinforcing member. Access delay members can include wooden structural lumber, concrete and/or polymeric members that in combination with the exterior casing and interior reinforcing member act cooperatively to impair an adversarial attach by thermal, mechanical and/or explosive tools.

Treatment of streptococcal pharyngitis with once-daily compared with twice-daily amoxicillin: a noninferiority trial.

Science.gov (United States)

Clegg, Herbert W; Ryan, Amy G; Dallas, Steven D; Kaplan, Edward L; Johnson, Dwight R; Norton, H James; Roddey, Oliver F; Martin, Edward S; Swetenburg, Raymond L; Koonce, Elizabeth W; Felkner, Mary M; Giftos, P Michael

2006-09-01

Two relatively small previous studies comparing once-daily amoxicillin with conventional therapy for group A streptococcal (GAS) pharyngitis reported similar rates of bacteriologic success for each treatment group. The purpose of this study was to further evaluate once-daily amoxicillin for GAS pharyngitis in a larger study. In a single pediatric practice, from October through May for 2 consecutive years (2001-2003), we recruited children 3 to 18 years of age who had symptoms and signs suggestive of GAS pharyngitis. Patients with a positive rapid test for GAS were stratified by weight (or=40 kg) and then randomly assigned to receive once-daily (750 mg or 1000 mg) or twice-daily (2 doses of 375 mg or 500 mg) amoxicillin for 10 days. We determined bacteriologic failure rates for GAS in the pharynx from subsequent swabs taken at 14 to 21 (visit 2) and 28 to 35 (visit 3) days after treatment initiation. We conducted a randomized, controlled, investigator-blinded, noninferiority trial to evaluate whether amoxicillin given once daily would have a bacteriologic failure rate no worse than that of amoxicillin given twice daily within a prespecified margin of 10%. GAS isolates were characterized to distinguish bacteriologic failures from new acquisitions. Adverse events were described and adherence was evaluated by review of returned daily logs and dosage bottles. Of 2139 potential study patients during the 2-year period, we enrolled 652 patients, 326 into each treatment group. Children in the 2 groups were comparable with respect to all demographic and clinical characteristics except that children <40 kg more often presented with rash in each treatment group. At visit 2, failure rates were 20.1% (59 of 294) for the once-daily group and 15.5% (46 of 296) for the twice-daily group (difference, 4.53%; 90% confidence interval [CI], -0.6 to 9.7). At visit 3, failure rates were 2.8% (6 of 216) for the once-daily group and 7.1% (16 of 225) for the twice-daily group (difference, -4

Using daily excessive concentration hours to explore the short-term mortality effects of ambient PM2.5 in Hong Kong

International Nuclear Information System (INIS)

Lin, Hualiang; Ma, Wenjun; Qiu, Hong; Wang, Xiaojie; Trevathan, Edwin; Yao, Zhenjiang; Dong, Guang-Hui; Vaughn, Michael G.; Qian, Zhengmin; Tian, Linwei

2017-01-01

We developed a novel indicator, daily excessive concentration hours (DECH), to explore the acute mortality impacts of ambient fine particulate matter pollution (PM 2.5 ) in Hong Kong. The DECH of PM 2.5 was calculated as daily concentration-hours >25 μg/m 3 . We applied a generalized additive models to quantify the association between DECH and mortality with adjustment for potential confounders. The results showed that the DECH was significantly associated with mortality. The excess mortality risk for an interquartile range (565 μg/m 3 *hours) increase in DECH of PM 2.5 was 1.65% (95% CI: 1.05%, 2.26%) for all natural mortality at lag 02 day, 2.01% (95% CI: 0.82%, 3.21%) for cardiovascular mortality at lag 03 days, and 1.41% (95% CI: 0.34%, 2.49%) for respiratory mortality at lag 2 day. The associations remained consistent after adjustment for gaseous air pollutants (daily mean concentration of SO 2 , NO 2 and O 3 ) and in alternative model specifications. When compared to the mortality burden of daily mean PM 2.5 , DECH was found to be a relatively conservative indicator. This study adds to the evidence by showing that daily excessive concentration hours of PM 2.5 might be a new predictor of mortality in Hong Kong. - Highlights: • A new indicator, daily excess concentration hours (DECH), was proposed in this study. • DECH of PM 2.5 was associated with cardiovascular mortality in Hong Kong. • DECH of PM 2.5 was associated with respiratory mortality in Hong Kong. - Excessive concentration hours of PM 2.5 , as one new indicator, is significantly associated with increased mortality in Hong Kong.

Daily Management System of the Henry Ford Production System: QTIPS to Focus Continuous Improvements at the Level of the Work.

Science.gov (United States)

Zarbo, Richard J; Varney, Ruan C; Copeland, Jacqueline R; D'Angelo, Rita; Sharma, Gaurav

2015-07-01

To support our Lean culture of continuous improvement, we implemented a daily management system designed so critical metrics of operational success were the focus of local teams to drive improvements. We innovated a standardized visual daily management board composed of metric categories of Quality, Time, Inventory, Productivity, and Safety (QTIPS); frequency trending; root cause analysis; corrective/preventive actions; and resulting process improvements. In 1 year (June 2013 to July 2014), eight laboratory sections at Henry Ford Hospital employed 64 unique daily metrics. Most assessed long-term (>6 months), monitored process stability, while short-term metrics (1-6 months) were retired after successful targeted problem resolution. Daily monitoring resulted in 42 process improvements. Daily management is the key business accountability subsystem that enabled our culture of continuous improvement to function more efficiently at the managerial level in a visible manner by reviewing and acting based on data and root cause analysis. Copyright© by the American Society for Clinical Pathology.

Delay-dependent asymptotic stability of mobile ad-hoc networks: A descriptor system approach

International Nuclear Information System (INIS)

Yang Juan; Yang Dan; Zhang Xiao-Hong; Huang Bin; Luo Jian-Lu

2014-01-01

In order to analyze the capacity stability of the time-varying-propagation and delay-dependent of mobile ad-hoc networks (MANETs), in this paper, a novel approach is proposed to explore the capacity asymptotic stability for the delay-dependent of MANETs based on non-cooperative game theory, where the delay-dependent conditions are explicitly taken into consideration. This approach is based on the Lyapunov—Krasovskii stability theory for functional differential equations and the linear matrix inequality (LMI) technique. A corresponding Lyapunov—Krasovskii functional is introduced for the stability analysis of this system with use of the descriptor and “neutral-type” model transformation without producing any additional dynamics. The delay-dependent stability criteria are derived for this system. Conditions are given in terms of linear matrix inequalities, and for the first time referred to neutral systems with the time-varying propagation and delay-dependent stability for capacity analysis of MANETs. The proposed criteria are less conservative since they are based on an equivalent model transformation. Furthermore, we also provide an effective and efficient iterative algorithm to solve the constrained stability control model. Simulation experiments have verified the effectiveness and efficiency of our algorithm. (general)

New Daily Persistent Headache: Historical Review and an Interview with Dr. Walter Vanast.

Science.gov (United States)

Robbins, Matthew S; Vanast, Walter J; Allan Purdy, R

2017-06-01

New daily persistent headache (NDPH) is an idiopathic headache syndrome characterized by the abrupt onset of an unremitting, daily, continuous headache without an antecedent escalating headache pattern, and not attributable to other primary or secondary headache disorders. We review the history of NDPH in terms of its characterization and classification, and then interview Dr. Walter Vanast, the neurologist who initially described NDPH three decades ago, to gain his perspective now that there is more widespread recognition and interest in this syndrome. © 2017 American Headache Society.

Delay discounting of oral morphine and sweetened juice rewards in dependent and non-dependent rats.

Science.gov (United States)

Harvey-Lewis, Colin; Perdrizet, Johnna; Franklin, Keith B J

2014-07-01

Opioid-dependent humans are reported to show accelerated delay discounting of opioid rewards when compared to monetary rewards. It has been suggested that this may reflect a difference in discounting of consumable and non-consumable goods not specific to dependent individuals. Here, we evaluate the discounting of similar morphine and non-morphine oral rewards in dependent and non-dependent rats We first tested the analgesic and rewarding effects of our morphine solution. In a second experiment, we assigned rats randomly to either dependent or non-dependent groups that, 30 min after daily testing, received 30 mg/kg subcutaneous dose of morphine, or saline, respectively. Delay discounting of drug-free reward was examined prior to initiation of the dosing regimen. We tested discounting of the morphine reward in half the rats and retested the discounting of the drug-free reward in the other half. All tests were run 22.5 h after the daily maintenance dose. Rats preferred the morphine cocktail to the drug-free solution and consumed enough to induce significant analgesia. The control quinine solution did not produce these effects. Dependent rats discounted morphine rewards more rapidly than before dependence and when compared to discounting drug-free rewards. In non-dependent rats both reward types were discounted similarly. These results show that morphine dependence increases impulsiveness specifically towards a drug reward while morphine experience without dependence does not.

Precise delay measurement through combinatorial logic

Science.gov (United States)

Burke, Gary R. (Inventor); Chen, Yuan (Inventor); Sheldon, Douglas J. (Inventor)

2010-01-01

A high resolution circuit and method for facilitating precise measurement of on-chip delays for FPGAs for reliability studies. The circuit embeds a pulse generator on an FPGA chip having one or more groups of LUTS (the "LUT delay chain"), also on-chip. The circuit also embeds a pulse width measurement circuit on-chip, and measures the duration of the generated pulse through the delay chain. The pulse width of the output pulse represents the delay through the delay chain without any I/O delay. The pulse width measurement circuit uses an additional asynchronous clock autonomous from the main clock and the FPGA propagation delay can be displayed on a hex display continuously for testing purposes.

Improving Delay-Range-Dependent Stability Condition for Systems with Interval Time-Varying Delay

Directory of Open Access Journals (Sweden)

Wei Qian

2013-01-01

Full Text Available This paper discusses the delay-range-dependent stability for systems with interval time-varying delay. Through defining the new Lyapunov-Krasovskii functional and estimating the derivative of the LKF by introducing new vectors, using free matrices and reciprocally convex approach, the new delay-range-dependent stability conditions are obtained. Two well-known examples are given to illustrate the less conservatism of the proposed theoretical results.

Identifying and comparing states of time-delayed systems: phase diagrams and applications to human motor control systems

International Nuclear Information System (INIS)

Frank, T.D.; Friedrich, R.; Beek, P.J.

2005-01-01

A data driven characterization of time-delayed stochastic systems is proposed in terms of linear delay differential equations and two drift parameters. It is shown how these parameters determine the states of such systems with respect to generalized phase diagrams. This approach allows for a comparison of systems with different parameters as exemplified for two motor control tasks: tracking and force production

Modeling of delays in PKPD: classical approaches and a tutorial for delay differential equations.

Science.gov (United States)

Koch, Gilbert; Krzyzanski, Wojciech; Pérez-Ruixo, Juan Jose; Schropp, Johannes

2014-08-01

In pharmacokinetics/pharmacodynamics (PKPD) the measured response is often delayed relative to drug administration, individuals in a population have a certain lifespan until they maturate or the change of biomarkers does not immediately affects the primary endpoint. The classical approach in PKPD is to apply transit compartment models (TCM) based on ordinary differential equations to handle such delays. However, an alternative approach to deal with delays are delay differential equations (DDE). DDEs feature additional flexibility and properties, realize more complex dynamics and can complementary be used together with TCMs. We introduce several delay based PKPD models and investigate mathematical properties of general DDE based models, which serve as subunits in order to build larger PKPD models. Finally, we review current PKPD software with respect to the implementation of DDEs for PKPD analysis.

A distributed delay approach for modeling delayed outcomes in pharmacokinetics and pharmacodynamics studies.

Science.gov (United States)

Hu, Shuhua; Dunlavey, Michael; Guzy, Serge; Teuscher, Nathan

2018-04-01

A distributed delay approach was proposed in this paper to model delayed outcomes in pharmacokinetics and pharmacodynamics studies. This approach was shown to be general enough to incorporate a wide array of pharmacokinetic and pharmacodynamic models as special cases including transit compartment models, effect compartment models, typical absorption models (either zero-order or first-order absorption), and a number of atypical (or irregular) absorption models (e.g., parallel first-order, mixed first-order and zero-order, inverse Gaussian, and Weibull absorption models). Real-life examples were given to demonstrate how to implement distributed delays in Phoenix ® NLME™ 8.0, and to numerically show the advantages of the distributed delay approach over the traditional methods.

Delayed reproductive death as a dominant phenotype in cell clones surviving X-irradiation

International Nuclear Information System (INIS)

Chang, W.P.; Little, J.B.

1992-01-01

Residual damage manifested as reduced cloning efficiency was observed in many of the cloned progeny of Chinese hamster ovary (CHO) cells and human carcinoma SQ-20B cells surviving X-irradiation. This stable phenotype, which we have termed delayed reproductive death, persisted for >50 generations of cell replication post-irradiation. Clones showing this phenotype were aneuploid, and formed colonies with a high proportion of giant cells. By somatic cell hybridization of CHO clones, the delayed reproductive death phenotype was found to be a dominant trait; the cloning efficiency of hybrid clones was persistently depressed, as compared with that of control hybrid cells. These results suggest that delayed reproductive death represents a specific cellular response that may persist in some of the progeny of mammalian cells for long periods after X-irradiation. (author)

Bifurcation and Stability in a Delayed Predator-Prey Model with Mixed Functional Responses

Science.gov (United States)

Yafia, R.; Aziz-Alaoui, M. A.; Merdan, H.; Tewa, J. J.

2015-06-01

The model analyzed in this paper is based on the model set forth by Aziz Alaoui et al. [Aziz Alaoui & Daher Okiye, 2003; Nindjin et al., 2006] with time delay, which describes the competition between the predator and prey. This model incorporates a modified version of the Leslie-Gower functional response as well as that of Beddington-DeAngelis. In this paper, we consider the model with one delay consisting of a unique nontrivial equilibrium E* and three others which are trivial. Their dynamics are studied in terms of local and global stabilities and of the description of Hopf bifurcation at E*. At the third trivial equilibrium, the existence of the Hopf bifurcation is proven as the delay (taken as a parameter of bifurcation) that crosses some critical values.

Time Delay of CGM Sensors

Science.gov (United States)

Schmelzeisen-Redeker, Günther; Schoemaker, Michael; Kirchsteiger, Harald; Freckmann, Guido; Heinemann, Lutz; del Re, Luigi

2015-01-01

Background: Continuous glucose monitoring (CGM) is a powerful tool to support the optimization of glucose control of patients with diabetes. However, CGM systems measure glucose in interstitial fluid but not in blood. Rapid changes in one compartment are not accompanied by similar changes in the other, but follow with some delay. Such time delays hamper detection of, for example, hypoglycemic events. Our aim is to discuss the causes and extent of time delays and approaches to compensate for these. Methods: CGM data were obtained in a clinical study with 37 patients with a prototype glucose sensor. The study was divided into 5 phases over 2 years. In all, 8 patients participated in 2 phases separated by 8 months. A total number of 108 CGM data sets including raw signals were used for data analysis and were processed by statistical methods to obtain estimates of the time delay. Results: Overall mean (SD) time delay of the raw signals with respect to blood glucose was 9.5 (3.7) min, median was 9 min (interquartile range 4 min). Analysis of time delays observed in the same patients separated by 8 months suggests a patient dependent delay. No significant correlation was observed between delay and anamnestic or anthropometric data. The use of a prediction algorithm reduced the delay by 4 minutes on average. Conclusions: Prediction algorithms should be used to provide real-time CGM readings more consistent with simultaneous measurements by SMBG. Patient specificity may play an important role in improving prediction quality. PMID:26243773

Glucagon-Like Peptide-1 Analog, Liraglutide, Delays Onset of Experimental Autoimmune Encephalitis in Lewis Rats

DEFF Research Database (Denmark)

DellaValle, Brian; Brix, Gitte S; Brock, Birgitte

2016-01-01

(GLP-1) family, is also anti-diabetic and weight-reducing and is, moreover, directly neuroprotective and anti-inflammatory in a broad spectrum of experimental models of brain disease. In this study we investigate the potential for this FDA-approved drug, liraglutide, as a treatment for MS by utilizing...... the experimental model, experimental autoimmune encephalitis (EAE). Methods: EAE was induced in 30 female Lewis rats that subsequently received twice-daily liraglutide (200 μg/kg s.c.) or saline. Healthy controls were included (saline, n = 6, liraglutide, n = 7). Clinical score and weight were assessed daily...... treatment delayed disease onset (group clinical score significantly >0) by 2 days and markedly reduced disease severity (median clinical score 2 vs. 5; p = 0.0003). Fourteen of 15 (93%) of vehicle-treated rats reached the humane endpoint (clinical score ≥4) by day 11 compared to 5 of 15 (33%) of liraglutide...

Goal conflict and goal facilitation as predictors of daily accelerometer-assessed physical activity.

Science.gov (United States)

Presseau, Justin; Tait, Richard I; Johnston, Derek W; Francis, Jill J; Sniehotta, Falko F

2013-12-01

To test whether perceptions of conflicting and facilitating personal goals, and actual daily time spent in their pursuit, predict accelerometer-assessed physical activity (PA). A prospective multilevel design with a daily accelerometer-based assessment of PA over 1 week was used (N = 106). Participants' personal goals were elicited using personal projects analysis. Participants then rated their personal goals in terms of how they were perceived to facilitate and conflict with their regular PA. Items assessing PA-specific intention and perceived behavioral control (PBC) were also embedded within the baseline measures. For the subsequent 7 consecutive days, participants completed a daily diary based on the day reconstruction method, indicating the time spent in daily episodes involving each of their personal goals, and wore an RT3 tri-axial accelerometer. The main outcome was accelerometer-assessed daily time spent in moderate to vigorous physical activity (MVPA). Random intercept multilevel models indicated that perceived goal facilitation, but not perceived goal conflict, predicted MVPA over and above intention and PBC. Daily time pursuing conflicting goals negatively predicted MVPA when subsequently added to the model and in so doing, attenuated the association between perceived goal facilitation and MVPA. Perceived goal facilitation predicts objectively measured PA over and above intention and PBC, but daily time spent in pursuit of conflicting personal goals provides a better account of how alternative goals relate to engaging in regular PA.

Quad nanosecond delay module

International Nuclear Information System (INIS)

McDonald, R.J.; Hunter, J.B.; Wozniak, G.J.

1986-04-01

Four nanosecond (ns) delay units have been designed to fit in a single-width NIM module. This module is particularly suited for use in conjunction with quad constant fraction timing discriminators (CFTDs) since it has four delay units that can be placed adjacent to the four units of the CFTD. A series of different length cables connected via DIP toggle switches provide delays of 0.60 ns in 4 ns increments. Thus, the CFTD delay can be optimized for pulses of different rise times from approx.10-100 ns. Design work for the PC board and silkscreening of the front panel were done with the MacDraw program on the Apple Mackintosh computer and printed with the Lasewriter printer. 6 refs

A simple delay model for two-phase flow dynamics

Energy Technology Data Exchange (ETDEWEB)

Clausse, A.; Delmastro, D.F.; Juanico`, L.E. [Centro Atomico Bariloche (Argentina)

1995-09-01

A model based in delay equations for density-wave oscillations is presented. High Froude numbers and moderate ones were considered. The equations were numerically analyzed and compared with more sophisticated models. The influence of the gravity term was studied. Different kinds of behavior were found, particularly sub-critical and super-critical Hopf bifurcations. Moreover the present approach can be used to better understand the complicated dynamics of boiling flows systems.

LMI optimization approach to stabilization of time-delay chaotic systems

International Nuclear Information System (INIS)

Park, Ju H.; Kwon, O.M.

2005-01-01

Based on the Lyapunov stability theory and linear matrix inequality (LMI) technique, this paper proposes a novel control method for stabilization of a class of time-delay chaotic systems. A stabilization criterion is derived in terms of LMIs which can be easily solved by efficient convex optimization algorithms. A numerical example is included to show the advantage of the result derived

Task-irrelevant distractors in the delay period interfere selectively with visual short-term memory for spatial locations.

Science.gov (United States)

Marini, Francesco; Scott, Jerry; Aron, Adam R; Ester, Edward F

2017-07-01

Visual short-term memory (VSTM) enables the representation of information in a readily accessible state. VSTM is typically conceptualized as a form of "active" storage that is resistant to interference or disruption, yet several recent studies have shown that under some circumstances task-irrelevant distractors may indeed disrupt performance. Here, we investigated how task-irrelevant visual distractors affected VSTM by asking whether distractors induce a general loss of remembered information or selectively interfere with memory representations. In a VSTM task, participants recalled the spatial location of a target visual stimulus after a delay in which distractors were presented on 75% of trials. Notably, the distractor's eccentricity always matched the eccentricity of the target, while in the critical conditions the distractor's angular position was shifted either clockwise or counterclockwise relative to the target. We then computed estimates of recall error for both eccentricity and polar angle. A general interference model would predict an effect of distractors on both polar angle and eccentricity errors, while a selective interference model would predict effects of distractors on angle but not on eccentricity errors. Results showed that for stimulus angle there was an increase in the magnitude and variability of recall errors. However, distractors had no effect on estimates of stimulus eccentricity. Our results suggest that distractors selectively interfere with VSTM for spatial locations.

Daily stressors and emotional reactivity in individuals with mild cognitive impairment and cognitively healthy controls.

Science.gov (United States)

Rickenbach, Elizabeth Hahn; Condeelis, Kristen L; Haley, William E

2015-06-01

Daily experiences of stress are common and have been associated with worse affect among older adults. People with mild cognitive impairment (PWMCI) have measurable memory deficits in between normal cognition and dementia and have been identified as having greater psychological distress than cognitively healthy older adults (CHOAs). Little is known about whether daily stressors contribute to distress among PWMCI. We hypothesized that compared with CHOAs, PWMCI would have higher daily negative affect and lower daily positive affect, report greater numbers and severity of daily stressors, and experience greater emotional reactivity to daily stressors. Fifteen clinically diagnosed PWMCI and 25 CHOAs completed daily reports of stressors, stressor severity, and positive and negative affect over an 8-day period. PWMCI reported higher daily negative affect, lower daily positive affect, and higher numbers and greater severity of memory stressors but did not differ from CHOAs in numbers or severity of general stressors. Cognitive status was a moderator of the daily stress-affect relationship. Days with greater numbers and severity of general daily stressors were associated with higher negative affect only for PWMCI. The numbers and severity of memory stressors were not associated with negative affect. In addition, more severe general daily stressors and memory stressors were associated with lower positive affect for all participants. Results suggest that PWMCI are less resilient in the face of daily stress than are CHOAs in terms of negative affect, perhaps because of declines in reserve capacity. The study presents a promising approach to understanding stress and coping in predementia states of cognition. (c) 2015 APA, all rights reserved.

Does delay in diagnosing colorectal cancer in symptomatic patients affect tumor stage and survival? A population-based observational study

Directory of Open Access Journals (Sweden)

Visser Otto

2010-06-01

Full Text Available Abstract Background Diagnosing colorectal cancer (CRC at an early stage improves survival. To what extent any delay affects outcome once patients are symptomatic is still unclear. Our objectives were to evaluate the association between diagnostic delay and survival in symptomatic patients with early stage CRC and late stage CRC. Methods Prospective population-based observational study evaluating daily clinical practice in Northern Holland. Diagnostic delay was determined through questionnaire-interviews. Dukes' stage was classified into two groups: early stage (Dukes A or B and late stage (Dukes C or D cancer. Patients were followed up for 3.5 years after diagnosis. Results In total, 272 patients were available for analysis. Early stage CRC was present in 136 patients while 136 patients had late stage CRC. The mean total diagnostic delay (SE was 31 (1.5 weeks in all CRC patients. No significant difference was observed in the mean total diagnostic delay in early versus late stage CRC (p = 0.27. In early stage CRC, no difference in survival was observed between patients with total diagnostic delay shorter and longer than the median (Kaplan-Meier, log-rank p = 0.93. In late stage CRC, patients with a diagnostic delay shorter than the median had a shorter survival than patients with a diagnostic delay longer than the median (log-rank p = 0.01. In the multivariate Cox regression model with survival as dependent variable and median delay, age, open access endoscopy, number and type of symptoms as independent variables, the odd's ratio for survival in patients with long delay (>median versus short delay (≤median was 1.8 (95% confidence interval (CI 1.1 to 3.0; p = 0.01. Tumor-site was not associated with patient survival. When separating late stage CRC in Dukes C and Dukes D tumors, a shorter delay was associated with a shorter survival in Dukes D tumors only and not in Dukes C tumors. Conclusion In symptomatic CRC patients, a longer diagnostic and

Personal Risk and Resilience Factors in the Context of Daily Stress

Science.gov (United States)

Diehl, Manfred; Hay, Elizabeth L.; Chui, Helena

2012-01-01

This chapter focuses on the role that personal risk and resilience factors play as adults of all ages cope with the stressors encountered in everyday life. Theorists have suggested that researchers should focus on the effects of daily stress and coping rather than focusing exclusively on major life events and chronic stress and have proposed that understanding how adults cope with daily stress is a key aspect of understanding long-term well-being and adaptation in adulthood. After presenting a conceptual model outlining the major components of the daily stress process, the chapter reviews the existing empirical literature on personal risk and resilience factors in the context of daily stress. This research clearly suggests that there is no universal generalization that can be made regarding whether chronological age, in and of itself, confers greater vulnerability or resilience onto adults. Instead, we argue that researchers should ask when and under what conditions is age associated with greater vulnerability to daily stress and when and under what conditions is age associated with greater resilience to daily stress. Age differences in reactivity to daily stress are clearly embedded within a complex system of factors—structural, individual, and situational—that influence stress reactivity and stress recovery in several ways. This complexity should not be taken to mean that stress reactivity and recovery cannot be charted or understood. Researchers, however, will need to approach this complexity with a great deal of theoretical, methodological, and statistical rigor to move our understanding of the importance of age in shaping risk and resilience to daily stress forward. The final section of the chapter outlines several directions for future research in the area of aging and resilience. In particular, we argue that a focus on personal risk and resilience factors in the context of daily stress, in combination with the application of sophisticated statistical