Daytime Behavior

At surface (300 K, 1 atm) conditions, oh+no2 1 x I0 llcm3 molecule 1 s-1. At [OH] = 106 molecules cm-3, the lifetime of N02 during daytime is about 1 day. The lifetime of the NO chemical family under daytime conditions is given by applying (3.34)  

The value juo2 is essentially constant with altitude in the troposphere. For the calculation, the ozone mixing ratio can be taken as essentially uniform vertically, but [03] decreases with altitude because of the decrease of the number concentration of air. The ratio [N0]/[N02] 1 at the surface, increasing to about 12 at 10 km. Two factors contribute to this increase. First, no+o3 decreases as temperature decreases, slowing down the return of NO to N02. The second factor is the decrease of [03] with altitude, also serving to slow down the rate of the NO + 03 reaction. The lifetime of NO, increases from between 1 and 2 days at the surface to about 2 weeks in the upper troposphere. The relatively short lifetime at the surface is a result of the fact that most of the NO, is in the form of N02 at the surface, and the OH + N02 reaction dominates the lifetime of NO,. In the upper troposphere, the opposite condition holds with most of the NO, in the form of NO, the net removal of NO, by OH + N02 is slowed considerably. 

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Problems related to inadequate sleep in children and adolescents are fairly common. Studies have shown that inadequate or irregular sleep usually results in some variation of daytime sleepiness, but may also result in behavior problems, difficulties with alertness, concentration, attentiveness, problem solving, memory, school problems, and other daytime behavior problems. Adolescents health may also be compromised by poor sleep/wake habits, with increased irritability... 

Owens, J, opipari, L, Nobile, C and Spirito, A (1998) Sleep and daytime behavior in children with obstructive apnea and behavioral sleep disorders. Pediatrics 102 1178-1184. 

These data show that both models identify important variables that affect 5 Obody w.ier and 8 Ophospha in mammals. Both serve to identify the dikdik as an outlier which may be explained by their sedentary daytime pattern. On the other hand, the body-size model (Bryant and Froelich 1995), which may reliably predict animal 5 0 in temperate, well-watered regions, does not predict 8 Opho,phaw in these desert-adapted species. The second model (Kohn 1996), by emphasizing animal physiology independent of body size, serves to identify species with different sensitivities to climatic parameters. This, in conjunction with considerations of behavior, indicate that certain species are probably not useful for monitoring paleotemperature because their 5 Obodyw er is not tied, in a consistent way, to The oryx, for example, can... 

Sleep-wake state alterations in PD can be broadly classified into disturbances of (1) thalamocortical arousal state and (2) excessive nocturnal movement (Rye and Bliwise 2004 Rye and Iranzo 2005). The former includes the loss of sleep spindles and SWS, daytime sleepiness, and intrusion of REM sleep into daytime naps (i.e. sleep onset REM periods, or SOREMs), and the latter encompass periodic leg movements of sleep (PLMs) and REM sleep behavior disorder (RBD). The pathophysiological basis of sleepiness and SOREMs appears to be dopaminergic cell loss in PD, though excessive nocturnal movements are not as clearly related to dopaminergic deficits. 

Rye D., Daley J., Freeman A., Bliwise D. (2003). Daytime sleepiness and sleep attacks in idiopathic parkinson s disease. In Bedard M-A., Agid Y., Chouinard S. et al. editors. Mental and Behavioral Dysfunction in Movement Disorders. Totawa, NJ Humana Press pp. 527-38. 

Rye D., Johnston L., Watts R., Bliwise D. (1999). Juvenile Parkinson s disease with REM behavior disorder, sleepiness and daytime REM-onsets. Neurology 53, 1868-70. 

The patient experiences anxiety, apathy, bradyphrenia (slowness of thought processes), confusional state, dementia, depression, hallucinosis/psychosis (typically drug-induced), and sleep disorders (excessive daytime sleepiness, insomnia, obstructive sleep apnea, and rapid eye movement sleep behavior disorder). 

Sometimes bad sleep habits develop during the period of stress. This is termed poor sleep hygiene and it may consist of taking daytime naps, drinking a nightcap, or engaging in other behaviors that ultimately interfere with quality nighttime sleep. When such bad sleep habits persist after the initial stress has passed, then a vicious cycle of anxious anticipation and ever-poorer sleep may arise. 

Other Hypersomnias. Narcolepsy is not the only hypersomnia, but it is by far the most common. Primary hypersomnia shares sleep attacks and excessive daytime sleepiness with narcolepsy but does not feature cataplexy or REM-associated abnormalities. Another rare hypersomnia is Kleine-Levin syndrome (KLS), which most often occurs in teenage boys. KLS consists of intermittent bouts of hypersomnia and bizarre behaviors including compulsive eating and sexual inappropriateness. Distinguishing these hypersomnias from narcolepsy may help clarify the patient s prognosis, but the treatment alternatives are very similar. 

Maislin G, Pack AI, Samuel S, Dinges DF. Objectively measured sleep behaviors and vigilance in community residing elderly with and without complaints of daytime sleepiness. Sleep 2001 24S A224. 

Further disruption of REM sleep is related to the presence of hallucinations and REM sleep behavior disorder in Parkinson s patients. A decrease in REM sleep has been associated with nocturnal hallucinations (125), and REM intrusion during daytime hallucinations has been reported (126). More than one third of Parkinson s patients also suffer from REM sleep behavior disorder (RBD) (127,128) or REM sleep without atonia (128). In these patients, there is also a significant reduction in total sleep time. In many cases RBD is diagnosed several years prior to the onset of Parkinson s disease (129), although a link between disease severity and duration and the presence of RBD has also been reported (128). RBD is most often treated with the administration of clonazepam (104,129). Patients with comorbid dementia and depression also experience a high level of sleep disturbance, associated with nocturnal vocalizations and hallucinations (130). One side effect of many antidepressant medications, however, is insomnia and sleep disturbance (131). 

Clearly, more experimental research is needed to tease apart the developmental influences of sleep restriction and/or disruption on a range of daytime functioning behaviors and cognitive skills. Additionally, studies are needed that restrict sleep for extended periods of time to identify deficits that may be associated with the typical sleep patterns of children and adolescents. 

Lichstein KL, Wilson, NM, Noe SL, Aguillard RN, Bellur SN. Daytime sleepiness in insomnia behavioral, biological, and subjective indices. Sleep 1994 17 693-702. 

One could reasonably believe that complaining of chronic daytime somnolence is a major risk for traffic accidents. Surprisingly, studies on patients suffering from chronic daytime somnolence (9,10) failed to find a link between the risk of traffic accidents and sleepiness measured on a behavioral scale (i.e., Epworth Sleepiness Scale). This could be explained by the fact that subjective questionnaires do not correlate with objective measures of daytime vigilance (11). Another possible explanation could be that sleepiness is dangerous only when perceived during at risk activities. 

Studies on apneic subjects (12,13) have shown that chronic subjective daytime somnolence is not responsible for traffic accidents but sleepiness at the wheel while driving is responsible for traffic accidents. These findings confirm the importance of behavioral somnolence and justify the responsibility of this symptom in the occurrence of an accident. 

Subjective (e.g., Epworth Sleepiness Scale) and objective [e.g., Multiple Sleep Latency Test (MSLT)] daytime somnolence quantification does not seem to provide valuable information on patients risks. This could be explained by the fact that sleep-related accidents occur at certain times when behavioral and chronobiological factors play an important role. Medical and legal issues could nevertheless require an objective test, such as the Maintenance of Wakefulness Test (MWT), to confirm that treated apneic patients present a normal level of vigilance. 

Population-based surveys typically have found that a substantial percentage of people report that they do not get sufficient sleep (1). While the exact prevalence may be disputed, it is an accepted fact that many people get insufficient sleep. In addition to those recognizing their insufficient sleep are other individuals who show objective evidence of excessive sleepiness, deny difficulty with sleepiness, and yet show normalization of their alertness with extended time in bed (TIB) (2). Consciously or subconsciously, people employ various stratagems to counteract the disruptive effects of their sleep loss. While the functionally disruptive effects and health risks associated with sleep loss and its consequent daytime sleepiness are generally recognized, questions remain regarding what behavioral and environment factors act as countermeasures to sleep loss and daytime sleepiness, as well as to their effectiveness and duration of effect. 

Anderson MW, Zendell SM, Rubinstein ML, Spielman AJ. Daytime alertness in chronic insomnia diagnostic differences and response to behavioral treatment. Sleep Res 1994 23 217. 

Carskadon M, Dement W. Daytime sleepiness quantification of a behavioral state. Neurosci Biobehav Rev 1987 11 307-317. 

Pediatric sleep disorders are common, have significant effects on daytime functioning of children and families, and most are amenable to some combination of behavioral management strategies and pharmacological treatment. It is particularly important for the primary care physician to screen for sleep problems in children,... 

Randomized, controlled trials of both behavioral and pharmacological treatments for behavioral disturbances using measures of sleep, daytime function, and impact on caregivers, in addition to behavioral and psychiatric outcome measures. 

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