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Littérature scientifique sur le sujet « Nocturnal falls »

Auteur : Grafiati

Publié le 21 décembre 2024

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Articles de revues sur le sujet "Nocturnal falls"

JOHNSON, KATE. « Treatment for Nocturnal Reflux Often Falls Short ». Internal Medicine News 38, n^o 22 (novembre 2005) : 59. http://dx.doi.org/10.1016/s1097-8690(05)72398-2.

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Suman, Sanjay, Dudley Robinson, Nadia Bhal, Susannah Fraser, Angus MacCormick, Ann Williams et Sergey Tadtayev. « Management of nocturia : overcoming the challenges of nocturnal polyuria ». British Journal of Hospital Medicine 80, n^o 9 (2 septembre 2019) : 517–24. http://dx.doi.org/10.12968/hmed.2019.80.9.517.

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Nocturia may be a multifactorial condition and should be regarded as a syndrome rather than a diagnosis, with many factors contributing to the clinical presentation. The effects of sleep deprivation can have a severely detrimental impact on the quality of life and productivity of the working age population, with considerable economic implications. Patients are unlikely to seek an appointment with their GP complaining of nocturia – they are more likely to complain of the effects of the condition, such as chronic tiredness, or injuries resulting from falls. The main criterion in deciding whether a patient should undergo further investigations into suspected nocturia is the degree to which the patient finds the condition bothersome. In some patients, lifestyle modifications may be an effective way to manage nocturia before medication is considered. As the only licensed product for all adults including those over 65 years of age, low dose desmopressin (Noqdirna® (as lyophilisate) Ferring Pharmaceuticals Ltd) is highly effective in the management of idiopathic nocturnal polyuria, producing improvements in clinical symptoms, sleep parameters and quality of life. Care should be administered as a joint enterprise between the patient's GP and colleagues in secondary care. This article outlines the findings of a roundtable discussion into the optimal management of patients with nocturnal polyuria.

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Miyajima, Shigero, Taisei Omaru, Tatsu Ishii, Hisatomi Arima, Yozo Shibata, Teruaki Izaki et Nobuhiro Haga. « Real-World Evidence for Risk Factors of Bruises and Fractures from Falls in Patients with Overactive Bladder : A Medical Record Analysis ». International Journal of Clinical Practice 2023 (27 décembre 2023) : 1–6. http://dx.doi.org/10.1155/2023/3701823.

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Aim. To identify the risk factors for bruises and fractures from falls in patients with overactive bladder (OAB). Methods. We evaluated 1136 patients with OAB and aged ≥50 years who visited our hospital. Age, sex, frequency of nocturnal urination, and urinary incontinence type were investigated in the 360 eligible patients. Patients were divided into three groups: those patients without falls (no-fall group), those with fall bruises (bruise group), and those with fall fractures (fracture group). The risk factors for bruises and fractures in patients with OAB were evaluated using the logistic regression analysis. In addition, association between the bruises or fractures from falls and the behavior around urination during the night was investigated. Results. The multivariate logistic regression analysis showed that female sex (odds ratio (OR) 2.888, p = 0.030) and nocturnal urination frequency ≥3 times/night (OR vs. ≤2 times/night, 2.940; p = 0.040) were significantly associated with bruises. Nocturnal urination frequency ≥3 times/night (OR vs. ≤2 times/night, 2.835; p = 0.026) and urge incontinence (OR 3.415, p = 0.016) were significantly associated with fractures. Behavior around urination during the night was significantly associated with fractures (p = 0.009). Conclusion. In the real-world clinical setting, increasing nocturnal urination frequency is a common risk factor for bruises and fractures. Also, female sex and urge incontinence were the risk factors for bruises and fractures, respectively. OAB patients with urge incontinence would especially require aggressive intervention to prevent fractures during night-time voiding.

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Graf, R., S. Krishna et H. C. Heller. « Regulated nocturnal hypothermia induced in pigeons by food deprivation ». American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 256, n^o 3 (1 mars 1989) : R733—R738. http://dx.doi.org/10.1152/ajpregu.1989.256.3.r733.

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The daily body temperature (Tb) cycle of pigeons is altered by food deprivation in that Tb falls to lower and lower levels on consecutive nights after the onset of deprivation, whereas the Tb levels during corresponding days remain nearly unchanged. Manipulations of spinal cord temperature, a major feedback parameter in the avian thermoregulatory system, reveal that episodes of nocturnal hypothermia are regulated. The spinal cord threshold temperature for inducing increases in metabolic heat production falls to progressively lower levels each night and returns to normal euthermic levels during the day.

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Stevens, David, Brianna Jackson, Jayne Carberry, James McLoughlin, Chris Barr, Sutapa Mukherjee, Aaron Oh, R. Doug McEvoy, Maria Crotty et Andrew Vakulin. « The Impact of Obstructive Sleep Apnea on Balance, Gait, and Falls Risk : A Narrative Review of the Literature ». Journals of Gerontology : Series A 75, n^o 12 (10 février 2020) : 2450–60. http://dx.doi.org/10.1093/gerona/glaa014.

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Abstract Falls-related hospitalization and injury rates are steadily increasing globally due to a growth in the aging population, and the associated health problems that increase risk of falls. One such associated health problem is sleep disturbances and disorders. Recent cohort studies have shown that subjectively reported poor quality sleep is associated with an increased risk of falls. Obstructive sleep apnea (OSA) is a common sleep disorder characterized by the repetitive reductions, or cessation, of airflow. Some studies have shown that OSA impairs posture/balance and gait with nocturnal hypoxemia the likely main cause. Emerging evidence suggests that treating OSA by continuous positive airway pressure (CPAP) can improve gait, but no studies to date have examined the effect of CPAP on posture/balance. The overall control of balance relies on a complex interaction between several physiological functions including vestibular, muscle, visual, and cognitive functions. We postulate that OSA impacts balance by affecting these different systems to various degrees, with the nocturnal hypoxic burden likely playing an important role. Importantly, these impairments in balance/posture and possible falls risk may be alleviated by OSA treatment. Larger mechanistic studies are needed to properly elucidate how OSA affects falls risk and future large-scale randomized control trials are needed to determine the effectiveness of OSA treatment in reducing the risk of falls.

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Monaghan, T. F., A. S. Wagg, C. W. Agudelo, S. N. Rahman, K. P. Michelson, M. R. Epstein, K. Everaert, J. M. Lazar, J. P. Weiss et D. L. Bliwise. « 0822 Frail Older Men With Nocturia are Disproportionately Affected by Excess Nocturnal Urine Production ». Sleep 43, Supplement_1 (avril 2020) : A313. http://dx.doi.org/10.1093/sleep/zsaa056.818.

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Abstract Introduction Nocturia is a risk factor for falls and hip fractures in older adults. We determined whether the Frailty Index (FI), incorporating comorbidities, functional performance, and physical signs, was associated with nocturia frequency and/or overnight urine production. Methods We examined nightly (24-hour) voiding diaries (men ≥65 years) in an outpatient urologic clinic demonstrating ≥2 nocturnal voids (n=158). FI calculations followed Rockwood (CMAJ 2005;173:489-95). A total of 39 conditions were assessed. Three FI groups were established: Low (≤0.077) (n=59), Intermediate (>0.077 and <0.179) (n=58), and High (≥0.179) (n=41). We compared number of nocturnal voids (NV), nocturnal urine volume (NUV) (in mL), and 24-hr total urine volume (24-hr TUV) (in mL) across groups. Results NV did not differ by group (p=0.333) (median for all groups=3). However, NUV (916 [671-1419] vs. 690 [505-942] vs. 630 [500-1050] mL) differentiated the High, Medium and Low FI groups (p<0.001 via Kruskal-Wallis with Bonferroni pairwise adjustments), respectively. Similarly, 24-hr TUV differentiated the 3 groups (2200 [1800-2550] vs. 1620 [1259-2119] vs. 1650 [1390-2517] mL, p=0.005). Differences in NUV remained significant (p=0.006) after eliminating Diabetes Mellitus cases (n=44). However, differences did not persist for 24-hr TUV (p=0.180). Conclusion Higher NUV, but not 24-hr TUV, was a robust correlate of frailty in these older men. Accounting for diabetes did not diminish the effect. Although undiagnosed sleep apnea remains a possible cause, recent chronobiologic data (Monaghan et al, Age Aging, 2020, in press) suggest that nocturia in the aged is characterized by excess free water clearance early in the sleep period. This argues against solute-driven urine production (as might be expected in sleep apnea) in accounting for the effect. Nocturia may represent a conspicuous and important change in circadian rhythm of urine production occurring in old age. Support N/A

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Croce, Alessandro, Grzegorz Bilo, Martino F. Pengo, Alice Margherita Ornago, Alice Ricco, Giuseppe Bellelli et Gianfranco Parati. « CLINICAL SIGNIFICANCE OF NIGHTTIME BLOOD PRESSURE : EXPLORING THE ASSOCIATION OF NOCTURNAL HYPOTENSIVE PHENOTYPE AND HISTORY OF FALLS IN ELDERLY HYPERTENSIVE PATIENTS ». Journal of Hypertension 42, Suppl 1 (mai 2024) : e41. http://dx.doi.org/10.1097/01.hjh.0001019664.42434.7e.

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Objective: falls are a major health problem in elderly, approximately 28–35% of individuals aged > 65 years’ experience falls each year. Previous studies suggested that unexplained falls may mask a syncope or pseudo-syncope in almost 50% of cases, and that patients with reflex syncope have a higher prevalence of systolic blood pressure (SBP) drops on ambulatory blood pressure monitoring (ABPM), the so-called hypotensive phenotype. However, it is not clear whether hypotensive phenotype may be itself associated with falls. We investigate if hypotensive phenotype is associated with history of falls in elderly hypertensive. Design and method: a cross-sectional study that included treated hypertensive patients aged >=75 years evaluated at the Hypertension Center of Istituto Auxologico Italiano IRCCS in Milan. We excluded patients with a life expectancy of less than 6 months. All participants underwent ABPM. History of falls within the last year was recorded and multidimensional geriatric assessment to estimate frailty using Frailty accumulation index was performed. Daytime and night-time hypotensive phenotypes were defined as at least one SBP drops <90 mmHg on ABPM during daytime and night-time, respectively. The same analysis was repeated by considering cut-off of SBP <80 mmHg both during day and night-time. Results: we enrolled 105 patients, mainly females (n=80, 76%) with a mean age of 82 (± 4) years. In 74 (70%) patients day-time hypotensive phenotype was present at ABPM, while nighttime hypotensive phenotype was present in 24 of them (23%). Among participants 21 (20%) experienced a fall in the last 12 months; compared for age, sex, BMI, frailty index and BP patients with falls and not have no significant differences. Regardless of SBP cut-off, nocturnal hypotensive phenotype was associated with history of falls while daytime hypotensive phenotype was not. (Figure 1). Conclusions: In our study, nighttime but not daytime BP drops were associated with falls in treated hypertensive elderly patients. The mechanistic role of nighttime hypotensive phenotype and its association with syncope and falls will need to be evaluated in larger prospective studies to better clarify the utility of ABPM in falls prediction in elderly.

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Kario, Kazuomi, Thomas G. Pickering, Takefumi Matsuo, Satoshi Hoshide, Joseph E. Schwartz et Kazuyuki Shimada. « Stroke Prognosis and Abnormal Nocturnal Blood Pressure Falls in Older Hypertensives ». Hypertension 38, n^o 4 (octobre 2001) : 852–57. http://dx.doi.org/10.1161/hy1001.092640.

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Song, Xiaowei, et Benjamin Rusak. « Acute effects of light on body temperature and activity in Syrian hamsters : influence of circadian phase ». American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 278, n^o 5 (1 mai 2000) : R1369—R1380. http://dx.doi.org/10.1152/ajpregu.2000.278.5.r1369.

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Light exposure at night causes an acute increase in human body temperature, which normally falls during the night. This change is largely attributable to the suppression by light of the nocturnal rise in melatonin levels. Little is known, however, about the effects of light on body temperature in nocturnally active mammals in which the nightly peak in melatonin secretion coincides with the circadian phase of elevated, rather than decreased, body temperature. We investigated the effects of a 1-h exposure to light on body temperature and activity of Syrian hamsters, Mesocricetus auratus, at two phases during the night and at two phases during the projected day. Brain or abdominal temperature was recorded continuously using implanted radio transmitters while locomotor activity was monitored simultaneously using a passive infrared movement detector. Responses to light exposure were strongly circadian phase dependent; light during the night caused elevations in both brain and core body temperature, whereas light during the projected day did not. Temperature increases at night could not be attributed solely to activity increases at the onset of light pulses, indicating a contribution from nonbehavioral mechanisms of thermogenesis. These results provide the first evidence for circadian modulation of acute temperature responses to light in a nocturnal mammal.

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Ballard, R. D., M. C. Saathoff, D. K. Patel, P. L. Kelly et R. J. Martin. « Effect of sleep on nocturnal bronchoconstriction and ventilatory patterns in asthmatics ». Journal of Applied Physiology 67, n^o 1 (1 juillet 1989) : 243–49. http://dx.doi.org/10.1152/jappl.1989.67.1.243.

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To assess the effect of sleep on airflow resistance and patterns of ventilation in asthmatic patients with nocturnal worsening, 10 adult subjects (6 asthmatic patients with nocturnal worsening, 4 normal controls) were monitored overnight in the sleep laboratory on two separate occasions. During 1 night, subjects were allowed to sleep normally, whereas during the other night all sleep was prevented. The six asthmatic patients demonstrated progressive increases in lower airway resistance (Rla) on both nights, but the rate of increase was twofold greater (P less than 0.0001) during the sleep night compared with the sleep prevention night. However, overnight decrements in forced expired volume in 1 s (FEV1) were similar over the 2 nights. The asthmatic patients maintained their minute ventilation as Rla increased during sleep, demonstrating a stable tidal volume with a mild increase in respiratory frequency. We conclude that in asthmatic patients with nocturnal worsening 1) Rla increases and FEV1 falls overnight regardless of sleep state, 2) sleep enhances the observed overnight increases in Rla, and 3) sleep does not abolish compensatory ventilatory responses to spontaneously occurring bronchoconstriction.

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Thèses sur le sujet "Nocturnal falls"

Ibrahim, Ali. « Classification des troubles du sommeil par une modélisation informatique personnalisée pour la prévention des chutes nocturnes ». Electronic Thesis or Diss., Bourgogne Franche-Comté, 2024. http://www.theses.fr/2024UBFCA012.

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Le sommeil est une partie essentielle de la routine humaine, aussi vitale que la nourriture et l'eau. Un sommeil réparateur est lié à une amélioration du bien-être physique, cognitif et psychologique. À l'inverse, un sommeil de mauvaise qualité peut entraîner des déficiences cognitives et une détérioration générale de la santé physique, augmentant le risque de chutes. La surveillance du sommeil et la détection des chutes au lit sont donc des domaines de recherche cruciaux, ayant un impact significatif sur la santé humaine. Cette thèse se concentre sur la compréhension du sommeil et des chutes, et propose des dispositifs de surveillance du sommeil et de détection des chutes non intrusifs. Nous fournissons d'abord une compréhension du sommeil, y compris ses stades, l'importance de sa surveillance et les conséquences d'une mauvaise qualité de sommeil, incluant les chutes. Ensuite, nous présentons une compréhension des chutes chez les personnes âgées, leurs causes et leurs conséquences. Nous proposons également une classification des systèmes de surveillance du sommeil et des chutes basée sur le déploiement des capteurs, offrant aux scientifiques une meilleure compréhension et une base solide pour les systèmes existants.Nous proposons un dispositif portable compact qui peut être attaché aux vêtements de nuit pour mesurer l'accélération corporelle afin de surveiller le sommeil et détecter les chutes. Nous proposons également un nouveau système de nœud de capteur en temps réel, non portable et monté sur le contour du matelas, pour surveiller les activités de sommeil et détecter les chutes nocturnes. La performance des dispositifs est validée par des simulations, des expériences et une comparaison avec les dispositifs existants
Sleep is an important part of the human daily routine, as vital to survival as food and water. In fact, restorative sleep is closely linked to improved physical, cognitive, and psychological well-being. Conversely, poor or disordered sleep can result in cognitive and psychological impairments, as well as a decline in overall physical health, thereby increasing the risk of falls. To address these problems, sleep monitoring and detecting bed falls have thus become crucial areas of research, given their significant impact on human health and well-being. This thesis focuses on providing a foundational understanding of sleep and falls, in addition to proposing non-obtrusive sleep monitoring and fall detection devices. First, we provide a foundational understanding of sleep, including its stages, the significance of sleep monitoring, and the consequences of low sleep quality, including falls. Next, we present a basic understanding of falls in the elderly, their causes, and their consequences on the person as well as on the environment. We also propose a generic classification of sleep monitoring and fall-related systems based on their sensor deployment, aimed at offering scientists and engineers in this field a better understanding and providing a solid foundation for existing systems.Additionally, we propose a compact wearable device that can be attached to the person’s nightwear to measure body acceleration for sleep monitoring and fall detection. We also propose a novel real-time sensor node system that is non-wearable and mounted on the contour of the bed mattress to continuously monitor sleep activities and detect nocturnal falls. The performance of the proposed devices is validated through simulations, experiments, and comparison with existing devices

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Livres sur le sujet "Nocturnal falls"

Painter, Kristen, et Kira Nyte. The Princess Protects Her Huntsman : A Nocturne Falls Universe Story : Nocturne Falls Universe. CreateSpace Independent Publishing Platform, 2018.

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Martin, Graham R. Birds in the Dark : Complementary and Partial Information. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199694532.003.0006.

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Night-time poses exacting problems for vision, resolution inevitably falls and colour vision is not possible as light levels decrease to those of natural night time. Furthermore, light levels are highly variable depending upon whether there is moonlight, and night length changes dramatically in the annual cycle according to latitude. Few birds exploit the resources available at night. Those that do rely upon information received from vision complemented by information from other senses (hearing, olfaction, and touch), and upon highly specialized and restricted behaviours. However, many birds occasionally exploit night-time, e.g. during migration, arriving and departing from nests, and occasional night feeding. Some seabirds dive to such depths that they experience night-time light levels when foraging. Truly nocturnal species such as owls, kiwi, and oilbirds are highly sedentary, and this is essential to allow them to interpret correctly the partial information that is available to them.

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Kontis, Alethea. Besphinxed : A Nocturne Falls Universe Story. CreateSpace Independent Publishing Platform, 2018.

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Painter, Kristen. Nocturne Falls Short Story Collection #1. Kristen Painter, 2017.

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The Vampire's Accidental Wife (Nocturne Falls). Kristen Painter, 2017.

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The Vampire's Fake Fiancee (Nocturne Falls). CreateSpace Independent Publishing Platform, 2016.

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Painter, Kristen. The Shifter Romances the Writer (Nocturne Falls). Createspace Independent Publishing Platform, 2016.

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The Gargoyle Gets His Girl (Nocturne Falls). CreateSpace Independent Publishing Platform, 2015.

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The Werewolf Meets His Match (Nocturne Falls). CreateSpace Independent Publishing Platform, 2015.

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Roarke, Fiona. Aliens Actually : A Nocturne Falls Universe Collection. CreateSpace Independent Publishing Platform, 2017.

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Chapitres de livres sur le sujet "Nocturnal falls"

Stahl, Geoff. « When Night Fails ? Wellington’s Night-Time Culture in Flux ». Dans Nocturnes : Popular Music and the Night, 63–77. Cham : Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-99786-5_5.

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Walker, Matthew C. « Narcolepsy ». Dans Oxford Textbook of Medicine, sous la direction de Christopher Kennard, 5882–86. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198746690.003.0576.

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Narcolepsy with cataplexy is a specific syndrome of daytime sleepiness, disrupted nocturnal sleep, and episodes of sudden loss of muscle tone—provoked by the anticipation of emotions (in particular laughter)—leading to a tendency to fall, mouth opening, dysarthria or mutism, and facial muscle jerking. It is associated with loss of hypocretin (orexin) neurons in the hypothalamus, hypocretin concentrations in the cerebrospinal fluid below 110 pg/ml, and the HLA genotype DQ B1*0602. A less common form of narcolepsy without cataplexy probably has a different, as yet unknown, pathogenesis. Once established, narcolepsy is lifelong; spontaneous recovery does not occur. Symptomatic treatment—which is essential for school performance, work, driving ability, and quality of life—is with stimulant (e.g. amphetamine) and anticataplectic (e.g. clomipramine) drugs. More recently, sodium oxybate, an anaesthetic, has been used to induce deep sleep overnight, resulting in improvements in all symptoms.

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Actes de conférences sur le sujet "Nocturnal falls"

Fominykh, Andrew, Tov Elperin et Boris Krasovitov. « Scavenging of Soluble Gaseous Pollutants by Rain Droplets in the Atmosphere With Nocturnal Temperature Profile ». Dans 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22472.

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We analyze non-isothermal absorption of trace gases by the rain droplets with internal circulation which is caused by interfacial shear stresses. It is assumed that the temperature and concentration of soluble trace gases in the atmosphere varies in a vertical direction. The rate of scavenging of soluble trace gases by falling rain droplets is determined by solving heat and mass transfer equations. In the analysis we accounted for the accumulation of the absorbate in the bulk of the falling rain droplet. The problem is solved in the approximation of a thin concentration and temperature boundary layers in the droplet and in the surrounding air. We assumed that the bulk of a droplet, beyond the diffusion boundary layer, is completely mixed and concentration of the absorbate and temperature are homogeneous and time-dependent in the bulk. By combining the generalized similarity transformation method with Duhamel’s theorem, the system of transient conjugate equations of convective diffusion and energy conservation for absorbate transport in liquid and gaseous phases with time-dependent boundary conditions is reduced to a system of linear convolution Volterra integral equations of the second kind which is solved numerically. Calculations are performed using available experimental data on nocturnal temperature profiles in the atmosphere. It is shown than if concentration of a trace gas in the atmosphere is homogeneous and temperature in the atmosphere increases with altitude, droplet absorbs gas during all the period of its fall. Neglecting temperature inhomogenity in the atmosphere described by nocturnal temperature inversion leads to essential underestimation of the trace gas concentration in a droplet on the ground.

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Sassen, Kenneth. « Polarization Properties of Light Pillars : Brewster Angle Effects ». Dans Meteorological Optics. Washington, D.C. : Optica Publishing Group, 1986. http://dx.doi.org/10.1364/mo.1986.tha2.

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Nocturnal light pillar displays are not uncommon during conditions of very light snowfall when temperatures are well below freezing.1 Like the related reflection phenomenon of the sun pillar,2 light pillar occurrences demonstrate the presence of ice crystals oriented with their reflecting faces very nearly parallel to the ground. Assemblages of simple plate crystals, with their large basal faces, constitute the best scattering medium for these displays, provided that their sizes correspond to those which display stable fall attitudes.3 Sun and light pillars, however, have quite different structures as a result of the reflection geometries from light sources positioned essentially at infinity, and locally.4 Moreover, light pillars are perhaps unique among atmospheric optical displays in that they are anthropogenic and, since the observer is actually located within the cloud of crystals, it is a simple matter to study the nature of the particles causing the display.

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Grund, Christian J. « Coherent Doppler Lidar for Boundary Layer Wind Measurement Employing a Diode-Pumped Tm:Lu,YAG Laser ». Dans Coherent Laser Radar. Washington, D.C. : Optica Publishing Group, 1995. http://dx.doi.org/10.1364/clr.1995.mb2.

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Boundary layer research has been increasingly hampered by the lack of sensors that can economically provide accurate high spatial and temporal resolution wind measurements covering large atmospheric volumes. In particular, measurements of the turbulent fluctuations of the wind with better than 50 m spatial resolution covering volumes of a few km3/sec to distances of 10 km are needed to estimate weakly correlated turbulent quantities (e.g. momentum fluxes <u'w'>, <v'w'>). These measurements are also needed to test model parameterizations and to initialize model runs for Large Eddy Simulation (LES) models. These models have recently been used to provide detailed insights into fundamental boundary layer processes, particularly non-steady-state, transitional, and intermittent processes. Of particular interest to NOAA are the improvement of vertical resolution in the boundary layer entrainment zone, higher resolution observations of the nocturnal and baroclinic (neutral or shear-driven) boundary layers, day/night boundary layer transition processes, and observation of the ocean-atmosphere boundary layer. Other interests requiring new instrument capabilities are: the development of techniques for the direct measurement of fluxes of moisture, momentum, and chemical species, the measurement of vertical velocities and ice crystal fall speeds in cirrus clouds and the impact of shear on cloud morphology, the measurement of synoptic scale divergence and vorticity, and the behavior of complex terrain flows.

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