WorldWideScience

Sample records for stable nocturnal boundary

  1. Stable Boundary Layer Issues

    OpenAIRE

    Steeneveld, G.J.

    2012-01-01

    Understanding and prediction of the stable atmospheric boundary layer is a challenging task. Many physical processes are relevant in the stable boundary layer, i.e. turbulence, radiation, land surface coupling, orographic turbulent and gravity wave drag, and land surface heterogeneity. The development of robust stable boundary layer parameterizations for use in NWP and climate models is hampered by the multiplicity of processes and their unknown interactions. As a result, these models suffer ...

  2. Local characteristics of the nocturnal boundary layer in response to external pressure forcing

    NARCIS (Netherlands)

    van der Linden, S.J.A.; Baas, P.; van Hooft, J.A.; van Hooijdonk, I.G.S.; Bosveld, F.C.; van de Wiel, B.J.H.

    2017-01-01

    Geostrophic wind speed data, derived from pressure observations, are used in combination with tower measurements to investigate the nocturnal stable boundary layer at Cabauw (The Netherlands). Since the geostrophic wind speed is not directly influenced by local nocturnal stability, it may be

  3. Stable Boundary Layer Issues

    NARCIS (Netherlands)

    Steeneveld, G.J.

    2012-01-01

    Understanding and prediction of the stable atmospheric boundary layer is a challenging task. Many physical processes are relevant in the stable boundary layer, i.e. turbulence, radiation, land surface coupling, orographic turbulent and gravity wave drag, and land surface heterogeneity. The

  4. Fiber optic distributed temperature sensing for the determination of the nocturnal atmospheric boundary layer height

    Directory of Open Access Journals (Sweden)

    C. A. Keller

    2011-02-01

    Full Text Available A new method for measuring air temperature profiles in the atmospheric boundary layer at high spatial and temporal resolution is presented. The measurements are based on Raman scattering distributed temperature sensing (DTS with a fiber optic cable attached to a tethered balloon. These data were used to estimate the height of the stable nocturnal boundary layer. The experiment was successfully deployed during a two-day campaign in September 2009, providing evidence that DTS is well suited for this atmospheric application. Observed stable temperature profiles exhibit an exponential shape confirming similarity concepts of the temperature inversion close to the surface. The atmospheric mixing height (MH was estimated to vary between 5 m and 50 m as a result of the nocturnal boundary layer evolution. This value is in good agreement with the MH derived from concurrent Radon-222 (222Rn measurements and in previous studies.

  5. Surface influence upon vertical profiles in the nocturnal boundary layer

    Science.gov (United States)

    Garratt, J. R.

    1983-05-01

    Near-surface wind profiles in the nocturnal boundary layer, depth h, above relatively flat, tree-covered terrain are described in the context of the analysis of Garratt (1980) for the unstable atmospheric boundary layer. The observations at two sites imply a surface-based transition layer, of depth z *, within which the observed non-dimensional profiles Φ M 0 are a modified form of the inertial sub-layer relation Φ _M ( {{z L}} = ( {{{1 + 5_Z } L}} ) according to Φ _M^{{0}} ˜eq ( {{{1 + 5z} L}} )exp [ { - 0.7( {{{1 - z} z}_ * } )] , where z is height above the zero-plane displacement and L is the Monin-Obukhov length. At both sites the depth z * is significantly smaller than the appropriate neutral value ( z * N ) found from the previous analysis, as might be expected in the presence of a buoyant sink for turbulent kinetic energy.

  6. Modelling stable atmospheric boundary layers over snow

    NARCIS (Netherlands)

    Sterk, H.A.M.

    2015-01-01

    Thesis entitled:

    Modelling Stable Atmospheric Boundary Layers over Snow

    H.A.M. Sterk

    Wageningen, 29th of April, 2015

    Summary

    The emphasis of this thesis is on the understanding and forecasting of the Stable Boundary Layer (SBL) over snow-covered surfaces. SBLs

  7. Estimation of nocturnal CO2 and N2O soil emissions from changes in surface boundary layer mass storage

    Science.gov (United States)

    Grant, Richard H.; Omonode, Rex A.

    2018-04-01

    Annual budgets of greenhouse and other trace gases require knowledge of the emissions throughout the year. Unfortunately, emissions into the surface boundary layer during stable, calm nocturnal periods are not measurable using most micrometeorological methods due to non-stationarity and uncoupled flow. However, during nocturnal periods with very light winds, carbon dioxide (CO2) and nitrous oxide (N2O) frequently accumulate near the surface and this mass accumulation can be used to determine emissions. Gas concentrations were measured at four heights (one within and three above canopy) and turbulence was measured at three heights above a mature 2.5 m maize canopy from 23 July to 10 September 2015. Nocturnal CO2 and N2O fluxes from the canopy were determined using the accumulation of mass within a 6.3 m control volume and out the top of the control volume within the nocturnal surface boundary layer. Diffusive fluxes were estimated by flux gradient method. The total accumulative and diffusive fluxes during near-calm nights (friction velocities CO2 and 0.53 nmol m-2 s-1 N2O. Fluxes were also measured using chambers. Daily mean CO2 fluxes determined by the accumulation method were 90 to 130 % of those determined using soil chambers. Daily mean N2O fluxes determined by the accumulation method were 60 to 80 % of that determined using soil chambers. The better signal-to-noise ratios of the chamber method for CO2 over N2O, non-stationary flow, assumed Schmidt numbers, and anemometer tilt were likely contributing reasons for the differences in chambers versus accumulated nocturnal mass flux estimates. Near-surface N2O accumulative flux measurements in more homogeneous regions and with greater depth are needed to confirm the conclusion that mass accumulation can be effectively used to estimate soil emissions during nearly calm nights.

  8. Thermodynamic and Turbulence Characteristics of the Southern Great Plains Nocturnal Boundary Layer Under Differing Turbulent Regimes

    Science.gov (United States)

    Bonin, Timothy A.; Blumberg, William G.; Klein, Petra M.; Chilson, Phillip B.

    2015-12-01

    The nocturnal stable boundary layer (SBL) can generally be classified into the weakly stable boundary layer (wSBL) and very stable boundary layer (vSBL). Within the wSBL, turbulence is relatively continuous, whereas in the vSBL, turbulence is intermittent and not well characterized. Differentiating characteristics of each type of SBL are still unknown. Herein, thermodynamic and kinematic data collected by a suite of instruments in north central Oklahoma in autumn 2012 are analyzed to better understand both SBL regimes and their differentiating characteristics. Many low-level jets were observed during the experiment, as it took place near a climatological maximum. A threshold wind speed, above which bulk shear-generated turbulence develops, is found to exist up to 300 m. The threshold wind speed must also be exceeded at lower heights (down to the surface) in order for strong turbulence to develop. Composite profiles, which are normalized using low-level jet scaling, of potential temperature, wind speed, vertical velocity variance, and the third-order moment of vertical velocity (overline{w'^3}) are produced for weak and moderate/strong turbulence regimes, which exhibit features of the vSBL and wSBL, respectively. Within the wSBL, turbulence is generated at the surface and transported upward. In the vSBL, values of vertical velocity variance are small throughout the entire boundary layer, likely due to the fact that a strong surface inversion typically forms after sunset. The temperature profile tends to be approximately isothermal in the lowest portions of the wSBL, and it did not substantially change over the night. Within both types of SBL, stability in the residual layer tends to increase as the night progresses. It is thought that this stability increase is due to differential warm air advection, which frequently occurs in the southern Great Plains when southerly low-level jets and a typical north-south temperature gradient are present. Differential radiative

  9. Study of cross-spectra of velocity components and temperature series in a nocturnal boundary layer

    Science.gov (United States)

    Maqueda, Gregorio; Sastre, Mariano; Viñas, Carmen; Viana, Samuel; Yagüe, Carlos

    2010-05-01

    needed the correlation function of the time series analysed. Results will be regarding for different Richardson number and turbulent intensities, but always in nocturnal conditions, in order to evaluate the influence of the different turbulent and stratification degrees. References. - Blackman, R.B., and Tukey, J.,W., 1958: The measurement of power spectra from the point of view of communication engineering. Dover Publications, 190 pp. - Cuxart J, Yagüe C, Morales G, Terradellas E, Orbe J, Calvo J, Fernández A, Soler MR, Infante C, Buenestado P, Espinalt A, Joergensen HE, Rees JM, Vilá J, Redondo JM, Cantalapiedra IR and Conangla L (2000) Stable atmospheric boundary-layer experiment in Spain (SABLES98): a report. Boundary- Layer Meteorol 96:337-370. - Stull R. B. (1988), An Introduction to Boundary Layer Meteorology. Kluwer Academic Publisher. 666 pp. - Viana, S Yagüe, C and Maqueda, G (2009) Propagation and effects of a mesoscale gravity wave over a weaklysStratified nocturnal boundary layer during the SABLES2006 field campaign. Boundary-Layer Meteorol 133:165-188

  10. Radiation forcing by the atmospheric aerosols in the nocturnal boundary layer

    Science.gov (United States)

    Singh, D. K.; Ponnulakshami, V. K.; Mukund, V.; Subramanian, G.; Sreenivas, K. R.

    2013-05-01

    We have conducted experimental and theoretical studies on the radiation forcing due to suspended aerosols in the nocturnal boundary layer. We present radiative, conductive and convective equilibrium profile for different bottom boundaries where calculated Rayleigh number is higher than the critical Rayleigh number in laboratory conditions. The temperature profile can be fitted using an exponential distribution of aerosols concentration field. We also present the vertical temperature profiles in a nocturnal boundary in the presence of fog in the field. Our results show that during the presence of fog in the atmosphere, the ground temperature is greater than the dew-point temperature. The temperature profiles before and after the formation of fog are also observed to be different.

  11. Stable Low Cloud Phase II: Nocturnal Event Study

    Science.gov (United States)

    Bauman, William H., III; Barrett, Joe, III

    2007-01-01

    This report describes the work done by the Applied Meteorology Unit (AMU) in developing a database of nights that experienced rapid (formation in a stable atmosphere, resulting in ceilings at the Shuttle Landing Facility (TTS) that violated Space Shuttle Flight Rules (FR). This work is the second phase of a similar AMU task that examined the same phenomena during the day. In the first phase of this work, the meteorological conditions favoring the rapid formation of low ceilings include the presence of any inversion below 8000 ft, high relative humidity (RH) beneath the inversion and a clockwise turning of the winds from the surface to the middle troposphere (-15000 ft). The AMU compared and contrasted the atmospheric and thermodynamic conditions between nights with rapid low ceiling formation and nights with low ceilings resulting from other mechanisms. The AMU found that there was little to discern between the rapidly-forming ceiling nights and other low ceiling nights at TTS. When a rapid development occurred, the average RH below the inversions was 87% while non-events had an average RH of 79%. One key parameter appeared to be the vertical wind profile in the Cape Canaveral, FL radiosonde (XMR) sounding. Eighty-three percent of the rapid development events had veering winds with height from the surface to the middle troposphere (-15,000 ft) while 61% of the non-events had veering winds with height. Veering winds indicate a warm-advection regime, which supports large-scale rising motion and ultimately cloud formation in a moist environment. However, only six of the nights (out of 86 events examined) with low cloud ceilings had an occurrence of rapidly developing ceilings. Since only 7% rapid development events were observed in this dataset, it is likely that rapid low cloud development is not a common occurrence during the night, or at least not as common as during the day. In the AMU work on the daytime rapid low cloud development (Case and Wheeler 2005), nearly

  12. A stable boundary layer perspective on global temperature trends

    International Nuclear Information System (INIS)

    McNider, R T; Christy, J R; Biazar, A

    2010-01-01

    One of the most significant signals in the thermometer-observed temperature record since 1900 is the decrease in the diurnal temperature range over land, largely due to warming of the minimum temperatures. While some data sets have indicated this asymmetrical warming has been reduced since 1979, regional analyses (e.g. East Africa) indicate that the nocturnal warming continues at a pace greater than daytime temperatures. The cause for this night time warming in the observed temperatures has been attributed to a variety of causes. Climate models have in general not replicated the change in diurnal temperature range well. Here we would like to try to distinguish between warming in the nocturnal boundary layer due to a redistribution of heat and warming due to the accumulation of heat. The temperature at night at shelter height is a result of competition between thermal stability and mechanical shear. If stability wins then turbulence is suppressed and the cooling surface becomes cut-off from the warmer air aloft, which leads to sharp decay in surface air temperature. If shear wins, then turbulence is maintained and warmer air from aloft is continually mixed to the surface, which leads to significantly lower cooling rates and warmer temperatures. This warming occurs due to a redistribution of heat. As will be shown by techniques of nonlinear analysis the winner of the stability and shear contest can be very sensitive to changes in greenhouse gas forcing, surface roughness, cloudiness, and surface heat capacity (including soil moisture). Further, the minimum temperatures measured in the nocturnal boundary layer represent only a very shallow layer of the atmosphere which is usually only a few hundred meters thick. It is likely that the observed warming in minimum temperature, whether caused by additional greenhouse forcing or land use changes or other land surface dynamics, is reflecting a redistribution of heat by turbulence-not an accumulation of heat. Because minimum

  13. Carbon dioxide measurements in the nocturnal boundary layer over Amazonian forest

    Directory of Open Access Journals (Sweden)

    A. D. Culf

    1999-01-01

    Full Text Available Measurements of carbon dioxide concentration, temperature and windspeed were made in the nocturnal boundary layer over a tropical forest near Manaus, Brazil using a tethered balloon system. The measurements were made up to a maximum height of 300 m on ten consecutive nights in November 1995. Simultaneous surface flux and in-canopy concentration measurements were made at the surface close to the site. The observation period included several different types of conditions. Generally strong windshear and relatively weak temperature gradients prevented the formation of a strong capping inversion to the nocturnal boundary layer. On some nights, however, the inversion was sufficiently strong that the CO2 concentration at 100 m above the surface exceeded 400 ppm. The concentration within the canopy was largely controlled by the presence of an inversion very close to the canopy surface. The temperature and wind profiles are contrasted with conditions in Randônia, Brazil, where the windshear was found to be weaker and higher carbon dioxide concentrations were observed in the early morning. The difference in carbon dioxide concentrations in the nocturnal boundary layer between dusk and dawn is used to estimate the regional nighttime flux of carbon dioxide. The value obtained generally exceeds the measured surface flux and sometimes exceeds the sum of the surface flux and the in-canopy storage made at the tower site. The reasons for the discrepancy are not clear; either one of the methods is in error or the regional carbon dioxide budget differs significantly from the local budget measured at the tower site.

  14. Delay in convection in nocturnal boundary layer due to aerosol-induced cooling

    Science.gov (United States)

    Singh, Dhiraj Kumar; Ponnulakshmi, V. K.; Subramanian, G.; Sreenivas, K. R.

    2012-11-01

    Heat transfer processes in the nocturnal boundary layer (NBL) influence the surface energy budget, and play an important role in many micro-meteorological processes including the formation of inversion layers, radiation fog, and in the control of air-quality near the ground. Under calm clear-sky conditions, radiation dominates over other transport processes, and as a result, the air layers just above ground cool the fastest after sunset. This leads to an anomalous post-sunset temperature profile characterized by a minimum a few decimeters above ground (Lifted temperature minimum). We have designed a laboratory experimental setup to simulate LTM, involving an enclosed layer of ambient air, and wherein the boundary condition for radiation is decoupled from those for conduction and convection. The results from experiments involving both ambient and filtered air indicate that the high cooling rates observed are due to the presence of aerosols. Calculated Rayleigh number of LTM-type profiles is of the order 105-107 in the field and of order 103-105 in the laboratory. In the LTM region, there is convective motion when the Rayleigh number is greater than 104 rather than the critical Rayleigh number (Rac = 1709). The diameter of convection rolls is a function of height of minimum of LTM-type profiles. The results obtained should help in the parameterization of transport process in the nocturnal boundary layer, and highlight the need to accounting the effects of aerosols and ground emissivity in climate models.

  15. Plume meander and dispersion in a stable boundary layer

    Science.gov (United States)

    Hiscox, April L.; Miller, David R.; Nappo, Carmen J.

    2010-11-01

    Continuous lidar measurements of elevated plume dispersion and corresponding micrometeorology data are analyzed to establish the relationship between plume behavior and nocturnal boundary layer dynamics. Contrasting nights of data from the JORNADA field campaign in the New Mexico desert are analyzed. The aerosol lidar measurements were used to separate the plume diffusion (plume spread) from plume meander (displacement). Mutiresolution decomposition was used to separate the turbulence scale (90 s). Durations of turbulent kinetic energy stationarity and the wind steadiness were used to characterize the local scale and submesoscale turbulence. Plume meander, driven by submesoscale wind motions, was responsible for most of the total horizontal plume dispersion in weak and variable winds and strong stability. This proportion was reduced in high winds (i.e., >4 m s-1), weakly stable conditions but remained the dominant dispersion mechanism. The remainder of the plume dispersion in all cases was accounted for by internal spread of the plume, which is a small eddy diffusion process driven by turbulence. Turbulence stationarity and the wind steadiness are demonstrated to be closely related to plume diffusion and plume meander, respectively.

  16. Hyper-cooling in the nocturnal boundary layer: the Ramdas paradox

    International Nuclear Information System (INIS)

    Mukund, V; Ponnulakshmi, V K; Singh, D K; Subramanian, G; Sreenivas, K R

    2010-01-01

    Characterizing the interaction between turbulence and radiative processes is necessary for understanding the nocturnal atmospheric boundary layer. The subtle nature of the interaction is exemplified in a phenomenon called the 'Ramdas paradox' or the 'lifted temperature minimum' (LTM), involving preferential cooling near the Earth's surface. The prevailing explanation for the LTM (the VSN model, Vasudeva Murthy et al (1993 Phil. Trans. R. Soc. A 344 183-206)) invokes radiative exchange in a homogeneous nocturnal atmosphere to predict a large cooling of the near-surface air layers. It is shown here that the cooling predicted by the VSN model is spurious, and that any preferential cooling can occur only in a heterogeneous atmosphere. The underlying error is fundamental, and occurs to varying degrees in a wide class of radiative models, in a flux-emissivity formulation, the VSN model being a prominent example. We, for the first time, propose the correct flux-emissivity formulation that eliminates spurious cooling. Results from field observations and laboratory experiments presented here, however, show that the near-surface radiative cooling is real; near-surface cooling rates can be orders of magnitude higher than values elsewhere in the boundary layer. The results presented include the dependence of the LTM on turbulence, the surface emissivity and the thermal inertia of the ground. It is proposed that aerosols provide the heterogeneity needed for the preferential cooling mechanism. Turbulence, by determining the aerosol concentration distribution over the relevant length scales, plays a key role in the phenomenon. Experimental evidence is presented to support this hypothesis.

  17. Hyper-cooling in the nocturnal boundary layer: the Ramdas paradox

    Energy Technology Data Exchange (ETDEWEB)

    Mukund, V; Ponnulakshmi, V K; Singh, D K; Subramanian, G; Sreenivas, K R, E-mail: krs@jncasr.ac.in [Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore (India)

    2010-12-15

    Characterizing the interaction between turbulence and radiative processes is necessary for understanding the nocturnal atmospheric boundary layer. The subtle nature of the interaction is exemplified in a phenomenon called the 'Ramdas paradox' or the 'lifted temperature minimum' (LTM), involving preferential cooling near the Earth's surface. The prevailing explanation for the LTM (the VSN model, Vasudeva Murthy et al (1993 Phil. Trans. R. Soc. A 344 183-206)) invokes radiative exchange in a homogeneous nocturnal atmosphere to predict a large cooling of the near-surface air layers. It is shown here that the cooling predicted by the VSN model is spurious, and that any preferential cooling can occur only in a heterogeneous atmosphere. The underlying error is fundamental, and occurs to varying degrees in a wide class of radiative models, in a flux-emissivity formulation, the VSN model being a prominent example. We, for the first time, propose the correct flux-emissivity formulation that eliminates spurious cooling. Results from field observations and laboratory experiments presented here, however, show that the near-surface radiative cooling is real; near-surface cooling rates can be orders of magnitude higher than values elsewhere in the boundary layer. The results presented include the dependence of the LTM on turbulence, the surface emissivity and the thermal inertia of the ground. It is proposed that aerosols provide the heterogeneity needed for the preferential cooling mechanism. Turbulence, by determining the aerosol concentration distribution over the relevant length scales, plays a key role in the phenomenon. Experimental evidence is presented to support this hypothesis.

  18. Hyper-cooling in the nocturnal boundary layer: the Ramdas paradox

    Science.gov (United States)

    Mukund, V.; Ponnulakshmi, V. K.; Singh, D. K.; Subramanian, G.; Sreenivas, K. R.

    2010-12-01

    Characterizing the interaction between turbulence and radiative processes is necessary for understanding the nocturnal atmospheric boundary layer. The subtle nature of the interaction is exemplified in a phenomenon called the 'Ramdas paradox' or the 'lifted temperature minimum' (LTM), involving preferential cooling near the Earth's surface. The prevailing explanation for the LTM (the VSN model, Vasudeva Murthy et al (1993 Phil. Trans. R. Soc. A 344 183-206)) invokes radiative exchange in a homogeneous nocturnal atmosphere to predict a large cooling of the near-surface air layers. It is shown here that the cooling predicted by the VSN model is spurious, and that any preferential cooling can occur only in a heterogeneous atmosphere. The underlying error is fundamental, and occurs to varying degrees in a wide class of radiative models, in a flux-emissivity formulation, the VSN model being a prominent example. We, for the first time, propose the correct flux-emissivity formulation that eliminates spurious cooling. Results from field observations and laboratory experiments presented here, however, show that the near-surface radiative cooling is real; near-surface cooling rates can be orders of magnitude higher than values elsewhere in the boundary layer. The results presented include the dependence of the LTM on turbulence, the surface emissivity and the thermal inertia of the ground. It is proposed that aerosols provide the heterogeneity needed for the preferential cooling mechanism. Turbulence, by determining the aerosol concentration distribution over the relevant length scales, plays a key role in the phenomenon. Experimental evidence is presented to support this hypothesis.

  19. Nocturnal sleep, daytime sleepiness, and quality of life in stable patients on hemodialysis

    Directory of Open Access Journals (Sweden)

    Bliwise Donald L

    2003-11-01

    Full Text Available Abstract Background Although considerable progress has been made in the treatment of chronic kidney disease, compromised quality of life continues to be a significant problem for patients receiving hemodialysis (HD. However, in spite of the high prevalence of sleep complaints and disorders in this population, the relationship between these problems and quality of life remains to be well characterized. Thus, we studied a sample of stable HD patients to explore relationships between quality of life and both subjective and objective measures of nocturnal sleep and daytime sleepiness Methods The sample included forty-six HD patients, 24 men and 22 women, with a mean age of 51.6 (10.8 years. Subjects underwent one night of polysomnography followed the next morning by a Multiple Sleep Latency Test (MSLT, an objective measure of daytime sleepiness. Subjects also completed: 1 a brief nocturnal sleep questionnaire; 2 the Epworth Sleepiness Scale; and, 3 the Quality of Life Index (QLI, Dialysis Version which provides an overall QLI score and four subscale scores for Health & Functioning (H&F, Social & Economic (S&E, Psychological & Spiritual (P&S, and Family (F. (The range of scores is 0 to 30 with higher scores indicating better quality of life. Results The mean (standard deviation; SD of the overall QLI was 22.8 (4.0. The mean (SD of the four subscales were as follows: H&F – 21.1 (4.7; S&E – 22.0 (4.8; P&S – 24.5 (4.4; and, F – 26.8 (3.5. H&F (rs = -0.326, p = 0.013 and F (rs = -0.248, p = 0.048 subscale scores were negatively correlated with periodic limb movement index but not other polysomnographic measures. The H&F subscale score were positively correlated with nocturnal sleep latency (rs = 0.248, p = 0.048 while the H&F (rs = 0.278, p = 0.030 and total QLI (rs = 0.263, p = 0.038 scores were positively associated with MSLT scores. Both of these latter findings indicate that higher life quality is associated with lower sleepiness levels. ESS

  20. Methane distributions and transports in the nocturnal boundary layer at a rural station

    Science.gov (United States)

    Schäfer, Klaus; Zeeman, Matthias; Brosy, Caroline; Münkel, Christoph; Fersch, Benjamin; Mauder, Matthias; Emeis, Stefan

    2016-10-01

    To investigate the methane distributions and transports, the role of related atmospheric processes by determination of vertical profiles of wind, turbulence, temperature and humidity as well as nocturnal boundary layer (NBL) height and the quantification of methane emissions at local and plot scale the so-called ScaleX-campaign was performed in a pre-alpine observatory in Southern Germany from 01 June until 31 July 2015. The following measurements from the ground up to the free troposphere were performed: layering of the atmosphere by a ceilometer (Vaisala CL51); temperature, wind, turbulence profiles from 50 m up to 500 m by a Radio-Acoustic Sounding System (RASS, Metek GmbH); temperature, humidity profiles in situ by a hexacopter; methane farm emissions by two open-path laser spectrometers (Boreal GasFinder2); methane concentrations in situ (Los Gatos DLT-100) with tubes in 0.3 m agl and 5 sampling heads; and methane soil emissions by a big chamber (10 m length, 2.60 m width, up to 0.61 m height) with a plastic cover. The methane concentrations near the surface show a daily variation with a maximum and a frequent double-peak structure during night-time. Analysis of the variation of the nocturnal methane concentration together with the hexacopter and RASS data indicates that the first peak in the nocturnal methane concentration is probably due to local cooling and stabilization which keeps the methane emissions from the soil near the ground. The second peak seems to be due to advection of methane-enriched air which had formed in the environment of the nearby farm yards. These dairy farm emissions were determined by up-wind and down-wind open-path concentration measurements, turbulence data from an EC station nearby and Backward Lagrangian Simulation (WindTrax software). The methane fluxes at plot scale (big chamber) are characterized by emissions at water saturated grassland patches, by an exponential decrease of these emissions during grassland drying, and by an

  1. Characteristics of nocturnal coastal boundary layer in Ahtopol based on averaged SODAR profiles

    Science.gov (United States)

    Barantiev, Damyan; Batchvarova, Ekaterina; Novitzky, Mikhail

    2014-05-01

    The ground-based remote sensing instruments allow studying the wind regime and the turbulent characteristics of the atmosphere with height, achieving new knowledge and solving practical problems, such as air quality assessments, mesoscale models evaluation with high resolution data, characterization of the exchange processes between the surface and the atmosphere, the climate comfort conditions and the risk for extreme events, etc. Very important parameter in such studies is the height of the atmospheric boundary layer. Acoustic remote sensing data of the coastal atmospheric boundary layer were explored based on over 4-years continuous measurements at the meteorological observatory of Ahtopol (Bulgarian Southern Black Sea Coast) under Bulgarian - Russian scientific agreement. Profiles of 12 parameters from a mid-range acoustic sounding instrument type SCINTEC MFAS are derived and averaged up to about 600 m according filtering based on wind direction (land or sea type of night fowls). From the whole investigated period of 1454 days with 10-minute resolution SODAR data 2296 profiles represented night marine air masses and 1975 profiles represented the night flow from land during the months May to September. Graphics of averaged profiles of 12 SODAR output parameters with different availability of data in height are analyzed for both cases. A marine boundary-layer height of about 300 m is identified in the profiles of standard deviation of vertical wind speed (σw), Turbulent Kinetic Energy (TKE) and eddy dissipation rate (EDR). A nocturnal boundary-layer height of about 420 m was identified from the profiles of the same parameters under flows from land condition. In addition, the Buoyancy Production (BP= σw3/z) profiles were calculated from the standard deviation of the vertical wind speed and the height z above ground.

  2. A Mesoscale Model-Based Climatography of Nocturnal Boundary-Layer Characteristics over the Complex Terrain of North-Western Utah.

    Science.gov (United States)

    Serafin, Stefano; De Wekker, Stephan F J; Knievel, Jason C

    Nocturnal boundary-layer phenomena in regions of complex topography are extremely diverse and respond to a multiplicity of forcing factors, acting primarily at the mesoscale and microscale. The interaction between different physical processes, e.g., drainage promoted by near-surface cooling and ambient flow over topography in a statically stable environment, may give rise to special flow patterns, uncommon over flat terrain. Here we present a climatography of boundary-layer flows, based on a 2-year archive of simulations from a high-resolution operational mesoscale weather modelling system, 4DWX. The geographical context is Dugway Proving Ground, in north-western Utah, USA, target area of the field campaigns of the MATERHORN (Mountain Terrain Atmospheric Modeling and Observations Program) project. The comparison between model fields and available observations in 2012-2014 shows that the 4DWX model system provides a realistic representation of wind speed and direction in the area, at least in an average sense. Regions displaying strong spatial gradients in the field variables, thought to be responsible for enhanced nocturnal mixing, are typically located in transition areas from mountain sidewalls to adjacent plains. A key dynamical process in this respect is the separation of dynamically accelerated downslope flows from the surface.

  3. Experiments on aerosol-induced cooling in the nocturnal boundary layer

    Science.gov (United States)

    Sreenivas, K.; Singh, D. K.; Vk, P.; Mukund, V.; Subramanian, G.

    2012-12-01

    In the nocturnal boundary layer (NBL), under calm & clear-sky conditions, radiation is the principal mode of heat transfer & it determines the temperature distribution close to the ground. Radiative processes thus influence the surface energy budget, & play a decisive role in many micro-meteorological processes including the formation of radiation-fog & inversion layer. Here, we report hyper-cooling of air layers close to the ground that has a radiative origin. Resulting vertical temperature distribution has an anomalous profile with an elevated minimum few decimetres above the ground (known as Lifted Temperature Minimum; LTM). Even though the first observation of this type of profile dates back to 1930s, its origin has not been explained till recently. We report field experiments to elucidate effects of emissivity and other physical properties of the ground on the LTM profile. Field observations clearly indicate that LTM-profiles are observed as a rule in the lowest meter of the NBL. We also demonstrate that the air-layer near the ground, rather than the ground itself, leads the post sunset cooling. This fact changes the very nature of the sensible heat-flux boundary condition. A laboratory experimental setup has been developed that can reproduce LTM. Lab-experiments demonstrate that the high cooling rates observed in the field experiments arise from the presence of aerosols & the intensity of cooling is proportional to aerosol concentration (Fig-1). We have also captured penetrative convection cells in the field experiments (Fig-2). Results presented here thus help in parameterizing transport processes in the NBL.

  4. Impulse propagation in the nocturnal boundary layer: analysis of the geometric component.

    Science.gov (United States)

    Blom, Philip; Waxler, Roger

    2012-05-01

    On clear dry nights over flat land, a temperature inversion and stable nocturnal wind jet lead to an acoustic duct in the lowest few hundred meters of the atmosphere. An impulsive signal propagating in such a duct is received at long ranges from the source as an extended wave train consisting of a series of weakly dispersed distinct arrivals followed by a strongly dispersed low-frequency tail. The leading distinct arrivals have been previously shown to be well modeled by geometric acoustics. In this paper, the geometric acoustics approximation for the leading arrivals is investigated. Using the solutions of the eikonal and transport equations, travel times, amplitudes, and caustic structures of the distinct arrivals have been determined. The time delay between and relative amplitudes of the direct-refracted and single ground reflection arrivals have been investigated as parameters for an inversion scheme. A two parameter quadratic approximation to the effective sound speed profile has been fit and found to be in strong agreement with meteorological measurements from the time of propagation.

  5. Validation of farm-scale methane emissions using nocturnal boundary layer budgets

    Directory of Open Access Journals (Sweden)

    J. Stieger

    2015-12-01

    Full Text Available This study provides the first experimental validation of Swiss agricultural methane emission estimates at the farm scale. We measured CH4 concentrations at a Swiss farmstead during two intensive field campaigns in August 2011 and July 2012 to (1 quantify the source strength of livestock methane emissions using a tethered balloon system and (2 to validate inventory emission estimates via nocturnal boundary layer (NBL budgets. Field measurements were performed at a distance of 150 m from the nearest farm buildings with a tethered balloon system in combination with gradient measurements at eight heights on a 10 m tower to better resolve the near-surface concentrations. Vertical profiles of air temperature, relative humidity, CH4 concentration, wind speed, and wind direction showed that the NBL was strongly influenced by local transport processes and by the valley wind system. Methane concentrations showed a pronounced time course, with highest concentrations in the second half of the night. NBL budget flux estimates were obtained via a time–space kriging approach. Main uncertainties of NBL budget flux estimates were associated with nonstationary atmospheric conditions and the estimate of the inversion height zi (top of volume integration. The mean NBL budget fluxes of 1.60 ± 0.31 μg CH4 m-2 s-1 (1.40 ± 0.50 and 1.66 ± 0.20 μg CH4 m-2 s-1 in 2011 and 2012 respectively were in good agreement with local inventory estimates based on current livestock number and default emission factors, with 1.29 ± 0.47 and 1.74 ± 0.63 μg CH4 m-2 s-1 for 2011 and 2012 respectively. This indicates that emission factors used for the national inventory reports are adequate, and we conclude that the NBL budget approach is a useful tool to validate emission inventory estimates.

  6. Validation of farm-scale methane emissions using nocturnal boundary layer budgets

    Science.gov (United States)

    Stieger, J.; Bamberger, I.; Buchmann, N.; Eugster, W.

    2015-12-01

    This study provides the first experimental validation of Swiss agricultural methane emission estimates at the farm scale. We measured CH4 concentrations at a Swiss farmstead during two intensive field campaigns in August 2011 and July 2012 to (1) quantify the source strength of livestock methane emissions using a tethered balloon system and (2) to validate inventory emission estimates via nocturnal boundary layer (NBL) budgets. Field measurements were performed at a distance of 150 m from the nearest farm buildings with a tethered balloon system in combination with gradient measurements at eight heights on a 10 m tower to better resolve the near-surface concentrations. Vertical profiles of air temperature, relative humidity, CH4 concentration, wind speed, and wind direction showed that the NBL was strongly influenced by local transport processes and by the valley wind system. Methane concentrations showed a pronounced time course, with highest concentrations in the second half of the night. NBL budget flux estimates were obtained via a time-space kriging approach. Main uncertainties of NBL budget flux estimates were associated with nonstationary atmospheric conditions and the estimate of the inversion height zi (top of volume integration). The mean NBL budget fluxes of 1.60 ± 0.31 μg CH4 m-2 s-1 (1.40 ± 0.50 and 1.66 ± 0.20 μg CH4 m-2 s-1 in 2011 and 2012 respectively) were in good agreement with local inventory estimates based on current livestock number and default emission factors, with 1.29 ± 0.47 and 1.74 ± 0.63 μg CH4 m-2 s-1 for 2011 and 2012 respectively. This indicates that emission factors used for the national inventory reports are adequate, and we conclude that the NBL budget approach is a useful tool to validate emission inventory estimates.

  7. Nitrogen Oxides in the Nocturnal Boundary Layer: Chemistry of Nitrous Acid (HONO) and the Nitrate Radical (N03)

    Energy Technology Data Exchange (ETDEWEB)

    Jochen Stutz

    2005-05-24

    Summary Chemical processes occurring at night in the lowest part of the urban atmosphere, the so called nocturnal boundary layer (NBL), can influence the composition of the atmosphere during the night as well as the following day. They may impact the budgets of some of the most important pollutants, such as ozone and nitrogen oxides, as well as influence size and composition of particular matter. Few studies have thus far concentrated on the nocturnal chemistry of the urban NBL, most likely due to the strong influence of vertical transport and mixing, which requires the measurement of trace gas profiles instead of simple point observations. Motivated by our lack of observations and understanding of nocturnal chemistry, the focus of this project was the study of the vertical distribution of trace gases and the altitude dependence of nocturnal chemistry under polluted conditions through field observations and modeling studies. The analysis of three field experiments (TEXAQS, Houston, 2000; Phoenix Sunrise Ozone Experiment, 2001; NAPOX, Boston, 2002), two of which were performed in this project, showed that ozone concentrations typically increase with height in the lowest 150m, while NO2 typically decreases. NO3, the dominant nocturnal radical species, showed much higher concentrations in the upper part of the NBL, and was often not present at the ground. With the help of a one-dimensional chemical transport model, developed in this project, we found that the interaction of ground emissions of NOx and hydrocarbons, together with their vertical transport, is responsible for the vertical profiles. The dominant chemical reactions influencing ozone, NO2 and NO3 are the reaction of ozone and NO3 with freshly emitted NO. Sensitivity studies with our model showed that the magnitude of the trace gas gradients depend both on the emission rates and the vertical stability of the NBL. Observations and model analysis clearly show that nocturnal chemistry in urban areas is altitude

  8. Boundary Between Stable and Unstable Regimes of Accretion

    Directory of Open Access Journals (Sweden)

    Blinova A. A.

    2014-01-01

    Full Text Available We investigated the boundary between stable and unstable regimes of accretion and its dependence on different parameters. Simulations were performed using a “cubed sphere" code with high grid resolution (244 grid points in the azimuthal direction, which is twice as high as that used in our earlier studies. We chose a very low viscosity value, with alpha-parameter α=0.02. We observed from the simulations that the boundary strongly depends on the ratio between magnetospheric radius rm (where the magnetic stress in the magnetosphere matches the matter stress in the disk and corotation radius rcor (where the Keplerian velocity in the disk is equal to the angular velocity of the star. For a small misalignment angle of the dipole field, Θ = 5°, accretion is unstable if rcor/rm> 1.35, and is stable otherwise. In cases of a larger misalignment angle of the dipole, Θ = 20°, instability occurs at slightly larger values, rcor/rm> 1.41

  9. Comments on deriving the equilibrium height of the stable boundary layer

    NARCIS (Netherlands)

    Steeneveld, G.J.; Wiel, van de B.J.H.; Holtslag, A.A.M.

    2007-01-01

    Recently, the equilibrium height of the stable boundary layer received much attention in a series of papers by Zilitinkevich and co-workers. In these studies the stable boundary-layer height is derived in terms of inverse interpolation of different boundary-layer height scales, each representing a

  10. Modelling the artic stable boundary layer and its coupling to the surface

    NARCIS (Netherlands)

    Steeneveld, G.J.; Wiel, van de B.J.H.; Holtslag, A.A.M.

    2006-01-01

    The impact of coupling the atmosphere to the surface energy balance is examined for the stable boundary layer, as an extension of the first GABLS (GEWEX Atmospheric Boundary-Layer Study) one-dimensional model intercomparison. This coupling is of major importance for the stable boundary-layer

  11. From Near-Neutral to Strongly Stratified: Adequately Modelling the Clear-Sky Nocturnal Boundary Layer at Cabauw.

    Science.gov (United States)

    Baas, P; van de Wiel, B J H; van der Linden, S J A; Bosveld, F C

    2018-01-01

    The performance of an atmospheric single-column model (SCM) is studied systematically for stably-stratified conditions. To this end, 11 years (2005-2015) of daily SCM simulations were compared to observations from the Cabauw observatory, The Netherlands. Each individual clear-sky night was classified in terms of the ambient geostrophic wind speed with a [Formula: see text] bin-width. Nights with overcast conditions were filtered out by selecting only those nights with an average net radiation of less than [Formula: see text]. A similar procedure was applied to the observational dataset. A comparison of observed and modelled ensemble-averaged profiles of wind speed and potential temperature and time series of turbulent fluxes showed that the model represents the dynamics of the nocturnal boundary layer (NBL) at Cabauw very well for a broad range of mechanical forcing conditions. No obvious difference in model performance was found between near-neutral and strongly-stratified conditions. Furthermore, observed NBL regime transitions are represented in a natural way. The reference model version performs much better than a model version that applies excessive vertical mixing as is done in several (global) operational models. Model sensitivity runs showed that for weak-wind conditions the inversion strength depends much more on details of the land-atmosphere coupling than on the turbulent mixing. The presented results indicate that in principle the physical parametrizations of large-scale atmospheric models are sufficiently equipped for modelling stably-stratified conditions for a wide range of forcing conditions.

  12. From Near-Neutral to Strongly Stratified: Adequately Modelling the Clear-Sky Nocturnal Boundary Layer at Cabauw

    Science.gov (United States)

    Baas, P.; van de Wiel, B. J. H.; van der Linden, S. J. A.; Bosveld, F. C.

    2018-02-01

    The performance of an atmospheric single-column model (SCM) is studied systematically for stably-stratified conditions. To this end, 11 years (2005-2015) of daily SCM simulations were compared to observations from the Cabauw observatory, The Netherlands. Each individual clear-sky night was classified in terms of the ambient geostrophic wind speed with a 1 m s^{-1} bin-width. Nights with overcast conditions were filtered out by selecting only those nights with an average net radiation of less than - 30 W m^{-2}. A similar procedure was applied to the observational dataset. A comparison of observed and modelled ensemble-averaged profiles of wind speed and potential temperature and time series of turbulent fluxes showed that the model represents the dynamics of the nocturnal boundary layer (NBL) at Cabauw very well for a broad range of mechanical forcing conditions. No obvious difference in model performance was found between near-neutral and strongly-stratified conditions. Furthermore, observed NBL regime transitions are represented in a natural way. The reference model version performs much better than a model version that applies excessive vertical mixing as is done in several (global) operational models. Model sensitivity runs showed that for weak-wind conditions the inversion strength depends much more on details of the land-atmosphere coupling than on the turbulent mixing. The presented results indicate that in principle the physical parametrizations of large-scale atmospheric models are sufficiently equipped for modelling stably-stratified conditions for a wide range of forcing conditions.

  13. On Stable Wall Boundary Conditions for the Hermite Discretization of the Linearised Boltzmann Equation

    Science.gov (United States)

    Sarna, Neeraj; Torrilhon, Manuel

    2018-01-01

    We define certain criteria, using the characteristic decomposition of the boundary conditions and energy estimates, which a set of stable boundary conditions for a linear initial boundary value problem, involving a symmetric hyperbolic system, must satisfy. We first use these stability criteria to show the instability of the Maxwell boundary conditions proposed by Grad (Commun Pure Appl Math 2(4):331-407, 1949). We then recognise a special block structure of the moment equations which arises due to the recursion relations and the orthogonality of the Hermite polynomials; the block structure will help us in formulating stable boundary conditions for an arbitrary order Hermite discretization of the Boltzmann equation. The formulation of stable boundary conditions relies upon an Onsager matrix which will be constructed such that the newly proposed boundary conditions stay close to the Maxwell boundary conditions at least in the lower order moments.

  14. Stable Atmospheric Boundary Layer Experiment in Spain (SABLES 98) : a report

    NARCIS (Netherlands)

    Cuxart, J.; Yague, C.; Morales, G.; Terradelles, E.; Orbe, J.; Calvo, J.; Vilu-Guerau, de J.; Soler, M.R.; Infante, C.; Buenestado, P.; Espinalt, A.; Jorgensem, H.E.

    2000-01-01

    This paper describes the Stable Atmospheric Boundary Layer Experiment in Spain (SABLES 98), which took place over the northern Spanish plateau comprising relatively flat grassland, in September 1998. The main objectives of the campaign were to study the properties of the mid-latitude stable boundary

  15. Current Challenges in Understanding and Forecasting Stable Boundary Layers over Land and Ice

    Directory of Open Access Journals (Sweden)

    Gert-Jan eSteeneveld

    2014-10-01

    Full Text Available Understanding and prediction of the stable atmospheric boundary layer is challenging. Many physical processes come into play in the stable boundary layer, i.e. turbulence, radiation, land surface coupling and heterogeneity, orographic turbulent and gravity wave drag. The development of robust stable boundary-layer parameterizations for weather and climate models is difficult because of the multiplicity of processes and their complex interactions. As a result, these models suffer from biases in key variables, such as the 2-m temperature, boundary-layer depth and wind speed. This short paper briefly summarizes the state-of-the-art of stable boundary layer research, and highlights physical processes that received only limited attention so far, in particular orographically-induced gravity wave drag, longwave radiation divergence, and the land-atmosphere coupling over a snow-covered surface. Finally, a conceptual framework with relevant processes and particularly their interactions is proposed.

  16. Direct numerical simulation of stable and unstable turbulent thermal boundary layers

    International Nuclear Information System (INIS)

    Hattori, Hirofumi; Houra, Tomoya; Nagano, Yasutaka

    2007-01-01

    This paper presents direct numerical simulations (DNS) of stable and unstable turbulent thermal boundary layers. Since a buoyancy-affected boundary layer is often encountered in an urban environmental space where stable and unstable stratifications exist, exploring a buoyancy-affected boundary layer is very important to know the transport phenomena of the flow in an urban space. Although actual observation may qualitatively provide the characteristics of these flows, the relevant quantitative turbulent quantities are very difficult to measure. Thus, in order to quantitatively investigate a buoyancy-affected boundary layer in detail, we have here carried out for the first time time- and space-developing DNS of slightly stable and unstable turbulent thermal boundary layers. The DNS results show the quantitative turbulent statistics and structures of stable and unstable thermal boundary layers, in which the characteristic transport phenomena of thermally stratified boundary layers are demonstrated by indicating the budgets of turbulent shear stress and turbulent heat flux. Even though the input of buoyant force is not large, the influence of buoyancy is clearly revealed in both stable and unstable turbulent boundary layers. In particular, it is found that both stable and unstable thermal stratifications caused by the weak buoyant force remarkably alter the structure of near-wall turbulence

  17. Effective search for stable segregation configurations at grain boundaries with data-mining techniques

    Science.gov (United States)

    Kiyohara, Shin; Mizoguchi, Teruyasu

    2018-03-01

    Grain boundary segregation of dopants plays a crucial role in materials properties. To investigate the dopant segregation behavior at the grain boundary, an enormous number of combinations have to be considered in the segregation of multiple dopants at the complex grain boundary structures. Here, two data mining techniques, the random-forests regression and the genetic algorithm, were applied to determine stable segregation sites at grain boundaries efficiently. Using the random-forests method, a predictive model was constructed from 2% of the segregation configurations and it has been shown that this model could determine the stable segregation configurations. Furthermore, the genetic algorithm also successfully determined the most stable segregation configuration with great efficiency. We demonstrate that these approaches are quite effective to investigate the dopant segregation behaviors at grain boundaries.

  18. Entropy Stable Wall Boundary Conditions for the Three-Dimensional Compressible Navier-Stokes Equations

    Science.gov (United States)

    Parsani, Matteo; Carpenter, Mark H.; Nielsen, Eric J.

    2015-01-01

    Non-linear entropy stability and a summation-by-parts framework are used to derive entropy stable wall boundary conditions for the three-dimensional compressible Navier-Stokes equations. A semi-discrete entropy estimate for the entire domain is achieved when the new boundary conditions are coupled with an entropy stable discrete interior operator. The data at the boundary are weakly imposed using a penalty flux approach and a simultaneous-approximation-term penalty technique. Although discontinuous spectral collocation operators on unstructured grids are used herein for the purpose of demonstrating their robustness and efficacy, the new boundary conditions are compatible with any diagonal norm summation-by-parts spatial operator, including finite element, finite difference, finite volume, discontinuous Galerkin, and flux reconstruction/correction procedure via reconstruction schemes. The proposed boundary treatment is tested for three-dimensional subsonic and supersonic flows. The numerical computations corroborate the non-linear stability (entropy stability) and accuracy of the boundary conditions.

  19. Entropy Stable Wall Boundary Conditions for the Compressible Navier-Stokes Equations

    Science.gov (United States)

    Parsani, Matteo; Carpenter, Mark H.; Nielsen, Eric J.

    2014-01-01

    Non-linear entropy stability and a summation-by-parts framework are used to derive entropy stable wall boundary conditions for the compressible Navier-Stokes equations. A semi-discrete entropy estimate for the entire domain is achieved when the new boundary conditions are coupled with an entropy stable discrete interior operator. The data at the boundary are weakly imposed using a penalty flux approach and a simultaneous-approximation-term penalty technique. Although discontinuous spectral collocation operators are used herein for the purpose of demonstrating their robustness and efficacy, the new boundary conditions are compatible with any diagonal norm summation-by-parts spatial operator, including finite element, finite volume, finite difference, discontinuous Galerkin, and flux reconstruction schemes. The proposed boundary treatment is tested for three-dimensional subsonic and supersonic flows. The numerical computations corroborate the non-linear stability (entropy stability) and accuracy of the boundary conditions.

  20. First observations of elevated ducts associated with intermittent turbulence in the stable boundary layer over Bosten Lake, China

    Science.gov (United States)

    Sun, Zheng; Ning, Hui; Song, Shihui; Yan, Dongmei

    2016-10-01

    Nocturnal radiative cooling is a main driver for atmospheric duct formation. Within this atmospheric process, the impacts of intermittent turbulence on ducting have seldom been studied. In this paper, we reported two confusing ducting events observed in the early morning in August 2014 over Bosten Lake, China, when a stable boundary layer (SBL) still survived, by using tethered high-resolution GPS radiosondes. Elevated ducts with strong humidity inversions were observed during the balloon ascents but were absent during observations made upon the balloon descents several minutes later. This phenomenon was initially hypothesized to be attributable to turbulence motions in the SBL, and the connection between the turbulence event and the radar duct was examined by the statistical Thorpe method. Turbulence patches were detected from the ascent profiles but not from the descent profiles. The possible reasons for the duct formation and elimination were discussed in detail. The turbulent transport of moisture in the SBL and the advection due to airflows coming from the lake are the most probable reasons for duct formation. In one case, the downward transport of moisture by turbulence mixing within a Kelvin-Helmholtz billow at the top of the low-level jet resulted in duct elimination. In another case, the passage of density currents originating from the lake may have caused the elimination of the duct. Few studies have attempted to associate intermittent turbulence with radar ducts; thus, this work represents a pioneering study into the connection between turbulent events and atmospheric ducts in a SBL.

  1. A stable penalty method for the compressible Navier-Stokes equations: I. Open boundary conditions

    DEFF Research Database (Denmark)

    Hesthaven, Jan; Gottlieb, D.

    1996-01-01

    The purpose of this paper is to present asymptotically stable open boundary conditions for the numerical approximation of the compressible Navier-Stokes equations in three spatial dimensions. The treatment uses the conservation form of the Navier-Stokes equations and utilizes linearization...

  2. Intermittent turbulence and oscillations in the stable boundary layer over land

    NARCIS (Netherlands)

    Wiel, van de B.

    2002-01-01

    As the title of this thesis indicates, our main subject of interest is: "Intermittent turbulence and oscillation in the stable boundary layer over land". As such, this theme connects the different chapters. Here, intermittent turbulence is defined as a sequence of events were 'burst' of

  3. Stable boundary-layer regimes at dome C, Antarctica : observation and analysis

    NARCIS (Netherlands)

    Vignon, E.; van de Wiel, B.J.H.; van Hooijdonk, I.G.S.; Genthon, C.; van der Linden, S.J.A.; van Hooft, J.A.; Baas, P.; Maurel, W.; Traullé, O.; Casasanta, G.

    2017-01-01

    Investigation of meteorological measurements along a 45 m tower at Dome C on the high East Antarctic Plateau revealed two distinct stable boundary layer (SBL) regimes at this location. The first regime is characterized by strong winds and continuous turbulence. It results in full vertical coupling

  4. A Formula for the Depth of the Stable Boundary layer: Evaluation and Dimensional Analysis

    NARCIS (Netherlands)

    Steeneveld, G.J.; Wiel, van de B.J.H.; Holtslag, A.A.M.

    2006-01-01

    The height (h) of the stable boundary layer (SBL) is of major importance to understand the relevant processes that govern the SBL development. The SBL depth is the layer in which turbulence transport takes place, and thus governs the vertical structure of the lower atmosphere. Furthermore, release

  5. Local Similarity in the Stable Boundary Layer and Mixing-Length Approaches : Consistency of Concepts

    NARCIS (Netherlands)

    Van de Wiel, B.J.H.; Moene, A.F.; De Ronde, W.H.; Jonker, H.J.J.

    2008-01-01

    In stably stratified flows vertical movement of eddies is limited by the fact that kinetic energy is converted into potential energy, leading to a buoyancy displacement scale z B . Our new mixing-length concept for turbulent transport in the stable boundary layer follows a rigid-wall analogy, in the

  6. Local similarity in the stable boundary layer and mixing-length approaches: consistency of concepts

    NARCIS (Netherlands)

    Wiel, van de B.J.H.; Moene, A.F.; Ronde, W.H.; Jonker, H.J.J.

    2008-01-01

    In stably stratified flows vertical movement of eddies is limited by the fact that kinetic energy is converted into potential energy, leading to a buoyancy displacement scale z B . Our new mixing-length concept for turbulent transport in the stable boundary layer follows a rigid-wall analogy, in the

  7. Local similarity in the stable boundary layer and mixing-length approaches : consistency of concepts

    NARCIS (Netherlands)

    Wiel, van de B.J.H.; Moene, A.F.; Ronde, de W.H.; Jonker, H.J.J.

    2008-01-01

    In stably stratified flows vertical movement of eddies is limited by the fact that kinetic energy is converted into potential energy, leading to a buoyancy displacement scale zB. Our new mixing-length concept for turbulent transport in the stable boundary layer follows a rigid-wall analogy, in the

  8. The Impact of High-Resolution Sea Surface Temperatures on the Simulated Nocturnal Florida Marine Boundary Layer

    Science.gov (United States)

    LaCasse, Katherine M.; Splitt, Michael E.; Lazarus, Steven M.; Lapenta, William M.

    2008-01-01

    High- and low-resolution sea surface temperature (SST) analysis products are used to initialize the Weather Research and Forecasting (WRF) Model for May 2004 for short-term forecasts over Florida and surrounding waters. Initial and boundary conditions for the simulations were provided by a combination of observations, large-scale model output, and analysis products. The impact of using a 1-km Moderate Resolution Imaging Spectroradiometer (MODIS) SST composite on subsequent evolution of the marine atmospheric boundary layer (MABL) is assessed through simulation comparisons and limited validation. Model results are presented for individual simulations, as well as for aggregates of easterly- and westerly-dominated low-level flows. The simulation comparisons show that the use of MODIS SST composites results in enhanced convergence zones. earlier and more intense horizontal convective rolls. and an increase in precipitation as well as a change in precipitation location. Validation of 10-m winds with buoys shows a slight improvement in wind speed. The most significant results of this study are that 1) vertical wind stress divergence and pressure gradient accelerations across the Florida Current region vary in importance as a function of flow direction and stability and 2) the warmer Florida Current in the MODIS product transports heat vertically and downwind of this heat source, modifying the thermal structure and the MABL wind field primarily through pressure gradient adjustments.

  9. Nocturnal Boundary-Layer Phenomena Observed at a Complex Site During the Perdigão Experiment

    Science.gov (United States)

    Bell, T.; Klein, P. M.; Smith, E.; Gebauer, J.; Turner, D. D.

    2017-12-01

    The Perdigão Field Experiment set out to study atmospheric flows in complex terrain and to collect a high-quality dataset for the validation of meso- and micro-scale models. An Intensive Observation Period (IOP) was conducted from May 1, 2017 through June 15, 2017 where a multitude of instruments were deployed in and around two nearly parallel ridges. The Collaborative Lower Atmospheric Mobile Profiling System (CLAMPS) was deployed and operated in the valley between the ridges. The CLAMPS facility, which was developed as a joint effort between the School of Meteorology at OU and NOAA's National Severe Storms Laboratory (NSSL), takes advantage of a microwave radiometer (MWR), an atmospheric emitted radiance interferometer (AERI), and a scanning doppler Lidar to profile the boundary layer with a high temporal and spatial resolution. Optimized Lidar scanning strategies and joint retrievals for the MWR and ARI data provide detailed information about the wind, turbulence and thermodynamic structure from the surface up to 1000 m AGL on most nights; sometimes the max height is even higher. Over the course of the IOP, CLAMPS observed many different phenomena. During some nights, when stronger background prevailed and was directed perpendicular to the valley, waves were observed at the ridges and in the valley. At the same time, radiational cooling led to drainage flows in the valley, particularly during nights when the mesoscale forcing was weak. At first, CLAMPS profile observations and data collected with radiosondes released at a near-by site are compared to assess the data quality. The radiosonde observations are also being used to document and classify the upper-level flow during the IOP. Additionally, CLAMPS data from a few selected nights will be presented and analyzed in terms of turbulence and its impact on mixing inside and above the valley. June 1-2 represents a good base-state case. Winds at ridge height were generally less than 5ms-1 after 0Z and valley flows

  10. Camada limite noturna sobre área de pastagem na Amazônia Nocturnal boundary layer over an Amazonian pasture area

    Directory of Open Access Journals (Sweden)

    Theomar Trindade de Araújo Tiburtino Neves

    2011-12-01

    Full Text Available Neste trabalho foram discutidas as características da Camada Limite Noturna (CLN e o regime turbulento predominante, durante a campanha DRY-to-WET, período de transição seco para chuvoso (setembro a novembro do experimento RaCCI/LBA 2002. Foi utilizado um sítio de pastagem (Faz. Nossa Senhora Aparecida - 10°45'S, 62°21'W, 290 m na região de Ouro Preto D'Oeste - RO, com medidas de radiossonda (RS, balão cativo (BC, estação meteorológica automática (EMA e de equipamento de sensoriamento remoto (SODAR. A determinação do regime turbulento ocorreu através do parâmetro de Monin-Obukhov. As alturas da CLN obtidas por várias técnicas (RS, BC e SODAR, que variaram de 156,3 ± 57,9 m ao pôr-do-sol a 301,0 ± 124,5 m no início da manhã do dia seguinte, apresentaram semelhança com resultados já obtidos na estação seca da mesma região. Entretanto a característica da estabilidade atmosférica foi similar a situações obtidas na estação úmida. Ou seja, durante o período de transição entre as estações seca e chuvosa, a atmosfera não fica totalmente estabelecida apresentando características tanto da estação seca (por exemplo os valores da altura da CLN como da úmida (características da estabilidade.This paper discuss the characteristics of the nocturnal boundary layer (NBL and the prevailing turbulent regime during the campaign DRY-to-WET, dry to wet season transition period (September-November of RaCCI/LBA 2002. Measurements of radiosonde (RS, tethered balloon (TB, automatic weather station (AWS and SODAR (remote sensing device were made over the pasture site (Faz. Nossa Senhora Aparecida - 10 ° 45'S, 62 ° 21'W, 290 m in the region of Ouro Preto D'Oeste - RO. The turbulent flow regime was determined using the Monin-Obukhov parameter. The NBL heights (RS, BC and SODAR, ranging from 156.3 ± 57.9 m at sunset up to 301.0 ± 124.5 m on the early morning of the next day, showed similarity with data already obtained during

  11. A self-affine multi-fractal wave turbulence discrimination method using data from single point fast response sensors in a nocturnal atmospheric boundary layer

    OpenAIRE

    Kamada, Ray; Decaria, Alex Joseph

    1992-01-01

    We present DA, a self-affine, multi-fractal which may become the first routine wave/turbulence discriminant for time series data. Using nocturnal atmospheric data, we show the advantages of D A over self-similar fractals and standard turbulence measures such as FFTs, Richardson number, Brunt-Vaisala frequency, buoyancy length scale, variances, turbulent kinetic energy, and phase averaging. DA also shows promise in resolving "wave-break" events. Since it uses local basis functions, DA may be...

  12. Nocturnal continuous glucose monitoring

    DEFF Research Database (Denmark)

    Bay, Christiane; Kristensen, Peter Lommer; Pedersen-Bjergaard, Ulrik

    2013-01-01

    Abstract Background: A reliable method to detect biochemical nocturnal hypoglycemia is highly needed, especially in patients with recurrent severe hypoglycemia. We evaluated reliability of nocturnal continuous glucose monitoring (CGM) in patients with type 1 diabetes at high risk of severe...

  13. Influence of precipitating light elements on stable stratification below the core/mantle boundary

    Science.gov (United States)

    O'Rourke, J. G.; Stevenson, D. J.

    2017-12-01

    Stable stratification below the core/mantle boundary is often invoked to explain anomalously low seismic velocities in this region. Diffusion of light elements like oxygen or, more slowly, silicon could create a stabilizing chemical gradient in the outermost core. Heat flow less than that conducted along the adiabatic gradient may also produce thermal stratification. However, reconciling either origin with the apparent longevity (>3.45 billion years) of Earth's magnetic field remains difficult. Sub-isentropic heat flow would not drive a dynamo by thermal convection before the nucleation of the inner core, which likely occurred less than one billion years ago and did not instantly change the heat flow. Moreover, an oxygen-enriched layer below the core/mantle boundary—the source of thermal buoyancy—could establish double-diffusive convection where motion in the bulk fluid is suppressed below a slowly advancing interface. Here we present new models that explain both stable stratification and a long-lived dynamo by considering ongoing precipitation of magnesium oxide and/or silicon dioxide from the core. Lithophile elements may partition into iron alloys under extreme pressure and temperature during Earth's formation, especially after giant impacts. Modest core/mantle heat flow then drives compositional convection—regardless of thermal conductivity—since their solubility is strongly temperature-dependent. Our models begin with bulk abundances for the mantle and core determined by the redox conditions during accretion. We then track equilibration between the core and a primordial basal magma ocean followed by downward diffusion of light elements. Precipitation begins at a depth that is most sensitive to temperature and oxygen abundance and then creates feedbacks with the radial thermal and chemical profiles. Successful models feature a stable layer with low seismic velocity (which mandates multi-component evolution since a single light element typically

  14. Stable High-Performance Perovskite Solar Cells via Grain Boundary Passivation.

    Science.gov (United States)

    Niu, Tianqi; Lu, Jing; Munir, Rahim; Li, Jianbo; Barrit, Dounya; Zhang, Xu; Hu, Hanlin; Yang, Zhou; Amassian, Aram; Zhao, Kui; Liu, Shengzhong Frank

    2018-04-01

    The trap states at grain boundaries (GBs) within polycrystalline perovskite films deteriorate their optoelectronic properties, making GB engineering particularly important for stable high-performance optoelectronic devices. It is demonstrated that trap states within bulk films can be effectively passivated by semiconducting molecules with Lewis acid or base functional groups. The perovskite crystallization kinetics are studied using in situ synchrotron-based grazing-incidence X-ray scattering to explore the film formation mechanism. A model of the passivation mechanism is proposed to understand how the molecules simultaneously passivate the Pb-I antisite defects and vacancies created by under-coordinated Pb atoms. In addition, it also explains how the energy offset between the semiconducting molecules and the perovskite influences trap states and intergrain carrier transport. The superior optoelectronic properties are attained by optimizing the molecular passivation treatments. These benefits are translated into significant enhancements of the power conversion efficiencies to 19.3%, as well as improved environmental and thermal stability of solar cells. The passivated devices without encapsulation degrade only by ≈13% after 40 d of exposure in 50% relative humidity at room temperature, and only ≈10% after 24 h at 80 °C in controlled environment. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Stable High-Performance Perovskite Solar Cells via Grain Boundary Passivation

    KAUST Repository

    Niu, Tianqi

    2018-03-12

    The trap states at grain boundaries (GBs) within polycrystalline perovskite films deteriorate their optoelectronic properties, making GB engineering particularly important for stable high-performance optoelectronic devices. It is demonstrated that trap states within bulk films can be effectively passivated by semiconducting molecules with Lewis acid or base functional groups. The perovskite crystallization kinetics are studied using in situ synchrotron-based grazing-incidence X-ray scattering to explore the film formation mechanism. A model of the passivation mechanism is proposed to understand how the molecules simultaneously passivate the Pb-I antisite defects and vacancies created by under-coordinated Pb atoms. In addition, it also explains how the energy offset between the semiconducting molecules and the perovskite influences trap states and intergrain carrier transport. The superior optoelectronic properties are attained by optimizing the molecular passivation treatments. These benefits are translated into significant enhancements of the power conversion efficiencies to 19.3%, as well as improved environmental and thermal stability of solar cells. The passivated devices without encapsulation degrade only by ≈13% after 40 d of exposure in 50% relative humidity at room temperature, and only ≈10% after 24 h at 80 °C in controlled environment.

  16. Discrete Green's Theorem, Green's Functions and Stable Radiative FDTD Boundary Conditions

    NARCIS (Netherlands)

    Arnold, J.M.; Hon, de B.P.

    2007-01-01

    We propose a radiative boundary condition for the discrete-grid formulation of Helmholtz’ equation, based on rational approximation in the frequency domain of a Green’s function for the discretised system. This boundary condition is free from instabilities.

  17. Carbon and oxygen stable isotope and trace element studies in speleothems and across the J-K boundary, Central Italy

    International Nuclear Information System (INIS)

    Kudielka, G.

    2001-07-01

    Frasassi Cave have always been lower in d18O and higher in d13C compared to Soreq Cave. This indicates lower temperatures and a higher portion of C4 type vegetation in the Frasassi area compared to Israel. The agreement of the two records demonstrates that calcite deposits in caves are ideal recorders to global climatic changes. Investigation of the Jurassic/Cretaceous Boundary in Central Italy, the Jurassic/Cretaceous (J-K) boundary has not been satisfactory defined yet. Among others, various boundary definitions have been proposed at the Bosso River Gorge in the Marche region of Northern Italy: by calcareous nanofossils (at 329 m), calpionellids (at 334.1 m) and magnetostratigraphy (at 318 m). A large impact structure near Morokweng in South Africa was recently radiometrically dated to 144.7±1.9 Ma, which is indistinguishable from the stratigraphic age of the J-K boundary (144.2±2.6 Ma). A possible link between the impact event and the J-K boundary might be manifested in form of stratigraphic and geochemical features across the boundary, such as sudden stable-isotope shifts and spheroidal element anomalies. A set of 110 samples spanning about 40 m across the boundary was investigated for stable isotope ratios, and trace element content was determined in the corresponding decarbonated samples. d13C and d18O hardly vary but show a significant decrease at 333.5 m, which is close to the boundary-definition based upon calpionellids (at 334.1 m). Trace element abundances of Fe, Co, Ni, and Cr show remarkable enrichments very close to the boundary as defined by calcareous nanofossils (at 329 m). Another minor anomaly is noticeable at 333.5 m for Ir and Cr. Thus, the present data might be interpreted to hint - not to confirm - the presence of an impactoclastic layer at the Bosso River Gorge. (author)

  18. Areal-averaged trace gas emission rates from long-range open-path measurements in stable boundary layer conditions

    Directory of Open Access Journals (Sweden)

    K. Schäfer

    2012-07-01

    Full Text Available Measurements of land-surface emission rates of greenhouse and other gases at large spatial scales (10 000 m2 are needed to assess the spatial distribution of emissions. This can be readily done using spatial-integrating micro-meteorological methods like flux-gradient methods which were evaluated for determining land-surface emission rates of trace gases under stable boundary layers. Non-intrusive path-integrating measurements are utilized. Successful application of a flux-gradient method requires confidence in the gradients of trace gas concentration and wind, and in the applicability of boundary-layer turbulence theory; consequently the procedures to qualify measurements that can be used to determine the flux is critical. While there is relatively high confidence in flux measurements made under unstable atmospheres with mean winds greater than 1 m s−1, there is greater uncertainty in flux measurements made under free convective or stable conditions. The study of N2O emissions of flat grassland and NH3 emissions from a cattle lagoon involves quality-assured determinations of fluxes under low wind, stable or night-time atmospheric conditions when the continuous "steady-state" turbulence of the surface boundary layer breaks down and the layer has intermittent turbulence. Results indicate that following the Monin-Obukhov similarity theory (MOST flux-gradient methods that assume a log-linear profile of the wind speed and concentration gradient incorrectly determine vertical profiles and thus flux in the stable boundary layer. An alternative approach is considered on the basis of turbulent diffusivity, i.e. the measured friction velocity as well as height gradients of horizontal wind speeds and concentrations without MOST correction for stability. It is shown that this is the most accurate of the flux-gradient methods under stable conditions.

  19. Pseudo steady states of HONO measured in the nocturnal marine boundary layer: a conceptual model for HONO formation on aqueous surfaces

    Directory of Open Access Journals (Sweden)

    P. Wojtal

    2011-04-01

    Full Text Available A complete understanding of the formation mechanism of nitrous acid (HONO in the ambient atmosphere is complicated by a lack of understanding of processes occurring when aqueous water is present. We report nocturnal measurements of HONO, SO2 and NO2 by differential optical absorption spectroscopy over the ocean surface in a polluted marine environment. In this aqueous environment, we observed reproducible pseudo steady states (PSS of HONO every night, that are fully formed shortly after sunset, much faster than seen in urban environments. During the PSS period, HONO is constant with time, independent of air mass source and independent of the concentration of NO2. The independence of HONO on the concentration of NO2 implies a 0° order formation process, likely on a saturated surface, with reversible partitioning of HONO to the gas phase, through vaporization and deposition to the surface. We observed median HONO/NO2 ratios starting at 0.13 at the beginning of the PSS period (with an apparent lower bound of 0.03, rising to median levels of ~0.30 at the end of the PSS period (with an upper bound >1.0. The implication of these numbers is that they suggest a common surface mechanism of HONO formation on terrestrial and aqueous surfaces, with an increase in the HONO/NO2 ratio with the amount of water available at the surface. The levels of HONO during the nocturnal PSS period are positively correlated with temperature, consistent with a partitioning of HONO from the surface to the gas phase with an apparent enthalpy of vaporization of ΔHSNL (HONO=55.5±5.4 kJ mol−1. The formation mechanism on aqueous surfaces is independent of relative humidity (RH, despite observation of a negative HONO-RH correlation. A conceptual model for HONO formation on ambient aqueous surfaces is presented, with the main elements being the presence of a surface nanolayer (SNL

  20. A Study of stable Atmospheric Boundary Layer over highveld South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Luhunga, P; Djolov, G [University of Pretoria (South Africa); Esau, I, E-mail: george.djolov@up.ac.z

    2010-08-15

    The study is part of the South African - Norwegian Programme for Research and Co-operation Phase II 'Analysis and Possibility for Control of Atmospheric Boundary Layer Processes to Facilitate Adaptation to Environmental Changes'. The research strategy of the project is based on 4 legged approach. 1) Application and further development of contemporary atmospheric boundary layer theory. 2) Use of modeling based on large eddy simulation techniques. 3) Experimental investigation of turbulent fluxes. 4) Training and developing academics capable of dealing with the present and new challenges. The paper presents some preliminary results on the micrometeorological variability of the basic meteorological parameters and turbulent fluxes.

  1. A Study of stable Atmospheric Boundary Layer over highveld South Africa

    International Nuclear Information System (INIS)

    Luhunga, P; Djolov, G; Esau, I

    2010-01-01

    The study is part of the South African - Norwegian Programme for Research and Co-operation Phase II 'Analysis and Possibility for Control of Atmospheric Boundary Layer Processes to Facilitate Adaptation to Environmental Changes'. The research strategy of the project is based on 4 legged approach. 1) Application and further development of contemporary atmospheric boundary layer theory. 2) Use of modeling based on large eddy simulation techniques. 3) Experimental investigation of turbulent fluxes. 4) Training and developing academics capable of dealing with the present and new challenges. The paper presents some preliminary results on the micrometeorological variability of the basic meteorological parameters and turbulent fluxes.

  2. Large-eddy simulation of stable atmospheric boundary layers to develop better turbulence closures for climate and weather models

    Science.gov (United States)

    Bou-Zeid, Elie; Huang, Jing; Golaz, Jean-Christophe

    2011-11-01

    A disconnect remains between our improved physical understanding of boundary layers stabilized by buoyancy and how we parameterize them in coarse atmospheric models. Most operational climate models require excessive turbulence mixing in such conditions to prevent decoupling of the atmospheric component from the land component, but the performance of such a model is unlikely to be satisfactory under weakly and moderately stable conditions. Using Large-eddy simulation, we revisit some of the basic challenges in parameterizing stable atmospheric boundary layers: eddy-viscosity closure is found to be more reliable due to an improved alignment of vertical Reynolds stresses and mean strains under stable conditions, but the dependence of the magnitude of the eddy viscosity on stability is not well represented by several models tested here. Thus, we propose a new closure that reproduces the different stability regimes better. Subsequently, tests of this model in the GFDL's single-column model (SCM) are found to yield good agreement with LES results in idealized steady-stability cases, as well as in cases with gradual and sharp changes of stability with time.

  3. Stable atmospheric boundary-layer experiment in Spain (SABLES 98): A report

    DEFF Research Database (Denmark)

    Cuxart, J.; Yague, C.; Morales, G.

    2000-01-01

    boundary layer (SBL). Instrumentation deployed on two meteorological masts (of heights 10 m and 100 m) included five sonic anemometers, 15 thermocouples, five cup anemometers and three propeller anemometers, humidity sensors and radiometers. A Sensitron mini-sodar and a tethered balloon were also operated...

  4. Quantifying the local influence at a tall tower site in nocturnal conditions

    Energy Technology Data Exchange (ETDEWEB)

    Werth, David; Buckley, Robert; Zhang, Gengsheng; Kurzeja, Robert; Leclerc, Monique; Duarte, Henrique; Parker, Matthew; Watson, Thomas

    2015-10-17

    The influence of the local terrestrial environment on nocturnal atmospheric CO2 measurements at a 329-m television transmitter tower (and a component of a CO2 monitoring network) was estimated with a tracer release experiment and a subsequent simulation of the releases. This was done to characterize the vertical transport of emissions from the surface to the uppermost tower level and how it is affected by atmospheric stability. The tracer release experiment was conducted over two nights in May of 2009 near the Department of Energy’s Savannah River Site (SRS) in South Carolina. Tracer was released on two contrasting nights—slightly stable and moderately stable—from several upwind surface locations. Measurements at the 329-m level on both nights indicate that tracer was able to mix vertically within a relatively short (~24 km) distance, implying that nocturnal stable conditions do not necessarily prevent vertical dispersion in the boundary layer and that CO2 measurements at the tower are at least partly influenced by nearby emissions. A simulation of the tracer release is used to calculate the tower footprint on the two nights to estimate the degree to which the local domain affects the tower readings. The effect of the nocturnal boundary layer on the area sampled by the tower can be seen clearly, as the footprints were affected by changes in stability. The contribution of local sources to the measurements at the tower was minimal, however, suggesting that nocturnal concentrations at upper levels are contributed mostly by regional sources.

  5. Extended Stable Boundary of LCL-Filtered Grid-Connected Inverter Based on An Improved Grid-Voltage Feedforward Control

    DEFF Research Database (Denmark)

    Lu, Minghui; Xin, Zhen; Wang, Xiongfei

    2016-01-01

    should be designed under one-sixth of sampling frequency. However, the low resonance frequency leads to a comparatively large filter inductance or/and capacitance. To extend the stable boundary to the region above fs/6, this paper proposes a novel voltage feedforward scheme for the LCL-filtered inverter....... Theoretical analysis is then provided to validate its feasibility and stability. Compared to other widely used active damping strategies, no extra sensors are needed because the filter capacitor voltage, which is used for voltage feedforward control, is also sampled for phase-locked loop in this paper...

  6. Determination of stable shapes of a thin liquid metal layer using a boundary integral method

    Energy Technology Data Exchange (ETDEWEB)

    Hinaje, M [Groupe de Recherche en Electrotechnique et Electronique de Nancy, 2 avenue de la Foret de Haye, 54516 Vandoeuvre-les-Nancy (France); Vinsard, G [Laboratoire d' Energetique et de Mecanique Theorique et Appliquee, 2 avenue de la Foret de Haye, 54516 Vandoeuvre-les-Nancy (France); Dufour, S [Groupe de Recherche en Electrotechnique et Electronique de Nancy, 2 avenue de la Foret de Haye, 54516 Vandoeuvre-les-Nancy (France)

    2006-03-21

    This paper deals with a thin liquid metal layer submitted to an ac magnetic field. Experimentally, we have noticed that even if the system (inductor+liquid metal) is axisymmetric, when an ac magnetic field is applied the symmetry is broken. The observed deformations of the liquid metal are in three dimensions. Therefore, our aim is to investigate this deformation using a numerical method as boundary element method in three dimensions.

  7. Determination of stable shapes of a thin liquid metal layer using a boundary integral method

    International Nuclear Information System (INIS)

    Hinaje, M; Vinsard, G; Dufour, S

    2006-01-01

    This paper deals with a thin liquid metal layer submitted to an ac magnetic field. Experimentally, we have noticed that even if the system (inductor+liquid metal) is axisymmetric, when an ac magnetic field is applied the symmetry is broken. The observed deformations of the liquid metal are in three dimensions. Therefore, our aim is to investigate this deformation using a numerical method as boundary element method in three dimensions

  8. Paroxysmal nocturnal hemoglobinuria (PNH)

    Science.gov (United States)

    ... help slow the breakdown of red blood cells. Blood transfusions may be needed. Supplemental iron and folic acid ... is no known way to prevent this disorder. Alternative Names PNH Images Blood cells References Brodsky RA. Proxymal nocturnal hemoglobinuria. In: ...

  9. New Polymorph of Fe3O4 Stable at Core-Mantle Boundary Conditions

    Science.gov (United States)

    Greenberg, E.; Prakapenka, V. B.

    2017-12-01

    Magnetite Fe3O4 (and its high-pressure polymorphs) is one of the most studied iron bearing minerals. One reason for the interest in magnetite is that it contains both Fe2+ and Fe3+, which is especially important for understanding the physical and chemical properties of Earth's deep interior. Early studies on magnetite debated the nature of the structural phase transition at 35 GPa [1-4]. This high-pressure structure was shown to be of the CaTi2O4-type [5], but with Fe3+ occupying multiple sites. Furthermore, at pressures above 65 GPa a second structural transition to a Pmma space group was shown to take place [5], similar to that in Fe3-xTixO4 solid solution [6]. Other studies have focused on the P-T stability of Fe3O4. Early studies by Lazor et al. [7] predicted that Fe3O4 might disproportionate into FeO and h-Fe2O3 at 50 GPa. Other studies suggested that the high-pressure phase should be stable up to 100 GPa [3]. A more recent experimental study by Ricolleau and Fei [8] revealed that Fe3O4 is stable at least up to 103 GPa. Thus far, structural studies of Fe3O4 have been limited to pressures below 105 GPa. We have studied Fe3O4 up to pressures of 175 GPa and temperatures above 4000K, using diamond anvil cells in combination with synchrotron x-ray diffraction and an online pulsed laser-heating system to study the stability of Fe3O4 at relevant pressure-temperature conditions. Our results show that Fe3O4 is stable up to at least 176 GPa and 4200 K. We have discovered a new polymorph of Fe3O4 at these high P-T conditions. This new phase is stable in the pressure range of at least 100Journal of Physics: Condensed Matter 15, 7697 (2003). [4] Xu et al. Pysical Review B 70, 174106 (2004). [5] Greenberg et al. Physical Review B 95, 195150 (2017). [6] Yamanaka et al. American Mineralogist 98, 736 (2013). [7] Lazor et al. Journal of Geophysical Research 109, B05201 (2004). [8] Ricolleau and Fei. American Mineralogist 101, 719 (2016).

  10. The meteorology and chemistry of high nitrogen oxide concentrations in the stable boundary layer at the South Pole

    Science.gov (United States)

    Neff, William; Crawford, Jim; Buhr, Marty; Nicovich, John; Chen, Gao; Davis, Douglas

    2018-03-01

    Four summer seasons of nitrogen oxide (NO) concentrations were obtained at the South Pole (SP) during the Sulfur Chemistry in the Antarctic Troposphere (ISCAT) program (1998 and 2000) and the Antarctic Tropospheric Chemistry Investigation (ANTCI) in (2003, 2005, 2006-2007). Together, analyses of the data collected from these studies provide insight into the large- to small-scale meteorology that sets the stage for extremes in NO and the significant variability that occurs day to day, within seasons, and year to year. In addition, these observations reveal the interplay between physical and chemical processes at work in the stable boundary layer of the high Antarctic plateau. We found a systematic evolution of the large-scale wind system over the ice sheet from winter to summer that controls the surface boundary layer and its effect on NO: initially in early spring (Days 280-310) the transport of warm air and clouds over West Antarctica dominates the environment over the SP; in late spring (Days 310-340), the winds at 300 hPa exhibit a bimodal behavior alternating between northwest and southeast quadrants, which is of significance to NO; in early summer (Days 340-375), the flow aloft is dominated by winds from the Weddell Sea; and finally, during late spring, winds aloft from the southeast are strongly associated with clear skies, shallow stable boundary layers, and light surface winds from the east - it is under these conditions that the highest NO occurs. Examination of the winds at 300 hPa from 1961 to 2013 shows that this seasonal pattern has not changed significantly, although the last twenty years have seen an increasing trend in easterly surface winds at the SP. What has also changed is the persistence of the ozone hole, often into early summer. With lower total ozone column density and higher sun elevation, the highest actinic flux responsible for the photolysis of snow nitrate now occurs in late spring under the shallow boundary layer conditions optimum for

  11. Toward Isolation of Salient Features in Stable Boundary Layer Wind Fields that Influence Loads on Wind Turbines

    Directory of Open Access Journals (Sweden)

    Jinkyoo Park

    2015-04-01

    Full Text Available Neutral boundary layer (NBL flow fields, commonly used in turbine load studies and design, are generated using spectral procedures in stochastic simulation. For large utility-scale turbines, stable boundary layer (SBL flow fields are of great interest because they are often accompanied by enhanced wind shear, wind veer, and even low-level jets (LLJs. The generation of SBL flow fields, in contrast to simpler stochastic simulation for NBL, requires computational fluid dynamics (CFD procedures to capture the physics and noted characteristics—such as shear and veer—that are distinct from those seen in NBL flows. At present, large-eddy simulation (LES is the most efficient CFD procedure for SBL flow field generation and related wind turbine loads studies. Design standards, such as from the International Electrotechnical Commission (IEC, provide guidance albeit with simplifying assumptions (one such deals with assuming constant variance of turbulence over the rotor and recommend standard target turbulence power spectra and coherence functions to allow NBL flow field simulation. In contrast, a systematic SBL flow field simulation procedure has not been offered for design or for site assessment. It is instructive to compare LES-generated SBL flow fields with stochastic NBL flow fields and associated loads which we evaluate for a 5-MW turbine; in doing so, we seek to isolate distinguishing characteristics of wind shear, wind veer, and turbulence variation over the rotor plane in the alternative flow fields and in the turbine loads. Because of known differences in NBL-stochastic and SBL-LES wind fields but an industry preference for simpler stochastic simulation in design practice, this study investigates if one can reproduce stable atmospheric conditions using stochastic approaches with appropriate corrections for shear, veer, turbulence, etc. We find that such simple tuning cannot consistently match turbine target SBL load statistics, even though

  12. A stable-isotope tree-ring timescale of the Late Glacial/Holocene boundary

    International Nuclear Information System (INIS)

    Becker, Bernd; Kromer, Bernd; Trimborn, Peter

    1991-01-01

    Late Glacial and Holocene tree-ring chronologies, like deep-sea sediments or polar ice cores, contain information about past environments. Changes in tree-ring growth rates can be related to past climate anomalies and changes in the isotope composition of tree-ring cellulose reflect changes in the composition of the atmosphere and the hydrosphere. We have established a 9,928-year absolutely dated dendrochronological record of Holocene oak (Quercus robur, Quercus petraea)-and a 1,604-year floating Late Glacial and Early Holocene chronology of pine (Pinus sylvestris) from subfossil tree remnants deposited in alluvial terraces of south central European rivers. The pine sequence provides records of dendro-dated 14 C, 13 C and 2 H patterns for the late Younger Dryas and the entire Preboreal (10,100-9,000 yr BP). Through the use of dendrochronology, radiocarbon age calibration and stable isotope analysis, we suggest that the Late Glacial/Holocene transition may be identified and dated by 13 C and 2 H tree-ring chronologies. (author)

  13. Atomic-scale structure and properties of highly stable antiphase boundary defects in Fe3O4.

    Science.gov (United States)

    McKenna, Keith P; Hofer, Florian; Gilks, Daniel; Lazarov, Vlado K; Chen, Chunlin; Wang, Zhongchang; Ikuhara, Yuichi

    2014-12-10

    The complex and intriguing properties of the ferrimagnetic half metal magnetite (Fe 3 O 4 ) are of continuing fundamental interest as well as being important for practical applications in spintronics, magnetism, catalysis and medicine. There is considerable speculation concerning the role of the ubiquitous antiphase boundary (APB) defects in magnetite, however, direct information on their structure and properties has remained challenging to obtain. Here we combine predictive first principles modelling with high-resolution transmission electron microscopy to unambiguously determine the three-dimensional structure of APBs in magnetite. We demonstrate that APB defects on the {110} planes are unusually stable and induce antiferromagnetic coupling between adjacent domains providing an explanation for the magnetoresistance and reduced spin polarization often observed. We also demonstrate how the high stability of the {110} APB defects is connected to the existence of a metastable bulk phase of Fe 3 O 4 , which could be stabilized by strain in films or nanostructures.

  14. Three dimensional boundary displacement due to stable ideal kink modes excited by external n = 2 magnetic perturbations

    Science.gov (United States)

    Willensdorfer, M.; Strumberger, E.; Suttrop, W.; Dunne, M.; Fischer, R.; Birkenmeier, G.; Brida, D.; Cavedon, M.; Denk, S. S.; Igochine, V.; Giannone, L.; Kirk, A.; Kirschner, J.; Medvedeva, A.; Odstrčil, T.; Ryan, D. A.; The ASDEX Upgrade Team; The EUROfusion MST1 Team

    2017-11-01

    In low-collisionality (ν\\star) scenarios exhibiting mitigation of edge localized mode (ELMs), stable ideal kink modes at the edge are excited by externally applied magnetic perturbation (MP)-fields. In ASDEX Upgrade these modes can cause three-dimensional (3D) boundary displacements up to the centimeter range. These displacements have been measured using toroidally localized high resolution diagnostics and rigidly rotating n=2 MP-fields with various applied poloidal mode spectra. These measurements are compared to non-linear 3D ideal magnetohydrodynamics (MHD) equilibria calculated by VMEC. Comprehensive comparisons have been conducted, which consider for instance plasma movements due to the position control system, attenuation due to internal conductors and changes in the edge pressure profiles. VMEC accurately reproduces the amplitude of the displacement and its dependencies on the applied poloidal mode spectra. Quantitative agreement is found around the low field side (LFS) midplane. The response at the plasma top is qualitatively compared. The measured and predicted displacements at the plasma top maximize when the applied spectra is optimized for ELM-mitigation. The predictions from the vacuum modeling generally fails to describe the displacement at the LFS midplane as well as at the plasma top. When the applied mode spectra is set to maximize the displacement, VMEC and the measurements clearly surpass the predictions from the vacuum modeling by a factor of four. Minor disagreements between VMEC and the measurements are discussed. This study underlines the importance of the stable ideal kink modes at the edge for the 3D boundary displacement in scenarios relevant for ELM-mitigation.

  15. A Metal Stable Isotope Approach to Understanding Uranium Mobility Across Roll Front Redox Boundaries

    Science.gov (United States)

    Brown, S. T.; Basu, A.; Christensen, J. N.; DePaolo, D. J.; Heikoop, J. M.; Reimus, P. W.; Maher, K.; Weaver, K. L.

    2015-12-01

    Sedimentary roll-front uranium (U) ore deposits are the principal source of U for nuclear fuel in the USA and an important part of the current all-of-the-above energy strategy. Mining of roll-front U ore in the USA is primarily by in situ alkaline oxidative dissolution of U minerals. There are significant environmental benefits to in situ mining including no mine tailings or radioactive dust, however, the long-term immobilization of U in the aquifer after the completion of mining remains uncertain. We have utilized the metal stable isotopes U, Se and Mo in groundwater from roll-front mines in Texas and Wyoming to quantify the aquifer redox conditions and predict the onset of U reduction after post mining aquifer restoration. Supporting information from the geochemistry of groundwater and aquifer sediments are used to understand the transport of U prior to and after in situ mining. Groundwater was collected across 4 mining units at the Rosita mine in the Texas coastal plain and 2 mining units at the Smith Ranch mine in the Powder River Basin, Wyoming. In general, the sampled waters are moderately reducing and ore zone wells contain the highest aqueous U concentrations. The lowest U concentrations occur in monitoring wells downgradient of the ore zone. 238U/235U is lowest in downgradient wells and is correlated with aqueous U concentrations. Rayleigh distillation models of the 238U/235U are consistent with U isotope fractionation factors of 1.0004-1.001, similar to lab-based studies. Based on these results we conclude that redox reactions continue to affect U distribution in the ore zone and downgradient regions. We also measured aqueous selenium isotope (δ82Se) and molybdenum isotope (δ98Mo) compositions in the Rosita groundwater. Se(VI) primarily occurs in the upgradient wells and is absent in most ore zone and downgradient wells. Rayleigh distillation models suggest reduction of Se(VI) along the groundwater flow path and when superimposed on the U isotope data

  16. Adaptation of benthic invertebrates to food sources along marine-terrestrial boundaries as indicated by carbon and nitrogen stable isotopes

    Science.gov (United States)

    Lange, G.; Haynert, K.; Dinter, T.; Scheu, S.; Kröncke, I.

    2018-01-01

    Frequent environmental changes and abiotic gradients of the Wadden Sea require appropriate adaptations of the local organisms and make it suitable for investigations on functional structure of macrozoobenthic communities from marine to terrestrial boundaries. To investigate community patterns and food use of the macrozoobenthos, a transect of 11 stations was sampled for species number, abundance and stable isotope values (δ13C and δ15N) of macrozoobenthos and for stable isotope values of potential food resources. The transect was located in the back-barrier system of the island of Spiekeroog (southern North Sea, Germany). Our results show that surface and subsurface deposit feeders, such as Peringia ulvae and different oligochaete species, dominated the community, which was poor in species, while species present at the transect stations reached high abundance. The only exception was the upper salt marsh with low abundances but higher species richness because of the presence of specialized semi-terrestrial and terrestrial taxa. The macrozoobenthos relied predominantly on marine resources irrespective of the locality in the intertidal zone, although δ13C values of the consumers decreased from - 14.1 ± 1.6‰ (tidal flats) to - 21.5 ± 2.4‰ (salt marsh). However, the ubiquitous polychaete Hediste diversicolor showed a δ15N enrichment of 2.8‰ (an increase of about one trophic level) from bare sediments to the first vegetated transect station, presumably due to switching from suspension or deposit feeding to predation on smaller invertebrates. Hence, we conclude that changes in feeding mode represent an important mechanism of adaptation to different Wadden Sea habitats.

  17. Effects of Boundary Layer Height on the Model of Ground-Level PM2.5 Concentrations from AOD: Comparison of Stable and Convective Boundary Layer Heights from Different Methods

    Directory of Open Access Journals (Sweden)

    Zengliang Zang

    2017-06-01

    Full Text Available The aerosol optical depth (AOD from satellites or ground-based sun photometer spectral observations has been widely used to estimate ground-level PM2.5 concentrations by regression methods. The boundary layer height (BLH is a popular factor in the regression model of AOD and PM2.5, but its effect is often uncertain. This may result from the structures between the stable and convective BLHs and from the calculation methods of the BLH. In this study, the boundary layer is divided into two types of stable and convective boundary layer, and the BLH is calculated using different methods from radiosonde data and National Centers for Environmental Prediction (NCEP reanalysis data for the station in Beijing, China during 2014–2015. The BLH values from these methods show significant differences for both the stable and convective boundary layer. Then, these BLHs were introduced into the regression model of AOD-PM2.5 to seek the respective optimal BLH for the two types of boundary layer. It was found that the optimal BLH for the stable boundary layer is determined using the method of surface-based inversion, and the optimal BLH for the convective layer is determined using the method of elevated inversion. Finally, the optimal BLH and other meteorological parameters were combined to predict the PM2.5 concentrations using the stepwise regression method. The results indicate that for the stable boundary layer, the optimal stepwise regression model includes the factors of surface relative humidity, BLH, and surface temperature. These three factors can significantly enhance the prediction accuracy of ground-level PM2.5 concentrations, with an increase of determination coefficient from 0.50 to 0.68. For the convective boundary layer, however, the optimal stepwise regression model includes the factors of BLH and surface wind speed. These two factors improve the determination coefficient, with a relatively low increase from 0.65 to 0.70. It is found that the

  18. Current management of nocturnal enuresis.

    Science.gov (United States)

    Robson, Wm Lane M

    2008-07-01

    Nocturnal enuresis is an especially common problem with the potential to have an appreciable negative impact on the emotional health of a child. Our understanding of the pathogenesis continues to improve. A disorder of sleep arousal, a low nocturnal bladder capacity, and nocturnal polyuria are the three factors that interrelate to cause nocturnal enuresis. Constipation is a very common and often unrecognized factor that appreciably affects bladder function. Successful treatment involves interventions that simultaneously improve these factors. Self-esteem improves with any form of therapy and dryness is possible for the majority of children.

  19. A new first-order turbulence mixing model for the stable atmospheric boundary-layer: development and testing in large-eddy and single column models

    Science.gov (United States)

    Huang, J.; Bou-Zeid, E.; Golaz, J.

    2011-12-01

    Parameterization of the stably-stratified atmospheric boundary-layer is of crucial importance to different aspects of numerical weather prediction at regional scales and climate modeling at global scales, such as land-surface temperature forecasts, fog and frost prediction, and polar climate. It is well-known that most operational climate models require excessive turbulence mixing of the stable boundary-layer to prevent decoupling of the atmospheric component from the land component under strong stability, but the performance of such a model is unlikely to be satisfactory under weakly and moderately stable conditions. In this study we develop and test a general turbulence mixing model of the stable boundary-layer which works under different stabilities and for steady as well as unsteady conditions. A-priori large-eddy simulation (LES) tests are presented to motivate and verify the new parameterization. Subsequently, an assessment of this model using the GFDL single-column model (SCM) is performed. Idealized test cases including continuously varying stability, as well as stability discontinuity, are used to test the new SCM against LES results. A good match of mean and flux profiles is found when the new parameterization is used, while other traditional first-order turbulence models using the concept of stability function perform poorly. SCM spatial resolution is also found to have little impact on the performance of the new turbulence closure, but temporal resolution is important and a numerical stability criterion based on the model time step is presented.

  20. Impact of height-dependent drainage forcing on the stable atmospheric boundary layer over a uniform slope

    International Nuclear Information System (INIS)

    Maguire, A.J.; Rees, J.M.; Derbyshire, S.H.

    2008-01-01

    This paper presents a theoretical study of the stably stratified atmospheric boundary layer (SBL) overlying a uniform shallow slope with a gradient of the order of 1:1000. By relaxing the assumption made in a previous study that the slope-induced drainage force is constant across the boundary layer, analysis has been performed that demonstrates that a realistic form for the drainage forcing is a term proportional to (1-z/h) 1/2 , where z is the height above the ground and h is the depth of the boundary layer. Modified expressions for the maximum sustainable surface buoyancy flux and Zilitinkevich's ratio are derived.

  1. Pathophysiology of nocturnal enuresis

    DEFF Research Database (Denmark)

    Rittig, Søren; Kamperis, Konstantinos

    2015-01-01

    The perception of the pathogenesis of enuresis has undergone marked changes over the past 30 years from a psychiatric/psychological background to a more somatic model where nighttime urine production and bladder capacity are main components together with an arousal dysfunction that prevents...... that dysfunction of the intrinsic circadian regulation located in the suprachiasmatic nucleus results in dysfunction of one or more of the brainstem centers involved in AVP secretion, arousal function, bladder control, and blood pressure regulation. Furthermore, nocturnal enuresis has a strong genetic influence...... that in some families present as autosomal dominant inheritance with high degree of penetrance. Linkage to several chromosomal areas have been confirmed in such families although a specific causative enuresis gene has not yet been identified. In conclusion, our understanding of enuresis pathophysiology has...

  2. An energy-stable method for solving the incompressible Navier-Stokes equations with non-slip boundary condition

    Science.gov (United States)

    Lee, Byungjoon; Min, Chohong

    2018-05-01

    We introduce a stable method for solving the incompressible Navier-Stokes equations with variable density and viscosity. Our method is stable in the sense that it does not increase the total energy of dynamics that is the sum of kinetic energy and potential energy. Instead of velocity, a new state variable is taken so that the kinetic energy is formulated by the L2 norm of the new variable. Navier-Stokes equations are rephrased with respect to the new variable, and a stable time discretization for the rephrased equations is presented. Taking into consideration the incompressibility in the Marker-And-Cell (MAC) grid, we present a modified Lax-Friedrich method that is L2 stable. Utilizing the discrete integration-by-parts in MAC grid and the modified Lax-Friedrich method, the time discretization is fully discretized. An explicit CFL condition for the stability of the full discretization is given and mathematically proved.

  3. Nocturnal Low-level Jet Evolution in a Broad Valley Observed by Dual Doppler Lidar

    Directory of Open Access Journals (Sweden)

    Thomas Damian

    2014-09-01

    Full Text Available The temporal evolution of a nocturnal low-level jet (LLJ in the 40km$40\\,\\text{km}$ broad Rhine Valley near Karlsruhe is studied, in the framework of a case study, with two heterodyne detection Doppler lidars using the new scan concept of “virtual towers”. For validation of this measuring technique, we performed comparative case studies with a tethered balloon and the highly instrumented 200m$200\\,\\text{m}$ KIT tower. The findings show capabilities of the virtual tower technique for wind measurements. Virtual towers can be placed at all locations within the range of Lidar measurements. Associated with nocturnal stable stratification, the LLJ, a wind speed maximum of about 9ms-1$9\\,\\text{m}\\,\\text{s}^{-1}$, develops at 100m$100\\,\\text{m}$ to 150m$150\\,\\text{m}$ agl, but the wind does not show the typical clockwise wind direction change that is reported in many other studies. This is attributed to the channeling effect occurring in broad valleys like the Rhine Valley when the boundary layer is stably stratified. Such channeling means a significant deviation of the wind direction from the Ekman spiral so that low-altitude winds turn into valley-parallel direction.

  4. Stable carbon isotope analysis of soil organic matter illustrates vegetation change at the grassland/woodland boundary in southeastern Arizona, USA.

    Science.gov (United States)

    McPherson, G R; Boutton, T W; Midwood, A J

    1993-02-01

    In southeastern Arizona, Prosopis juliflora (Swartz) DC. and Quercus emoryi Torr. are the dominant woody species at grassland/woodland boundaries. The stability of the grassland/woodland boundary in this region has been questioned, although there is no direct evidence to confirm that woodland is encroaching into grassland or vice versa. We used stable carbon isotope analysis of soil organic matter to investigate the direction and magnitude of vegetation change along this ecotone. δ 13 C values of soil organic matter and roots along the ecotone indicated that both dominant woody species (C 3 ) are recent components of former grasslands (C 4 ), consistent with other reports of recent increases in woody plant abundance in grasslands and savannas throughout the world. Data on root biomass and soil organic matter suggest that this increase in woody plant abundance in grasslands and savannas may increase carbon storage in these ecosystems, with implications for the global carbon cycle.

  5. Monosymptomatic nocturnal enuresis

    Directory of Open Access Journals (Sweden)

    Bertan Karaboğa

    2012-03-01

    Full Text Available Enuresis Nocturna is the most common urologic problemin childhood. There is not a consensus about terminology.Terminology identified by The International Children’sContinence Society (ICCS is recommended. Bed-wettingat night during sleep (incontinence in children above 5years of age who don’t have congenital or acquired centralnervous system defect is defined as enuresis nocturna.There are two groups monosymptomatic (simpleand non-monosymptomatic (complicated. Monosymptomaticenuresis nocturna (MNE has no symptoms otherthan bed-wetting at night during sleep. Various theoriesconcerning etiology of MNE has been suggested; one ormore of genetic, hormonal, bladder associated and sleepdisorders are stated to play a role. Self-improvement canbe achieved each year by 15% increasing maturity. Underpinning treatment and in addition to this unique treatmentmust be done by considering the factors in the pathophysiology.The success of the treatment and roadmapto be followed must be arrange with child and family. Thepurpose of this eclectic is; evaluation of correct diagnosis,differential diagnosis, patient follow-up and treatment optionsof the cases applicant with nocturnal enuresis basedon the current knowledge of ICCS and Turkey EnuresisTreatment Guide.

  6. Defining a stable water isotope framework for isotope hydrology application in a large trans-boundary watershed (Russian Federation/Ukraine).

    Science.gov (United States)

    Vystavna, Yuliya; Diadin, Dmytro; Huneau, Frédéric

    2018-05-01

    Stable isotopes of hydrogen ( 2 H) and oxygen ( 18 O) of the water molecule were used to assess the relationship between precipitation, surface water and groundwater in a large Russia/Ukraine trans-boundary river basin. Precipitation was sampled from November 2013 to February 2015, and surface water and groundwater were sampled during high and low flow in 2014. A local meteoric water line was defined for the Ukrainian part of the basin. The isotopic seasonality in precipitation was evident with depletion in heavy isotopes in November-March and an enrichment in April-October, indicating continental and temperature effects. Surface water was enriched in stable water isotopes from upstream to downstream sites due to progressive evaporation. Stable water isotopes in groundwater indicated that recharge occurs mainly during winter and spring. A one-year data set is probably not sufficient to report the seasonality of groundwater recharge, but this survey can be used to identify the stable water isotopes framework in a weakly gauged basin for further hydrological and geochemical studies.

  7. Ocellar optics in nocturnal and diurnal bees and wasps.

    Science.gov (United States)

    Warrant, Eric J; Kelber, Almut; Wallén, Rita; Wcislo, William T

    2006-12-01

    Nocturnal bees, wasps and ants have considerably larger ocelli than their diurnal relatives, suggesting an active role in vision at night. In a first step to understanding what this role might be, the morphology and physiological optics of ocelli were investigated in three tropical rainforest species - the nocturnal sweat bee Megalopta genalis, the nocturnal paper wasp Apoica pallens and the diurnal paper wasp Polistes occidentalis - using hanging-drop techniques and standard histological methods. Ocellar image quality, in addition to lens focal length and back focal distance, was determined in all three species. During flight, the ocellar receptive fields of both nocturnal species are centred very dorsally, possibly in order to maximise sensitivity to the narrow dorsal field of light that enters through gaps in the rainforest canopy. Since all ocelli investigated had a slightly oval shape, images were found to be astigmatic: images formed by the major axis of the ocellus were located further from the proximal surface of the lens than images formed by the minor axis. Despite being astigmatic, images formed at either focal plane were reasonably sharp in all ocelli investigated. When compared to the position of the retina below the lens, measurements of back focal distance reveal that the ocelli of Megalopta are highly underfocused and unable to resolve spatial detail. This together with their very large and tightly packed rhabdoms suggests a role in making sensitive measurements of ambient light intensity. In contrast, the ocelli of the two wasps form images near the proximal boundary of the retina, suggesting the potential for modest resolving power. In light of these results, possible roles for ocelli in nocturnal bees and wasps are discussed, including the hypothesis that they might be involved in nocturnal homing and navigation, using two main cues: the spatial pattern of bright patches of daylight visible through the rainforest canopy, and compass information

  8. Covalently Connecting Crystal Grains with Polyvinylammonium Carbochain Backbone To Suppress Grain Boundaries for Long-Term Stable Perovskite Solar Cells.

    Science.gov (United States)

    Li, Han; Liang, Chao; Liu, Yingliang; Zhang, Yiqiang; Tong, Jincheng; Zuo, Weiwei; Xu, Shengang; Shao, Guosheng; Cao, Shaokui

    2017-02-22

    Grain boundaries act as rapid pathways for nonradiative carrier recombination, anion migration, and water corrosion, leading to low efficiency and poor stability of organometal halide perovskite solar cells (PSCs). In this work, the strategy suppressing the crystal grain boundaries is applied to improve the photovoltaic performance, especially moisture-resistant stability, with polyvinylammonium carbochain backbone covalently connecting the perovskite crystal grains. This cationic polyelectrolyte additive serves as nucleation sites and template for crystal growth of MAPbI 3 and afterward the immobilized adjacent crystal grains grow into the continuous compact, pinhole-free perovskite layer. As a result, the unsealed PSC devices, which are fabricated under low-temperature fabrication protocol with a proper content of polymer additive PVAm·HI, currently exhibit the maximum efficiency of 16.3%. Remarkably, these unsealed devices follow an "outside-in" corrosion mechanism and respectively retain 92% and 80% of the initial PCE value after being exposed under ambient environment for 50 days and 100 days, indicating the superiority of carbochain polymer additives in solving the long-term stability problem of PSCs.

  9. Combined effect of boundary layer recirculation factor and stable energy on local air quality in the Pearl River Delta over southern China.

    Science.gov (United States)

    Li, Haowen; Wang, Baomin; Fang, Xingqin; Zhu, Wei; Fan, Qi; Liao, Zhiheng; Liu, Jian; Zhang, Asi; Fan, Shaojia

    2018-03-01

    Atmospheric boundary layer (ABL) has a significant impact on the spatial and temporal distribution of air pollutants. In order to gain a better understanding of how ABL affects the variation of air pollutants, atmospheric boundary layer observations were performed at Sanshui in the Pearl River Delta (PRD) region over southern China during the winter of 2013. Two types of typical ABL status that could lead to air pollution were analyzed comparatively: weak vertical diffusion ability type (WVDAT) and weak horizontal transportation ability type (WHTAT). Results show that (1) WVDAT was featured by moderate wind speed, consistent wind direction, and thick inversion layer at 600~1000 m above ground level (AGL), and air pollutants were restricted in the low altitudes due to the stable atmospheric structure; (2) WHTAT was characterized by calm wind, varied wind direction, and shallow intense ground inversion layer, and air pollutants accumulated in locally because of strong recirculation in the low ABL; (3) recirculation factor (RF) and stable energy (SE) were proved to be good indicators for horizontal transportation ability and vertical diffusion ability of the atmosphere, respectively. Combined utilization of RF and SE can be very helpful in the evaluation of air pollution potential of the ABL. Air quality data from ground and meteorological data collected from radio sounding in Sanshui in the Pearl River Delta showed that local air quality was poor when wind reversal was pronounced or temperature stratification state was stable. The combination of horizontal and vertical transportation ability of the local atmosphere should be taken into consideration when evaluating local environmental bearing capacity for air pollution.

  10. Cs/CsPbX3 (X = Br, Cl) epitaxial heteronanocrystals with magic-angle stable/metastable grain boundary

    Science.gov (United States)

    Zhang, Yumeng; Fan, Baolu; Wu, Wenhui; Fan, Jiyang

    2017-05-01

    Metal-semiconductor heteronanostructures are crucial building blocks of nanoscale electronic and optoelectronic devices. However, the lattice misfit remains a challenge in constructing heteronanostructures. Perovskite nanocrystals are superior candidates for constructing nanodevices owing to excellent optical, ferroelectric, and superconducting properties. We report the epitaxial growth of lattice-matched Cs/CsPbBr3 metal-semiconductor heteronanocrystals in a liquid medium. The well-crystallized ultrathin Cs layers grow epitaxially on the surfaces of colloidal CsPbBr3 nanocrystals, forming heteronanocrystals with interface diameters of several nanometers. Most of them are pseudomorphic with coherent interfaces free from dislocations, and the others exhibit discrete high-angle grain boundaries. The model based on the calculation of the elastic potential energy of the epilayer and analysis of the near-coincidence sites explains well the experimental result. The analysis shows that the excellent lattice match between the metal and the semiconductor ensures the ideal epitaxial-growth of both Cs/CsPbBr3 and Cs/CsPbCl3 heteronanocrystals. Such metal/semiconductor heteronanocrystals pave the way for developing perovskite-based nanodevices.

  11. Pregnancy and paroxysmal nocturnal hemoglobinuria

    NARCIS (Netherlands)

    Bais, J.; Pel, M.; von dem Borne, A.; van der Lelie, H.

    1994-01-01

    A patient is described who developed symptoms of paroxysmal nocturnal hemoglobinuria (PNH) in her first pregnancy. This was uneventful except for a spontaneous preterm delivery. The second pregnancy was complicated by severe anemia and a hemolytic crisis with Budd-Chiari syndrome at 31 weeks'

  12. Unconditionally stable methods for simulating multi-component two-phase interface models with Peng-Robinson equation of state and various boundary conditions

    KAUST Repository

    Kou, Jisheng

    2015-03-01

    In this paper, we consider multi-component dynamic two-phase interface models, which are formulated by the Cahn-Hilliard system with Peng-Robinson equation of state and various boundary conditions. These models can be derived from the minimum problems of Helmholtz free energy or grand potential in the realistic thermodynamic systems. The resulted Cahn-Hilliard systems with various boundary conditions are fully coupled and strongly nonlinear. A linear transformation is introduced to decouple the relations between different components, and as a result, the models are simplified. From this, we further propose a semi-implicit unconditionally stable time discretization scheme, which allows us to solve the Cahn-Hilliard system by a decoupled way, and thus, our method can significantly reduce the computational cost and memory requirements. The mixed finite element methods are employed for the spatial discretization, and the approximate errors are also analyzed for both space and time. Numerical examples are tested to demonstrate the efficiency of our proposed methods. © 2015 Elsevier B.V.

  13. [Nocturnal polyuria, treatment with desmopressin].

    Science.gov (United States)

    Zachoval, R; Krhut, J; Šottner, O; Hanuš, T; Martan, A; Horčička, L; Feyereisl, J; Halaška, M; Švabík, K; Krofta, L

    2013-08-01

    Nonpharmacologic and especially pharmacologic treatment options are available for nocturnal polyuria. Desmopressin represents the basis of pharmacologic treatment. Desmopressin acetate is a synthetic analogue of arginine vasopressin with high affinity to V2 receptors with antidiuretic effect. It is the only medicament currently registered for antidiuretic treatment. Desmopressin has not any relevant affinity to V1 receptors, and therefore there is no hypertensive effect in contrary to natural vasopressin. Desmopressin use before a bedtime leads to reduced production of urine during a sleep, therefore time between desires to void is prolonged and number of nocturia is reduced. Clinical effect, in a meaning of reduced urine production and increased osmolality of urine, lasts approximately 8-12 hours. In the treatment of nocturnal polyuria desmopressin is used orally one hour before a bedtime. It is essential to titrate an ideal dose, the initial dose is 60 µg of MELT formula (fast melting oral formulation) and it can be increased according to the clinical effect up to the maximal recommended daily dose 240 µg. Patients treated with desmopressin should cut down a fluid intake 1 hour before and 8 hours after the use of desmopressin. Total number of adverse events connected withdesmopressin treatment in clinical studies was higher compared to placebo but the side effects were mostly mild. The most common adverse events were headaches, nausea, diarrhoea, abdominal pain, dry mouth and hyponatremia both in the short-term and long-term clinical trials. Hyponatremia was observed mainly in patients over 65 year of age. Therefore treatment with desmopressin should not be commended in patients over 65 year of age without close monitoring of the natrium level in serum and all patients should be informed about the first symptoms of hyponatremia - headache, nausea and insomnia. According to Evidence Based Medicine, the level of evidence for treatment of nocturnal polyuria with

  14. Mercury fluxes over an Australian alpine grassland and observation of nocturnal atmospheric mercury depletion events

    Directory of Open Access Journals (Sweden)

    D. Howard

    2018-01-01

    Full Text Available Aerodynamic gradient measurements of the air–surface exchange of gaseous elemental mercury (GEM were undertaken over a 40 ha alpine grassland in Australia's Snowy Mountains region across a 3-week period during the late austral summer. Bi-directional GEM fluxes were observed throughout the study, with overall mean value of 0.2 ± 14.5 ng m−2 h−1 and mean nocturnal fluxes of −1.5 ± 7.8 ng m−2 h−1 compared to diurnal fluxes of 1.8 ± 18.6 ng m−2 h−1. Deposition velocities ranged from −2.2 to 2.9 cm s−1, whilst ambient GEM concentrations throughout the study were 0.59 ± 0.10 ng m−3. Cumulative GEM fluxes correlated well with 24 h running mean soil temperatures, and one precipitation event was shown to have a positive impact on diurnal emission fluxes. The underlying vegetation had largely senesced and showed little stomatal control on fluxes. Nocturnal atmospheric mercury depletion events (NAMDEs were observed concomitant with O3 depletion and dew formation under shallow, stable nocturnal boundary layers. A mass balance box model was able to reproduce ambient GEM concentration patterns during NAMDE and non-NAMDE nights without invoking chemical oxidation of GEM throughout the column, indicating a significant role of surface processes controlling deposition in these events. Surface deposition was enhanced under NAMDE nights, though uptake to dew likely represents less than one-fifth of this enhanced deposition. Instead, enhancement of the surface GEM gradient as a result of oxidation at the surface in the presence of dew is hypothesised to be responsible for a large portion of GEM depletion during these particular events. GEM emission pulses following nights with significant deposition provide evidence for the prompt recycling of 17 % of deposited mercury, with the remaining portion retained in surface sinks. The long-term impacts of any sinks are however likely to be minimal, as

  15. Tracking atmospheric boundary layer dynamics with water vapor D-excess observations

    KAUST Repository

    Parkes, Stephen

    2015-04-01

    Stable isotope water vapor observations present a history of hydrological processes that have impacted on an air mass. Consequently, there is scope to improve our knowledge of how different processes impact on humidity budgets by determining the isotopic end members of these processes and combining them with in-situ water vapor measurements. These in-situ datasets are still rare and cover a limited geographical expanse, so expanding the available data can improve our ability to define isotopic end members and knowledge about atmospheric humidity dynamics. Using data collected from an intensive field campaign across a semi-arid grassland site in eastern Australia, we combine multiple methods including in-situ stable isotope observations to study humidity dynamics associated with the growth and decay of the atmospheric boundary layer and the stable nocturnal boundary layer. The deuterium-excess (D-excess) in water vapor is traditionally thought to reflect the sea surface temperature and relative humidity at the point of evaporation over the oceans. However, a number of recent studies suggest that land-atmosphere interactions are also important in setting the D-excess of water vapor. These studies have shown a highly robust diurnal cycle for the D-excess over a range of sites that could be exploited to better understand variations in atmospheric humidity associated with boundary layer dynamics. In this study we use surface radon concentrations as a tracer of surface layer dynamics and combine these with the D-excess observations. The radon concentrations showed an overall trend that was inversely proportional to the D-excess, with early morning entrainment of air from the residual layer of the previous day both diluting the radon concentration and increasing the D-excess, followed by accumulation of radon at the surface and a decrease in the D-excess as the stable nocturnal layer developed in the late afternoon and early evening. The stable nocturnal boundary layer

  16. Running Club - Nocturne des Evaux

    CERN Multimedia

    Running club

    2017-01-01

    Les coureurs du CERN sont encore montés sur les plus hautes marches du podium lors de la course interentreprises. Cette course d’équipe qui se déroule de nuit et par équipe de 3 à 4 coureurs est unique dans la région de par son originalité : départ groupé toutes les 30 secondes, les 3 premiers coureurs doivent passer la ligne d’arrivée ensemble. Double victoire pour le running club a la nocturne !!!! 1ère place pour les filles et 22e au classement général; 1ère place pour l'équipe mixte et 4e au général, battant par la même occasion le record de l'épreuve en mixte d'environ 1 minute; 10e place pour l'équipe homme. Retrouvez tous les résultats sur http://www.chp-geneve.ch/web-cms/index.php/nocturne-des-evaux

  17. Niche convergence suggests functionality of the nocturnal fovea.

    Science.gov (United States)

    Moritz, Gillian L; Melin, Amanda D; Tuh Yit Yu, Fred; Bernard, Henry; Ong, Perry S; Dominy, Nathaniel J

    2014-01-01

    The fovea is a declivity of the retinal surface associated with maximum visual acuity. Foveae are widespread across vertebrates, but among mammals they are restricted to haplorhine primates (tarsiers, monkeys, apes, and humans), which are primarily diurnal. Thus primates have long contributed to the view that foveae are functional adaptations to diurnality. The foveae of tarsiers, which are nocturnal, are widely interpreted as vestigial traits and therefore evidence of a diurnal ancestry. This enduring premise is central to adaptive hypotheses on the origins of anthropoid primates; however, the question of whether tarsier foveae are functionless anachronisms or nocturnal adaptations remains open. To explore this question, we compared the diets of tarsiers (Tarsius) and scops owls (Otus), taxa united by numerous anatomical homoplasies, including foveate vision. A functional interpretation of these homoplasies predicts dietary convergence. We tested this prediction by analyzing stable isotope ratios that integrate dietary information. In Borneo and the Philippines, the stable carbon isotope compositions of Tarsius and Otus were indistinguishable, whereas the stable nitrogen isotope composition of Otus was marginally higher than that of Tarsius. Our results indicate that species in both genera consumed mainly ground-dwelling prey. Taken together, our findings support a functional interpretation of the many homoplasies shared by tarsiers and scops owls, including a retinal fovea. We suggest that the fovea might function similarly in tarsiers and scops owls by calibrating the auditory localization pathway. The integration of auditory localization and visual fixation during prey detection and acquisition might be critical at low light levels.

  18. Treatment of paroxysmal nocturnal hemoglobinuria

    Directory of Open Access Journals (Sweden)

    I. A. Lisukov

    2014-07-01

    Full Text Available Paroxysmal nocturnal hemoglobinuria (PNH is a rare, life‑threatening clonal hematological disorder caused by an acquired mutation in the phosphatidylinositol glucan (PIG-A gene. PNH is characterized by chronic intravascular hemolysis, marrow failure, thrombophilia and other severe clinical syndromes. Until recently, the treatment of PNH has been symptomatic with blood transfusions, anticoagulation and supplementation with folic acid or iron. The only potentially curative treatment is allogeneic stem cell transplantation, but this has severe complications with high mortality rates. A new targeted treatment strategy is the inhibition of the terminal complement cascade with anti‑C5 monoclonal antibody (eculizumab. Eculizumab has shown significant efficacy in controlling of intravascular hemolysis resulting in improving quality of life and survival.

  19. Treatment of paroxysmal nocturnal hemoglobinuria

    Directory of Open Access Journals (Sweden)

    I. A. Lisukov

    2012-01-01

    Full Text Available Paroxysmal nocturnal hemoglobinuria (PNH is a rare, life‑threatening clonal hematological disorder caused by an acquired mutation in the phosphatidylinositol glucan (PIG-A gene. PNH is characterized by chronic intravascular hemolysis, marrow failure, thrombophilia and other severe clinical syndromes. Until recently, the treatment of PNH has been symptomatic with blood transfusions, anticoagulation and supplementation with folic acid or iron. The only potentially curative treatment is allogeneic stem cell transplantation, but this has severe complications with high mortality rates. A new targeted treatment strategy is the inhibition of the terminal complement cascade with anti‑C5 monoclonal antibody (eculizumab. Eculizumab has shown significant efficacy in controlling of intravascular hemolysis resulting in improving quality of life and survival.

  20. Exploring the role of wave drag in the stable stratified oceanic and atmospheric bottom boundary layer in the cnrs-toulouse (cnrm-game) large stratified water flume

    NARCIS (Netherlands)

    Kleczek, M.; Steeneveld, G.J.; Paci, A.; Calmer, R.; Belleudy, A.; Canonici, J.C.; Murguet, F.; Valette, V.

    2014-01-01

    This paper reports on a laboratory experiment in the CNRM-GAME (Toulouse) stratified water flume of a stably stratified boundary layer, in order to quantify the momentum transfer due to orographically induced gravity waves by gently undulating hills in a boundary layer flow. In a stratified fluid, a

  1. Effect of Nocturnal Haemodialysis on Body Composition

    NARCIS (Netherlands)

    Ipema, K.J.R.; Westerhuis, R.; van der Schans, C.P.; de Jong, P.E.; Gaillard, C.A. J. M.; Krijnen, W.P.; Slart, R.H.J.A.; Franssen, C.F.M.

    2014-01-01

    Background: Haemodialysis patients have a high risk of malnutrition which is associated with increased mortality. Nocturnal haemodialysis (NHD) is associated with a significant increase in protein intake compared with conventional haemodialysis (CHD). It is unclear whether this leads to improved

  2. Nocturnal Polyuria : Excess of Nocturnal Urine Production, Excess of Definitions-Influence on Renal Function Profile

    NARCIS (Netherlands)

    Goessaert, An-Sofie; Walle, Johan Vande; Bosch, JLHR; Hoebeke, Piet; Everaert, Karel

    2016-01-01

    PURPOSE: This study aimed to identify important differences in renal function profile, and potential water and sodium diuresis cutoffs among participants with nocturnal polyuria according to nocturnal polyuria definitions. MATERIALS AND METHODS: This post hoc analysis was based on a prospective

  3. Boundary layer height estimation by sodar and sonic anemometer measurements

    International Nuclear Information System (INIS)

    Contini, D; Cava, D; Martano, P; Donateo, A; Grasso, F M

    2008-01-01

    In this paper an analysis of different methods for the calculation of the boundary layer height (BLH) using sodar and ultrasonic anemometer measurements is presented. All the methods used are based on single point surface measurements. In particular the automatic spectral routine developed for Remtech sodar is compared with the results obtained with the parameterization of the vertical velocity variance, with the calculation of a prognostic model and with a parameterization based on horizontal velocity spectra. Results indicate that in unstable conditions the different methods provide similar pattern, with BLH relatively low, even if the parameterization of the vertical velocity variance is affected by a large scatter that limits its efficiency in evaluating the BLH. In stable nocturnal conditions the performances of the Remtech routine are lower with respect to the ones in unstable conditions. The spectral method, applied to sodar or sonic anemometer data, seems to be the most promising in order to develop an efficient routine for BLH determination

  4. Effect of indomethacin on desmopressin resistant nocturnal polyuria and nocturnal enuresis.

    Science.gov (United States)

    Kamperis, Konstantinos; Rittig, Søren; Bower, Wendy F; Djurhuus, Jens C

    2012-11-01

    We evaluated the acute effect of indomethacin on renal water and solute handling in children with coexisting monosymptomatic nocturnal enuresis and desmopressin resistant nocturnal polyuria, and in healthy controls. A total of 23 subjects were recruited, consisting of 12 children with monosymptomatic nocturnal enuresis and nocturnal polyuria with partial or no response to desmopressin, and 11 age matched controls. Children completed a 48-hour inpatient study protocol consisting of fractional urine collections and blood samples. Sodium and water intake were standardized. During the second night a dose of 50 mg indomethacin was administered orally before bedtime. Diuresis, urine osmolalities, clearances and fractional excretions were calculated for sodium, potassium, urea, osmoles and solute-free water. Renin, angiotensin II, aldosterone and atrial natriuretic peptide were measured in plasma. Prostaglandin E(2) was measured in urine. Indomethacin markedly decreased the nocturnal sodium, urea and osmotic excretion in children with enuresis and controls. The overall effect on nocturnal urine output was inconsistent in the group with enuresis. Subjects in whom nocturnal diuresis was decreased following administration of indomethacin remained dry. Prostaglandin inhibition leads to antidiuresis, reducing the amount of sodium, urea and osmotic excretion in children with monosymptomatic nocturnal enuresis and desmopressin resistant nocturnal polyuria. The sodium regulating hormones do not seem to mediate these processes. The overall effect in desmopressin nonresponders with nocturnal polyuria is variable. The extent to which indomethacin can be applied in the treatment of enuresis needs further evaluation. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  5. Impact of the Diurnal Cycle of the Atmospheric Boundary Layer on Wind-Turbine Wakes: A Numerical Modelling Study

    Science.gov (United States)

    Englberger, Antonia; Dörnbrack, Andreas

    2018-03-01

    The wake characteristics of a wind turbine for different regimes occurring throughout the diurnal cycle are investigated systematically by means of large-eddy simulation. Idealized diurnal cycle simulations of the atmospheric boundary layer are performed with the geophysical flow solver EULAG over both homogeneous and heterogeneous terrain. Under homogeneous conditions, the diurnal cycle significantly affects the low-level wind shear and atmospheric turbulence. A strong vertical wind shear and veering with height occur in the nocturnal stable boundary layer and in the morning boundary layer, whereas atmospheric turbulence is much larger in the convective boundary layer and in the evening boundary layer. The increased shear under heterogeneous conditions changes these wind characteristics, counteracting the formation of the night-time Ekman spiral. The convective, stable, evening, and morning regimes of the atmospheric boundary layer over a homogeneous surface as well as the convective and stable regimes over a heterogeneous surface are used to study the flow in a wind-turbine wake. Synchronized turbulent inflow data from the idealized atmospheric boundary-layer simulations with periodic horizontal boundary conditions are applied to the wind-turbine simulations with open streamwise boundary conditions. The resulting wake is strongly influenced by the stability of the atmosphere. In both cases, the flow in the wake recovers more rapidly under convective conditions during the day than under stable conditions at night. The simulated wakes produced for the night-time situation completely differ between heterogeneous and homogeneous surface conditions. The wake characteristics of the transitional periods are influenced by the flow regime prior to the transition. Furthermore, there are different wake deflections over the height of the rotor, which reflect the incoming wind direction.

  6. Iatrogenic nocturnal eneuresis- an overlooked side effect of anti histamines?

    Directory of Open Access Journals (Sweden)

    D Italiano

    2015-01-01

    Full Text Available Nocturnal enuresis is a common disorder in childhood, but its pathophysiological mechanisms have not been fully elucidated. Iatrogenic nocturnal enuresis has been described following treatment with several psychotropic medications. Herein, we describe a 6-year-old child who experienced nocturnal enuresis during treatment with the antihistamine cetirizine. Drug rechallenge was positive. Several neurotransmitters are implicated in the pathogenesis of nocturnal enuresis, including noradrenaline, serotonin and dopamine. Antihistamine treatment may provoke functional imbalance of these pathways resulting in incontinence.

  7. Small-scale orographic gravity wave drag in stable boundary layers and its impact on synoptic systems and near surface meteorology

    NARCIS (Netherlands)

    Tsiringakis, Aristofanis; Steeneveld, G.J.; Holtslag, A.A.M.

    2017-01-01

    At present atmospheric models for weather and climate use enhanced turbulent drag under stable conditions, because these empirically provide the necessary momentum drag for accurate forecast of synoptic systems. The enhanced mixing (also known as the "long-tail"), introduces drag that can not be

  8. Monin-Obukhov Similarity Functions of the Structure Parameter of Temperature and Turbulent Kinetic Energy Dissipation Rate in the Stable Boundary Layer

    NARCIS (Netherlands)

    Hartogensis, O.K.; Debruin, H.A.R.

    2005-01-01

    The Monin-Obukhov similarity theory (MOST) functions fepsi; and fT, of the dissipation rate of turbulent kinetic energy (TKE), ¿, and the structure parameter of temperature, CT2, were determined for the stable atmospheric surface layer using data gathered in the context of CASES-99. These data cover

  9. Hexamethylenetetramine-mediated growth of grain-boundary-passivation CH3NH3PbI3 for highly reproducible and stable perovskite solar cells

    Science.gov (United States)

    Zheng, Yan-Zhen; Li, Xi-Tao; Zhao, Er-Fei; Lv, Xin-Ding; Meng, Fan-Li; Peng, Chao; Lai, Xue-Sen; Huang, Meilan; Cao, Guozhong; Tao, Xia; Chen, Jian-Feng

    2018-02-01

    Simultaneously achieving the long-term device stability and reproducibility has proven challenging in perovskite solar cells because solution-processing produced perovskite film with grain boundary is sensitive to moisture. Herein, we develop a hexamethylenetetramine (HMTA)-mediated one-step solution-processing deposition strategy that leads to the formation of high-purity and grain-boundary-passivation CH3NH3PbI3 film and thereby advances cell optoelectronic performance. Through morphological and structural characterizations and theoretical calculations, we demonstrate that HMTA fully occupies the moisture-exposed surface to build a bridge across grain boundary and coordinates with Pb ions to inhibit the formation of detrimental PbI2. Such HMTA-mediated grown CH3NH3PbI3 films achieves a decent augmentation of power conversion efficiency (PCE) from 12.70% to 17.87%. A full coverage of PbI2-free CH3NH3PbI3 surface on ZnO also boosts the device's stability and reproducibility.

  10. Excessive daytime sleepiness, nocturnal sleep duration and ...

    African Journals Online (AJOL)

    Background and objectives. Short nocturnal sleep duration resulting in sleep debt may be a cause of excessive daytime sleepiness (EDS). Severity of depression (psychopathology) has been found to be directly related to EDS. There is an association between sleep duration and mental health, so there may therefore be an ...

  11. Nocturnal faecal soiling and anal masturbation.

    Science.gov (United States)

    Clark, A F; Tayler, P J; Bhate, S R

    1990-01-01

    Two cases of late onset faecal soiling as a result of anal masturbation in children who were neither mentally handicapped nor psychotic were studied. The role of soiling in aiding the young person and his family to avoid separating and maturing is highlighted. We suggest that the association of anal masturbation and resistant nocturnal soiling may be unrecognised. PMID:2270946

  12. Childhood nocturnal enuresis in the Netherlands

    NARCIS (Netherlands)

    Spee-van der Wekke, J.; Hirasing, R.A.; Meulmeester, J.F.; Radder, J.J.

    1998-01-01

    Objectives. To assess the prevalence of nocturnal enuresis in school children aged 5 to 15 years, and to investigate the association of bedwetting with ethnicity, the educational level of the parents, and the type of education (mainstream or special) received by the child. Methods. Data were

  13. Phytotherapy for children's nocturnal enuresis | Ahmadipour ...

    African Journals Online (AJOL)

    Results have shown that Zingiber officinale, Valeriana officinalis, Alcea rosea, Elettaria cardamomum, Cinnamomum verum, Ribes uva-crispa, Cornus mas, Juglans regia, Vitis vinifera, Sinapis spp., Olea europaea, and Prunus cerasus are a number of important plants that are effective on nocturnal enuresis in traditional ...

  14. Nocturnal Oviposition Behavior of Forensically Important Diptera in Central England.

    Science.gov (United States)

    Barnes, Kate M; Grace, Karon A; Bulling, Mark T

    2015-11-01

    Timing of oviposition on a corpse is a key factor in entomologically based minimum postmortem interval (mPMI) calculations. However, there is considerable variation in nocturnal oviposition behavior of blow flies reported in the research literature. This study investigated nocturnal oviposition in central England for the first time, over 25 trials from 2011 to 2013. Liver-baited traps were placed in an urban location during control (diurnal), and nocturnal periods and environmental conditions were recorded during each 5-h trial. No nocturnal activity or oviposition was observed during the course of the study indicating that nocturnal oviposition is highly unlikely in central England. © 2015 American Academy of Forensic Sciences.

  15. Numerical sensitivity study of the nocturnal low-level jet over a forest canopy and implications for nocturnal surface exchange of carbon dioxide and other trace gases

    DEFF Research Database (Denmark)

    Sogachev, Andrey; Leclerc, M.Y.; Duarte, H.F.

    2010-01-01

    The development of a wind speed maximum in the nocturnal boundary layer, commonly referred to as a low-level jet (LLJ) (Blackadar, 1957), is a common feature of the vertical structure of the atmospheric boundary layer (ABL) and impacts the meteorology and the local climate of a region. A variety...... and are typically intertwined with other contributing factors, they constitute an important cause of jet formation. This mechanism is the only one that can be simulated by one-dimensional atmospheric boundary-layer model. This mechanism is a strong function of the distribution of surface energy properties which...... in turn depends on the time of day, latitude of location, and underlying surface characteristics. These parameters influence the jet height, maximum speed of the jet, and the duration of the wind speed maximum. The present study uses the numerical model SCADIS described by Sogachev et al. (2002) in its...

  16. Nocturnal Polyuria: Excess of Nocturnal Urine Production, Excess of Definitions-Influence on Renal Function Profile.

    Science.gov (United States)

    Goessaert, An-Sofie; Walle, Johan Vande; Bosch, Ruud; Hoebeke, Piet; Everaert, Karel

    2016-03-01

    This study aimed to identify important differences in renal function profile, and potential water and sodium diuresis cutoffs among participants with nocturnal polyuria according to nocturnal polyuria definitions. This post hoc analysis was based on a prospective study in which participants completed a bladder diary, collected urine and provided a blood sample. With an age dependent nocturnal polyuria index greater than 20% to 33% as the referent 4 definitions of nocturnal polyuria were compared, including 1) nocturnal polyuria index greater than 33%, 2) nocturnal urine production greater than 90 ml per hour and 3) greater than 10 ml/kg, and 4) nocturia index greater than 1.5. In 112 male and female participants significant differences in baseline characteristics and bladder diary parameters were found according to definition. Diuresis rate, free water clearance and sodium clearance had similar 24-hour courses in the subgroups with and without polyuria by each definition. The range varied more in the subgroup with vs without polyuria, especially at night for diuresis rate and free water clearance. At night the latter decreased in the polyuria subgroup based on each definition (p polyuria subgroups was found only for urine production greater than 90 ml per hour and polyuria index greater than 20% to 33%. For each definition sodium clearance remained high in the polyuria subgroup, which differed significantly from the no polyuria subgroups (p polyuria by definition. The renal function profile indicating the pathophysiological mechanism of nocturnal polyuria did not seem to be influenced by definition but free water clearance and sodium clearance cutoff sensitivity differed substantially. These results must be confirmed in a larger homogeneous sample. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  17. Body position and late postoperative nocturnal hypoxaemia

    DEFF Research Database (Denmark)

    Rosenberg-Adamsen, S; Stausholm, K; Edvardsen, L

    1997-01-01

    Thirteen patients were monitored for nocturnal body position (supine vs. side) and arterial oxygen saturation pre-operatively and on the second postoperative night after major abdominal surgery. The number of positional changes were significantly decreased after operation (p ... position than on the side (p movements....... towards more time spent in the supine position (p = 0.1). Individual mean arterial oxygen saturation decreased postoperatively (p positions (p = 0.9). Pre-operatively, episodic desaturations were significantly more frequent in the supine...

  18. Niche convergence suggests functionality of the nocturnal fovea

    Directory of Open Access Journals (Sweden)

    Gillian L. Moritz

    2014-07-01

    Full Text Available The fovea is a declivity of the retinal surface associated with maximum visual acuity. Foveae are widespread across vertebrates, but among mammals they are restricted to haplorhine primates (tarsiers, monkeys, apes, and humans, which are primarily diurnal. Thus primates have long contributed to the prevailing view that the fovea is a functional adaptation to diurnal color vision. The foveae of nocturnal taxa, such as tarsiers, are widely interpreted as vestigial traits and therefore evidence of a diurnal ancestry. This enduring premise has been central to adaptive hypotheses on the origins of anthropoid primates; however, the question of whether the fovea of tarsiers is a functionless anachronism or a nocturnal adaptation remains open. To address this question, we focused on the diets of tarsiers (Tarsius and scops owls (Otus, two taxa united by numerous anatomical homoplasies, including foveate vision. A functional interpretation of these homoplasies predicts dietary convergence and competition. This prediction can be tested with an analysis of carbon and nitrogen stable isotopes in tissues, which integrate dietary information. As predicted, the isotopic niches of Tarsius and Otus overlapped. In both Borneo and the Philippines, the δ13C values were indistinguishable, whereas the δ15N values of Otus were marginally higher than those of Tarsius. Our results indicate that both diets consisted mainly of ground-dwelling prey and raise the possibility of some resource partitioning. Taken together, our isotopic analysis supports a functional interpretation of the many homoplasies shared by tarsiers and scops owls, including a retinal fovea. We suggest that the fovea might function similarly in tarsiers and scops owls by calibrating the auditory localization pathway. The integration of auditory localization and visual fixation during prey detection and acquisition might be critical at low light levels.

  19. Radionuclides, stable isotopes, inorganic constituents, and organic compounds in water from selected wells and springs from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman Area, Idaho, 1995

    International Nuclear Information System (INIS)

    Bartholomay, R.C.; Williams, L.M.; Campbell, L.J.

    1996-09-01

    The US Geological Survey and the Idaho Department of Water Resources, in cooperation with the US Department of Energy, sampled 17 sites as part of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area. Water samples were collected and analyzed for selected radionuclides, stable isotopes, inorganic constituents, and organic compounds. The samples were collected from 11 irrigation wells, 2 domestic wells, 2 stock wells, 1 spring, and 1 public-supply well. Two quality assurance samples also were collected and analyzed. None of the radionuclide, inorganic constituents, or organic compound concentrations exceeded the established maximum contaminant levels for drinking water. Many of the radionuclide and inorganic constituent concentrations were greater than their respective reporting levels. All samples analyzed for dissolved organic carbon had concentrations that were greater than the minimum reporting level

  20. Variations in stable hydrogen and oxygen isotopes in atmospheric water vapor in the marine boundary layer across a wide latitude range.

    Science.gov (United States)

    Liu, Jingfeng; Xiao, Cunde; Ding, Minghu; Ren, Jiawen

    2014-11-01

    The newly-developed cavity ring-down laser absorption spectroscopy analyzer with special calibration protocols has enabled the direct measurement of atmospheric vapor isotopes at high spatial and temporal resolution. This paper presents real-time hydrogen and oxygen stable isotope data for atmospheric water vapor above the sea surface, over a wide range of latitudes spanning from 38°N to 69°S. Our results showed relatively higher values of δ(18)O and δ(2)H in the subtropical regions than those in the tropical and high latitude regions, and also a notable decreasing trend in the Antarctic coastal region. By combining the hydrogen and oxygen isotope data with meteoric water line and backward trajectory model analysis, we explored the kinetic fractionation caused by subsiding air masses and related saturated vapor pressure in the subtropics, and the evaporation-driven kinetic fractionation in the Antarctic region. Simultaneous observations of meteorological and marine variables were used to interpret the isotopic composition characteristics and influential factors, indicating that d-excess is negatively correlated with humidity across a wide range of latitudes and weather conditions worldwide. Coincident with previous studies, d-excess is also positively correlated with sea surface temperature and air temperature (Tair), with greater sensitivity to Tair. Thus, atmospheric vapor isotopes measured with high accuracy and good spatial-temporal resolution could act as informative tracers for exploring the water cycle at different regional scales. Such monitoring efforts should be undertaken over a longer time period and in different regions of the world. Copyright © 2014. Published by Elsevier B.V.

  1. Nocturnal bees are attracted by widespread floral scents.

    Science.gov (United States)

    Carvalho, Airton Torres; Maia, Artur Campos Dalia; Ojima, Poliana Yumi; dos Santos, Adauto A; Schlindwein, Clemens

    2012-03-01

    Flower localization in darkness is a challenging task for nocturnal pollinators. Floral scents often play a crucial role in guiding them towards their hosts. Using common volatile compounds of floral scents, we trapped female nocturnal Megalopta-bees (Halictidae), thus uncovering olfactory cues involved in their search for floral resources. Applying a new sampling method hereby described, we offer novel perspectives on the investigation of nocturnal bees.

  2. Measurement of the Flow Over Two Parallel Mountain Ridges in the Nighttime Stable Boundary Layer With Scanning Lidar Systems at the Perdigão 2017 Experiment

    Science.gov (United States)

    Wildmann, N.; Kigle, S.; Gerz, T.; Bell, T.; Klein, P. M.

    2017-12-01

    For onshore wind energy production, the highest wind potential is often found on exposed spots like hilltops, mountain ridges or escarpments with heterogeneous land cover. The understanding of the flow field in such complex terrain in the relevant heights where wind power is generated is an ongoing field of research. The German Aerospace Center (DLR) contributed to the NEWA (New European Wind Atlas) experiment in the province of Perdigão (Portugal) with three long-range Doppler wind lidar of type Leosphere Windcube-200S from May to June 2017. In the experiment, a single wind energy converter (WEC) of type Enercon E82 is situated on a forested mountain ridge. In main wind direction, which is from South-West and almost perpendicular to the ridge, a valley and then a second mountain ridge in a distance of approximately 1.4 km follow. Two of the DLR lidar instruments are placed downstream and in line with the main wind direction and the WEC. One of these instruments is placed in the valley, and the other one on the distant mountain ridge. This line-up allows coplanar scanning of the flow in the valley and over the ridge tops and thus the determination of horizontal and vertical wind components. The third DLR system, placed on the WEC ridge, and an additional scanning lidar from the University of Oklahoma, placed in the valley, are used to determine the cross-wind component of the flow. Regular flow features that were observed with this lidar setup in the six weeks of the intensive operation period are jet-like layers of high wind speeds that occur during the night from a North-Easterly direction. These jets are found to have wind speeds up to 13 m s-1 and are very variable with regards to their maximum speed, height and broadness. Depending on the Froude number of the flow, waves are forming over the two mountain ridges with either a stable wavelength that equals the mountain ridge distance, or more dynamic higher frequency oscillations. All of these flow features are

  3. Low levels of nitryl chloride at ground level: nocturnal nitrogen oxides in the Lower Fraser Valley of British Columbia

    Science.gov (United States)

    Osthoff, Hans D.; Odame-Ankrah, Charles A.; Taha, Youssef M.; Tokarek, Travis W.; Schiller, Corinne L.; Haga, Donna; Jones, Keith; Vingarzan, Roxanne

    2018-05-01

    The nocturnal nitrogen oxides, which include the nitrate radical (NO3), dinitrogen pentoxide (N2O5), and its uptake product on chloride containing aerosol, nitryl chloride (ClNO2), can have profound impacts on the lifetime of NOx ( = NO + NO2), radical budgets, and next-day photochemical ozone (O3) production, yet their abundances and chemistry are only sparsely constrained by ambient air measurements. Here, we present a measurement data set collected at a routine monitoring site near the Abbotsford International Airport (YXX) located approximately 30 km from the Pacific Ocean in the Lower Fraser Valley (LFV) on the west coast of British Columbia. Measurements were made from 20 July to 4 August 2012 and included mixing ratios of ClNO2, N2O5, NO, NO2, total odd nitrogen (NOy), O3, photolysis frequencies, and size distribution and composition of non-refractory submicron aerosol (PM1). At night, O3 was rapidly and often completely removed by dry deposition and by titration with NO of anthropogenic origin and unsaturated biogenic hydrocarbons in a shallow nocturnal inversion surface layer. The low nocturnal O3 mixing ratios and presence of strong chemical sinks for NO3 limited the extent of nocturnal nitrogen oxide chemistry at ground level. Consequently, mixing ratios of N2O5 and ClNO2 were low ( formation of ClNO2 in the nocturnal residual layer aloft than at the surface and the breakup of the nocturnal boundary layer structure in the morning. When quantifiable, production of ClNO2 from N2O5 was efficient and likely occurred predominantly on unquantified supermicron-sized or refractory sea-salt-derived aerosol. After sunrise, production of Cl radicals from photolysis of ClNO2 was negligible compared to production of OH from the reaction of O(1D) + H2O except for a short period after sunrise.

  4. Desmopressin is an effective treatment for mixed nocturia with nocturnal polyuria and decreased nocturnal bladder capacity.

    Science.gov (United States)

    Lee, Hye Won; Choo, Myung-Soo; Lee, Jeong Gu; Park, Choal Hee; Paick, Jae-Seung; Lee, Jeong Zoo; Han, Deok Hyun; Park, Won Hee; Lee, Kyu-Sung

    2010-12-01

    To investigate the efficacy and safety of desmopressin in patients with mixed nocturia, Patients aged ≥ 18 yr with mixed nocturia (≥ 2 voids/night and a nocturnal polyuria index [NPi] >33% and a nocturnal bladder capacity index [NBCi] >1) were recruited. The optimum dose of oral desmopressin was determined during a 3-week dose-titration period and the determined dose was maintained for 4 weeks. The efficacy was assessed by the frequency-volume charts and the sleep questionnaire. The primary endpoint was the proportion of patients with a 50% or greater reduction in the number of nocturnal voids (NV) compared with baseline. Among 103 patients enrolled, 94 (79 men and 15 women) were included in the analysis. The proportion of patients with a 50% or greater reduction in NV was 68 (72%). The mean number of NV decreased significantly (3.20 to 1.34) and the mean nocturnal urine volume, nocturia index, NPi, and NBCi decreased significantly. The mean duration of sleep until the first NV was prolonged from 118.4 ± 44.1 to 220.3 ± 90.7 min (P<0.001). The overall impression of patients about their quality of sleep improved. Adverse events occurred in 6 patients, including one asymptomatic hyponatremia. Desmopressin is an effective and well-tolerated treatment for mixed nocturia.

  5. The effects of adenotonsillotomy on nocturnal enuresis in snoring children

    Directory of Open Access Journals (Sweden)

    Marta Kostrzewa

    2017-12-01

    Full Text Available Introduction: Nocturnal enuresis is a common problem in the paediatric population. A number of reports indicate that there is a relationship between sleep-disordered breathing in children with tonsillar hypertrophy and nocturnal enuresis. Restoration of nasopharyngeal patency may eliminate nocturnal enuresis. Aim: The aim of the study was to evaluate the incidence of nocturnal enuresis in children snoring due to nasopharyngeal lymphatic tissue hypertrophy as well as to assess the effects of restored upper respiratory patency by means of adenectomy and tonsillectomy on the resolution of nocturnal enuresis in children. Material and methods: The study included 50 children with sleep-disordered breathing qualified for adenectomy, tonsillotomy or adenotonsillotomy (median age 7 years. The control group consisted of 20 healthy children (median age 8 years. Children in the study group were assessed prior to surgical procedure as well as 3 and 6 months after surgery. The presence of sleep-disordered breathing and nocturnal enuresis was determined based on author’s questionnaire completed by parents. Results: The incidence of nocturnal enuresis in children with nasopharyngeal lymphatic tissue hypertrophy was 18% (M:F 17%:19%; p > 0.05. Nocturnal enuresis was still reported in 6% of children 3 months after tonsillotomy. The disorder resolved in all girls and 97% of boys 6 months after procedure. Conclusions: Sleep-disordered breathing in children with nasopharyngeal lymphatic tissue hypertrophy is associated with nocturnal enuresis. Restoration of nasopharyngeal patency in these patients eliminates nocturnal enuresis. Tonsillar hypertrophy causing obstructive breathing should be included in the differential diagnosis of nocturnal enuresis.

  6. Early dinner reduces nocturnal gastric acidity.

    OpenAIRE

    Duroux, P; Bauerfeind, P; Emde, C; Koelz, H R; Blum, A L

    1989-01-01

    This study examines whether eating food at different times has differential effects on intragastric pH. Experiments were done in 23 healthy volunteers (12 men). Intragastric acidity was monitored by ambulatory 22 hour pH-metry. Composition of meals was standardised: breakfast and lunch at 7 am and 12 noon respectively, and dinner at 6 or 9 pm, in random order. The time of going to bed and getting up was also standardised. With early dinner nocturnal pH was higher, than with late dinner (pH me...

  7. Association between nocturnal bruxism and gastroesophageal reflux.

    Science.gov (United States)

    Miyawaki, Shouichi; Tanimoto, Yuko; Araki, Yoshiko; Katayama, Akira; Fujii, Akihito; Takano-Yamamoto, Teruko

    2003-11-01

    To examine the relationship between nocturnal bruxism and gastroesophageal reflux. Controlled descriptive study and double-blind, placebo-controlled, clinical study. Portable pH monitoring, electromyography, and audio-video recordings were conducted during the night in the subjects' home. Ten patients with bruxism and 10 normal subjects were matched for height, weight, age, and sex. They did not have symptoms of gastroesophageal reflux disease. Medication with a proton pump inhibitor (ie, a gastric-acid-inhibiting drug). The bruxism group showed a significantly higher frequency of nocturnal rhythmic masticatory muscle activity (RMMA) episodes (mean +/- SD: 6.7 +/- 2.2 times per hour) and a higher frequency and percentage of time of gastroesophageal reflux episodes with a pH less than 4.0 and 5.0 (0.5 +/- 0.9 and 3.6 +/- 1.6 times per hour and 1.3% +/- 2.5% and 7.4% +/- 12.6%, respectively) than the control group (RMMA episodes: 2.4 +/- 0.9 times per hour; gastroesophageal reflux episodes: 0.0 +/- 0.0 and 0.1 +/- 0.3 times per hour and 0.0% +/- 0.0% and 0.0% +/- 0.0%, respectively). In the bruxism group, 100% of the gastroesophageal reflux episodes with a pH less than 3.0 and 4.0 included both an RMMA episode and an electromyographic burst, the duration of which was approximately 0.5 to 1.0 seconds, probably representing swallowing of saliva. The majority of gastroesophageal reflux episodes with a pH of 4.0 to 5.0 also included both an RMMA episode and an electromyographic burst in the control and bruxism groups (100% +/- 0.0% vs 70.7% +/- 16.5%), again probably due to swallowing of saliva. The remaining minority of gastroesophageal reflux episodes with a pH of 4.0 to 5.0 contained only an electromyographic burst (swallowing of saliva). The frequency of RMMA episodes after the release of the medication from the proton pump inhibitor, which increased the gastric and esophageal pH, was significantly lower than that after administration of the placebo in the control

  8. Wintertime Boundary Layer Structure in the Grand Canyon.

    Science.gov (United States)

    Whiteman, C. David; Zhong, Shiyuan; Bian, Xindi

    1999-08-01

    Wintertime temperature profiles in the Grand Canyon exhibit a neutral to isothermal stratification during both daytime and nighttime, with only rare instances of actual temperature inversions. The canyon warms during daytime and cools during nighttime more or less uniformly through the canyon's entire depth. This weak stability and temperature structure evolution differ from other Rocky Mountain valleys, which develop strong nocturnal inversions and exhibit convective and stable boundary layers that grow upward from the valley floor. Mechanisms that may be responsible for the different behavior of the Grand Canyon are discussed, including the possibility that the canyon atmosphere is frequently mixed to near-neutral stratification when cold air drains into the top of the canyon from the nearby snow-covered Kaibab Plateau. Another feature of canyon temperature profiles is the sharp inversions that often form near the canyon rims. These are generally produced when warm air is advected over the canyon in advance of passing synoptic-scale ridges.Wintertime winds in the main canyon are not classical diurnal along-valley wind systems. Rather, they are driven along the canyon axis by the horizontal synoptic-scale pressure gradient that is superimposed along the canyon's axis by passing synoptic-scale weather disturbances. They may thus bring winds into the canyon from either end at any time of day.The implications of the observed canyon boundary layer structure for air pollution dispersion are discussed.

  9. An Improved Iterative Fitting Method to Estimate Nocturnal Residual Layer Height

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2016-08-01

    Full Text Available The planetary boundary layer (PBL is an atmospheric region near the Earth’s surface. It is significant for weather forecasting and for the study of air quality and climate. In this study, the top of nocturnal residual layers—which are what remain of the daytime mixing layer—are estimated by an elastic backscatter Lidar in Wuhan (30.5°N, 114.4°E, a city in Central China. The ideal profile fitting method is widely applied to determine the nocturnal residual layer height (RLH from Lidar data. However, the method is seriously affected by an optical thick layer. Thus, we propose an improved iterative fitting method to eliminate the optical thick layer effect on RLH detection using Lidar. Two typical case studies observed by elastic Lidar are presented to demonstrate the theory and advantage of the proposed method. Results of case analysis indicate that the improved method is more practical and precise than profile-fitting, gradient, and wavelet covariance transform method in terms of nocturnal RLH evaluation under low cloud conditions. Long-term observations of RLH performed with ideal profile fitting and improved methods were carried out in Wuhan from 28 May 2011 to 17 June 2016. Comparisons of Lidar-derived RLHs with the two types of methods verify that the improved solution is practical. Statistical analysis of a six-year Lidar signal was conducted to reveal the monthly average values of nocturnal RLH in Wuhan. A clear RLH monthly cycle with a maximum mean height of about 1.8 km above ground level was observed in August, and a minimum height of about 0.7 km was observed in January. The variation in monthly mean RLH displays an obvious quarterly dependence, which coincides with the annual variation in local surface temperature.

  10. Increased nocturnal blood pressure in enuretic children with polyuria.

    Science.gov (United States)

    Kruse, Anne; Mahler, Birgitte; Rittig, Soren; Djurhuus, Jens Christian

    2009-10-01

    We investigated the association between nocturnal blood pressure and urine production in children with enuresis. A total of 39 consecutive children with a mean age of 9.8 years (range 6.2 to 14.9) with monosymptomatic nocturnal enuresis completed a bladder diary, including 2 weeks of basic documentation and 2 with desmopressin titration from 120 to 240 microg sublingually. Arterial blood pressure was measured every 30 minutes during 24 hours and during 4 additional nights using an ambulatory blood pressure monitor. Furthermore, 10 healthy children were recruited into the study who completed a bladder diary for 5 days while measuring arterial blood pressures with documentation of all intake and voided volumes. Patients with nocturnal polyuria had significantly higher nocturnal mean arterial pressure than patients without polyuria and controls (p polyuria than in children without polyuria. There was a significant positive correlation between average nocturnal mean arterial pressure and nocturnal urine volume in the whole study. The association between nocturnal blood pressure and urine volume, and the role of blood pressure should be investigated in a larger group of children with enuresis who have nocturnal polyuria.

  11. Understanding nocturnal enuresis and its treatments.

    Science.gov (United States)

    Potter, D C; Wogoman, H A; Nietch, P

    1999-09-01

    Nocturnal enuresis is a condition that touches the lives of many children around the world. Affected children and their parents may experience feelings of guilt, frustration, and anxiety because of their lack of control over the situation. Nurses can play an important role in providing education to families in regards to the causes and treatment of enuresis. It is important for nurses to understand the problem of bedwetting thoroughly so they can assist the family in making an informed decision about the various options currently available. Nocturnal enuresis (bedwetting) is a common disorder that frequently results in frustration and stress on not only the children that experience it, but their parents as well. Scharf, Pravda, Jennings, Kauffman, and Ringel (1987) note that an estimated five to seven million children in America experience enuresis. Enuresis has family and psychosocial aspects, along with financial concerns. Therefore, it is important for nurses to be aware of the causes of enuresis, how it affects the family, and the current treatments that are available.

  12. Artificial light and nocturnal activity in gammarids

    Directory of Open Access Journals (Sweden)

    Elizabeth K. Perkin

    2014-03-01

    Full Text Available Artificial light is gaining attention as a potential stressor to aquatic ecosystems. Artificial lights located near streams increase light levels experienced by stream invertebrates and we hypothesized light would depress night drift rates. We also hypothesized that the effect of light on drift rates would decrease over time as the invertebrates acclimated to the new light level over the course of one month’s exposure. These hypotheses were tested by placing Gammarus spp. in eight, 75 m × 1 m artificial flumes. One flume was exposed to strong (416 lx artificial light at night. This strong light created a gradient between 4.19 and 0.04 lx over the neighboring six artificial flumes, while a control flume was completely covered with black plastic at night. Night-time light measurements taken in the Berlin area confirm that half the flumes were at light levels experienced by urban aquatic invertebrates. Surprisingly, no light treatment affected gammarid drift rates. In contrast, physical activity measurements of in situ individually caged G. roeseli showed they increased short-term activity levels in nights of complete darkness and decreased activity levels in brightly lit flumes. Both nocturnal and diurnal drift increased, and day drift rates were unexpectadly higher than nocturnal drift.

  13. Endurance performance and nocturnal HRV indices.

    Science.gov (United States)

    Nummela, A; Hynynen, E; Kaikkonen, P; Rusko, H

    2010-03-01

    The effects of endurance training on endurance performance characteristics and cardiac autonomic modulation during night sleep were investigated. Twenty-four sedentary subjects trained over four weeks two hours per week at an average running intensity of 76+/-4% of their heart rate reserve. The R to R ECG-intervals were recorded and heart rate variability indices including high frequency power (HFP) were calculated for the nights following the training days every week. The subjects were divided into responders and non-responders according to the improvements in the maximal velocity of the incremental treadmill test (v(max)). The responders improved their v(max) by 10.9+/-46 % (p < 0.001) while no changes were observed in the non-responders (1.6+/-3.0%), although there were no differences in any training load variables between the groups. In the responders nocturnal HFP was significantly higher during the fourth training week compared to the first training week (p=0.036). Furthermore, a significant correlation was observed between the change in v(max) and the change in nocturnal HFP (r=0.482, p=0.042). It was concluded that after similar training, an increase in cardiac vagal modulation was related to improved v(max) in the sedentary subjects. Georg Thieme Verlag KG Stuttgart.New York.

  14. Nocturnal Hypertension and Attenuated Nocturnal Blood Pressure Dipping is Common in Pediatric Lupus

    Science.gov (United States)

    Campbell, J. Fallon; Swartz, Sarah J.; Wenderfer, Scott E.

    2015-01-01

    Hypertension is an important manifestation of systemic lupus erythematosus (SLE) but reports of prevalence vary between 20-70% in published reports of adult and pediatric patients. For both children and adults with SLE, the clinical diagnosis and management of hypertension has traditionally been based on guidelines developed for the general population. In clinical trials, the criteria used for defining participants with hypertension are mostly undefined. As a first step towards formally assessing the blood pressure (BP) patterns of children diagnosed with SLE, 24-hr ambulatory BP monitoring data was analyzed on clinic patients who presented with prehypertension or stage I hypertension. In this pediatric SLE cohort (n=10), 20% met daytime criteria for a diagnosis of hypertension. Patterns of BP elevation varied widely with white coat, masked, isolated systolic, and diastolic nocturnal hypertension all identified. Nocturnal hypertension was detected in 60% and attenuated nocturnal BP dipping in 90% of both hypertensive and normotensive SLE patients. In SLE patients, the median nighttime systolic and diastolic loads were 25% and 15.5% compared with median daily loads of 12.5% and 11.5%. Daytime and nighttime systolic and diastolic BP load and nocturnal dipping was compared to a control population consisting of 85 non-SLE patients under 21 years old with prehypertension or stage 1 hypertension presenting to hypertension clinic. Median systolic BP dipped 5.3 mmHg in SLE patients compared to 11.9 mmHg in non-lupus ( p-value = 0.001). Median diastolic BP dipped 12.9 mmHg versus 18.5 mmHg in non-lupus ( p-value = 0.003). Patterns of BP dysregulation in pediatric SLE merit further exploration. Children with or without SLE displaying prehypertensive or stage 1 casual BP measurements had similar rates of hypertension by ambulatory BP monitoring. However, regardless of BP diagnosis, and independent of kidney involvement, there was an increased proportion with attenuated

  15. Vertical profiles of nitrous acid in the nocturnal urban atmosphere of Houston, TX

    Directory of Open Access Journals (Sweden)

    K. W. Wong

    2011-04-01

    Full Text Available Nitrous acid (HONO often plays an important role in tropospheric photochemistry as a major precursor of the hydroxyl radical (OH in early morning hours and potentially during the day. However, the processes leading to formation of HONO and its vertical distribution at night, which can have a considerable impact on daytime ozone formation, are currently poorly characterized by observations and models. Long-path differential optical absorption spectroscopy (LP-DOAS measurements of HONO during the 2006 TexAQS II Radical and Aerosol Measurement Project (TRAMP, near downtown Houston, TX, show nocturnal vertical profiles of HONO, with mixing ratios of up to 2.2 ppb near the surface and below 100 ppt aloft. Three nighttime periods of HONO, NO2 and O3 observations during TRAMP were used to perform model simulations of vertical mixing ratio profiles. By adjusting vertical mixing and NOx emissions the modeled NO2 and O3 mixing ratios showed very good agreement with the observations.

    Using a simple conversion of NO2 to HONO on the ground, direct HONO emissions, as well as HONO loss at the ground and on aerosol, the observed HONO profiles were reproduced by the model for 1–2 and 7–8 September in the nocturnal boundary layer (NBL. The unobserved increase of HONO to NO2 ratio (HONO/NO2 with altitude that was simulated by the initial model runs was found to be due to HONO uptake being too small on aerosol and too large on the ground. Refined model runs, with adjusted HONO uptake coefficients, showed much better agreement of HONO and HONO/NO2 for two typical nights, except during morning rush hour, when other HONO formation pathways are most likely active. One of the nights analyzed showed an increase of HONO mixing ratios together with decreasing NO2 mixing ratios that the model was unable to reproduce, most likely due to the impact of

  16. Surface Layer Processes And Nocturnal Low Level Jet Development--An Observational Study During Pecan

    Science.gov (United States)

    2016-12-01

    temperature was measured at -0.05m, -0.10m, and -0.25m and soil moisture at -0.10m and -0.25m. Shortwave solar irradiance and exitance measurements and...evolution, as found in the second column. This quantity is intended to serve as a measurement of the relative intensity of the LLJ wind maximum to a... measure of turbulence intensity relative to the ambient mean 6 m wind speed during the afternoon hours prior to the onset of the stable nocturnal

  17. Radionuclides, stable isotopes, inorganic constituents, and organic compounds in water from selected wells and springs from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area, Idaho, 1993

    Science.gov (United States)

    Bartholomay, Roy C.; Edwards, Daniel D.; Campbell, Linford J.

    1994-01-01

    The U.S. Geological Survey and the Idaho Department of Water Resources, in response to a request from the U.S. Department of Energy, sampled 19 sites as part of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area. Water samples were collected and analyzed for selected radionuclides, stable isotopes, inorganic constituents, and organic compounds. The samples were collected from seven irrigation wells, four domestic wells, two springs, one stock well, three dairy wells, one observation well, and one commercial well. Two quality assurance samples also were collected and analyzed. None of the radionuclides, inorganic constituents, or organic compounds exceeded the established maximum contaminant levels for drinking water. Most of the radionuclide and inorganic constituent concen- trations exceeded their respective laboratory reporting levels. All samples analyzed for surfactants and dissolved organic carbon had concentrations that exceeded their reporting level. Ethylbenzene concentrations exceeded the reporting level in one water sample.

  18. Nocturnal Eating: Association with Binge Eating, Obesity, and Psychological Distress

    Science.gov (United States)

    Striegel-Moore, Ruth H.; Rosselli, Francine; Wilson, G. Terence; Perrin, Nancy; Harvey, Kate; DeBar, Lynn

    2009-01-01

    Objective To examine clinical correlates of nocturnal eating, a core behavioral symptom of night eating syndrome. Method Data from 285 women who had participated in a two-stage screening for binge eating were utilized. Women (n = 41) who reported one or more nocturnal eating episodes in the past 28 days on the Eating Disorder Examination and women who did not report nocturnal eating (n =244) were compared on eating disorder symptomatology, Body Mass Index (BMI), and on measures of psychosocial adjustment. Results Nocturnal eaters were significantly more likely to report binge eating and differed significantly from non-nocturnal eaters (with responses indicating greater disturbance) on weight and shape concern, eating concern, self-esteem, depression, and functional impairment, but not on BMI or dietary restraint. Group differences remained significant in analyses adjusting for binge eating. Conclusions This study confirms the association between nocturnal eating and binge eating previously found in treatment seeking samples yet also suggests that the elevated eating disorder symptoms and decreased psychosocial adjustment observed in nocturnal eaters is not simply a function of binge eating. PMID:19708071

  19. Nocturnal enuresis in india: Are we diagnosing and managing correctly?

    Directory of Open Access Journals (Sweden)

    N M Reddy

    2017-01-01

    Full Text Available Nocturnal enuresis is a common problem affecting school-aged children worldwide. Although it has significant impact on child's psychology, it is always under-recognized in India and considered as a condition which will outgrow with advancing age. Nocturnal enuresis classified as primary or secondary and monosymptomatic or nonmonosymptomatic. Factors that cause enuresis include genetic factors, bladder dysfunction, psychological factors, and inappropriate antidiuretic hormone secretion, leading to nocturnal polyuria. Diagnosis consists of detailed medical history, clinical examination, frequency-volume charts, and appropriate investigations. The frequency-volume chart or voiding diary helps in establishing diagnosis and tailoring therapy. The first step in treating nocturnal enuresis is to counsel the parents and the affected child about the condition and reassure them that it can be cured. One of the effective strategies to manage enuresis is alarm therapy, but currently, it is not easily available in India. Desmopressin has been used in the treatment of nocturnal enuresis for close to 50 years. It provides an effective and safe option for the management of nocturnal enuresis. This review covers the diagnosis and management of nocturnal enuresis and introduces the concept of “bedwetting clinics” in India, which should help clinicians in the thorough investigation of bedwetting cases.

  20. Nocturnal Gastroesophageal Reflux Revisited by Impedance-pH Monitoring

    Science.gov (United States)

    Blondeau, Kathleen; Mertens, Veerle; Tack, Jan; Sifrim, Daniel

    2011-01-01

    Background/Aims Impedance-pH monitoring allows detailed characterization of gastroesophageal reflux and esophageal activity associated with reflux. We assessed the characteristics of nocturnal reflux and esophageal activity preceding and following reflux. Methods Impedance-pH tracings from 11 healthy subjects and 76 patients with gastroesophageal reflux disease off acid-suppressive therapy were analyzed. Characteristics of nocturnal supine reflux, time distribution and esophageal activity seen on impedance at 2 minute intervals preceding and following reflux were described. Results Patients had more nocturnal reflux events than healthy subjects (8 [4-12] vs 2 [1-5], P = 0.002), with lower proportion of weakly acidic reflux (57% [35-78] vs 80% [60-100], P = 0.044). Nocturnal reflux was mainly liquid (80%) and reached the proximal esophagus more often in patients (6% vs 0%, P = 0.047). Acid reflux predominated in the first 2 hours (66%) and weakly acidic reflux in the last 3 hours (70%) of the night. Most nocturnal reflux was preceded by aboral flows and cleared by short lasting volume clearance. In patients, prolonged chemical clearance was associated with less esophageal activity. Conclusions Nocturnal weakly acidic reflux is as common as acid reflux in patients with gastroesophageal reflux disease, and predominates later in the night. Impedance-pH can predict prolonged chemical clearance after nocturnal acid reflux. PMID:21602991

  1. Pathophysiology of nocturnal lower urinary tract symptoms in older patients with urinary incontinence.

    Science.gov (United States)

    Denys, Marie-Astrid; Decalf, Veerle; Kumps, Candy; Petrovic, Mirko; Goessaert, An-Sofie; Everaert, Karel

    2017-11-01

    To explore the mismatch between functional bladder capacity and nocturnal urine production, and to study the pathophysiology of an increased nocturnal urine production in older patients with urinary incontinence. The present prospective observational study included adults aged ≥65 years with urinary incontinence. Participants completed questionnaires, frequency volume charts and renal function profiles. The nocturnal lower urinary tract symptom index was defined as nocturnal urine output/maximum voided volume; the nocturnal polyuria index as nocturnal/24 h urine output. The median age (n = 95) was 74 years (69-79), 87% were women and 73% had nocturnal lower urinary tract symptoms (nocturnal urinary incontinence or nocturia ≥2). Participants with nocturnal lower urinary tract symptoms had a significantly higher nocturnal urine output (809 mL vs 650 mL; P = 0.001) and no significant difference in maximum voided volume (350 mL vs 437 mL; P = 0.079) compared with participants without nocturnal lower urinary tract symptoms. Participants (nocturnal polyuria index >33% [n = 56], nocturnal polyuria index >40% [n = 42], nocturnal lower urinary tract symptom index >1.87 [n = 51]) showed higher night-time diuresis rates, free water and sodium clearance compared with during the daytime. Controls (nocturnal polyuria index ≤33% [n = 26], nocturnal polyuria index ≤40% [n = 40], nocturnal lower urinary tract symptom index ≤1.87 [n = 44]) had no circadian rhythm in their diuresis rate or sodium clearance, but more nocturnal free water clearance compared with during the daytime. The majority of older adults with urinary incontinence present nocturnal lower urinary tract symptoms. An increased nocturnal sodium diuresis seems to be the only mechanism differentiating patients with nocturnal lower urinary tract symptoms from controls. © 2017 The Japanese Urological Association.

  2. Green Light for Nocturnally Migrating Birds

    Directory of Open Access Journals (Sweden)

    Hanneke Poot

    2008-12-01

    Laboratory experiments have shown the magnetic compass to be wavelength dependent: migratory birds require light from the blue-green part of the spectrum for magnetic compass orientation, whereas red light (visible long-wavelength disrupts magnetic orientation. We designed a field study to test if and how changing light color influenced migrating birds under field conditions. We found that nocturnally migrating birds were disoriented and attracted by red and white light (containing visible long-wavelength radiation, whereas they were clearly less disoriented by blue and green light (containing less or no visible long-wavelength radiation. This was especially the case on overcast nights. Our results clearly open perspective for the development of bird-friendly artificial lighting by manipulating wavelength characteristics. Preliminary results with an experimentally developed bird-friendly light source on an offshore platform are promising. What needs to be investigated is the impact of bird-friendly light on other organisms than birds.

  3. Behavioral alarm treatment for nocturnal enuresis

    Directory of Open Access Journals (Sweden)

    Rodrigo F. Pereira

    2010-06-01

    Full Text Available PURPOSES: To investigate the efficacy of alarm treatment in a sample of Brazilian children and adolescents with nocturnal enuresis and relate treatment success to age and type of clinical support. MATERIALS AND METHODS: During 32 weeks, 84 children and adolescents received alarm treatment together with weekly psychological support sessions for individual families or groups of 5 to 10 families. RESULTS: 71% of the participants achieved success, defined as 14 consecutive dry nights. The result was similar for children and adolescents and for individual or group support. The time until success was shorter for participants missing fewer support sessions. CONCLUSIONS: Alarm treatment was effective for the present sample, regardless of age or type of support. Missing a higher number of support sessions, which may reflect low motivation for treatment, increased the risk of failure.

  4. Clinical correlation between hypercalciuria and nocturnal enuresis

    Directory of Open Access Journals (Sweden)

    Ehsan Valavi

    2011-01-01

    Full Text Available Hypercalciuria may present with dysuria, urinary incontinence and nocturnal enuresis (NE. To determine the frequency of hypercalciuria in NE patients and normally continent children, we studied 122 consecutive pre- school children with NE referred to our nephrology clinic during two years, from September 2007 to August 2009. We measured the 24- hour urinary calcium. Furthermore, we compared the response to nasal desmopressin in hypercalciuric and normocalciuric patients. Hypercalciuria was found in 26 (21.3 % of the NE patients as compared with five (4.5% of 110 continent children [(P 0.05. The response to desmopressin above 90% occurred within one month of therapy without a significant change in the levels of hypercalciuria. We conclude that these results suggest that hypercalciuria has a significant association with NE and does not interfere with the desmopressin therapy.

  5. Extended driving impairs nocturnal driving performances.

    Directory of Open Access Journals (Sweden)

    Patricia Sagaspe

    Full Text Available Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3-5 am, 1-5 am and 9 pm-5 am on open highway. Fourteen young healthy men (mean age [+/-SD] = 23.4 [+/-1.7] years participated Inappropriate line crossings (ILC in the last hour of driving of each session, sleep variables, self-perceived fatigue and sleepiness were measured. Compared to the short (3-5 am driving session, the incidence rate ratio of inappropriate line crossings increased by 2.6 (95% CI, 1.1 to 6.0; P<.05 for the intermediate (1-5 am driving session and by 4.0 (CI, 1.7 to 9.4; P<.001 for the long (9 pm-5 am driving session. Compared to the reference session (9-10 pm, the incidence rate ratio of inappropriate line crossings were 6.0 (95% CI, 2.3 to 15.5; P<.001, 15.4 (CI, 4.6 to 51.5; P<.001 and 24.3 (CI, 7.4 to 79.5; P<.001, respectively, for the three different durations of driving. Self-rated fatigue and sleepiness scores were both positively correlated to driving impairment in the intermediate and long duration sessions (P<.05 and increased significantly during the nocturnal driving sessions compared to the reference session (P<.01. At night, extended driving impairs driving performances and therefore should be limited.

  6. Comparative Effects of an Angiotensin II Receptor Blocker (ARB)/Diuretic vs. ARB/Calcium-Channel Blocker Combination on Uncontrolled Nocturnal Hypertension Evaluated by Information and Communication Technology-Based Nocturnal Home Blood Pressure Monitoring - The NOCTURNE Study.

    Science.gov (United States)

    Kario, Kazuomi; Tomitani, Naoko; Kanegae, Hiroshi; Ishii, Hajime; Uchiyama, Kazuaki; Yamagiwa, Kayo; Shiraiwa, Toshihiko; Katsuya, Tomohiro; Yoshida, Tetsuro; Kanda, Kiyomi; Hasegawa, Shinji; Hoshide, Satoshi

    2017-06-23

    Nocturnal blood pressure (BP) is an independent risk factor of cardiovascular events. The NOCTURNE study, a multicenter, randomized controlled trial (RCT) using our recently developed information and communication technology (ICT) nocturnal home BP monitoring (HBPM) device, was performed to compare the nocturnal HBP-lowering effects of differential ARB-based combination therapies in 411 Japanese patients with nocturnal hypertension (HT).Methods and Results:Patients with nocturnal BP ≥120/70 mmHg at baseline even under ARB therapy (100 mg irbesartan daily) were enrolled. The ARB/CCB combination therapy (irbesartan 100 mg+amlodipine 5 mg) achieved a significantly greater reduction in nocturnal home systolic BP (primary endpoint) than the ARB/diuretic combination (daily irbesartan 100 mg+trichlormethiazide 1 mg) (-14.4 vs. -10.5 mmHg, P<0.0001), independently of urinary sodium excretion and/or nocturnal BP dipping status. However, the change in nocturnal home systolic BP was comparable among the post-hoc subgroups with higher salt sensitivity (diabetes, chronic kidney disease, and elderly patients). This is the first RCT demonstrating the feasibility of clinical assessment of nocturnal BP by ICT-nocturnal HBPM. The ARB/CCB combination was shown to be superior to ARB/diuretic in patients with uncontrolled nocturnal HT independently of sodium intake, despite the similar impact of the 2 combinations in patients with higher salt sensitivity.

  7. Low levels of nitryl chloride at ground level: nocturnal nitrogen oxides in the Lower Fraser Valley of British Columbia

    Directory of Open Access Journals (Sweden)

    H. D. Osthoff

    2018-05-01

    Full Text Available The nocturnal nitrogen oxides, which include the nitrate radical (NO3, dinitrogen pentoxide (N2O5, and its uptake product on chloride containing aerosol, nitryl chloride (ClNO2, can have profound impacts on the lifetime of NOx ( =  NO + NO2, radical budgets, and next-day photochemical ozone (O3 production, yet their abundances and chemistry are only sparsely constrained by ambient air measurements.Here, we present a measurement data set collected at a routine monitoring site near the Abbotsford International Airport (YXX located approximately 30 km from the Pacific Ocean in the Lower Fraser Valley (LFV on the west coast of British Columbia. Measurements were made from 20 July to 4 August 2012 and included mixing ratios of ClNO2, N2O5, NO, NO2, total odd nitrogen (NOy, O3, photolysis frequencies, and size distribution and composition of non-refractory submicron aerosol (PM1.At night, O3 was rapidly and often completely removed by dry deposition and by titration with NO of anthropogenic origin and unsaturated biogenic hydrocarbons in a shallow nocturnal inversion surface layer. The low nocturnal O3 mixing ratios and presence of strong chemical sinks for NO3 limited the extent of nocturnal nitrogen oxide chemistry at ground level. Consequently, mixing ratios of N2O5 and ClNO2 were low ( <  30 and  <  100 parts-per-trillion by volume (pptv and median nocturnal peak values of 7.8 and 7.9 pptv, respectively. Mixing ratios of ClNO2 frequently peaked 1–2 h after sunrise rationalized by more efficient formation of ClNO2 in the nocturnal residual layer aloft than at the surface and the breakup of the nocturnal boundary layer structure in the morning. When quantifiable, production of ClNO2 from N2O5 was efficient and likely occurred predominantly on unquantified supermicron-sized or refractory sea-salt-derived aerosol. After sunrise, production of Cl radicals from photolysis of ClNO2 was negligible compared to production of OH

  8. Stable isotopes

    International Nuclear Information System (INIS)

    Evans, D.K.

    1986-01-01

    Seventy-five percent of the world's stable isotope supply comes from one producer, Oak Ridge Nuclear Laboratory (ORNL) in the US. Canadian concern is that foreign needs will be met only after domestic needs, thus creating a shortage of stable isotopes in Canada. This article describes the present situation in Canada (availability and cost) of stable isotopes, the isotope enrichment techniques, and related research programs at Chalk River Nuclear Laboratories (CRNL)

  9. Influence of Frequent Nocturnal Home Hemodialysis on Food Preference

    NARCIS (Netherlands)

    Ipema, Karin; Franssen, Casper; van der Schans, Cees; Smit, Lianne; Noordman, Sabine; Haisma, Hinke

    Objective: Dialysis patients frequently report a change of taste that is reversible after renal transplantation, suggesting that uremic toxins may negatively influence taste. Currently, frequent nocturnal home hemodialysis (NHHD) is the most effective method of hemodialysis, and is associated with

  10. Genetics Home Reference: autosomal dominant nocturnal frontal lobe epilepsy

    Science.gov (United States)

    ... with ADNFLE have experienced psychiatric disorders (such as schizophrenia), behavioral problems, or intellectual disability. It is unclear ... Epilepsy Society Citizens United for Research in Epilepsy (CURE) GeneReviews (1 link) Autosomal Dominant Nocturnal Frontal Lobe ...

  11. Sibelius: Luonnotar. Chevauchee nocturne et lever du soleil / Pierre Gervasoni

    Index Scriptorium Estoniae

    Gervasoni, Pierre

    1996-01-01

    Uuest heliplaadist "Sibelius: Luonnotar. Chevauchee nocturne et lever du soleil. 4 Legendes. Orchestre Philharmonique Royal de Stockholm, Paavo Järvi. Virgin Classics 545 213-2 (CD:167F). 1996. TT: 1h 13'22"

  12. Temporal Relationships Between Napping and Nocturnal Sleep in Healthy Adolescents.

    Science.gov (United States)

    Jakubowski, Karen P; Hall, Martica H; Lee, Laisze; Matthews, Karen A

    2017-01-01

    Many adolescents do not achieve the recommended 9 hr of sleep per night and report daytime napping, perhaps because it makes up for short nocturnal sleep. This article tests temporal relationships between daytime naps and nighttime sleep as measured by actigraphy and diary among 236 healthy high school students during one school week. Mixed model analyses adjusted for age, race, and gender demonstrated that shorter actigraphy-assessed nocturnal sleep duration predicted longer napping (measured by actigraphy and diary) the next day. Napping (by actigraphy and diary) predicted shorter nocturnal sleep duration and worse sleep efficiency that night measured by actigraphy. Diary-reported napping also predicted poorer self-reported sleep quality that night. Frequent napping may interfere with nocturnal sleep during adolescence.

  13. Pattern of Primary Nocturnal Enuresis in Primary School Children ...

    African Journals Online (AJOL)

    Pattern of Primary Nocturnal Enuresis in Primary School Children (First Grade) in ... The control group consisting of 100 age-matched non-enuretic children ... was insignificantly associated with a positive family history, family size or birth rank.

  14. The complement inhibitor eculizumab in paroxysmal nocturnal hemoglobinuria.

    NARCIS (Netherlands)

    Hillmen, P.; Young, N.S.; Schubert, J.; Brodsky, R.A.; Socie, G.; Muus, P.; Roth, A.; Szer, J.; Elebute, M.O.; Nakamura, R.; Browne, P.; Risitano, A.M.; Hill, A.; Schrezenmeier, H.; Fu, C.L.; Maciejewski, J; Rollins, S.A.; Mojcik, C.F.; Rother, R.P.; Luzzatto, L.

    2006-01-01

    BACKGROUND: We tested the safety and efficacy of eculizumab, a humanized monoclonal antibody against terminal complement protein C5 that inhibits terminal complement activation, in patients with paroxysmal nocturnal hemoglobinuria (PNH). METHODS: We conducted a double-blind, randomized,

  15. Hearing is not necessarily believing in nocturnal anurans

    OpenAIRE

    Richardson, Christina; Gomez, Doris; Durieux, Romain; Théry, Marc; Joly, Pierre; Léna, Jean-Paul; Plénet, Sandrine; Lengagne, Thierry

    2010-01-01

    The recent discovery of the use of visual cues for mate choice by nocturnal acoustic species raises the important, and to date unaddressed, question of how these signals affect the outcome of mate choice predicted by female preference for male calls. In order to address this question, we presented female Hyla arborea tree frogs with a series of choices between combinations of acoustic and visual cues of varying quality in nocturnal conditions. While females exhibited the expected preference f...

  16. Planetary Boundary Layer Dynamics over Reno, Nevada in Summer

    Science.gov (United States)

    Liming, A.; Sumlin, B.; Loria Salazar, S. M.; Holmes, H.; Arnott, W. P.

    2014-12-01

    Quantifying the height of the planetary boundary layer (PBL) is important to understand the transport behavior, mixing, and surface concentrations of air pollutants. In Reno, NV, located in complex, mountainous terrain with high desert climate, the daytime boundary layer can rise to an estimated 3km or more on a summer day due to surface heating and convection. The nocturnal boundary layer, conversely, tends to be much lower and highly stable due to radiative cooling from the surface at night and downslope flow of cool air from nearby mountains. With limited availability of radiosonde data, current estimates of the PBL height at any given time or location are potentially over or underestimated. To better quantify the height and characterize the PBL physics, we developed portable, lightweight sensors that measure CO2 concentrations, temperature, pressure, and humidity every 5 seconds. Four of these sensors are used on a tethered balloon system to monitor CO2 concentrations from the surface up to 300m. We will combine this data with Radio Acoustic Sounding System (RASS) data that measures vertical profiles of wind speed, temperature, and humidity from 40m to 400m. This experiment will characterize the diurnal evolution of CO2 concentrations at multiple heights in the PBL, provide insight into PBL physics during stability transition periods at sunrise and sunset, and estimate the nighttime PBL depth during August in Reno. Further, we expect to gain a better understanding of the impact of mixing volume changes (i.e., PBL height) on air quality and pollution concentrations in Reno. The custom portable sensor design will also be presented. It is expected that these instruments can be used for indoor or outdoor air quality studies, where lightness, small size, and battery operation can be of benefit.

  17. Effects of moderate and heavy endurance exercise on nocturnal HRV.

    Science.gov (United States)

    Hynynen, E; Vesterinen, V; Rusko, H; Nummela, A

    2010-06-01

    This study examined the effects of endurance exercise on nocturnal autonomic modulation. Nocturnal R-R intervals were collected after a rest day, after a moderate endurance exercise and after a marathon run in ten healthy, physically active men. Heart rate variability (HRV) was analyzed as a continuous four-hour period starting 30 min after going to bed for sleep. In relation to average nocturnal heart rate after rest day, increases to 109+/-6% and 130+/-11% of baseline were found after moderate endurance exercise and marathon, respectively. Standard deviation of R-R intervals decreased to 90+/-9% and 64+/-10%, root-mean-square of differences between adjacent R-R intervals to 87+/-10% and 55+/-16%, and high frequency power to 77+/-19% and 34+/-19% of baseline after moderate endurance exercise and marathon, respectively. Also nocturnal low frequency power decreased to 56+/-26% of baseline after the marathon. Changes in nocturnal heart rate and HRV suggest prolonged dose-response effects on autonomic modulation after exercises, which may give useful information on the extent of exercise-induced nocturnal autonomic modulation and disturbance to the homeostasis.

  18. Collaboration in Healthcare Through Boundary Work and Boundary Objects

    DEFF Research Database (Denmark)

    Meier, Ninna

    2015-01-01

    This article contributes to our understanding of how boundary work is practiced in healthcare settings. Previous studies have shown how boundaries are constantly changing, multiple, and co-existing, and can also be relatively stable cognitive and social distinctions between individuals and groups...

  19. An observational study of the evolution of the atmospheric boundary-layer over Cabo Frio, Brazil

    Directory of Open Access Journals (Sweden)

    S. H. Franchito

    2007-08-01

    Full Text Available The effect of coastal upwelling on the evolution of the atmospheric boundary layer (ABL in Cabo Frio (Brazil is investigated. For this purpose, radiosounding data collected in two experiments made during the austral summer (upwelling case and austral winter (no upwelling case are analysed. The results show that during the austral summer, cold waters that crop up near the Cabo Frio coast favour the formation of an atmospheric stable layer, which persists during the upwelling episode. Due to the low SSTs, the descending branch of the sea-breeze circulation is located close to the coast, inhibiting the development of a mixed layer mainly during the day. At night, with the reduction of the land-sea thermal contrast the descending motion is weaker, allowing a vertical mixing. The stable ABL favours the formation of a low level jet, which may also contribute to the development of a nocturnal atmospheric mixed layer. During the austral winter, due to the higher SSTs observed near the coast, the ABL is less stable compared with that in the austral summer. Due to warming, a mixed layer is observed during the day. The observed vertical profiles of the zonal winds show that the easterlies at low levels are stronger in the austral summer, indicating that the upwelling modulates the sea-breeze signal, thus confirming model simulations.

  20. Monitoring nocturnal heart rate with bed sensor.

    Science.gov (United States)

    Migliorini, M; Kortelainen, J M; Pärkkä, J; Tenhunen, M; Himanen, S L; Bianchi, A M

    2014-01-01

    This article is part of the Focus Theme of Methods of Information in Medicine on "Biosignal Interpretation: Advanced Methods for Studying Cardiovascular and Respiratory Systems". The aim of this study is to assess the reliability of the estimated Nocturnal Heart Rate (HR), recorded through a bed sensor, compared with the one obtained from standard electrocardiography (ECG). Twenty-eight sleep deprived patients were recorded for one night each through matrix of piezoelectric sensors, integrated into the mattress, through polysomnography (PSG) simultaneously. The two recording methods have been compared in terms of signal quality and differences in heart beat detection. On average, coverage of 92.7% of the total sleep time was obtained for the bed sensor, testifying the good quality of the recordings. The average beat-to-beat error of the inter-beat intervals was 1.06%. These results suggest a good overall signal quality, however, considering fast heart rates (HR > 100 bpm), performances were worse: in fact, the sensitivity in the heart beat detection was 28.4% while the false positive rate was 3.8% which means that a large amount of fast beats were not detected. The accuracy of the measurements made using the bed sensor has less than 10% of failure rate especially in periods with HR lower than 70 bpm. For fast heart beats the uncertainty increases. This can be explained by the change in morphology of the bed sensor signal in correspondence of a higher HR.

  1. Necrotizing Fasciitis in Paroxysmal Nocturnal Hemoglobinuria

    Directory of Open Access Journals (Sweden)

    Pusem Patir

    2015-01-01

    Full Text Available Paroxysmal nocturnal hemoglobinuria (PNH is a rare, progressive, and life-threatening hematopoietic stem cell disorder characterized by complement-mediated intravascular hemolysis and a prothrombotic state. Patients with PNH might have slightly increased risk of infections due to complement-associated defects subsequent to CD59 deficiency. Here, we report a rare case of a 65-year-old male patient with necrotic ulcers on both legs, where the recognition of pancytopenia and microthrombi led to the diagnosis of PNH based on FLAER (FLuorescent AERolysin flow cytometric analysis. He was subsequently started on eculizumab therapy, with starting and maintenance doses set as per drug labelling. Progression of the patient’s leg ulcers during follow-up, with fulminant tissue destruction, purulent discharge, and necrotic patches, led to a later diagnosis of necrotizing fasciitis due to Pseudomonas aeruginosa and Klebsiella pneumonia infection. Courses of broad-spectrum antibiotics, surgical debridement, and superficial skin grafting were applied with successful effect during ongoing eculizumab therapy. This case highlights the point that it is important to maintain treatment of underlying disorders such as PNH in the presence of life-threatening infections like NF.

  2. Nocturnal enuresis among primary school children

    Directory of Open Access Journals (Sweden)

    Hasan Mohamed Aljefri

    2013-01-01

    Full Text Available To determine the prevalence and personal and family risk factors for nocturnal enuresis (NE among primary school children in Al-Mukalla City, Yemen, we conducted a cross-sectional survey using a self-administered, three-part structured questionnaire involving 832 school children aged 6 - 15 years between 2007 and 2008. We assessed participants′ socio-demographic factors, family characteristics and factors related to the presence of NE. The mean age of the children was 11.5 (±2.7 years. The overall prevalence of NE was 28.6%, with a predominance of girls, and the prevalence decreased with increasing age (P 0.002 and a higher number of siblings (P = 0.01. Our findings reveal a high prevalence of NE among children in Al-Mukalla City, Yemen, with a higher prevalence in girls than in boys compared with the other studies. Sleep pattern, stressful life events, family history of NE, large family size and more children in the household may act as a risk factor for NE.

  3. Seasonal associations with urban light pollution for nocturnally migrating bird populations.

    Science.gov (United States)

    La Sorte, Frank A; Fink, Daniel; Buler, Jeffrey J; Farnsworth, Andrew; Cabrera-Cruz, Sergio A

    2017-11-01

    The spatial extent and intensity of artificial light at night (ALAN) has increased worldwide through the growth of urban environments. There is evidence that nocturnally migrating birds are attracted to ALAN, and there is evidence that nocturnally migrating bird populations are more likely to occur in urban areas during migration, especially in the autumn. Here, we test if urban sources of ALAN are responsible, at least in part, for these observed urban associations. We use weekly estimates of diurnal occurrence and relative abundance for 40 nocturnally migrating bird species that breed in forested environments in North America to assess how associations with distance to urban areas and ALAN are defined across the annual cycle. Migratory bird populations presented stronger than expected associations with shorter distances to urban areas during migration, and stronger than expected association with higher levels of ALAN outside and especially within urban areas during migration. These patterns were more pronounced during autumn migration, especially within urban areas. Outside of the two migration periods, migratory bird populations presented stronger than expected associations with longer distances to urban areas, especially during the nonbreeding season, and weaker than expected associations with the highest levels of ALAN outside and especially within urban areas. These findings suggest that ALAN is associated with higher levels of diurnal abundance along the boundaries and within the interior of urban areas during migration, especially in the autumn when juveniles are undertaking their first migration journey. These findings support the conclusion that urban sources of ALAN can broadly effect migratory behavior, emphasizing the need to better understand the implications of ALAN for migratory bird populations. © 2017 John Wiley & Sons Ltd.

  4. Nocturnal vision and landmark orientation in a tropical halictid bee.

    Science.gov (United States)

    Warrant, Eric J; Kelber, Almut; Gislén, Anna; Greiner, Birgit; Ribi, Willi; Wcislo, William T

    2004-08-10

    Some bees and wasps have evolved nocturnal behavior, presumably to exploit night-flowering plants or avoid predators. Like their day-active relatives, they have apposition compound eyes, a design usually found in diurnal insects. The insensitive optics of apposition eyes are not well suited for nocturnal vision. How well then do nocturnal bees and wasps see? What optical and neural adaptations have they evolved for nocturnal vision? We studied female tropical nocturnal sweat bees (Megalopta genalis) and discovered that they are able to learn landmarks around their nest entrance prior to nocturnal foraging trips and to use them to locate the nest upon return. The morphology and optics of the eye, and the physiological properties of the photoreceptors, have evolved to give Megalopta's eyes almost 30 times greater sensitivity to light than the eyes of diurnal worker honeybees, but this alone does not explain their nocturnal visual behavior. This implies that sensitivity is improved by a strategy of photon summation in time and in space, the latter of which requires the presence of specialized cells that laterally connect ommatidia into groups. First-order interneurons, with significantly wider lateral branching than those found in diurnal bees, have been identified in the first optic ganglion (the lamina ganglionaris) of Megalopta's optic lobe. We believe that these cells have the potential to mediate spatial summation. Despite the scarcity of photons, Megalopta is able to visually orient to landmarks at night in a dark forest understory, an ability permitted by unusually sensitive apposition eyes and neural photon summation.

  5. Nocturnal surface ozone enhancement over Portugal during winter: Influence of different atmospheric conditions

    KAUST Repository

    Kulkarni, Pavan S.

    2016-09-24

    Four distinct nocturnal surface ozone (NSO) enhancement events were observed, with NSO concentration exceeding 80μg/m3, at multiple ozone (O3) monitoring stations (32 sites) in January, November and December between year 2000–2010, in Portugal. The reasonable explanation for the observed bimodal pattern of surface ozone with enhanced NSO concentration during nighttime has to be transport processes, as the surface ozone production ceases at nighttime. Simultaneous measurements of O3 at multiple stations during the study period in Portugal suggest that horizontal advection alone cannot explain the observed NSO enhancement. Thus, detailed analysis of the atmospheric conditions, simulated with the Weather Research and Forecasting (WRF) model, were performed to evaluate the atmospheric mechanisms responsible for NSO enhancement in the region. Simulations revealed that each event occurred as a result of one or the combination of different atmospheric processes such as, passage of a cold front followed by a subsidence zone; passage of a moving surface trough, with associated strong horizontal wind speed and vertical shear; combination of vertical and horizontal transport at the synoptic scale; formation of a low level jet with associated vertical mixing below the jet stream. The study confirmed that large-scale flow pattern resulting in enhanced vertical mixing in the nocturnal boundary layer, plays a key role in the NSO enhancement events, which frequently occur over Portugal during winter months. © 2016 Elsevier Ltd

  6. Nocturnal surface ozone enhancement over Portugal during winter: Influence of different atmospheric conditions

    KAUST Repository

    Kulkarni, Pavan S.; Dasari, Hari Prasad; Sharma, Ashish; Bortoli, D.; Salgado, Rui; Silva, A.M.

    2016-01-01

    Four distinct nocturnal surface ozone (NSO) enhancement events were observed, with NSO concentration exceeding 80μg/m3, at multiple ozone (O3) monitoring stations (32 sites) in January, November and December between year 2000–2010, in Portugal. The reasonable explanation for the observed bimodal pattern of surface ozone with enhanced NSO concentration during nighttime has to be transport processes, as the surface ozone production ceases at nighttime. Simultaneous measurements of O3 at multiple stations during the study period in Portugal suggest that horizontal advection alone cannot explain the observed NSO enhancement. Thus, detailed analysis of the atmospheric conditions, simulated with the Weather Research and Forecasting (WRF) model, were performed to evaluate the atmospheric mechanisms responsible for NSO enhancement in the region. Simulations revealed that each event occurred as a result of one or the combination of different atmospheric processes such as, passage of a cold front followed by a subsidence zone; passage of a moving surface trough, with associated strong horizontal wind speed and vertical shear; combination of vertical and horizontal transport at the synoptic scale; formation of a low level jet with associated vertical mixing below the jet stream. The study confirmed that large-scale flow pattern resulting in enhanced vertical mixing in the nocturnal boundary layer, plays a key role in the NSO enhancement events, which frequently occur over Portugal during winter months. © 2016 Elsevier Ltd

  7. Observational assessment of the role of nocturnal residual-layer chemistry in determining daytime surface particulate nitrate concentrations

    Directory of Open Access Journals (Sweden)

    G. Prabhakar

    2017-12-01

    Full Text Available This study discusses an analysis of combined airborne and ground observations of particulate nitrate (NO3−(p concentrations made during the wintertime DISCOVER-AQ (Deriving Information on Surface Conditions from COlumn and VERtically resolved observations relevant to Air Quality study at one of the most polluted cities in the United States – Fresno, CA – in the San Joaquin Valley (SJV and focuses on developing an understanding of the various processes that impact surface nitrate concentrations during pollution events. The results provide an explicit case-study illustration of how nighttime chemistry can influence daytime surface-level NO3−(p concentrations, complementing previous studies in the SJV. The observations exemplify the critical role that nocturnal chemical production of NO3−(p aloft in the residual layer (RL can play in determining daytime surface-level NO3−(p concentrations. Further, they indicate that nocturnal production of NO3−(p in the RL, along with daytime photochemical production, can contribute substantially to the buildup and sustaining of severe pollution episodes. The exceptionally shallow nocturnal boundary layer (NBL heights characteristic of wintertime pollution events in the SJV intensify the importance of nocturnal production aloft in the residual layer to daytime surface concentrations. The observations also demonstrate that dynamics within the RL can influence the early-morning vertical distribution of NO3−(p, despite low wintertime wind speeds. This overnight reshaping of the vertical distribution above the city plays an important role in determining the net impact of nocturnal chemical production on local and regional surface-level NO3−(p concentrations. Entrainment of clean free-tropospheric (FT air into the boundary layer in the afternoon is identified as an important process that reduces surface-level NO3−(p and limits buildup during pollution episodes. The influence of dry deposition of HNO

  8. Diagnosing the pathophysiologic mechanisms of nocturnal polyuria.

    Science.gov (United States)

    Goessaert, An-Sofie; Krott, Louise; Hoebeke, Piet; Vande Walle, Johan; Everaert, Karel

    2015-02-01

    Diagnosis of nocturnal polyuria (NP) is based on a bladder diary. Addition of a renal function profile (RFP) for analysis of concentrating and solute-conserving capacity allows differentiation of NP pathophysiology and could facilitate individualized treatment. To map circadian rhythms of water and solute diuresis by comparing participants with and without NP. This prospective observational study was carried out in Ghent University Hospital between 2011 and 2013. Participants with and without NP completed a 72-h bladder dairy. RFP, free water clearance (FWC), and creatinine, solute, sodium, and urea clearance were measured for all participants. The study participants were divided into those with (n=77) and those without (n=35) NP. The mean age was 57 yr (SD 16 yr) and 41% of the participants were female. Compared to participants without NP, the NP group exhibited a higher diuresis rate throughout the night (p=0.015); higher FWC (p=0.013) and lower osmolality (p=0.030) at the start of the night; and persistently higher sodium clearance during the night (p<0.001). The pathophysiologic mechanism of NP was identified as water diuresis alone in 22%, sodium diuresis alone in 19%, and a combination of water and sodium diuresis in 47% of the NP group. RFP measurement in first-line NP screening to discriminate between water and solute diuresis as pathophysiologic mechanisms complements the bladder diary and could facilitate optimal individualized treatment of patients with NP. We evaluated eight urine samples collected over 24h to detect the underlying problem in NP. We found that NP can be attributed to water or sodium diuresis or a combination of both. This urinalysis can be used to adapt treatment according to the underlying mechanism in patients with bothersome consequences of NP, such as nocturia and urinary incontinence. Copyright © 2014 European Association of Urology. Published by Elsevier B.V. All rights reserved.

  9. Does menopause influence nocturnal awakening with headache?

    Science.gov (United States)

    Lucchesi, L M; Hachul, H; Yagihara, F; Santos-Silva, R; Tufik, S; Bittencourt, L

    2013-06-01

    The aim of the present study was to assess whether menopausal status influences the occurrence of nocturnal awakening with headache (NAH) in the female population of Sao Paulo, Brazil. We also examined the relationship of this complaint to sociodemographic determinants, hot flushes, sleep quality and parameters, anxiety and depressive symptoms, somnolence and fatigue according to menopausal status. The female population of the Sao Paulo Epidemiologic Sleep Study (EPISONO) (n = 576) was divided according to menopausal status (pre-, peri-, early and late menopause) based on questionnaires and hormonal blood measures. The complaint of waking up because of a headache at least once a week was assessed by the UNIFESP Sleep questionnaire. Additionally, hot flushes, sleep complaints, anxiety and depressive symptoms, somnolence and fatigue were assessed by specific questionnaires. A full-night polysomnography assessed sleep parameters. The prevalence of NAH in women in the Sao Paulo population was 13.3%. Perimenopause was associated with a higher risk of having NAH (odds ratio 13.9; 95% confidence interval 4.3-45.2). More complaints of NAH were observed in obese women. All the groups with NAH showed more hot flushes, worse subjective sleep quality, more complaints of insomnia, anxiety symptoms and fatigue. We observed a constellation of symptoms in women according to menopausal status and NAH that included hot flushes, sleep complaints, more anxiety symptoms and fatigue. Moreover, some of these symptoms were more frequent in perimenopausal women with NAH. Therefore, we concluded that menopausal status influences NAH and the women in perimenopause presented a high risk of having this complaint.

  10. Global effects of moon phase on nocturnal acoustic scattering layers

    KAUST Repository

    Prihartato, PK

    2016-01-18

    © Inter-Research 2016. The impact of moon phase on the global nocturnal vertical distribution of acoustic scattering layers (SLs) in the upper 200 m was studied during the Malaspina expedition that circumnavigated the world. We assessed the nocturnal weighted mean depths and the vertical extension of the SL (the range between the upper 25th percentile and lower 75th percentile of the backscatter) and used a generalized additive model to reveal the relationship between the nocturnal vertical distribution of the SL and moon phase, as well as other environmental factors. Moon phase significantly affected the SL distribution on a global scale, in contrast to other factors such as dissolved oxygen, temperature and fluorescence, which each correlated with nocturnal SL distribution during the large geographic coverage. Full moon caused a deepening effect on the nocturnal SL. Contrary to expectations, the shallowest distribution was not observed during the darkest nights (new moon) and there was no difference in vertical distribution between new moon and intermediate moon phases. We conclude that the trend of deepening SL during approximately full moon (bright nights) is a global phenomenon related to anti-predator behavior.

  11. Global effects of moon phase on nocturnal acoustic scattering layers

    KAUST Repository

    Prihartato, Perdana; Irigoien, Xabier; Genton, Marc G.; Kaartvedt, Stein

    2016-01-01

    © Inter-Research 2016. The impact of moon phase on the global nocturnal vertical distribution of acoustic scattering layers (SLs) in the upper 200 m was studied during the Malaspina expedition that circumnavigated the world. We assessed the nocturnal weighted mean depths and the vertical extension of the SL (the range between the upper 25th percentile and lower 75th percentile of the backscatter) and used a generalized additive model to reveal the relationship between the nocturnal vertical distribution of the SL and moon phase, as well as other environmental factors. Moon phase significantly affected the SL distribution on a global scale, in contrast to other factors such as dissolved oxygen, temperature and fluorescence, which each correlated with nocturnal SL distribution during the large geographic coverage. Full moon caused a deepening effect on the nocturnal SL. Contrary to expectations, the shallowest distribution was not observed during the darkest nights (new moon) and there was no difference in vertical distribution between new moon and intermediate moon phases. We conclude that the trend of deepening SL during approximately full moon (bright nights) is a global phenomenon related to anti-predator behavior.

  12. Nocturnal asthma in school children of south punjab, pakistan

    International Nuclear Information System (INIS)

    Mustafa, G.; Khan, P.A.; Iqbal, I.

    2008-01-01

    At the present time, the epidemiology of the childhood asthma is of considerable interest. There is an understandable concern that changes in the geographical area, lifestyle, and environment. This study was conducted to find the prevalence of nocturnal asthma, in school children of south Punjab, Pakistan. It was a cross sectional, questionnaire based, descriptive survey of the children aged 3-18 years, in randomly selected primary and secondary schools, from October 2002 to March 2003. The data was analysed with Statistical Analysis System (SAS). Of 6120 questionnaire sent to the parents/guardians, we received 3180 back (52%). Of the 3180 respondents, 1767 (56%) were for boys and 1413 (44%) were for girls. The median age was 8.25 years. Around 71% of children were between 4 to 11 years of age. The parents reported nocturnal asthma in 177 (6%) of their children with an equal prevalence in boys and girls, i.e., (3% each, rounded off to nearest whole number). Of these 177 children with nocturnal asthma, 99 (56%) were boys and 78 (44%) were girls. Of the 1767 boys and 1413 girls, the nocturnal asthma reported by parents was 6% each (99 and 78 respectively). The nocturnal asthma was not reported in 14-18 years age group of females. The asthma is taken as a stigma in our society and as such is not reported or disclosed rather denied. An extensive educational media campaign is required for awareness of the masses. (author)

  13. Differences in ocular parameters between diurnal and nocturnal raptors.

    Science.gov (United States)

    Beckwith-Cohen, Billie; Horowitz, Igal; Bdolah-Abram, Tali; Lublin, Avishai; Ofri, Ron

    2015-01-01

    To establish and compare normal ocular parameters between and within diurnal and nocturnal raptor groups. Eighty-eight ophthalmically normal raptors of six nocturnal and 11 diurnal species were studied. Tear production was measured using Schirmer tear test (STT) and phenol red thread test (PRTT), and applanation tonometry was conducted. Ultrasonographic measurements of axial length (AL), mediolateral axis (ML), vitreous body (VB), and pecten length (PL) were recorded, and conjunctival cultures were obtained. A weak correlation (R = 0.312, P = 0.006) was found between PRTT and STT. Tear production was significantly lower in nocturnal species (P raptors were positive for mycology or bacteriology, either on culture or PCR. The most common infectious agent isolated was Staphylococcus spp. Phenol red thread test and STT are both valid methods to measure tear production; however, a separate baseline must be determined for each species using these methods, as the results of one method cannot be extrapolated to the other. Due to significant differences observed within diurnal and nocturnal species, it appears that a more intricate division should be used when comparing these parameters for raptors, and the classification of diurnal or nocturnal holds little significance in the baseline of these data. © 2013 American College of Veterinary Ophthalmologists.

  14. Eye shape and the nocturnal bottleneck of mammals.

    Science.gov (United States)

    Hall, Margaret I; Kamilar, Jason M; Kirk, E Christopher

    2012-12-22

    Most vertebrate groups exhibit eye shapes that vary predictably with activity pattern. Nocturnal vertebrates typically have large corneas relative to eye size as an adaptation for increased visual sensitivity. Conversely, diurnal vertebrates generally demonstrate smaller corneas relative to eye size as an adaptation for increased visual acuity. By contrast, several studies have concluded that many mammals exhibit typical nocturnal eye shapes, regardless of activity pattern. However, a recent study has argued that new statistical methods allow eye shape to accurately predict activity patterns of mammals, including cathemeral species (animals that are equally likely to be awake and active at any time of day or night). Here, we conduct a detailed analysis of eye shape and activity pattern in mammals, using a broad comparative sample of 266 species. We find that the eye shapes of cathemeral mammals completely overlap with nocturnal and diurnal species. Additionally, most diurnal and cathemeral mammals have eye shapes that are most similar to those of nocturnal birds and lizards. The only mammalian clade that diverges from this pattern is anthropoids, which have convergently evolved eye shapes similar to those of diurnal birds and lizards. Our results provide additional evidence for a nocturnal 'bottleneck' in the early evolution of crown mammals.

  15. New-particle formation events in a continental boundary layer: first results from the SATURN experiment

    Directory of Open Access Journals (Sweden)

    F. Stratmann

    2003-01-01

    Full Text Available During the SATURN experiment, which took place from 27 May to 14 June 2002, new particle formation in the continental boundary layer was investigated. Simultaneous ground-based and tethered-balloon-borne measurements were performed, including meteorological parameters, particle number concentrations and size distributions, gaseous precursor concentrations and SODAR and LIDAR observations. Newly formed particles were observed inside the residual layer, before the break-up process of the nocturnal inversion, and inside the mixing layer throughout the break-up of the nocturnal inversion and during the evolution of the planetary boundary layer.

  16. Eight-Year Experience with Nocturnal, Every-Other-Day, Online Haemodiafiltration.

    Science.gov (United States)

    Maduell, Francisco; Ojeda, Raquel; Arias-Guillen, Marta; Rossi, Florencia; Fontseré, Néstor; Vera, Manel; Rico, Nayra; Gonzalez, Leonardo Nicolás; Piñeiro, Gastón; Jiménez-Hernández, Mario; Rodas, Lida; Bedini, José Luis

    2016-01-01

    New haemodialysis therapeutic regimens are required to improve patient survival. Longer and more frequent dialysis sessions have produced excellent survival and clinical advantages, while online haemodiafiltration (OL-HDF) provides the most efficient form of dialysis treatment. In this single-centre observational study, 57 patients on 4-5-hour thrice-weekly OL-HDF were switched to nocturnal every-other-day OL-HDF. Inclusion criteria consisted of stable patients with good prospects for improved occupational, psychological and social rehabilitation. The aim of this study was to report our 8-year experience with this schedule and to evaluate analytical and clinical outcomes. Nocturnal, every-other-day OL-HDF was well tolerated and 56% of patients were working. The convective volume increased from 26.7 ± 2 litres at baseline to 46.6 ± 6.5 litres at 24 months (p every-other-day OL-HDF could be an excellent therapeutic alternative since it is well tolerated and leads to clinical and social-occupational rehabilitation with satisfactory morbidity and mortality. These encouraging results strengthen us to continue and invite other clinicians to join this initiative. © 2016 S. Karger AG, Basel.

  17. Nocturnal, every-other-day, online haemodiafiltration: an effective therapeutic alternative.

    Science.gov (United States)

    Maduell, Francisco; Arias, Marta; Durán, Carlos E; Vera, Manel; Fontseré, Néstor; Azqueta, Manel; Rico, Nayra; Pérez, Nuria; Sentis, Alexis; Elena, Montserrat; Rodriguez, Néstor; Arcal, Carola; Bergadá, Eduardo; Cases, Aleix; Bedini, Jose Luis; Campistol, Josep M

    2012-04-01

    Longer and more frequent dialysis sessions have demonstrated excellent survival and clinical advantages, while online haemodiafiltration (OL-HDF) provides the most efficient form of dialysis treatment. The aim of this study was to evaluate the beneficial effects of a longer (nocturnal) and more frequent (every-other-day) dialysis schedule with OL-HDF at the same or the highest convective volume. This prospective, in-centre crossover study was carried out in 26 patients, 18 males and 8 females, 49.2±14 years old, on 4-5 h thrice-weekly post-dilution OL-HDF, switched to nocturnal every-other-day OL-HDF. Patient inclusion criteria consisted of stable patients with good vascular access and with good prospects for improved occupational, psychological and social rehabilitation. Patients were randomly assigned into two groups: Group A received the same convective volume as previously for 6 months followed by a higher convective volume for a further 6 months, while Group B received the same schedule in reverse order. Nocturnal every-other-day OL-HDF was well tolerated and 56% of patients who were working during the baseline period continued to work throughout the study with practically no absenteeism. The convective volume was 26.7±2 L at baseline, 27.5±2 with the unchanged volume and 42.9±4 L with the higher volume. eKt/V increased from 1.75±0.4 to 3.37±0.9. Bicarbonate, blood urea nitrogen (BUN) and creatinine values decreased, while phosphate levels fell markedly with a 90% reduction in phosphate binders. Blood pressure and left ventricular hypertrophy (LVH) improved and the use of anti-hypertensive drugs decreased. In both groups, BUN, creatinine and β2-microglobulin reduction ratios improved. Different removal patterns were observed for myoglobin, prolactin and α1-acid glycoprotein. Nocturnal every-other-day OL-HDF could be an excellent therapeutic alternative since good tolerance and occupational rehabilitation, marked improvement in dialysis dose

  18. Nocturnal Hypertension: Neglected Issue in Comprehensive Hypertension Management

    Directory of Open Access Journals (Sweden)

    Andi Kristanto

    2016-09-01

    Full Text Available The body circardian rhythm affects blood pressure variability at day and night, therefore blood pressure at day and night might be different. Nocturnal hypertension is defined as increase of blood pressure >120/70mmHg at night, which is caused by disturbed circadian rhythm, and associated with higher cardiovascular and cerebrovascular events also mortality in hypertensive patients. Nocturnal hypertension and declining blood pressure pattern, can only be detected by continuous examination for 24 hours, also known as ambulatory blood pressure measurement (ABPM. Chronotherapy, has become a strategy for managing the hypertensive nocturnal patients, by taking hypertensive medication at night to obtain normal blood pressure decrease in accordance with the normal circadian rhythm and, improving blood pressure control.

  19. On the impact of atmospheric thermal stability on the characteristics of nocturnal downslope flows

    Science.gov (United States)

    Ye, Z. J.; Garratt, J. R.; Segal, M.; Pielke, R. A.

    1990-04-01

    The impacts of background (or ambient) and local atmospheric thermal stabilities, and slope steepness, on nighttime thermally induced downslope flow in meso-β domains (i.e., 20 200 km horizontal extent) have been investigated using analytical and numerical model approaches. Good agreement between the analytical and numerical evaluations was found. It was concluded that: (i) as anticipated, the intensity of the downslope flow increases with increased slope steepness, although the depth of the downslope flow was found to be insensitive to slope steepness in the studied situations; (ii) the intensity of the downslope flow is generally independent of background atmospheric thermal stability; (iii) for given integrated nighttime cooling across the nocturnal boundary layer (NBL), Q s the local atmospheric thermal stability exerts a strong influence on downslope flow behavior: the downslope flow intensity increases when local atmospheric thermal stability increases; and (iv) the downslope flow intensity is proportional to Q s 1/2.

  20. Unpredictably Stable

    DEFF Research Database (Denmark)

    Failla, Virgilio; Melillo, Francesca; Reichstein, Toke

    2014-01-01

    Is entrepreneurship a more stable career choice for high employment turnover individuals? We find that a transition to entrepreneurship induces a shift towards stayer behavior and identify job matching, job satisfaction and lock-in effects as main drivers. These findings have major implications...

  1. Micro-arousals during nocturnal sleep.

    Science.gov (United States)

    Halász, P; Kundra, O; Rajna, P; Pál, I; Vargha, M

    1979-01-01

    In 8 young adult human subjects EEG- and polygraphic characteristics of transient shifts towards arousal (micro-arousal, MA) have been studied during sleep under five different experimental conditions in 40 night sessions. Out of the five applied experimental situations, two (psychostimulant application and sensory stimulation) resulted in a shift of the balance between the systems of sleep and arousal towards an increased activity of the arousal system, while an other condition (rebound following partial sleep deprivation) led to an opposite change to a rise in "sleep pressure". An inverse correlation has been found between the frequency of MA and the depth of sleep, a finding consistently observed in every subject and in every experimental situation. During the process of sleep periodic changes in the dispersity of MA could be seen; the number of MA-s decreased and increased according to the descending and ascending slope of the sleep cycles. During the ascending slope of cycles there was a coupling between the occurence of MA-s and the changes of phases. Increases in the level of activation and in sleep pressure did not influence the occurrence of MA-s. Increasing the tone of the arousal system in chemical way, or by means of enhancing the phasic sensory input resulted in a reduction of the difference between the number of MA on the descending and ascending slopes of cycles. During the phases of sleep, the spontaneous occurrence of MA-s went parallel with the possibility to evoke MA-s by sensory stimuli. These data show that MA is a regular phenomenon of nocturnal sleep; MA manifests itself as a result of phasic functioning of the reticular arousal system and plays a role in the organization of those periods of the sleep cycle, which tend toward arousal. It is suggested that MA-phenomenon is considered a standard measure of sleep and that it could represent an indicator of the function of the arousal system controlled by external or internal mechanisms during

  2. Circadian rhythm of temperature selection in a nocturnal lizard.

    Science.gov (United States)

    Refinetti, R; Susalka, S J

    1997-08-01

    We recorded body temperature and locomotor activity of Tokay geckos (Gekko gecko) with free access to a heat source under a 14:10 light-dark cycle and in constant darkness. Under the light-dark cycle, the lizards selected higher temperatures during the light phase, when locomotor activity was less intense. Rhythmicity in temperature selection was transiently disrupted but later resumed when the animals were placed in constant darkness. These results demonstrate the existence of a circadian rhythm of temperature selection in nocturnal ectotherms and extend previous findings of a temporal mismatch between the rhythms of locomotor activity and temperature selection in nocturnal rodents.

  3. Emerging boundaries

    DEFF Research Database (Denmark)

    Løvschal, Mette

    2014-01-01

    of temporal and material variables have been applied as a means of exploring the processes leading to their socioconceptual anchorage. The outcome of this analysis is a series of interrelated, generative boundary principles, including boundaries as markers, articulations, process-related devices, and fixation...

  4. Changing Boundaries

    DEFF Research Database (Denmark)

    Brodkin, Evelyn; Larsen, Flemming

    2013-01-01

    project that is altering the boundary between the democratic welfare state and the market economy. We see workfare policies as boundary-changing with potentially profound implications both for individuals disadvantaged by market arrangements and for societies seeking to grapple with the increasing...

  5. Stable particles

    International Nuclear Information System (INIS)

    Samios, N.P.

    1993-01-01

    I have been asked to review the subject of stable particles, essentially the particles that eventually comprised the meson and baryon octets. with a few more additions -- with an emphasis on the contributions made by experiments utilizing the bubble chamber technique. In this activity, much work had been done by the photographic emulsion technique and cloud chambers-exposed to cosmic rays as well as accelerator based beams. In fact, many if not most of the stable particles were found by these latter two techniques, however, the forte of the bubble chamber (coupled with the newer and more powerful accelerators) was to verify, and reinforce with large statistics, the existence of these states, to find some of the more difficult ones, mainly neutrals and further to elucidate their properties, i.e., spin, parity, lifetimes, decay parameters, etc

  6. Negotiating boundaries

    DEFF Research Database (Denmark)

    Aarhus, Rikke; Ballegaard, Stinne Aaløkke

    2010-01-01

    to maintain the order of the home when managing disease and adopting new healthcare technology. In our analysis we relate this boundary work to two continuums of visibility-invisibility and integration-segmentation in disease management. We explore five factors that affect the boundary work: objects......, activities, places, character of disease, and collaboration. Furthermore, the processes are explored of how boundary objects move between social worlds pushing and shaping boundaries. From this we discuss design implications for future healthcare technologies for the home.......To move treatment successfully from the hospital to that of technology assisted self-care at home, it is vital in the design of such technologies to understand the setting in which the health IT should be used. Based on qualitative studies we find that people engage in elaborate boundary work...

  7. A Climatology of Nocturnal Low-Level Jets at Cabauw

    NARCIS (Netherlands)

    Baas, P.; Bosveld, F.C.; Baltink, H.K.; Holtslag, A.A.M.

    2009-01-01

    A climatology of nocturnal low-level jets (LLJs) is presented for the topographically flat measurement site at Cabauw, the Netherlands. LLJ characteristics are derived from a 7-yr half-hourly database of wind speed profiles, obtained from the 200-m mast and a wind profiler. Many LLJs at Cabauw

  8. Male broiler performance and nocturnal feeding under constant 8-h ...

    African Journals Online (AJOL)

    ... however, they still consumed more feed in the 8-h dark period than birds that had always been given 16 h illumination. Cobb and Ross genotypes responded similarly to all lighting treatments. Keywords: Photoperiod, broiler growth, nocturnal feeding. South African Journal of Animal Science Vol. 38 (3) 2008: pp. 159-165 ...

  9. Does petroleum development affect burrowing owl nocturnal space-use?

    Energy Technology Data Exchange (ETDEWEB)

    Scobie, Corey; Wellicome, Troy; Bayne, Erin [Department of Biological Sciences, University of Alberta (Canada)], email: cscobie@ualberta.ca, email: tiw@ualberta.ca, email: bayne@ualberta.ca

    2011-07-01

    Decline all over Canada in the population of burrowing owls, a federally listed endangered species, has raised concerns about the possible influence of petroleum infrastructure development on owl nocturnal space-use while foraging. Roads, wells, pipelines and sound-producing facilities related to petroleum development change the landscape and can influence the owls' mortality risk. For 3 years, 27 breeding adult male burrowing owls with nests close to different petroleum infrastructures were captured and fitted with a miniature GPS datalogger in order to track their nocturnal foraging. Data from these GPS devices were fed into a geographical information system and showed that pipelines and wells did not alter the foraging habits of the owls. Dirt and gravel roads, with little traffic, were preferentially selected by the owls, conceivably because of higher owl mortality risk along paved roads. Sound-producing facilities did not change owls' foraging behaviour, implying that sound may not affect their nocturnal space-use. Traffic data and sound power measurements will be used in further studies in an effort to better understand burrowing owls' nocturnal foraging habits.

  10. Innovative Visualizations Shed Light on Avian Nocturnal Migration

    NARCIS (Netherlands)

    Shamoun-Baranes, J.; Farnsworth, A.; Aelterman, B.; Alves, J.A.; Azijn, K.; Bernstein, G.; Branco, S.; Desmet, P.; Dokter, A.M.; Horton, K.; Kelling, S.; Kelly, J.F.; Leijnse, H.; Rong, J.; Sheldon, D.; Van den Broeck, W.; Van Den Meersche, J.K.; Van Doren, B.M.; van Gasteren, H.

    2016-01-01

    Globally, billions of flying animals undergo seasonal migrations, many of which occur at night. The temporal and spatial scales at which migrations occur and our inability to directly observe these nocturnal movements makes monitoring and characterizing this critical period in migratory animals’

  11. Eculizumab in Pregnant Patients with Paroxysmal Nocturnal Hemoglobinuria

    NARCIS (Netherlands)

    Kelly, R.J.; Hochsmann, B.; Szer, J.; Kulasekararaj, A.; Guibert, S. de; Roth, A.; Weitz, I.C.; Armstrong, E.; Risitano, A.M.; Patriquin, C.J.; Terriou, L.; Muus, P.; Hill, A.; Turner, M.P.; Schrezenmeier, H.; Peffault de Latour, R.

    2015-01-01

    BACKGROUND: Eculizumab, a humanized monoclonal antibody against complement protein C5 that inhibits terminal complement activation, has been shown to prevent complications of paroxysmal nocturnal hemoglobinuria (PNH) and improve quality of life and overall survival, but data on the use of eculizumab

  12. Nocturnal sleep problems among university students from 26 countries.

    Science.gov (United States)

    Peltzer, Karl; Pengpid, Supa

    2015-05-01

    The aim of this study is to estimate the prevalence of nocturnal sleeping problems and its associated factors among university students in mainly low- and middle-income countries. A cross-sectional survey was conducted with 20,222 undergraduate university students (mean age, 20.8; SD = 2.8) from 27 universities in 26 countries across Asia, Africa and the Americas. Overall, 10.4% reported severe or extreme nocturnal sleeping problems (male, 10.2%; female, 10.5%) in the past month. Noctural sleeping problems differed by country, from 32.9% in Indonesia to 3.0 % in Thailand among Asian countries, from 13.7% in Mauritius to 7.5% in South Africa, and from 11.8% in Jamaica to 6.1% in Columbia in the Americas. In multivariate logistic regression analysis, coming from a poor family background, staying off campus (on their own or with parents or guardians), stress (history of child sexual abuse), poor mental health (depression and PTSD symptoms), health risk behaviour (tobacco use, heavy internet use, gambling, skipping breakfast and having sustained an injury), lack of social support and poor academic performance were associated with nocturnal sleeping problems. A significant prevalence of past-month nocturnal sleeping problems was found. Potential factors associated with the risk of reporting sleeping complaints were identified, which may assist in prevention strategies to promote a better quality of sleep.

  13. Treatment Options for Primary Nocturnal Enuresis by Parents in a ...

    African Journals Online (AJOL)

    femi oloka

    common treatment option was waking up child at intervals during the night to void by 103 (45.2 ... patient/family education, simple behavioral ... nocturnal enuresis were employing in managing ..... Dental and Medical Sciences 2014;13:41 – 4.

  14. Working for Food Shifts Nocturnal Mouse Activity into the Day

    NARCIS (Netherlands)

    Hut, Roelof A.; Pilorz, Violetta; Boerema, Ate S.; Strijkstra, Arjen M.; Daan, Serge; Yamazaki, Shin

    2011-01-01

    Nocturnal rodents show diurnal food anticipatory activity when food access is restricted to a few hours in daytime. Timed food access also results in reduced food intake, but the role of food intake in circadian organization per se has not been described. By simulating natural food shortage in mice

  15. Nocturnal motor activity in fibromyalgia patients with poor sleep quality.

    Science.gov (United States)

    Hyyppä, M T; Kronholm, E

    1995-01-01

    Nocturnal motor activity was examined in long-term rehabilitation patients complaining of poor sleep and having fibromyalgia syndrome (N = 24) or other musculoskeletal disorders (N = 60) and compared with that in 91 healthy controls drawn from a random community sample. Self-reports on sleep complaints and habits were collected. The frequency of nocturnal body movements, the "apnoea" index and ratio of "quiet sleep" to total time in bed were measured using the Static Charge Sensitive Bed (SCSB) (BioMatt). As a group, patients with fibromyalgia syndrome did not differ from patients with other musculoskeletal disorders or from healthy controls in their nocturnal motor activity. The "apnoea" index was a little higher in the fibromyalgia group than in the healthy control group but did not differ from that of the group of other musculoskeletal patients. Further multivariate analyses adjusted for age, BMI, medication and "apnoea" index did not support the assumption that an increased nocturnal motor activity characterizes patients with fibromyalgia syndrome.

  16. Density effects on turbulent boundary layer structure: From the atmosphere to hypersonic flow

    Science.gov (United States)

    Williams, Owen J. H.

    This dissertation examines the effects of density gradients on turbulent boundary layer statistics and structure using Particle Image Velocimetry (PIV). Two distinct cases were examined: the thermally stable atmospheric surface layer characteristic of nocturnal or polar conditions, and the hypersonic bounder layer characteristic of high speed aircraft and reentering spacecraft. Previous experimental studies examining the effects of stability on turbulent boundary layers identified two regimes, weak and strong stability, separated by a critical bulk stratification with a collapse of near-wall turbulence thought to be intrinsic to the strongly stable regime. To examine the characteristics of these two regimes, PIV measurements were obtained in conjunction with the mean temperature profile in a low Reynolds number facility over smooth and rough surfaces. The turbulent stresses were found to scale with the wall shear stress in the weakly stable regime prior relaminarization at a critical stratification. Changes in profile shape were shown to correlate with the local stratification profile, and as a result, the collapse of near-wall turbulence is not intrinsic to the strongly stable regime. The critical bulk stratification was found to be sensitive to surface roughness and potentially Reynolds number, and not constant as previously thought. Further investigations examined turbulent boundary layer structure and changes to the motions that contribute to turbulent production. To study the characteristics of a hypersonic turbulent boundary layer at Mach 8, significant improvements were required to the implementation and error characterization of PIV. Limited resolution or dynamic range effects were minimized and the effects of high shear on cross-correlation routines were examined. Significantly, an examination of particle dynamics, subject to fluid inertia, compressibility and non-continuum effects, revealed that particle frequency responses to turbulence can be up to an

  17. Sleep Apnea and Nocturnal Cardiac Arrhythmia: A Populational Study

    Directory of Open Access Journals (Sweden)

    Fatima Dumas Cintra

    2014-11-01

    Full Text Available Background: The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea. Objective: To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample. Methods: Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart® system. Results: A total of 767 participants (461 men with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001. After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia. Conclusion: Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.

  18. Stable isotopes

    International Nuclear Information System (INIS)

    Brazier, J.L.; Guinamant, J.L.

    1995-01-01

    According to the progress which has been realised in the technology of separating and measuring isotopes, the stable isotopes are used as preferable 'labelling elements' for big number of applications. The isotopic composition of natural products shows significant variations as a result of different reasons like the climate, the seasons, or their geographic origins. So, it was proved that the same product has a different isotopic composition of alimentary and agriculture products. It is also important in detecting the pharmacological and medical chemicals. This review article deals with the technology, like chromatography and spectrophotometry, adapted to this aim, and some important applications. 17 refs. 6 figs

  19. Stable Tetraquarks

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, Chris [Fermilab

    2018-04-13

    For very heavy quarks, relations derived from heavy-quark symmetry imply novel narrow doubly heavy tetraquark states containing two heavy quarks and two light antiquarks. We predict that double-beauty states will be stable against strong decays, whereas the double-charm states and mixed beauty+charm states will dissociate into pairs of heavy-light mesons. Observing a new double-beauty state through its weak decays would establish the existence of tetraquarks and illuminate the role of heavy color-antitriplet diquarks as hadron constituents.

  20. Desmopressin (melt) therapy in children with monosymptomatic nocturnal enuresis and nocturnal polyuria results in improved neuropsychological functioning and sleep.

    Science.gov (United States)

    Van Herzeele, Charlotte; Dhondt, Karlien; Roels, Sanne P; Raes, Ann; Hoebeke, Piet; Groen, Luitzen-Albert; Vande Walle, Johan

    2016-09-01

    There is a high comorbidity between nocturnal enuresis, sleep disorders and psychological problems. The aim of this study was to investigate whether a decrease in nocturnal diuresis volume not only improves enuresis but also ameliorates disrupted sleep and (neuro)psychological dysfunction, the major comorbidities of this disorder. In this open-label, prospective phase IV study, 30 children with monosymptomatic nocturnal enuresis (MNE) underwent standardized video-polysomnographic testing and multi-informant (neuro)psychological testing at baseline and 6 months after the start of desmopressin treatment in the University Hospital Ghent, Belgium. Primary endpoints were the effect on sleep and (neuro)psychological functioning. The secondary endpoint was the change in the first undisturbed sleep period or the time to the first void. Thirty children aged between 6 and 16 (mean 10.43, standard deviation 3.08) years completed the study. The results demonstrated a significant decrease in periodic limb movements during sleep (PLMS) and a prolonged first undisturbed sleep period. Additionally, (neuro)psychological functioning was improved on several domains. The study demonstrates that the degree of comorbidity symptoms is at least aggravated by enuresis (and/or high nocturnal diuresis rate) since sleep and (neuro)psychological functioning were significantly ameliorated by treatment of enuresis. These results indicate that enuresis is not such a benign condition as has previously been assumed.

  1. Stable beams

    CERN Multimedia

    2015-01-01

    Stable beams: two simple words that carry so much meaning at CERN. When LHC page one switched from "squeeze" to "stable beams" at 10.40 a.m. on Wednesday, 3 June, it triggered scenes of jubilation in control rooms around the CERN sites, as the LHC experiments started to record physics data for the first time in 27 months. This is what CERN is here for, and it’s great to be back in business after such a long period of preparation for the next stage in the LHC adventure.   I’ve said it before, but I’ll say it again. This was a great achievement, and testimony to the hard and dedicated work of so many people in the global CERN community. I could start to list the teams that have contributed, but that would be a mistake. Instead, I’d simply like to say that an achievement as impressive as running the LHC – a machine of superlatives in every respect – takes the combined effort and enthusiasm of everyone ...

  2. Boundary Spanning

    DEFF Research Database (Denmark)

    Zølner, Mette

    The paper explores how locals span boundaries between corporate and local levels. The aim is to better comprehend potentialities and challenges when MNCs draws on locals’ culture specific knowledge. The study is based on an in-depth, interpretive case study of boundary spanning by local actors in...... approach with pattern matching is a way to shed light on the tacit local knowledge that organizational actors cannot articulate and that an exclusively inductive research is not likely to unveil....

  3. Analysis of nocturia with 24-h urine volume, nocturnal urine volume, nocturnal bladder capacity and length of sleep duration: concept for effective treatment modality.

    Science.gov (United States)

    Udo, Yukihiro; Nakao, Masahiro; Honjo, Hisashi; Ukimura, Osamu; Kawauchi, Akihiro; Kitakoji, Hiroshi; Miki, Tsuneharu

    2011-03-01

    • To determine the relationship between the number of nocturia and 24-h urine volume, nocturnal urine volume, nocturnal bladder capacity and length of sleep duration as well as to assess the significance of these factors with respect to eliminating nocturnal voidings in individual patients with nocturia. • Among 532 participants who completed a 3-day bladder diary between April 2005 and December 2006, the diaries of 450 participants without 24-h polyuria were analyzed. • Clinical variables such as the number of daytime and night-time voids, 24-h urine volume, nocturnal polyuria index, daytime and night-time maximum voided volumes (MVV), night/day MVV ratio, sleep duration and proportion of night/day urine production rates were obtained from each diary. • Participants were classified into eight groups according to values of three factors: nocturnal MVV, proportion of night/day urine production rates and length of sleep duration. • Each group was divided into three subgroups: non-nocturics (number of nocturnal voidings is zero), mild nocturics (number of nocturnal voidings is one) and severe nocturics (number of nocturnal voidings is two or more). • The data from non-nocturics with three normal factors were regarded as the normal control and compared with the variables of the other subgroups using Dunnett's method. • Variables that form the basis of classifying participants into eight groups and corresponding to abnormal factors of each group were statistically significant in all the subgroups of each group. • Furthermore, a significantly increased 24-h urine volume was found in severe nocturics of the group with three normal factors. • A significantly decreased 24-h urine volume was found in non-nocturics of groups with nocturnal polyuria, decreased bladder capacity and both long sleep duration and nocturnal polyuria. • A significantly increased nocturnal MVV and night/day MVV ratio were shown in non-nocturics and mild nocturics of the groups

  4. Linking Dynamics of the Near-surface Flow to Deeper Boundary Layer Forcing in the Nocturnal Boundary Layer

    Science.gov (United States)

    2012-06-01

    BPP ) site in Corvallis, Oregon, USA (44◦ 34’ 1” N, 123◦ 14’ 32” W) from June until November 2010. With an elevation of 65.5 m ± 1.5 m above sea level...SODAR site. BPP site The core site, seen in Figure 3.4 as the southernmost location, consisted of the largest concentration of sensing equipment. The...were located at 7.0 meters and 1.6 meters agl. 20 (a) Site Layout (b) BPP Site FIGURE 3.4: (3.4(a)) SODAR migration pattern, note that the BPP Tower

  5. Blurring Boundaries

    DEFF Research Database (Denmark)

    Neergaard, Ulla; Nielsen, Ruth

    2010-01-01

    of welfare functions into EU law both from an internal market law and a constitutional law perspective. The main problem areas covered by the Blurring Boundaries project were studied in sub-projects on: 1) Internal market law and welfare services; 2) Fundamental rights and non-discrimination law aspects......; and 3) Services of general interest. In the Blurring Boundaries project, three aspects of the European Social Model have been particularly highlighted: the constitutionalisation of the European Social Model, its multi-level legal character, and the clash between market access justice at EU level...... and distributive justice at national level....

  6. Nocturnal raptors (owls: contributions to study of its popularity

    Directory of Open Access Journals (Sweden)

    Maria Lindelia Rincón Hernández

    2017-01-01

    Full Text Available This research characterizes the nocturnal birds of prey on the campus of Universidad Pedagógica y Tecnológica de Colombia (UPTC; in English, Pedagogical and Technological University of Colombia, in addition to the contribution to the study of its popularity, with students in fifth grade from two educational institutions, one, of the urban context, and other, of the rural context. The study involved the implementation of the didactic component to promote recognition of their biological significance in elementary school students. Among the findings two species of nocturnal birds of prey were identified: common currucutú owl (Tropical Screech Owl, Megascops choliba and the barn owl (Tyto alba, with a relative abundance of 12 individuals and 10 individuals, respectively. It also includes changes in perception from students regarding beliefs and superstitions about such species, which favors the recognition of the biological role in the ecosystem and the need for its conservation.

  7. Atmospheric boundary layers in storms: advanced theory and modelling applications

    Directory of Open Access Journals (Sweden)

    S. S. Zilitinkevich

    2005-01-01

    Full Text Available Turbulent planetary boundary layers (PBLs control the exchange processes between the atmosphere and the ocean/land. The key problems of PBL physics are to determine the PBL height, the momentum, energy and matter fluxes at the surface and the mean wind and scalar profiles throughout the layer in a range of regimes from stable and neutral to convective. Until present, the PBLs typical of stormy weather were always considered as neutrally stratified. Recent works have disclosed that such PBLs are in fact very strongly affected by the static stability of the free atmosphere and must be treated as factually stable (we call this type of the PBL "conventionally neutral" in contract to the "truly neutral" PBLs developed against the neutrally stratified free flow. It is common knowledge that basic features of PBLs exhibit a noticeable dependence on the free-flow static stability and baroclinicity. However, the concern of the traditional theory of neural and stable PBLs was almost without exception the barotropic nocturnal PBL, which develops at mid latitudes during a few hours in the night, on the background of a neutral or slightly stable residual layer. The latter separates this type of the PBL from the free atmosphere. It is not surprising that the nature of turbulence in such regimes is basically local and does not depend on the properties of the free atmosphere. Alternatively, long-lived neutral (in fact only conditionally neutral or stable PBLs, which have much more time to grow up, are placed immediately below the stably stratified free flow. Under these conditions, the turbulent transports of momentum and scalars even in the surface layer - far away from the PBL outer boundary - depend on the free-flow Brunt-Väisälä frequency, N. Furthermore, integral measures of the long-lived PBLs (their depths and the resistance law functions depend on N and also on the baroclinic shear, S. In the traditional PBL models both non-local parameters N and S

  8. Sleep disturbances in IDDM patients with nocturnal hypoglycemia

    DEFF Research Database (Denmark)

    Bendtson, I; Gade, J; Thomsen, C E

    1992-01-01

    Eight insulin-dependent diabetic patients were studied to evaluate sleep patterns during normoglycemia and spontaneous and insulin-induced hypoglycemia. Two channels of electroencephalogram (EEG), electromyogram and actooculogram were recorded. The signals were analyzed off-line, using...... a polygraphic sleep analysis system. The scoring was mainly based on the color density spectral array of the EEG. Blood glucose and growth hormone were measured serially. Asymptomatic, spontaneous nocturnal hypoglycemia occurred in 38% of the nights. Conventional sleep analysis showed a tendency toward...

  9. Nocturnal drainage wind characteristics in two converging air sheds

    International Nuclear Information System (INIS)

    Gedayloo, T.; Clements, W.E.; Barr, S.; Archuleta, J.A.

    1980-01-01

    During the short experimental period in the Grants Basin of Northeastern New Mexico a survey was conducted on the complex meteorology of this area. Emphasis was placed on the nocturnal drainage flow because of the potential hazards to the populated areas of Milan and Grants from the effluents of the uranium mining and milling operation in this area. This investigation has shown that the nocturnal drainage flow patterns agree with the winds predicted on the basis of the complex terrain of the area. Because of the surface cooling at night (over 25 0 C during summer and about 20 0 C during winter), air from elevated surrounding areas flows to the low lying regions consequently setting up a nocturnal drainage flow. This regime exists over 60% of the time during summer months and over 65% of the time during winter months with a depth generally less than 200 m. In the San Mateo air shed the drainage flow is east northeast, and in the Ambrosia Lake air shed it is from northwest. The confluence of these two air flows contributes mainly to the drainage flow through the channel formed by La Ja Mesa and Mesa Montanosa. The analysis of data collected by the recording Flats Station confirms the prediction that although the area south of the channel region broadens considerably causing a reduction in flow speed, contributions from the southside of La Jara Mesa and Mesa Montanosa partly compensate for this reduction. The position of this recording station is 15 to 20 km from the populated towns of Milan and Grants. A drainage flow speed of approximately 2.2 m s -1 and the duration of over 11 hours as recorded by this station indicates that air from the San Mateo and Ambrosia Lake regions may be transported southwards to these population centers during a nocturnal period. In order to test this prediction, a series of multi-atmospheric tracer experiments were conducted in the Grants Basin

  10. Environmental enrichment for a mixed-species nocturnal mammal exhibit.

    Science.gov (United States)

    Clark, Fay E; Melfi, Vicky A

    2012-01-01

    Environmental enrichment (EE) is an integral aspect of modern zoo animal management but, empirical evaluation of it is biased toward species housed in single-species groups. Nocturnal houses, where several nocturnal species are housed together, are particularly overlooked. This study investigated whether three species (nine-banded armadillos, Dasypus novemcinctus; Senegal bush babies, Galago senegalensis; two-toed sloths, Choloepus didactylus) in the nocturnal house at Paignton Zoo Environmental Park, UK could be enriched using food-based and sensory EE. Subjects were an adult male and female of each species. EE was deemed effective if it promoted target species-typical behaviors, behavioral diversity, and increased use of enriched exhibit zones. Results from generalized linear mixed models demonstrated that food-based EE elicited the most positive behavioral effects across species. One set of food-based EEs (Kong®, termite mound and hanging food) presented together was associated with a significant increase in species-typical behaviors, increased behavioral diversity, and increased use of enriched exhibit zones in armadillos and bush babies. Although one type of sensory EE (scented pine cones) increased overall exhibit use in all species, the other (rainforest sounds) was linked to a significant decrease in species-typical behavior in bush babies and sloths. There were no intra or interspecies conflicts over EE, and commensalism occurred between armadillos and bush babies. Our data demonstrate that simple food-based and sensory EE can promote positive behavioral changes in a mixed-species nocturnal mammal exhibit. We suggest that both food and sensory EE presented concurrently will maximize opportunities for naturalistic activity in all species. © 2011 Wiley Periodicals, Inc.

  11. Scale Modelling of Nocturnal Cooling in Urban Parks

    Science.gov (United States)

    Spronken-Smith, R. A.; Oke, T. R.

    Scale modelling is used to determine the relative contribution of heat transfer processes to the nocturnal cooling of urban parks and the characteristic temporal and spatial variation of surface temperature. Validation is achieved using a hardware model-to-numerical model-to-field observation chain of comparisons. For the calm case, modelling shows that urban-park differences of sky view factor (s) and thermal admittance () are the relevant properties governing the park cool island (PCI) effect. Reduction in sky view factor by buildings and trees decreases the drain of longwave radiation from the surface to the sky. Thus park areas near the perimeter where there may be a line of buildings or trees, or even sites within a park containing tree clumps or individual trees, generally cool less than open areas. The edge effect applies within distances of about 2.2 to 3.5 times the height of the border obstruction, i.e., to have any part of the park cooling at the maximum rate a square park must be at least twice these dimensions in width. Although the central areas of parks larger than this will experience greater cooling they will accumulate a larger volume of cold air that may make it possible for them to initiate a thermal circulation and extend the influence of the park into the surrounding city. Given real world values of s and it seems likely that radiation and conduction play almost equal roles in nocturnal PCI development. Evaporation is not a significant cooling mechanism in the nocturnal calm case but by day it is probably critical in establishing a PCI by sunset. It is likely that conditions that favour PCI by day (tree shade, soil wetness) retard PCI growth at night. The present work, which only deals with PCI growth, cannot predict which type of park will be coolest at night. Complete specification of nocturnal PCI magnitude requires knowledge of the PCI at sunset, and this depends on daytime energetics.

  12. Innovative Visualizations Shed Light on Avian Nocturnal Migration.

    Directory of Open Access Journals (Sweden)

    Judy Shamoun-Baranes

    Full Text Available Globally, billions of flying animals undergo seasonal migrations, many of which occur at night. The temporal and spatial scales at which migrations occur and our inability to directly observe these nocturnal movements makes monitoring and characterizing this critical period in migratory animals' life cycles difficult. Remote sensing, therefore, has played an important role in our understanding of large-scale nocturnal bird migrations. Weather surveillance radar networks in Europe and North America have great potential for long-term low-cost monitoring of bird migration at scales that have previously been impossible to achieve. Such long-term monitoring, however, poses a number of challenges for the ornithological and ecological communities: how does one take advantage of this vast data resource, integrate information across multiple sensors and large spatial and temporal scales, and visually represent the data for interpretation and dissemination, considering the dynamic nature of migration? We assembled an interdisciplinary team of ecologists, meteorologists, computer scientists, and graphic designers to develop two different flow visualizations, which are interactive and open source, in order to create novel representations of broad-front nocturnal bird migration to address a primary impediment to long-term, large-scale nocturnal migration monitoring. We have applied these visualization techniques to mass bird migration events recorded by two different weather surveillance radar networks covering regions in Europe and North America. These applications show the flexibility and portability of such an approach. The visualizations provide an intuitive representation of the scale and dynamics of these complex systems, are easily accessible for a broad interest group, and are biologically insightful. Additionally, they facilitate fundamental ecological research, conservation, mitigation of human-wildlife conflicts, improvement of meteorological

  13. [Is nocturnal polyuria more frequent among patients with Parkinson's disease?].

    Science.gov (United States)

    Romain, J; Torny, F; Dumas, J-P; Gamé, X; Descazeaud, A

    2015-05-01

    Nocturia is a frequent complaint in the population of idiopathic Parkinson's disease patients (IPD). The consequences of nocturia in the IPD population are at high importance as these patients have motor problems and therefore a risk of nocturnal fall. The aim of the study was to determine the mechanism of nocturia in patients with MPI, by determining the prevalence of nocturnal polyuria (NP) in this population. A prospective study by bladder diary was conducted on 70 consecutive IPD patients consulting for regular neurological follow-up at a non-severe stage. Nocturia was defined as 1 or more awakenings to urinate. Two definitions of NP were used: nocturnal diuresis 33% or higher of the total diuresis (NUV33), which is the ICS (International Continence Society) definition, and nocturnal diuresis 90 mL/h or higher (NUP90). The mean patient age was 71 years (45-86, sex ratio 33/30). On average, patients were diagnosed for IPD 6.76 years earlier. The prevalence of NP was 64.5% according to NUV33 definition, and 17.7% according to NUP90 definition. Among patients with nocturia, the prevalence of NP was 66% (NUV33) and 21.5% (NUP90). No association was observed between disease duration of the IPD and the prevalence of nocturia and NP. Patients 70 years and older were more likely to have NP as defined by NUV33 than those less than 70 years (72.7% versus 55.17%, P=0.015). Men had more frequently nocturia (33.3% versus 20.7%, P=0.027). The prevalence of NP and nocturia was analyzed in patients with IPD at a non-severe stage. This prevalence was not higher than in the general population of the same age. The mechanism of nocturia in patients with IPD is not unambiguous and therefore requires to be explored by a bladder diary. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  14. Nocturnal insects use optic flow for flight control

    OpenAIRE

    Baird, Emily; Kreiss, Eva; Wcislo, William; Warrant, Eric; Dacke, Marie

    2011-01-01

    To avoid collisions when navigating through cluttered environments, flying insects must control their flight so that their sensory systems have time to detect obstacles and avoid them. To do this, day-active insects rely primarily on the pattern of apparent motion generated on the retina during flight (optic flow). However, many flying insects are active at night, when obtaining reliable visual information for flight control presents much more of a challenge. To assess whether nocturnal flyin...

  15. Nocturnal weakly acidic reflux promotes aspiration of bile acids in lung transplant recipients.

    Science.gov (United States)

    Blondeau, Kathleen; Mertens, Veerle; Vanaudenaerde, Bart A; Verleden, Geert M; Van Raemdonck, Dirk E; Sifrim, Daniel; Dupont, Lieven J

    2009-02-01

    Gastroesophageal reflux (GER) and aspiration of bile acids have been implicated as non-alloimmune risk factors for the development of bronchiolitis obliterans syndrome (BOS) after lung transplantation. The aim of our study was to investigate the association between GER and gastric aspiration of bile acids and to establish which reflux characteristics may promote aspiration of bile acids into the lungs and may feature as a potential diagnostic tool in identifying lung transplantation (LTx) patients at risk for aspiration. Twenty-four stable LTx recipients were studied 1 year after transplantation. All patients underwent 24-hour ambulatory impedance-pH recording for the detection of acid (pH acidic (pH 4 to 7) reflux. On the same day, bronchoalveolar lavage fluid (BALF) was collected and then analyzed for the presence of bile acids (Bioquant enzymatic assay). Increased GER was detected in 13 patients, of whom 9 had increased acid reflux and 4 had exclusively increased weakly acidic reflux. Sixteen patients had detectable bile acids in the BALF (0.6 [0.4 to 1.5] micromol/liter). The 24-hour esophageal volume exposure was significantly increased in patients with bile acids compared to patients without bile acids in the BALF. Acid exposure and the number of reflux events (total, acid and weakly acidic) were unrelated to the presence of bile acids in the BALF. However, both nocturnal volume exposure and the number of nocturnal weakly acidic reflux events were significantly higher in patients with bile acids in the BALF. Weakly acidic reflux events, especially during the night, are associated with the aspiration of bile acids in LTx recipients and may therefore feature as a potential risk factor for the development of BOS.

  16. Observation of low-frequency acoustic surface waves in the nocturnal boundary layer.

    Science.gov (United States)

    Talmadge, Carrick L; Waxler, Roger; Di, Xiao; Gilbert, Kenneth E; Kulichkov, Sergey

    2008-10-01

    A natural terrain surface, because of its porosity, can support an acoustic surface wave that is a mechanical analog of the familiar vertically polarized surface wave in AM radio transmission. At frequencies of several hundred hertz, the acoustic surface wave is attenuated over distances of a few hundred meters. At lower frequencies (e.g., below approximately 200 Hz) the attenuation is much less, allowing surface waves to propagate thousands of meters. At night, a low-frequency surface wave is generally present at long ranges even when downward refraction is weak. Thus, surface waves represent a ubiquitous nighttime transmission mode that exists even when other transmission modes are weak or absent. Data from recent nighttime field experiments and theoretical calculations are presented, demonstrating the persistence of the surface wave under different meteorological conditions. The low-frequency surface wave described here is the "quasiharmonical" tail observed previously in nighttime measurements but not identified by S. Kulichkov and his colleagues (Chunchuzov, I. P. et al. 1990. "On acoustical impulse propagation in a moving inhomogeneous atmospheric layer," J. Acoust. Soc. Am. 88, 455-461).

  17. Response and sensitivity of the nocturnal boundary layer over land to added longwave radiative forcing

    NARCIS (Netherlands)

    McNider, R.T.; Steeneveld, G.J.; Holtslag, A.A.M.; Pielke sr., R.A.; Mackaro, S.; Pour Biazar, A.; Walters, J.; Nair, U.; Christy, J.

    2012-01-01

    One of the most significant signals in the thermometer-observed temperature record since 1900 is the decrease in the diurnal temperature range over land, largely due to rising of the minimum temperatures. Generally, climate models have not well replicated this change in diurnal temperature range.

  18. Social support and nocturnal blood pressure dipping: a systematic review.

    Science.gov (United States)

    Fortmann, Addie L; Gallo, Linda C

    2013-03-01

    Attenuated nocturnal blood pressure (BP) dipping is a better predictor of cardiovascular disease (CVD) morbidity and mortality than resting BP measurements. Studies have reported associations between social support, variously defined, and BP dipping. A systematic review of the literature was conducted to investigate associations of functional and structural social support with nocturnal BP dipping assessed over a minimum of 24 hours. A total of 297 articles were identified. Of these, 11 met criteria for inclusion; all studies were cross-sectional in design and included adult participants only (mean age = 19 to 72 years). Evidence was most consistent for an association between functional support and BP dipping, such that 5 of 7 studies reported statistically (or marginally) significant positive associations with BP dipping. Statistically significant functional support-BP dipping associations were moderate (standardized effect size (d) = 0.41) to large (d = 2.01) in magnitude. Studies examining structural support were fewer and relatively less consistent; however, preliminary evidence was observed for associations of marital status and social contact frequency with BP dipping. Statistically significant structural support findings were medium (d = 0.53) to large (d = 1.13) in magnitude. Overall, findings suggest a link between higher levels of functional support and greater nocturnal BP dipping; preliminary evidence was also observed for the protective effects of marriage and social contact frequency. Nonetheless, the relatively small number of studies conducted to date and the heterogeneity of findings across meaningful subgroups suggest that additional research is needed to substantiate these conclusions.

  19. Targeting nocturnal hypertension in type 2 diabetes mellitus.

    Science.gov (United States)

    Rossen, Niklas Blach; Knudsen, Søren Tang; Fleischer, Jesper; Hvas, Anne-Mette; Ebbehøj, Eva; Poulsen, Per Løgstrup; Hansen, Klavs Würgler

    2014-11-01

    Several studies in different populations have suggested that nighttime blood pressure (BP) is a stronger predictor of cardiovascular events than daytime BP. Consequently, treatment strategies to target nighttime BP have come into focus. The aim of the present study was to investigate the effect of change of administration time of antihypertensive drugs. We included 41 patients with type 2 diabetes mellitus and nocturnal hypertension (nighttime systolic BP >120 mm Hg) in an open-label, crossover study. Patients were randomized to 8 weeks of either morning or bedtime administration of all of the individual's once-daily antihypertensive drugs, followed by 8 weeks of switched dosing regimen. Bedtime administration of antihypertensive drugs resulted in a significant reduction in nighttime (7.5 mm Hg; Pdiabetes mellitus and nocturnal hypertension, administration of once-daily antihypertensive drugs at bedtime may be favorable. The increased nocturnal natriuresis may reflect increased effect of bedtime-administered thiazides and renin-angiotensin system inhibitors, suggesting a potential mechanism of the observed effects on BP with chronotherapeutic intervention. © 2014 American Heart Association, Inc.

  20. Nocturnal sleep pattern in native Brazilian Terena adults

    Directory of Open Access Journals (Sweden)

    REIMÃO RUBENS

    2000-01-01

    Full Text Available Social-economic factors influence sleep habits. This research analyzes characteristics of nocturnal sleep in Brazilian Native Terena adults. Sixty-four adults (31 M; 33 F from 18 to 75 years, with a mean age of 37.0, from the Indian Reservation village of Córrego do Meio, in the central region of Mato Grosso do Sul, an agriculturally oriented group were evaluated. Nocturnal sleep characteristics were evaluated by means of a standard questionnaire applied to each individual. It was observed that reported nocturnal sleep was longer, sleep onset was earlier and wake up time was also earlier than usually described in urban populations. The mean total time in bed was 8.5 h or more, in every age bracket. The seven-day prevalence rate of insomnia was 4.6%, while the seven-day prevalence rate of hypnotic use was 1.5%, both remarkably less than described in urban populations. These findings stress the need to consider ethnic influences on sleep patterns and disorders.

  1. Mobile Disdrometer Observations of Nocturnal Mesoscale Convective Systems During PECAN

    Science.gov (United States)

    Bodine, D. J.; Rasmussen, K. L.

    2015-12-01

    Understanding microphysical processes in nocturnal mesoscale convective systems (MCSs) is an important objective of the Plains Elevated Convection At Night (PECAN) experiment, which occurred from 1 June - 15 July 2015 in the central Great Plains region of the United States. Observations of MCSs were collected using a large array of mobile and fixed instrumentation, including ground-based radars, soundings, PECAN Integrated Sounding Arrays (PISAs), and aircraft. In addition to these observations, three mobile Parsivel disdrometers were deployed to obtain drop-size distribution (DSD) measurements to further explore microphysical processes in convective and stratiform regions of nocturnal MCSs. Disdrometers were deployed within close range of a multiple frequency network of mobile and fixed dual-polarization radars (5 - 30 km range), and near mobile sounding units and PISAs. Using mobile disdrometer and multiple-wavelength, dual-polarization radar data, microphysical properties of convective and stratiform regions of MCSs are investigated. The analysis will also examine coordinated Range-Height Indicator (RHI) scans over the disdrometers to elucidate vertical DSD structure. Analysis of dense observations obtained during PECAN in combination with mobile disdrometer DSD measurements contributes to a greater understanding of the structural characteristics and evolution of nocturnal MCSs.

  2. Experimental temperature manipulations alter songbird autumnal nocturnal migratory restlessness

    Directory of Open Access Journals (Sweden)

    Berchtold Adrienne

    2017-02-01

    Full Text Available Migrating birds may respond to a variety of environmental cues in order to time migration. During the migration season nocturnally migrating songbirds may migrate or stop-over at their current location, and when migrating they may vary the rate or distance of migration on any given night. It has long been known that a variety of weather-related factors including wind speed and direction, and temperature, are correlated with migration in free-living birds, however these variables are often correlated with each other. In this study we experimentally manipulated temperature to determine if it would directly modulate nocturnal migratory restlessness in songbirds. We experimentally manipulated temperature between 4, 14, and 24°C and monitored nocturnal migratory restlessness during autumn in white-throated sparrows (Zonotrichia albicollis. White-throated sparrows are relatively shortdistance migrants with a prolonged autumnal migration, and we thus predicted they might be sensitive to weatherrelated cues when deciding whether to migrate or stopover. At warm temperatures (24°C none of the birds exhibited migratory restlessness. The probability of exhibiting migratory restlessness, and the intensity of this restlessness (number of infra-red beam breaks increased at cooler (14°C, 4°C temperatures. These data support the hypothesis that one of the many factors that birds use when making behavioural decisions during migration is temperature, and that birds can respond to temperature directly independently of other weather-related cues.

  3. A novel once daily microparticulate dosage form comprising lansoprazole to prevent nocturnal acid breakthrough in the case of gastro-esophageal reflux disease: preparation, pharmacokinetic and pharmacodynamic evaluation.

    Science.gov (United States)

    Alai, Milind; Lin, Wen Jen

    2013-01-01

    The objective of this study was to formulate and evaluate the lansoprazole (LPZ)-loaded microparticles to prevent nocturnal acid breakthrough in the case of gastro-esophageal reflux disease (GERD). The microparticulate delivery system was prepared by solvent evaporation method using Eudragit RS100 as a matrix polymer followed by enteric coated with Eudragit S100 and hydroxypropyl methylcellulose phthalate HP55 using spray drying method. The enteric coated microparticles were stable in gastric pH condition. In vivo pharmacokinetic and pharmacodynamic studies in male Wistar rats demonstrated that enteric coated microparticles sustained release of LPZ and promoted ulcer healing activity. In other words, the microparticulate dosage form provided effective drug concentration for a longer period as compared to conventional extended release dosage form, and showed sufficient anti-acid secretion activity to treat acid related disorders including the enrichment of nocturnal acid breakthrough event based on a once daily administration.

  4. The structure of the stably stratified internal boundary layer in offshore flow over the sea

    Science.gov (United States)

    Garratt, J. R.; Ryan, B. F.

    1989-04-01

    Observations obtained mainly from a research aircraft are presented of the mean and turbulent structure of the stably stratified internal boundary layer (IBL) over the sea formed by warm air advection from land to sea. The potential temperature and humidity fields reveal the vertical extent of the IBL, for fetches out to several hundred of kilometres, geostrophic winds of 20 25 m s-1, and potential temperature differences between undisturbed continental air and the sea surface of 7 to 17 K. The dependence of IBL depth on these external parameters is discussed in the context of the numerical results of Garratt (1987), and some discrepancies are noted. Wind observations show the development of a low-level wind maximum (wind component normal to the coast) and rotation of the wind to smaller cross-isobar flow angles. Potential temperature (θ) profiles within the IBL reveal quite a different structure to that found in the nocturnal boundary layer (NBL) over land. Over the sea, θ profiles have large positive curvature with vertical gradients increasing monotonically with height; this reflects the dominance of turbulent cooling within the layer. The behaviour is consistent with known behaviour in the NBL over land where curvature becomes negative (vertical gradients of θ decreasing with height) as radiative cooling becomes dominant. Turbulent properties are discussed in terms of non-dimensional quantities, normalised by the surface friction velocity, as functions of normalised height using the IBL depth. Vertical profiles of these and the normalised wavelength of the spectral maximum agree well with known results for the stable boundary layer over land (Caughey et al., 1979).

  5. The atmospheric boundary layer evening transitions: an observational and numerical study from two different datasets

    Science.gov (United States)

    Sastre, Mariano; Yagüe, Carlos; Román-Cascón, Carlos; Maqueda, Gregorio; Ander Arrillaga, Jon

    2015-04-01

    In this work we study the temporal evolution of the Atmospheric Boundary Layer (ABL) along the transition period from a diurnal typical convection to a nocturnal more frequently stable situation. This period is known as late afternoon or evening transition, depending on the specific definitions employed by different authors [1]. In order to obtain a proper characterization, we try to learn whether or not the behaviour of these transitional boundary layers is strongly dependent on local conditions. To do so, two sets of evening transitions are studied from data collected at two different experimental sites. These locations correspond to research facilities named CIBA (Spain) and CRA (France), which are the places where atmospheric field campaigns have been conducted during the last years, such as CIBA2008 and BLLAST 2011, respectively. In order to get comparable situations, we focus especially on transitions with weak synoptic forcing, and consider daily astronomical sunset as a reference time. A statistical analysis on main parameters related to the transition is carried out for both locations, and the average behaviour is shown as well as extreme values according to the timing. A similar pattern in the qualitative evolution of many variables is found. Nevertheless, several relevant differences in the progress of key variables are obtained too. Moisture, both from the soil and the air, is thought to have great relevance in explaining many of the differences found between the two sites. Some case studies are explored, focusing on the role played by the atmospheric turbulence. Complementary, numerical experiments are also performed using the Weather Research and Forecast (WRF) mesoscale model, in order to test the role of humidity, by artificially varying it in some of the simulations. [1] Lothon, M. and coauthors (2014): The BLLAST field experiment: Boundary-Layer Late Afternoon and Sunset Turbulence. Atmos. Chem. Phys., 14, 10931-10960.

  6. Climatology of nocturnal low-level jets over North Africa and implications for modeling mineral dust emission.

    Science.gov (United States)

    Fiedler, S; Schepanski, K; Heinold, B; Knippertz, P; Tegen, I

    2013-06-27

    [1] This study presents the first climatology for the dust emission amount associated with Nocturnal Low-Level Jets (NLLJs) in North Africa. These wind speed maxima near the top of the nocturnal boundary layer can generate near-surface peak winds due to shear-driven turbulence in the course of the night and the NLLJ breakdown during the following morning. The associated increase in the near-surface wind speed is a driver for mineral dust emission. A new detection algorithm for NLLJs is presented and used for a statistical assessment of NLLJs in 32 years of ERA-Interim reanalysis from the European Centre for Medium-Range Weather Forecasts. NLLJs occur in 29% of the nights in the annual and spatial mean. The NLLJ climatology shows a distinct annual cycle with marked regional differences. Maxima of up to 80% NLLJ frequency are found where low-level baroclinicity and orographic channels cause favorable conditions, e.g., over the Bodélé Depression, Chad, for November-February and along the West Saharan and Mauritanian coast for April-September. Downward mixing of NLLJ momentum to the surface causes 15% of mineral dust emission in the annual and spatial mean and can be associated with up to 60% of the total dust amount in specific areas, e.g., the Bodélé Depression and south of the Hoggar-Tibesti Channel. The sharp diurnal cycle underlines the importance of using wind speed information with high temporal resolution as driving fields for dust emission models. Citation: Fiedler, S., K. Schepanski, B. Heinold, P. Knippertz, and I. Tegen (2013), Climatology of nocturnal low-level jets over North Africa and implications for modeling mineral dust emission, J. Geophys. Res. Atmos., 118, 6100-6121, doi:10.1002/jgrd.50394.

  7. A case study of the development of nocturnal slope flows in a wide open valley and associated air quality implications

    Energy Technology Data Exchange (ETDEWEB)

    Pardyjak, Eric R. [Utah Univ., Salt Lake City, UT (United States). Dept. of Mechanical Engineering; Fernando, Harindra Joseph S.; Anderson, James [Arizona State Univ., Tempe, AZ (United States). Center for Environmental Fluid Dynamics; Hunt, Julian C.R. [University Coll., London (United Kingdom). Dept. of Space and Climate Physics, and Earth Sciences; Grachev, Andrey A. [Colorado Univ./NOAA, Boulder, CO (US). Cooperative Inst. for Research in Environmental Sciences (CIRES)

    2009-07-01

    This paper documents the development of nocturnal flows in the wide open Phoenix, Arizona (U.S.A) valley (30 km x 100 km) that is bordered by a large nearly flat plain to the west and high mountains to the north and east. Local thermally driven winds concomitant with the absence of significant synoptic pressure gradients dominate typical winter conditions in the Phoenix valley. The purpose of the Phoenix Air Flow Experiment (PAFEX-1) was to study the development of thermally driven flows during the evening transition in a sloping valley and describe the general pattern of transport and dispersion of contaminants during transition periods and at night. Measurements were made using a tethered balloon, sonic anemometer, balloon-based aerosol sampler, radiation sensors, cup anemometers, thermistors and humidity sensors in conjunction with data collected from 44 standard meteorological stations located throughout the valley. Over the period of 15 days in January and February 1998 the general diurnal flow patterns were repeatable, but varied substantially around the valley. This paper focuses on a case study of the evening transition, nocturnal circulation and morning breakdown of the nocturnal circulation on the night of 31 January and morning of 1 February. Central valley measurements were consistent with the notion that the evening transition is associated with a moving front, followed by intense mixing and the movement of the front to establish down-valley winds. Flows originating from different slopes led to the arrival of fronts at the various measurement locations at different times. These flows intrude into the valley and interact with each other, often causing multi-layered vertical structure. The intrusions respond to the evolving stratification and cause striking variability of these layers, for example, periodic wind and temperature disturbances corresponding to the arrival of new intrusive fronts. The evolution of the boundary layer was found to have a

  8. Impact of nocturnal heartburn on quality of life, sleep, and productivity: the SINERGE study.

    Science.gov (United States)

    Calleja, José Luis; Bixquert, M; Maldonado, J

    2007-10-01

    The aim of the SINERGE study was to assess the impact of nocturnal heartburn on quality of life, sleep, and productivity. Ambulatory patients >/=18 years old and classified as defined cases of nocturnal heartburn (n=337), nonnocturnal heartburn (n=139), uncontrolled hypertension (n=198), and symptomatic depression (n=104) were included in this cross-sectional study. Information on age, gender, body mass index, and comorbidity was collected and the following validated questionnaires were applied: SF-12, Pittsburgh Sleep Quality Index, and Work Productivity and Activity Impairment questionnaire. The prevalence of primary care consultation for heartburn and nocturnal heartburn was 4.7% and 1.9%, respectively. Health-related quality of life, sleep, and productivity were significantly impaired in patients with frequent nocturnal heartburn symptoms as compared with those of the patients without nocturnal symptoms or patients with hypertension. Nocturnal heartburn poses a considerable burden for the sufferer because of the impact on quality of life, sleep, and daily activities.

  9. Neuropsychological functioning related to specific characteristics of nocturnal enuresis.

    Science.gov (United States)

    Van Herzeele, C; Dhondt, K; Roels, S P; Raes, A; Groen, L-A; Hoebeke, P; Walle, J Vande

    2015-08-01

    There is a high comorbidity demonstrated in the literature between nocturnal enuresis and several neuropsychological dysfunctions, with special emphasis on attention deficit hyperactivity disorder (ADHD). However, the majority of the psychological studies did not include full non-invasive screening and failed to differentiate between monosymptomatic nocturnal enuresis (MNE) and non-MNE patients. The present study primarily aimed to investigate the association between nocturnal enuresis and (neuro)psychological functioning in a selective homogeneous patient group, namely: children with MNE and associated nocturnal polyuria (NP). Secondly, the study investigated the association between specific characteristics of nocturnal enuresis (maximum voided volume, number of wet nights and number of nights with NP) and ADHD-inattentive symptoms, executive functioning and quality of life. The psychological measurements were multi-informant (parents, children and teachers) and multi-method (questionnaires, clinical interviews and neuropsychological testing). Thirty children aged 6-16 years (mean 10.43 years, SD 3.08) were included. Of them, 80% had at least one psychological, motor or neurological difficulty. The comorbid diagnosis of ADHD, especially the predominantly inattentive presentation, was most common. According to the teachers, a low maximum voided volume (corrected for age) was associated with more attention problems, and a high number of nights with NP was associated with more behaviour-regulation problems. No significant correlations were found between specific characteristics of enuresis and quality of life. Details are demonstrated in Table. The children were recruited from a tertiary referral centre, which resulted in selection bias. Moreover, NP was defined as a urine output exceeding 100% of the expected bladder capacity for age (EBC), and not according to the expert-opinion-based International Children's Continence Society norm of 130% of EBC. The definition

  10. Determining water sources in the boundary layer from tall tower profiles of water vapor and surface water isotope ratios after a snowstorm in Colorado

    Directory of Open Access Journals (Sweden)

    D. Noone

    2013-02-01

    Full Text Available The D/H isotope ratio is used to attribute boundary layer humidity changes to the set of contributing fluxes for a case following a snowstorm in which a snow pack of about 10 cm vanished. Profiles of H2O and CO2 mixing ratio, D/H isotope ratio, and several thermodynamic properties were measured from the surface to 300 m every 15 min during four winter days near Boulder, Colorado. Coeval analysis of the D/H ratios and CO2 concentrations find these two variables to be complementary with the former being sensitive to daytime surface fluxes and the latter particularly indicative of nocturnal surface sources. Together they capture evidence for strong vertical mixing during the day, weaker mixing by turbulent bursts and low level jets within the nocturnal stable boundary layer during the night, and frost formation in the morning. The profiles are generally not well described with a gradient mixing line analysis because D/H ratios of the end members (i.e., surface fluxes and the free troposphere evolve throughout the day which leads to large uncertainties in the estimate of the D/H ratio of surface water flux. A mass balance model is constructed for the snow pack, and constrained with observations to provide an optimal estimate of the partitioning of the surface water flux into contributions from sublimation, evaporation of melt water in the snow and evaporation from ponds. Results show that while vapor measurements are important in constraining surface fluxes, measurements of the source reservoirs (soil water, snow pack and standing liquid offer stronger constraint on the surface water balance. Measurements of surface water are therefore essential in developing observational programs that seek to use isotopic data for flux attribution.

  11. Circadian Rhythm of Glomerular Filtration and Solute Handling Related to Nocturnal Enuresis.

    Science.gov (United States)

    Dossche, L; Raes, A; Hoebeke, P; De Bruyne, P; Vande Walle, J

    2016-01-01

    Although nocturnal polyuria in patients with monosymptomatic enuresis can largely be explained by the decreased nocturnal vasopressin secretion hypothesis, other circadian rhythms in the kidney also seem to have a role. We recently documented an absent day/night rhythm in a subgroup of desmopressin refractory cases. We explore the importance of abnormal circadian rhythm of glomerular filtration and tubular (sodium, potassium) parameters in patients with monosymptomatic enuresis. In this retrospective study of a tertiary enuresis population we collected data subsequent to a standardized screening (International Children's Continence Society questionnaire), 14-day diary for nocturnal enuresis and diuresis, and 24-hour concentration profile. The study population consisted of 139 children with nocturnal enuresis who were 5 years or older. Children with nonmonosymptomatic nocturnal enuresis were used as controls. There was a maintained circadian rhythm of glomerular filtration, sodium, osmotic excretion and diuresis rate in children with monosymptomatic and nonmonosymptomatic nocturnal enuresis, and there was no difference between the 2 groups. Secondary analysis revealed that in patients with nocturnal polyuria (with monosymptomatic or nonmonosymptomatic nocturnal enuresis) circadian rhythm of glomerular filtration, sodium and osmotic excretion, and diuresis rate was diminished in contrast to those without nocturnal polyuria (p Circadian rhythm of the kidney does not differ between patients with nonmonosymptomatic and monosymptomatic enuresis. However, the subgroup with enuresis and nocturnal polyuria has a diminished circadian rhythm of nocturnal diuresis, sodium excretion and glomerular filtration in contrast to children without nocturnal polyuria. This observation cannot be explained by the vasopressin theory alone. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  12. Does the Age of Donor Kidneys Affect Nocturnal Polyuria in Patients With Successful Real Transplantation?

    Science.gov (United States)

    Mitsui, T; Morita, K; Iwami, D; Kitta, T; Kanno, Y; Moriya, K; Takeda, M; Shinohara, N

    We investigated whether the age of donor kidneys influences the incidence of nocturnal polyuria in patients with successful renal transplantation (RTX). Eighty-five patients (45 men and 40 women) undergoing RTX (median age, 47 years) were included in this study. Twenty-four-hour bladder diaries were kept for 3 days, and nocturnal polyuria was defined as a nocturnal polyuria index (nocturnal urine volume/24-hour urine volume) of >0.33. Risk factors for nocturnal polyuria were analyzed in patients with RTX by means of the Mann-Whitney U test, χ 2 test, and a logistic regression analysis. End-stage renal disease (ESRD) developed from diabetes mellitus in 16 patients (19%). Sixty-five patients (76%) received pre-transplant dialysis, with a median duration of 5 years. The median serum creatinine level and body mass index at the most recent visit were 1.2 mg/dL and 21.2 kg/m 2 , respectively. On the basis of the 24-hour bladder diaries, nocturnal polyuria was identified in 48 patients (56%). A logistic regression analysis revealed that diabetes mellitus as the original disease for ESRD was the only risk factor for nocturnal polyuria (odds ratio, 8.95; 95% confidence interval, 2.01-65.3; P = .0028). The age of donor kidneys at examination did not affect the incidence of nocturnal polyuria (P = .9402). Nocturnal polyuria was not uncommon in patients with successful RTX. Diabetes mellitus as the original disease for ESRD was the only risk factor for nocturnal polyuria, whereas the age of donor kidneys at examination did not affect the incidence of nocturnal polyuria. Thus, nocturnal polyuria is caused by recipient factors but not donor factors. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. The relationship between nocturnal polyuria and the distribution of body fluid: assessment by bioelectric impedance analysis.

    Science.gov (United States)

    Torimoto, Kazumasa; Hirayama, Akihide; Samma, Shoji; Yoshida, Katsunori; Fujimoto, Kiyohide; Hirao, Yoshihiko

    2009-01-01

    Increased nocturnal urinary volume is closely associated with nocturia. We investigated the relationship between nocturnal polyuria and the variation of body fluid distribution during the daytime using bioelectric impedance analysis. A total of 34 men older than 60 years were enrolled in this study. A frequency volume chart was recorded. Nocturnal polyuria was defined as a nocturnal urine volume per 24-hour production of greater than 0.35 (the nocturnal polyuria index). Bioelectric impedance analysis was performed 4 times daily at 8 and 11 a.m., and 5 and 9 p.m. using an InBody S20 body composition analyzer (BioSpace, Seoul, Korea). A significant difference was found in mean +/- SEM 24-hour urine production per fat-free mass between the groups with and without nocturnal polyuria (17.8 +/- 1.4 vs 7.7 +/- 0.9 ml/kg). The increase in fluid in the legs compared with the volume at 8 a.m. was significantly larger at 5 p.m., while there was no difference in the arms or trunk. Nocturnal urine volume significantly correlated with the difference in fluid volume in the legs (r = 0.527, p = 0.0019) and extracellular fluid volume (r = 0.3844, p = 0.0248) between the volumes at 8 a.m. and 9 p.m. Overproduction of urine per fat-free mass leads to nocturnal polyuria. Extracellular fluid accumulates as edema in the legs during the day in patients with nocturnal polyuria. The volume of accumulated extracellular fluid correlates with nocturnal urine volume. We suggest that leg edema is the source of nocturnal urine volume and decreasing edema may cure nocturnal polyuria.

  14. Technical advances in flow cytometry-based diagnosis and monitoring of paroxysmal nocturnal hemoglobinuria

    Science.gov (United States)

    Correia, Rodolfo Patussi; Bento, Laiz Cameirão; Bortolucci, Ana Carolina Apelle; Alexandre, Anderson Marega; Vaz, Andressa da Costa; Schimidell, Daniela; Pedro, Eduardo de Carvalho; Perin, Fabricio Simões; Nozawa, Sonia Tsukasa; Mendes, Cláudio Ernesto Albers; Barroso, Rodrigo de Souza; Bacal, Nydia Strachman

    2016-01-01

    ABSTRACT Objective: To discuss the implementation of technical advances in laboratory diagnosis and monitoring of paroxysmal nocturnal hemoglobinuria for validation of high-sensitivity flow cytometry protocols. Methods: A retrospective study based on analysis of laboratory data from 745 patient samples submitted to flow cytometry for diagnosis and/or monitoring of paroxysmal nocturnal hemoglobinuria. Results: Implementation of technical advances reduced test costs and improved flow cytometry resolution for paroxysmal nocturnal hemoglobinuria clone detection. Conclusion: High-sensitivity flow cytometry allowed more sensitive determination of paroxysmal nocturnal hemoglobinuria clone type and size, particularly in samples with small clones. PMID:27759825

  15. Microstructure of Turbulence in the Stably Stratified Boundary Layer

    Science.gov (United States)

    Sorbjan, Zbigniew; Balsley, Ben B.

    2008-11-01

    The microstructure of a stably stratified boundary layer, with a significant low-level nocturnal jet, is investigated based on observations from the CASES-99 campaign in Kansas, U.S.A. The reported, high-resolution vertical profiles of the temperature, wind speed, wind direction, pressure, and the turbulent dissipation rate, were collected under nocturnal conditions on October 14, 1999, using the CIRES Tethered Lifting System. Two methods for evaluating instantaneous (1-sec) background profiles are applied to the raw data. The background potential temperature is calculated using the “bubble sort” algorithm to produce a monotonically increasing potential temperature with increasing height. Other scalar quantities are smoothed using a running vertical average. The behaviour of background flow, buoyant overturns, turbulent fluctuations, and their respective histograms are presented. Ratios of the considered length scales and the Ozmidov scale are nearly constant with height, a fact that can be applied in practice for estimating instantaneous profiles of the dissipation rate.

  16. Sublayer of Prandtl Boundary Layers

    Science.gov (United States)

    Grenier, Emmanuel; Nguyen, Toan T.

    2018-03-01

    The aim of this paper is to investigate the stability of Prandtl boundary layers in the vanishing viscosity limit {ν \\to 0} . In Grenier (Commun Pure Appl Math 53(9):1067-1091, 2000), one of the authors proved that there exists no asymptotic expansion involving one of Prandtl's boundary layer, with thickness of order {√{ν}} , which describes the inviscid limit of Navier-Stokes equations. The instability gives rise to a viscous boundary sublayer whose thickness is of order {ν^{3/4}} . In this paper, we point out how the stability of the classical Prandtl's layer is linked to the stability of this sublayer. In particular, we prove that the two layers cannot both be nonlinearly stable in L^∞. That is, either the Prandtl's layer or the boundary sublayer is nonlinearly unstable in the sup norm.

  17. Boundary-layer processes: key findings from MATERHORN-X field campaigns

    Science.gov (United States)

    Di Sabatino, Silvana; Leo, Laura S.; Pardyjak, Eric R.; Fernando, Harindra JS

    2017-04-01

    Understanding of atmospheric boundary-layer processes in complex terrain continues to be an active area of research considering its profound implications on numerical weather prediction (WP). It is largely recognized that nocturnal circulation, non-stationary processes involved in evening and morning transitions as well gusty conditions near mountains are poorly captured by current WP models. The search for novel understanding of boundary-layer phenomena especially in critical conditions for WP models has been one of the goals of the interdisciplinary Mountain Terrain Atmospheric Modeling and Observations (MATERHORN) program (2011-2016). The program developed with four main pillars: modelling (MATERHORN-M), experiments (MATERHORN-X), technology (MATERHORN-T), and parameterizations (MATERHORN-P), all synergistically working to meet new scientific challenges, address them effectively through dedicated field and laboratory studies, and transfer the acquired knowledge for model improvements. Specifically, MATERHORN-X is at the core of the MATERHORN program. It was built upon two major field experiments carried out in 31 September-October 2012 and in May 2013 at the Granite Mountain Atmospheric Science Testbed 32 (GMAST) of the Dugway Proving Ground (DPG). In this talk we will focus on results of data analyses from MATERHORN-X with emphasis on several aspects of the nocturnal circulation under low synoptic forcing when stable stratification occurs. The first part of the talk will discuss the evolution of nocturnal flows including both evening transitions on slopes and valleys as well as the occurrence of isolated flow bursts under very stable conditions. As far as the former is concerned we report on our latest understanding of mechanisms leading to evening transitions (e.g. shadow front, slab flow, and transitional front). As far as the latter is concerned, it is hypothesized that a link exists between isolated bursts in turbulent kinetic energy and low-level jets

  18. On relevant boundary perturbations of unitary minimal models

    International Nuclear Information System (INIS)

    Recknagel, A.; Roggenkamp, D.; Schomerus, V.

    2000-01-01

    We consider unitary Virasoro minimal models on the disk with Cardy boundary conditions and discuss deformations by certain relevant boundary operators, analogous to tachyon condensation in string theory. Concentrating on the least relevant boundary field, we can perform a perturbative analysis of renormalization group fixed points. We find that the systems always flow towards stable fixed points which admit no further (non-trivial) relevant perturbations. The new conformal boundary conditions are in general given by superpositions of 'pure' Cardy boundary conditions

  19. Assessment of nocturnal aerosol optical depth from lunar photometry at the Izaña high mountain observatory

    Directory of Open Access Journals (Sweden)

    Á. Barreto

    2017-08-01

    Full Text Available This work is a first approach to correct the systematic errors observed in the aerosol optical depth (AOD retrieved at nighttime using lunar photometry and calibration techniques dependent on the lunar irradiance model. To this end, nocturnal AOD measurements were performed in 2014 using the CE318-T master Sun–sky–lunar photometer (lunar Langley calibrated at the Izaña high mountain observatory. This information has been restricted to 59 nights characterized as clean and stable according to lidar vertical profiles. A phase angle dependence as well as an asymmetry within the Moon's cycle of the Robotic Lunar Observatory (ROLO model could be deduced from the comparison in this 59-night period of the CE318-T calibration performed by means of the lunar Langley calibration and the calibration performed every single night by means of the common Langley technique. Nocturnal AOD has also been compared in the same period with a reference AOD based on daylight AOD extracted from the AErosol RObotic NETwork (AERONET at the same station. Considering stable conditions, the difference ΔAODfit, between AOD from lunar observations and the linearly interpolated AOD (the reference from daylight data, has been calculated. The results show that ΔAODfit values are strongly affected by the Moon phase and zenith angles. This dependency has been parameterized using an empirical model with two independent variables (Moon phase and zenith angles in order to correct the AOD for these residual dependencies. The correction of this parameterized dependency has been checked at four stations with quite different environmental conditions (Izaña, Lille, Carpentras and Dakar showing a significant reduction of the AOD dependence on phase and zenith angles and an improved agreement with daylight reference data. After the correction, absolute AOD differences for day–night–day clean and stable transitions remain below 0.01 for all wavelengths.

  20. Nocturnal polyuria is related to absent circadian rhythm of glomerular filtration rate.

    Science.gov (United States)

    De Guchtenaere, A; Vande Walle, C; Van Sintjan, P; Raes, A; Donckerwolcke, R; Van Laecke, E; Hoebeke, P; Vande Walle, J

    2007-12-01

    Monosymptomatic nocturnal enuresis is frequently associated with nocturnal polyuria and low urinary osmolality during the night. Initial studies found decreased vasopressin levels associated with low urinary osmolality overnight. Together with the documented desmopressin response, this was suggestive of a primary role for vasopressin in the pathogenesis of enuresis in the absence of bladder dysfunction. Recent studies no longer confirm this primary role of vasopressin. Other pathogenetic factors such as disordered renal sodium handling, hypercalciuria, increased prostaglandins and/or osmotic excretion might have a role. So far, little attention has been given to abnormalities in the circadian rhythm of glomerular filtration rate. We evaluated the circadian rhythm of glomerular filtration rate and diuresis in children with desmopressin resistant monosymptomatic nocturnal enuresis and nocturnal polyuria. We evaluated 15 children (9 boys) 9 to 14 years old with monosymptomatic nocturnal enuresis and nocturnal polyuria resistant to desmopressin treatment. The control group consisted of 25 children (12 boys) 9 to 16 years old with monosymptomatic nocturnal enuresis without nocturnal polyuria. Compared to the control population, children with nocturnal polyuria lost their circadian rhythm not only for diuresis and sodium excretion but also for glomerular filtration rate. Patients with monosymptomatic nocturnal enuresis and nocturnal polyuria lack a normal circadian rhythm for diuresis and sodium excretion, and the circadian rhythm of glomerular filtration rate is absent. This absence of circadian rhythm of glomerular filtration rate and/or sodium handling cannot be explained by a primary role of vasopressin, but rather by a disorder in circadian rhythm of renal glomerular and/or tubular functions.

  1. The risk of hyponatremia with desmopressin use for nocturnal polyuria.

    Science.gov (United States)

    Choi, Eun Young; Park, Joon-Sung; Kim, Yong Tae; Park, Sung Yul; Kim, Gheun-Ho

    2015-01-01

    Desmopressin is used for treating nocturnal polyuria, but hyponatremia is an associated concern in the elderly due to impaired urinary dilution. This study was undertaken to characterize hyponatremia occurring in adults using desmopressin for nocturnal polyuria. Data from 172 patients who were prescribed desmopressin for nocturnal polyuria at a urology clinic from September 2010 through February 2013 were retrospectively analyzed. Demographic and laboratory parameters were investigated to examine the risk factors for desmopressin-associated hyponatremia. The average follow-up serum sodium measured 21 ± 22 days after using desmopressin was 138 ± 5 mmol/l. Hyponatremia (<135 mmol/l) was found in 24 patients (14%), and it was severe in 7 (<126 mmol/l). In the hyponatremic patients, serum sodium decreased by 11 ± 6 mmol/l. Patients with hyponatremia were older than those with normonatremia (78 ± 7 vs. 68 ± 9 years, p < 0.0001). The presence of either hyponatremia-predisposing comorbidities or concurrent medications was associated with hyponatremia. Patients with hyponatremia had lower basal hemoglobin (11 ± 2 vs. 13 ± 2 g/dl, p < 0.001) and serum sodium (139 ± 2 vs. 140 ± 2 mmol/l, p < 0.05) than those with normonatremia. Multivariate logistic regression after adjustment for basal serum sodium showed that advanced age (OR 1.15; 95% CI 1.03-1.27) and lower hemoglobin level (OR 0.64; 95% CI 0.43-0.94) were independently associated with hyponatremia. Hyponatremia is not infrequently associated with desmopressin use. Those with advanced age (≥65 years) and lower hemoglobin are at risk of desmopressin-associated hyponatremia and need to be carefully monitored. © 2015 S. Karger AG, Basel.

  2. On the Restriction of the Location of Stable Points for Generalized Lotka-Volterra

    OpenAIRE

    Livesay, Michael Richard

    2017-01-01

    We develop tools to determine which fixed points in a generalized Lotka-Volterra system are stable, under certain non-degeneracy conditions. We characterize which faces of the boundary of the domain of the Lotka-Volterra system could contain a stable fixed point. Under various relaxed conditions, we show that whenever a face of the boundary contains a stable point there are no other stable points in any strictly larger face of the boundary.

  3. Boundary issues

    Science.gov (United States)

    Townsend, Alan R.; Porder, Stephen

    2011-03-01

    What is our point of no return? Caesar proclaimed 'the die is cast' while crossing the Rubicon, but rarely does modern society find so visible a threshold in our continued degradation of ecosystems and the services they provide. Humans have always used their surroundings to make a living— sometimes successfully, sometimes not (Diamond 2005)—and we intuitively know that there are boundaries to our exploitation. But defining these boundaries has been a challenge since Malthus first prophesied that nature would limit the human population (Malthus 1798). In 2009, Rockström and colleagues tried to quantify what the 6.8 billion (and counting) of us could continue to get away with, and what we couldn't (Rockström et al 2009). In selecting ten 'planetary boundaries', the authors contend that a sustainable human enterprise requires treating a number of environmental thresholds as points of no return. They suggest we breach these Rubicons at our own peril, and that we've already crossed three: biodiversity loss, atmospheric CO2, and disruption of the global nitrogen (N) cycle. As they clearly hoped, the very act of setting targets has provoked scientific inquiry about their accuracy, and about the value of hard targets in the first place (Schlesinger 2009). Such debate is a good thing. Despite recent emphasis on the science of human-ecosystem interactions, understanding of our planetary boundaries is still in its infancy, and controversy can speed scientific progress (Engelhardt and Caplan 1987). A few weeks ago in this journal, Carpenter and Bennett (2011) took aim at one of the more controversial boundaries in the Rockström analysis: that for human alteration of the global phosphorus (P) cycle. Rockström's group chose riverine P export as the key indicator, suggesting that humans should not exceed a value that could trigger widespread marine anoxic events—and asserting that we have not yet crossed this threshold. There are defensible reasons for a marine

  4. boundary dissipation

    Directory of Open Access Journals (Sweden)

    Mehmet Camurdan

    1998-01-01

    are coupled by appropriate trace operators. This overall model differs from those previously studied in the literature in that the elastic chamber floor is here more realistically modeled by a hyperbolic Kirchoff equation, rather than by a parabolic Euler-Bernoulli equation with Kelvin-Voight structural damping, as in past literature. Thus, the hyperbolic/parabolic coupled system of past literature is replaced here by a hyperbolic/hyperbolic coupled model. The main result of this paper is a uniform stabilization of the coupled PDE system by a (physically appealing boundary dissipation.

  5. The Atmospheric Boundary Layer

    Science.gov (United States)

    Garratt, J. R.

    1994-05-01

    A comprehensive and lucid account of the physics and dynamics of the lowest one to two kilometers of the Earth's atmosphere in direct contact with the Earth's surface, known as the atmospheric boundary layer (ABL). Dr. Garratt emphasizes the application of the ABL problems to numerical modeling of the climate, which makes this book unique among recent texts on the subject. He begins with a brief introduction to the ABL before leading to the development of mean and turbulence equations and the many scaling laws and theories that are the cornerstone of any serious ABL treatment. Modeling of the ABL is crucially dependent for its realism on the surface boundary conditions, so chapters four and five deal with aerodynamic and energy considerations, with attention given to both dry and wet land surfaces and the sea. The author next treats the structure of the clear-sky, thermally stratified ABL, including the convective and stable cases over homogeneous land, the marine ABL, and the internal boundary layer at the coastline. Chapter seven then extends this discussion to the cloudy ABL. This is particularly relevant to current research because the extensive stratocumulus regions over the subtropical oceans and stratus regions over the Arctic have been identified as key players in the climate system. In the final chapters, Dr. Garratt summarizes the book's material by discussing appropriate ABL and surface parameterization schemes in general circulation models of the atmosphere that are being used for climate stimulation.

  6. Soil and vegetation dynamics in a forest-savannah boundary in Southern Amazon state during the holocene, using 14C dating and stable carbon isotopes of soil organic matter

    International Nuclear Information System (INIS)

    Vidotto, Elaine; Pessenda, Luiz Carlos Ruiz; Ribeiro, Adauto de Souza; Bendassolli, Jose Albertino

    2005-01-01

    This work presents a comparative study between organic soil horizons formed in depressions, distant ca. 500 meters from each sampling site, in a forest/savannah boundary in the Southern Amazon Basin. The influence of the paleovegetation and soil dynamics, based on carbon isotope ( 12 C, 13 C, 14 C) data of soil organic matter (SOM) was evaluated. The soils were classified as Dystropept (Cambissolo) and were considered as clayey. The total organic carbon contents decreased from the surface to deeper parts of the soils profiles. At deeper parts of the soil profiles in the savannah site, between 100 cm and 30 cm, the δ 13 C values characterized the influence of C 4 plants (around -18,0 per mille). From about 20 cm to the surface the δ 13 C values characterized the mixture of C 3 and C 4 plants. The soil δ 13 C values in the forest site ranged from -25,0 per mille at deeper parts of the profile to -26,0 per mille in the surface, characterizing the dominance of C 3 plants in this location. 13 C and 14 C data from soil samples indicated a predominance of C 3 plants in the early Holocene. From ca. 7000 to 3000 years BP the influence of C 4 plants increased, characterizing a savannah expansion probably related to a drier climate in the region. Since 3000 years 14 C BP, the carbon isotope data suggest the forest expansion, probably due to a return to wetter climate. 14 C data in the 40-50 cm and 100 cm soil depth were contemporary, showing no difference on the soil organic matter deposition in the savannah and in the forest locations. (author)

  7. The effect of sleep on nocturnal urine output

    DEFF Research Database (Denmark)

    Kamperis, Konstantinos; Hagstrøm, Søren; Rittig, Søren

    2005-01-01

    sleep and the sequence was randomized. During these nights with sleep deprivation, participants were in lying position in a dimly lit room and physical activities, food and fluid intake were not allowed. Smoking was not allowed throughout the entire experimental protocol. Determinations of electrolytes...... sleep related physiological mechanisms into consideration. In the present study we report that acute sleep deprivation has a dramatic effect on the volume of nocturnal urine production in both genders although the effect is more pronounced in males. Natriuresis and kaliuresis were observed on nights...

  8. Nocturnal Activity of a Captive Aye-aye (Daubentonia madagascariensis)

    OpenAIRE

    IWANO, Taizo

    1991-01-01

    This report aims to clarify the nocturnal activity of the aye-aye (Daubentonia madagascariensis) under captive conditions to compare it with that under natural conditions. The aye-aye was nocuturnal and showed activity at any time at night. However, from 02:00 hrs until just prior to dawn, it often rested. It frequently returned to the nest throughout this period to take long rests of more than half an hour. The aye-aye's activities were classified into four categories: feeding, moving, resti...

  9. Neuroethology of ultrasonic hearing in nocturnal butterflies (Hedyloidea)

    DEFF Research Database (Denmark)

    Yack, Jayne E.; Kalko, Elisabeth K.V.; Surlykke, Annemarie

    2007-01-01

    Nocturnal Hedyloidea butterflies possess ultrasound-sensitive ears that mediate evasive flight maneuvers. Tympanal ear morphology, auditory physiology and behavioural responses to ultrasound are described for Macrosoma heliconiaria, and evidence for hearing is described for eight other hedylid...... species. The ear is formed by modifications of the cubital and subcostal veins at the forewing base, where the thin (1-3 m), ovoid (520 £ 220 )mpanal membrane occurs in a cavity. The ear is innervated by nerve IIN1c, with three chordotonal organs attaching to separate regions of the tympanal membrane...

  10. The Nocturnal Avian Migration Experiment Final Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Stepanian, P. M. [Univ. of Oklahoma, Norman, OK (United States); Horton, K. G. [Univ. of Oklahoma, Norman, OK (United States)

    2016-03-01

    Remote sensing techniques are playing a greater role in ornithology, and radar has proven a valuable tool for high resolution, long-term observations of airborne animals. The major disadvantage in radar remote sensing is the current inability to gain taxonomic information from these measurements. One solution is the incorporation of collocated acoustic monitoring that can provide recordings of species-specific nocturnal flight calls of migrating birds in flight. In addition, by taking multichannel recordings of these calls, the position of the calling bird can be calculated and linked to collocated radar measurements.

  11. Pattern of Primary Nocturnal Enuresis in Primary School Children ...

    African Journals Online (AJOL)

    Objectifs: Apprécier la prévalence de l'énurésie nocturne chez des enfants élèves à l'école primaire (âgés de 6 à 7 ans) dans la ville d'Assiut et d'apprécier ses caractères et ses facteurs de risque. Patients et Méthodes: Une étude randomisée incluant 1519 enfants a été réalisée dans 10 écoles primaires de la ville d'Assiut ...

  12. Association of Smoking, Sleep Apnea, and Plasma Alkalosis With Nocturnal Ventricular Arrhythmias in Men With Systolic Heart Failure

    Science.gov (United States)

    Shukla, Rakesh; Wexler, Laura

    2012-01-01

    Background: Excess sudden death due to ventricular tachyarrhythmias remains a major mode of mortality in patients with systolic heart failure. The aim of this study was to determine the association of nocturnal ventricular arrhythmias in patients with low ejection fraction heart failure. We incorporated a large number of known pathophysiologic triggers to identify potential targets for therapy to reduce the persistently high incidence of sudden death in this population despite contemporary treatment. Methods: Eighty-six ambulatory male patients with stable low (≤ 45%) ejection fraction heart failure underwent full-night attendant polysomnography and simultaneous Holter recordings. Patients were divided into groups according to the presence or absence of couplets (paired premature ventricular excitations) and ventricular tachycardia (VT) (at least three consecutive premature ventricular excitations) during sleep. Results: In multiple regression analysis, four variables (current smoking status, increased number of arousals, plasma alkalinity, and old age) were associated with VT and two variables (apnea-hypopnea index and low right ventricular ejection fraction) were associated with couplets during sleep. Conclusions: We speculate that cessation of smoking, effective treatment of sleep apnea, and plasma alkalosis could collectively decrease the incidence of nocturnal ventricular tachyarrhythmias and the consequent risk of sudden death, which remains high despite the use of β blockades. PMID:22172636

  13. Nocturnal hypoxia in ALS is related to cognitive dysfunction and can occur as clusters of desaturations.

    Directory of Open Access Journals (Sweden)

    Su-Yeon Park

    Full Text Available Amyotrophic lateral sclerosis (ALS is a neurodegenerative disease that leads to progressive weakness of the respiratory and limb muscles. Consequently, most patients with ALS exhibit progressive hypoventilation, which worsens during sleep. The aim of this study was to evaluate the relationship between nocturnal hypoxia and cognitive dysfunction and to assess the pattern of nocturnal hypoxia in patients with ALS.Twenty-five patients with definite or probable ALS underwent neuropsychologic testing, nocturnal pulse oximetry, and capnography. Patients were grouped according to the presence of nocturnal hypoxia (SpO2<95% for ≥10% of the night and their clinical characteristics and cognitive function were compared.Compared to patients without nocturnal hypoxia, those with nocturnal hypoxia (n = 10, 40% had poor memory retention (p = 0.039 and retrieval efficiency (p = 0.045. A cluster-of-desaturation pattern was identified in 7 patients (70% in the Hypoxia Group.These results suggest that nocturnal hypoxia can be related to cognitive dysfunction in ALS. In addition, a considerable number of patients with ALS may be exposed to repeated episodes of deoxygenation-reoxygenation (a cluster-of-desaturation pattern during sleep, which could be associated with the generation of reactive oxygen species. Further studies are required to define the exact causal relationships between these phenomena, the exact manifestations of nocturnal cluster-of-desaturation patterns, and the effect of clusters of desaturation on ALS progression.

  14. Capnography for assessing nocturnal hypoventilation and predicting compliance with subsequent noninvasive ventilation in patients with ALS.

    Directory of Open Access Journals (Sweden)

    Sung-Min Kim

    Full Text Available BACKGROUND: Patients with amyotrophic lateral sclerosis (ALS suffer from hypoventilation, which can easily worsen during sleep. This study evaluated the efficacy of capnography monitoring in patients with ALS for assessing nocturnal hypoventilation and predicting good compliance with subsequent noninvasive ventilation (NIV treatment. METHODS: Nocturnal monitoring and brief wake screening by capnography/pulse oximetry, functional scores, and other respiratory signs were assessed in 26 patients with ALS. Twenty-one of these patients were treated with NIV and had their treatment compliance evaluated. RESULTS: Nocturnal capnography values were reliable and strongly correlated with the patients' respiratory symptoms (R(2 = 0.211-0.305, p = 0.004-0.021. The duration of nocturnal hypercapnea obtained by capnography exhibited a significant predictive power for good compliance with subsequent NIV treatment, with an area-under-the-curve value of 0.846 (p = 0.018. In contrast, no significant predictive values for nocturnal pulse oximetry or functional scores for nocturnal hypoventilation were found. Brief waking supine capnography was also useful as a screening tool before routine nocturnal capnography monitoring. CONCLUSION: Capnography is an efficient tool for assessing nocturnal hypoventilation and predicting good compliance with subsequent NIV treatment of ALS patients, and may prove useful as an adjunctive tool for assessing the need for NIV treatment in these patients.

  15. Nocturnal eating predicts tooth loss among adults: results from the Danish MONICA study

    DEFF Research Database (Denmark)

    Lundgren, Jennifer D; Williams, Karen B; Heitmann, Berit L

    2010-01-01

    The relationship between nocturnal eating, such as that associated with night eating syndrome (NES), and oral health is unknown. This study sought to determine if nocturnal eating is related to tooth loss in a large, epidemiologic sample. Danes (N=2217; age range 30-60 years, M BMI [kg/m(2...

  16. The Effectiveness of Silodosin for Nocturnal Polyuria in Elderly Men With Benign Prostatic Hyperplasia: A Multicenter Study

    OpenAIRE

    Kim, Young Won; Park, Jinsung; Chung, Hong; Kim, Hong-Wook; Kim, Hyung Joon; Jung, Jae Hung; Kim, Won Tae

    2015-01-01

    Purpose: To investigate improvement in nocturia and nocturnal polyuria in nocturnal polyuria patients after silodosin administration by using a 3-day frequency volume chart. Methods: This was a prospective multicenter study. We enrolled nocturnal polyuria patients (nocturnal polyuria index [NPi]>0.33), aged ≥60 years, diagnosed with the 3-day frequency volume charts of patients with benign prostatic hyperplasia taking α-blockers. Of the 54 patients, 30 (55.6%) completed the study according to...

  17. Arousal in Nocturnal Consciousness: How Dream- and Sleep-Experiences May Inform Us of Poor Sleep Quality, Stress, and Psychopathology.

    Science.gov (United States)

    Soffer-Dudek, Nirit

    2017-01-01

    The term "sleep experiences," coined by Watson (2001), denotes an array of unusual nocturnal consciousness phenomena; for example, nightmares, vivid or recurrent dreams, hypnagogic hallucinations, dreams of falling or flying, confusional arousals, and lucid dreams. Excluding the latter, these experiences reflect a single factor of atypical oneiric cognitions ("general sleep experiences"). The current study is an opinionated mini-review on the associations of this factor-measured with the Iowa sleep experiences survey (ISES, Watson, 2001)-with psychopathological symptoms and stress. Findings support a strong relation between psychological distress and general sleep experiences. It is suggested that that they should be viewed as a sleep disturbance; they seem to represent involuntary intrusions of wakefulness into sleep, resulting in aroused sleep. These intrusions may stem from excessively thin boundaries between consciousness states (e.g., "transliminality"), or, conversely, they may follow an attempt at disconnecting mental elements (e.g., dissociation), which paradoxically results in a "rebound effect." The extent to which unusual dreaming is experienced as intrusive, rather than controlled, may explain why general sleep experiences are related to psychopathology, whereas lucid dreams are related to psychological resilience. In conclusion, the exploration of the interplay between psychopathology and sleep should be expanded from focusing almost exclusively on quantitative aspects (e.g., sleep efficiency, latency) to including qualitative conscious experiences which may reflect poor sleep quality. Taking into account nocturnal consciousness-including unusual dreaming and permeable sleep-wake boundaries-may unveil rich information on night-time emotional states and broaden our definition of poor sleep quality.

  18. Comparing the effects of nocturnal sleep and daytime napping on declarative memory consolidation.

    Directory of Open Access Journals (Sweden)

    June C Lo

    Full Text Available Nocturnal sleep and daytime napping facilitate memory consolidation for semantically related and unrelated word pairs. We contrasted forgetting of both kinds of materials across a 12-hour interval involving either nocturnal sleep or daytime wakefulness (experiment 1 and a 2-hour interval involving either daytime napping or wakefulness (experiment 2. Beneficial effects of post-learning nocturnal sleep and daytime napping were greater for unrelated word pairs (Cohen's d=0.71 and 0.68 than for related ones (Cohen's d=0.58 and 0.15. While the size of nocturnal sleep and daytime napping effects was similar for unrelated word pairs, for related pairs, the effect of nocturnal sleep was more prominent. Together, these findings suggest that sleep preferentially facilitates offline memory processing of materials that are more susceptible to forgetting.

  19. Comparing the effects of nocturnal sleep and daytime napping on declarative memory consolidation.

    Science.gov (United States)

    Lo, June C; Dijk, Derk-Jan; Groeger, John A

    2014-01-01

    Nocturnal sleep and daytime napping facilitate memory consolidation for semantically related and unrelated word pairs. We contrasted forgetting of both kinds of materials across a 12-hour interval involving either nocturnal sleep or daytime wakefulness (experiment 1) and a 2-hour interval involving either daytime napping or wakefulness (experiment 2). Beneficial effects of post-learning nocturnal sleep and daytime napping were greater for unrelated word pairs (Cohen's d=0.71 and 0.68) than for related ones (Cohen's d=0.58 and 0.15). While the size of nocturnal sleep and daytime napping effects was similar for unrelated word pairs, for related pairs, the effect of nocturnal sleep was more prominent. Together, these findings suggest that sleep preferentially facilitates offline memory processing of materials that are more susceptible to forgetting.

  20. Artificial light pollution increases nocturnal vigilance in peahens

    Directory of Open Access Journals (Sweden)

    Jessica L. Yorzinski

    2015-08-01

    Full Text Available Artificial light pollution is drastically changing the sensory environments of animals. Even though many animals are now living in these changed environments, the effect light pollution has on animal behavior is poorly understood. We investigated the effect of light pollution on nocturnal vigilance in peahens (Pavo cristatus. Captive peahens were exposed to either artificial lighting or natural lighting at night. We employed a novel method to record their vigilance behavior by attaching accelerometers to their heads and continuously monitoring their large head movements. We found that light pollution significantly increases nocturnal vigilance in peahens. Furthermore, the birds faced a trade-off between vigilance and sleep at night: peahens that were more vigilant spent less time sleeping. Given the choice, peahens preferred to roost away from high levels of artificial lighting but showed no preference for roosting without artificial lighting or with low levels of artificial lighting. Our study demonstrates that light pollution can have a substantial impact on animal behavior that can potentially result in fitness consequences.

  1. Relationship between sleep stages and nocturnal trapezius muscle activity.

    Science.gov (United States)

    Müller, Christian; Nicoletti, Corinne; Omlin, Sarah; Brink, Mark; Läubli, Thomas

    2015-06-01

    Former studies reported a relationship between increased nocturnal low level trapezius muscle activity and neck or shoulder pain but it has not been explored whether trapezius muscle relaxation is related to sleep stages. The goal of the present study was to investigate whether trapezius muscle activity is related to different sleep stages, as measured by polysomnography. Twenty one healthy subjects were measured on four consecutive nights in their homes, whereas the first night served as adaptation night. The measurements included full polysomnography (electroencephalography (EEG), electrooculography (EOG), electromyography (EMG) and electrocardiography (ECG)), as well as surface EMG of the m. trapezius descendens of the dominant arm. Periods with detectable EMG activity of the trapezius muscle lasted on average 1.5% of the length of the nights and only in four nights it lasted longer than 5% of sleeping time. Neither rest time nor the length of periods with higher activity levels of the trapezius muscle did significantly differ between sleep stages. We found no evidence that nocturnal trapezius muscle activity is markedly moderated by the different sleep stages. Thus the results support that EMG measurements of trapezius muscle activity in healthy subjects can be carried out without concurrent polysomnographic recordings. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Nocturnal polyuria and saluresis in renal allograft recipients.

    Science.gov (United States)

    Chan, M K; Varghese, Z; Fernando, O N; Moorhead, J F

    1980-01-01

    The evolution of nocturnal polyuria and saluresis in renal allograft recipients was studied by comparing the day to night (D:N) ratios of urine volume and sodium excretion in 15 patients who had undergone transplantation less than one year previously (recent-transplant group) with those in 11 patients who had undergone transplantation at least one year previously. Eleven patients with chronic renal failure and 12 normal subjects served as controls. Patients in the recent-transplant group had significantly lower D:N ratios of urine volume and sodium excretion than the patients who had undergone transplantation at least a year before, while the ratios in this last group did not differ significantly from those in the normal subjects. Nocturnal polyuria and saluresis gradually subsided in five patients studied for three months. Chronic renal failure and uraemic autonomic neuropathy were unlikely causes of the nocturia. The patients in the recent-transplant group had significantly lower D:N ratios of urine volume than the controls with chronic renal failure, and the mean Valsalva ratio in eight of them was not significantly different from that in the normal subjects. An undue sensitivity of renal allografts to postural influences was proposed. PMID:6986946

  3. Artificial light pollution increases nocturnal vigilance in peahens.

    Science.gov (United States)

    Yorzinski, Jessica L; Chisholm, Sarah; Byerley, Sydney D; Coy, Jeanee R; Aziz, Aisyah; Wolf, Jamie A; Gnerlich, Amanda C

    2015-01-01

    Artificial light pollution is drastically changing the sensory environments of animals. Even though many animals are now living in these changed environments, the effect light pollution has on animal behavior is poorly understood. We investigated the effect of light pollution on nocturnal vigilance in peahens (Pavo cristatus). Captive peahens were exposed to either artificial lighting or natural lighting at night. We employed a novel method to record their vigilance behavior by attaching accelerometers to their heads and continuously monitoring their large head movements. We found that light pollution significantly increases nocturnal vigilance in peahens. Furthermore, the birds faced a trade-off between vigilance and sleep at night: peahens that were more vigilant spent less time sleeping. Given the choice, peahens preferred to roost away from high levels of artificial lighting but showed no preference for roosting without artificial lighting or with low levels of artificial lighting. Our study demonstrates that light pollution can have a substantial impact on animal behavior that can potentially result in fitness consequences.

  4. Stable Isotope Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Tissue samples (skin, bone, blood, muscle) are analyzed for stable carbon, stable nitrogen, and stable sulfur analysis. Many samples are used in their entirety for...

  5. Solution of moving boundary problems with implicit boundary condition

    International Nuclear Information System (INIS)

    Moyano, E.A.

    1990-01-01

    An algorithm that solves numerically a model for studying one dimensional moving boundary problems, with implicit boundary condition, is described. Landau's transformation is used, in order to work with a fixed number of nodes at each instant. Then, it is necessary to deal with a parabolic partial differential equation, whose diffusive and convective terms have variable coefficients. The partial differential equation is implicitly discretized, using Laasonen's scheme, always stable, instead of employing Crank-Nicholson sheme, as it has been done by Ferris and Hill. Fixed time and space steps (Δt, Δξ) are used, and the iteration is made with variable positions of the interface, i.e. varying δs until a boundary condition is satisfied. The model has the same features of the oxygen diffusion in absorbing tissue. It would be capable of estimating time variant radiation treatments of cancerous tumors. (Author) [es

  6. Primary nocturnal enuresis in children. Background and treatment.

    Science.gov (United States)

    Wille, S

    1994-01-01

    The aim of the present studies was to investigate background factors and treatment in children with monosymptomatic primary nocturnal enuresis. The study material comprised enuretics, former enuretics and controls from the municipal community of Falkenberg on the west coast of Sweden. Whenever possible all investigations were made with the children staying in their own home environment. Different background factors have been suspected as being causative: sleep disturbances, behavioural or psychological disturbances, small bladder capacity, increased night diuresis and an insufficient production of the antidiuretic hormone during sleep. These factors have been investigated in these studies. The treatment of enuresis has been dominated by the alarm and antidiuretic treatment with DDAVP. Primary nocturnal monosymptomatic enuresis is a common problem in childhood. In this study the prevalence among 392 seven year old children was 7.3%. A prior history of enuresis was found in 65% of families of the enuretics compared to 25% in controls. The enuretic children showed no statistically significant differences in behavioural or psychological problems compared to non-enuretic children. Enuretic children were described as heavy sleepers by their parents and a wake-up test performed at home showed that they were statistically significantly harder to arouse than the controls. Children with nocturnal enuresis, former enuretics and controls did not differ in social or behavioural traits in an interview study. No signs of symptom substitution was found when enuresis was resolved. Enuretic children had a normal bladder capacity and no statistically significant difference was found compared to controls and former enuretics. The enuretic children showed a normal calcium-creatinine quota in the urine. Former enuretic children showed a significantly enhanced calcium/creatinine quota compared to enuretics and controls. Enuretic children had a statistically significant lower morning

  7. Getting a good night sleep? The importance of recognizing and treating nocturnal hypokinesia in Parkinson's disease.

    Science.gov (United States)

    Bhidayasiri, Roongroj; Trenkwalder, Claudia

    2018-01-05

    When Parkinson's disease (PD) patients are asked about the quality of their sleep, their answers are dominated by difficulties associated with impaired mobility in bed, medically referred to as nocturnal hypokinesia. Nocturnal hypokinesia is symptomatic from the mid-stage of the disease, affecting up to 70% of PD patients, and contributes to poor sleep quality, and increased carer burden. Here we explore four areas of nocturnal hypokinesia that are relevant to clinical practice, namely: manifestations and definition; clinical assessment and objective monitoring; etiologies and contributing factors; and evidence-based therapeutic approaches. In addition, we provide an operational definition of what constitutes nocturnal hypokinesia and outline different methods of assessment, ranging from clinical interviews and rating scales to objective night-time monitoring with inertial sensors. Optimal management of nocturnal hypokinesia in PD begins with recognizing its manifestation by inquiring about cardinal symptoms and contributing factors from, not only patients, but also carers, followed by formal assessment, and the application of individualized evidence-based treatment. Night-time dopaminergic treatment is the primary therapy; however, careful clinical judgment is required to balance the benefits with the potential adverse events related to nocturnal dopaminergic stimulation. Future studies are needed to explore the practicality of home-based objective assessment of nocturnal hypokinesia, new therapeutic options not limited to dopaminergic medications, and non-pharmacologic approaches, including training on compensatory strategies and bedroom adaptations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. 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.

  9. 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.

  10. Late postoperative nocturnal episodic hypoxaemia and associated sleep pattern

    DEFF Research Database (Denmark)

    Rosenberg, J; Wildschiødtz, G; Pedersen, M H

    1994-01-01

    significantly after surgery (P REM) sleep decreased significantly on the first night after operation (P REM sleep (rebound) on the second, third or both nights after operation compared with the preoperative night. Slow wave sleep...... was depressed significantly on the first two nights after operation (P REM sleep-associated hypoxaemic episodes for individual patients increased about three-fold on the second and third nights after operation compared with the night before operation (P sleep...... pattern is disturbed severely with early depression of REM and slow wave sleep and with rebound of REM sleep on the second and third nights. Postoperative rebound of REM sleep may contribute to the development of sleep disordered breathing and nocturnal episodic hypoxaemia....

  11. Differential approach to treatment of primary nocturnal enuresis in children

    Directory of Open Access Journals (Sweden)

    Nesterenko O.V.

    2011-09-01

    Full Text Available The aim of the work is to develop an algorithm of differentiated therapy in children with PNE. 234 children aged 5-15 years were studied. Results of treatment of children with primary nocturnal enuresis using the traditional therapeutic scheme and the algorithm of differential therapy based on identification of individual pathology were analyzed. The best clinical effect (recovery— in 73,1%, improvement— in 19,4% of cases was obtained in children undergone the complex of recommended measures: psychological consultation, rational and family psychotherapy, medication correction, physical and physiotherapy, alarm-monitoring; the complex was used differentially, i.e. depending on the identified pathology. In conclusion the article stated that individual treatment program with the obligatory inclusion of alarm-control for child with PNE should be selected after performing the recommended set of diagnostic measures

  12. Autism in siblings with autosomal dominant nocturnal frontal lobe epilepsy.

    Science.gov (United States)

    Miyajima, Tomoko; Kumada, Tomohiro; Saito, Keiko; Fujii, Tatsuya

    2013-02-01

    In 1999, Hirose et al. reported a Japanese family with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) associated with a neuronal nicotinic acetylcholine receptor α4 subunit mutation (S252L). We followed the siblings of this family, and found that the elder brother had Asperger's disorder without mental retardation (MR) and the younger brother had autistic disorder with profound MR. The clinical epileptic features of the siblings were very similar, and both had deficits in socialization, but their cognitive development differed markedly. It thus seems that epilepsy is the direct phenotype of the S252L mutation, whereas other various factors modulate the cognitive and social development. No patients with ADNFLE have previously been reported to have autism spectrum disorder or profound MR. Copyright © 2012 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  13. Acute tubular necrosis in a patient with paroxysmal nocturnal hemoglobinuria

    Directory of Open Access Journals (Sweden)

    Eranga S Wijewickrama

    2013-01-01

    Full Text Available Acute renal failure (ARF is a well-recognized complication of paroxysmal nocturnal hemoglobinuria (PNH. The predominant mechanism is intravascular hemolysis resulting in massive hemoglobinuria ARF. We report a case of acute tubular necrosis (ATN developed in the absence of overwhelming evidence of intravascular hemolysis in a 21-year-old man with anemia, who was eventually diagnosed to have PNH. The patient presented with rapidly deteriorating renal functions in the background of iron deficiency anemia, which was attributed to reflux esophagitis. There was no clinical or laboratory evidence of intravascular hemolysis. Renal biopsy revealed ATN with deposition of hemosiderin in the proximal tubular epithelial cells. Diagnosis of PNH was confirmed with a positive Ham′s test and flow cytometry. Our case emphasizes the need to consider ATN as a possible cause for ARF in patients suspected to have PNH even in the absence of overwhelming evidence of intravascular hemolysis.

  14. Paroxysmal nocturnal hemoglobinuria: a case report of MR, CT findings

    International Nuclear Information System (INIS)

    Yang, Ik; Chung, Soo Young; Park, Hai Jung; Lee Yul; Chun, Rho Won; Noh, Jung Woo

    1995-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired disease involving multiple hematopoietic cell lines. Characteristics of PNH are intrinsic hemolytic anemia, iron deficiency anemia and venous thrombosis. We report a case of PNH with characterostoc MR and CT findings. The signal intensity of renal cortex was lower than that of medulla on both T1-and T2-weighted MR imaging. On T2 weighted MR images, the liver showed very low signal intensity but the signal intensity of the spleen was normal. On precontrast CT the attenuation of renal cortex was higher than that of renal medulla and the attenuation of liver was higher than that of the spleen. These findings of MR imaging and CT were the result from the deposition of hemosiderin in the cells of proximal convoluted tubules and transfusional hemosiderosis of liver

  15. Nocturnal activity of nesting shrubland and grassland passerines: Chapter 9

    Science.gov (United States)

    Slay, Christy M.; Ellison, Kevin S.; Ribic, Christine; Smith, Kimberly G.; Schmitz, Carolyn M.

    2013-01-01

    Nocturnal activity of nesting passerines is largely undocumented in field situations. We used video recordings to quantify sleep patterns of four shrubland and three grassland bird species during the nestling period. All species exhibited “back sleep” (bill tucked under scapular feathers); individuals woke frequently for vigils of their surroundings. Sleep-bout duration varied from 6 minutes (grasshopper sparrow) to 28 minutes (blue-winged warbler, field sparrow). Duration on nest varied from 6.4 hours (field sparrow) to 8.8 hours (indigo bunting). Adults woke 20–30 minutes before sunrise. First morning absence from the nest was short; nestlings were fed within 12 minutes of a parent’s departure. Further research is needed to understand energetic costs of sleep and behavioral adaptations to environmental pressures.

  16. Observations and models of simple nocturnal slope flows

    International Nuclear Information System (INIS)

    Doran, J.C.; Horst, J.W.

    1983-01-01

    Measurements of simple nocturnal slope winds were taken on Rattlesnake Mountain, a nearly ideal two-dimensional ridge. Tower and tethered balloon instrumentation allowed the determination of the wind and temperature characteristics of the katabatic layer as well as the ambient conditions. Two cases were chosen for study; these were marked by well-defined surface-based temperature inversions and a low-level maximum in the downslope wind component. The downslope development of the slope flow could be determined from the tower measurements, and showed a progressive strenghtening of the katabatic layer. Hydraulic models developed by Manins and Sawford (1979a) and Briggs (1981) gave useful estimates of drainage layer depths, but were not otherwise applicable. A simple numerical model that relates the eddy diffusivity to the local turbulent kinetic energy was found to give good agreement with the observed wind and temperature profiles of the slope flows

  17. A cutoff value based on analysis of a reference population decreases overestimation of the prevalence of nocturnal polyuria.

    Science.gov (United States)

    van Haarst, Ernst P; Bosch, J L H Ruud

    2012-09-01

    We sought criteria for nocturnal polyuria in asymptomatic, nonurological adults of all ages by reporting reference values of the ratio of daytime and nighttime urine volumes, and finding nocturia predictors. Data from a database of frequency-volume charts from a reference population of 894 nonurological, asymptomatic volunteers of all age groups were analyzed. The nocturnal polyuria index and the nocturia index were calculated and factors influencing these values were determined by multivariate analysis. The nocturnal polyuria index had wide variation but a normal distribution with a mean ± SD of 30% ± 12%. The 95th percentile of the values was 53%. Above this cutoff a patient had nocturnal polyuria. This value contrasts with the International Continence Society definition of 33% but agrees with several other reports. On multivariate regression analysis with the nocturnal polyuria index as the dependent variable sleeping time, maximum voided volume and age were the covariates. However, the increase in the nocturnal polyuria index by age was small. Excluding polyuria and nocturia from analysis did not alter the results in a relevant way. The nocturnal voiding frequency depended on sleeping time and maximum voided volume but most of all on the nocturia index. The prevalence of nocturnal polyuria is overestimated. We suggest a new cutoff value for the nocturnal polyuria index, that is nocturnal polyuria exists when the nocturnal polyuria index exceeds 53%. The nocturia index is the best predictor of nocturia. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  18. Decreased Nocturnal Movements in Patients with Facioscapulohumeral Muscular Dystrophy

    Science.gov (United States)

    Marca, Giacomo Della; Frusciante, Roberto; Dittoni, Serena; Vollono, Catello; Losurdo, Anna; Testani, Elisa; Scarano, Emanuele; Colicchio, Salvatore; Iannaccone, Elisabetta; Tonali, Pietro A.; Ricci, Enzo

    2010-01-01

    Study Objectives: Reduced mobility during sleep characterizes a variety of movement disorders and neuromuscular diseases. Facioscapulohumeral muscular dystrophy (FSHD) is the third most common form of muscular dystrophy in the general population, and people with FSHD have poor sleep quality. The aims of the present study were to evaluate nocturnal motor activity in patients with FSHD by means of videopolysomnography and to verify whether activity was associated with modifications in sleep structure. Methods: We enrolled 32 adult patients affected by genetically confirmed FSHD (18 women and 14 men, mean age 45.1 ± 13.4 years) and 32 matched control subjects, (18 women and 14 men, mean age 45.5 ± 11.4 years). Major body movements (MBM) were scored in videopolygraphic recordings in accordance with established criteria. An MBM index was calculated (number of MBM per hour of sleep). Results: The FSHD group showed a decrease in the MBM index (FSHD: 1.2 ± 1.1; control subjects: 2.3 ± 1.2, analysis of variance F = 13.672; p = 0.008). The sleep pattern of patients with FSHD, as compared with that of controls, was characterized by longer sleep latencies, shorter sleep durations, an increased percentage of wake during sleep, and a decreased percentage of rapid eye movement sleep. In the patient group, the MBM index was inversely correlated with severity of disease (Spearman test: r30 = −0.387; p Marca GD; Frusciante R; Dittoni S; Vollono C; Losurdo A; Testani E; Scarano E; Colicchio S; Iannaccone E; Tonali PA; Ricci E. Decreased nocturnal movements in patients with facioscapulohumeral muscular dystrophy. J Clin Sleep Med 2010;6(3):276-280. PMID:20572422

  19. Simvastatin-induced nocturnal leg pain disappears with pravastatin substitution

    Directory of Open Access Journals (Sweden)

    Stojaković Nataša

    2013-01-01

    Full Text Available Introduction. Statins have similar side effects that do not always occur at the same rate among the various statins. We present a case of simvastatin-induced muscle toxicity that disappeared when pravastatin was substituted for the original drug. Case Outline. A 74-year-old male, a nonsmoker, complained of severe nocturnal leg cramps. The patient also complained that similar painful cramping occurred when he walked rapidly or jogged. Because some components of his lipid panel exceeded the ‘desirable’ range, and as he had a history of myocardial infarction, his family physician prescribed simvastatin (40 mg/day. The patient had taken this medication for the past eight years. The painful nocturnal episodes started two years ago and affected either one or the other leg. Four months ago we discontinued his simvastatin and prescribed pravastatin (80 mg/day. At a follow-up visit six weeks later, the patient reported that his leg pains at night and the pain experienced after brisk walking had disappeared. Four months after the substitution of pravastatin for simvastatin, the patient reported that his complete lack of symptoms had continued. Conclusion. These painful muscle cramps were probably caused by an inadequate vascular supply to the calf and foot muscles. Perhaps a combination of advanced age and atherosclerotic changes created a predisposition for the simvastatin-induced leg cramps. Pravastatin differs from simvastatin in several ways. It is not metabolized by cytochrome P450 (CYP 3A4 oxidases, and thus is not influenced by CYP 3A4 inhibitors like simvastatin. Also, simvastatin is associated with single-nucleotide polymorphisms located within the SLCO1B1 gene on the chromosome 12 and established myopathy, while pravastatin lacks this association. These differences may contribute to increased tolerance to pravastatin in this particular case.

  20. Simvastatin-lnduced nocturnal leg pain disappears with pravastatin substitution.

    Science.gov (United States)

    Stojaković, Natasa; Igić, Rajko

    2013-01-01

    Statins have similar side effects that do not always occur at the same rate among the various statins. We present a case of simvastatin-induced muscle toxicity that disappeared when pravastatin was substituted for the original drug. A 74-year-old male, a nonsmoker, complained of severe nocturnal leg cramps. The patient also complained that similar painful cramping occurred when he walked rapidly or jogged. Because some components of his lipid panel exceeded the'desirable' range, and as he had a history of myocardial infarction, his family physician prescribed simvastatin (40 mg/day). The patient had taken this medication for the past eight years. The painful nocturnal episodes started two years ago and affected either one or the other leg. Four months ago we discontinued his simvastatin and prescribed pravastatin (80 mg/day). At a follow-up visit six weeks later, the patient reported that his leg pains at night and the pain experienced after brisk walking had disappeared. Four months after the substitution of pravastatin for simvastatin, the patient reported that his complete lack of symptoms had continued. These painful muscle cramps were probably caused by an inadequate vascular supply to the calf and foot muscles. Perhaps a combination of advanced age and atherosclerotic changes created a predisposition for the simvastatin-induced leg cramps. Pravastatin differs from simvastatin in several ways.l It is not metabolized by cytochrome P450 (CYP) 3A4 oxidases, and thus is not influenced by CYP 3A4 inhibitors like simvastatin. Also, simvastatin is associated with single-nucleotide polymorphisms located within the SLCO1B1 gene on the chromosome 12 and established myopathy, while pravastatin lacks this association. These differences may contribute to increased tolerance to pravastatin in this particular case.

  1. Nocturnal insects use optic flow for flight control.

    Science.gov (United States)

    Baird, Emily; Kreiss, Eva; Wcislo, William; Warrant, Eric; Dacke, Marie

    2011-08-23

    To avoid collisions when navigating through cluttered environments, flying insects must control their flight so that their sensory systems have time to detect obstacles and avoid them. To do this, day-active insects rely primarily on the pattern of apparent motion generated on the retina during flight (optic flow). However, many flying insects are active at night, when obtaining reliable visual information for flight control presents much more of a challenge. To assess whether nocturnal flying insects also rely on optic flow cues to control flight in dim light, we recorded flights of the nocturnal neotropical sweat bee, Megalopta genalis, flying along an experimental tunnel when: (i) the visual texture on each wall generated strong horizontal (front-to-back) optic flow cues, (ii) the texture on only one wall generated these cues, and (iii) horizontal optic flow cues were removed from both walls. We find that Megalopta increase their groundspeed when horizontal motion cues in the tunnel are reduced (conditions (ii) and (iii)). However, differences in the amount of horizontal optic flow on each wall of the tunnel (condition (ii)) do not affect the centred position of the bee within the flight tunnel. To better understand the behavioural response of Megalopta, we repeated the experiments on day-active bumble-bees (Bombus terrestris). Overall, our findings demonstrate that despite the limitations imposed by dim light, Megalopta-like their day-active relatives-rely heavily on vision to control flight, but that they use visual cues in a different manner from diurnal insects. This journal is © 2011 The Royal Society

  2. Technology for Boundaries

    DEFF Research Database (Denmark)

    Bødker, Susanne; Kristensen, Jannie Friis; Nielsen, Christina

    2003-01-01

    .After analysing the history and the current boundary work, the paper will propose new technological support for boundary work. In particular the paper will suggest means of supporting boundaries when these are productive and for changing boundaries when this seems more appropriate. In total, flexible technologies......This paper presents a study of an organisation, which is undergoing a process transforming organisational and technological boundaries. In particular, we shall look at three kinds of boundaries: the work to maintain and change the boundary between the organisation and its customers; boundaries...... seem a core issue when dealing with technology for boundaries....

  3. Stable convergence and stable limit theorems

    CERN Document Server

    Häusler, Erich

    2015-01-01

    The authors present a concise but complete exposition of the mathematical theory of stable convergence and give various applications in different areas of probability theory and mathematical statistics to illustrate the usefulness of this concept. Stable convergence holds in many limit theorems of probability theory and statistics – such as the classical central limit theorem – which are usually formulated in terms of convergence in distribution. Originated by Alfred Rényi, the notion of stable convergence is stronger than the classical weak convergence of probability measures. A variety of methods is described which can be used to establish this stronger stable convergence in many limit theorems which were originally formulated only in terms of weak convergence. Naturally, these stronger limit theorems have new and stronger consequences which should not be missed by neglecting the notion of stable convergence. The presentation will be accessible to researchers and advanced students at the master's level...

  4. Networked Thermodynamic Boundary Layer Profiling with AERIs during the PECAN Field Campaign

    Science.gov (United States)

    Gero, P. J.; Turner, D. D.; Hackel, D.; Phillips, C.; Smith, N.; Wagner, T.

    2015-12-01

    The Plains Elevated Convection at Night (PECAN) campaign was a large-scale field experiment in the Great Plains region of the U.S. that was conducted in June-July 2015. Nocturnal storms provide the majority of the precipitation in the Great Plains, yet the initiation and evolution of nocturnal convection is not understood to the same level as daytime surface-based convection, and thus provides significant challenges for operational weather forecasters. PECAN's objectives were to study elevated nocturnal convection initiation and the lifecycle of nocturnal convection. Specific research areas that were studied were the evolution of mesoscale convective systems, the structure and evolution of nocturnal low-level jets, atmospheric bores, and elevated convection initiation. A broad range of fixed and mobile observing systems were deployed by several agencies and organizations in a domain centered around Kansas. The Atmospheric Emitted Radiance Interferometer (AERI) is a ground-based instrument that measures downwelling infrared radiance from the atmosphere. AERI observations can be used to obtain vertical profiles of tropospheric temperature and water vapor in the lowest 3 km of the troposphere, as well as measurements of the concentration of various trace gases and microphysical and optical properties of clouds and aerosols. A network of eight AERIs was deployed in the domain during PECAN, with six at fixed sites and two in mobile facilities. One of the goals of the campaign was a demonstration of the use of real-time high-temporal-resolution boundary layer profiles from the network of AERIs for characterizing the mesoscale environment and its evolution during the weather events sampled during PECAN. If successful, a future network could be implemented across CONUS and thermodynamic profiles in the boundary layer data assimilated to help improve numerical weather prediction. We present an overview of the AERI deployments, a summary of the technique used to retrieve

  5. Arousal in Nocturnal Consciousness: How Dream- and Sleep-Experiences May Inform Us of Poor Sleep Quality, Stress, and Psychopathology

    Science.gov (United States)

    Soffer-Dudek, Nirit

    2017-01-01

    The term “sleep experiences,” coined by Watson (2001), denotes an array of unusual nocturnal consciousness phenomena; for example, nightmares, vivid or recurrent dreams, hypnagogic hallucinations, dreams of falling or flying, confusional arousals, and lucid dreams. Excluding the latter, these experiences reflect a single factor of atypical oneiric cognitions (“general sleep experiences”). The current study is an opinionated mini-review on the associations of this factor—measured with the Iowa sleep experiences survey (ISES, Watson, 2001)—with psychopathological symptoms and stress. Findings support a strong relation between psychological distress and general sleep experiences. It is suggested that that they should be viewed as a sleep disturbance; they seem to represent involuntary intrusions of wakefulness into sleep, resulting in aroused sleep. These intrusions may stem from excessively thin boundaries between consciousness states (e.g., “transliminality”), or, conversely, they may follow an attempt at disconnecting mental elements (e.g., dissociation), which paradoxically results in a “rebound effect.” The extent to which unusual dreaming is experienced as intrusive, rather than controlled, may explain why general sleep experiences are related to psychopathology, whereas lucid dreams are related to psychological resilience. In conclusion, the exploration of the interplay between psychopathology and sleep should be expanded from focusing almost exclusively on quantitative aspects (e.g., sleep efficiency, latency) to including qualitative conscious experiences which may reflect poor sleep quality. Taking into account nocturnal consciousness—including unusual dreaming and permeable sleep-wake boundaries—may unveil rich information on night-time emotional states and broaden our definition of poor sleep quality. PMID:28539902

  6. Arousal in Nocturnal Consciousness: How Dream- and Sleep-Experiences May Inform Us of Poor Sleep Quality, Stress, and Psychopathology

    Directory of Open Access Journals (Sweden)

    Nirit Soffer-Dudek

    2017-05-01

    Full Text Available The term “sleep experiences,” coined by Watson (2001, denotes an array of unusual nocturnal consciousness phenomena; for example, nightmares, vivid or recurrent dreams, hypnagogic hallucinations, dreams of falling or flying, confusional arousals, and lucid dreams. Excluding the latter, these experiences reflect a single factor of atypical oneiric cognitions (“general sleep experiences”. The current study is an opinionated mini-review on the associations of this factor—measured with the Iowa sleep experiences survey (ISES, Watson, 2001—with psychopathological symptoms and stress. Findings support a strong relation between psychological distress and general sleep experiences. It is suggested that that they should be viewed as a sleep disturbance; they seem to represent involuntary intrusions of wakefulness into sleep, resulting in aroused sleep. These intrusions may stem from excessively thin boundaries between consciousness states (e.g., “transliminality”, or, conversely, they may follow an attempt at disconnecting mental elements (e.g., dissociation, which paradoxically results in a “rebound effect.” The extent to which unusual dreaming is experienced as intrusive, rather than controlled, may explain why general sleep experiences are related to psychopathology, whereas lucid dreams are related to psychological resilience. In conclusion, the exploration of the interplay between psychopathology and sleep should be expanded from focusing almost exclusively on quantitative aspects (e.g., sleep efficiency, latency to including qualitative conscious experiences which may reflect poor sleep quality. Taking into account nocturnal consciousness—including unusual dreaming and permeable sleep-wake boundaries—may unveil rich information on night-time emotional states and broaden our definition of poor sleep quality.

  7. Nutritional Status in Nocturnal Hemodialysis Patients : A Systematic Review with Meta-Analysis

    NARCIS (Netherlands)

    Ipema, Karin J. R.; Struijk, Simone; van der Velden, Annet; Westerhuis, Ralf; van der Schans, Cees P.; Gaillard, Carlo A. J. M.; Krijnen, Wim P.; Franssen, Casper F. M.

    2016-01-01

    Background Hemodialysis patients experience an elevated risk of malnutrition associated with increased morbidity and mortality. Nocturnal hemodialysis (NHD) results in more effective removal of waste products and fluids. Therefore, diet and fluid restrictions are less restricted in NHD patients.

  8. Lack of nocturnal blood pressure fall in elderly bedridden hypertensive patients with cerebrovascular disease.

    Science.gov (United States)

    Sasaki, Masato; Ando, Hitoshi; Fujimura, Akio

    2012-02-01

    To prevent recurrence of cerebrovascular disease (CVD), adequate control of blood pressure (BP) is extremely important for the treatment of hypertensive CVD patients. As absence of the nocturnal fall of BP by the expected 10-20% from daytime levels is reported to exaggerate target organ injury, 24-h ambulatory blood pressure monitoring (ABPM) was conducted, especially to obtain data during nighttime sleep. Forty-eight elderly bedridden chronic phase CVD hypertensive patients (assessed 1-3 mo after CVD accident) participated. As a group, nocturnal BP was higher than diurnal BP, whereas nocturnal pulse rate was lower than diurnal pulse rate. The nocturnal BP fall was blunted in most (∼90%) of the patients. These results suggest that to perform a rational drug treatment, it is essential to do 24-h ABPM before initiation of antihypertensive therapy in elderly bedridden hypertensive CVD patients.

  9. Glaucomatous Optic Neuropathy Associated with Nocturnal Dip in Blood Pressure: Findings from the Maracaibo Aging Study.

    Science.gov (United States)

    Melgarejo, Jesús D; Lee, Joseph H; Petitto, Michele; Yépez, Juan B; Murati, Felipe A; Jin, Zhezhen; Chávez, Carlos A; Pirela, Rosa V; Calmón, Gustavo E; Lee, Winston; Johnson, Matthew P; Mena, Luis J; Al-Aswad, Lama A; Terwilliger, Joseph D; Allikmets, Rando; Maestre, Gladys E; De Moraes, C Gustavo

    2018-01-05

    To determine which nocturnal blood pressure (BP) parameters (low levels or extreme dipper status) are associated with an increased risk of glaucomatous damage in Hispanics. Observational cross-sectional study. A subset (n = 93) of the participants from the Maracaibo Aging Study (MAS) who met the study eligibility criteria were included. These participants, who were at least 40 years of age, had measurements for optical tomography coherence, visual field (VF) tests, 24-hour BP, office BP, and intraocular pressure 20% compared with daytime BP) were significant risk factors for glaucomatous damage (odds ratio, 19.78 and 5.55, respectively). In this population, the link between nocturnal BP and GON is determined by extreme dipping effects rather than low nocturnal BP levels alone. Further studies considering extreme decreases in nocturnal BP in individuals at high risk of glaucoma are warranted. Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  10. Effect of the complement inhibitor eculizumab on thromboembolism in patients with paroxysmal nocturnal hemoglobinuria.

    NARCIS (Netherlands)

    Hillmen, P.; Muus, P.; Duhrsen, U.; Risitano, A.M.; Schubert, J.; Luzzatto, L.; Schrezenmeier, H.; Szer, J.; Brodsky, R.A.; Hill, A.; Socie, G.; Bessler, M.; Rollins, S.A.; Bell, L.; Rother, R.P.; Young, N.S.

    2007-01-01

    Hemolysis and hemoglobinemia contribute to serious clinical sequelae in hemolytic disorders. In paroxysmal nocturnal hemoglobinuria (PNH) patients, hemolysis can contribute to thromboembolism (TE), the most feared complication in PNH, and the leading cause of disease-related deaths. We evaluated

  11. Nocturnal Polyuria in Older Women with Urge Urinary Incontinence: Role of Sleep Quality, Time in Bed and Medications Used.

    Science.gov (United States)

    Tyagi, Shachi; Perera, Subashan; Clarkson, Becky D; Tadic, Stasa D; Resnick, Neil M

    2017-03-01

    Nocturia is common and bothersome in older adults, especially those who are also incontinent. Since nocturnal polyuria is a major contributor, we examined factors associated with nocturnal polyuria in this population to identify those possibly amenable to intervention. We analyzed baseline data from 2 previously completed studies of urge urinary incontinence. The studies involved 284 women (mean age ± SD 72.9 ± 7.9 years) who also completed 3-day voiding diaries. Participants with a nocturnal polyuria index greater than 33% were categorized as having nocturnal polyuria (nocturnal polyuria index = nocturnal urinary volume per 24-hour urine volume). Associations between nocturnal polyuria and various demographic, clinical and sleep related parameters were determined. Overall 55% of the participants had nocturnal polyuria. Multivariable regression analysis revealed that age, body mass index, use of angiotensin converting enzyme inhibitor/angiotensin receptor blocker, time spent in bed and duration of first uninterrupted sleep were independent correlates of nocturnal polyuria. Participants with a larger nocturnal excretion reported a shorter duration of uninterrupted sleep before first awakening to void and worse sleep quality despite spending similar time in bed. Body mass index, use of angiotensin converting enzyme inhibitor/angiotensin receptor blockers, time in bed and duration of uninterrupted sleep before first awakening to void are independently associated with nocturnal polyuria in older women with urge urinary incontinence, and are potentially modifiable. These findings also confirm the association between sleep and nocturnal polyuria. Further studies should explore whether interventions to reduce nocturnal polyuria and/or increase the duration of uninterrupted sleep before first awakening to void would help to improve sleep quality in this population and thereby reduce or eliminate the need for sedative hypnotics. Copyright © 2017 American Urological

  12. Visual reliability and information rate in the retina of a nocturnal bee.

    Science.gov (United States)

    Frederiksen, Rikard; Wcislo, William T; Warrant, Eric J

    2008-03-11

    Nocturnal animals relying on vision typically have eyes that are optically and morphologically adapted for both increased sensitivity and greater information capacity in dim light. Here, we investigate whether adaptations for increased sensitivity also are found in their photoreceptors by using closely related and fast-flying nocturnal and diurnal bees as model animals. The nocturnal bee Megalopta genalis is capable of foraging and homing by using visually discriminated landmarks at starlight intensities. Megalopta's near relative, Lasioglossum leucozonium, performs these tasks only in bright sunshine. By recording intracellular responses to Gaussian white-noise stimuli, we show that photoreceptors in Megalopta actually code less information at most light levels than those in Lasioglossum. However, as in several other nocturnal arthropods, Megalopta's photoreceptors possess a much greater gain of transduction, indicating that nocturnal photoreceptors trade information capacity for sensitivity. By sacrificing photoreceptor signal-to-noise ratio and information capacity in dim light for an increased gain and, thus, an increased sensitivity, this strategy can benefit nocturnal insects that use neural summation to improve visual reliability at night.

  13. Nocturnal oxygen saturation profiles of healthy term infants.

    Science.gov (United States)

    Terrill, Philip Ian; Dakin, Carolyn; Hughes, Ian; Yuill, Maggie; Parsley, Chloe

    2015-01-01

    Pulse oximetry is used extensively in hospital and home settings to measure arterial oxygen saturation (SpO2). Interpretation of the trend and range of SpO2 values observed in infants is currently limited by a lack of reference ranges using current devices, and may be augmented by development of cumulative frequency (CF) reference-curves. This study aims to provide reference oxygen saturation values from a prospective longitudinal cohort of healthy infants. Prospective longitudinal cohort study. Sleep-laboratory. 34 healthy term infants were enrolled, and studied at 2 weeks, 3, 6, 12 and 24 months of age (N=30, 25, 27, 26, 20, respectively). Full overnight polysomnography, including 2 s averaging pulse oximetry (Masimo Radical). Summary SpO2 statistics (mean, median, 5th and 10th percentiles) and SpO2 CF plots were calculated for each recording. CF reference-curves were then generated for each study age. Analyses were repeated with sleep-state stratifications and inclusion of manual artefact removal. Median nocturnal SpO2 values ranged between 98% and 99% over the first 2 years of life and the CF reference-curves shift right by 1% between 2 weeks and 3 months. CF reference-curves did not change with manual artefact removal during sleep and did not vary between rapid eye movement (REM) and non-REM sleep. Manual artefact removal did significantly change summary statistics and CF reference-curves during wake. SpO2 CF curves provide an intuitive visual tool for evaluating whether an individual's nocturnal SpO2 distribution falls within the range of healthy age-matched infants, thereby complementing summary statistics in the interpretation of extended oximetry recordings in infants. 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.

  14. stableGP

    Data.gov (United States)

    National Aeronautics and Space Administration — The code in the stableGP package implements Gaussian process calculations using efficient and numerically stable algorithms. Description of the algorithms is in the...

  15. Angina Pectoris (Stable Angina)

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Angina Pectoris (Stable Angina) Updated:Aug 21,2017 You may have heard the term “angina pectoris” or “stable angina” in your doctor’s office, ...

  16. Longitudinal vortices in a transitioning boundary layer

    International Nuclear Information System (INIS)

    Anders, J.B.; Backwelder, R.F.

    1980-01-01

    Naturally occurring spanwise variations of the streamwise velocity component, characteristic of longitudinal vortices embedded in a transitioning boundary layer were explored using hot-wire anemometers. A vibrating ribbon introduced stable or unstable Tollmien-Schlichting waves into the laminar boundary layer. These damped or growing disturbances always developed a strong three-dimensional pattern even though no spanwise perturbations were artificially induced. Changing the radius of the leading edge and other modifications to the flat plate, wind tunnel and boundary layer did not alter the spanwise wavelength of the vortices. (orig.)

  17. Cerebral stroke in a teenage girl with paroxysmal nocturnal hemoglobinuria

    Directory of Open Access Journals (Sweden)

    Francesco Gervasi

    2017-06-01

    Full Text Available We report a case of paroxysmal nocturnal hemoglobinuria (PNH in a 14 year-old girl presenting a cerebral arterial thrombosis. The initial diagnosis was carential anemia due to menarche following identification of slight macrocytic anemia, leucopenia and mild thrombocytopenia at routine blood analysis. The child was eventually referred to a children’s hospital after the onset of progressive fatigue, anorexia and paleness. Severe anemia (hemoglobin 6 g/dL with negative Coombs test, mild leucopenia (white blood cells 4.9×109/L and thrombocytopenia (platelets 97×109/L and high values of lactate dehydrogenase (2855 U/L were identified; a packed red cells transfusion was administered. Her condition worsened and she subsequently presented complete right hemiplegia, aphasia and coma; magnetic resonance imaging revealed a massive ischemic lesion. A diagnosis of PNH was eventually made following high sensitivity flow cytometry, which identified a PNH clone (CD66b negative equal to 93.7% of granulocytes. Fast recovery from neurologic and hematological problems occurred in response to anticoagulant therapy and intravenous therapy with eculizumab. We are convinced that PNH should be included in the differential diagnosis of children presenting with cytopenia.

  18. Sensory system plasticity in a visually specialized, nocturnal spider.

    Science.gov (United States)

    Stafstrom, Jay A; Michalik, Peter; Hebets, Eileen A

    2017-04-21

    The interplay between an animal's environmental niche and its behavior can influence the evolutionary form and function of its sensory systems. While intraspecific variation in sensory systems has been documented across distant taxa, fewer studies have investigated how changes in behavior might relate to plasticity in sensory systems across developmental time. To investigate the relationships among behavior, peripheral sensory structures, and central processing regions in the brain, we take advantage of a dramatic within-species shift of behavior in a nocturnal, net-casting spider (Deinopis spinosa), where males cease visually-mediated foraging upon maturation. We compared eye diameters and brain region volumes across sex and life stage, the latter through micro-computed X-ray tomography. We show that mature males possess altered peripheral visual morphology when compared to their juvenile counterparts, as well as juvenile and mature females. Matching peripheral sensory structure modifications, we uncovered differences in relative investment in both lower-order and higher-order processing regions in the brain responsible for visual processing. Our study provides evidence for sensory system plasticity when individuals dramatically change behavior across life stages, uncovering new avenues of inquiry focusing on altered reliance of specific sensory information when entering a new behavioral niche.

  19. Phenytoin-induced isolated chronic, nocturnal dry cough

    Directory of Open Access Journals (Sweden)

    Fábio A. Nascimento

    2016-01-01

    Full Text Available We report a 72-year-old man with a four-year history of dyscognitive seizures (with occasional secondary generalization who developed isolated, nocturnal dry cough immediately after being started on PO phenytoin. The cough was not accompanied by any other symptom or sign as his physical exam was completely normal. Further investigation with chest CT and spirometry was unremarkable. This symptom persisted for six months and did not resolve until we weaned him off of phenytoin. According to the Naranjo Adverse Drug Reaction Probability Scale, his cough was classified as being probably (score +6 related to the use of this antiepileptic drug. To our knowledge, there has been only one study that reported phenytoin-triggered cough. It described a postoperative patient who developed cough and bronchospasm after receiving IV phenytoin. By reporting our case and discussing the literature on this specific topic, we have essentially two goals. First, we intend to remind clinicians that isolated persistent cough can be an adverse reaction to phenytoin. Second, we hope to encourage further studies that will be able to elucidate the association presented herein.

  20. Polarized light use in the nocturnal bull ant, Myrmecia midas.

    Science.gov (United States)

    Freas, Cody A; Narendra, Ajay; Lemesle, Corentin; Cheng, Ken

    2017-08-01

    Solitary foraging ants have a navigational toolkit, which includes the use of both terrestrial and celestial visual cues, allowing individuals to successfully pilot between food sources and their nest. One such celestial cue is the polarization pattern in the overhead sky. Here, we explore the use of polarized light during outbound and inbound journeys and with different home vectors in the nocturnal bull ant, Myrmecia midas . We tested foragers on both portions of the foraging trip by rotating the overhead polarization pattern by ±45°. Both outbound and inbound foragers responded to the polarized light change, but the extent to which they responded to the rotation varied. Outbound ants, both close to and further from the nest, compensated for the change in the overhead e-vector by about half of the manipulation, suggesting that outbound ants choose a compromise heading between the celestial and terrestrial compass cues. However, ants returning home compensated for the change in the e-vector by about half of the manipulation when the remaining home vector was short (1-2 m) and by more than half of the manipulation when the remaining vector was long (more than 4 m). We report these findings and discuss why weighting on polarization cues change in different contexts.

  1. Compass cues used by a nocturnal bull ant, Myrmecia midas.

    Science.gov (United States)

    Freas, Cody A; Narendra, Ajay; Cheng, Ken

    2017-05-01

    Ants use both terrestrial landmarks and celestial cues to navigate to and from their nest location. These cues persist even as light levels drop during the twilight/night. Here, we determined the compass cues used by a nocturnal bull ant, Myrmecia midas , in which the majority of individuals begin foraging during the evening twilight period. Myrmecia midas foragers with vectors of ≤5   m when displaced to unfamiliar locations did not follow the home vector, but instead showed random heading directions. Foragers with larger home vectors (≥10   m) oriented towards the fictive nest, indicating a possible increase in cue strength with vector length. When the ants were displaced locally to create a conflict between the home direction indicated by the path integrator and terrestrial landmarks, foragers oriented using landmark information exclusively and ignored any accumulated home vector regardless of vector length. When the visual landmarks at the local displacement site were blocked, foragers were unable to orient to the nest direction and their heading directions were randomly distributed. Myrmecia midas ants typically nest at the base of the tree and some individuals forage on the same tree. Foragers collected on the nest tree during evening twilight were unable to orient towards the nest after small lateral displacements away from the nest. This suggests the possibility of high tree fidelity and an inability to extrapolate landmark compass cues from information collected on the tree and at the nest site to close displacement sites. © 2017. Published by The Company of Biologists Ltd.

  2. Investigation of nocturnal oviposition by necrophilous flies in central Texas.

    Science.gov (United States)

    Baldridge, Robert S; Wallace, Susan G; Kirkpatrick, Ryan

    2006-01-01

    The need to accurately estimate the postmortem interval (PMI) has prompted research into factors affecting fly oviposition (i.e., oviposition and/or larviposition) on a corpse. Research efforts have focused on whether or not diurnally active flies oviposit during nighttime hours. This study reports that nocturnal oviposition (defined as occurring between 2100-0600 h CDST (Central Daylight Savings Time)) did not occur on freshly killed white rats or mice, on beef (fresh or aged up to 48 h), on freshly thawed pigs, nor, usually, on thawed pigs that were aged for up to 48 h. Limited oviposition did occur between 2100 and 2120 h on one bloated pig at a lighted rural site. Necrophilous flies were present and active at lighted and dark sites (urban and rural) before and immediately after sunset, but fly activity on the bait ceased within 50 min postsunset and did not resume until after 0600 h. These observations support other studies reporting that diurnally active flies do not oviposit during the nighttime.

  3. A Moessbauer study of hemoglobin in paroxysmal nocturnal hemoglobinuria

    International Nuclear Information System (INIS)

    Zamorano-Ulloa, R.; Yee-Madeira, H.; Flores-Llamas, H.; Perez-Ramirez, J.G.

    1991-01-01

    The 57 Fe Moessbauer spectra of concentrated hemoglobin (Hb) of normal subjects and six patients with Paroxysmal Nocturnal Hemoglobinuria (PNH) were studied at 300deg K and 77 K. PNH is a very rate autoimmune hematological disease. The possibility of structural alterations of Hb induced by, or as part of the altered PNH-red cell membrane was the objective of this study. The Moessbauer parameters of the Hb of the normal subjects, both at 300 K and at 77 K, are identical to values previously reported. The PNH-Hb spectra show clear differences. They are wider and more asymmetric. At 77 K, an extra doublet grows in with an isomer shift of 0.425 mm/sec. and a quadrupolar splitting of 1.951 mm/sec. The other two doublets have δ's and ΔQ's slightly, but significantly, different from the corresponding values for normal Hb. These results are rationalized in terms of a population of Hb molecules with structures varying very slightly in a narrow range. The spread in structures manifests itself in a wider and more asymmetric Moessbauer spectrum. (orig.)

  4. Slow nocturnal home hemodialysis (SNHHD)--one year later.

    Science.gov (United States)

    Ouwendyk, M; Pierratos, A; Francoeur, R; Wallace, L; Sit, W; Vas, S

    1996-01-01

    High costs and overcrowding of dialysis centres are leading to a global crisis in health care provision. We are developing slow nocturnal home hemodialysis (SNHHD) in which patients dialyze for eight to 10 hours during sleep five to seven nights per week. Vascular access is by means of the Cook silastic jugular catheter. Special precautions are taken to prevent accidental disconnection and air embolism. Dialysis functions are remotely monitored on computer via a modem by trained staff. Five patients have completed five to seven weeks of training and have been successfully performing SNHHD single-handedly (three out of five patients live alone) for 14, 14, 11, 10 and four months respectively. All have discontinued their phosphate binders and increased dietary phosphate intake. Compared with conventional hemodialysis (CHD) results, average pre-dialysis urea and creatinine levels are remarkably reduced to 9.6 mmol/l and 486 umol/l respectively. The average cumulative weekly Kt/V for CHD is 5.0 as compared to 7.7 while on SNHHD. Four out of five patients report sleeping soundly and experience greatly increased energy and stamina. Their days are entirely free. Repeated in-situ re-use of the dialyzer and blood lines will reduce the patient's work and make SNHHD a very inexpensive modality. SNHHD appears to be a widely applicable treatment with many advantages to both the patient and the health care system.

  5. Vertical ozone characteristics in urban boundary layer in Beijing.

    Science.gov (United States)

    Ma, Zhiqiang; Xu, Honghui; Meng, Wei; Zhang, Xiaoling; Xu, Jing; Liu, Quan; Wang, Yuesi

    2013-07-01

    Vertical ozone and meteorological parameters were measured by tethered balloon in the boundary layer in the summer of 2009 in Beijing, China. A total of 77 tethersonde soundings were taken during the 27-day campaign. The surface ozone concentrations measured by ozonesondes and TEI 49C showed good agreement, albeit with temporal difference between the two instruments. Two case studies of nocturnal secondary ozone maxima are discussed in detail. The development of the low-level jet played a critical role leading to the observed ozone peak concentrations in nocturnal boundary layer (NBL). The maximum of surface ozone was 161.7 ppbv during the campaign, which could be attributed to abundant precursors storage near surface layer at nighttime. Vertical distribution of ozone was also measured utilizing conventional continuous analyzers on 325-m meteorological observation tower. The results showed the NBL height was between 47 and 280 m, which were consistent with the balloon data. Southerly air flow could bring ozone-rich air to Beijing, and the ozone concentrations exceeded the China's hourly ozone standard (approximately 100 ppb) above 600 m for more than 12 h.

  6. Exploring Scintillometry in the Stable Atmospheric Surface Layer

    NARCIS (Netherlands)

    Hartogensis, O.K.

    2006-01-01

    The main objective of this thesis is to investigate observation methods of heat and momentum exchange and key variables that characterise turbulence in the atmospheric stable surface layer (SSL), a layer defined as the lower part of the stable boundary layer (SBL) where surface fluxes do not change

  7. Rigid supersymmetry with boundaries

    Energy Technology Data Exchange (ETDEWEB)

    Belyaev, D.V. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Van Nieuwenhuizen, P. [State Univ. of New York, Stony Brook, NY (United States). C.N. Yang Inst. for Theoretical Physics

    2008-01-15

    We construct rigidly supersymmetric bulk-plus-boundary actions, both in x-space and in superspace. For each standard supersymmetric bulk action a minimal supersymmetric bulk-plus-boundary action follows from an extended F- or D-term formula. Additional separately supersymmetric boundary actions can be systematically constructed using co-dimension one multiplets (boundary superfields). We also discuss the orbit of boundary conditions which follow from the Euler-Lagrange variational principle. (orig.)

  8. The inland boundary layer at low latitudes

    Science.gov (United States)

    Garratt, J. R.

    1985-08-01

    Observations from the Koorin boundary-layer experiment in Australia (latitude 16 °S) were analysed in a study of the nocturnal jet development. For geostrophic winds in the range 10 20 m s-1, ageostrophic wind magnitudes of 5 10m s-1 were common above the surface layer near sunset, with cross-isobar flow angles of about 40 °. The jet that then developed by midnight was probably the result of these large ageostrophic winds, strong surface cooling and favourable baroclinity and sloping terrain. The analysis is supported by numerical model calculations with special emphasis on the role of long-wave radiative cooling on turbulent decay. Decay is rapid in the presence of radiation, although there is little influence on stress divergence levels. Evidence of sea-breeze influences on the jet evolution, and on features of deeply penetrating sea breezes in general, will be presented and discussed in part 2 of this study (submitted to Boundary-Layer Meteorol.).

  9. Effects of the glucagon-like peptide-1receptor agonist liraglutide on 24-h ambulatory blood pressure in patients with type 2 diabetes and stable coronary artery disease

    DEFF Research Database (Denmark)

    Kumarathurai, Preman; Anholm, Christian; Fabricius-Bjerre, Andreas

    2017-01-01

    -one patients with type 2 diabetes and stable coronary artery disease were randomized to receive liraglutide or placebo to a backbone therapy of metformin in this double-blind, placebo-controlled 12 along with 12 weeks crossover study. Ambulatory blood pressure monitoring (ABPM) was performed at the start...... or the nocturnal BP dipping. Conclusions: We could not demonstrate any BP-lowering effect of liraglutide when using 24-h ABPM. Liraglutide exhibited diurnal variation in the effect on BP without affecting the BP variability or nocturnal BP dipping....

  10. Paroxysmal nocturnal hemoglobinuria and telomere length predicts response to immunosuppressive therapy in pediatric aplastic anemia.

    Science.gov (United States)

    Narita, Atsushi; Muramatsu, Hideki; Sekiya, Yuko; Okuno, Yusuke; Sakaguchi, Hirotoshi; Nishio, Nobuhiro; Yoshida, Nao; Wang, Xinan; Xu, Yinyan; Kawashima, Nozomu; Doisaki, Sayoko; Hama, Asahito; Takahashi, Yoshiyuki; Kudo, Kazuko; Moritake, Hiroshi; Kobayashi, Masao; Kobayashi, Ryoji; Ito, Etsuro; Yabe, Hiromasa; Ohga, Shouichi; Ohara, Akira; Kojima, Seiji

    2015-12-01

    Acquired aplastic anemia is an immune-mediated disease characterized by severe defects in stem cell number resulting in hypocellular marrow and peripheral blood cytopenias. Minor paroxysmal nocturnal hemoglobinuria populations and a short telomere length were identified as predictive biomarkers of immunosuppressive therapy responsiveness in aplastic anemia. We enrolled 113 aplastic anemia patients (63 boys and 50 girls) in this study to evaluate their response to immunosuppressive therapy. The paroxysmal nocturnal hemoglobinuria populations and telomere length were detected by flow cytometry. Forty-seven patients (42%) carried a minor paroxysmal nocturnal hemoglobinuria population. The median telomere length of aplastic anemia patients was -0.99 standard deviation (SD) (range -4.01-+3.01 SD). Overall, 60 patients (53%) responded to immunosuppressive therapy after six months. Multivariate logistic regression analysis identified the absence of a paroxysmal nocturnal hemoglobinuria population and a shorter telomere length as independent unfavorable predictors of immunosuppressive therapy response at six months. The cohort was stratified into a group of poor prognosis (paroxysmal nocturnal hemoglobinuria negative and shorter telomere length; 37 patients) and good prognosis (paroxysmal nocturnal hemoglobinuria positive and/or longer telomere length; 76 patients), respectively. The response rates of the poor prognosis and good prognosis groups at six months were 19% and 70%, respectively (P<0.001). The combined absence of a minor paroxysmal nocturnal hemoglobinuria population and a short telomere length is an efficient predictor of poor immunosuppressive therapy response, which should be considered while deciding treatment options: immunosuppressive therapy or first-line hematopoietic stem cell transplantation. The trial was registered in www.umin.ac.jp with number UMIN000017972. Copyright© Ferrata Storti Foundation.

  11. Survival with Three-Times Weekly In-Center Nocturnal Versus Conventional Hemodialysis

    Science.gov (United States)

    Xu, Jianglin; Suri, Rita S.; Nesrallah, Gihad; Lindsay, Robert; Garg, Amit X.; Lester, Keith; Ofsthun, Norma; Lazarus, Michael; Hakim, Raymond M.

    2012-01-01

    Whether the duration of hemodialysis treatments improves outcomes remains controversial. Here, we evaluated survival and clinical changes associated with converting from conventional hemodialysis (mean=3.75 h/treatment) to in-center nocturnal hemodialysis (mean=7.85 h/treatment). All 959 consecutive patients who initiated nocturnal hemodialysis for the first time in 77 Fresenius Medical Care facilities during 2006 and 2007 were eligible. We used Cox models to compare risk for mortality during 2 years of follow-up in a 1:3 propensity score–matched cohort of 746 nocturnal and 2062 control patients on conventional hemodialysis. Two-year mortality was 19% among nocturnal hemodialysis patients compared with 27% among conventional patients. Nocturnal hemodialysis associated with a 25% reduction in the risk for death after adjustment for age, body mass index, and dialysis vintage (hazard ratio=0.75, 95% confidence interval=0.61–0.91, P=0.004). With respect to clinical features, interdialytic weight gain, albumin, hemoglobin, dialysis dose, and calcium increased on nocturnal therapy, whereas postdialysis weight, predialysis systolic blood pressure, ultrafiltration rate, phosphorus, and white blood cell count declined (all P<0.001). In summary, notwithstanding the possibility of residual selection bias, conversion to treatment with nocturnal hemodialysis associates with favorable clinical features, laboratory biomarkers, and improved survival compared with propensity score–matched controls. The potential impact of extended treatment time on clinical outcomes while maintaining a three times per week hemodialysis schedule requires evaluation in future clinical trials. PMID:22362905

  12. Anatomical specializations for nocturnality in a critically endangered parrot, the Kakapo (Strigops habroptilus.

    Directory of Open Access Journals (Sweden)

    Jeremy R Corfield

    Full Text Available The shift from a diurnal to nocturnal lifestyle in vertebrates is generally associated with either enhanced visual sensitivity or a decreased reliance on vision. Within birds, most studies have focused on differences in the visual system across all birds with respect to nocturnality-diurnality. The critically endangered Kakapo (Strigops habroptilus, a parrot endemic to New Zealand, is an example of a species that has evolved a nocturnal lifestyle in an otherwise diurnal lineage, but nothing is known about its' visual system. Here, we provide a detailed morphological analysis of the orbits, brain, eye, and retina of the Kakapo and comparisons with other birds. Morphometric analyses revealed that the Kakapo's orbits are significantly more convergent than other parrots, suggesting an increased binocular overlap in the visual field. The Kakapo exhibits an eye shape that is consistent with other nocturnal birds, including owls and nightjars, but is also within the range of the diurnal parrots. With respect to the brain, the Kakapo has a significantly smaller optic nerve and tectofugal visual pathway. Specifically, the optic tectum, nucleus rotundus and entopallium were significantly reduced in relative size compared to other parrots. There was no apparent reduction to the thalamofugal visual pathway. Finally, the retinal morphology of the Kakapo is similar to that of both diurnal and nocturnal birds, suggesting a retina that is specialised for a crepuscular niche. Overall, this suggests that the Kakapo has enhanced light sensitivity, poor visual acuity and a larger binocular field than other parrots. We conclude that the Kakapo possesses a visual system unlike that of either strictly nocturnal or diurnal birds and therefore does not adhere to the traditional view of the evolution of nocturnality in birds.

  13. Diurnal and Nocturnal Pollination of Marginatocereus marginatus (Pachycereeae: Cactaceae) in Central Mexico

    Science.gov (United States)

    DAR, SALEEM; ARIZMENDI, Ma. del CORO; VALIENTE-BANUET, ALFONSO

    2006-01-01

    • Background and Aims Chiropterophillous and ornithophillous characteristics can form part of a single reproductive strategy in plants that have flowers with diurnal and nocturnal anthesis. This broader pollination strategy can ensure seed set when pollinators are scarce or unpredictable. This appears to be true of hummingbirds, which presumably pollinate Marginatocereus marginatus, a columnar cactus with red nocturnal and diurnal flowers growing as part of dense bat-pollinated columnar cacti forests in arid regions of central Mexico. The aim of this study was to study the floral biology of M. marginatus, and evaluate the effectiveness of nocturnal vs. diurnal pollinators and the contribution of each pollinator group to overall plant fitness. • Methods Individual flower buds were marked and followed to evaluate flower phenology and anthesis time. Flowers and nectar production were measured. An exclusion experiment was conducted to measure the relative contribution of nocturnal and diurnal pollinators to seed set. • Key Results Marginatocereus marginatus has red hermaphroditic flowers with nocturnal and diurnal anthesis. The plant cannot produce seeds by selfing and was pollinated during the day by hummingbirds and during the night by bats, demonstrating that both pollinator groups were important for plant reproduction. Strong pollen limitation was found in the absence of one of the pollinator guilds. • Conclusions Marginatocereus marginatus has an open pollination system in which both diurnal and nocturnal pollinators are needed to set seeds. This represents a fail-safe pollination system that can ensure both pollination, in a situation of low abundance of one of the pollinator groups (hummingbirds), and high competition for nocturnal pollinators with other columnar cacti that bloom synchronously with M. marginatus in the Tehuacan Valley, Mexico. PMID:16394025

  14. Sleep Apnea and Circadian Extracellular Fluid Change as Independent Factors for Nocturnal Polyuria.

    Science.gov (United States)

    Niimi, Aya; Suzuki, Motofumi; Yamaguchi, Yasuhiro; Ishii, Masaki; Fujimura, Tetsuya; Nakagawa, Tohru; Fukuhara, Hiroshi; Kume, Haruki; Igawa, Yasuhiko; Akishita, Masahiro; Homma, Yukio

    2016-10-01

    We investigated the relationships among nocturnal polyuria, sleep apnea and body fluid volume to elucidate the pathophysiology of nocturia in sleep apnea syndrome. We enrolled 104 consecutive patients who underwent polysomnography for suspected sleep apnea syndrome. Self-assessed symptom questionnaires were administered to evaluate sleep disorder and lower urinary tract symptoms, including nocturia. Voiding frequency and voided volume were recorded using a 24-hour frequency-volume chart. Body fluid composition was estimated in the morning and at night using bioelectric impedance analysis. Frequency-volume chart data were analyzed in 22 patients after continuous positive airway pressure therapy. Patients with nocturnal polyuria showed a higher apnea-hypopnea index (33.9 vs 24.2, p = 0.03) and a larger circadian change in extracellular fluid adjusted to lean body mass (0.22 vs -0.19, p = 0.019) than those without nocturnal polyuria. These relations were more evident in patients 65 years old or older than in those 64 years or younger. A multivariate linear regression model showed an independent relationship of nocturnal polyuria with the apnea-hypopnea index and the circadian change in extracellular fluid adjusted to lean body mass (p = 0.0012 and 0.022, respectively). Continuous positive airway pressure therapy significantly improved nocturnal polyuria and nocturia only in patients with nocturnal polyuria. This study identified sleep apnea and the circadian change in extracellular fluid as independent factors for nocturnal polyuria. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  15. Prevalence of Nocturnal Enuresis and Its Associated Factors in Primary School and Preschool Children of Khorramabad in 2013

    Directory of Open Access Journals (Sweden)

    Katayoun Bakhtiar

    2014-01-01

    Full Text Available Background. Nocturnal enuresis refers to an inability to control urination during sleep. This study aimed to determine the prevalence of nocturnal enuresis and its associated factors in children in the city of Khorramabad. Materials and Methods. In this descriptive-analytic, cross-sectional study, 710 male and female children were divided into two groups with equal numbers. The samples were selected from the schools of Khorramabad using the multistage cluster and stratified random sampling methods based on the diagnostic criteria of DSM-IV. The data was analyzed using the logistic regression. Results. The results showed that 8% of the children had nocturnal enuresis, including 5.2% of primary nocturnal enuresis and 2.8% of secondary nocturnal enuresis. The prevalence of nocturnal enuresis in the boys (10.7% was higher compared with that in the girls (5.4% (P=0.009. There were statistically significant relationships between nocturnal enuresis and history of nocturnal enuresis in siblings (P=0.023, respiratory infections (P=0.036, deep sleep (P=0.007, corporal punishment at school (P=0.036, anal itching (P=0.043, and history of seizures (P=0.043. Conclusion. This study showed that the prevalence of nocturnal enuresis in the boys was higher compared with that in the girls.

  16. Prevalence of nocturnal enuresis and its associated factors in primary school and preschool children of khorramabad in 2013.

    Science.gov (United States)

    Bakhtiar, Katayoun; Pournia, Yadollah; Ebrahimzadeh, Farzad; Farhadi, Ali; Shafizadeh, Fathollah; Hosseinabadi, Reza

    2014-01-01

    Background. Nocturnal enuresis refers to an inability to control urination during sleep. This study aimed to determine the prevalence of nocturnal enuresis and its associated factors in children in the city of Khorramabad. Materials and Methods. In this descriptive-analytic, cross-sectional study, 710 male and female children were divided into two groups with equal numbers. The samples were selected from the schools of Khorramabad using the multistage cluster and stratified random sampling methods based on the diagnostic criteria of DSM-IV. The data was analyzed using the logistic regression. Results. The results showed that 8% of the children had nocturnal enuresis, including 5.2% of primary nocturnal enuresis and 2.8% of secondary nocturnal enuresis. The prevalence of nocturnal enuresis in the boys (10.7%) was higher compared with that in the girls (5.4%) (P = 0.009). There were statistically significant relationships between nocturnal enuresis and history of nocturnal enuresis in siblings (P = 0.023), respiratory infections (P = 0.036), deep sleep (P = 0.007), corporal punishment at school (P = 0.036), anal itching (P = 0.043), and history of seizures (P = 0.043). Conclusion. This study showed that the prevalence of nocturnal enuresis in the boys was higher compared with that in the girls.

  17. Paroxysmal nocturnal haemoglobinuria at Oslo University Hospital 2000-2010.

    Science.gov (United States)

    Nissen-Meyer, Lise Sofie H; Tjønnfjord, Geir E; Golebiowska, Elzbieta; Kjeldsen-Kragh, Jens; Akkök, Çiğdem Akalın

    2015-06-16

    Paroxysmal nocturnal haemoglobinuria (PNH) is a rare haematological disease characterised by chronic haemolysis, pancytopenia and venous thrombosis. The condition is attributable to a lack of control of complement attack on erythrocytes, thrombocytes and leukocytes, and can be diagnosed by means of flow cytometry. In this quality assurance study, we have reviewed information from the medical records of all patients tested for PNH using flow cytometry at our laboratory over a ten-year period. In the period 2000-2010 a total of 28 patients were tested for PNH using flow cytometry at the Department of Immunology and Transfusion Medicine, Oslo University Hospital. We have reviewed the results of these examinations retrospectively together with information from medical records and transfusion data for the patients concerned. Flow cytometry identified 22 patients with PNH: four with classic disease and 18 with PNH secondary to another bone marrow disease. Five patients had atypical thrombosis. Seventeen patients received antithymocyte globulin or drug treatment; of these, six recovered from their bone marrow disease, while six died and five had a need for long-term transfusion. Five patients with life-threatening bone marrow disease underwent allogeneic stem cell transplantation, three of whom died. Six of 22 patients received eculizumab; the need for transfusion has been reduced or eliminated in three patients treated with eculizumab over a longer period. Flow cytometry identified PNH in a majority of patients from whom we obtained samples. Most patients had a PNH clone secondary to bone marrow failure. Atypical thrombosis should be borne in mind as an indication for the test. Treatment with eculizumab is relevant for selected patients with PNH.

  18. Ocellar adaptations for dim light vision in a nocturnal bee.

    Science.gov (United States)

    Berry, Richard P; Wcislo, William T; Warrant, Eric J

    2011-04-15

    Growing evidence indicates that insect ocelli are strongly adapted to meet the specific functional requirements in the environment in which that insect lives. We investigated how the ocelli of the nocturnal bee Megalopta genalis are adapted to life in the dim understory of a tropical rainforest. Using a combination of light microscopy and three-dimensional reconstruction, we found that the retinae contain bar-shaped rhabdoms loosely arranged in a radial pattern around multi-layered lenses, and that both lenses and retinae form complex non-spherical shapes reminiscent of those described in other ocelli. Intracellular electrophysiology revealed that the photoreceptors have high absolute sensitivity, but that the threshold location varied widely between 10(9) and 10(11) photons cm(-2) s(-1). Higher sensitivity and greater visual reliability may be obtained at the expense of temporal resolution: the corner frequencies of dark-adapted ocellar photoreceptors were just 4-11 Hz. Spectral sensitivity profiles consistently peaked at 500 nm. Unlike the ocelli of other flying insects, we did not detect UV-sensitive visual pigments in M. genalis, which may be attributable to a scarcity of UV photons under the rainforest canopy at night. In contrast to earlier predictions based on anatomy, the photoreceptors are not sensitive to the e-vector of polarised light. Megalopta genalis ocellar photoreceptors possess a number of unusual properties, including inherently high response variability and the ability to produce spike-like potentials. These properties bear similarities to photoreceptors in the compound eye of the cockroach, and we suggest that the two insects share physiological characteristics optimised for vision in dim light.

  19. Stable States of Biological Organisms

    Science.gov (United States)

    Yukalov, V. I.; Sornette, D.; Yukalova, E. P.; Henry, J.-Y.; Cobb, J. P.

    2009-04-01

    A novel model of biological organisms is advanced, treating an organism as a self-consistent system subject to a pathogen flux. The principal novelty of the model is that it describes not some parts, but a biological organism as a whole. The organism is modeled by a five-dimensional dynamical system. The organism homeostasis is described by the evolution equations for five interacting components: healthy cells, ill cells, innate immune cells, specific immune cells, and pathogens. The stability analysis demonstrates that, in a wide domain of the parameter space, the system exhibits robust structural stability. There always exist four stable stationary solutions characterizing four qualitatively differing states of the organism: alive state, boundary state, critical state, and dead state.

  20. Microalbuminuria in patients with non-insulin-dependent diabetes mellitus relates to nocturnal systolic blood pressure.

    LENUS (Irish Health Repository)

    Mitchell, T H

    2012-02-03

    PURPOSE: Microalbuminuria predicts early mortality in non-insulin-dependent-diabetes mellitus patients (NIDDM). Our objective in the present study was to compare and assess the relationship between 24-hour, day and nocturnal ambulatory blood pressure (BP) and urinary albumin excretion rate (UAE) in microalbuminuric and normoalbuminuric NIDDM and in normal control subjects. PATIENTS AND METHODS: In the present cross-sectional study, 24 hour ambulatory BP (daytime BP and nocturnal BP) and HbA1c were compared in microalbuminuric (n = 10) and nonmicroalbuminuric NIDDM patients (n = 10) and in nondiabetic controls (n = 9). None of the patients were taking antihypertensive agents. RESULTS: In the microlbuminuric group, whereas 24 hour and daytime systolic BP differed significantly from control values (P < 0.025 and P < 0.05 respectively), there was no difference between diabetic groups. However, nocturnal systolic BP in the microalbuminuric group was significantly higher than in the normoalbuminuric diabetic patients (139 vs. 125) (P < 0.05) and a significant difference was also found between the NIDDM patients and the control group (139, 125 vs. 114) (P < 0.025). In multiple regression analysis, only nocturnal systolic BP showed a significant relationship with UAE (P < 0.05). CONCLUSIONS: We suggest that the higher nocturnal systolic blood pressure seen in our microalbuminuric NIDDM patients may contribute to the increased morbidity in this group.

  1. Nocturnal Polyuria and Hypertension in Patients with Lifestyle Related Diseases and Overactive Bladder.

    Science.gov (United States)

    Yokoyama, Osamu; Nishizawa, Osamu; Homma, Yukio; Takeda, Masayuki; Gotoh, Momokazu; Kakizaki, Hidehiro; Akino, Hironobu; Hayashi, Koichi; Yonemoto, Koji

    2017-02-01

    The objective of this multicenter cross-sectional study was to investigate the relationship of nocturnal polyuria in patients with common lifestyle related diseases and overactive bladder, with special attention to hypertension. After baseline assessment, patients recorded 24-hour urinary frequency/volume, blood pressure and heart rate for 3 days. They were stratified into 4 groups based on mean blood pressure, including no hypertension, and controllable, untreated and uncontrolled hypertension, respectively. The 2,353 eligible patients, who had urinary urgency once or more per week and 1 or more nocturnal toilet visits, were enrolled from 543 sites in Japan. Of these patients complete data, including the 24-hour frequency volume chart, were collected from 1,271. Multivariable analyses showed a statistically significant association of nocturnal polyuria with increasing age (OR 1.04, 95% CI 1.02-1.05, p polyuria in women alone (p = 0.01 and 0.03, respectively). Lower urinary tract symptoms suggestive of benign prostatic hyperplasia were significantly associated with nocturnal polyuria in men alone (p polyuria was significantly associated with age, male gender, and untreated hypertension in patients with lifestyle related diseases and overactive bladder. The association between hypertension and nocturnal polyuria was significant in women alone. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  2. The multidimensional correlates associated with short nocturnal sleep duration and subjective insomnia among Taiwanese adolescents.

    Science.gov (United States)

    Yen, Cheng-Fang; Ko, Chih-Hung; Yen, Ju-Yu; Cheng, Chung-Ping

    2008-11-01

    The aim of this study was to examine the correlates associated with short nocturnal sleep duration and subjective insomnia, including individual factors, family factors, peer factors, school factors, and the problematic use of high-tech devices among a large-scale representative population of Taiwanese adolescents. Cross-sectional study. A total of 23 junior high and 29 senior high/vocational schools were randomly selected across southern Taiwan. Eight thousand four adolescent students. N/A. The multidimensional correlates associated with short nocturnal sleep duration and subjective insomnia were examined using chi2 automatic interaction detection analysis and logistic regression analysis models. The results indicated that an older age, self-reported depression, being in the third year of school, drinking coffee at night, and problematic Internet use were significantly associated with short nocturnal sleep duration in adolescents. Furthermore, self-reported depression, low school affinity, high family conflict, low connectedness to their peer group, and problematic Internet use were associated with subjective insomnia in adolescents. The results of this study indicate that a variety of individual, family, peer, and school factors were associated with short nocturnal sleep duration and subjective insomnia in adolescents. Furthermore, the correlates of short sleep duration were not identical to those of subjective insomnia. Parents and health professionals should be wary of sleep patterns among adolescents who have the identified correlates of short nocturnal sleep duration and subjective insomnia.

  3. Separating selection by diurnal and nocturnal pollinators on floral display and spur length in Gymnadenia conopsea.

    Science.gov (United States)

    Sletvold, Nina; Trunschke, Judith; Wimmergren, Carolina; Agren, Jon

    2012-08-01

    Most plants attract multiple flower visitors that may vary widely in their effectiveness as pollinators. Floral evolution is expected to reflect interactions with the most important pollinators, but few studies have quantified the contribution of different pollinators to current selection on floral traits. To compare selection mediated by diurnal and nocturnal pollinators on floral display and spur length in the rewarding orchid Gymnadenia conopsea, we manipulated the environment by conducting supplemental hand-pollinations and selective pollinator exclusions in two populations in central Norway. In both populations, the exclusion of diurnal pollinators significantly reduced seed production compared to open pollination, whereas the exclusion of nocturnal pollinators did not. There was significant selection on traits expected to influence pollinator attraction and pollination efficiency in both the diurnal and nocturnal pollination treatment. The relative strength of selection among plants exposed to diurnal and nocturnal visitors varied among traits and populations, but the direction of selection was consistent. The results suggest that diurnal pollinators are more important than nocturnal pollinators for seed production in the study populations, but that both categories contribute to selection on floral morphology. The study illustrates how experimental manipulations can link specific categories of pollinators to observed selection on floral traits, and thus improve our understanding of how species interactions shape patterns of selection.

  4. Adaptive genomic evolution of opsins reveals that early mammals flourished in nocturnal environments.

    Science.gov (United States)

    Borges, Rui; Johnson, Warren E; O'Brien, Stephen J; Gomes, Cidália; Heesy, Christopher P; Antunes, Agostinho

    2018-02-05

    Based on evolutionary patterns of the vertebrate eye, Walls (1942) hypothesized that early placental mammals evolved primarily in nocturnal habitats. However, not only Eutheria, but all mammals show photic characteristics (i.e. dichromatic vision, rod-dominated retina) suggestive of a scotopic eye design. Here, we used integrative comparative genomic and phylogenetic methodologies employing the photoreceptive opsin gene family in 154 mammals to test the likelihood of a nocturnal period in the emergence of all mammals. We showed that mammals possess genomic patterns concordant with a nocturnal ancestry. The loss of the RH2, VA, PARA, PARIE and OPN4x opsins in all mammals led us to advance a probable and most-parsimonious hypothesis of a global nocturnal bottleneck that explains the loss of these genes in the emerging lineage (> > 215.5 million years ago). In addition, ancestral character reconstruction analyses provided strong evidence that ancestral mammals possessed a nocturnal lifestyle, ultra-violet-sensitive vision, low visual acuity and low orbit convergence (i.e. panoramic vision). Overall, this study provides insight into the evolutionary history of the mammalian eye while discussing important ecological aspects of the photic paleo-environments ancestral mammals have occupied.

  5. Reproductive biology of Echinopsis terscheckii (Cactaceae): the role of nocturnal and diurnal pollinators.

    Science.gov (United States)

    Ortega-Baes, P; Saravia, M; Sühring, S; Godínez-Alvarez, H; Zamar, M

    2011-01-01

    The aim of this study was to analyse the reproductive biology of Echinopsis terscheckii, a species endemic to northwest Argentina that has nocturnal flowers. We expected that this species had a generalised pollination system, with moths and diurnal visitors as the primary pollinators. To test this, we studied the floral biology, breeding system and floral visitors of this species and the effectiveness of nocturnal and diurnal visitors. Floral biology was defined based on floral morphology, floral cycle and nectar production of the flowers. The breeding system and relative contributions of diurnal and nocturnal visitors to fruit and seed set were analysed through field experiments. E. terscheckii flowers opened at sunset and closed the following day. The peak of nectar production occurred at midnight. Flowers were determined to be self-incompatible. Moths, bees and birds were identified as floral visitors. Moths were the most frequent visitors at night, whereas bees were the most frequent visitors during the day. Fruit production by diurnal pollinators was less than that by nocturnal pollinators; among all floral visitors, moths were the most effective pollinators. We have demonstrated for the first time that moths are the primary pollinators of columnar cacti of the genus Echinopsis. Our results suggest that moths might be important pollinators of columnar cactus species with nocturnal flowers in the extra-tropical deserts of South America. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.

  6. The association between nocturia and nocturnal polyuria in clinical and epidemiological studies: a systematic review and meta-analyses.

    Science.gov (United States)

    Hofmeester, Ilse; Kollen, Boudewijn J; Steffens, Martijn G; Bosch, J L H Ruud; Drake, Marcus J; Weiss, Jeffrey P; Blanker, Marco H

    2014-04-01

    We determined the relationship between nocturia and nocturnal polyuria. The PubMed® and Embase® databases were searched for studies written in English, German, French or Dutch with original data on adult participants in an investigation of the relationship between nocturia and nocturnal polyuria. A meta-analysis of the difference in mean nocturnal voiding frequencies between patients with and without nocturnal polyuria was conducted. Nocturnal polyuria risk was compared between participants with and without nocturia, and the resulting odds ratio was subsequently converted to relative risk with 95% CIs. From 511 references identified we selected 78 publications of 66 studies, 15 of which met the inclusion criteria for this study. Quality scores of studies were generally high for internal validity but low for external validity. In 7 studies (1,416 participants) we estimated a standardized mean difference of 0.59 (95% CI 0.29-0.89) for nocturnal voids between nocturnal polyuria and nonnocturnal polyuria cases. In 8 other studies (with 2,320 participants) we calculated a pooled OR of 4.99 (3.92-6.37) for nocturnal polyuria in individuals with nocturia. The corresponding RR, based on a nocturnal polyuria risk in the pooled population of 63.8%, was 1.41 (1.37-1.44). The association between nocturia and nocturnal polyuria is apparent and robust. However, the clinical importance of the association appears to be less obvious than previously suggested based on single studies. The observed high prevalence of nocturnal polyuria, as a result of the applied International Continence Society definition, may be responsible for this discrepancy. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  7. Preface: GEWEX Atmospheric Boundary-layer Study (GABLS) on Stable Boundary Layers

    NARCIS (Netherlands)

    Holtslag, A.A.M.

    2006-01-01

    The Global Energy and Water Cycle Experiment (GEWEX) is a program initiated by the World Climate Research Programme (WCRP) to observe, understand and model the hydrological cycle and the related energy fluxes in the atmosphere, at the land surface and in the upper oceans. Consequently the

  8. Political State Boundary (National)

    Data.gov (United States)

    Department of Transportation — State boundaries with political limit - boundaries extending into the ocean (NTAD). The TIGER/Line Files are shapefiles and related database files (.dbf) that are an...

  9. Allegheny County Municipal Boundaries

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the municipal boundaries in Allegheny County. Data was created to portray the boundaries of the 130 Municipalities in Allegheny County the...

  10. HUD GIS Boundary Files

    Data.gov (United States)

    Department of Housing and Urban Development — The HUD GIS Boundary Files are intended to supplement boundary files available from the U.S. Census Bureau. The files are for community planners interested in...

  11. State Agency Administrative Boundaries

    Data.gov (United States)

    Kansas Data Access and Support Center — This database comprises 28 State agency boundaries and point of contact. The Kansas Geological Survey collected legal descriptions of the boundaries for various...

  12. Stable isotopes labelled compounds

    International Nuclear Information System (INIS)

    1982-09-01

    The catalogue on stable isotopes labelled compounds offers deuterium, nitrogen-15, and multiply labelled compounds. It includes: (1) conditions of sale and delivery, (2) the application of stable isotopes, (3) technical information, (4) product specifications, and (5) the complete delivery programme

  13. Evolutionary Stable Strategy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 9. Evolutionary Stable Strategy: Application of Nash Equilibrium in Biology. General Article Volume 21 Issue 9 September 2016 pp 803- ... Keywords. Evolutionary game theory, evolutionary stable state, conflict, cooperation, biological games.

  14. Nocturnal antihypertensive treatment in patients with type 1 diabetes with autonomic neuropathy and non-dipping of blood pressure during night time

    DEFF Research Database (Denmark)

    Hjortkær, Henrik; Jensen, Tonny; Kofoed, Klaus

    2014-01-01

    INTRODUCTION: Cardiac autonomic neuropathy (CAN) and elevated nocturnal blood pressure are independent risk factors for cardiovascular disease in patients with diabetes. Previously, associations between CAN, non-dipping of nocturnal blood pressure and coronary artery calcification have been...

  15. On boundary superalgebras

    International Nuclear Information System (INIS)

    Doikou, Anastasia

    2010-01-01

    We examine the symmetry breaking of superalgebras due to the presence of appropriate integrable boundary conditions. We investigate the boundary breaking symmetry associated with both reflection algebras and twisted super-Yangians. We extract the generators of the resulting boundary symmetry as well as we provide explicit expressions of the associated Casimir operators.

  16. CFD modelling of nocturnal low-level jet effects on wind energy related variables

    Science.gov (United States)

    Sogachev, Andrey; Mann, Jakob; Dellwik, Ebba; Ejsing Jørgensen, Hans

    2010-05-01

    The development of a wind speed maximum in the nocturnal boundary layer, referred to as a low-level jet (LLJ), is a common feature of the vertical structure of the atmospheric boundary layer (ABL). Characterizing and understanding LLJ streams is growing in importance as wind turbines are being built larger and taller to take advantage of higher wind speeds at increased heights. We used a computational fluid dynamics (CFD) model to explore LLJs effect on wind speed, wind directional and speed shear inside the surface layer 40 - 130 m, where their physical measurements are not trivial and still rare today. We used the one-dimensional version of the ABL model SCADIS (Sogachev et al. 2002: Tellus 54:784-819). The unique feature of the model, based on a two-equation closure approach, is the treatment of buoyancy effects in a universal way, which overcomes the uncertainties with model coefficients for non-shear source/sink terms (Sogachev, 2009: Boundary Layer Meteor. 130:423-435). From a variety of mechanisms suggested for formation of LLJs, such as inertial oscillations, baroclinicity over sloping terrain, and land-sea breeze effects, the one-dimensional ABL model is capable of simulating only the first one. However, that mechanism, which is caused by the diurnal oscillation of eddy viscosity, is often responsible for jet formation. Sensitivity tests carried out showed that SCADIS captures the most prominent features of the LLJ, including its vertical structure as well as its diurnal phase and amplitude. We simulated ABL pattern under conditions typical for LLJ formation (a fair day on July 1, a flat low-roughness underlying surface) at 30 and 50o latitudes. Diurnal variability of wind speed and turbulence intensity at four levels of 40, 70, 100 and 130 m above ground and of wind and directional shear between those levels were analysed. Despite of small differences in LLJ structure the properties of LLJ important for wind energy production are still common for two

  17. [Urodynamic changes in patients with obstructive sleep apnea-hypopnea syndrome and nocturnal polyuria].

    Science.gov (United States)

    Hu, Ke; Tu, Zuo-sheng; Lü, Sheng-qi; Li, Qing-quan; Chen, Xue-qin

    2011-03-01

    To investigate the urodynamic changes in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) and nocturnal polyuria. From Sept. 2002 to Jun. 2008, 23 patients with nocturnal polyuria were diagnosed as having OSAHS by polysomnography (PSG). The number and output of nocturia, the osmotic pressure and the excretion of Na(+) were recorded during both the PSG night and CPAP titrating night. Plasma levels of brain natriuretic peptide (BNP) and atrial natriuretic peptides (ANP) were also measured at 11PM in the 2 nights and 7AM in the next mornings. Urodynamic studies including urine flow, bladder pressure during filling, pressure-flow study during voiding and urethral pressure were carried out in these patients. Urodynamic studies were performed again after treatment with CPAP for 3 months. PSG showed that the patients with nocturnal polyuria had moderate to severe OSAHS, in which the apnea-hypopnea index (AHI) being 48 ± 15 events per hour. The number of nocturnal voiding during the PSG night was more than that during the CPAP titrating night. During the PSG night, the output of nocturia, the nocturia excretion of Na(+), ANP levels (at 7am in the next morning after PSG night) increased and the osmotic pressure of nocturia decreased. CPAP therapy could reverse these abnormalities. The main characteristics of urodynamics in these patients included weak detrusor contraction, hypoesthesia in filling cystometry, and decreased bladder compliance, and detrusor external sphincter dyssynergia. After 3 months of CPAP treatment, both the motility of the detrusor of bladder and the bladder compliance improved. CPAP therapy can effectively reverse the nocturnal polyuria in OSAHS patients. In OSAHS patients, the features of nocturia, including the changes of output, osmotic pressure and the excretion of Na(+), may be related to the secretion of high-level of ANP. During the course of chronic progressively OSAHS pathophysiology, detrusor function of bladder may be damaged

  18. Moonstruck primates: owl monkeys (Aotus need moonlight for nocturnal activity in their natural environment.

    Directory of Open Access Journals (Sweden)

    Eduardo Fernández-Duque

    2010-09-01

    Full Text Available Primates show activity patterns ranging from nocturnality to diurnality, with a few species showing activity both during day and night. Among anthropoids (monkeys, apes and humans, nocturnality is only present in the Central and South American owl monkey genus Aotus. Unlike other tropical Aotus species, the Azara's owl monkeys (A. azarai of the subtropics have switched their activity pattern from strict nocturnality to one that also includes regular diurnal activity. Harsher climate, food availability, and the lack of predators or diurnal competitors, have all been proposed as factors favoring evolutionary switches in primate activity patterns. However, the observational nature of most field studies has limited an understanding of the mechanisms responsible for this switch in activity patterns. The goal of our study was to evaluate the hypothesis that masking, namely the stimulatory and/or inhibitory/disinhibitory effects of environmental factors on synchronized circadian locomotor activity, is a key determinant of the unusual activity pattern of Azara's owl monkeys. We use continuous long-term (6-18 months 5-min-binned activity records obtained with actimeter collars fitted to wild owl monkeys (n =  10 individuals to show that this different pattern results from strong masking of activity by the inhibiting and enhancing effects of ambient luminance and temperature. Conclusive evidence for the direct masking effect of light is provided by data showing that locomotor activity was almost completely inhibited when moonlight was shadowed during three lunar eclipses. Temperature also negatively masked locomotor activity, and this masking was manifested even under optimal light conditions. Our results highlight the importance of the masking of circadian rhythmicity as a determinant of nocturnality in wild owl monkeys and suggest that the stimulatory effects of dim light in nocturnal primates may have been selected as an adaptive response to

  19. The Relationship Between Child Anxiety Related Disorders and Primary Nocturnal Enuresis.

    Science.gov (United States)

    Salehi, Bahman; Yousefichaijan, Parsa; Rafeei, Mohammad; Mostajeran, Mahssa

    2016-06-01

    Nocturnal enuresis, often called bedwetting or sleep wetting, is a common problem in children after the age of five and may lead to symptoms such as infection, incontinence and frequent urination. This problem refers to a state in which children after the age of five have no control of their urine for six continuous months and it cannot be attributed to any organic factors or drug use. In this study we aimed to study generalized anxiety disorder as one of the possible causes of primary nocturnal enuresis. In this case-control study 180 children with primary nocturnal enuresis and same number of healthy children with a mean age of 7 - 17 years old with the same demographic characteristics were selected. The study took place at Amir Kabir hospital of Arak, Iran during year 2014. After collecting the information, diagnosis was verified based on the diagnostic and statistical manual of mental disorders (DSM) IV-TR criteria. Results were analyzed using the SPSS software (IBM Corp. Released 2011. IBM SPSS Statistics for Windows, version 20.0. Armonk, NY: IBM Corp.). Frequency of generalized anxiety disorder, panic disorder, school phobia, social anxiety, separation anxiety, history of anxiety in mother, history of primary nocturnal enuresis in parent's family and body mass index had a significant difference between the two groups (P = 0.005). With the results obtained from this study we could say that there was a clear significant difference between the two control and patient groups for all subgroups of anxiety disorders such as generalized anxiety disorder and their relationship with primary nocturnal enuresis. Given the higher prevalence of generalized anxiety disorder, panic disorder, school phobia, social anxiety, separation anxiety and comparison with healthy children, it is recommended for all children with primary nocturnal enuresis to be investigated and treated for generalized anxiety disorder.

  20. Self-construing in children with primary mono-symptomatic nocturnal enuresis--an investigation of three measures.

    Science.gov (United States)

    Robinson, Joanne C; Butler, Richard J; Holland, Philip; Doherty-Williams, Dianne

    2003-01-01

    This study aims to measure different aspects of self-construing in children with primary mono-symptomatic nocturnal enuresis. 25 children aged 7-14 years, with nocturnal enuresis were recruited from a paediatric outpatient's unit specialising in enuresis [mean age 10.6 [males], 9.39 [females

  1. Sensor-based evaluation and treatment of nocturnal hypokinesia in Parkinson's disease: An evidence-based review.

    Science.gov (United States)

    Bhidayasiri, Roongroj; Sringean, Jirada; Thanawattano, Chusak

    2016-01-01

    The manifestations of nocturnal movements in Parkinson's disease (PD) are protean, with major disabilities related to nocturnal hypokinesia. While it can be assessed by clinical interviews and screening instruments, these are often inaccurate and prone to recall bias. In light of advances in sensor technology, we explored the use of sensors in the study of nocturnal hypokinesia, by performing a systematic review of the professional literature on this topic. Evidence suggests that nocturnal hypokinesia exists even in patients in the early stages, and PD patients turned significantly less and with much slower speed and acceleration than controls, partly related to low nocturnal dopamine level. We conducted another systematic review to evaluate the evidence of the efficacy of dopaminergic agents in the treatment of nocturnal hypokinesia. Several lines of evidence support the use of long-acting drugs or by continuous administration of short-acting agents to control symptoms. Sensor parameters could be considered as one of the important objective outcomes in future clinical trials investigating potential drugs to treat nocturnal hypokinesia. Physicians should be aware of this technology as it can aid the clinical assessment of nocturnal hypokinesia and enhance the quality of patient care. In addition, the use of sensors currently is being considered for various aspects of research on early diagnosis, treatment, and rehabilitation of PD patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. The nocturnal panic attacks: polysomnographic features and comorbidities

    Directory of Open Access Journals (Sweden)

    LI Yan-lin

    2013-05-01

    Full Text Available Background Panic disorder refers to the repeated or unexpected anxiety or panic attacks. It makes patients feel extreme pain. Although the episodes of most patients with panic disorder happen at daytime, the nocturnal panic attacks (NPA are quite common. Paients pay more attention to NPA. Insomnia is more serious in patients with NPA than those patients with panic disorder attack at daytime. Many patients may occur anxiety and avoidance behavior after NPA. Patients are often afraid of sleeping, or even do not sleep. The aim of this study is to analyze polysomnographic (PSG parameter changes and clinical concomitant symptoms of patietns with NPA, to explore the characteristics of sleep, in order to provide better diagnosis, differential diagnosis and treatment for these patients. Methods The features of sleep of 20 NPA patients and 23 healthy controls were monitored by video-PSG. Hamilton Anxiety Rating Scale (HAMA and Hamilton Depression Rating Scale (HAMD were used to assess the state of anxiety, depression, and dyssomnia of the patients. Results In comparison with normal control group, the NPA group showed shortened total sleep time (TST, decreased sleep efficiency (SE and sleep maintenance rate, delayed arousal time, increased number of arousal and number of arousal episode longer than 5 minutes, increased percentage of non-rapid eye movement (NREM sleep stage Ⅰ, decreased percentage of NREM sleep stageⅢ and percentage of rapid eye movement (REM sleep (P 0.05, for all. In NPA group, there were 13 cases (13/20 with anxiety, 17 (17/20 with depression, 13 cases/times (13/20 with difficulty of falling asleep, 17 cases/times (17/20 with difficulties in maintaining sleep (frequent arousals and difficult to fall asleep again and 7 cases/times (7/20 with wake up early. Conclusion NPA patients present decreased deep sleep, increased shallow sleep and poor sleep quality, and are mostly accompanied with mild or moderate depression and (or anxiety

  3. Prevalence of nocturnal hypoglycemia in first trimester of pregnancy in patients with insulin treated diabetes mellitus

    DEFF Research Database (Denmark)

    Hellmuth, Ellinor Adelheid; Damm, P; Mølsted-Pedersen, L

    2000-01-01

    BACKGROUND: Excellent metabolic control before conception and during diabetic pregnancies is the aim in order to avoid malformations and perinatal morbidity. Since an inverse correlation between median blood glucose concentration (BG) and hypoglycemia as well as a high prevalence of nocturnal...... the night, caused by either discomfort or cannula problems. Of the remaining 43 patients, 16 (37%) had at least one blood glucose ... of pregnancy in insulin treated patients. Only one patient registered the hypoglycemia. Nocturnal hypoglycemia could be predicted in the majority of patients by measurements of BG before bedtime....

  4. Effect of melatonin on nocturnal blood pressure: meta-analysis of randomized controlled trials

    Directory of Open Access Journals (Sweden)

    Laudon M

    2011-09-01

    Full Text Available Ehud Grossman1,4, Moshe Laudon2, Nava Zisapel2,31Department of Internal Medicine D and Hypertension Unit, The Chaim Sheba Medical Center, Tel-Hashomer, Israel; 2Neurim Pharmaceuticals Ltd, Tel Aviv, Israel and 3Department of Neurobiology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel; 4Sackler School of Medicine, Tel Aviv University, Tel Aviv, IsraelBackground: Patients with nocturnal hypertension are at higher risk for cardiovascular complications such as myocardial infarction and cerebrovascular insult. Published studies inconsistently reported decreases in nocturnal blood pressure with melatonin.Methods: A meta-analysis of the efficacy and safety of exogenous melatonin in ameliorating nocturnal blood pressure was performed using a random effects model of all studies fitting the inclusion criteria, with subgroup analysis of fast-release versus controlled-release preparations.Results: Seven trials (three of controlled-release and four of fast-release melatonin with 221 participants were included. Meta-analysis of all seven studies did not reveal significant effects of melatonin versus placebo on nocturnal blood pressure. However, subgroup analysis revealed that controlled-release melatonin significantly reduced nocturnal blood pressure whereas fast-release melatonin had no effect. Systolic blood pressure decreased significantly with controlled-release melatonin (-6.1 mmHg; 95% confidence interval [CI] -10.7 to -1.5; P = 0.009 but not fast-release melatonin (-0.3 mmHg; 95% CI -5.9 to 5.30; P = 0.92. Diastolic blood pressure also decreased significantly with controlled-release melatonin (-3.5 mmHg; 95% CI -6.1 to -0.9; P = 0.009 but not fast-release melatonin (-0.2 mmHg; 95% CI -3.8 to 3.3; P = 0.89. No safety concerns were raised.Conclusion: Add-on controlled-release melatonin to antihypertensive therapy is effective and safe in ameliorating nocturnal hypertension, whereas fast-release melatonin is ineffective. It is necessary

  5. Unusual nocturnal feeding by Brown Rock-chat Cercomela fusca (Passeriformes: Muscicapidae in Bikaner, Rajasthan, India

    Directory of Open Access Journals (Sweden)

    P. Singh

    2009-04-01

    Full Text Available Brown Rock-chat is a diurnal insectivorous bird commonly associated with human habitations. I report here nocturnal foraging of the species in and around Bikaner in Rajasthan. The birds showed a marked bimodal activity during their nocturnal foraging which peaked in early morning and late evening hours. Bright sodium-vapour lights that attracted a horde of insects during monsoons offered ideal foraging opportunities for the birds. This behavior is explained here as an adaptation to maximize their food intake during the period when the birds breed and their nutritional requirements are naturally high.

  6. Impact of the International Continence Society (ICS) report on the standardisation of terminology in nocturia on the quality of reports on nocturia and nocturnal polyuria : a systematic review

    NARCIS (Netherlands)

    Hofmeester, Ilse; Kollen, Boudewijn J.; Steffens, Martijn G.; Bosch, J. L. H. Ruud; Drake, Marcus J.; Weiss, Jeffrey P.; Blanker, Marco H.

    Objective To systematically review and evaluate the impact of the International Continence Society (ICS)-2002 report on standardisation of terminology in nocturia, on publications reporting on nocturia and nocturnal polyuria (NP). In 2002, the ICS defined NP as a Nocturnal Polyuria Index (nocturnal

  7. Normal modified stable processes

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler; Shephard, N.

    2002-01-01

    Gaussian (NGIG) laws. The wider framework thus established provides, in particular, for added flexibility in the modelling of the dynamics of financial time series, of importance especially as regards OU based stochastic volatility models for equities. In the special case of the tempered stable OU process......This paper discusses two classes of distributions, and stochastic processes derived from them: modified stable (MS) laws and normal modified stable (NMS) laws. This extends corresponding results for the generalised inverse Gaussian (GIG) and generalised hyperbolic (GH) or normal generalised inverse...

  8. Applications of stable isotopes

    International Nuclear Information System (INIS)

    Letolle, R.; Mariotti, A.; Bariac, T.

    1991-06-01

    This report reviews the historical background and the properties of stable isotopes, the methods used for their measurement (mass spectrometry and others), the present technics for isotope enrichment and separation, and at last the various present and foreseeable application (in nuclear energy, physical and chemical research, materials industry and research; tracing in industrial, medical and agronomical tests; the use of natural isotope variations for environmental studies, agronomy, natural resources appraising: water, minerals, energy). Some new possibilities in the use of stable isotope are offered. A last chapter gives the present state and forecast development of stable isotope uses in France and Europe

  9. Analysing Stable Time Series

    National Research Council Canada - National Science Library

    Adler, Robert

    1997-01-01

    We describe how to take a stable, ARMA, time series through the various stages of model identification, parameter estimation, and diagnostic checking, and accompany the discussion with a goodly number...

  10. Self-similar magnetohydrodynamic boundary layers

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, Manuel; Lastra, Alberto, E-mail: mnjmhd@am.uva.e [Departamento de Analisis Matematico, Universidad de Valladolid, 47005 Valladolid (Spain)

    2010-10-15

    The boundary layer created by parallel flow in a magnetized fluid of high conductivity is considered in this paper. Under appropriate boundary conditions, self-similar solutions analogous to the ones studied by Blasius for the hydrodynamic problem may be found. It is proved that for these to be stable, the size of the Alfven velocity at the outer flow must be smaller than the flow velocity, a fact that has a ready physical explanation. The process by which the transverse velocity and the thickness of the layer grow with the size of the Alfven velocity is detailed.

  11. Self-similar magnetohydrodynamic boundary layers

    International Nuclear Information System (INIS)

    Nunez, Manuel; Lastra, Alberto

    2010-01-01

    The boundary layer created by parallel flow in a magnetized fluid of high conductivity is considered in this paper. Under appropriate boundary conditions, self-similar solutions analogous to the ones studied by Blasius for the hydrodynamic problem may be found. It is proved that for these to be stable, the size of the Alfven velocity at the outer flow must be smaller than the flow velocity, a fact that has a ready physical explanation. The process by which the transverse velocity and the thickness of the layer grow with the size of the Alfven velocity is detailed.

  12. EFFECTS OF BUDESONIDE AND BAMBUTEROL ON CIRCADIAN VARIATION OF AIRWAY RESPONSIVENESS AND NOCTURNAL SYMPTOMS OF ASTHMA

    NARCIS (Netherlands)

    WEMPE, JB; TAMMELING, EP; POSTMA, DS; AUFFARTH, B; TEENGS, JP; KOETER, GH

    Effects of the inhaled corticosteroid budesonide and the oral beta-agonist bambuterol on the nocturnal worsening of asthma were studied in patients with allergic asthma with a circadian peak expiratory flow variation greater-than-or-equal-to 15% (group 1, n = 8) and

  13. Nocturnal Orgasm in College Women: Its Relation to Dreams and Anxiety Associated with Sexual Factors

    Science.gov (United States)

    Henton, Comradge L.

    1976-01-01

    A total of 774 female undergraduates were administered a structured questionnaire and an anxiety scale. It was found that women do experience nocturnal orgasms during sleep. Differences were found according to year at school as well as a positive correlation between level of anxiety and sexual excitement. (MS)

  14. Effects of a Heat Wave on Nocturnal Stomatal Conductance in Eucalyptus camaldulensis

    Directory of Open Access Journals (Sweden)

    Víctor Resco de Dios

    2018-06-01

    Full Text Available Nocturnal transpiration constitutes a significant yet poorly understood component of the global water cycle. Modeling nocturnal transpiration has been complicated by recent findings showing that stomata respond differently to environmental drivers over day- vs. night-time periods. Here, we propose that nocturnal stomatal conductance depends on antecedent daytime conditions. We tested this hypothesis across six genotypes of Eucalyptus camaldulensis Dehnh. growing under different CO2 concentrations (ambient vs. elevated and exposed to contrasting temperatures (ambient vs. heat wave for four days prior to the night of measurements, when all plants experienced ambient temperature conditions. We observed significant effects after the heat wave that led to 36% reductions in nocturnal stomatal conductance. The response was partly driven by changes in daytime stomatal behavior but additional factors may have come into play. We also observed significant differences in response to the heat wave across genotypes, likely driven by local adaptation to their climate of origin, but CO2 played no effect. Stomatal models may need to incorporate the role of antecedent effects to improve projections particularly after drastic changes in the environment such as heat waves.

  15. Prognostic value of nocturnal pulse oximetry in patients with heart failure.

    Science.gov (United States)

    Rivera-López, Ricardo; Jordán-Martínez, Laura; López-Fernández, Silvia; Rivera-Fernandez, Ricardo; Tercedor, Luis; Sáez-Roca, Germán

    2018-05-23

    To analyze the prognostic value of nocturnal hypoxemia measured with portable nocturnal pulse-oximetry in patients hospitalized due to heart failure and its relation to mortality and hospital readmission. We included 38 patients who were admitted consecutively to our unit with the diagnosis of decompensated heart failure. Pulse-oximetry was considered positive for hypoxemia when more than 10 desaturations per hour were recorded during sleep. Follow-up was performed for 30.3 (standard deviation [SD] 14.2) months, the main objective being a combined endpoint of all-cause mortality and hospital readmission due to heart failure. The average age was 70.7 (SD 10.7) years, 63.3% were males. Pulse-oximetry was considered positive for hypoxemia in 27 (71%) patients. Patients with positive pulse-oximetry had the most frequent endpoint (9.1% [1] vs. 61.5% [16], P = 0.003). After multivariate analysis, continuous nocturnal hypoxemia was related to the combined endpoint (HR = 8.37, 1.19-68.4, P = 0.03). Patients hospitalized for heart failure and nocturnal hypoxemia measured with portable pulse-oximeter have an increased risk of hospital readmission and death. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  16. Field studies of transport and dispersion of atmospheric tracers in nocturnal drainage flows

    Science.gov (United States)

    Paul H. Gudiksen; Gilbert J. Ferber; Malcolm M. Fowler; Wynn L. Eberhard; Michael A. Fosberg; William R. Knuth

    1984-01-01

    A series of tracer experiments were carried out as part of the Atmospheric Studies in Complex Terrain (ASCOT) program to evaluate pollutant transport and dispersion characteristics of nocturnal drainage flows within a valley in northern California. The results indicate that the degree of interaction of the drainage flows with the larger scale regional flows are...

  17. Improvement of resistant hypertension by nocturnal hemodialysis in a patient with end-stage kidney disease.

    Science.gov (United States)

    Tang, Xiaojing; Hu, Xiaohong; Mei, Changlin; Yu, Shengqiang

    2015-01-01

    Resistant hypertension is a common and refractory complication of hemodialysis (HD) patients and is associated with a higher risk of cardiovascular morbidity and mortality. Here we present a case of resistant hypertension treated successfully by nocturnal HD. A 63-year-old female with end-stage kidney disease was hospitalized for severe headache, objective vertigo and persistent vomiting for 1 month on February 6, 2012. She had been on intermittent HD for 3 months, and her blood pressure maintained 200-240/100-130 mm Hg even after using 7 kinds of antihypertensive drugs including olmesartan, benazepril, nitrendipine, arotinolol, terazosin, clonidine and torasemide. A CT of the abdomen revealed a mild hyperplasia of the left adrenal gland (fig. 1). However, plasma renin, angiotensin and aldosterone were all within the normal range. Nocturnal extended HD was initiated with a blood flow rate of 150 ml/min and a dialysis time of 7 h. After 3 months of nocturnal HD, all symptoms were relieved and her systolic blood pressure started to decrease by 10-20 mm Hg. Six months later, the predialysis blood pressure was decreased to 140-160/90-100 mm Hg and the antihypertensive drugs were reduced to 4 kinds. Meanwhile, the blood biochemical parameters including hemoglobin, serum calcium, phosphate and parathyroid hormone were all controlled well during 2 years of treatment. This case indicates that nocturnal extended HD is probably a promising and effective choice for resistant hypertension in HD patients.

  18. Nocturnal airflow obstruction, histamine, and the autonomic central nervous system in children with allergic asthma

    NARCIS (Netherlands)

    van Aalderen, W. M.; Postma, D. S.; Koëter, G. H.; Knol, K.

    1991-01-01

    A study was carried out to investigate whether an imbalance in the autonomic nervous system or release of histamine, or both, is responsible for the nocturnal increase in airflow obstruction in asthmatic children. The study comprised 18 children with allergic asthma, nine with (group 1) and nine

  19. Retinal and optical adaptations for nocturnal vision in the halictid bee Megalopta genalis.

    Science.gov (United States)

    Greiner, Birgit; Ribi, Willi A; Warrant, Eric J

    2004-06-01

    The apposition compound eye of a nocturnal bee, the halictid Megalopta genalis, is described for the first time. Compared to the compound eye of the worker honeybee Apis mellifera and the diurnal halictid bee Lasioglossum leucozonium, the eye of M. genalis shows specific retinal and optical adaptations for vision in dim light. The major anatomical adaptations within the eye of the nocturnal bee are (1) nearly twofold larger ommatidial facets and (2) a 4-5 times wider rhabdom diameter than found in the diurnal bees studied. Optically, the apposition eye of M. genalis is 27 times more sensitive to light than the eyes of the diurnal bees. This increased optical sensitivity represents a clear optical adaptation to low light intensities. Although this unique nocturnal apposition eye has a greatly improved ability to catch light, a 27-fold increase in sensitivity alone cannot account for nocturnal vision at light intensities that are 8 log units dimmer than during daytime. New evidence suggests that additional neuronal spatial summation within the first optic ganglion, the lamina, is involved.

  20. Regional variations in nocturnal fluctuations in subcutaneous blood flow rate in the lower leg of man

    DEFF Research Database (Denmark)

    Sindrup, J H; Kastrup, J; Jørgensen, B

    1991-01-01

    was observed in both series concerning the duration of the period from going to bed until the hyperaemia phase (P less than 0.001). The mechanisms involved in the nightly subcutaneous hyperaemia are at present unknown. The sudden, synchronized increase in nocturnal subcutaneous blood flow points to a central...... nervous or humoral elicitation, although local metabolic factors might participate as well....

  1. EVOLUTION OF THE NOCTURNAL INVERSION LAYER AT AN URBAN AND NONURBAN LOCATION

    Science.gov (United States)

    The evolutionary cycle of the nocturnal radiation inversion layer from formation until dissipation under fair weather conditions was investigated by time-series analyses of observations of inversion base and top heights, and inversion strength at an urban and a nonurban site in S...

  2. Stop early to travel fast: modelling risk-averse scheduling among nocturnally migrating birds

    NARCIS (Netherlands)

    McLaren, J.D.; Shamoun-Baranes, J.; Bouten, W.

    2013-01-01

    Many migrating birds divide their journeys into nocturnal flights interspersed by stopovers where they build up energy reserves (fuel) for subsequent flights. Given the difficulty in monitoring fuel loads of individual migrants over long distances, theoretical models are often used to interpret

  3. Circadian phase and period responses to light stimuli in two nocturnal rodents

    NARCIS (Netherlands)

    Sharma, Vijay Kumar; Daan, Serge

    2002-01-01

    We report period response curves (tauRC) for two nocturnal Murid species from India, Mus booduga and Mus platythrix. We further discuss the method of phase shift estimation in the presence of tau-changes, because such changes pose a serious methodological problem in the estimation of phase shifts.

  4. A Functional Analysis of Circadian Pacemakers in Nocturnal Rodents. IV. Entrainment : Pacemaker as Clock

    NARCIS (Netherlands)

    Pittendrigh, Colin S.; Daan, Serge

    1976-01-01

    1. In the first part of the paper, the model of non-parametric entrainment of circadian pacemakers is tested for the case of nocturnal rodents. The model makes use of the available data on freerunning period (τ) in constant darkness and on phase response curves (PRC) for short light pulses. It is

  5. Nocturnality in synapsids predates the origin of mammals by over 100 million years.

    Science.gov (United States)

    Angielczyk, K D; Schmitz, L

    2014-10-22

    Nocturnality is widespread among extant mammals and often considered the ancestral behavioural pattern for all mammals. However, mammals are nested within a larger clade, Synapsida, and non-mammalian synapsids comprise a rich phylogenetic, morphological and ecological diversity. Even though non-mammalian synapsids potentially could elucidate the early evolution of diel activity patterns and enrich the understanding of synapsid palaeobiology, data on their diel activity are currently unavailable. Using scleral ring and orbit dimensions, we demonstrate that nocturnal activity was not an innovation unique to mammals but a character that appeared much earlier in synapsid history, possibly several times independently. The 24 Carboniferous to Jurassic non-mammalian synapsid species in our sample featured eye morphologies consistent with all major diel activity patterns, with examples of nocturnality as old as the Late Carboniferous (ca 300 Ma). Carnivores such as Sphenacodon ferox and Dimetrodon milleri, but also the herbivorous cynodont Tritylodon longaevus were likely nocturnal, whereas most of the anomodont herbivores are reconstructed as diurnal. Recognizing the complexity of diel activity patterns in non-mammalian synapsids is an important step towards a more nuanced picture of the evolutionary history of behaviour in the synapsid clade. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  6. What makes a good home-based nocturnal seizure detector? A value sensitive design

    NARCIS (Netherlands)

    Van Andel, Judith; Leijten, Frans; Van Delden, Hans; van Thiel, Ghislaine

    2015-01-01

    A device for the in-home detection of nocturnal seizures is currently being developed in the Netherlands, to improve care for patients with severe epilepsy. It is recognized that the design of medical technology is not value neutral: perspectives of users and developers are influential in design,

  7. Nocturnal enuresis in school‑aged children with sickle‑cell anemia ...

    African Journals Online (AJOL)

    2016-05-09

    May 9, 2016 ... socioeconomic class, and sibling history of enuresis were not statistically ... and parental history of childhood enuresis are significant risk factors. .... adolescents with SCA may be at a higher risk of nocturnal ..... Thus, factors which contribute to ... in male children,[30] and more frequent developmental delays ...

  8. Frequency of nocturnal symptoms in asthmatic children attending a hospital out-patient clinic

    NARCIS (Netherlands)

    Meijer, G. G.; Postma, D. S.; Wempe, J. B.; Gerritsen, J.; Knol, K.; van Aalderen, W. M.

    1995-01-01

    Since nocturnal symptoms indicate more severe asthma, we investigated their frequency in a hospital-based population of asthmatic children. Recognition of these symptoms offers the possibility to introduce appropriate treatment. We studied 796 consecutive children with asthma (mean (SD) age 9 (4)

  9. High-intensity endurance training increases nocturnal heart rate variability in sedentary participants

    Directory of Open Access Journals (Sweden)

    A Nummela

    2016-01-01

    Full Text Available The effects of endurance training on endurance performance characteristics and cardiac autonomic modulation during night sleep were investigated during two 4-week training periods. After the first 4-week training period (3 x 40 min per week, at 75% of HRR the subjects were divided into HIGH group (n = 7, who performed three high-intensity endurance training sessions per week; and CONTROL group (n = 8 who did not change their training. An incremental treadmill test was performed before and after the two 4-weektraining periods. Furthermore, nocturnal RR-intervals were recorded after each training day. In the second 4-weektraining period HIGH group increased their V0Zmax (P = 0.005 more than CONTROL group. At the same time, nocturnal HR decreased (P = 0.039 and high-frequency power (HFP increased (P = 0.003 in HIGH group while no changes were observed in CONTROL group. Furthermore, a correlation was observed between the changes in nocturnal HFP and changes in V0Zmax during the second 4-week training period (r = 0.90, P < 0.001. The present study showed that the increased HFP is related to improved VO2max in sedentary subjects suggesting that nocturnal HFP can provide a useful method in monitoring individual responses to endurance training.

  10. Prevalence and risk factors of monosymptomatic nocturnal enuresis in Turkish children

    Directory of Open Access Journals (Sweden)

    Secil Ozkan

    2010-01-01

    Full Text Available Objectives : To determine the prevalence of primary monosymptomatic nocturnal enuresis (PMNE and assess risk factors that can cause this disease. Methods : After the determination of 15 primary schools in the provincial center of Ankara, questionnaires were given to 15,150 students to be answered by their parents. Detailed urologic history was obtained and physical examination applied to the students whose parents answered the questionnaire. After excluding children with polysymptomatic NE, 14060 questionnaires of MNE patients were evaluated. Demographic features with social and medical history of students and their parents, general approach of family to the children, school success of the students and general behavioral attitudes, method of toilet training and the presence of nocturnal enuresis were questioned. Results : MNE was determined in 9.0% (n: 1266 of the students and nocturnal enuresis frequency was higher in boys than girls (P< 0.05. Univariate analysis revealed gender, method of toilet training, sleep problems, school success, and general approach of the family to children and general behavioral attitudes of the children as significant factors. In logistic regression analysis; age, male gender, toilette training with threatening method, deep sleeper, sleep walking, being introverted and shy, significantly increases the risk of nocturnal enuresis. Conclusions : The current study suggests that the methods of toilet training are extremely important to prevent bedwetting and behavioral disorders due to enuresis. Parents should be well-informed about the appropriate toilet training method.

  11. Differential arousal regulation by prokineticin 2 signaling in the nocturnal mouse and the diurnal monkey.

    Science.gov (United States)

    Zhou, Qun-Yong; Burton, Katherine J; Neal, Matthew L; Qiao, Yu; Kanthasamy, Anumantha G; Sun, Yanjun; Xu, Xiangmin; Ma, Yuanye; Li, Xiaohan

    2016-08-18

    The temporal organization of activity/rest or sleep/wake rhythms for mammals is regulated by the interaction of light/dark cycle and circadian clocks. The neural and molecular mechanisms that confine the active phase to either day or night period for the diurnal and the nocturnal mammals are unclear. Here we report that prokineticin 2, previously shown as a circadian clock output molecule, is expressed in the intrinsically photosensitive retinal ganglion cells, and the expression of prokineticin 2 in the intrinsically photosensitive retinal ganglion cells is oscillatory in a clock-dependent manner. We further show that the prokineticin 2 signaling is required for the activity and arousal suppression by light in the mouse. Between the nocturnal mouse and the diurnal monkey, a signaling receptor for prokineticin 2 is differentially expressed in the retinorecipient suprachiasmatic nucleus and the superior colliculus, brain projection targets of the intrinsically photosensitive retinal ganglion cells. Blockade with a selective antagonist reveals the respectively inhibitory and stimulatory effect of prokineticin 2 signaling on the arousal levels for the nocturnal mouse and the diurnal monkey. Thus, the mammalian diurnality or nocturnality is likely determined by the differential signaling of prokineticin 2 from the intrinsically photosensitive retinal ganglion cells onto their retinorecipient brain targets.

  12. The nocturnal bottleneck and the evolution of activity patterns in mammals

    Science.gov (United States)

    Gerkema, Menno P.; Davies, Wayne I. L.; Foster, Russell G.; Menaker, Michael; Hut, Roelof A.

    2013-01-01

    In 1942, Walls described the concept of a ‘nocturnal bottleneck’ in placental mammals, where these species could survive only by avoiding daytime activity during times in which dinosaurs were the dominant taxon. Walls based this concept of a longer episode of nocturnality in early eutherian mammals by comparing the visual systems of reptiles, birds and all three extant taxa of the mammalian lineage, namely the monotremes, marsupials (now included in the metatherians) and placentals (included in the eutherians). This review describes the status of what has become known as the nocturnal bottleneck hypothesis, giving an overview of the chronobiological patterns of activity. We review the ecological plausibility that the activity patterns of (early) eutherian mammals were restricted to the night, based on arguments relating to endothermia, energy balance, foraging and predation, taking into account recent palaeontological information. We also assess genes, relating to light detection (visual and non-visual systems) and the photolyase DNA protection system that were lost in the eutherian mammalian lineage. Our conclusion presently is that arguments in favour of the nocturnal bottleneck hypothesis in eutherians prevail. PMID:23825205

  13. Prevalence and comorbidity of nocturnal wandering in the U.S. adult general population.

    Science.gov (United States)

    Pressman, Mark R

    2013-01-08

    As noted by Ohayon et al., nocturnal wandering (NW) is not synonymous with sleepwalking. NW may also refer to wandering during the night due to epilepsy. Alcohol intoxication can also result in drunken behavior while awake, but this type of cognitive impairment may be undistinguishable from other forms of NW. Dementia and CNS drug effects can also result in NW.

  14. Children Treated for Nocturnal Enuresis: Characteristics and Trends over a 15-Year Period

    Science.gov (United States)

    Kushnir, Jonathan; Kushnir, Baruch; Sadeh, Avi

    2013-01-01

    Background: Nocturnal Enuresis (NE) is one of the most prevalent childhood disorders and has significant negative psychosocial impact on the child and family. Objective: To assess the characteristics of children with NE and trends over a 15-year period. Methods: The study included 18,677 children [11,205 (60%) boys and 7,472 (40%) girls] referred…

  15. Long-term treatment of nocturnal enuresis with desmopressin. A follow-up study

    DEFF Research Database (Denmark)

    Knudsen, U B; Rittig, Søren; Nørgaard, J P

    1991-01-01

    Eight patients with monosymptomatic nocturnal enuresis (age 11-24 years) were investigated prior to and after 24 weeks of desmopressin treatment in order to evaluate the impact on the endogenous vasopressin secretion and urinary output. No effect on plasma vasopressin, diurnal urinary volume, and...

  16. Posterior urethral valve in a six year old boy with nocturnal ...

    African Journals Online (AJOL)

    We report a case of posterior urethral valve (PUV) in a six year old boy with nocturnal eneuresis and failure to thrive as the only presenting symptoms. The clinically occult lesion was only unravelled when micturating cystourethrogram revealed a dilated posterior urethra with a distal narrow stream of opacified urine, bilateral ...

  17. Feeding and survival of two nocturnal cursorial spiders on extrafloral nectar and honeydew sugars

    Science.gov (United States)

    Sugars in the form of extrafloral nectar and honeydews may be important resources for nocturnal cursorial spiders such as Cheiracanthium inclusum (Hentz) and Hibana futilis (Banks). C. inclusum spiderlings given only water survived an average of only 6.1 d. Feeding on cotton extrafloral nectar and m...

  18. The Effects of a Contingency Contracting Program on the Nocturnal Enuresis of Three Children

    Science.gov (United States)

    Stover, Anthony C.; Dunlap, Glen; Neff, Bryon

    2008-01-01

    Objective: This study was conducted to evaluate the effects of a contingency contracting program to eliminate nocturnal enuresis of three children ages 5 to 12. Methods: The program was implemented by the children's primary caregivers, two of whom were foster parents and the third a case worker in the foster care system. The program was a package…

  19. Neutrophil activation and nucleosomes as markers of systemic inflammation in paroxysmal nocturnal hemoglobinuria: effects of eculizumab

    NARCIS (Netherlands)

    Bijnen, S.T. van; Wouters, D.; Mierlo, G.J. van; Muus, P.; Zeerleder, S.

    2015-01-01

    BACKGROUND: Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by complement-mediated hemolysis and a high risk of life-threatening venous and arterial thrombosis. Uncontrolled complement activation and the release of cell-free heme may result in systemic inflammation, neutrophil activation,

  20. Neutrophil activation and nucleosomes as markers of systemic inflammation in paroxysmal nocturnal hemoglobinuria: effects of eculizumab

    NARCIS (Netherlands)

    van Bijnen, S. T. A.; Wouters, D.; van Mierlo, G. J.; Muus, P.; Zeerleder, S.

    2015-01-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by complement-mediated hemolysis and a high risk of life-threatening venous and arterial thrombosis. Uncontrolled complement activation and the release of cell-free heme may result in systemic inflammation, neutrophil activation, and the

  1. Grain boundary migration

    International Nuclear Information System (INIS)

    Dimitrov, O.

    1975-01-01

    Well-established aspects of grain-boundary migration are first briefly reviewed (influences of driving force, temperature, orientation and foreign atoms). Recent developments of the experimental methods and results are then examined, by considering the various driving of resistive forces acting on grain boundaries. Finally, the evolution in the theoretical models of grain-boundary motion is described, on the one hand for ideally pure metals and, on the other hand, in the presence of solute impurity atoms [fr

  2. An investigation of the impact of nocturnal enuresis on children's self-concept.

    Science.gov (United States)

    Collier, J; Butler, R J; Redsell, S A; Evans, J H C

    2002-01-01

    This study sought to evaluate the relationship between the self-esteem and the self-image of children with nocturnal enuresis and to examine these in relation to various aspects of clinical and demographic variables. Previous studies investigating the self-esteem of bedwetting children have had mixed findings. Some studies report that children with nocturnal enuresis have a lower self-esteem than their non-bedwetting peers, but other studies report that children with nocturnal enuresis perceive themselves similarly to non-bedwetting children. However, what have not been studied to date are the self-perceptions of bedwetting children treated in community clinics. A total of 114 bedwetting children treated in community clinics provided the sample. School nurses conducted a routine first-visit assessment, collected baseline demographic and social information and invited children to complete the Butler Self-Image Profile and the Coopersmith Self-Esteem Inventory. Age and extent of wetting were not significantly related to self-concept measures. Girls had significantly (p = 0.008) higher scores on positive self-image compared with boys. Children with secondary enuresis also scored higher on positive self-image compared with those with primary nocturnal enuresis (p = 0.02). The Butler self-image scores indicated a number of significant links between positive self-image and enuresis variables, whereas the Coopersmith self-esteem scores generally failed to distinguish between the enuresis variables and closely reflected those of the negative self-image scores. These findings suggest that amongst children with nocturnal enuresis, the most vulnerable in terms of self-image are male, those with primary enuresis and those with a greater number of wet nights a week.

  3. Nocturnal herbivore-induced plant volatiles attract the generalist predatory earwig Doru luteipes Scudder

    Science.gov (United States)

    Naranjo-Guevara, Natalia; Peñaflor, Maria Fernanda G. V.; Cabezas-Guerrero, Milton F.; Bento, José Maurício S.

    2017-10-01

    Numerous studies have demonstrated that entomophagous arthropods use herbivore-induced plant volatile (HIPV) blends to search for their prey or host. However, no study has yet focused on the response of nocturnal predators to volatile blends emitted by prey damaged plants. We investigated the olfactory behavioral responses of the night-active generalist predatory earwig Doru luteipes Scudder (Dermaptera: Forficulidae) to diurnal and nocturnal volatile blends emitted by maize plants ( Zea mays) attacked by either a stem borer ( Diatraea saccharalis) or a leaf-chewing caterpillar ( Spodoptera frugiperda), both suitable lepidopteran prey. Additionally, we examined whether the earwig preferred odors emitted from short- or long-term damaged maize. We first determined the earwig diel foraging rhythm and confirmed that D. luteipes is a nocturnal predator. Olfactometer assays showed that during the day, although the earwigs were walking actively, they did not discriminate the volatiles of undamaged maize plants from those of herbivore damaged maize plants. In contrast, at night, earwigs preferred volatiles emitted by maize plants attacked by D. saccharalis or S. frugiperda over undamaged plants and short- over long-term damaged maize. Our GC-MS analysis revealed that short-term damaged nocturnal plant volatile blends were comprised mainly of fatty acid derivatives (i.e., green leaf volatiles), while the long-term damaged plant volatile blend contained mostly terpenoids. We also observed distinct volatile blend composition emitted by maize damaged by the different caterpillars. Our results showed that D. luteipes innately uses nocturnal herbivore-induced plant volatiles to search for prey. Moreover, the attraction of the earwig to short-term damaged plants is likely mediated by fatty acid derivatives.

  4. Nocturnal thoracoabdominal asynchrony in house dust mite-sensitive nonhuman primates

    Directory of Open Access Journals (Sweden)

    XiaoJia Wang

    2010-07-01

    Full Text Available XiaoJia Wang, Shaun Reece, Stephen Olmstead, Robert L Wardle, Michael R Van ScottDepartment of Physiology, East Carolina University, Greenville, North Carolina, USAAbstract: Nocturnal bronchoconstriction is a common symptom of asthma in humans, but is poorly documented in animal models. Thoracoabdominal asynchrony (TAA is a noninvasive clinical indication of airway obstruction. In this study, respiratory inductive plethysmography (RIP was used to document nocturnal TAA in house dust mite (HDM-sensitive Cynomolgus macaques. Dynamic compliance (Cdyn and lung resistance (RL measured in anesthetized ­animals at rest and following exposure to HDM allergen, methacholine, and albuterol were highly ­correlated with three RIP parameters associated with TAA, ie, phase angle of the rib cage and abdomen waveforms (PhAng, baseline effort phase relation (eBPRL and effort phase relation (ePhRL. Twenty-one allergic subjects were challenged with HDM early in the morning, and eBPRL and ePhRL were monitored for 20 hours after provocation. Fifteen of the allergic subjects exhibited gradual increases in eBPRL and ePhRL between midnight and 6 am, with peak activity at 4 am. However, as in humans, this nocturnal response was highly variable both between subjects and within subjects over time. The results document that TAA in this nonhuman primate model of asthma is highly correlated with Cdyn and RL, and demonstrate that animals exhibiting acute responses to allergen exposure during the day also exhibit nocturnal TAA.Keywords: nocturnal asthma, late phase asthmatic response, respiratory inductive plethysmography

  5. Neural organisation in the first optic ganglion of the nocturnal bee Megalopta genalis.

    Science.gov (United States)

    Greiner, Birgit; Ribi, Willi A; Wcislo, William T; Warrant, Eric J

    2004-11-01

    Each neural unit (cartridge) in the first optic ganglion (lamina) of the nocturnal bee Megalopta genalis contains nine receptor cell axons (6 short and 3 long visual fibres), and four different types of first-order interneurons, also known as L-fibres (L1 to L4) or lamina monopolar cells. The short visual fibres terminate within the lamina as three different types (svf 1, 2, 3). The three long visual fibres pass through the lamina without forming characteristic branching patterns and terminate in the second optic ganglion, the medulla. The lateral branching pattern of svf 2 into adjacent cartridges is unique for hymenopterans. In addition, all four types of L-fibres show dorso-ventrally arranged, wide, lateral branching in this nocturnal bee. This is in contrast to the diurnal bees Apis mellifera and Lasioglossum leucozonium, where only two out of four L-fibre types (L2 and L4) reach neighbouring cartridges. In M. genalis, L1 forms two sub-types, viz. L1-a and L1-b; L1-b in particular has the potential to contact several neighbouring cartridges. L2 and L4 in the nocturnal bee are similar to L2 and L4 in the diurnal bees but have dorso-ventral arborisations that are twice as wide. A new type of laterally spreading L3 has been discovered in the nocturnal bee. The extensive neural branching pattern of L-fibres in M. genalis indicates a potential role for these neurons in the spatial summation of photons from large groups of ommatidia. This specific adaptation in the nocturnal bee could significantly improve reliability of vision in dim light.

  6. Effects of exercise timing on sleep architecture and nocturnal blood pressure in prehypertensives

    Directory of Open Access Journals (Sweden)

    Fairbrother K

    2014-12-01

    Full Text Available Kimberly Fairbrother,1 Ben Cartner,1 Jessica R Alley,1 Chelsea D Curry,1, David L Dickinson,2 David M Morris,1 Scott R Collier1 1Vascular Biology and Autonomic Studies Laboratory, Department of Health and Exercise Science, 2Department of Economics, Appalachian State University, Boone, NC, USA Background: During nocturnal sleep, blood pressure (BP “dips” compared to diurnal BP, reducing stress on the cardiovascular system. Both the hypotensive response elicited by acute aerobic exercise and sleep quality can impact this dipping response. Purpose: The purpose of this study was to investigate the effects of aerobic exercise timing on circadian BP changes and sleep architecture. Materials and methods: Twenty prehypertensive subjects completed the study. During four test sessions, participants first completed a graded exercise test to exhaustion and then performed 30 minutes of treadmill exercise at 7 am (7A, 1 pm (1P, and 7 pm (7P in a random, counterbalanced order at 65% of the heart rate obtained at peak oxygen uptake. An ambulatory cuff was used to monitor BP responses during 24 hours following exercise, and an ambulatory sleep-monitoring headband was worn during sleep following each session. Results: Aerobic exercise at 7A invoked a greater dip in nocturnal systolic BP than exercise at 1P or 7P, although the greatest dip in nocturnal diastolic BP occurred following 7P. Compared to 1P, 7A also invoked greater time spent in deep sleep. Conclusion: These data indicate that early morning may be the most beneficial time to engage in aerobic exercise to enhance nocturnal BP changes and quality of sleep. Keywords: nocturnal dipping, prehypertension, aerobic exercise

  7. Dark Matters: Challenges of Nocturnal Communication Between Plants and Animals in Delivery of Pollination Services.

    Science.gov (United States)

    Borges, Renee M

    2018-03-01

    The night is a special niche characterized by dim light, lower temperatures, and higher humidity compared to the day. Several animals have made the transition from the day into the night and have acquired unique adaptations to cope with the challenges of performing nocturnal activities. Several plant species have opted to bloom at night, possibly as a response to aridity to prevent excessive water loss through evapotranspiration since flowering is often a water-demanding process, or to protect pollen from heat stress. Nocturnal pollinators have visual adaptations to function under dim light conditions but may also trade off vision against olfaction when they are dependent on nectar-rewarding and scented flowers. Nocturnal pollinators may use CO 2 and humidity cues emanating from freshly-opened flowers as indicators of nectar-rich resources. Some endothermic nocturnal insect pollinators are attracted to thermogenic flowers within which they remain to obtain heat as a reward to increase their energy budget. This review focuses on mechanisms that pollinators use to find flowers at night, and the signals that nocturnally blooming flowers may employ to attract pollinators under dim light conditions. It also indicates gaps in our knowledge. While millions of years of evolutionary time have given pollinators and plants solutions to the delivery of pollination services and to the offering of appropriate rewards, this history of successful evolution is being threatened by artificial light at night. Excessive and inappropriate illumination associated with anthropogenic activities has resulted in significant light pollution which serves to undermine life processes governed by dim light.

  8. From dusk till dawn: nocturnal and diurnal pollination in the epiphyte Tillandsia heterophylla (Bromeliaceae).

    Science.gov (United States)

    Aguilar-Rodríguez, P A; Krömer, T; García-Franco, J G; MacSwiney G, M C

    2016-01-01

    In order to compare the effectiveness of diurnal and nocturnal pollinators, we studied the reproductive biology and pollinators of Tillandsia heterophylla E. Morren, an epiphytic tank bromeliad endemic to southeastern Mexico. Since anthesis in T. heterophylla is predominantly nocturnal but lasts until the following day, we hypothesised that this bromeliad would receive visits from both diurnal and nocturnal visitors, but that nocturnal visitors would be the most effective pollinators, since they arrive first to the receptive flower, and that bats would be the most frequent nocturnal visitors, given the characteristics of the nectar. Flowering of T. heterophylla began in May and lasted until July. The species is fully self-compatible, with an anthesis that lasts for ca. 15-16 h. Mean volume of nectar produced per flower was 82.21 μl, with a mean sugar concentration of 6.33%. The highest volume and concentration of nectar were found at 20:00 h, with a subsequent decline in both to almost zero over the following 12-h period. T. heterophylla has a generalist pollination system, since at least four different morphospecies of visitors pollinate its flowers: bats, moths, hummingbirds and bees. Most of the pollinating visits corresponded to bats and took place in the early evening, when stigma receptivity had already begun; making bats the probable pollinator on most occasions. However, diurnal pollinators may be important as a 'fail-safe' system by which to guarantee the pollination of T. heterophylla. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  9. The vomeronasal complex of nocturnal strepsirhines and implications for the ancestral condition in primates.

    Science.gov (United States)

    Garrett, Eva C; Dennis, John C; Bhatnagar, Kunwar P; Durham, Emily L; Burrows, Anne M; Bonar, Christopher J; Steckler, Natalie K; Morrison, Edward E; Smith, Timothy D

    2013-12-01

    This study investigates the vomeronasal organ in extant nocturnal strepsirhines as a model for ancestral primates. Cadaveric samples from 10 strepsirhine species, ranging from fetal to adult ages, were studied histologically. Dimensions of structures in the vomeronasal complex, such as the vomeronasal neuroepithelium (VNNE) and vomeronasal cartilage (VNC) were measured in serial sections and selected specimens were studied immunohistochemically to determine physiological aspects of the vomeronasal sensory neurons (VSNs). Osteological features corresponding to vomeronasal structures were studied histologically and related to 3-D CT reconstructions. The VNC consistently rests in a depression on the palatal portion of the maxilla, which we refer to as the vomeronasal groove (VNG). Most age comparisons indicate that in adults VNNE is about twice the length compared with perinatal animals. In VNNE volume, adults are 2- to 3-fold larger compared with perinatal specimens. Across ages, a strong linear relationship exists between VNNE dimensions and body length, mass, and midfacial length. Results indicate that the VNNE of nocturnal strepsirhines is neurogenic postnatally based on GAP43 expression. In addition, based on Olfactory Marker Protein expression, terminally differentiated VSNs are present in the VNNE. Therefore, nocturnal strepsirhines have basic similarities to rodents in growth and maturational characteristics of VSNs. These results indicate that a functional vomeronasal system is likely present in all nocturnal strepsirhines. Finally, given that osteological features such as the VNG are visible on midfacial bones, primate fossils can be assessed to determine whether primate ancestors possessed a vomeronasal complex morphologically similar to that of modern nocturnal strepsirhines. Copyright © 2013 Wiley Periodicals, Inc.

  10. Uses of stable isotopes

    International Nuclear Information System (INIS)

    Axente, Damian

    1998-01-01

    The most important fields of stable isotope use with examples are presented. These are: 1. Isotope dilution analysis: trace analysis, measurements of volumes and masses; 2. Stable isotopes as tracers: transport phenomena, environmental studies, agricultural research, authentication of products and objects, archaeometry, studies of reaction mechanisms, structure and function determination of complex biological entities, studies of metabolism, breath test for diagnostic; 3. Isotope equilibrium effects: measurement of equilibrium effects, investigation of equilibrium conditions, mechanism of drug action, study of natural processes, water cycle, temperature measurements; 4. Stable isotope for advanced nuclear reactors: uranium nitride with 15 N as nuclear fuel, 157 Gd for reactor control. In spite of some difficulties of stable isotope use, particularly related to the analytical techniques, which are slow and expensive, the number of papers reporting on this subject is steadily growing as well as the number of scientific meetings organized by International Isotope Section and IAEA, Gordon Conferences, and regional meeting in Germany, France, etc. Stable isotope application development on large scale is determined by improving their production technologies as well as those of labeled compound and the analytical techniques. (author)

  11. The BLLAST field experiment: Boundary-Layer Late Afternoon and Sunset Turbulence

    NARCIS (Netherlands)

    Lothon, M.; Lohou, F.; Pino, D.; Vilà-Guerau De Arellano, J.; Hartogensis, O.K.; Boer, van de A.; Coster, de O.; Moene, A.F.; Steeneveld, G.J.

    2014-01-01

    Due to the major role of the sun in heating the earth's surface, the atmospheric planetary boundary layer over land is inherently marked by a diurnal cycle. The afternoon transition, the period of the day that connects the daytime dry convective boundary layer to the night-time stable boundary

  12. Slow Manifolds and Multiple Equilibria in Stratocumulus-Capped Boundary Layers

    Directory of Open Access Journals (Sweden)

    Junya Uchida

    2010-12-01

    Full Text Available In marine stratocumulus-capped boundary layers under strong inversions, the timescale for thermodynamic adjustment is roughly a day, much shorter than the multiday timescale for inversion height adjustment. Slow-manifold analysis is introduced to exploit this timescale separation when boundary layer air columns experience only slow changes in their boundary conditions. Its essence is that the thermodynamic structure of the boundary layer remains approximately slaved to its inversion height and the instantaneous boundary conditions; this slaved structure determines the entrainment rate and hence the slow evolution of the inversion height. Slow-manifold analysis is shown to apply to mixed-layer model and large-eddy simulations of an idealized nocturnal stratocumulus- capped boundary layer; simulations with different initial inversion heights collapse onto single relationships of cloud properties with inversion height. Depending on the initial inversion height, the simulations evolve toward a shallow thin-cloud boundary layer or a deep, well-mixed thick cloud boundary layer. In the large-eddy simulations, these evolutions occur on two separate slow manifolds (one of which becomes unstable if cloud droplet concentration is reduced. Applications to analysis of stratocumulus observations and to pockets of open cells and ship tracks are proposed.

  13. Calcium stable isotope geochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Gausonne, Nikolaus [Muenster Univ. (Germany). Inst. fuer Mineralogie; Schmitt, Anne-Desiree [Strasbourg Univ. (France). LHyGeS/EOST; Heuser, Alexander [Bonn Univ. (Germany). Steinmann-Inst. fuer Geologie, Mineralogie und Palaeontologie; Wombacher, Frank [Koeln Univ. (Germany). Inst. fuer Geologie und Mineralogie; Dietzel, Martin [Technische Univ. Graz (Austria). Inst. fuer Angewandte Geowissenschaften; Tipper, Edward [Cambridge Univ. (United Kingdom). Dept. of Earth Sciences; Schiller, Martin [Copenhagen Univ. (Denmark). Natural History Museum of Denmark

    2016-08-01

    This book provides an overview of the fundamentals and reference values for Ca stable isotope research, as well as current analytical methodologies including detailed instructions for sample preparation and isotope analysis. As such, it introduces readers to the different fields of application, including low-temperature mineral precipitation and biomineralisation, Earth surface processes and global cycling, high-temperature processes and cosmochemistry, and lastly human studies and biomedical applications. The current state of the art in these major areas is discussed, and open questions and possible future directions are identified. In terms of its depth and coverage, the current work extends and complements the previous reviews of Ca stable isotope geochemistry, addressing the needs of graduate students and advanced researchers who want to familiarize themselves with Ca stable isotope research.

  14. Calcium stable isotope geochemistry

    International Nuclear Information System (INIS)

    Gausonne, Nikolaus; Schmitt, Anne-Desiree; Heuser, Alexander; Wombacher, Frank; Dietzel, Martin; Tipper, Edward; Schiller, Martin

    2016-01-01

    This book provides an overview of the fundamentals and reference values for Ca stable isotope research, as well as current analytical methodologies including detailed instructions for sample preparation and isotope analysis. As such, it introduces readers to the different fields of application, including low-temperature mineral precipitation and biomineralisation, Earth surface processes and global cycling, high-temperature processes and cosmochemistry, and lastly human studies and biomedical applications. The current state of the art in these major areas is discussed, and open questions and possible future directions are identified. In terms of its depth and coverage, the current work extends and complements the previous reviews of Ca stable isotope geochemistry, addressing the needs of graduate students and advanced researchers who want to familiarize themselves with Ca stable isotope research.

  15. Children with monosymptomatic primary nocturnal enuresis – the clinical profile of patients during the first nephrological consultation

    Directory of Open Access Journals (Sweden)

    Anna Krakowska

    2017-12-01

    Full Text Available Introduction: Nocturnal enuresis can be diagnosed in a child older than 5 years of age who involuntarily discharges urine in the wrong time, i.e. at night, and in the wrong place, i.e. in bed. Aim: The aim of the study was to analyse the profile of patients who consult the specialist physician with monosymptomatic primary nocturnal enuresis. Material and methods: The data were collected from a questionnaire completed by guardians of children during the first nephrological consultation. The questions concerned the following: family history of nocturnal enuresis, bedwetting intensity, other urinary tract symptoms, a voiding chart and fluid intake record, number of nocturnal enuresis incidents in 14 days, episodes of nocturia, nocturnal diuresis volume, urinary urgency volume and constipation. Moreover, basic anthropometric measurements were taken. The data were analysed and the following values were calculated: average voided volumes, maximum voided volumes, voided volumes before 5 p.m. and 24-hour diuresis. An analogous analysis was conducted with respect to fluid intake. Results: Most patients were males. The family history of nocturnal enuresis was positive in ⅓ of patients. Approximately ⅓ of patients tended to drink fluids directly before bedtime. The number of patients with sporadic nocturnal enuresis (23–45% was comparable to the number of patients with frequent nocturnal enuresis (28–55%. Nocturnal diuresis suggested nocturnal polyuria in 11 patients (21.6%. Decreased functional bladder capacity was found in almost ¼ of patients (12–23.5%. Conclusions: Monosymptomatic nocturnal enuresis is more common in boys. The family history was positive in ⅓ of patients. Patients and their guardians are not aware of fluid intake restrictions at bedtime. The frequency of nocturnal polyuria and decreased functional bladder capacity is comparable in the investigated patients.

  16. Enurese noturna monossintomática Monosymptomatic nocturnal enuresis

    Directory of Open Access Journals (Sweden)

    Rejane de P. Meneses

    2001-06-01

    profissionais e familiares.OBJECTIVES: Monosymptomatic nocturnal enuresis (MNE plays a very important role in the practice of pediatrics due to its high prevalence, its psychosocial impact, and its controversial etiology and treatment. Our objective was to show that MNE can be a well-defined clinical entity (monosymptomatic, but it can also be a symptom of urinary disorder, thus requiring a completely different therapeutic approach. METHODS: The literature presents numerous publications related to the matter of MNE, thus we tried to select, for this review, the classical and the most recent publications from internationally recognized authors; in addition, we also have a 13-year work experience at the Unit for Urinary Disorders of the Pediatric Nephrology Center of the state of Paraná (Unidade de Distúrbios Miccionais - Centro de Nefrologia Pediatrica do Paraná. RESULTS: The lack of a well-defined, international consensus on the concept, terminology, and classification of MNE is an obstacle for the assessment of the numerous studies found in the literature. The individualization of the MNE clinical entity is the fundamental starting point for providing appropriate guidance for patients. Enuresis can be found in most societies and, thus, it gives way to several interpretations and forms of treatment. There is a consensus, however, on the damage to the self-esteem of enuretic children, and consequently, on the advantage of proper treatment. CONCLUSIONS: In most cases, MNE is kept as a family secret while children remain without proper guidance and treatment and suffering with the lack of understanding and damage to their self-esteem. Doctors should survey patients extensively for MNE during pediatric appointments. It is possible to discard other diagnoses with a detailed survey of habits, quality of the urination, and history of urinary infection and a meticulous physical examination. MNE should be faced as a medical problem worthy of the attention of professionals and

  17. Development of boundary layers

    International Nuclear Information System (INIS)

    Herbst, R.

    1980-01-01

    Boundary layers develop along the blade surfaces on both the pressure and the suction side in a non-stationary flow field. This is due to the fact that there is a strongly fluctuating flow on the downstream blade row, especially as a result of the wakes of the upstream blade row. The author investigates the formation of boundary layers under non-stationary flow conditions and tries to establish a model describing the non-stationary boundary layer. For this purpose, plate boundary layers are measured, at constant flow rates but different interferent frequency and variable pressure gradients. By introducing the sample technique, measurements of the non-stationary boundary layer become possible, and the flow rate fluctuation can be divided in its components, i.e. stochastic turbulence and periodical fluctuation. (GL) [de

  18. Stable isotope studies

    International Nuclear Information System (INIS)

    Ishida, T.

    1992-01-01

    The research has been in four general areas: (1) correlation of isotope effects with molecular forces and molecular structures, (2) correlation of zero-point energy and its isotope effects with molecular structure and molecular forces, (3) vapor pressure isotope effects, and (4) fractionation of stable isotopes. 73 refs, 38 figs, 29 tabs

  19. Interactive Stable Ray Tracing

    DEFF Research Database (Denmark)

    Dal Corso, Alessandro; Salvi, Marco; Kolb, Craig

    2017-01-01

    Interactive ray tracing applications running on commodity hardware can suffer from objectionable temporal artifacts due to a low sample count. We introduce stable ray tracing, a technique that improves temporal stability without the over-blurring and ghosting artifacts typical of temporal post-pr...

  20. The Stable Concordance Genus

    OpenAIRE

    Kearney, M. Kate

    2013-01-01

    The concordance genus of a knot is the least genus of any knot in its concordance class. Although difficult to compute, it is a useful invariant that highlights the distinction between the three-genus and four-genus. In this paper we define and discuss the stable concordance genus of a knot, which describes the behavior of the concordance genus under connected sum.

  1. Stable radiographic scanning agents

    International Nuclear Information System (INIS)

    1976-01-01

    Stable compositions which are useful in the preparation of Technetium-99m-based scintigraphic agents are discussed. They are comprised of ascorbic acid or a pharmaceutically acceptable salt or ester thereof in combination with a pertechnetate reducing agent or dissolved in oxidized pertechnetate-99m (sup(99m)TcO 4 - ) solution

  2. Some stable hydromagnetic equilibria

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J L; Oberman, C R; Kulsrud, R M; Frieman, E A [Project Matterhorn, Princeton University, Princeton, NJ (United States)

    1958-07-01

    We have been able to find and investigate the properties of equilibria which are hydromagnetically stable. These equilibria can be obtained, for example, by wrapping conductors helically around the stellarator tube. Systems with I = 3 or 4 are indicated to be optimum for stability purposes. In some cases an admixture of I = 2 fields can be advantageous for achieving equilibrium. (author)

  3. Stable piecewise polynomial vector fields

    Directory of Open Access Journals (Sweden)

    Claudio Pessoa

    2012-09-01

    Full Text Available Let $N={y>0}$ and $S={y<0}$ be the semi-planes of $mathbb{R}^2$ having as common boundary the line $D={y=0}$. Let $X$ and $Y$ be polynomial vector fields defined in $N$ and $S$, respectively, leading to a discontinuous piecewise polynomial vector field $Z=(X,Y$. This work pursues the stability and the transition analysis of solutions of $Z$ between $N$ and $S$, started by Filippov (1988 and Kozlova (1984 and reformulated by Sotomayor-Teixeira (1995 in terms of the regularization method. This method consists in analyzing a one parameter family of continuous vector fields $Z_{epsilon}$, defined by averaging $X$ and $Y$. This family approaches $Z$ when the parameter goes to zero. The results of Sotomayor-Teixeira and Sotomayor-Machado (2002 providing conditions on $(X,Y$ for the regularized vector fields to be structurally stable on planar compact connected regions are extended to discontinuous piecewise polynomial vector fields on $mathbb{R}^2$. Pertinent genericity results for vector fields satisfying the above stability conditions are also extended to the present case. A procedure for the study of discontinuous piecewise vector fields at infinity through a compactification is proposed here.

  4. Use of natural radioactive tracers for the determination of vertical exchanges in the planetary boundary layer

    International Nuclear Information System (INIS)

    Druilhet, A.; Guedalia, D.; Fontan, J.

    1980-01-01

    Methods for determining the vertical exchange coefficients in the planetary boundary layer using the natural radioactive tracers radon ( 222 Rn), thoron ( 220 Rn), and ThB( 212 Pb) are presented here. Thoron (T/sub 1/2/ = 54 sec) was used for the surface layer. The main results are given for two applications: vertical exchange studies above a flat country and inside a vegetable canopy. Owing to its lifetime, radon can be used for the nocturnal stabilities that have an important concentration increase near the ground. For the planetary layer (0 to 2000m), ThB(T/sub 1/2/ = 10.6 hr) was mainly used

  5. Stable isogeometric analysis of trimmed geometries

    Science.gov (United States)

    Marussig, Benjamin; Zechner, Jürgen; Beer, Gernot; Fries, Thomas-Peter

    2017-04-01

    We explore extended B-splines as a stable basis for isogeometric analysis with trimmed parameter spaces. The stabilization is accomplished by an appropriate substitution of B-splines that may lead to ill-conditioned system matrices. The construction for non-uniform knot vectors is presented. The properties of extended B-splines are examined in the context of interpolation, potential, and linear elasticity problems and excellent results are attained. The analysis is performed by an isogeometric boundary element formulation using collocation. It is argued that extended B-splines provide a flexible and simple stabilization scheme which ideally suits the isogeometric paradigm.

  6. Evaluation of the occurrence and diagnose definitions for Nocturnal Polyuria in Spinal Cord Injured patients during rehabilitation.

    Science.gov (United States)

    Viaene, Annick; Denys, Marie-Astrid; Goessaert, An-Sofie; Claeys, Jana; Raes, Ann; Roggeman, Saskia; Everaert, Karel

    2017-11-03

    Little is known about the occurrence of nocturnal polyuria in spinal cord injured (SCI) patients and the definitions which are preferable in this population. To determine the occurrence of nocturnal polyuria (NP) in spinal cord injured patients during in-patient rehabilitation in the Ghent University Hospital. To study the influence of different time periods (daytime, bed rest and sleep) on the accuracy of the existing diagnose definitions for NP specifically for this type of patients. Retrospective study using patient records. SCI patients during hospital based rehabilitation between 2011 and 2014. Seventy-four SCI patients were selected and their records of frequency-volume charts were examined, after exclusion of unreliable data, forty-seven patients were retained for the current study. Retrospective study using data from frequency-volume charts of either two or three days from patients with SCI. Nocturnal urine production (NUP) and nocturnal polyuria index (NPi) were calculated. There was a significant increase in diuresis, calculated as urine production, between day time and bed rest (p=0.008) and between day time and sleep (p=0.001). All patients showed nocturnal polyuria during a 12-hour night time period (including both bed rest and sleep) and 39 patients showed nocturnal polyuria during the 8 hour period of sleep. There was no significant difference in mean urine production between bed rest and sleep. Prevalence of NP did not significantly differ between the complete or incomplete SCI patients or between patients with higher and lower SCI levels. This study showed that the occurrence of nocturnal polyuria in patients with SCI is high and that it is important to consider which definitions of NP are used for diagnosis. Increase in diuresis is observed during bed rest and sleep and the diagnose is correctly estimated when nocturnal urine production definitions are used in both time periods. In accordance with what was expected, diagnose of NP was

  7. Hot Air Balloon Experiments to Measure the Break-up of the Nocturnal Drainage Flow in Complex Terrain.

    Science.gov (United States)

    Berman, N. S.; Fernando, H. J. S.; Colomer, J.; Levy, M.; Zieren, L.

    1997-11-01

    In order to extend our understanding of the thermally driven atmospheric winds and their influence on pollutant transport, a hot air balloon experiment was conducted over a four day period in June, 1997 near Nogales, Arizona. The focus was on the early morning break-up of the stable down-slope and down-valley flow and the establishment of a convective boundary layer near the surface in the absence of synoptic winds. Temperature, elevation, position and particulate matter concentration were measured aloft and temperature gradient and wind velocity were measured at ground level. The wind velocity within the stable layer was generally less than 1.5 m/s. Just above the stable layer (about 300 meters above the valley) the wind shifted leading to an erosion of the stable layer from above. Surface heating after sunrise created a convective layer which rose from the ground until the stable layer was destroyed. Examples of temperature fluctuation measurements at various elevations during the establishment of the convective flow will be presented. Implications of results for turbulence parameterizations needed for numerical models of wind fields in complex terrain will be discussed.

  8. Administrative Area Boundaries 2 (State Boundaries), Region 9, 2010, NAVTEQ

    Data.gov (United States)

    U.S. Environmental Protection Agency — NAVTEQ Administrative Area Boundaries 2 (State Boundaries) for Region 9. There are five Administrative Area Boundaries layers (1, 2, 3, 4, 5). These layers contain...

  9. Administrative Area Boundaries 4 (City Boundaries), Region 9, 2010, NAVTEQ

    Data.gov (United States)

    U.S. Environmental Protection Agency — NAVTEQ Administrative Area Boundaries 4 (City Boundaries) for Region 9. There are five Administrative Area Boundaries layers (1, 2, 3, 4, 5). These layers contain...

  10. Nocturnal activity patterns of northern myotis (Myotis septentrionalis) during the maternity season in West Virginia (USA)

    Science.gov (United States)

    Johnson, J.B.; Edwards, J.W.; Ford, W.M.

    2011-01-01

    Nocturnal activity patterns of northern myotis (Myotis septentrionalis) at diurnal roost trees remain largely uninvestigated. For example, the influence of reproductive status, weather, and roost tree and surrounding habitat characteristics on timing of emergence, intra-night activity, and entrance at their roost trees is poorly known. We examined nocturnal activity patterns of northern myotis maternity colonies during pregnancy and lactation at diurnal roost trees situated in areas that were and were not subjected to recent prescribed fires at the Fernow Experimental Forest, West Virginia from 2007 to 2009. According to exit counts and acoustic data, northern myotis colony sizes were similar between reproductive periods and roost tree settings. However, intra-night activity patterns differed slightly between reproductive periods and roost trees in burned and non-burned areas. Weather variables poorly explained variation in activity patterns during pregnancy, but precipitation and temperature were negatively associated with activity patterns during lactation. ?? Museum and Institute of Zoology PAS.

  11. Ogun Oru: a traditional explanation for nocturnal neuropsychiatric disturbances among the Yoruba of Southwest Nigeria.

    Science.gov (United States)

    Aina, O F; Famuyiwa, O O

    2007-03-01

    This article describes three cases of ;ogun oru' (nocturnal warefare), a condition reported in southwest Nigeria involving an acute night-time disturbance that is culturally attributed to demonic infiltration of the body and psyche during dreaming. Ogun oru is characterized by its occurrence, a female preponderance, the perception of an underlying feud between the sufferer's earthly spouse and a ;spiritual' spouse, and the event of bewitchment through eating while dreaming. The condition is believed to be treatable through Christian prayers or elaborate traditional rituals designed to exorcise the imbibed demonic elements. Ogun oru may be a label applied to medical problems. The differential diagnosis includes mainly parasomnias, for example, sleep terror, sleepwalking and sleep paralysis and, to a lesser extent, nocturnal or sleep epilepsy.

  12. Perceived Discrimination and Nocturnal Blood Pressure Dipping Among Hispanics: The Influence of Social Support and Race.

    Science.gov (United States)

    Rodriguez, Carlos Jose; Gwathmey, TanYa M; Jin, Zhezhen; Schwartz, Joseph; Beech, Bettina M; Sacco, Ralph L; Di Tullio, Marco R; Homma, Shunichi

    2016-09-01

    Little is known about the relationship of perceived racism to ambulatory blood pressure (ABP) in Hispanics. We explored possible associations between ABP nocturnal dipping and perceived racism in a Hispanic cohort. Participants included 180 community-dwelling Hispanics from the Northern Manhattan Study. Measures included perceived racism, socioeconomic status, social support, and ABP monitoring. Nocturnal ABP nondipping was defined as a less than 10% decline in the average asleep systolic blood pressure relative to the awake systolic blood pressure. Overall, 77.8% of participants reported some form of perceived racism (Perceived Ethnic Discrimination Questionnaire scores >1.0). Greater social support was associated with less perceived discrimination (Spearman r = -0.54, p pressure levels during daytime exposures to discrimination.

  13. Visual and acoustic signaling in three species of Brazilian nocturnal tree frogs (Anura, Hylidae

    Directory of Open Access Journals (Sweden)

    Luís Felipe Toledo

    2007-06-01

    Full Text Available Visual communication seems to be widespread among nocturnal anurans, however, reports of these behaviors in many Neotropical species are lacking. Therefore, we gathered information collected during several sporadic field expeditions in central and southern Brazil with three nocturnal tree frogs: Aplastodiscus perviridis, Hypsiboas albopunctatus and H. bischoffi. These species displayed various aggressive behaviors, both visual and acoustic, towards other males. For A. perviridis we described arm lifting and leg kicking; for H. albopunctatus we described the advertisement and territorial calls, visual signalizations, including a previously unreported behavior (short leg kicking, and male-male combat; and for H. bischoffiwe described the advertisement and fighting calls, toes and fingers trembling, leg lifting, and leg kicking. We speculate about the evolution of some behaviors and concluded that the use of visual signals among Neotropical anurans may be much more common than suggested by the current knowledge.

  14. Increased sympathetic activity during sleep and nocturnal hypertension in Type 2 diabetic patients with diabetic nephropathy

    DEFF Research Database (Denmark)

    Nielsen, F S; Hansen, H P; Jacobsen, P

    1999-01-01

    AIMS: To elucidate the putative factors involved in the blunted nocturnal blood pressure reduction in hypertensive Type 2 diabetic patients with diabetic nephropathy. METHODS: Extracellular fluid volume and fluid shift from interstitial to plasma volume (haematocrit), sympathetic nervous activity...... (plasma noradrenaline and adrenaline) and the internal 'body clock' (serum melatonin) were investigated in 31 hypertensive Type 2 diabetes mellitus (DM) patients with diabetic nephropathy (24 males, age 60 (45-73) years). All variables, except extracellular volume, were measured repeatedly...... constant in both groups. Extracellular fluid volume and plasma melatonin levels were comparable in the two groups. CONCLUSION: Sustained adrenergic activity during sleep is associated with blunted nocturnal blood pressure reduction in hypertensive Type 2DM patients with diabetic nephropathy, probably...

  15. Depression of nocturnal pineal serotonin N-acetyltransferase activity in castrate male rats

    International Nuclear Information System (INIS)

    Rudeen, P.K.; Reiter, R.J.; Texas Univ., San Antonio

    1980-01-01

    Pineal serotonin N-acetyltransferase (NAT) activity was examined in intact rats, castrated rats, and in rats that had been castrated and had received testosterone proprionate. Castration resulted in significantly depressing nocturnal levels of pineal NAT (p<0.05) when compared to enzyme activity in intact rats. Testosterone proprionate administration restored plasma LH levels to normal values in castrate rats but did not induce nocturnal pineal enzyme activity to levels seen in the pineal glands of intact rats. The data substantiate the existence of a feedback control of pineal biosynthetic activity by the hypophyseal-gonadal system, but the identity of the hormone(s) responsible for regulation of pineal NAT activity is not known. (author)

  16. Choking at Night: A Case of Opercular Nocturnal Frontal Lobe Epilepsy

    Directory of Open Access Journals (Sweden)

    Geetanjali Rathore

    2013-01-01

    Full Text Available Frontal lobe seizures have a tendency to occur in sleep and in most cases occur exclusively insleep; these individuals are said to have nocturnal frontal lobe (NFLE. NFLE can be difficult to distinguish clinically from various other sleep disorders, particularly parasomnias, which also present with paroxysmal motor activity in sleep. Interictal and ictal EEG findings are frequently unremarkable or nonspecific in both parasomnias and NFLE making the diagnosis even more difficult. Nocturnal epilepsy should be suspected in patients with paroxysmal events at night characterized by high frequency, repetition, extrapyramidal features, and marked stereotypy of attacks. Here we present a 13-year-old female who was extensively worked up for choking episodes at night. On repeat video EEG she was found to have frontal opercular seizures. Once on Carbamazepine, her seizures completely resolved.

  17. Stable isotope analysis

    International Nuclear Information System (INIS)

    Tibari, Elghali; Taous, Fouad; Marah, Hamid

    2014-01-01

    This report presents results related to stable isotopes analysis carried out at the CNESTEN DASTE in Rabat (Morocco), on behalf of Senegal. These analyzes cover 127 samples. These results demonstrate that Oxygen-18 and Deuterium in water analysis were performed by infrared Laser spectroscopy using a LGR / DLT-100 with Autosampler. Also, the results are expressed in δ values (‰) relative to V-SMOW to ± 0.3 ‰ for oxygen-18 and ± 1 ‰ for deuterium.

  18. The effect of lateral decubitus position on nocturnal intraocular pressure over a habitual 24-hour period in healthy adults.

    Science.gov (United States)

    Hao, Jie; Zhen, Yi; Wang, Hao; Yang, Diya; Wang, Ningli

    2014-01-01

    To investigate the effect of lateral decubitus position (LDP) on nocturnal intraocular pressure (IOP) and the effect of LDP on 24-hour habitual IOP pattern in healthy subjects. Intraocular pressure was measured every 2-hours using an Accupen Applanation Tonometer (Accutome, USA). During the diurnal period (7:30 am, 9:30 am, 11:30 am, 1:30 pm, 3:30 pm, 5:30 pm, 7:30 pm, and 9:30 pm), IOP was measured in the sitting position under bright light (500-1000 lux) after the subjects had been seated for 5 min. The nocturnal IOP was measured in the supine position, right LDP, and left LDP, with randomized sequences, under dim light (hour habitual IOP patterns were obtained according to the nocturnal position (supine, right LDP and left LDP) for either eye. Phour period, the effect of LDP on habitual IOP pattern was not statistically significant, although the mean nocturnal IOP and the diurnal-nocturnal IOP change for the right and the left eye in the LDP pattern was slightly higher than that in the sitting-supine pattern. Significant nocturnal IOP differences existed between the dependent eye and the supine, but did not occur consistently for all time points. Over a 24-hour period, the effect of LDP on habitual IOP pattern was not statistically significant in healthy subjects.

  19. Signatures of functional constraint at aye-aye opsin genes: the potential of adaptive color vision in a nocturnal primate.

    Science.gov (United States)

    Perry, George H; Martin, Robert D; Verrelli, Brian C

    2007-09-01

    While color vision perception is thought to be adaptively correlated with foraging efficiency for diurnal mammals, those that forage exclusively at night may not need color vision nor have the capacity for it. Indeed, although the basic condition for mammals is dichromacy, diverse nocturnal mammals have only monochromatic vision, resulting from functional loss of the short-wavelength sensitive opsin gene. However, many nocturnal primates maintain intact two opsin genes and thus have dichromatic capacity. The evolutionary significance of this surprising observation has not yet been elucidated. We used a molecular population genetics approach to test evolutionary hypotheses for the two intact opsin genes of the fully nocturnal aye-aye (Daubentonia madagascariensis), a highly unusual and endangered Madagascar primate. No evidence of gene degradation in either opsin gene was observed for any of 8 aye-aye individuals examined. Furthermore, levels of nucleotide diversity for opsin gene functional sites were lower than those for 15 neutrally evolving intergenic regions (>25 kb in total), which is consistent with a history of purifying selection on aye-aye opsin genes. The most likely explanation for these findings is that dichromacy is advantageous for aye-ayes despite their nocturnal activity pattern. We speculate that dichromatic nocturnal primates may be able to perceive color while foraging under moonlight conditions, and suggest that behavioral and ecological comparisons among dichromatic and monochromatic nocturnal primates will help to elucidate the specific activities for which color vision perception is advantageous.

  20. The effect of dexlansoprazole MR on nocturnal heartburn and GERD-related sleep disturbances in patients with symptomatic GERD.

    Science.gov (United States)

    Fass, Ronnie; Johnson, David A; Orr, William C; Han, Cong; Mody, Reema; Stern, Kathleen N; Pilmer, Betsy L; Perez, M Claudia

    2011-03-01

    Nocturnal heartburn and related sleep disturbances are common among patients with gastroesophageal reflux disease (GERD). This study evaluated the efficacy of dexlansoprazole MR 30 mg in relieving nocturnal heartburn and GERD-related sleep disturbances, improving work productivity, and decreasing nocturnal symptom severity in patients with symptomatic GERD. Patients (N=305) with frequent, moderate-to-very severe nocturnal heartburn and associated sleep disturbances were randomized 1:1 in a double-blind fashion to receive dexlansoprazole MR or placebo once daily for 4 weeks. The primary end point was the percentage of nights without heartburn. Secondary end points were the percentage of patients with relief of nocturnal heartburn and of GERD-related sleep disturbances over the last 7 days of treatment. At baseline and week 4/final visit, patients completed questionnaires that assessed sleep quality, work productivity, and the severity and impact of nocturnal GERD symptoms. Dexlansoprazole MR 30 mg (n=152) was superior to placebo (n=153) in median percentage of nights without heartburn (73.1 vs. 35.7%, respectively; Pheartburn and GERD-related sleep disturbances (47.5 vs. 19.6%, 69.7 vs. 47.9%, respectively; Pheartburn, in reducing GERD-related sleep disturbances and the consequent impairments in work productivity, and in improving sleep quality/quality of life.

  1. Forensic Stable Isotope Biogeochemistry

    Science.gov (United States)

    Cerling, Thure E.; Barnette, Janet E.; Bowen, Gabriel J.; Chesson, Lesley A.; Ehleringer, James R.; Remien, Christopher H.; Shea, Patrick; Tipple, Brett J.; West, Jason B.

    2016-06-01

    Stable isotopes are being used for forensic science studies, with applications to both natural and manufactured products. In this review we discuss how scientific evidence can be used in the legal context and where the scientific progress of hypothesis revisions can be in tension with the legal expectations of widely used methods for measurements. Although this review is written in the context of US law, many of the considerations of scientific reproducibility and acceptance of relevant scientific data span other legal systems that might apply different legal principles and therefore reach different conclusions. Stable isotopes are used in legal situations for comparing samples for authenticity or evidentiary considerations, in understanding trade patterns of illegal materials, and in understanding the origins of unknown decedents. Isotope evidence is particularly useful when considered in the broad framework of physiochemical processes and in recognizing regional to global patterns found in many materials, including foods and food products, drugs, and humans. Stable isotopes considered in the larger spatial context add an important dimension to forensic science.

  2. Nocturnality constrains morphological and functional diversity in the eyes of reef fishes

    Directory of Open Access Journals (Sweden)

    Schmitz Lars

    2011-11-01

    Full Text Available Abstract Background Ambient light levels are often considered to drive the evolution of eye form and function. Diel activity pattern is the main mechanism controlling the visual environment of teleost reef fish, with day-active (diurnal fish active in well-illuminated conditions, whereas night-active (nocturnal fish cope with dim light. Physiological optics predicts several specific evolutionary responses to dim-light vision that should be reflected in visual performance features of the eye. Results We analyzed a large comparative dataset on morphological traits of the eyes in 265 species of teleost reef fish in 43 different families. The eye morphology of nocturnal reef teleosts is characterized by a syndrome that indicates better light sensitivity, including large relative eye size, high optical ratio and large, rounded pupils. Improved dim-light image formation comes at the cost of reduced depth of focus and reduction of potential accommodative lens movement. Diurnal teleost reef fish, released from the stringent functional requirements of dim-light vision have much higher morphological and optical diversity than nocturnal species, with large ranges of optical ratio, depth of focus, and lens accommodation. Conclusions Physical characteristics of the environment are an important factor in the evolution and diversification of the vertebrate eye. Both teleost reef fish and terrestrial amniotes meet the functional requirements of dim-light vision with a similar evolutionary response of morphological and optical modifications. The trade-off between improved dim-light vision and reduced optical diversity may be a key factor in explaining the lower trophic diversity of nocturnal reef teleosts.

  3. Diel turbidity cycles in a headwater stream: evidence of nocturnal bioturbation?

    OpenAIRE

    Cooper, Richard J.; Outram, Faye; Hiscock, Kevin M.

    2016-01-01

    Purpose: A small number of recent studies have linked daily cycles in stream turbidity to nocturnal bioturbation by aquatic fauna, principally crayfish, and demonstrated this process can significantly impact upon water quality under baseflow conditions. Adding to this limited body of research, we use high-resolution water quality monitoring data to investigate evidence of diel turbidity cycles in a lowland, headwater stream with a known signal crayfish (Pacifastacus leniusculus) population an...

  4. Report of a case of paroxysmal nocturnal hemoglobinuria (PNH) with complex evolution and liver transplant

    OpenAIRE

    Alencar,Railene Célia B.; Guimarães,Andréa M.; Brito Junior,Lacy C.

    2016-01-01

    ABSTRACT The paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired disease, with thrombotic episodes and frequent pancytopenia. We report the case of a 32 year-old female PNH patient with bone marrow aplasia, which followed a complex course, diagnosed with aplastic anemia associated with PNH, evolving in three years with Budd-Chiari syndrome and liver transplantation. Post-transplant complications, hepatic arterial thrombosis, graft rejection, liver retransplantation and treatment of P...

  5. Nocturnal blood pressure in normotensive subjects and those with white coat, primary, and secondary hypertension.

    OpenAIRE

    Middeke, M.; Schrader, J.

    1994-01-01

    OBJECTIVE--To compare the mean nocturnal blood pressure of patients with various forms of renal and endocrine hypertension with that in patients with primary and white coat hypertension, and normal blood pressure. DESIGN--Ambulatory monitoring of blood pressure over 24 hours in a prospective study. SETTING--Two German centres for outpatients with hypertension and kidney diseases. SUBJECTS--176 normotensive subjects, 490 patients with primary hypertension including mild and severe forms, 42 wi...

  6. Two new species of nocturnal bees of the genus Megalopta (Hymenoptera: Halictidae) with keys to species

    OpenAIRE

    Gonzalez, Victor H; Griswold, Terry; Ayala, Ricardo

    2010-01-01

    Megalopta Smith, 1853, is a Neotropical genus of nocturnal or crepuscular bees. Two subgenera are recognized with most of its nearly 30 species placed in the nominate subgenus. Species of Megalopta s. str. are more commonly collected than species of Noctoraptor Engel et al. 1997, all presumably parasites of Megalopta s. str. Two new species of Megalopta are described here: M. (Megalopta) tetewana, n. sp., from Mexico and M. (Noctoraptor) huaoranii, n. sp., from Ecuador. Identification keys to...

  7. Concealed by darkness: interactions between predatory bats and nocturnally migrating songbirds illuminated by DNA sequencing

    OpenAIRE

    Ibáñez, Carlos; Popa-Lisseanu, Ana G.; Pastor-Beviá, David; García-Mudarra, Juan L.; Juste, Javier

    2016-01-01

    Recently, several species of aerial-hawking bats have been found to prey on migrating songbirds, but details on this behaviour and its relevance for bird migration are still unclear. We sequenced avian DNA in feather-containing scats of the bird-feeding bat Nyctalus lasiopterus from Spain collected during bird migration seasons. We found very high prey diversity, with 31 bird species from eight families of Passeriformes, almost all of which were nocturnally flying sub-Saharan migrants. Moreov...

  8. Nocturia in men is a chaotic condition dominated by nocturnal polyuria.

    Science.gov (United States)

    Fujimura, Tetsuya; Yamada, Yuta; Sugihara, Toru; Azuma, Takeshi; Suzuki, Motofumi; Fukuhara, Hiroshi; Nakagawa, Tohru; Kume, Haruki; Igawa, Yasuhiko; Homma, Yukio

    2015-05-01

    To characterize nocturia in men based on frequency volume chart data and symptom profiles assessed using the Core Lower Urinary Tract Symptom Score and Athens Insomnia Scale questionnaires. The Core Lower Urinary Tract Symptom Score and Athens Insomnia Scale questionnaires were administered to 299 consecutive treatment naïve men with nocturia (≥one time per night). Frequency volume chart data were recorded for 2 days. Correlations between nocturia and clinical characteristics including symptom scores, clinical diagnosis, Charlson Comorbidity Index, estimated glomerular filtration rate, uroflowmetry and prostate volume were analyzed. Patients were divided into five groups: one time (n = 36), two times (n = 65), three times (n = 85), four times (n = 78) and five times (n = 34) of nocturia. Age, prevalence or severity of chronic kidney disease, hyperlipidemia, low bladder capacity, nocturnal polyuria, urgency, bladder pain and sleep disorders were significantly correlated with the severity of nocturia. The Spearman correlation analysis identified eight possible independent factors for nocturia: age, estimated glomerular filtration rate, urgency, bladder pain, sleep quality, sleepiness during the day, average voided volume and nocturnal volume divided by body weight. Logistic regression analysis showed that nocturnal volume divided by body weight was the strongest factor of nocturia, and ≥7, 9 and 9.7 mL/kg were practical cut-off values of three, four and five times per night of nocturia, respectively. Nocturia in men is a chaotic condition dominated by nocturnal polyuria, and related to multiple factors including age, renal function, urgency, bladder pain, insomnia and bladder volume. © 2015 The Japanese Urological Association.

  9. α(1)-adrenoceptor blocker naftopidil improves sleep disturbance with reduction in nocturnal urine volume.

    Science.gov (United States)

    Yokoyama, Osamu; Aoki, Yoshitaka; Tsujimura, Akira; Takao, Tetsuya; Namiki, Mikio; Okuyama, Akihiko

    2011-04-01

    To examine the mechanism underlying improvements in nocturia by α(1)-blockers, we investigated whether the α(1)-blocker naftopidil acts on nocturia with sleep disturbance using a frequency/volume chart (FVC). A total of 56 male patients with lower urinary tract symptoms were enrolled. The inclusion criteria were as follows: eight or more points on the I-PSS; three or more points on the I-PSS score for nocturia; and prostate volume larger than 20 ml. Patients received 50 mg of naftopidil once daily for 4 weeks, and non-responders received 75 mg for another 4 weeks. All patients were examined, and their data entered into FVC for 2 days before and after administration of naftopidil. Quality of sleep was also evaluated using modified Pittsburgh sleep quality index (PSQI). Patients with sleep quality scores of three or four were assigned to sleep disturbance group (n = 33), while those with scores of less than three were assigned to non-disturbance group (n = 23). After administration of naftopidil, total I-PSS decreased and nocturia score decreased from 3.5 to 2.6 (P < 0.01). Total mean score of modified PSQI in sleep disturbance group became significantly lower after administration of naftopidil (from 16.9 to 14.0; P < 0.01). Naftopidil significantly decreased nocturnal urine volume, resulting in a decrease in the nocturnal polyuria index in both sleep disturbance and non-disturbance groups. These results suggest that α(1)-blockers have the ability to normalize sleep disorders. Naftopidil improved nocturnal polyuria regardless of the presence of sleep disturbance, meaning that it might directly reduce nocturnal urine production.

  10. Factors affecting nocturnal enuresis amongst school-aged children: brief report

    OpenAIRE

    Ashrafalsadat Hakim; Farshid Kompani; Mohammad Bahadoram

    2015-01-01

    Enuresis is the inability to control urination during sleep. It is one of the most common childhood urologic disorders. Nocturnal enuresis refers to the occurrence of involuntary voiding at night after 5 years. Persistent nocturia can decrease self-esteem, increase anxiety and other emotional problems in children. The aim of this study is to evaluate the factors affecting nocturia amongst school-aged children. Methods: This cross- sectional study was conducted on 200 children over a period...

  11. Nocturnality in synapsids predates the origin of mammals by over 100 million years

    OpenAIRE

    Angielczyk, K. D.; Schmitz, L.

    2014-01-01

    Nocturnality is widespread among extant mammals and often considered the ancestral behavioural pattern for all mammals. However, mammals are nested within a larger clade, Synapsida, and non-mammalian synapsids comprise a rich phylogenetic, morphological and ecological diversity. Even though non-mammalian synapsids potentially could elucidate the early evolution of diel activity patterns and enrich the understanding of synapsid palaeobiology, data on their diel activity are currently unavailab...

  12. Seeing in the dark: vision and visual behaviour in nocturnal bees and wasps.

    Science.gov (United States)

    Warrant, Eric J

    2008-06-01

    In response to the pressures of predation, parasitism and competition for limited resources, several groups of (mainly) tropical bees and wasps have independently evolved a nocturnal lifestyle. Like their day-active (diurnal) relatives, these insects possess apposition compound eyes, a relatively light-insensitive eye design that is best suited to vision in bright light. Despite this, nocturnal bees and wasps are able to forage at night, with many species capable of flying through a dark and complex forest between the nest and a foraging site, a behaviour that relies heavily on vision and is limited by light intensity. In the two best-studied species - the Central American sweat bee Megalopta genalis (Halictidae) and the Indian carpenter bee Xylocopa tranquebarica (Apidae) - learned visual landmarks are used to guide foraging and homing. Their apposition eyes, however, have only around 30 times greater optical sensitivity than the eyes of their closest diurnal relatives, a fact that is apparently inconsistent with their remarkable nocturnal visual abilities. Moreover, signals generated in the photoreceptors, even though amplified by a high transduction gain, are too noisy and slow to transmit significant amounts of information in dim light. How have nocturnal bees and wasps resolved these paradoxes? Even though this question remains to be answered conclusively, a mounting body of theoretical and experimental evidence suggests that the slow and noisy visual signals generated by the photoreceptors are spatially summed by second-order monopolar cells in the lamina, a process that could dramatically improve visual reliability for the coarser and slower features of the visual world at night.

  13. Is Nocturnal Foraging in a Tropical Bee an Escape From Interference Competition?

    OpenAIRE

    Smith, Adam R.; Kitchen, Shannon M.; Toney, Ryan M.; Ziegler, Christian

    2017-01-01

    Temporal niche partitioning may result from interference competition if animals shift their activity patterns to avoid aggressive competitors. If doing so also shifts food sources, it is difficult to distinguish the effects of interference and consumptive competition in selecting for temporal niche shift. Bees compete for pollen and nectar from flowers through both interference and consumptive competition, and some species of bees have evolved nocturnality. Here, we use tropical forest canopy...

  14. How does a diurnal hawkmoth find nectar? Differences in sensory control with a nocturnal relative

    OpenAIRE

    Joaquín Goyret; Almut Kelber

    2011-01-01

    Recent research shows that a nocturnal hawkmoth, Manduca sexta, inspects flowers in search for nectar by means of a series of hovering and proboscis movements controlled by different sensory modalities, mainly vision and mechanoreception. The diurnal Macroglossum stellatarum is a closely related hawkmoth challenged with the same task but under illuminances 6--8 orders of magnitude higher. Here, we use flower models presenting color markings, 3D features, or both to study innate flower movemen...

  15. Olfactory recognition of predators by nocturnal lizards: safety outweighs thermal benefits

    OpenAIRE

    Jonathan K. Webb; David A. Pike; Richard Shine

    2009-01-01

    Many prey species are faced with multiple predators that differ in the degree of danger posed. The threat-sensitive predator avoidance hypothesis predicts that prey should assess the degree of threat posed by different predators and match their behavior according to current levels of risk. To test this prediction, we compared the behavioral responses of nocturnal velvet geckos, Oedura lesueurii, to chemicals from 2 snakes that pose different threats: the dangerous broad-headed snake Hoploceph...

  16. Tax Unit Boundaries

    Data.gov (United States)

    Kansas Data Access and Support Center — The Statewide GIS Tax Unit boundary file was created through a collaborative partnership between the State of Kansas Department of Revenue Property Valuation...

  17. 500 Cities: City Boundaries

    Data.gov (United States)

    U.S. Department of Health & Human Services — This city boundary shapefile was extracted from Esri Data and Maps for ArcGIS 2014 - U.S. Populated Place Areas. This shapefile can be joined to 500 Cities...

  18. National Forest Boundaries

    Data.gov (United States)

    Minnesota Department of Natural Resources — This theme shows the USFS national forest boundaries in the state. This data was acquired from the GIS coordinators at both the Chippewa National Forest and the...

  19. Allegheny County Parcel Boundaries

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains parcel boundaries attributed with county block and lot number. Use the Property Information Extractor for more control downloading a filtered...

  20. Boundary representation modelling techniques

    CERN Document Server

    2006-01-01

    Provides the most complete presentation of boundary representation solid modelling yet publishedOffers basic reference information for software developers, application developers and users Includes a historical perspective as well as giving a background for modern research.

  1. NM School District Boundaries

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The dataset represents the boundaries of all public school districts in the state of New Mexico. The source for the data layer is the New Mexico Public Education...

  2. Site Area Boundaries

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset consists of site boundaries from multiple Superfund sites in U.S. EPA Region 8. These data were acquired from multiple sources at different times and...

  3. HUC 8 Boundaries

    Data.gov (United States)

    Kansas Data Access and Support Center — This data set is a digital hydrologic unit boundary that is at the 4-digit, 6-digit, 8-digit, and 11-digit level. The data set was developed by delineating the...

  4. State Park Statutory Boundaries

    Data.gov (United States)

    Minnesota Department of Natural Resources — Legislative statutory boundaries for sixty six state parks, six state recreation areas, and eight state waysides. These data are derived principally from DNR's...

  5. Nocturnal Wakefulness is Associated with Next-Day Suicidal Ideation in Major Depression and Bipolar Disorder

    Science.gov (United States)

    Ballard, Elizabeth D.; Vande Voort, Jennifer L.; Bernert, Rebecca A.; Luckenbaugh, David A.; Richards, Erica M.; Niciu, Mark J.; Furey, Maura L.; Duncan, Wallace C.; Zarate, Carlos A.

    2016-01-01

    Objective Self-reported sleep disturbances may confer elevated risk for suicidal ideation, suicide attempts, and death. However, limited research has evaluated polysomnography (PSG)-determined sleep disturbance as an acute physiological risk factor for suicidal thoughts. This study sought to investigate the relationship between nocturnal wakefulness in association with next-day suicidal ideation using overnight PSG assessment from data collected between 2006 and 2013. Method Participants with DSM-IV-diagnosed major depressive disorder (MDD) or bipolar depression underwent overnight PSG monitoring in a sleep laboratory. The Hamilton Depression Rating Scale (HAM-D) was administered the morning after PSG recording to assess next-day suicidal ideation, severity of depressive symptoms, and subjective sleep disturbances. Results Using a generalized linear mixed model, a significant time-by-ideation interaction was found indicating greater nocturnal wakefulness at 4:00 AM among participants with suicidal ideation (F(4,136) = 3.65, p = .007). Increased time awake during the 4:00 AM hour (4:00 to 4:59) was significantly associated with elevated suicidal thoughts the next day (standardized β = .31, p = .008). This relationship persisted after controlling for age, gender, diagnosis, and severity of depressive symptoms. Conclusion Greater nocturnal wakefulness, particularly in the early morning hours, was significantly associated with next-day suicidal thoughts. PSG-documented sleep disruption at specific times of night may represent an acute risk factor of suicidal ideation that warrants additional research. Clinical Trials Identifier NCT00024635 PMID:27337418

  6. A nocturnal decline of salivary pH associated with airway hyperresponsiveness in asthma.

    Science.gov (United States)

    Watanabe, Masanari; Sano, Hiroyuki; Tomita, Katsuyuki; Yamasaki, Akira; Kurai, Jun; Hasegawa, Yasuyuki; Igishi, Tadashi; Okazaki, Ryota; Tohda, Yuji; Burioka, Naoto; Shimizu, Eiji

    2010-08-01

    Salivary pH is associated with esophageal acid reflux and neutralization of esophageal acid. In this study, we assessed the association between nocturnal decline of salivary pH and airway hyperresponsiveness. Salivary pH was serially assessed in 9 patients with mild asthma (7 men and 2 women; mean age 33.3 years; mean %predicted FEV(1.0) 89.4%) and 10 healthy volunteers (6 men and 4 women; mean age 31.2 years) using a pH indicator tape. The buffering capacity of saliva was defined as the median effective dose (ED(50)) for acidification of saliva with 0.01 N HCl, and airway responsiveness was defined as the dose of methacholine producing a 35% fall in Grs (PD(35)-Grs). There was a significant correlation between the values obtained from the pH indicator tape and those obtained from the electrometric pH meter. Using the indicator tape for sequential monitoring, we observed a nocturnal fall (ΔpH) in salivary pH in all subjects. A significant correlation was found between airway hyperresponsiveness (PD(35)-Grs) and either ΔpH or ED(50) in mildly asthmatic patients. Vagal reflux dysfunction might contribute to nocturnal salivary pH as well as to airway hyperresponsiveness in mild asthmatics.

  7. Nocturnal to Diurnal Switches with Spontaneous Suppression of Wheel-Running Behavior in a Subterranean Rodent

    Science.gov (United States)

    Tachinardi, Patricia; Tøien, Øivind; Valentinuzzi, Veronica S.; Buck, C. Loren; Oda, Gisele A.

    2015-01-01

    Several rodent species that are diurnal in the field become nocturnal in the lab. It has been suggested that the use of running-wheels in the lab might contribute to this timing switch. This proposition is based on studies that indicate feed-back of vigorous wheel-running on the period and phase of circadian clocks that time daily activity rhythms. Tuco-tucos (Ctenomys aff. knighti) are subterranean rodents that are diurnal in the field but are robustly nocturnal in laboratory, with or without access to running wheels. We assessed their energy metabolism by continuously and simultaneously monitoring rates of oxygen consumption, body temperature, general motor and wheel running activity for several days in the presence and absence of wheels. Surprisingly, some individuals spontaneously suppressed running-wheel activity and switched to diurnality in the respirometry chamber, whereas the remaining animals continued to be nocturnal even after wheel removal. This is the first report of timing switches that occur with spontaneous wheel-running suppression and which are not replicated by removal of the wheel. PMID:26460828

  8. Intermittent nocturnal hypoxia and metabolic risk in obese adolescents with obstructive sleep apnea.

    Science.gov (United States)

    Narang, Indra; McCrindle, Brian W; Manlhiot, Cedric; Lu, Zihang; Al-Saleh, Suhail; Birken, Catherine S; Hamilton, Jill

    2018-01-22

    There is conflicting data regarding the independent associations of obstructive sleep apnea (OSA) with metabolic risk in obese youth. Previous studies have not consistently addressed central adiposity, specifically elevated waist to height ratio (WHtR), which is associated with metabolic risk independent of body mass index. The objective of this study was to determine the independent effects of the obstructive apnea-hypopnea index (OAHI) and associated indices of nocturnal hypoxia on metabolic function in obese youth after adjusting for WHtR. Subjects had standardized anthropometric measurements. Fasting blood included insulin, glucose, glycated hemoglobin, alanine transferase, and aspartate transaminase. Insulin resistance was quantified with the homeostatic model assessment. Overnight polysomnography determined the OAHI and nocturnal oxygenation indices. Of the 75 recruited subjects, 23% were diagnosed with OSA. Adjusting for age, gender, and WHtR in multivariable linear regression models, a higher oxygen desaturation index was associated with a higher fasting insulin (coefficient [standard error] = 48.076 [11.255], p Intermittent nocturnal hypoxia rather than the OAHI was associated with metabolic risk in obese youth after adjusting for WHtR. Measures of abdominal adiposity such as WHtR should be considered in future studies that evaluate the impact of OSA on metabolic health.

  9. Adaptation to Life in the High Andes: Nocturnal Oxyhemoglobin Saturation in Early Development.

    Science.gov (United States)

    Hill, Catherine Mary; Baya, Ana; Gavlak, Johanna; Carroll, Annette; Heathcote, Kate; Dimitriou, Dagmara; L'Esperance, Veline; Webster, Rebecca; Holloway, John; Virues-Ortega, Javier; Kirkham, Fenella Jane; Bucks, Romola Starr; Hogan, Alexandra Marie

    2016-05-01

    Physiological adaptation to high altitude hypoxia may be impaired in Andeans with significant European ancestry. The respiratory 'burden' of sleep may challenge adaptation, leading to relative nocturnal hypoxia. Developmental aspects of sleep-related breathing in high-altitude native children have not previously been reported. We aimed to determine the influence of development on diurnal-nocturnal oxyhemoglobin differences in children living at high altitude. This was a cross-sectional, observational study. Seventy-five healthy Bolivian children aged 6 mo to 17 y, native to low altitude (500 m), moderate high altitude (2,500 m), and high altitude (3,700 m) were recruited. Daytime resting pulse oximetry was compared to overnight recordings using Masimo radical oximeters. Genetic ancestry was determined from DNA samples. Children had mixed European/Amerindian ancestry, with no significant differences between altitudes. Sixty-two participants had ≥ 5 h of nocturnal, artifact-free data. As predicted, diurnal mean oxyhemoglobin saturation decreased across altitudes (infants and children, both P sleep-related hypoxia in early childhood has potential lifespan implications. Future studies should characterize the sleep- related respiratory physiology underpinning our observations. © 2016 Associated Professional Sleep Societies, LLC.

  10. Nocturnal to Diurnal Switches with Spontaneous Suppression of Wheel-Running Behavior in a Subterranean Rodent.

    Directory of Open Access Journals (Sweden)

    Patricia Tachinardi

    Full Text Available Several rodent species that are diurnal in the field become nocturnal in the lab. It has been suggested that the use of running-wheels in the lab might contribute to this timing switch. This proposition is based on studies that indicate feed-back of vigorous wheel-running on the period and phase of circadian clocks that time daily activity rhythms. Tuco-tucos (Ctenomys aff. knighti are subterranean rodents that are diurnal in the field but are robustly nocturnal in laboratory, with or without access to running wheels. We assessed their energy metabolism by continuously and simultaneously monitoring rates of oxygen consumption, body temperature, general motor and wheel running activity for several days in the presence and absence of wheels. Surprisingly, some individuals spontaneously suppressed running-wheel activity and switched to diurnality in the respirometry chamber, whereas the remaining animals continued to be nocturnal even after wheel removal. This is the first report of timing switches that occur with spontaneous wheel-running suppression and which are not replicated by removal of the wheel.

  11. Noninvasive imaging of brain oxygen metabolism in children with primary nocturnal enuresis during natural sleep.

    Science.gov (United States)

    Yu, Bing; Huang, Mingzhu; Zhang, Xu; Ma, Hongwei; Peng, Miao; Guo, Qiyong

    2017-05-01

    A series of studies have revealed that nocturnal enuresis is closely related to hypoxia in children with primary nocturnal enuresis (PNE). However, brain oxygen metabolism of PNE children has not been investigated before. The purpose of this study was to investigate changes in whole-brain cerebral metabolic rate of oxygen (CMRO 2 ), cerebral blood flow (CBF), and oxygen extraction fraction (OEF) in children suffering from PNE. We used the newly developed T2-relaxation-under-spin-tagging (TRUST) magnetic resonance imaging technique. Neurological evaluation, structural imaging, phase-contrast, and the TRUST imaging method were applied in children with PNE (n = 37) and healthy age- and sex-matched control volunteers (n = 39) during natural sleep to assess whole-brain CMRO 2 , CBF, OEF, and arousal from sleep scores. Results showed that whole-brain CMRO 2 and OEF values of PNE children were higher in controls, while there was no significant difference in CBF. Consequently, OEF levels of PNE children were increased to maintain oxygen supply. The elevation of OEF was positively correlated with the difficulty of arousal. Our results provide the first evidence that high oxygen consumption and high OEF values could make PNE children more susceptible to hypoxia, which may induce cumulative arousal deficits and make them more prone to nocturnal enuresis. Hum Brain Mapp 38:2532-2539, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  12. Navigational efficiency of nocturnal Myrmecia ants suffers at low light levels.

    Directory of Open Access Journals (Sweden)

    Ajay Narendra

    Full Text Available Insects face the challenge of navigating to specific goals in both bright sun-lit and dim-lit environments. Both diurnal and nocturnal insects use quite similar navigation strategies. This is despite the signal-to-noise ratio of the navigational cues being poor at low light conditions. To better understand the evolution of nocturnal life, we investigated the navigational efficiency of a nocturnal ant, Myrmecia pyriformis, at different light levels. Workers of M. pyriformis leave the nest individually in a narrow light-window in the evening twilight to forage on nest-specific Eucalyptus trees. The majority of foragers return to the nest in the morning twilight, while few attempt to return to the nest throughout the night. We found that as light levels dropped, ants paused for longer, walked more slowly, the success in finding the nest reduced and their paths became less straight. We found that in both bright and dark conditions ants relied predominantly on visual landmark information for navigation and that landmark guidance became less reliable at low light conditions. It is perhaps due to the poor navigational efficiency at low light levels that the majority of foragers restrict navigational tasks to the twilight periods, where sufficient navigational information is still available.

  13. Sleep disorders and the prevalence of asymptomatic nocturnal acid and non-acid reflux.

    Science.gov (United States)

    Herdman, Christine; Marzio, Dina Halegoua-De; Shah, Paurush; Denuna-Rivera, Susie; Doghramji, Karl; Cohen, Sidney; Dimarino, Anthony J

    2013-01-01

    Nocturnal acid reflux is associated with symptomatic and asymptomatic sleep arousals, leading to fragmented sleep. The frequency and influence of acid reflux in patients with various forms of insomnia has not been reported. The aim of this study was to quantify nocturnal acid and nonacid reflux in patients with primary sleep disorders as previously diagnosed by polysomnography. THIRTY ONE SUBJECTS WERE STUDIED: (A) 9 subjects with a polysomnographically diagnosed sleep disorder (1 with restless legs syndrome, 4 with narcolepsy, 4 with periodic limb movement disorder); (B) 12 subjects with primary insomnia (PI) and unrevealing polysomnography; and (C) 10 controls without disturbed sleep. All subjects underwent a physical examination and 24 h transnasal pH and impedance monitoring to detect acid and non-acid reflux. The 21 subjects with fragmented sleep due to a primary sleep disorder had significantly more recumbent acid exposure (>1.2% of time) as compared with control subjects (33% versus 0%). When fragmented sleep subjects were divided into two groups, 17% of PI subjects and 55% of subjects with a diagnosed sleep disorder had significant recumbent acid exposure (P=0.009). Likewise, the median recumbent nonacid events were increased in the sleep disordered group (P=0.011). This study indicates that patients with primary sleep disorders have prominent nocturnal acid reflux without symptoms of daytime acid reflux. Acid reflux is most prominent in patients with polysomnographic findings of disturbed sleep as compared to patients with PI; while non acid reflux is increased minimally in these patients.

  14. Nocturnal uptake and assimilation of nitrogen dioxide by C3 and CAM plants.

    Science.gov (United States)

    Takahashi, Misa; Konaka, Daisuke; Sakamoto, Atsushi; Morikawa, Hiromichi

    2005-01-01

    In order to investigate nocturnal uptake and assimilation of NO2 by C3 and crassulacean acid metabolism (CAM) plants, they were fumigated with 4 microl l(-1) 15N-labeled nitrogen dioxide (NO2) for 8 h. The amount of NO2 and assimilation of NO2 by plants were determined by mass spectrometry and Kjeldahl-nitrogen based mass spectrometry, respectively. C3 plants such as kenaf (Hibiscus cannabinus), tobacco (Nicotiana tabacum) and ground cherry (Physalis alkekengi) showed a high uptake and assimilation during daytime as high as 1100 to 2700 ng N mg(-1) dry weight. While tobacco and ground cherry strongly reduced uptake and assimilation of NO2 during nighttime, kenaf kept high nocturnal uptake and assimilation of NO2 as high as about 1500 ng N mg(-1) dry weight. Stomatal conductance measurements indicated that there were no significant differences to account for the differences in the uptake of NO2 by tobacco and kenaf during nighttime. CAM plants such as Sedum sp., Kalanchoe blossfeldiana (kalanchoe) and Aloe arborescens exhibited nocturnal uptake and assimilation of NO2. However, the values of uptake and assimilation of NO2 both during daytime and nighttime was very low (at most about 500 ng N mg(-1) dry weight) as compared with those of above mentioned C3 plants. The present findings indicate that kenaf is an efficient phytoremediator of NO2 both during daytime and nighttime.

  15. Association between morphometric variables and nocturnal desaturation in sickle-cell anemia.

    Science.gov (United States)

    Salles, Cristina; Bispo, Marcelo; Trindade-Ramos, Regina Terse

    2014-01-01

    to evaluate associations between morphometric variables, cervical circumference (CC), and abdominal circumference (AC) with the presence of nocturnal desaturation in children and adolescents with sickle-cell anemia. all patients were submitted to baseline polysomnography, oral cavity measurements (maxillary intermolar distance, mandibular intermolar distance, and overjet), and CC and AC measurements. a total of 85 patients were evaluated. A positive correlation was observed between the height/age Z-score and CC measurement (r = 0.233, p = 0.031). The presence of nocturnal desaturation was associated with CC (59.2± 9.3 vs. 67.5 ± 10.7, p = 0.006) and AC measurements (27.0 ± 2.0 vs. 29.0± 2.1, p = 0.028). There was a negative correlation between desaturation and maxillary intermolar distance (r = -0.365, p = 0.001) and mandibular intermolar distance (r = -0.233, p = 0.037). the morphometric variables of CC and AC may contribute to raise suspicion of nocturnal desaturation in children and adolescents with sickle-cell anemia. Copyright © 2014 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  16. Association between morphometric variables and nocturnal desaturation in sickle-cell anemia

    Directory of Open Access Journals (Sweden)

    Cristina Salles

    2014-07-01

    Full Text Available OBJECTIVE: to evaluate associations between morphometric variables, cervical circumference (CC, and abdominal circumference (AC with the presence of nocturnal desaturation in children and adolescents with sickle-cell anemia. METHODS: all patients were submitted to baseline polysomnography, oral cavity measurements (maxillary intermolar distance, mandibular intermolar distance, and overjet, and CC and AC measurements. RESULTS: a total of 85 patients were evaluated. A positive correlation was observed between the height/age Z-score and CC measurement (r = 0.233, p = 0.031. The presence of nocturnal desaturation was associated with CC (59.2± 9.3 vs. 67.5 ± 10.7, p = 0.006 and AC measurements (27.0 ± 2.0 vs. 29.0± 2.1, p = 0.028. There was a negative correlation between desaturation and maxillary intermolar distance (r = -0.365, p = 0.001 and mandibular intermolar distance (r = -0.233, p = 0.037. CONCLUSIONS: the morphometric variables of CC and AC may contribute to raise suspicion of nocturnal desaturation in children and adolescents with sickle-cell anemia.

  17. Entropy Stability and the No-Slip Wall Boundary Condition

    KAUST Repository

    Svä rd, Magnus; Carpenter, Mark H.; Parsani, Matteo

    2018-01-01

    We present an entropy stable numerical scheme subject to no-slip wall boundary conditions. To enforce entropy stability only the no-penetration boundary condition and a temperature condition are needed at a wall, and this leads to an L bound on the conservative variables. In this article, we take the next step and design a finite difference scheme that also bounds the velocity gradients. This necessitates the use of the full no-slip conditions.

  18. Entropy Stability and the No-Slip Wall Boundary Condition

    KAUST Repository

    Svärd, Magnus

    2018-01-18

    We present an entropy stable numerical scheme subject to no-slip wall boundary conditions. To enforce entropy stability only the no-penetration boundary condition and a temperature condition are needed at a wall, and this leads to an L bound on the conservative variables. In this article, we take the next step and design a finite difference scheme that also bounds the velocity gradients. This necessitates the use of the full no-slip conditions.

  19. Entropy Stable Summation-by-Parts Formulations for Compressible Computational Fluid Dynamics

    KAUST Repository

    Carpenter, M.H.; Fisher, T.C.; Nielsen, E.J.; Parsani, Matteo; Svä rd, M.; Yamaleev, N.

    2016-01-01

    that ensure conservation, accuracy and preserve the interior entropy estimates. Nonlinearly stable solid wall boundary conditions are also available. Existing SBP operators that lack a stability proof (e.g. weighted essentially nonoscillatory) may be combined

  20. The Australian Bogong Moth Agrotis infusa: A Long-Distance Nocturnal Navigator

    Directory of Open Access Journals (Sweden)

    Eric Warrant

    2016-04-01

    Full Text Available The nocturnal Bogong moth (Agrotis infusa is an iconic and well-known Australian insect that is also a remarkable nocturnal navigator. Like the Monarch butterflies of North America, Bogong moths make a yearly migration over enormous distances, from southern Queensland, western and northwestern New South Wales (NSW and western Victoria, to the alpine regions of NSW and Victoria. After emerging from their pupae in early spring, adult Bogong moths embark on a long nocturnal journey towards the Australian Alps, a journey that can take many days or even weeks and cover over 1000 km. Once in the Alps (from the end of September, Bogong moths seek out the shelter of selected and isolated high ridge-top caves and rock crevices (typically at elevations above 1800 m. In hundreds of thousands, moths line the interior walls of these cool alpine caves where they “hibernate” over the summer months (referred to as “estivation”. Towards the end of the summer (February and March, the same individuals that arrived months earlier leave the caves and begin their long return trip to their breeding grounds. Once there, moths mate, lay eggs and die. The moths that hatch in the following spring then repeat the migratory cycle afresh. Despite having had no previous experience of the migratory route, these moths find their way to the Alps and locate their estivation caves that are dotted along the high alpine ridges of southeastern Australia. How naïve moths manage this remarkable migratory feat still remains a mystery, although there are many potential sensory cues along the migratory route that moths might rely on during their journey, including visual, olfactory, mechanical and magnetic cues. Here we review our current knowledge of the Bogong moth, including its natural history, its ecology, its cultural importance to the Australian Aborigines and what we understand about the sensory basis of its long-distance nocturnal migration. From this analysis it becomes

  1. Screening and managing obstructive sleep apnoea in nocturnal heart block patients: an observational study.

    Science.gov (United States)

    Wu, Xu; Liu, Zilong; Chang, Su Chi; Fu, Cuiping; Li, Wenjing; Jiang, Hong; Jiang, Liyan; Li, Shanqun

    2016-02-16

    Nocturnal heart block often occurs in patients with obstructive sleep apnoea (OSA). It is more likely to be undiagnosed in heart block patients who are ignorant of the symptoms of sleep disorder. Berlin Questionnaire (BQ) is a highly reliable way to discover the risk factors of OSA, whereas the validity in sleep-related heart block patients is uncertain. We performed an observational study to address these issues and confirmed the potential protective effect of continuous positive airway pressure (CPAP). Patients who were previously diagnosed with nocturnal heart block with R-R pauses exceeding 2 seconds were retrospective screened from the ECG centre of Zhongshan hospital. These recruited participants completed Berlin Questionnaire and underwent polysomnography synchronously with 24-hour Holter monitoring. A cross-sectional analysis was performed to confirm the association between nocturnal arrhythmia and OSA, as well as to assess the diagnostic accuracy of the BQ. Subsequently, subjects diagnosed with OSA (apnoea-hypopnoea index > 5) underwent 3 consecutive days of CPAP therapy. On the third day, patients repeated 24-hour Holter monitoring within the institution of CPAP. The symptoms of disruptive snoring and hypersomnolence in 72 enrolled patients were more related to the occurrence of nocturnal heart block (r = 0.306, 0.226, respectively, p = 0.015, 0.019) than syncope (r = 0.134, p = 0.282) and palpitations (r = 0.106, p = 0.119), which were prominent trait of our study population. The sensitivity, specificity, positive and negative predictive value of the BQ at a cut-off point of 5 of AHI for detecting OSA in heart block patients was 81.0 %, 44.4 %, 91.07 % and 25 %. Nocturnal heart block does not appear to occur exclusively in severe sleep apnoea. The frequent occurrence of arrhythmias in prominent oxygen desaturation supports the correlation between them. CPAP therapy resulted in significant decrease in the average number of

  2. On concentration footprints for a tall tower in the presence of a nocturnal low-level jet

    DEFF Research Database (Denmark)

    Sogachev, Andrey; Leclerc, M.Y.

    2011-01-01

    contribution area shifts during the night depending on the wind direction at the sensor location, a feature most prominent in the presence of decoupling between sensor levels and surface sources. Simulations suggest that atmospheric static stability alone is not a sufficient criterion to trigger flow......This paper reports on the location of sources contributing to a point concentration measurement in the stable boundary layer. Concentration footprints for sensors located at different heights during the night are examined using a backward-in-time Lagrangian stochastic dispersion model. Simulations...

  3. Grain boundary structure and properties

    International Nuclear Information System (INIS)

    Balluffi, R.W.

    1979-01-01

    An attempt is made to distinguish those fundamental aspects of grain boundaries which should be relevant to the problem of the time dependent fracture of high temperature structural materials. These include the basic phenomena which are thought to be associated with cavitation and cracking at grain boundaries during service and with the more general microstructural changes which occur during both processing and service. A very brief discussion of the current state of our knowledge of these fundamentals is given. Included are the following: (1) structure of ideal perfect boundaries; (2) defect structure of grain boundaries; (3) diffusion at grain boundaries; (4) grain boundaries as sources/sinks for point defects; (5) grain boundary migration; (6) dislocation phenomena at grain boundaries; (7) atomic bonding and cohesion at grain boundaries; (8) non-equilibrium properties of grain boundaries; and (9) techniques for studying grain boundaries

  4. Dynamical simulation of structural multiplicity in grain boundaries

    International Nuclear Information System (INIS)

    Majid, I.; Bristowe, P.D.

    1987-06-01

    Work on a computer simulation study of a low-energy high-angle boundary structure which is not periodic have been recently reported. This result is of interest since grain boundary structures are usually assumed to have a periodicity corresponding to the appropriate coincidence site lattice (CSL) and many experimental observations of the structure of grain boundaries performed using conventional and high-resolution electron microscopy, electron diffraction and x-ray diffraction appear to support this work. However, this work, using empirical interatomic pair potentials and the relaxation method of molecular statics, have simulated a Σ = 5 36.87 0 (001) twist boundary and found a low energy structure having a larger repeat cell than the CSL and is composed of two different types of structural unit that are randomly distributed in the boundary plane. This result, which has been termed the multiplicity of grain boundary structures, has also been found in the simulation of tilt boundaries. The multiplicity phenomenon is of special interest in twist boundaries since it is used as a structural model to explain the x-ray scattering from a Σ = 5 boundary in gold. These scattering patterns had previously remained unexplained using stable structures that had simple CSL periodicity. Also, the effect of having a multiple number of low energy structural units coexisting in the grain boundary is of more general interest since it implies that the boundary structures may be quasi-periodic and, in some circumstances, may even result in a roughening of the boundary plane. This paper extends this work by showing, using molecular dynamics, that a multiplicity of structural units can actually nucleate spontaneously in a high-angle grain boundary at finite temperatures

  5. Factors associated with nocturnal hypoglycemia in at-risk adolescents and young adults with type 1 diabetes.

    Science.gov (United States)

    Wilson, Darrell M; Calhoun, Peter M; Maahs, David M; Chase, H Peter; Messer, Laurel; Buckingham, Bruce A; Aye, Tandy; Clinton, Paula K; Hramiak, Irene; Kollman, Craig; Beck, Roy W

    2015-06-01

    Hypoglycemia remains an impediment to good glycemic control, with nocturnal hypoglycemia being particularly dangerous. Information on major contributors to nocturnal hypoglycemia remains critical for understanding and mitigating risk. Continuous glucose monitoring (CGM) data for 855 nights were studied, generated by 45 subjects 15-45 years of age with hemoglobin A1c (HbA1c) levels of ≤8.0% who participated in a larger randomized study. Factors assessed for potential association with nocturnal hypoglycemia (CGM measurement of <60 mg/dL for ≥30 min) included bedtime blood glucose (BG), exercise intensity, bedtime snack, insulin on board, day of the week, previous daytime hypoglycemia, age, gender, HbA1c level, diabetes duration, daily basal insulin, and daily insulin dose. Hypoglycemia occurred during 221 of 885 (25%) nights and was more frequent with younger age (P<0.001), lower HbA1c levels (P=0.006), medium/high-intensity exercise during the preceding day (P=0.003), and the occurrence of antecedent daytime hypoglycemia (P=0.001). There was a trend for lower bedtime BG levels to be associated with more frequent nocturnal hypoglycemia (P=0.10). Bedtime snack, before bedtime insulin bolus, weekend versus weekday, gender, and daily basal and bolus insulin were not associated with nocturnal hypoglycemia. Awareness that HbA1c level, exercise, bedtime BG level, and daytime hypoglycemia are all modifiable factors associated with nocturnal hypoglycemia may help patients and providers decrease the risk of hypoglycemia at night. Risk for nocturnal hypoglycemia increased in a linear fashion across the range of variables, with no clear-cut thresholds to guide clinicians or patients for any particular night.

  6. Primary nocturnal enuresis is associated with lower intelligence quotient scores in boys from poorer socioeconomic status families.

    Science.gov (United States)

    Basiri, Abbas; Bahrainian, Seyed Abdolmajid; Khoshdel, Alireza; Jalaly, Niloofar; Golshan, Shabnam; Pakmanesh, Hamid

    2017-03-01

    To explore intelligence quotient in boys with primary nocturnal enuresis compared with normal boys considering their socioeconomic status. A total of 152 school-aged boys (including 55 boys with primary nocturnal enuresis and 97 matched normal controls) were assessed. Boys with a history of any neurological or urological disease were excluded. Two different districts of Tehran: Khani-Abad (a poor district) and Pirouzi (a middle class district) districts were enrolled according to socioeconomic status data reported by the World Health Organization. Intelligence tests were carried out using a validated Iranian translation of the Wechsler Intelligence Scale for Children Revised. Total, as well as performance intelligence quotient and verbal intelligence quotient scores and verbal-performance discrepancy (the difference between verbal and performance intelligence quotient scores for each individual) were compared using a t-test between boys with primary nocturnal enuresis in each district and their matched controls. Considering each district separately, the total intelligence quotient score was lower in primary nocturnal enuresis cases than controls only in the lower income district (90.7 ± 23.3 vs 104.8 ± 14.7, P = 0.002). Similarly, boys with primary nocturnal enuresis ranked lower in verbal intelligence quotient (P = 0.002) and performance intelligence quotient (P = 0.004) compared with their matched normal controls only in lower income district, whereas in the higher income district, boys with primary nocturnal enuresis ranked similar in total intelligence quotient to their matched controls. Boys with primary nocturnal enuresis had a lower intelligence quotient compared with the control participants only in low-income district. It seems important to adjust the results of the intelligence quotient assessment in these children according to their socioeconomic status. © 2017 The Japanese Urological Association.

  7. The Bottom Boundary Layer.

    Science.gov (United States)

    Trowbridge, John H; Lentz, Steven J

    2018-01-03

    The oceanic bottom boundary layer extracts energy and momentum from the overlying flow, mediates the fate of near-bottom substances, and generates bedforms that retard the flow and affect benthic processes. The bottom boundary layer is forced by winds, waves, tides, and buoyancy and is influenced by surface waves, internal waves, and stratification by heat, salt, and suspended sediments. This review focuses on the coastal ocean. The main points are that (a) classical turbulence concepts and modern turbulence parameterizations provide accurate representations of the structure and turbulent fluxes under conditions in which the underlying assumptions hold, (b) modern sensors and analyses enable high-quality direct or near-direct measurements of the turbulent fluxes and dissipation rates, and (c) the remaining challenges include the interaction of waves and currents with the erodible seabed, the impact of layer-scale two- and three-dimensional instabilities, and the role of the bottom boundary layer in shelf-slope exchange.

  8. The Bottom Boundary Layer

    Science.gov (United States)

    Trowbridge, John H.; Lentz, Steven J.

    2018-01-01

    The oceanic bottom boundary layer extracts energy and momentum from the overlying flow, mediates the fate of near-bottom substances, and generates bedforms that retard the flow and affect benthic processes. The bottom boundary layer is forced by winds, waves, tides, and buoyancy and is influenced by surface waves, internal waves, and stratification by heat, salt, and suspended sediments. This review focuses on the coastal ocean. The main points are that (a) classical turbulence concepts and modern turbulence parameterizations provide accurate representations of the structure and turbulent fluxes under conditions in which the underlying assumptions hold, (b) modern sensors and analyses enable high-quality direct or near-direct measurements of the turbulent fluxes and dissipation rates, and (c) the remaining challenges include the interaction of waves and currents with the erodible seabed, the impact of layer-scale two- and three-dimensional instabilities, and the role of the bottom boundary layer in shelf-slope exchange.

  9. The magnetic nature of umbra-penumbra boundary in sunspots

    Science.gov (United States)

    Jurčák, J.; Rezaei, R.; González, N. Bello; Schlichenmaier, R.; Vomlel, J.

    2018-03-01

    Context. Sunspots are the longest-known manifestation of solar activity, and their magnetic nature has been known for more than a century. Despite this, the boundary between umbrae and penumbrae, the two fundamental sunspot regions, has hitherto been solely defined by an intensity threshold. Aim. Here, we aim at studying the magnetic nature of umbra-penumbra boundaries in sunspots of different sizes, morphologies, evolutionary stages, and phases of the solar cycle. Methods: We used a sample of 88 scans of the Hinode/SOT spectropolarimeter to infer the magnetic field properties in at the umbral boundaries. We defined these umbra-penumbra boundaries by an intensity threshold and performed a statistical analysis of the magnetic field properties on these boundaries. Results: We statistically prove that the umbra-penumbra boundary in stable sunspots is characterised by an invariant value of the vertical magnetic field component: the vertical component of the magnetic field strength does not depend on the umbra size, its morphology, and phase of the solar cycle. With the statistical Bayesian inference, we find that the strength of the vertical magnetic field component is, with a likelihood of 99%, in the range of 1849-1885 G with the most probable value of 1867 G. In contrast, the magnetic field strength and inclination averaged along individual boundaries are found to be dependent on the umbral size: the larger the umbra, the stronger and more horizontal the magnetic field at its boundary. Conclusions: The umbra and penumbra of sunspots are separated by a boundary that has hitherto been defined by an intensity threshold. We now unveil the empirical law of the magnetic nature of the umbra-penumbra boundary in stable sunspots: it is an invariant vertical component of the magnetic field.

  10. Theory of stable allocations

    Directory of Open Access Journals (Sweden)

    Pantelić Svetlana

    2014-01-01

    Full Text Available The Swedish Royal Academy awarded the 2012 Nobel Prize in Economics to Lloyd Shapley and Alvin Roth, for the theory of stable allocations and the practice of market design. These two American researchers worked independently from each other, combining basic theory and empirical investigations. Through their experiments and practical design they generated a flourishing field of research and improved the performance of many markets. Born in 1923 in Cambridge, Massachusetts, Shapley defended his doctoral thesis at Princeton University in 1953. For many years he worked at RAND, and for more than thirty years he was a professor at UCLA University. He published numerous scientific papers, either by himself or in cooperation with other economists.

  11. Bi-stable optical actuator

    Science.gov (United States)

    Holdener, Fred R.; Boyd, Robert D.

    2000-01-01

    The present invention is a bi-stable optical actuator device that is depowered in both stable positions. A bearing is used to transfer motion and smoothly transition from one state to another. The optical actuator device may be maintained in a stable position either by gravity or a restraining device.

  12. Research and Development of Information and Communication Technology-based Home Blood Pressure Monitoring from Morning to Nocturnal Hypertension.

    Science.gov (United States)

    Kario, Kazuomi; Tomitani, Naoko; Matsumoto, Yuri; Hamasaki, Haruna; Okawara, Yukie; Kondo, Maiko; Nozue, Ryoko; Yamagata, Hiromi; Okura, Ayako; Hoshide, Satoshi

    2016-01-01

    Asians have specific characteristics of hypertension (HTN) and its relationship with cardiovascular disease. The morning surge in blood pressure (BP) in Asians is more extended, and the association slope between higher BP and the risk for cardiovascular events is steeper in this population than in whites. Thus, 24-hour BP control including at night and in the morning is especially important for Asian patients with HTN. There are 3 components of "perfect 24-hour BP control": the 24-hour BP level, adequate dipping of nocturnal BP (dipper type), and adequate BP variability such as the morning BP surge. The morning BP-guided approach using home BP monitoring (HBPM) is the first step toward perfect 24-hour BP control. After controlling morning HTN, nocturnal HTN is the second target. We have been developing HBPM that can measure nocturnal BP. First, we developed a semiautomatic HBPM device with the function of automatic fixed-interval BP measurement during sleep. In the J-HOP (Japan Morning Surge Home Blood Pressure) study, the largest nationwide home BP cohort, we successfully measured nocturnal home BP using this device with data memory, 3 times during sleep (2, 3, and 4 am), and found that nocturnal home BP is significantly correlated with organ damage independently of office and morning BP values. The second advance was the development of trigger nocturnal BP (TNP) monitoring with an added trigger function that initiates BP measurements when oxygen desaturation falls below a variable threshold continuously monitored by pulse oximetry. TNP can detect the specific nocturnal BP surges triggered by hypoxic episodes in patients with sleep apnea syndrome. We also added the lowest heart rate-trigger function to TNP to detect the "basal nocturnal BP," which is determined by the circulating volume and structural cardiovascular system without any increase in sympathetic tonus. This double TNP is a novel concept for evaluating the pathogenic pressor mechanism of nocturnal BP

  13. Diamagnetic boundary layers: a kinetic theory

    International Nuclear Information System (INIS)

    Lemaire, J.; Burlaga, L.F.

    1976-01-01

    A kinetic theory for boundary layers associated with MHD tangential 'discontinuities' in a collisionless magnetized plasma such as those observed in the solar wind is presented. The theory consists of finding self-consistent solutions of Vlasov's equation and Maxwell's equation for stationary, one-dimensional boundary layers separating two Maxwellian plasma states. Layers in which the current is carried by electrons are found to have a thickness of the order of a few electron gyroradii, but the drift speed of the current-carrying electrons is found to exceed the Alfven speed, and accordingly such layers are not stable. Several types of layers, in which the current is carried by protons are discussed; in particular, cases in which the magnetic field intensity and/or direction changed across the layer were considered. In every case, the thickness was of the order of a few proton gyroradii and the field changed smoothly , although the characteristics depended somewhat on the boundary conditions. The drift speed was always less than the Alfven speed, consistent with stability of such structures. The results are consistent with the observations of boundary layers in the solar wind near 1 AU. (Auth.)

  14. The Effectiveness of Silodosin for Nocturnal Polyuria in Elderly Men With Benign Prostatic Hyperplasia: A Multicenter Study.

    Science.gov (United States)

    Kim, Young Won; Park, Jinsung; Chung, Hong; Kim, Hong-Wook; Kim, Hyung Joon; Jung, Jae Hung; Kim, Won Tae

    2015-09-01

    To investigate improvement in nocturia and nocturnal polyuria in nocturnal polyuria patients after silodosin administration by using a 3-day frequency volume chart. This was a prospective multicenter study. We enrolled nocturnal polyuria patients (nocturnal polyuria index [NPi]>0.33), aged ≥60 years, diagnosed with the 3-day frequency volume charts of patients with benign prostatic hyperplasia taking α-blockers. Of the 54 patients, 30 (55.6%) completed the study according to the study protocol (per-protocol group), and 24 dropped out (dropout group). Of the 24 patients in the dropout group, 5 withdrew consent due to side effects or lack of efficacy, 7 were lost to follow-up at 4 weeks, 8 were lost to follow-up at 12 weeks, and 4 dropped out due to failure to complete 3-day frequency volume charts at 12 weeks. In the per-protocol group, there was significant improvement in the International Prostate Symptom Score (IPSS), especially question numbers 1, 3, 4, 5, 6, 7, and the quality of life question (P=0.001, P=0.007, Psilodosin monotherapy exhibits good efficacy in improving nocturia and nocturnal polyuria; however, the mean NPi was still >0.33. Considering the high dropout rate of our study due to no implementation of 3-day frequency volume charts, prospective and large-scale studies are needed to confirm our results.

  15. Expression and Evolution of Short Wavelength Sensitive Opsins in Colugos: A Nocturnal Lineage That Informs Debate on Primate Origins.

    Science.gov (United States)

    Moritz, Gillian L; Lim, Norman T-L; Neitz, Maureen; Peichl, Leo; Dominy, Nathaniel J

    2013-01-01

    A nocturnal activity pattern is central to almost all hypotheses on the adaptive origins of primates. This enduring view has been challenged in recent years on the basis of variation in the opsin genes of nocturnal primates. A correspondence between the opsin genes and activity patterns of species in Euarchonta-the superordinal group that includes the orders Primates, Dermoptera (colugos), and Scandentia (treeshrews)-could prove instructive, yet the basic biology of the dermopteran visual system is practically unknown. Here we show that the eye of the Sunda colugo ( Galeopterus variegatus ) lacks a tapetum lucidum and has an avascular retina, and we report on the expression and spectral sensitivity of cone photopigments. We found that Sunda colugos have intact short wavelength sensitive (S-) and long wavelength sensitive (L-) opsin genes, and that both opsins are expressed in cone photoreceptors of the retina. The inferred peak spectral sensitivities are 451 and 562 nm, respectively. In line with adaptation to nocturnal vision, cone densities are low. Surprisingly, a majority of S-cones coexpress some L-opsin. We also show that the ratio of rates of nonsynonymous to synonymous substitutions of exon 1 of the S-opsin gene is indicative of purifying selection. Taken together, our results suggest that natural selection has favored a functional S-opsin in a nocturnal lineage for at least 45 million years. Accordingly, a nocturnal activity pattern remains the most likely ancestral character state of euprimates.

  16. The influence of periodic increases of human activity on crepuscular and nocturnal mammals: Testing the weekend effect.

    Science.gov (United States)

    Nix, Joshua H; Howell, Ryan G; Hall, Lucas K; McMillan, Brock R

    2018-01-01

    Human recreation can negatively affect wildlife, particularly on weekends when human activity is highest (i.e., the weekend effect). Much of what we understand about the weekend effect is based on research conducted on diurnal species, which have greater temporal overlap with humans. Because nocturnal species generally avoid times when humans are active, they are likely less affected by anthropogenic activity on weekends. Our objective was to test the weekend effect in relation to the degree of nocturnality of mammals in a recreational area. We predicted that as nocturnality increased, the effect of human activity would decrease. To address our objective, we placed 50 remote cameras along the Diamond Fork River in Utah from January to June 2015. We found that three out of the four focal species supported our predictions. Mule deer (crepuscular) reduced activity throughout our entire study area during weekends and avoided campgrounds. Beavers and mountain lions (both nocturnal) did not negatively respond to increased human activity. Raccoons (nocturnal) reduced activity during weekends, but only within campground areas. Our findings indicate that as the temporal overlap increases between wildlife and humans, so does the influence that humans have on wildlife. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Salmeterol versus slow-release theophylline combined with ketotifen in nocturnal asthma: a multicentre trial. French Multicentre Study Group.

    Science.gov (United States)

    Muir, J F; Bertin, L; Georges, D

    1992-11-01

    We wished to assess the efficacy of inhaled salmeterol (SML; 50 micrograms b.i.d.) compared to a combination of slow-release theophylline and ketotifen p.o. (TK; T 300 mg+K 1 mg b.i.d.) for the treatment of nocturnal asthma. Ninety six patients with nocturnal asthma, (forced expiratory volume in one second (FEV1) 60-90% of predicted value, reversibility > or = 15%, at least two nocturnal awakenings per week) were eligible for a multicentre, double-blind, double-dummy cross-over study (14-day run-in, two successive 28-day treatment periods). Efficacy was assessed as success/failure, success being defined as the complete disappearance of nocturnal symptoms/awakening during the last week of each treatment period. There was a statistically significant difference between SML and TK for this criterion: 46% and 39% success with SML during periods I (first 28-day period) and II (following the cross-over), compared to only 15% and 26% with TK, respectively (p < 0.01). SML was also significantly better for the other criteria (lung function, rescue salbutamol intake during day and night). Side-effects were five times less frequent in SML-treated patients (p < 0.004). Efficacy and tolerance of SML were obviously far better than those of TK in patients with nocturnal asthma.

  18. Free-boundary stability of straight stellarators

    International Nuclear Information System (INIS)

    Barnes, D.C.; Cary, J.R.

    1984-02-01

    The sharp-boundary model is used to investigate the stability of straight stellarators to free-boundary, long-wavelength modes. To correctly analyze the heliac configuration, previous theory is generalized to the case of arbitrary helical aspect ratio (ratio of plasma radius to periodicity lengths). A simple low-β criterion involving the vacuum field and the normalized axial current is derived and used to investigate a large variety of configurations. The predictions of this low-β theory are verified by numerical minimization of deltaW at arbitrary β. The heliac configuration is found to be remarkably stable, with a critical β of over 15% determined by the lack of equilibrium rather than the onset of instability. In addition, other previously studied systems are found to be stabilized by net axial plasma current

  19. Minnesota County Boundaries - lines

    Data.gov (United States)

    Minnesota Department of Natural Resources — Minnesota county boundaries derived from a combination of 1:24,000 scale PLS lines, 1:100,000 scale TIGER, 1:100,000 scale DLG, and 1:24,000 scale hydrography lines....

  20. Boundary-Object Trimming

    DEFF Research Database (Denmark)

    Bossen, Claus; Jensen, Lotte Groth; Udsen, Flemming Witt

    2014-01-01

    implementation, which also coupled the work of medical secretaries more tightly to that of other staff, and led to task drift among professions. Medical secretaries have been relatively invisible to health informatics and CSCW, and we propose the term ‘boundary-object trimming’ to foreground and conceptualize...

  1. Minnesota County Boundaries

    Data.gov (United States)

    Minnesota Department of Natural Resources — Minnesota county boundaries derived from a combination of 1:24,000 scale PLS lines, 1:100,000 scale TIGER, 1:100,000 scale DLG, and 1:24,000 scale hydrography lines....

  2. Boundaries of the universe

    CERN Document Server

    Glasby, John S

    2013-01-01

    The boundaries of space exploration are being pushed back constantly, but the realm of the partially understood and the totally unknown is as great as ever. Among other things this book deals with astronomical instruments and their application, recent discoveries in the solar system, stellar evolution, the exploding starts, the galaxies, quasars, pulsars, the possibilities of extraterrestrial life and relativity.

  3. Conformal boundary loop models

    International Nuclear Information System (INIS)

    Jacobsen, Jesper Lykke; Saleur, Hubert

    2008-01-01

    We study a model of densely packed self-avoiding loops on the annulus, related to the Temperley-Lieb algebra with an extra idempotent boundary generator. Four different weights are given to the loops, depending on their homotopy class and whether they touch the outer rim of the annulus. When the weight of a contractible bulk loop x≡q+q -1 element of (-2,2], this model is conformally invariant for any real weight of the remaining three parameters. We classify the conformal boundary conditions and give exact expressions for the corresponding boundary scaling dimensions. The amplitudes with which the sectors with any prescribed number and types of non-contractible loops appear in the full partition function Z are computed rigorously. Based on this, we write a number of identities involving Z which hold true for any finite size. When the weight of a contractible boundary loop y takes certain discrete values, y r ≡([r+1] q )/([r] q ) with r integer, other identities involving the standard characters K r,s of the Virasoro algebra are established. The connection with Dirichlet and Neumann boundary conditions in the O(n) model is discussed in detail, and new scaling dimensions are derived. When q is a root of unity and y=y r , exact connections with the A m type RSOS model are made. These involve precise relations between the spectra of the loop and RSOS model transfer matrices, valid in finite size. Finally, the results where y=y r are related to the theory of Temperley-Lieb cabling

  4. Remifentanil inhibits rapid eye movement sleep but not the nocturnal melatonin surge in humans.

    Science.gov (United States)

    Bonafide, Christopher P; Aucutt-Walter, Natalie; Divittore, Nicole; King, Tonya; Bixler, Edward O; Cronin, Arthur J

    2008-04-01

    Postoperative patients are sleep deprived. Opioids, commonly administered for postoperative pain control, are often mistakenly considered inducers of naturally occurring sleep. This study describes the effect of the opioid remifentanil on nocturnal sleep in healthy volunteers. In addition, this study tests the hypothesis that opioid-induced sleep disturbance is caused by a circadian pacemaker disturbance, reflected by suppressed nocturnal plasma concentration of melatonin. Polysomnography was performed in 10 volunteers from 11:00 pm to 7:00 am for four nights at 6-day intervals. On two nights, remifentanil (0.01-0.04 microg x kg x min) was infused from 10:30 pm to 7:00 am, and either a placebo capsule or 3.0 mg melatonin was administered at 10:30 pm. On two additional nights, saline was infused, and the placebo or melatonin capsules were administered at 10:30 pm. Blood was drawn at 12:00 am, 3:00 am, and 6:00 am to measure the plasma concentration of melatonin and cortisol. A repeated-measures analysis of variance model was used to determine the effect of remifentanil on sleep stages, the effect of remifentanil on the plasma concentration of melatonin, and the effect of exogenous melatonin on remifentanil-induced sleep disturbance. Remifentanil inhibited rapid eye movement sleep (14.1 +/- 7.2% to 3.9 +/- 6.9%). The amount of slow wave sleep decreased from 6.8 +/- 7.6% to 3.2 +/- 6.1%, but this decrease was not statistically significant. Remifentanil did not decrease melatonin concentration. Melatonin administration did not prevent remifentanil-induced sleep disturbance. An overnight constant infusion of remifentanil inhibits rapid eye movement sleep without suppressing the nocturnal melatonin surge.

  5. Rates of nocturnal transpiration in two evergreen temperate woodland species with differing water-use strategies.

    Science.gov (United States)

    Zeppel, Melanie; Tissue, David; Taylor, Daniel; Macinnis-Ng, Catriona; Eamus, Derek

    2010-08-01

    Nocturnal fluxes may be a significant factor in the annual water budget of forested ecosystems. Here, we assessed sap flow in two co-occurring evergreen species (Eucalyptus parramattensis and Angophora bakeri) in a temperate woodland for 2 years in order to quantify the magnitude of seasonal nocturnal sap flow (E(n)) under different environmental conditions. The two species showed different diurnal water relations, demonstrated by different diurnal curves of stomatal conductance, sap flow and leaf water potential. The relative influence of several microclimatic variables, including wind speed (U), vapour pressure deficit (D), the product of U and D (UD) and soil moisture content, were quantified. D exerted the strongest influence on E(n) (r² = 0.59-0.86), soil moisture content influenced E(n) when D was constant, but U and UD did not generally influence E(n). In both species, cuticular conductance (G(c)) was a small proportion of total leaf conductance (G(s)) and was not a major pathway for E(n). We found that E(n) was primarily a function of transpiration from the canopy rather than refilling of stem storage, with canopy transpiration accounting for 50-70% of nocturnal flows. Mean E(n) was 6-8% of the 24-h flux across seasons (spring, summer and winter), but was up to 19% of the 24-h flux on some days in both species. Despite different daytime strategies in water use of the two species, both species demonstrated low night-time water loss, suggesting similar controls on water loss at night. In order to account for the impact of E(n) on pre-dawn leaf water potential arising from the influence of disequilibria between root zone and leaf water potential, we also developed a simple model to more accurately predict soil water potential (ψ(s)).

  6. Evaluation of depression and self-esteem in children with monosymptomatic nocturnal enuresis: A controlled trial

    Directory of Open Access Journals (Sweden)

    Orhan Koca

    2014-09-01

    Full Text Available Objectives: Nocturnal enuresis (NE is very common and is one of the most common causes for patients to be admitted to urology, pediatrics, child psychiatry and child surgery departments. We aimed to investigate the effect on depression and self-esteem of this disorder that can cause problems on person's social development and human relations. Material and methods: 90 patients who were admitted to our clinic with complaints of nocturnal enuresis were enrolled. Investigations to rule out organic causes were performed in this group of patients. Out of them 38 children and adolescents (age range 8-18 years with primary monosymptomatic nocturnal enuresis (PMNE agreed to participate in the study In the same period 46 healthy children and adolescents with a similar age range without bed wetting complaint were included in the study as a control group. The age of the family, educational and socioeconomic level were questioned and Piers-Harris Children's Self-Concept Scale (PHCSCS and Children's Depression Inventory (CDI forms were filled out. Results: Mean age of the cases (18 females or 47.4% and 20 males or 52.6% was 10.76 ± 3.82 years whereas mean age of controls (26 females or 56.5% and 20 males or 43.5% was 10.89 ± 3.11 years. Depression scale was significantly higher (p = 0.001 in the case group than in the control group (10.42 ± 4.31 vs 7.09 ± 4.35. In both groups there was no statistically significant difference by age and sex in terms of depression scale (p > 0.05. Conclusion: NE is widely seen as in the community and is a source of stresses either for children and for their families. When patients were admitted to physicians for treatment, a multidisciplinary approach should be offered and the necessary psychological support should be provided jointly by child psychiatrists and psychologists.

  7. Patterns of nocturnal rehydration in root tissues of Vaccinium corymbosum L. under severe drought conditions.

    Science.gov (United States)

    Valenzuela-Estrada, Luis R; Richards, James H; Diaz, Andres; Eissensat, David M

    2009-01-01

    Although roots in dry soil layers are commonly rehydrated by internal hydraulic redistribution during the nocturnal period, patterns of tissue rehydration are poorly understood. Rates of nocturnal rehydration were examined in roots of different orders in Vaccinium corymbosum L. 'Bluecrop' (Northern highbush blueberry) grown in a split-pot system with one set of roots in relatively moist soil and the other set of roots in dry soil. Vaccinium is noted for a highly branched and extremely fine root system. It is hypothesized that nocturnal root tissue rehydration would be slow, especially in the distal root orders because of their greater hydraulic constraints (smaller vessel diameters and fewer number of vessels). Vaccinium root hydraulic properties delayed internal water movement. Even when water was readily available to roots in the wet soil and transpiration was minimal, it took a whole night-time period of 12 h for the distal finest roots (1st to 4th order) under dry soil conditions to reach the same water potentials as fine roots in moist soil (1st to 4th order). Even though roots under dry soil equilibrated with roots in moist soil, the equilibrium point reached before sunrise was about -1.2 MPa, indicating that tissues were not fully rehydrated. Using a single-branch root model, it was estimated that individual roots exhibiting the lowest water potentials in dry soil were 1st order roots (distal finest roots of the root system). However, considered at the branch level, root orders with the highest hydraulic resistances corresponded to the lowest orders of the permanent root system (3rd-, 4th-, and 5th-order roots), thus indicating possible locations of hydraulic safety control in the root system of this species.

  8. Examining nocturnal railway noise and aircraft noise in the field: sleep, psychomotor performance, and annoyance.

    Science.gov (United States)

    Elmenhorst, Eva-Maria; Pennig, Sibylle; Rolny, Vinzent; Quehl, Julia; Mueller, Uwe; Maaß, Hartmut; Basner, Mathias

    2012-05-01

    Traffic noise is interfering during day- and nighttime causing distress and adverse physiological reactions in large parts of the population. Railway noise proved less annoying than aircraft noise in surveys which were the bases for a so called 5 dB railway bonus regarding noise protection in many European countries. The present field study investigated railway noise-induced awakenings during sleep, nighttime annoyance and the impact on performance the following day. Comparing these results with those from a field study on aircraft noise allowed for a ranking of traffic modes concerning physiological and psychological reactions. 33 participants (mean age 36.2 years ± 10.3 (SD); 22 females) living alongside railway tracks around Cologne/Bonn (Germany) were polysomnographically investigated. These data were pooled with data from a field study on aircraft noise (61 subjects) directly comparing the effects of railway and aircraft noise in one random subject effects logistic regression model. Annoyance was rated in the morning evaluating the previous night. Probability of sleep stage changes to wake/S1 from railway noise increased significantly from 6.5% at 35 dB(A) to 20.5% at 80 dB(A) LAFmax. Rise time of noise events had a significant impact on awakening probability. Nocturnal railway noise led to significantly higher awakening probabilities than aircraft noise, partly explained by the different rise times, whereas the order was inversed for annoyance. Freight train noise compared to passenger train noise proved to have the most impact on awakening probability. Nocturnal railway noise had no effect on psychomotor vigilance. Nocturnal freight train noise exposure in Germany was associated with increased awakening probabilities exceeding those for aircraft noise and contrasting the findings of many annoyance surveys and annoyance ratings of our study. During nighttime a bonus for railway noise seems not appropriate. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Wind-related orientation patterns in diurnal, crepuscular and nocturnal high-altitude insect migrants

    Directory of Open Access Journals (Sweden)

    Gao eHu

    2016-02-01

    Full Text Available Most insect migrants fly at considerable altitudes (hundreds of meters above the ground where they utilize fast-flowing winds to achieve rapid and comparatively long-distance transport. The nocturnal aerial migrant fauna has been well studied with entomological radars, and many studies have demonstrated that flight orientations are frequently grouped around a common direction in a range of nocturnal insect migrants. Common orientation typically occurs close to the downwind direction (thus ensuring that a large component of the insects’ self-powered speed is directed downstream, and in nocturnal insects at least, the downwind headings are seemingly maintained by direct detection of wind-related turbulent cues. Despite being far more abundant and speciose, the day-flying windborne migrant fauna has been much less studied by radar; thus the frequency of wind-related common orientation patterns and the sensory mechanisms involved in their formation remain to be established. Here we analyze a large dataset of >600,000 radar-detected ‘medium-sized’ windborne insect migrants (body mass from 10 to 70 mg, flying hundreds of meters above southern UK, during the afternoon, in the period around sunset, and in the middle of the night. We found that wind-related common orientation was almost ubiquitous during the day (present in 97% of all ‘migration events’ analyzed, and was also frequent at sunset (85% and at night (81%. Headings were systematically offset to the right of the flow at night-time (as predicted from the use of turbulence cues for flow assessment, but there was no directional bias in the offsets during the day or at sunset. Orientation ‘performance’ significantly increased with increasing flight altitude throughout the day and night. We conclude by discussing sensory mechanisms which most likely play a role in the selection and maintenance of wind-related flight headings.

  10. Vertical Distribution of Daily Migrating Mesopelagic Fish in Respect to Nocturnal Lights

    KAUST Repository

    Prihartato, Perdana

    2014-12-01

    The nighttime distribution of vertically migrating mesopelagic fish in relation to nocturnal light was studied during a circumglobal survey, in the Red Sea, and in a fjord at high latitude. The study was based on data derived from ship borne echo sounders (circumglobal and the Red Sea) as well as using upward looking echo sounders mounted on the bottom (Masfjorden, Norway). We also applied a numerical model for analyzing diel vertical migration patterns. The effect of the lunar cycle was the focus in studies at low latitudes, while seasonal changes in nocturnal light climate was in focus at high latitude. Lunar phase significantly affected the distribution of mesopelagic fish at the global scale and in the Red Sea. During nights near full moon, scattering layers of mesopelagic fish distributed deeper than during darker phases of the moon. At high latitude, mesopelagic fish switched its behavior along with seasonal changes in nocturnal lights. In autumn, the population of the studied fish (Maurolicus mueleri) formed separated layers. Juveniles performed normal diel vertical migration followed by midnight sinking, with midnight sinking mainly related to temperature minima and also for avoiding predators. Meanwhile the adults did not migrate vertically, reducing foraging but increasing the adult survival. From late winter to mid-Spring, interrupted ascents behavior was noted in the afternoon. Predator avoidance, satiation, and finding temperature optimum might be the reason behind interrupted ascents. At lighter nights in mid-summer, M. muelleri took on schooling behavior, likely as an anti-predator behavior permitting access to the upper waters in the absence of darkness.

  11. Is nocturnal eating in restless legs syndrome linked to a specific psychopathological profile? A pilot study.

    Science.gov (United States)

    Marconi, Sara; Scarlatti, Fabiano; Rizzo, Giovanni; Antelmi, Elena; Innamorati, Marco; Pompili, Maurizio; Brugnoli, Roberto; Belvederi Murri, Martino; Amore, Mario; Provini, Federica

    2015-11-01

    The purpose of the study was to evaluate psychological comorbidity in drug-naive or drug-free primary restless legs syndrome (p-RLS) patients with nocturnal eating disorder (NED), and to analyze the association of comorbid p-RLS and NED with obsessive-compulsive, mood and anxiety symptoms, and personality. Participants comprised 20 consecutive female outpatients with p-RLS, 10 without NED and 10 with NED, and 10 female controls matched for age. Both patients and controls were evaluated by the Hamilton Depression and the Anxiety Rating Scales, the State-Trait Anxiety Inventory, the Maudsley Obsessive Compulsive Inventory and the temperament and character inventory-revised. Compared to controls, p-RLS patients without and with NED had higher trait anxiety and current anxiety and obsessive-compulsive symptoms. p-RLS patients with NED also had significantly higher doubting compared to p-RLS patients without NED. Furthermore, groups differed for harm avoidance (HA), with p-RLS patients with and without NED having higher scores than controls. Untreated p-RLS patients, particularly those with nocturnal eating, report anxiety and obsessive-compulsive symptoms, perceive stressful situations as dangerous and threatening and tend to respond with anxiety to such situations. They have higher tendency to respond intensely to aversive stimuli, inhibiting behavior to avoid punishment, novelty, and frustrative omission of expected rewards. We hypothesize that higher levels of HA, a biologically determined personality trait, might constitute a diathesis predisposing individuals to display obsessive-compulsive symptoms, namely increasingly severe compulsive nocturnal eating.

  12. Nocturnal Hot Flashes: Relationship to Objective Awakenings and Sleep Stage Transitions

    Science.gov (United States)

    Bianchi, Matt T.; Kim, Semmie; Galvan, Thania; White, David P.; Joffe, Hadine

    2016-01-01

    Study Objectives: While women report sleep interruption secondary to nighttime hot flashes, the sleep disrupting impact of nocturnal hot flashes (HF) is not well characterized. We utilized a model of induced HF to investigate the relationship of nighttime HF to sleep architecture and sleep-stage transitions. Methods: Twenty-eight healthy, premenopausal volunteers received the depot gonadotropin-releasing hormone agonist (GnRHa) leuprolide to rapidly induce menopause, manifesting with HF. Sleep disruption was measured on 2 polysomnograms conducted before and after 4–5 weeks on leuprolide, when HF had developed. Results: 165 HF episodes were recorded objectively during 48 sleep studies (mean 3.4 HF/night). After standardizing to sleep-stage time distribution, the majority of HF were recorded during wake (51.0%) and stage N1 (18.8%). Sixty-six percent of HF occurred within 5 minutes of an awakening, with 80% occurring just before or during the awakening. Objective HF were not associated with sleep disruption as measured by increased transitions to wake or N1, but self-reported nocturnal HF correlated with an increase from pre- to post-leuprolide in the rate of transitions to wake (p = 0.01), and to N1 (p = 0.008). Conclusions: By isolating the effect of HF on sleep in women without the confound of age-related sleep changes associated with natural menopause, this experimental model shows that HF arise most commonly during N1 and wake, typically preceding or occurring simultaneously with wake episodes. Perception of HF, but not objective HF, is linked to increased sleep-stage transitions, suggesting that sleep disruption increases awareness of and memory for nighttime HF events. Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT01116401. Citation: Bianchi MT, Kim S, Galvan T, White DP, Joffe H. Nocturnal hot flashes: relationship to objective awakenings and sleep stage transitions. J Clin Sleep Med 2016;12(7):1003–1009. PMID:26951410

  13. Individual-based ant-plant networks: diurnal-nocturnal structure and species-area relationship.

    Directory of Open Access Journals (Sweden)

    Wesley Dáttilo

    Full Text Available Despite the importance and increasing knowledge of ecological networks, sampling effort and intrapopulation variation has been widely overlooked. Using continuous daily sampling of ants visiting three plant species in the Brazilian Neotropical savanna, we evaluated for the first time the topological structure over 24 h and species-area relationships (based on the number of extrafloral nectaries available in individual-based ant-plant networks. We observed that diurnal and nocturnal ant-plant networks exhibited the same pattern of interactions: a nested and non-modular pattern and an average level of network specialization. Despite the high similarity in the ants' composition between the two collection periods, ant species found in the central core of highly interacting species totally changed between diurnal and nocturnal sampling for all plant species. In other words, this "night-turnover" suggests that the ecological dynamics of these ant-plant interactions can be temporally partitioned (day and night at a small spatial scale. Thus, it is possible that in some cases processes shaping mutualistic networks formed by protective ants and plants may be underestimated by diurnal sampling alone. Moreover, we did not observe any effect of the number of extrafloral nectaries on ant richness and their foraging on such plants in any of the studied ant-plant networks. We hypothesize that competitively superior ants could monopolize individual plants and allow the coexistence of only a few other ant species, however, other alternative hypotheses are also discussed. Thus, sampling period and species-area relationship produces basic information that increases our confidence in how individual-based ant-plant networks are structured, and the need to consider nocturnal records in ant-plant network sampling design so as to decrease inappropriate inferences.

  14. Seasonal patterns in the nocturnal distributionand behavior of the mesopelagic fish Maurolicus muelleri at high latitudes

    KAUST Repository

    Prihartato, Perdana

    2015-02-17

    Acoustic scattering layers (SL) ascribed to pearlside Maurolicus muelleri were studied in Masfjorden, Norway, using upward-looking echo sounders cabled to shore for continuous long-term measurements. The acoustic studies were accompanied by continuous measurements of surface light and supplemented with intermittent field campaigns. From autumn to spring, young M. muelleri formed an SL in the upper ∼75 to 150 m in the daytime, characterized by migration to near-surface water near dusk, subsequent \\'midnight sinking\\', followed by a dawn ascent before a return to the daytime habitat. Light levels were ∼1 order of magnitude lower during the dawn ascent than for ascent in the afternoon, with the latter terminating before fish reached upper layers on ∼1/3 of the nights from late November to mid-April. Adults showed less tendency of migration during autumn and winter, until the SLs of young and adults merged in late spring, and thereafter displayed coherent migration behavior. The midnight sinking became progressively deeper from autumn to winter but was strongly reduced from mid-May when the darkest nocturnal light intensity (PAR) at the surface was above 10-3 μmol m-2 s-1. The pearlside took on schooling in upper waters during the even lighter nights in early June, with minimum light of ∼5 × 10-3 to 10-1 μmol m-2 s-1 at the surface. Nocturnal schooling ceased in early July, and midnight sinking reappeared in mid-August. We suggest that the strong variation in nocturnal light intensity at high latitudes provides changing trade-offs between visual foraging and avoiding predators and hence varying time budgets for feeding in the upper, productive layers.

  15. Effect of CPAP Therapy on Symptoms of Nocturnal Gastroesophageal Reflux among Patients with Obstructive Sleep Apnea.

    Science.gov (United States)

    Tamanna, Sadeka; Campbell, Douglas; Warren, Richard; Ullah, Mohammad I

    2016-09-15

    Nocturnal gastroesophageal reflux (nGER) is common among patients with obstructive sleep apnea (OSA). Previous studies demonstrated that continuous positive airway pressure (CPAP) reduces symptoms of nGER. However, improvement in nGER symptoms based on objective CPAP compliance has not been documented. We have examined the polysomnographic characteristics of patients with nGER and OSA and looked for association of OSA severity and CPAP compliance with improvement in nGER symptoms. We interviewed 85 veterans with OSA to assess their daytime sleepiness (Epworth Sleepiness scale [ESS]) and nGER symptom frequency after their polysomnography and polysomnographic data were reviewed. At 6 months' follow-up, ESS score, nGER score, and CPAP machine compliance data were reassessed. Data from 6 subjects were dropped from final analysis due to their initiation of new medication for nGER symptom since the initial evaluation. Sixty-two of 79 (78%) patients complained of nGER symptoms during initial visit. At baseline, nGER score was correlated with sleep efficiency (r = 0.43), and BMI correlated with the severity of OSA (r = 0.41). ESS and nGER improved (p CPAP compliant patients. A minimum CPAP compliance of 25% was needed to achieve any benefit in nGER improvement. Nocturnal gastroesophageal reflux is common among patients with OSA which increases sleep disruption and worsens the symptoms of daytime sleepiness. CPAP therapy may help improve the symptoms of both nocturnal acid reflux and daytime sleepiness, but adherence to CPAP is crucial to achieve this benefit. © 2016 American Academy of Sleep Medicine.

  16. Adaptive strategies in nocturnally migrating insects and songbirds: contrasting responses to wind.

    Science.gov (United States)

    Chapman, Jason W; Nilsson, Cecilia; Lim, Ka S; Bäckman, Johan; Reynolds, Don R; Alerstam, Thomas

    2016-01-01

    Animals that use flight as their mode of transportation must cope with the fact that their migration and orientation performance is strongly affected by the flow of the medium they are moving in, that is by the winds. Different strategies can be used to mitigate the negative effects and benefit from the positive effects of a moving flow. The strategies an animal can use will be constrained by the relationship between the speed of the flow and the speed of the animal's own propulsion in relation to the surrounding air. Here we analyse entomological and ornithological radar data from north-western Europe to investigate how two different nocturnal migrant taxa, the noctuid moth Autographa gamma and songbirds, deal with wind by analysing variation in resulting flight directions in relation to the wind-dependent angle between the animal's heading and track direction. Our results, from fixed locations along the migratory journey, reveal different global strategies used by moths and songbirds during their migratory journeys. As expected, nocturnally migrating moths experienced a greater degree of wind drift than nocturnally migrating songbirds, but both groups were more affected by wind in autumn than in spring. The songbirds' strategies involve elements of both drift and compensation, providing some benefits from wind in combination with destination and time control. In contrast, moths expose themselves to a significantly higher degree of drift in order to obtain strong wind assistance, surpassing the songbirds in mean ground speed, at the cost of a comparatively lower spatiotemporal migratory precision. Moths and songbirds show contrasting but adaptive responses to migrating through a moving flow, which are fine-tuned to the respective flight capabilities of each group in relation to the wind currents they travel within. © 2015 The Authors. Journal of Animal Ecology © 2015 British Ecological Society.

  17. Creating designs as effective boundary objects in innovation journeys?

    NARCIS (Netherlands)

    Bos, A.P.; Bommel, van S.; Klerkx, L.W.A.

    2012-01-01

    In innovation processes, prospects are often seen as a strategic tool to connect multiple actors. They are perceived to be flexible enough to have meaning in all social worlds, and stable enough to travel back and forth between them. In other words, effective prospects are seen as boundary objects

  18. Sleep positions and nocturnal body movements based on free-living accelerometer recordings

    DEFF Research Database (Denmark)

    Skarpsno, Eivind Schjelderup; Mork, Paul Jarle; Nilsen, Tom Ivar Lund

    2017-01-01

    Background: In order to establish normative values for body positions and movements during sleep, the objective of this study was to explore the distribution of sleep positions and extent of nocturnal body moments and the association with sex, age, body-mass index (BMI), smoking, alcohol......), but more arm, thigh, and upper-back movements compared to normal-weight participants. Smokers had fewer shifts in body position than nonsmokers (-0.27, 95% CI -0.4 to -0.13). Conclusion: The predominant sleep position in adults is on the side. This preference increases with age and BMI. The extent...

  19. A nocturnal decline of salivary pH associated with airway hyperresponsiveness in asthma

    OpenAIRE

    Watanabe, Masanari; Sano, Hiroyuki; Tomita, Katsuyuki; Yamasaki, Akira; Kurai, Jun; Hasegawa, Yasuyuki; Igishi, Tadashi; Okazaki, Ryota; Tohda, Yuji; Burioka, Naoto; Shimizu, Eiji

    2010-01-01

    Salivary pH is associated with esophageal acid reflux and neutralization ofesophageal acid. In this study, we assessed the association between nocturnal decline ofsalivary pH and airway hyperresponsiveness. Salivary pH was serially assessed in 9 patientswith mild asthma (7 men and 2 women ;mean age 33.3 years ;mean %predictedFEV1.0 89.4%) and 10 healthy volunteers (6 men and 4 women ; mean age 31.2 years) usinga pH indicator tape. The buffering capacity of saliva was defined as the median eff...

  20. In-car nocturnal blue light exposure improves motorway driving: a randomized controlled trial.

    Directory of Open Access Journals (Sweden)

    Jacques Taillard

    Full Text Available Prolonged wakefulness greatly decreases nocturnal driving performance. The development of in-car countermeasures is a future challenge to prevent sleep-related accidents. The aim of this study is to determine whether continuous exposure to monochromatic light in the short wavelengths (blue light, placed on the dashboard, improves night-time driving performance. In this randomized, double-blind, placebo-controlled, cross-over study, 48 healthy male participants (aged 20-50 years drove 400 km (250 miles on motorway during night-time. They randomly and consecutively received either continuous blue light exposure (GOLite, Philips, 468 nm during driving or 2*200 mg of caffeine or placebo of caffeine before and during the break. Treatments were separated by at least 1 week. The outcomes were number of inappropriate line crossings (ILC and mean standard deviation of the lateral position (SDLP. Eight participants (17% complained about dazzle during blue light exposure and were removed from the analysis. Results from the 40 remaining participants (mean age ± SD: 32.9±11.1 showed that countermeasures reduced the number of inappropriate line crossings (ILC (F(2,91.11 = 6.64; p<0.05. Indeed, ILC were lower with coffee (12.51 [95% CI, 5.86 to 19.66], p = 0.001 and blue light (14.58 [CI, 8.75 to 22.58], p = 0.003 than with placebo (26.42 [CI, 19.90 to 33.71]. Similar results were found for SDLP. Treatments did not modify the quality, quantity and timing of 3 subsequent nocturnal sleep episodes. Despite a lesser tolerance, a non-inferior efficacy of continuous nocturnal blue light exposure compared with caffeine suggests that this in-car countermeasure, used occasionally, could be used to fight nocturnal sleepiness at the wheel in blue light-tolerant drivers, whatever their age. More studies are needed to determine the reproducibility of data and to verify if it can be generalized to women.ClinicalTrials.gov NCT01070004.