Hawaiian Starlight: Sharing the Beauty of the Hawaiian Skies

NASA Astrophysics Data System (ADS)

Cuillandre, J. C.

Canada-France-Hawaii Telescope Corp. The summit of Mauna Kea (14,000 feet) offers the best viewing of the Cosmos in the northern hemisphere, and the film "Hawaiian Starlight" delivers a pure esthetic experience from the mountain into the Universe. Seven years in the making, this cinematic symphony reveals the spectacular beauty of the mountain and its connection to the Cosmos through the magical influence of time-lapse cinematography scored exclusively (no narration) with the awe-inspiring, critically acclaimed, Halo music by Martin O'Donnell and Michael Salvatori. Daytime and nighttime landscapes and skyscapes alternate with stunning true color images of the Universe captured by an observatory on Mauna Kea, all free of any computer generated imagery. An extended segment of the film will be presented at the Advanced Maui Optical and Space Surveillance Technologies Conference to celebrate the international year of Astronomy 2009, a global effort initiated by the IAU (International Astronomical Union) and UNESCO (United Nations Educational, Scientific and Cultural Organization) to help the citizens of the world rediscover their place in the Universe through the day- and night-time sky, and thereby engage a personal sense of wonder and discovery. Hawaiian Starlight is true to this commitment. The inspiration and technology of the film will be shortly presented by the film's director.

Night-time activity forecast by season and weather in a longitudinal design - natural light effects on three years' rest-activity cycles in nursing home residents with dementia.

PubMed

Wahnschaffe, Amely; Nowozin, Claudia; Rath, Andreas; Floessner, Theresa; Appelhoff, Stefan; Münch, Mirjam; Kunz, Dieter

2017-12-01

Backround: Night-time agitation is a frequent symptom of dementia. It often causes nursing home admission and has been linked to circadian rhythm disturbances. A positive influence of light interventions on night-time agitation was shown in several studies. The aim of our study was to investigate whether there is a long-term association between regional weather data (as indicator for daylight availability) and 24-hour variations of motor activity. Motor activity of 20 elderly nursing home residents living with dementia was analyzed using recordings of continuously worn wrist activity monitors over a three-year period. The average recording duration was 479 ± 206 days per participant (mean ± SD). Regional cloud amount and day length data from the local weather station (latitude: 52°56'N) were included in the analysis to investigate their effects on several activity variables. Nocturnal rest, here defined as the five consecutive hours with the least motor activity during 24 hours (L5), was the most predictable activity variable per participant. There was a significant interaction of night-time activity with day length and cloud amount (F 1,1174 = 4.39; p = 0.036). Night-time activity was higher on cloudy short days than on clear short days (p = 0.007), and it was also higher on cloudy short days than on cloudy long days (p = 0.032). The need for sufficient zeitgeber (time cue) strength during winter time, especially when days are short and skies are cloudy, is crucial for elderly people living with dementia. Activity forecast by season and weather might be a valuable approach to anticipate adequately complementary use of electrical light and thereby foster lower night-time activity.

TWAN: The World at Night

NASA Astrophysics Data System (ADS)

Tafreshi, Babak A.

2011-06-01

The World at Night (TWAN) is a global program to produce, collect, and present stunning photographs and time-lapse videos of the world's most beautiful and historic sites against the night-time backdrop of stars, planets, and celestial events. TWAN is a bridge between art, science and humanity to bring the message of peace, concealed in the sky. Organised by ``Astronomers Without Borders'', the project consist of world's best night sky photographers in over countries and coordinators, regional event organisers, and consultants. TWAN was also designated as a Special Project of the International Year of Astronomy 2009. While the project's global exhibitions and educational events peaked during IYA2009, TWAN is planned for long term in several phases and will continue to create and exhibit images in the next years.

Worldwide variations in artificial skyglow

PubMed Central

Kyba, Christopher C. M.; Tong, Kai Pong; Bennie, Jonathan; Birriel, Ignacio; Birriel, Jennifer J.; Cool, Andrew; Danielsen, Arne; Davies, Thomas W.; Outer, Peter N. den; Edwards, William; Ehlert, Rainer; Falchi, Fabio; Fischer, Jürgen; Giacomelli, Andrea; Giubbilini, Francesco; Haaima, Marty; Hesse, Claudia; Heygster, Georg; Hölker, Franz; Inger, Richard; Jensen, Linsey J.; Kuechly, Helga U.; Kuehn, John; Langill, Phil; Lolkema, Dorien E.; Nagy, Matthew; Nievas, Miguel; Ochi, Nobuaki; Popow, Emil; Posch, Thomas; Puschnig, Johannes; Ruhtz, Thomas; Schmidt, Wim; Schwarz, Robert; Schwope, Axel; Spoelstra, Henk; Tekatch, Anthony; Trueblood, Mark; Walker, Constance E.; Weber, Michael; Welch, Douglas L.; Zamorano, Jaime; Gaston, Kevin J.

2015-01-01

Despite constituting a widespread and significant environmental change, understanding of artificial nighttime skyglow is extremely limited. Until now, published monitoring studies have been local or regional in scope, and typically of short duration. In this first major international compilation of monitoring data we answer several key questions about skyglow properties. Skyglow is observed to vary over four orders of magnitude, a range hundreds of times larger than was the case before artificial light. Nearly all of the study sites were polluted by artificial light. A non-linear relationship is observed between the sky brightness on clear and overcast nights, with a change in behavior near the rural to urban landuse transition. Overcast skies ranged from a third darker to almost 18 times brighter than clear. Clear sky radiances estimated by the World Atlas of Artificial Night Sky Brightness were found to be overestimated by ~25%; our dataset will play an important role in the calibration and ground truthing of future skyglow models. Most of the brightly lit sites darkened as the night progressed, typically by ~5% per hour. The great variation in skyglow radiance observed from site-to-site and with changing meteorological conditions underlines the need for a long-term international monitoring program. PMID:25673335

Assessment of capabilities of lidar systems in day-and night-time under different atmospheric and internal-noise conditions

NASA Astrophysics Data System (ADS)

Agishev, Ravil; Comerón, Adolfo

2018-04-01

As an application of the dimensionless parameterization concept proposed earlier for the characterization of lidar systems, the universal assessment of lidar capabilities in day and night conditions is considered. The dimensionless parameters encapsulate the atmospheric conditions, the lidar optical and optoelectronic characteristics, including the photodetector internal noise, and the sky background radiation. Approaches to ensure immunity of the lidar system to external background radiation are discussed.

A gap-filling model for eddy covariance CO2 flux: Estimating carbon assimilated by a subtropical evergreen broad-leaved forest at the Lien-Hua-Chih flux observation site

NASA Astrophysics Data System (ADS)

Lan, C. Y.; Li, M. H.; Chen, Y. Y.

2016-12-01

Appropriate estimations of gaps appeared in eddy covariance (EC) flux observations are critical to the reliability of long-term EC applications. In this study we present a semi-parametric multivariate gap-filling model for tower-based measurement of CO2 flux. The raw EC data passing QC/QA was separated into two groups, clear sky, having net radiation greater than 50 W/m2, and nighttime/cloudy. For the clear sky conditions, the principle component analysis (PCA) was used to resolve the multicollinearity relationships among various environmental variables, including net radiation, wind speed, vapor pressure deficit, soil moisture deficit, leaf area index, and soil temperature, in association with CO2 assimilated by forest. After the principal domains were determined by the PCA, the relationships between CO2 fluxes and selected PCs (key factors) were built up by nonlinear interpolations to estimate the gap-filled CO2 flux. In view of limited photosynthesis at nighttime/cloudy conditions, respiration rate of the forest ecosystem was estimated by the Lloyd-Tylor equation. Artificial gaps were randomly selected to exam the applicability of our PCA approach. Based on tower-based measurement of CO2 flux at the Lien-Hua-Chih site, a total of 5.8 ton-C/ha/yr was assimilated in 2012.

On the impact of cloudiness on the characteristics of nocturnal downslope flows

NASA Astrophysics Data System (ADS)

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

1989-10-01

The effects of cloud cover amount and the height of cloud base on nighttime thermally induced downslope flow were investigated using analytical and numerical model approaches. The conclusions obtained with the analytical and the numerical model evaluations agreed. It was concluded that, (i) as cloud cover increases and/or the height of cloud base decreases, the depth and the intensity of nighttime thermally-induced downslope flows may decrease by a factor reaching one sixth and one tenth, respectively, in the case of overcast low cloud; (ii) when skies suddenly cloud over around midnight, the development of the downslope flow is altered in different ways: a reduction in intensity; or a cessation of further development, depending on the fraction of cloud coverage, and (iii) with a sudden clearing of overcast low cloud around midnight, the depth and the intensity of the downslope flow increases significantly.

Contrasting trends in light pollution across Europe based on satellite observed night time lights.

PubMed

Bennie, Jonathan; Davies, Thomas W; Duffy, James P; Inger, Richard; Gaston, Kevin J

2014-01-21

Since the 1970s nighttime satellite images of the Earth from space have provided a striking illustration of the extent of artificial light. Meanwhile, growing awareness of adverse impacts of artificial light at night on scientific astronomy, human health, ecological processes and aesthetic enjoyment of the night sky has led to recognition of light pollution as a significant global environmental issue. Links between economic activity, population growth and artificial light are well documented in rapidly developing regions. Applying a novel method to analysis of satellite images of European nighttime lights over 15 years, we show that while the continental trend is towards increasing brightness, some economically developed regions show more complex patterns with large areas decreasing in observed brightness over this period. This highlights that opportunities exist to constrain and even reduce the environmental impact of artificial light pollution while delivering cost and energy-saving benefits.

Elixir - how to handle 2 trillion pixels

NASA Astrophysics Data System (ADS)

Magnier, Eugene A.; Cuillandre, Jean-Charles

2002-12-01

The Elixir system at CFHT provides automatic data quality assurance and calibration for the wide-field mosaic imager camera CFH12K. Elixir consists of a variety of tools, including: a real-time analysis suite which runs at the telescope to provide quick feedback to the observers; a detailed analysis of the calibration data; and an automated pipeline for processing data to be distributed to observers. To date, 2.4 × 1012 night-time sky pixels from CFH12K have been processed by the Elixir system.

Measuring and Characterizing Sky Brightness over the Nighttime in Tucson and Surrounding Observatory Mountaintops

NASA Astrophysics Data System (ADS)

Walker, C. E.; Jensen, L.; Pompea, S. M.

2012-12-01

Research interns are using 6 Sky Quality Meters (SQM) around Tucson and 4 more on nearby observatory mountaintops to measure the night sky brightness and characterize its behavior over the entire night over the summer and during the academic school year. The "SQM" devices are inexpensive, yet reliable, computer-free devices, automatically log data, and have housing to protect them from weather. The students download the data onto a computer every few weeks. Two devices are at a central location on the roof of the National Optical Astronomy Observatory (NOAO) and the others are 9 miles N, E, S and W. Four more devices are on observatory mountaintops, namely Mount Lemmon, Mount Hopkins and 2 on Kitt Peak. For the pair of devices at NOAO and on Kitt Peak, one is in the housing unit and the other is exposed to the night sky to track the lossiness of the glass in the housing unit. The SQM is next to the sophisticated and more expensive "Night Sky Brightness Monitor" (NSBM) on Mount Lemmon, Mount Hopkins and, in the future, Kitt Peak. The student interns compare the SQM to the NSBM data on the mountaintops, weather data (temperature and humidity), internal temperature of the SQM, the all-sky camera that is up on Kitt Peak and the SQM results from Tucson. Weather stations already exist very close to all of the locations (usually within a mile or a few feet). We discuss the students' analysis of the data and conclusions as well as the challenges and successes of the program and its plans for expansion.

Light Pollution and Wildlife

NASA Astrophysics Data System (ADS)

Duffek, J.

2008-12-01

for Educational Program IYA Dark Skies Education Session Fall American Geophysical Union San Francisco, December 15-19, 2008 Light Pollution and Wildlife This is a very exciting time to be a part of the mission to keep the nighttime skies natural. The International Year of Astronomy (IYA) 2009 is developing programs for all areas of Dark Skies Awareness. For many years the issue of light pollution focused on the impact to the astronomy industry. While this is an important area, research has shown that light pollution negatively impacts wildlife, their habitat, human health, and is a significant waste of energy. Since the message and impact of the effects of light pollution are much broader now, the message conveyed to the public must also be broader. Education programs directed at youth are a new frontier to reach out to a new audience about the adverse effects of too much artificial light at night. The International Dark-Sky Association (IDA) has developed educational presentations using the National Science Teachers Association Education Standards. These programs focus on youth between the ages of 5 to 17exploring new territory in the education of light pollution. The IDA education programs are broken down into three age groups; ages 5-9, 8-13, 12 and older. The presentations come complete with PowerPoint slides, discussion notes for each slide, and workbooks including age appropriate games to keep young audiences involved. A new presentation reflects the growing area of interest regarding the effects of too much artificial light at night on wildlife. This presentation outlines the known problems for ecosystems caused by artificial light at night. Insects are attracted to artificial lights and may stay near that light all night. This attraction interferes with their ability to migrate, mate, and look for food. Such behavior leads to smaller insect populations. Fewer insects in turn affect birds and bats, because they rely on insects as a food source. The IDA education programs show children how all of these issues are interrelated. Insects are not the only organisms adversely affected by light at night. Reptiles, mammals, birds and amphibians are also negatively impacted. All creatures have a biological clock which determines when they rest, hunt, migrate, and mate. Bright lights create confusion in many species by disrupting this internal biological clock. IDA presents the solutions to these problems as quality outdoor lighting, and the presentations show examples of dark sky friendly lighting. The youth audience is an excellent venue for wildlife education outreach. The IDA youth education programs are completed and ready for use. They can be used by professional teachers, parents, community organizers, or anyone advocating to keep the skies natural. This is a great time to promote the win-win benefits of good nighttime lighting.

Predicting Ground Illuminance

NASA Astrophysics Data System (ADS)

Lesniak, Michael V.; Tregoning, Brett D.; Hitchens, Alexandra E.

2015-01-01

Our Sun outputs 3.85 x 1026 W of radiation, of which roughly 37% is in the visible band. It is directly responsible for nearly all natural illuminance experienced on Earth's surface, either in the form of direct/refracted sunlight or in reflected light bouncing off the surfaces and/or atmospheres of our Moon and the visible planets. Ground illuminance, defined as the amount of visible light intercepting a unit area of surface (from all incident angles), varies over 7 orders of magnitude from day to night. It is highly dependent on well-modeled factors such as the relative positions of the Sun, Earth, and Moon. It is also dependent on less predictable factors such as local atmospheric conditions and weather.Several models have been proposed to predict ground illuminance, including Brown (1952) and Shapiro (1982, 1987). The Brown model is a set of empirical data collected from observation points around the world that has been reduced to a smooth fit of illuminance against a single variable, solar altitude. It provides limited applicability to the Moon and for cloudy conditions via multiplicative reduction factors. The Shapiro model is a theoretical model that treats the atmosphere as a three layer system of light reflectance and transmittance. It has different sets of reflectance and transmittance coefficients for various cloud types.In this paper we compare the models' predictions to ground illuminance data from an observing run at the White Sands missile range (data was obtained from the United Kingdom's Meteorology Office). Continuous illuminance readings were recorded under various cloud conditions, during both daytime and nighttime hours. We find that under clear skies, the Shapiro model tends to better fit the observations during daytime hours with typical discrepancies under 10%. Under cloudy skies, both models tend to poorly predict ground illuminance. However, the Shapiro model, with typical average daytime discrepancies of 25% or less in many cases, performed somewhat better than the Brown model during daytime hours. During nighttime hours under cloudy skies, both models produced erratic results.

Method for Ground-to-Satellite Laser Calibration System

NASA Technical Reports Server (NTRS)

Lukashin, Constantine (Inventor); Wielicki, Bruce A. (Inventor)

2015-01-01

The present invention comprises an approach for calibrating the sensitivity to polarization, optics degradation, spectral and stray light response functions of instruments on orbit. The concept is based on using an accurate ground-based laser system, Ground-to-Space Laser Calibration (GSLC), transmitting laser light to instrument on orbit during nighttime substantially clear-sky conditions. To minimize atmospheric contribution to the calibration uncertainty the calibration cycles should be performed in short time intervals, and all required measurements are designed to be relative. The calibration cycles involve ground operations with laser beam polarization and wavelength changes.

Method for Ground-to-Space Laser Calibration System

NASA Technical Reports Server (NTRS)

Lukashin, Constantine (Inventor); Wielicki, Bruce A. (Inventor)

2014-01-01

The present invention comprises an approach for calibrating the sensitivity to polarization, optics degradation, spectral and stray light response functions of instruments on orbit. The concept is based on using an accurate ground-based laser system, Ground-to-Space Laser Calibration (GSLC), transmitting laser light to instrument on orbit during nighttime substantially clear-sky conditions. To minimize atmospheric contribution to the calibration uncertainty the calibration cycles should be performed in short time intervals, and all required measurements are designed to be relative. The calibration cycles involve ground operations with laser beam polarization and wavelength changes.

Encroachment of Human Activity on Sea Turtle Nesting Sites

NASA Astrophysics Data System (ADS)

Ziskin, D.; Aubrecht, C.; Elvidge, C.; Tuttle, B.; Baugh, K.; Ghosh, T.

2008-12-01

The encroachment of anthropogenic lighting on sea turtle nesting sites poses a serious threat to the survival of these animals [Nicholas, 2001]. This danger is quantified by combining two established data sets. The first is the Nighttime Lights data produced by the NOAA National Geophysical Data Center [Elvidge et al., 1997]. The second is the Marine Turtle Database produced by the World Conservation Monitoring Centre (WCMC). The technique used to quantify the threat of encroachment is an adaptation of the method described in Aubrecht et al. [2008], which analyzes the stress on coral reef systems by proximity to nighttime lights near the shore. Nighttime lights near beaches have both a direct impact on turtle reproductive success since they disorient hatchlings when they mistake land-based lights for the sky-lit surf [Lorne and Salmon, 2007] and the lights are also a proxy for other anthropogenic threats. The identification of turtle nesting sites with high rates of encroachment will hopefully steer conservation efforts to mitigate their effects [Witherington, 1999]. Aubrecht, C, CD Elvidge, T Longcore, C Rich, J Safran, A Strong, M Eakin, KE Baugh, BT Tuttle, AT Howard, EH Erwin, 2008, A global inventory of coral reef stressors based on satellite observed nighttime lights, Geocarto International, London, England: Taylor and Francis. In press. Elvidge, CD, KE Baugh, EA Kihn, HW Kroehl, ER Davis, 1997, Mapping City Lights with Nighttime Data from the DMSP Operational Linescan System, Photogrammatic Engineering and Remote Sensing, 63:6, pp. 727-734. Lorne, JK, M Salmon, 2007, Effects of exposure to artificial lighting on orientation of hatchling sea turtles on the beach and in the ocean, Endangered Species Research, Vol. 3: 23-30. Nicholas, M, 2001, Light Pollution and Marine Turtle Hatchlings: The Straw that Breaks the Camel's Back?, George Wright Forum, 18:4, p77-82. Witherington, BE, 1999, Reducing Threats To Nesting Habitat, Research and Management Techniques for the Conservation of Sea Turtles, KL Eckert, KA Bjorndal, FAA Grobois, M Donnelly, eds., IUCN/SSC Marine Turtle Specialist Group.

Role of City Texture in Urban Heat Islands at Nighttime

NASA Astrophysics Data System (ADS)

Sobstyl, J. M.; Emig, T.; Qomi, M. J. Abdolhosseini; Ulm, F.-J.; Pellenq, R. J.-M.

2018-03-01

An urban heat island (UHI) is a climate phenomenon that results in an increased air temperature in cities when compared to their rural surroundings. In this Letter, the dependence of an UHI on urban geometry is studied. Multiyear urban-rural temperature differences and building footprints data combined with a heat radiation scaling model are used to demonstrate for more than 50 cities worldwide that city texture—measured by a building distribution function and the sky view factor—explains city-to-city variations in nocturnal UHIs. Our results show a strong correlation between nocturnal UHIs and the city texture.

Outreach and Astronomy-Education Activities of the University of Arizona Astronomy Club

NASA Astrophysics Data System (ADS)

McGraw, Allison M.; Hardegree-Ullman, K.; Walker-LaFollette, A.; Towner, A. P.

2014-01-01

The University of Arizona Astronomy Club provides unique outreach experiences for all ages. Our undergraduates work together to volunteer their time for various types of outreach events. This club uses several techniques to execute astronomy education such as hands-on 3D models, exciting demonstrations of scientific phenomena, and multiple small telescopes for both solar and night-time viewing. The students bring the models and telescopes to locations both on and off campus; from dark sky locations in the desert southwest to elementary schools, our undergraduates are willing to teach astronomy just about anywhere.

Role of City Texture in Urban Heat Islands at Nighttime.

PubMed

Sobstyl, J M; Emig, T; Qomi, M J Abdolhosseini; Ulm, F-J; Pellenq, R J-M

2018-03-09

An urban heat island (UHI) is a climate phenomenon that results in an increased air temperature in cities when compared to their rural surroundings. In this Letter, the dependence of an UHI on urban geometry is studied. Multiyear urban-rural temperature differences and building footprints data combined with a heat radiation scaling model are used to demonstrate for more than 50 cities worldwide that city texture-measured by a building distribution function and the sky view factor-explains city-to-city variations in nocturnal UHIs. Our results show a strong correlation between nocturnal UHIs and the city texture.

Improved Correction of IR Loss in Diffuse Shortwave Measurements: An ARM Value-Added Product

DOE Office of Scientific and Technical Information (OSTI.GOV)

Younkin, K; Long, CN

Simple single black detector pyranometers, such as the Eppley Precision Spectral Pyranometer (PSP) used by the Atmospheric Radiation Measurement (ARM) Program, are known to lose energy via infrared (IR) emission to the sky. This is especially a problem when making clear-sky diffuse shortwave (SW) measurements, which are inherently of low magnitude and suffer the greatest IR loss. Dutton et al. (2001) proposed a technique using information from collocated pyrgeometers to help compensate for this IR loss. The technique uses an empirically derived relationship between the pyrgeometer detector data (and alternatively the detector data plus the difference between the pyrgeometer casemore » and dome temperatures) and the nighttime pyranometer IR loss data. This relationship is then used to apply a correction to the diffuse SW data during daylight hours. We developed an ARM value-added product (VAP) called the SW DIFF CORR 1DUTT VAP to apply the Dutton et al. correction technique to ARM PSP diffuse SW measurements.« less

Ultraviolet to optical diffuse sky emission as seen by the Hubble Space Telescope Faint Object Spectrograph

NASA Astrophysics Data System (ADS)

Kawara, Kimiaki; Matsuoka, Yoshiki; Sano, Kei; Brandt, Timothy D.; Sameshima, Hiroaki; Tsumura, Kohji; Oyabu, Shinki; Ienaka, Nobuyuki

2017-04-01

We present an analysis of the blank-sky spectra observed with the Faint Object Spectrograph on board the Hubble Space Telescope. We study the diffuse sky emission from ultraviolet to optical wavelengths, which is composed of zodiacal light (ZL), diffuse Galactic light (DGL), and residual emission. The observations were performed towards 54 fields distributed widely over the sky, with spectral coverage from 0.2 to 0.7 μm. In order to avoid contaminating light from earthshine, we use the data collected only in orbital nighttime. The observed intensity is decomposed into the ZL, DGL, and residual emission, in eight photometric bands spanning our spectral coverage. We found that the derived ZL reflectance spectrum is flat in the optical, which indicates major contribution of C-type asteroids to the interplanetary dust (IPD). In addition, the ZL reflectance spectrum has an absorption feature at ∼0.3 μm. The shape of the DGL spectrum is consistent with those found in earlier measurements and model predictions. While the residual emission contains a contribution from the extragalactic background light, we found that the spectral shape of the residual looks similar to the ZL spectrum. Moreover, its optical intensity is much higher than that measured from beyond the IPD cloud by Pioneer 10/11, and also than that of the integrated galaxy light. These findings may indicate the presence of an isotropic ZL component, which is missed in the conventional ZL models.

"Dark Skies, Bright Kids" -- Astronomy Education and Outreach in Rural Virginia

NASA Astrophysics Data System (ADS)

Zasowski, Gail; Johnson, K.; Beaton, R.; Carlberg, J.; Czekala, I.; de Messieres, G.; Drosback, M.; Filipetti, C.; Gugliucci, N.; Hoeft, A.; Jackson, L.; Lynch, R.; Romero, C.; Sivakoff, G.; Whelan, D.; Wong, A.

2010-01-01

In the hills of central Virginia, the extraordinarily dark nighttime skies of southern Albemarle County provide a natural outdoor classroom for local science education. Until recently, this rural area lacked the financial and educational support to take full advantage of this rare and valuable natural resource. With funds provided by the NSF, a team of volunteers from the University of Virginia introduced a new program this fall called "Dark Skies - Bright Kids," which promotes science education at the elementary school level through a wide range of activities. The program volunteers (comprising undergraduate and graduate students, postdocs, and faculty) have sought to develop a coherent schedule of fun and educational activities throughout the semester, with emphases on hands-on learning and critical thinking. For example, students learn about the constellations by making star-wheels, about rocketry by building and launching rockets, and about comets by assembling miniature analogs. Additional activities include stories about the scientific and cultural history of astronomy, visits by professional astronomers and popular book authors, and astronomy-themed exercises in art, music, and physical education. These projects are designed to make astronomy, and by extension all science, accessible and appealing to each student. Family involvement is important in any educational environment, particularly at the elementary school level. To include the students' families and the larger community in "Dark Skies," we hold weekly telescope observing sessions at the school. Here, all interested parties can come together to hear what the students are learning and view astronomical objects through a small telescope. We hope that this well-received program will soon expand to other disadvantaged schools in the area. The "Dark Skies" team is proud and excited to have an impact on the scientific literacy of the students in these starry-skied communities!

Climatology of Diffusion Potential Classes for Minneapolis-St. Paul.

NASA Astrophysics Data System (ADS)

Johnson, Allen B.; Baker, Donald G.

1997-12-01

This climatological study reports on the potential for atmospheric diffusion at Minneapolis-St. Paul, Minnesota, cities located in the heart of the North American continent. As such, the results can be considered typical of an urban setting within a continental climate.Data were obtained from a nearly continuous 8-yr record of vertical temperature and wind measurements made on a 152.4-m tower. Temperature lapse rates between 21.3 and 152.4 m were grouped into three stability categories: 1) isothermal-inversion, 2) subadiabatic, and 3) superadiabatic. A subdivision of each was based upon wind speeds of less than 4 m s1 and greater than or equal to 4 m s1, resulting in six classes that were examined according to wind direction, time of day, time of year and, most importantly, the associated synoptic conditions.The isothermal-inversion condition was limited to nighttime periods, especially when high pressure centers were dominant and winds were less than 4 m s1. The highest frequency of occurrence was during midsummer, while the lowest was during late fall and early winter. The subadiabatic condition was primarily a nighttime phenomenon, except for the winter season when it was also common during the day. An interesting feature of the diurnal frequencies was that a morning and evening subadiabatic peak occurred due to the transition between nighttime stable and the daytime unstable conditions. The superadiabatic condition was mainly a daytime phenomenon and dominated the early afternoon period throughout the year.The lowest diffusion potential, a result of very stable air and light winds, occurred during the nighttime period, particularly when under the influence of a high pressure center. Weak to moderate diffusion potential, found to occur with weakly stable air and light to moderate winds, was associated with the perimeter of the high pressure center and also with overcast skies near a low pressure center. This condition normally occurred during the night as well as during windy days. Moderate to high diffusion potential, resulting from superadiabatic conditions and light to moderate winds, dominated the early afternoon period. Strong nighttime ventilation was restricted to the winter season when northwesterly winds dominated the region immediately behind a cold front.

Nighttime Clouds in Martian Arctic (Accelerated Movie)

NASA Technical Reports Server (NTRS)

2008-01-01

An angry looking sky is captured in a movie clip consisting of 10 frames taken by the Surface Stereo Imager on NASA's Phoenix Mars Lander.

The clip accelerates the motion. The images were take around 3 a.m. local solar time at the Phoenix site during Sol 95 (Aug. 30), the 95th Martian day since landing.

The swirling clouds may be moving generally in a westward direction over the lander.

The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

Continuous All-Sky Cloud Measurements: Cloud Fraction Analysis Based on a Newly Developed Instrument

NASA Astrophysics Data System (ADS)

Aebi, C.; Groebner, J.; Kaempfer, N.; Vuilleumier, L.

2017-12-01

Clouds play an important role in the climate system and are also a crucial parameter for the Earth's surface energy budget. Ground-based measurements of clouds provide data in a high temporal resolution in order to quantify its influence on radiation. The newly developed all-sky cloud camera at PMOD/WRC in Davos (Switzerland), the infrared cloud camera (IRCCAM), is a microbolometer sensitive in the 8 - 14 μm wavelength range. To get all-sky information the camera is located on top of a frame looking downward on a spherical gold-plated mirror. The IRCCAM has been measuring continuously (day and nighttime) with a time resolution of one minute in Davos since September 2015. To assess the performance of the IRCCAM, two different visible all-sky cameras (Mobotix Q24M and Schreder VIS-J1006), which can only operate during daytime, are installed in Davos. All three camera systems have different software for calculating fractional cloud coverage from images. Our study analyzes mainly the fractional cloud coverage of the IRCCAM and compares it with the fractional cloud coverage calculated from the two visible cameras. Preliminary results of the measurement accuracy of the IRCCAM compared to the visible camera indicate that 78 % of the data are within ± 1 octa and even 93 % within ± 2 octas. An uncertainty of 1-2 octas corresponds to the measurement uncertainty of human observers. Therefore, the IRCCAM shows similar performance in detection of cloud coverage as the visible cameras and the human observers, with the advantage that continuous measurements with high temporal resolution are possible.

Urban Soil: Assessing Ground Cover Impact on Surface Temperature and Thermal Comfort.

PubMed

Brandani, Giada; Napoli, Marco; Massetti, Luciano; Petralli, Martina; Orlandini, Simone

2016-01-01

The urban population growth, together with the contemporary deindustrialization of metropolitan areas, has resulted in a large amount of available land with new possible uses. It is well known that urban green areas provide several benefits in the surrounding environment, such as the improvement of thermal comfort conditions for the population during summer heat waves. The purpose of this study is to provide useful information on thermal regimes of urban soils to urban planners to be used during an urban transformation to mitigate surface temperatures and improve human thermal comfort. Field measurements of solar radiation, surface temperature (), air temperature (), relative humidity, and wind speed were collected on four types of urban soils and pavements in the city of Florence during summer 2014. Analysis of days under calm, clear-sky condition is reported. During daytime, sun-to-shadow differences for , apparent temperature index (ATI), and were significantly positive for all surfaces. Conversely, during nighttime, differences among all surfaces were significantly negative, whereas ATI showed significantly positive differences. Moreover, was significantly negative for grass and gravel. Relative to the shaded surfaces, was higher on white gravel and grass than gray sandstone and asphalt during nighttime, whereas gray sandstone was always the warmest surface during daytime. Conversely, no differences were found during nighttime for ATI and measured over surfaces that were exposed to sun during the day, whereas showed higher values on gravel than grass and asphalt during nighttime. An exposed surface warms less if its albedo is high, leading to a significant reduction of during daytime. These results underline the importance of considering the effects of surface characteristics on surface temperature and thermal comfort. This would be fundamental for addressing urban environment issues toward the heat island mitigation considering also the impact of urban renovation on microclimate. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

The Night Sky on Mars

NASA Technical Reports Server (NTRS)

2005-01-01

Taking advantage of extra solar energy collected during the day, NASA's Mars Exploration Rover Spirit settled in for an evening of stargazing, photographing the two moons of Mars as they crossed the night sky. This time-lapse composite, acquired the evening of Spirit's martian sol 590 (Aug. 30, 2005) from a perch atop 'Husband Hill' in Gusev Crater, shows Phobos, the brighter moon, on the left, and Deimos, the dimmer moon, on the right. In this sequence of images obtained every 170 seconds, both moons move from top to bottom. The bright star Aldebaran forms a trail on the right, along with some other stars in the constellation Taurus. Most of the other streaks in the image mark the collision of cosmic rays with pixels in the camera.

Scientists will use images of the two moons to better map their orbital positions, learn more about their composition, and monitor the presence of nighttime clouds or haze. Spirit took the six images that make up this composite using Spirit's panoramic camera with the camera's broadband filter, which was designed specifically for acquiring images under low-light conditions.

Effects of the Large June 1975 Meteoroid Storm on Earth's Ionosphere.

PubMed

Kaufmann, P; Kuntz, V L; Leme, N M; Piazza, L R; Boas, J W; Brecher, K; Crouchley, J

1989-11-10

The June 1975 meteoroid storm detected on the moon by the Apollo seismometers was the largest ever observed. Reexamination of radio data taken at that time showed that the storm also produced pronounced disturbances on Earth, which were recorded as unique phase anomalies on very low frequency (VLF) radio propagation paths in the low terrestrial ionosphere. Persistent effects were observed for the major storm period (20 to 30 June 1975), including reductions in the diurnal phase variation, advances in the nighttime and daytime phase levels, and reductions in the sunset phase delay rate. Large nighttime phase advances, lasting a few hours, were detected on some days at all VLF transmissions, and for the shorter propagation path they were comparable to solar Lyman alpha daytime ionization. Ion production rates attributable to the meteor storm were estimated to be about 0.6 to 3.0 ions per centimeter cubed per second at the E and D regions, respectively. The storm was a sporadic one with a radiant (that is, the point of apparent origin in the sky) located in the Southern Hemisphere, with a right ascension 1 to 2 hours larger than the sun's right ascension.

Diurnal variation of atmospheric water vapor at Gale crater: Analysis from ground-based measurements

NASA Astrophysics Data System (ADS)

Martinez, German; McConnochie, Timothy; Renno, Nilton; Meslin, Pierre-Yves; Fischer, Erik; Vicente-Retortillo, Alvaro; Borlina, Caue; Kemppinen, Osku; Genzer, Maria; Harri, Ari-Matti; de la Torre-Juárez, Manuel; Zorzano, Mari-Paz; Martin-Torres, Javier; Bridges, Nathan; Maurice, Sylvestre; Gasnault, Olivier; Gomez-Elvira, Javier; Wiens, Roger

2016-04-01

We analyze measurements obtained by Curiosity's Rover Environmental Monitoring Station (REMS) and ChemCam (CCAM) instruments to shed light on the hydrological cycle at Gale crater. In particular, we use nighttime REMS measurements taken when the atmospheric volume mixing ratio (VMR) and its uncertainty are the lowest (between 05:00 and 06:00 LTST) [1], and daytime CCAM passive sky measurements taken when the VMR is expected to be the highest (between 10:00 and 14:00 LTST) [2]. VMR is calculated from simultaneous REMS measurements of pressure (P), temperature (T) and relative humidity (RH) at 1.6 m (VMR is defined as RH×es(T)/P , where es is the saturation water vapor pressure over ice). The REMS relative humidity sensor has recently been recalibrated (June 2015), providing RH values slightly lower than those in the previous calibration (Dec 2014). The full diurnal cycle of VMR cannot be analyzed using only REMS data because the uncertainty in daytime VMR derived from REMS measurements is extremely high. Daytime VMR is inferred by fitting the output of a multiple-scattering discrete-ordinates radiative transfer model to CCAM passive sky observations [3]. CCAM makes these observations predominately in the vicinity of 11:00 - 12:00 LTST, but occasionally in the early morning near 08:00 LTST. We find that throughout the Martian year, the daytime VMR is higher than at night, with a maximum day-to-night ratio of about 6 during winter. Various processes might explain the differences between nighttime REMS and daytime CCAM VMR values. Potential explanations include: (i) surface nighttime frost formation followed by daytime sublimation [1], (ii) surface nighttime adsorption of water vapor by the regolith followed by daytime desorption and (iii) large scale circulations changing vertical H2O profiles at different times of the year. Potential formation of surface frost can only occur in late fall and winter [1], coinciding with the time when the diurnal amplitude of the near-surface VMR at Gale is maximum, while adsorption/desorption by the regolith can occur throughout the year [2]. Adsorption by the regolith is expected to be more efficient at lower temperatures (i.e. winter), although it remains unclear whether kinetics would allow for the exchange of adsorbed water on hourly time scales necessary to track insolation [4-5]. Local surface-atmosphere interactions, either via frost formation and/or exchange of adsorbed water with the atmosphere, might play a significant role in the diurnal hydrological cycle at Gale. REFERENCES: [1] Martínez G. M. et al. (2016) Icarus, doi: http://dx.doi.org/10.1016/j.icarus.2015.12.004 [2] Savijärvi H. (2016) Icarus, 265, 63-69. [3] McConnochie T. et al. (2015) AGU Fall Meeting. [4] Beck P. et al. (2010) JGR, 115, E10011. [5] Zent A. P. et al. (2001) JGR, 106, 14667-14674.

Survey Strategy Optimization for the Atacama Cosmology Telescope

NASA Technical Reports Server (NTRS)

De Bernardis, F.; Stevens, J. R.; Hasselfield, M.; Alonso, D.; Bond, J. R.; Calabrese, E.; Choi, S. K.; Crowley, K. T.; Devlin, M.; Wollack, E. J.

2016-01-01

In recent years there have been significant improvements in the sensitivity and the angular resolution of the instruments dedicated to the observation of the Cosmic Microwave Background (CMB). ACTPol is the first polarization receiver for the Atacama Cosmology Telescope (ACT) and is observing the CMB sky with arcmin resolution over approximately 2000 square degrees. Its upgrade, Advanced ACTPol (AdvACT), will observe the CMB in five frequency bands and over a larger area of the sky. We describe the optimization and implementation of the ACTPol and AdvACT surveys. The selection of the observed fields is driven mainly by the science goals, that is, small angular scale CMB measurements, B-mode measurements and cross-correlation studies. For the ACTPol survey we have observed patches of the southern galactic sky with low galactic foreground emissions which were also chosen to maximize the overlap with several galaxy surveys to allow unique cross-correlation studies. A wider field in the northern galactic cap ensured significant additional overlap with the BOSS spectroscopic survey. The exact shapes and footprints of the fields were optimized to achieve uniform coverage and to obtain cross-linked maps by observing the fields with different scan directions. We have maximized the efficiency of the survey by implementing a close to 24-hour observing strategy, switching between daytime and nighttime observing plans and minimizing the telescope idle time. We describe the challenges represented by the survey optimization for the significantly wider area observed by AdvACT, which will observe roughly half of the low-foreground sky. The survey strategies described here may prove useful for planning future ground-based CMB surveys, such as the Simons Observatory and CMB Stage IV surveys.

Astronomy Meets the Environmental Sciences: Using GLOBE at Night Data

NASA Astrophysics Data System (ADS)

Barringer, D.; Walker, C. E.; Pompea, S. M.; Sparks, R. T.

2011-09-01

The GLOBE at Night database now contains over 52,000 observations from the five annual two-week campaigns. It can be used as a resource to explore various issues related to light pollution and our environment. Students can compare data over time to look for changes and trends. For example, they can compare the data to population density or with nighttime photography and spectroscopy of lights. The data can be used in a lighting survey, to search for dark sky oases or to monitor ordinance compliance. Students can study effects of light pollution on animals, plants, human health, safety, security, energy consumption, and cost. As an example, we used data from the GLOBE at Night project and telemetry tracking data of lesser long-nosed bats obtained by the Arizona Game and Fish Department to study the effects of light pollution on the flight paths of the bats between their day roosts and night foraging areas around the city of Tucson, AZ. With the visual limiting magnitude data from GLOBE at Night, we ran a compositional analysis with respect to the bats' flight paths to determine whether the bats were selecting for or against flight through regions of particular night sky brightness levels. We found that the bats selected for the regions in which the limiting sky magnitudes fell between the ranges of 2.8-3.0 to 3.6-3.8 and 4.4-4.6 to 5.0-5.2, suggesting that the lesser long-nosed bat can tolerate a fair degree of urbanization. We also compared this result to contour maps created with digital Sky Quality Meter (http://www.unihedron.com) data.

First Study on the Occurrence Frequency of Equatorial Plasma Bubbles over West Africa Using an All-Sky Airglow Imager and GNSS Receivers

NASA Astrophysics Data System (ADS)

Okoh, Daniel; Rabiu, Babatunde; Shiokawa, Kazuo; Otsuka, Yuichi; Segun, Bolaji; Falayi, Elijah; Onwuneme, Sylvester; Kaka, Rafiat

2017-12-01

This is the first paper that reports the occurrence frequency of equatorial plasma bubbles and their dependences of local time, season, and geomagnetic activity based on airglow imaging observations at West Africa. The all-sky imager, situated in Abuja (Geographic: 8.99°N, 7.38°E; Geomagnetic: 1.60°S), has a 180° fisheye view covering almost the entire airspace of Nigeria. Plasma bubbles are observed for 70 nights of the 147 clear-sky nights from 9 June 2015 to 31 January 2017. Differences between nighttime and daytime ROTIs were also computed as a proxy of plasma bubbles using Global Navigation Satellite Systems (GNSS) receivers within the coverage of the all-sky imager. Most plasma bubble occurrences are found during equinoxes and least occurrences during solstices. The occurrence rate of plasma bubbles was highest around local midnight and lower for hours farther away. Most of the postmidnight plasma bubbles were observed around the months of December to March, a period that coincides with the harmattan period in Nigeria. The on/off status of plasma bubble in airglow and GNSS observations were in agreement for 67.2% of the total 768 h, while we suggest several reasons responsible for the remaining 32.8% when the airglow and GNSS bubble status are inconsistent. A majority of the plasma bubbles were observed under relatively quiet geomagnetic conditions (Dst ≥ -40 and Kp ≤ 3), but there was no significant pattern observed in the occurrence rate of plasma bubbles as a function of geomagnetic activity. We suggest that geomagnetic activities could have either suppressed or promoted the occurrence of plasma bubbles.

Uncertainties of parameterized surface downward clear-sky shortwave and all-sky longwave radiation.

NASA Astrophysics Data System (ADS)

Gubler, S.; Gruber, S.; Purves, R. S.

2012-06-01

As many environmental models rely on simulating the energy balance at the Earth's surface based on parameterized radiative fluxes, knowledge of the inherent model uncertainties is important. In this study we evaluate one parameterization of clear-sky direct, diffuse and global shortwave downward radiation (SDR) and diverse parameterizations of clear-sky and all-sky longwave downward radiation (LDR). In a first step, SDR is estimated based on measured input variables and estimated atmospheric parameters for hourly time steps during the years 1996 to 2008. Model behaviour is validated using the high quality measurements of six Alpine Surface Radiation Budget (ASRB) stations in Switzerland covering different elevations, and measurements of the Swiss Alpine Climate Radiation Monitoring network (SACRaM) in Payerne. In a next step, twelve clear-sky LDR parameterizations are calibrated using the ASRB measurements. One of the best performing parameterizations is elected to estimate all-sky LDR, where cloud transmissivity is estimated using measured and modeled global SDR during daytime. In a last step, the performance of several interpolation methods is evaluated to determine the cloud transmissivity in the night. We show that clear-sky direct, diffuse and global SDR is adequately represented by the model when using measurements of the atmospheric parameters precipitable water and aerosol content at Payerne. If the atmospheric parameters are estimated and used as a fix value, the relative mean bias deviance (MBD) and the relative root mean squared deviance (RMSD) of the clear-sky global SDR scatter between between -2 and 5%, and 7 and 13% within the six locations. The small errors in clear-sky global SDR can be attributed to compensating effects of modeled direct and diffuse SDR since an overestimation of aerosol content in the atmosphere results in underestimating the direct, but overestimating the diffuse SDR. Calibration of LDR parameterizations to local conditions reduces MBD and RMSD strongly compared to using the published values of the parameters, resulting in relative MBD and RMSD of less than 5% respectively 10% for the best parameterizations. The best results to estimate cloud transmissivity during nighttime were obtained by linearly interpolating the average of the cloud transmissivity of the four hours of the preceeding afternoon and the following morning. Model uncertainty can be caused by different errors such as code implementation, errors in input data and in estimated parameters, etc. The influence of the latter (errors in input data and model parameter uncertainty) on model outputs is determined using Monte Carlo. Model uncertainty is provided as the relative standard deviation σrel of the simulated frequency distributions of the model outputs. An optimistic estimate of the relative uncertainty σrel resulted in 10% for the clear-sky direct, 30% for diffuse, 3% for global SDR, and 3% for the fitted all-sky LDR.

A numerical experiment on light pollution from distant sources

NASA Astrophysics Data System (ADS)

Kocifaj, M.

2011-08-01

To predict the light pollution of the night-time sky realistically over any location or measuring point on the ground presents quite a difficult calculation task. Light pollution of the local atmosphere is caused by stray light, light loss or reflection of artificially illuminated ground objects or surfaces such as streets, advertisement boards or building interiors. Thus it depends on the size, shape, spatial distribution, radiative pattern and spectral characteristics of many neighbouring light sources. The actual state of the atmospheric environment and the orography of the surrounding terrain are also relevant. All of these factors together influence the spectral sky radiance/luminance in a complex manner. Knowledge of the directional behaviour of light pollution is especially important for the correct interpretation of astronomical observations. From a mathematical point of view, the light noise or veil luminance of a specific sky element is given by a superposition of scattered light beams. Theoretical models that simulate light pollution typically take into account all ground-based light sources, thus imposing great requirements on CPU and MEM. As shown in this paper, a contribution of distant sources to the light pollution might be essential under specific conditions of low turbidity and/or Garstang-like radiative patterns. To evaluate the convergence of the theoretical model, numerical experiments are made for different light sources, spectral bands and atmospheric conditions. It is shown that in the worst case the integration limit is approximately 100 km, but it can be significantly shortened for light sources with cosine-like radiative patterns.

Characterization of a Double Mesospheric Bore Over Europe

NASA Astrophysics Data System (ADS)

Smith, Steven M.; Stober, Gunter; Jacobi, Christoph; Chau, Jorge L.; Gerding, Michael; Mlynczak, Martin G.; Russell, James M.; Baumgardner, Jeffrey L.; Mendillo, Michael; Lazzarin, Monica; Umbriaco, Gabriel

2017-09-01

Observations of a pair of mesospheric bore disturbances that propagated through the nighttime mesosphere over Europe are presented. The observations were made at the Padua Observatory, Asiago (45.9°N, 11.5°E), by the Boston University all-sky imager on 11 March 2013. The bores appeared over the northwest horizon, approximately 30 min apart, and propagated toward the southeast. Using additional satellite and radar data, we present evidence indicating the bores originated in the mesosphere from a single, larger-scale mesospheric disturbance propagating through the mesopause region. Furthermore, the large-scale mesospheric disturbance appeared to be associated with an intense weather disturbance that moved southeastward over the United Kingdom and western Europe during 10 and 11 March.

Evidence of the Dampening Effect of Dense E-region Structures on E-F Coupling

NASA Astrophysics Data System (ADS)

Helmboldt, J.

2012-12-01

Results from a combination of instruments including ionosondes, GPS receivers, the Very Large Array (VLA), and the Long Wavelength Array (LWA) are used to demonstrate the role structure within the E-region plays in coupling between instabilities within the E and F regions at midlatitudes. VLA observations of cosmic sources at 74 MHz during summer nighttime in 2002 detected northwest-to-southeast aligned wavefronts, consistent with medium-scale traveling ionospheric disturbances (MSTIDs). These waves were only found when contemporaneous observations from nearby ionosondes detected echoes from sporadic-E layers. However, when the peak density of these layers was high (foEs> 3 MHz), there were no MSTIDs detected. Similar results are presented using the first station of the LWA, LWA1, to perform all-sky imaging of dense E-region structures (sporadic-E "clouds") via coherent scattering of distant analog TV broadcasts at 55 MHz. These observations were conducted during summer/autumn 2012 and include simultaneous GPS-based observations of F-region disturbances.Left: LWA1 all-sky image of ionospheric echoes of analog TV transmissions at 55.25 MHz. Right: Doppler speed maps for the brightest echoes.

The Two Moons of Mars As Seen from 'Husband Hill'

NASA Technical Reports Server (NTRS)

2005-01-01

Taking advantage of extra solar energy collected during the day, NASA's Mars Exloration Rover Spirit settled in for an evening of stargazing, photographing the two moons of Mars as they crossed the night sky. Spirit took this succession of images at 150-second intervals from a perch atop 'Husband Hill' in Gusev Crater on martian day, or sol, 594 (Sept. 4, 2005), as the faster-moving martian moon Phobos was passing Deimos in the night sky. Phobos is the brighter object on the left and Deimos is the dimmer object on the right. The bright star Aldebaran and some other stars in the constellation Taurus are visible as star trails. Most of the other streaks in the image are the result of cosmic rays lighting up random groups of pixels in the camera.

Scientists will use images of the two moons to better map their orbital positions, learn more about their composition, and monitor the presence of nighttime clouds or haze. Spirit took the five images that make up this c omposite with its panoramic camera using the camera's broadband filter, which was designed specifically for acquiring images under low-light conditions.

A Dynamic Enhancement With Background Reduction Algorithm: Overview and Application to Satellite-Based Dust Storm Detection

NASA Astrophysics Data System (ADS)

Miller, Steven D.; Bankert, Richard L.; Solbrig, Jeremy E.; Forsythe, John M.; Noh, Yoo-Jeong; Grasso, Lewis D.

2017-12-01

This paper describes a Dynamic Enhancement Background Reduction Algorithm (DEBRA) applicable to multispectral satellite imaging radiometers. DEBRA uses ancillary information about the clear-sky background to reduce false detections of atmospheric parameters in complex scenes. Applied here to the detection of lofted dust, DEBRA enlists a surface emissivity database coupled with a climatological database of surface temperature to approximate the clear-sky equivalent signal for selected infrared-based multispectral dust detection tests. This background allows for suppression of false alarms caused by land surface features while retaining some ability to detect dust above those problematic surfaces. The algorithm is applicable to both day and nighttime observations and enables weighted combinations of dust detection tests. The results are provided quantitatively, as a detection confidence factor [0, 1], but are also readily visualized as enhanced imagery. Utilizing the DEBRA confidence factor as a scaling factor in false color red/green/blue imagery enables depiction of the targeted parameter in the context of the local meteorology and topography. In this way, the method holds utility to both automated clients and human analysts alike. Examples of DEBRA performance from notable dust storms and comparisons against other detection methods and independent observations are presented.

The Two Moons of Mars as Seen from Mars

NASA Technical Reports Server (NTRS)

2005-01-01

Taking advantage of extra solar energy collected during the day, NASA's Mars Exploration Rover Spirit settled in for an evening of stargazing, photographing the two moons of Mars as they crossed the night sky. 'It is incredibly cool to be running an observatory on another planet,' said planetary scientist Jim Bell of Cornell University, Ithaca, N.Y., lead scientist for the panoramic cameras on Spirit and Opportunity. This time-lapse composite, acquired the evening of Spirit's martian sol 585 (Aug. 26, 2005) from a perch atop 'Husband Hill' in Gusev Crater, shows Phobos, the brighter moon, on the right, and Deimos, the dimmer moon, on the left. Tiny streaks mark the trails of background stars moving across the sky or the impact of cosmic rays lighting up random groups of pixels in the image.

Scientists will use images of the two moons to better map their orbital positions, learn more about their composition, and monitor the presence of nighttime clouds or haze. Spirit took the five images that make up this composite using the panoramic camera's broadband filter, which was designed specifically for acquiring images under low-light conditions.

Reducing the ecological consequences of night-time light pollution: options and developments

PubMed Central

Gaston, Kevin J; Davies, Thomas W; Bennie, Jonathan; Hopkins, John

2012-01-01

1. Much concern has been expressed about the ecological consequences of night-time light pollution. This concern is most often focused on the encroachment of artificial light into previously unlit areas of the night-time environment, but changes in the spectral composition, duration and spatial pattern of light are also recognized as having ecological effects. 2. Here, we examine the potential consequences for organisms of five management options to reduce night-time light pollution. These are to (i) prevent areas from being artificially lit; (ii) limit the duration of lighting; (iii) reduce the ‘trespass’ of lighting into areas that are not intended to be lit (including the night sky); (iv) change the intensity of lighting; and (v) change the spectral composition of lighting. 3. Maintaining and increasing natural unlit areas is likely to be the most effective option for reducing the ecological effects of lighting. However, this will often conflict with other social and economic objectives. Decreasing the duration of lighting will reduce energy costs and carbon emissions, but is unlikely to alleviate many impacts on nocturnal and crepuscular animals, as peak times of demand for lighting frequently coincide with those in the activities of these species. Reducing the trespass of lighting will maintain heterogeneity even in otherwise well-lit areas, providing dark refuges that mobile animals can exploit. Decreasing the intensity of lighting will reduce energy consumption and limit both skyglow and the area impacted by high-intensity direct light. Shifts towards ‘whiter’ light are likely to increase the potential range of environmental impacts as light is emitted across a broader range of wavelengths. 4. Synthesis and applications. The artificial lightscape will change considerably over coming decades with the drive for more cost-effective low-carbon street lighting solutions and growth in the artificially lit area. Developing lighting strategies that minimize adverse ecological impacts while balancing the often conflicting requirements of light for human utility, comfort and safety, aesthetic concerns, energy consumption and carbon emission reduction constitute significant future challenges. However, as both lighting technology and understanding of its ecological effects develop, there is potential to identify adaptive solutions that resolve these conflicts. PMID:23335816

Reducing the ecological consequences of night-time light pollution: options and developments.

PubMed

Gaston, Kevin J; Davies, Thomas W; Bennie, Jonathan; Hopkins, John

2012-12-01

1. Much concern has been expressed about the ecological consequences of night-time light pollution. This concern is most often focused on the encroachment of artificial light into previously unlit areas of the night-time environment, but changes in the spectral composition, duration and spatial pattern of light are also recognized as having ecological effects.2. Here, we examine the potential consequences for organisms of five management options to reduce night-time light pollution. These are to (i) prevent areas from being artificially lit; (ii) limit the duration of lighting; (iii) reduce the 'trespass' of lighting into areas that are not intended to be lit (including the night sky); (iv) change the intensity of lighting; and (v) change the spectral composition of lighting.3. Maintaining and increasing natural unlit areas is likely to be the most effective option for reducing the ecological effects of lighting. However, this will often conflict with other social and economic objectives. Decreasing the duration of lighting will reduce energy costs and carbon emissions, but is unlikely to alleviate many impacts on nocturnal and crepuscular animals, as peak times of demand for lighting frequently coincide with those in the activities of these species. Reducing the trespass of lighting will maintain heterogeneity even in otherwise well-lit areas, providing dark refuges that mobile animals can exploit. Decreasing the intensity of lighting will reduce energy consumption and limit both skyglow and the area impacted by high-intensity direct light. Shifts towards 'whiter' light are likely to increase the potential range of environmental impacts as light is emitted across a broader range of wavelengths.4.Synthesis and applications. The artificial lightscape will change considerably over coming decades with the drive for more cost-effective low-carbon street lighting solutions and growth in the artificially lit area. Developing lighting strategies that minimize adverse ecological impacts while balancing the often conflicting requirements of light for human utility, comfort and safety, aesthetic concerns, energy consumption and carbon emission reduction constitute significant future challenges. However, as both lighting technology and understanding of its ecological effects develop, there is potential to identify adaptive solutions that resolve these conflicts.

Determining Light Pollution of the Global Sky: GLOBE at Night

NASA Astrophysics Data System (ADS)

Henderson, S.; Meymaris, K.; Ward, D.; Walker, C.; Russell, R.; Pompea, S.; Salisbury, D.

2006-05-01

GLOBE at Night is an international science event designed to observe and record the visible stars as a means of measuring light pollution in a given location. Increased and robust understanding of our environment requires learning opportunities that take place outside of the conventional K-12 classroom and beyond the confines of the school day. This hands-on learning activity extended the traditional classroom and school day last March with a week of nighttime sky observations involving teachers, students and their families. The quality of the night sky for stellar observations is impacted by several factors including human activities. By observing cloud cover and locating specific constellations in the sky, students from around the world learned how the lights in their community contribute to light pollution, exploring the relationship between science, technology and their society. Students learned that light pollution impacts more than just the visibility of stars at night. Lights at night impact both the biology and ecology of many species in our environment. Students were able to participate in this global scientific campaign by submitting their observations through an online database, allowing for authentic worldwide research and analysis by participating scientists. Students and their families learned how latitude and longitude coordinates provide a location system to map and analyze the observation data submitted from around the globe. The collected data is available online for use by students, teachers and scientists worldwide to assess how the quality of the night sky varies around the world. This session will share how students and scientists across the globe can explore and analyze the results of this exciting campaign. GLOBE at Night is a collaborative effort sponsored by The GLOBE Program, the National Optical Astronomy Observatory (NOAO), Centro de Apoyo a la Didactica de la Astronomia (CADIAS), Windows to the Universe, and ESRI. The GLOBE Program is an international inquiry-based program designed to engage teachers with their students in partnership with research scientists to better understand the environment at local, regional, and global scales. The GLOBE Program is managed by the University Corporation for Atmospheric Research and Colorado State University with funding from NASA, NSF, and the U.S. Department of State.

Light Pollution: The Global View

NASA Astrophysics Data System (ADS)

Schwarz, H. E.

2003-04-01

It is only since recent years that the importance of the effects of outdoor lighting on the night-time environment and on the physical and mental health of humans is recognized on a wider scale. The related issue of light pollution is a particularly complex one, with potential conflicts of interest between the utilities, environmentalists, astronomers, the lighting industry and various government departments. Energy politics are always a sensitive issue, and light pollution is no exception to this rule. The effects of light pollution on flora, fauna -including humans and their widely varying night-time activities- are often subtle and need extensive field studies to be quantified in a sensible manner. The present conference, initiated by Commission 50 of the International Astronomical Union, is an attempt to bring together the astronomical community, the lighting industry, end-users, the utilities, and public authorities for a discussion and an exchange of ideas and information that will create goodwill among these groups and will thus contribute to making the global efforts to reduce pollution more efficient and effective. Radio frequency pollution was also discussed in the context of radio astronomy and its efforts to create radio-quiet zones in collaboration with the government authorities that allocate frequency bands to the various users -mainly the telecommunications industry- and to protect the major planned and present radio observatories of the world. The 3-day conference was attended by more than 130 representatives from 12 countries of all the above-mentioned groups, and a wide range of topics was discussed. Some of the highlights were: The presentation of the 1st world atlas of artificial night sky brightness (Cinzano et al.); the article by the International Darksky Association on their world-wide efforts to curb light pollution (Alvarez del Castillo et al.); the laws controlling light pollution implemented in Spain (Diaz et al.) and Chile (Sanhueza et al.), an overview of the work on radio frequency protection of sites (Cohen et al.) and the excellent introduction to the topic from the Chilean point of view (Daud). Related topics in the book are light pollution education, aircraft contrails, space advertising (with an added document provided by the relevant UN commission), and an experiment on involving the population of an entire country in measuring sky brightness, by using the internet and the media. The text is aimed at professionals from a wide range of disciplines related to lighting and its effects on the night-time environment in the broadest sense of the word. Lay persons interested in this emerging multi-disciplinary field can also find much of interest in this book. Link: http://www.wkap.nl/prod/b/1-4020-1174-1

Cloud Climatology for Land Stations Worldwide, 1971-2009 (NDP-026D)

DOE Data Explorer

Hahn, C. J. [University of Arizona; Warren, S. G. [University of Washington; Eastman, R. [University of Washington

2012-08-01

Surface synoptic weather reports for 39 years have been processed to provide a climatology of clouds for each of over 5000 land-based weather stations with long periods of record both day and night. For each station, this digital archive includes: multi-year annual, seasonal and monthly averages for day and night separately; seasonal and monthly averages by year; averages for eight times per day; and analyses of the first harmonic for the annual and diurnal cycles. Averages are given for total cloud cover, clear-sky frequency, and 9 cloud types: 5 in the low level (fog, St, Sc, Cu, Cb), 3 in the middle level (Ns, As, Ac) and one in the high level (all cirriform clouds combined). Cloud amounts and frequencies of occurrence are given for all types. In addition, non-overlapped amounts are given for middle and high cloud types, and average base heights are given for low cloud types. Nighttime averages were obtained by using only those reports that met an "illuminance criterion" (i.e., made under adequate moonlight or twilight), thus making possible the determination of diurnal cycles and nighttime trends for cloud types.The authors have also produced an online, gridded atlas of the cloud observations contained in NDP-026D. The Online Cloud Atlas containing NDP-026D data is available via the University of Washington.

S4EI (Spectral Sampling with Slicer for Stellar and Extragalactical Instrumentation), a new-generation of 3D spectro-imager dedicated to night astronomy

NASA Astrophysics Data System (ADS)

Sayède, Frédéric; Puech, Mathieu; Mein, Pierre; Bonifacio, Piercarlo; Malherbe, Jean-Marie; Galicher, Raphaël.; Amans, Jean-Philippe; Fasola, Gilles

2014-07-01

Multichannel Subtractive Double Pass (MSDP) spectrographs have been widely used in solar spectroscopy because of their ability to provide an excellent compromise between field of view and spatial and spectral resolutions. Compared with other types of spectrographs, MSDP can deliver simultaneous monochromatic images at higher spatial and spectral resolutions without any time-scanning requirement (as with Fabry-Perot spectrographs), and with limited loss of flux. These performances are obtained thanks to a double pass through the dispersive element. Recent advances with VPH (Volume phase holographic) Grisms as well as with image slicers now make MSDP potentially sensitive to much smaller fluxes. We present S4EI (Spectral Sampling with Slicer for Stellar and Extragalactical Instrumentation), which is a new concept for extending MSDP to night-time astronomy. It is based on new generation reflecting plane image slicers working with large apertures specific to night-time telescopes. The resulting design could be potentially very attractive and innovative for different domains of astronomy, e.g., the simultaneous spatial mapping of accurately flux-calibrated emission lines between OH sky lines in extragalactic astronomy or the simultaneous imaging of stars, exoplanets and interstellar medium. We present different possible MSDP/S4EI configurations for these science cases and expected performances on telescopes such as the VLT.

A gap-filling model for eddy covariance latent heat flux: Estimating evapotranspiration of a subtropical seasonal evergreen broad-leaved forest as an example

NASA Astrophysics Data System (ADS)

Chen, Yi-Ying; Chu, Chia-Ren; Li, Ming-Hsu

2012-10-01

SummaryIn this paper we present a semi-parametric multivariate gap-filling model for tower-based measurement of latent heat flux (LE). Two statistical techniques, the principal component analysis (PCA) and a nonlinear interpolation approach were integrated into this LE gap-filling model. The PCA was first used to resolve the multicollinearity relationships among various environmental variables, including radiation, soil moisture deficit, leaf area index, wind speed, etc. Two nonlinear interpolation methods, multiple regressions (MRS) and the K-nearest neighbors (KNNs) were examined with random selected flux gaps for both clear sky and nighttime/cloudy data to incorporate into this LE gap-filling model. Experimental results indicated that the KNN interpolation approach is able to provide consistent LE estimations while MRS presents over estimations during nighttime/cloudy. Rather than using empirical regression parameters, the KNN approach resolves the nonlinear relationship between the gap-filled LE flux and principal components with adaptive K values under different atmospheric states. The developed LE gap-filling model (PCA with KNN) works with a RMSE of 2.4 W m-2 (˜0.09 mm day-1) at a weekly time scale by adding 40% artificial flux gaps into original dataset. Annual evapotranspiration at this study site were estimated at 736 mm (1803 MJ) and 728 mm (1785 MJ) for year 2008 and 2009, respectively.

Cloud Screening and Quality Control Algorithm for Star Photometer Data: Assessment with Lidar Measurements and with All-sky Images

NASA Technical Reports Server (NTRS)

Ramirez, Daniel Perez; Lyamani, H.; Olmo, F. J.; Whiteman, D. N.; Navas-Guzman, F.; Alados-Arboledas, L.

2012-01-01

This paper presents the development and set up of a cloud screening and data quality control algorithm for a star photometer based on CCD camera as detector. These algorithms are necessary for passive remote sensing techniques to retrieve the columnar aerosol optical depth, delta Ae(lambda), and precipitable water vapor content, W, at nighttime. This cloud screening procedure consists of calculating moving averages of delta Ae() and W under different time-windows combined with a procedure for detecting outliers. Additionally, to avoid undesirable Ae(lambda) and W fluctuations caused by the atmospheric turbulence, the data are averaged on 30 min. The algorithm is applied to the star photometer deployed in the city of Granada (37.16 N, 3.60 W, 680 ma.s.l.; South-East of Spain) for the measurements acquired between March 2007 and September 2009. The algorithm is evaluated with correlative measurements registered by a lidar system and also with all-sky images obtained at the sunset and sunrise of the previous and following days. Promising results are obtained detecting cloud-affected data. Additionally, the cloud screening algorithm has been evaluated under different aerosol conditions including Saharan dust intrusion, biomass burning and pollution events.

Association between nighttime artificial light pollution and sea turtle nest density along Florida coast: A geospatial study using VIIRS remote sensing data.

PubMed

Hu, Zhiyong; Hu, Hongda; Huang, Yuxia

2018-08-01

Artificial lighting at night has becoming a new type of pollution posing an important anthropogenic environmental pressure on organisms. The objective of this research was to examine the potential association between nighttime artificial light pollution and nest densities of the three main sea turtle species along Florida beaches, including green turtles, loggerheads, and leatherbacks. Sea turtle survey data was obtained from the "Florida Statewide Nesting Beach Survey program". We used the new generation of satellite sensor "Visible Infrared Imaging Radiometer Suite (VIIRS)" (version 1 D/N Band) nighttime annual average radiance composite image data. We defined light pollution as artificial light brightness greater than 10% of the natural sky brightness above 45° of elevation (>1.14 × 10 -11 Wm -2 sr -1 ). We fitted a generalized linear model (GLM), a GLM with eigenvectors spatial filtering (GLM-ESF), and a generalized estimating equations (GEE) approach for each species to examine the potential correlation of nest density with light pollution. Our models are robust and reliable in terms of the ability to deal with data distribution and spatial autocorrelation (SA) issues violating model assumptions. All three models found that nest density is significantly negatively correlated with light pollution for each sea turtle species: the higher light pollution, the lower nest density. The two spatially extended models (GLM-ESF and GEE) show that light pollution influences nest density in a descending order from green turtles, to loggerheads, and then to leatherbacks. The research findings have an implication for sea turtle conservation policy and ordinance making. Near-coastal lights-out ordinances and other approaches to shield lights can protect sea turtles and their nests. The VIIRS DNB light data, having significant improvements over comparable data by its predecessor, the DMSP-OLS, shows promise for continued and improved research about ecological effects of artificial light pollution. Copyright © 2018 Elsevier Ltd. All rights reserved.

Remote sensing of thermal radiation from an aircraft - An analysis and evaluation of crop-freeze protection methods

NASA Technical Reports Server (NTRS)

Sutherland, R. A.; Hannah, H. E.; Cook, A. F.; Martsolf, J. D.

1981-01-01

Thermal images from an aircraft-mounted scanner are used to evaluate the effectiveness of crop-freeze protection devices. Data from flights made while using fuel oil heaters, a wind machine and an undercanopy irrigation system are compared. Results show that the overall protection provided by irrigation (at approximately 2 C) is comparable to the less energy-efficient heater-wind machine combination. Protection provided by the wind machine alone (at approximately 1 C) was found to decrease linearly with distance from the machine by approximately 1 C/100 m. The flights were made over a 1.5 hectare citrus grove at an altitude of 450 m with an 8-14 micron detector. General meteorological conditions during the experiments, conducted during the nighttime, were cold (at approximately -6 C) and calm with clear skies.

Rapid approach to the quantitative determination of nocturnal ground irradiance in populated territories: a clear-sky case

NASA Astrophysics Data System (ADS)

Kocifaj, Miroslav; Petržala, Jaromír

2016-11-01

A zero-order approach to the solving of the radiative transfer equation and a method for obtaining the horizontal diffuse irradiance at night-time are both developed and intended for wide use in numerical predictions of nocturnal ground irradiance in populated territories. Downward diffuse radiative fluxes are computed with a two-stream approximation, and the data products obtained are useful for scientists who require rapid estimations of illumination levels during the night. The rapid technique presented here is especially important when the entire set of calculations is to be repeated for different lighting technologies and/or radiant intensity distributions with the aim of identifying high-level illuminance/irradiance, the spectral composition of scattered light or other optical properties of diffuse light at the ground level. The model allows for the computation of diffuse horizontal irradiance due to light emissions from ground-based sources with arbitrary spectral compositions. The optical response of a night sky is investigated using the ratio of downward to upward irradiance, R⊥, λ(0). We show that R⊥, λ(0) generally peaks at short wavelengths, thus suggesting that, e.g., the blue light of an LED lamp would make the sky even more bluish. However, this effect can be largely suppressed or even removed with the spectral sensitivity function of the average human eye superimposed on to the lamp spectrum. Basically, blue light scattering dominates at short optical distances, while red light is transmitted for longer distances and illuminates distant places. Computations are performed for unshielded as well as fully shielded lights, while the spectral function R⊥, λ(0) is tabulated to make possible the modelling of various artificial lights, including those not presented here.

The Atacama Cosmology Telescope: Two-season spectrum and parameters

NASA Astrophysics Data System (ADS)

Hlozek, Renée; Louis, Thibaut; Grace, Emily; Hasselfield, Matthew; Lungu, Marius; Maurin, Loic; Atacama Cosmology Telescope

2017-01-01

We present the temperature and polarization angular power spectra measured by the Atacama Cosmology Telescope polarimeter (ACTPol) over 548 deg^2 of sky on the celestial Equator, from nighttime data collected during 2013-14 using two kilo-detector arrays at 146 GHz. We use these spectra, and the spectra measured with the MBAC camera on ACT from 2008-10, in combination with Planck and WMAP satellite data to estimate cosmological parameters from the temperature, polarization, and temperature-polarization cross-correlations. We find the new ACTPol data to be consistent with the ΛCDM model. The ACTPol temperature-polarization cross-spectrum now provides stronger constraints on multiple parameters than the ACTPol temperature power spectrum, including the baryon density and the acoustic peak position angle, and the derived Hubble constant. Adding the new data to Planck temperature data tightens the limits on damping tail parameters, which we present here.

International Year of Astronomy Events in a Small, Midwestern Community

NASA Astrophysics Data System (ADS)

Brevik, C. E.

2009-12-01

Dickinson State University is a small, liberal arts college located in Southwestern North Dakota. With extremely dark skies and a safe, family-friendly nighttime environment, this rural location provides excellent opportunities for clear astronomical viewing. However, the university does not offer a physics or an astronomy major. Therefore, a concentrated effort was needed to develop a trained workforce of interested college students who could help manage public viewing sessions. Once oriented to the fundamentals of telescope viewing, this group of students offered numerous community-related activities to support the International Year of Astronomy. These efforts, designed to share the excitement of the universe with kids and adults alike, included a variety of events such as public presentations and star parties. The star parties were aided by the purchase of a 14” automated Cassegrain telescope funded by a grant from the North Dakota Space Grant Consortium.

NGSLR's Measurement of the Retro-Reflector Array Response of Various LEO to GNSS Satellites

NASA Technical Reports Server (NTRS)

McGarry, Jan; Clarke, Christopher; Degnan, John; Donovan, Howard; Hall, Benjamin; Hovarth, Julie; Zagwodzki, Thomas

2012-01-01

"NASA's Next Generation Satellite Laser Ranging System (NGSLR) has successfully demonstrated daylight and nighttime tracking this year to s atellites from LEO to GNSS orbits, using a 7-8 arcsecond beam divergence, a 43% QE Hamamatsu MCP-PMT with single photon detection, a narrow field of view (11 arcseconds), and a 1 mJ per pulse 2kHz repetition rate laser. We have compared the actual return rates we are getting against the theoretical link calculations, using the known system confi guration parameters, an estimate of the sky transmission using locall y measured visibility, and signal processing to extract the signal from the background noise. We can achieve good agreement between theory and measurement in most passes by using an estimated pOinting error. We will s.()w the results of this comparison along with our conclusio ns."

The widetilde{A}←widetilde{X} ABSORPTION SPECTRUM OF 2-NITROOXYBUTYL PEROXY RADICAL

NASA Astrophysics Data System (ADS)

Eddingsaas, Nathan; Takematsu, Kana; Okumura, Mitchio

2009-06-01

The nitrate radical is an important atmospheric oxidant in the nighttime sky. Nitrate radicals react by addition to alkenes, and in the presence of oxygen form nitrooxyalkyl peroxy radicals. The peroxy radical formed from the reaction of 2-butene, nitrate radical, and oxygen was detected by cavity ringdown spectroscopy (CRDS) via its widetilde{A}←widetilde{X} electronic absorption spectrum. The widetilde{A}←widetilde{X} electronic transition is a bound-bound transition with enough structure to distinguish between different peroxy radicals as well as different conformers of the same peroxy radical. Two conformers of the nitrooxybutyl peroxy radical have been observed; the absorption features are red shifted from the same absorption features of sec-butyl peroxy radical. Calculations on the structure of nitrooxyalkyl peroxy radicals and general trends of the position of the widetilde{A}←widetilde{X} absorption transitions have also been performed and compared to those of unsubstituted peroxy radicals.

The influence of night-time hypertension on left ventricular mechanics.

PubMed

Tadic, Marijana; Cuspidi, Cesare; Pencic-Popovic, Biljana; Celic, Vera; Mancia, Giuseppe

2017-09-15

The aim of this study was to evaluate left ventricular (LV) mechanics in individuals with daytime, night-time and day-nighttime hypertension. This cross-sectional study included 272 untreated subjects who underwent 24-hour ambulatory blood pressure monitoring and complete two-dimensional echocardiographic examination including strain analysis. According to current guidelines, night-time hypertension was defined as nocturnal systolic blood pressure≥120mmHg and/or diastolic blood pressure≥70mmHg and day-time hypertension as systolic blood pressure≥135mmHg and/or diastolic blood pressure≥85mmHg. The study sample included 61 normotensive subjects (22%), 77 isolated daytime hypertension (28%), 40 isolated night-time hypertension (15%) and 94day-nighttime hypertension (35%). LV longitudinal and circumferential strain gradually and significantly decreased from normotensive subjects across patients with isolated daytime and night-time hypertension to hypertensive individuals with persistent hypertension. Radial strain was similar between the observed groups. LV twist increased from normotensive subjects across isolated daytime and night-time hypertensive patients to day-nighttime hypertensive individuals. Hypertensive patients with day-nighttime and night-time hypertension are significantly more associated with decreased longitudinal and circumferential strain than hypertensive patients with isolated day-time hypertension and normotension. LV mechanics gradually deteriorated from normotensive controls, across isolated day- and night-time hypertension, to day-nighttime hypertension. Patients with night-time and day-nighttime hypertension are associated with higher risk of LV mechanical dysfunction than normotensives and day-time hypertensives. Copyright © 2017 Elsevier B.V. All rights reserved.

A Gridded Climatology of Clouds over Land (1971-1996) and Ocean (1954-2008) from Surface Observations Worldwide (NDP-026E)*

DOE Data Explorer

Hahn, C. J. [University of Arizona; Warren, S. G. [University of Washington

2007-01-01

Surface synoptic weather reports from ships and land stations worldwide were processed to produce a global cloud climatology which includes: total cloud cover, the amount and frequency of occurrence of nine cloud types within three levels of the troposphere, the frequency of occurrence of clear sky and of precipitation, the base heights of low clouds, and the non-overlapped amounts of middle and high clouds. Synoptic weather reports are made every three hours; the cloud information in a report is obtained visually by human observers. The reports used here cover the period 1971-96 for land and 1954-2008 for ocean. This digital archive provides multi-year monthly, seasonal, and annual averages in 5x5-degree grid boxes (or 10x10-degree boxes for some quantities over the ocean). Daytime and nighttime averages, as well as the diurnal average (average of day and night), are given. Nighttime averages were computed using only those reports that met an "illuminance criterion" (i.e., made under adequate moonlight or twilight), thus minimizing the "night-detection bias" and making possible the determination of diurnal cycles and nighttime trends for cloud types. The phase and amplitude of the first harmonic of both the diurnal cycle and the annual cycle are given for the various cloud types. Cloud averages for individual years are also given for the ocean for each of 4 seasons, and for each of the 12 months (daytime-only averages for the months). [Individual years for land are not gridded, but are given for individual stations in a companion data set, CDIAC's NDP-026D).] This analysis used 185 million reports from 5388 weather stations on continents and islands, and 50 million reports from ships; these reports passed a series of quality-control checks. This analysis updates (and in most ways supercedes) the previous cloud climatology constructed by the authors in the 1980s. Many of the long-term averages described here are mapped on the University of Washington, Department of Atmospheric Sciences Web site. The Online Cloud Atlas containing NDP-026E data is available via the University of Washington.

Evaluation of the WRF-Urban Modeling System Coupled to Noah and Noah-MP Land Surface Models Over a Semiarid Urban Environment

NASA Astrophysics Data System (ADS)

Salamanca, Francisco; Zhang, Yizhou; Barlage, Michael; Chen, Fei; Mahalov, Alex; Miao, Shiguang

2018-03-01

We have augmented the existing capabilities of the integrated Weather Research and Forecasting (WRF)-urban modeling system by coupling three urban canopy models (UCMs) available in the WRF model with the new community Noah with multiparameterization options (Noah-MP) land surface model (LSM). The WRF-urban modeling system's performance has been evaluated by conducting six numerical experiments at high spatial resolution (1 km horizontal grid spacing) during a 15 day clear-sky summertime period for a semiarid urban environment. To assess the relative importance of representing urban surfaces, three different urban parameterizations are used with the Noah and Noah-MP LSMs, respectively, over the two major cities of Arizona: Phoenix and Tucson metropolitan areas. Our results demonstrate that Noah-MP reproduces somewhat better than Noah the daily evolution of surface skin temperature and near-surface air temperature (especially nighttime temperature) and wind speed. Concerning the urban areas, bulk urban parameterization overestimates nighttime 2 m air temperature compared to the single-layer and multilayer UCMs that reproduce more accurately the daily evolution of near-surface air temperature. Regarding near-surface wind speed, only the multilayer UCM was able to reproduce realistically the daily evolution of wind speed, although maximum winds were slightly overestimated, while both the single-layer and bulk urban parameterizations overestimated wind speed considerably. Based on these results, this paper demonstrates that the new community Noah-MP LSM coupled to an UCM is a promising physics-based predictive modeling tool for urban applications.

Time-dependent effects of dim light at night on re-entrainment and masking of hamster activity rhythms.

PubMed

Frank, David W; Evans, Jennifer A; Gorman, Michael R

2010-04-01

Bright light has been established as the most ubiquitous environmental cue that entrains circadian timing systems under natural conditions. Light equivalent in intensity to moonlight (<1 lux), however, also strongly modulates circadian function in a number of entrainment paradigms. For example, compared to completely dark nights, dim nighttime illumination accelerated re-entrainment of hamster activity rhythms to 4-hour phase advances and delays of an otherwise standard laboratory photocycle. The purpose of this study was to determine if a sensitive period existed in the night during which dim illumination had a robust influence on speed of re-entrainment. Male Siberian hamsters were either exposed to dim light throughout the night, for half of the night, or not at all. Compared to dark nights, dim illumination throughout the entire night decreased by 29% the time for the midpoint of the active phase to re-entrain to a 4-hour phase advance and by 26% for a 4-hour delay. Acceleration of advances and delays were also achieved with 5 hours of dim light per night, but effects depended on whether dim light was present in the first half, second half, or first and last quarters of the night. Both during phase shifting and steady-state entrainment, partially lit nights also produced strong positive and negative masking effects, as well as entrainment aftereffects in constant darkness. Thus, even in the presence of a strong zeitgeber, light that might be encountered under a natural nighttime sky potently modulates the circadian timing system of hamsters.

The summer urban heat island of Bucharest (Romania) as retrieved from satellite imagery

NASA Astrophysics Data System (ADS)

Cheval, Sorin; Dumitrescu, Alexandru

2014-05-01

The summer Urban Heat Island (UHI) of the city of Bucharest (Romania) has been investigated in terms of its shape, intensity, extension, and links to land cover. The study integrates land surface temperature (LST) data retrieved by the MODIS sensors aboard the Terra and Aqua NASA satellites, and SEVIRI sensors on board of the geostationary platform MSG, along 2000-2012. Based on the Rodionov Regime Shift Index, the significant changing points in the land surface temperature values along transverse profiles crossing the city's centre were considered as UHI's limits. The study shows that the intensity calculated as the difference between the LST within the UHI limits and several surrounding buffers is an objective and flexible tool for describing the average thermal state of the urban-rural transition. The method secures the weight of comparing the UHI's intensity of different urban areas. There are little variations from one month to another, but UHI's shapes and intensities under clear-sky conditions are very specific to nighttime (more regular and 2-3°C less in the 7-km width buffer), and daytime (more twisted and more steep temperature decrease). For both cases, strong relationships with the land cover can be assumed. The nighttime UHI's geometry is more regular, and the intensity lower than the day situation, while the land cover exerts a strong influence on the Bucharest LST. After all, the study promotes an objective manner to delimitate and quantify the UHI based on satellite imagery. The study was performed within the STAR project 92/2013 (Urban Heat Island Monitoring under Present and Future Climate - UCLIMESA).

Results from the Prototype GLOBE at Night Worldwide Light Pollution Observation Program

NASA Astrophysics Data System (ADS)

Walker, Constance E.; Pompea, S. M.; Isbell, D.; Orellana, D.; Blurton, C.; Henderson, S.

2006-06-01

Students, families, and educators worldwide participated in GLOBE at Night - an international event designed to observe and record the visible stars as a means of measuring light pollution in a given location. Participation was open to anyone - anywhere in the world - who could get outside and look skyward during the week of March 22-29, 2006. Our goal was 5000 observations from around the world in this prototype program.The hands-on learning activities associated with the program were designed to extend the traditional classroom and school day with a week of nighttime observations involving teachers, students and their families. By locating specific constellations in the sky, students from around the world learned how the lights in their community contribute to light pollution. Students explored the different light sources in their community learning the relationship between science, technology and society, and they reported their observations online through a central database allowing for authentic worldwide research and analysis. The observations made during GLOBE at Night helped students and scientists together assess how the quality of the night sky varies around the world as well as the level of energy wastage associated with poorly-shielded lights.For more information, visit http://www.globe.gov/globeatnight.GLOBE at Night is a collaboration between The GLOBE Program, the National Optical Astronomy Observatory (NOAO), Centro de Apoyo a la Didactica de la Astronomia (CADIAS) in Chile , Windows to the Universe, and Environmental Systems Research Institute, Inc. (ESRI).

Role of persistent low-level clouds in mitigating air quality impacts of wintertime cold pool conditions

NASA Astrophysics Data System (ADS)

VanReken, Timothy M.; Dhammapala, Ranil S.; Jobson, B. Thomas; Bottenus, Courtney L.; VanderSchelden, Graham S.; Kaspari, Susan D.; Gao, Zhongming; Zhu, Qiurui; Lamb, Brian K.; Liu, Heping; Johnston, Jeff

2017-04-01

The Yakima Air Wintertime Nitrate Study (YAWNS) was conducted in January 2013 to investigate the drivers of elevated levels of fine particulate matter (PM2.5) frequently present in the region during winter stagnation periods. An extended stagnation period occurred during the study. For the first four days of the event, skies were clear and the strong diel variation in air pollution patterns were consistent with the expected effects of strong low-level nighttime temperature inversions with moderate mixing during daylight hours. Later in the event a low-level cloud layer formed that persisted over the Yakima Valley for the next seven days while regional conditions remained stagnant. Coincident with the onset of cloud, the levels of all measured primary pollutants, including CO2, CO, NOx, particle number concentration, and black carbon, dropped dramatically and remained low with negligible diel variation for as long as the cloud layer was present. The observed patterns for these air pollutants are consistent with decreased stability and enhanced mixing associated with the cloud-topped boundary layer. Interestingly, levels of secondary pollutants, most notably particulate ammonium nitrate, did not exhibit the same decline. This difference may be due to shifts in the chemical production of secondary pollutants during cloudy conditions, or may merely reflect a further influence of mixing. The results imply that the best strategies for managing wintertime air quality during episodes of persistent cloud are likely different from those needed during clear-sky stagnation events.

Physical behaviour of anthropogenic light propagation into the nocturnal environment

PubMed Central

Aubé, Martin

2015-01-01

Propagation of artificial light at night (ALAN) in the environment is now known to have non negligible consequences on fauna, flora and human health. These consequences depend on light levels and their spectral power distributions, which in turn rely on the efficiency of various physical processes involved in the radiative transfer of this light into the atmosphere and its interactions with the built and natural environment. ALAN can affect the living organisms by direct lighting and indirect lighting (scattered by the sky and clouds and/or reflected by local surfaces). This paper mainly focuses on the behaviour of the indirect light scattered under clear sky conditions. Various interaction processes between anthropogenic light sources and the natural environment are discussed. This work mostly relies on a sensitivity analysis conducted with the light pollution radiative transfer model, Illumina (Aubé et al. 2005 Light pollution modelling and detection in a heterogeneous environment: toward a night-time aerosol optical depth retrieval method. In Proc. SPIE 2005, vol. 5890, San Diego, California, USA). More specifically, the impact of (i) the molecular and aerosol scattering and absorption, (ii) the second order of scattering, (iii) the topography and obstacle blocking, (iv) the ground reflectance and (v) the spectrum of light devices and their angular emission functions are examined. This analysis considers different behaviour as a function of the distance from the city centre, along with different zenith viewing angles in the principal plane. PMID:25780231

Physical behaviour of anthropogenic light propagation into the nocturnal environment.

PubMed

Aubé, Martin

2015-05-05

Propagation of artificial light at night (ALAN) in the environment is now known to have non negligible consequences on fauna, flora and human health. These consequences depend on light levels and their spectral power distributions, which in turn rely on the efficiency of various physical processes involved in the radiative transfer of this light into the atmosphere and its interactions with the built and natural environment. ALAN can affect the living organisms by direct lighting and indirect lighting (scattered by the sky and clouds and/or reflected by local surfaces). This paper mainly focuses on the behaviour of the indirect light scattered under clear sky conditions. Various interaction processes between anthropogenic light sources and the natural environment are discussed. This work mostly relies on a sensitivity analysis conducted with the light pollution radiative transfer model, Illumina (Aubé et al. 2005 Light pollution modelling and detection in a heterogeneous environment: toward a night-time aerosol optical depth retrieval method. In Proc. SPIE 2005, vol. 5890, San Diego, California, USA). More specifically, the impact of (i) the molecular and aerosol scattering and absorption, (ii) the second order of scattering, (iii) the topography and obstacle blocking, (iv) the ground reflectance and (v) the spectrum of light devices and their angular emission functions are examined. This analysis considers different behaviour as a function of the distance from the city centre, along with different zenith viewing angles in the principal plane. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Phylogenetic and ecological patterns in nighttime transpiration among five members of the genus Rubus co-occurring in western Oregon

PubMed Central

McNellis, Brandon; Howard, Ava R

2015-01-01

Nighttime transpiration is a substantial portion of ecosystem water budgets, but few studies compare water use of closely related co-occurring species in a phylogenetic context. Nighttime transpiration can range up to 69% of daytime rates and vary between species, ecosystem, and functional type. We examined leaf-level daytime and nighttime gas exchange of five species of the genus Rubus co-occurring in the Pacific Northwest of western North America in a greenhouse common garden. Contrary to expectations, nighttime transpiration was not correlated to daytime water use. Nighttime transpiration showed pronounced phylogenetic signals, but the proportion of variation explained by different phylogenetic groupings varied across datasets. Leaf osmotic water potential, water potential at turgor loss point, stomatal size, and specific leaf area were correlated with phylogeny but did not readily explain variation in nighttime transpiration. Patterns in interspecific variation as well as a disconnect between rates of daytime and nighttime transpiration suggest that variation in nighttime water use may be at least partly driven by genetic factors independent of those that control daytime water use. Future work with co-occurring congeneric systems is needed to establish the generality of these results and may help determine the mechanism driving interspecific variation in nighttime water use. PMID:26380686

Flight evaluation of a computer aided low-altitude helicopter flight guidance system

NASA Technical Reports Server (NTRS)

Swenson, Harry N.; Jones, Raymond D.; Clark, Raymond

1993-01-01

The Flight Systems Development branch of the U.S. Army's Avionics Research and Development Activity (AVRADA) and NASA Ames Research Center developed for flight testing a Computer Aided Low-Altitude Helicopter Flight (CALAHF) guidance system. The system includes a trajectory-generation algorithm which uses dynamic programming and a helmet-mounted display (HMD) presentation of a pathway-in-the-sky, a phantom aircraft, and flight-path vector/predictor guidance symbology. The trajectory-generation algorithm uses knowledge of the global mission requirements, a digital terrain map, aircraft performance capabilities, and precision navigation information to determine a trajectory between mission waypoints that seeks valleys to minimize threat exposure. This system was developed and evaluated through extensive use of piloted simulation and has demonstrated a 'pilot centered' concept of automated and integrated navigation and terrain mission planning flight guidance. This system has shown a significant improvement in pilot situational awareness, and mission effectiveness as well as a decrease in training and proficiency time required for a near terrain, nighttime, adverse weather system.

The Atacama Cosmology Telescope: Two-Season ACTPol Spectra and Parameters

NASA Technical Reports Server (NTRS)

Louis, Thibaut; Grace, Emily; Hasselfield, Matthew; Lungu, Marius; Maurin, Loic; Addison, Graeme E.; Adem Peter A. R.; Aiola, Simone; Allison, Rupert; Amiri, Mandana;

The Atacama Cosmology Telescope: two-season ACTPol spectra and parameters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Louis, Thibaut; Grace, Emily; Aiola, Simone

We present the temperature and polarization angular power spectra measured by the Atacama Cosmology Telescope Polarimeter (ACTPol). We analyze night-time data collected during 2013–14 using two detector arrays at 149 GHz, from 548 deg{sup 2} of sky on the celestial equator. We use these spectra, and the spectra measured with the MBAC camera on ACT from 2008–10, in combination with planck and wmap data to estimate cosmological parameters from the temperature, polarization, and temperature-polarization cross-correlations. We find the new ACTPol data to be consistent with the ΛCDM model. The ACTPol temperature-polarization cross-spectrum now provides stronger constraints on multiple parameters thanmore » the ACTPol temperature spectrum, including the baryon density, the acoustic peak angular scale, and the derived Hubble constant. The new ACTPol data provide information on damping tail parameters. The joint uncertainty on the number of neutrino species and the primordial helium fraction is reduced by 20% when adding ACTPol to Planck temperature data alone.« less

The Atacama Cosmology Telescope: two-season ACTPol spectra and parameters

NASA Astrophysics Data System (ADS)

Louis, Thibaut; Grace, Emily; Hasselfield, Matthew; Lungu, Marius; Maurin, Loïc; Addison, Graeme E.; Ade, Peter A. R.; Aiola, Simone; Allison, Rupert; Amiri, Mandana; Angile, Elio; Battaglia, Nicholas; Beall, James A.; de Bernardis, Francesco; Bond, J. Richard; Britton, Joe; Calabrese, Erminia; Cho, Hsiao-mei; Choi, Steve K.; Coughlin, Kevin; Crichton, Devin; Crowley, Kevin; Datta, Rahul; Devlin, Mark J.; Dicker, Simon R.; Dunkley, Joanna; Dünner, Rolando; Ferraro, Simone; Fox, Anna E.; Gallardo, Patricio; Gralla, Megan; Halpern, Mark; Henderson, Shawn; Hill, J. Colin; Hilton, Gene C.; Hilton, Matt; Hincks, Adam D.; Hlozek, Renée; Ho, S. P. Patty; Huang, Zhiqi; Hubmayr, Johannes; Huffenberger, Kevin M.; Hughes, John P.; Infante, Leopoldo; Irwin, Kent; Muya Kasanda, Simon; Klein, Jeff; Koopman, Brian; Kosowsky, Arthur; Li, Dale; Madhavacheril, Mathew; Marriage, Tobias A.; McMahon, Jeff; Menanteau, Felipe; Moodley, Kavilan; Munson, Charles; Naess, Sigurd; Nati, Federico; Newburgh, Laura; Nibarger, John; Niemack, Michael D.; Nolta, Michael R.; Nuñez, Carolina; Page, Lyman A.; Pappas, Christine; Partridge, Bruce; Rojas, Felipe; Schaan, Emmanuel; Schmitt, Benjamin L.; Sehgal, Neelima; Sherwin, Blake D.; Sievers, Jon; Simon, Sara; Spergel, David N.; Staggs, Suzanne T.; Switzer, Eric R.; Thornton, Robert; Trac, Hy; Treu, Jesse; Tucker, Carole; Van Engelen, Alexander; Ward, Jonathan T.; Wollack, Edward J.

2017-06-01

We present the temperature and polarization angular power spectra measured by the Atacama Cosmology Telescope Polarimeter (ACTPol). We analyze night-time data collected during 2013-14 using two detector arrays at 149 GHz, from 548 deg2 of sky on the celestial equator. We use these spectra, and the spectra measured with the MBAC camera on ACT from 2008-10, in combination with planck and wmap data to estimate cosmological parameters from the temperature, polarization, and temperature-polarization cross-correlations. We find the new ACTPol data to be consistent with the ΛCDM model. The ACTPol temperature-polarization cross-spectrum now provides stronger constraints on multiple parameters than the ACTPol temperature spectrum, including the baryon density, the acoustic peak angular scale, and the derived Hubble constant. The new ACTPol data provide information on damping tail parameters. The joint uncertainty on the number of neutrino species and the primordial helium fraction is reduced by 20% when adding ACTPol to Planck temperature data alone.

First Satellite-detected Perturbations of Outgoing Longwave Radiation Associated with Blowing Snow Events over Antarctica

NASA Technical Reports Server (NTRS)

Yang, Yuekui; Palm, Stephen P.; Marshak, Alexander; Wu, Dong L.; Yu, Hongbin; Fu, Qiang

2014-01-01

We present the first satellite-detected perturbations of the outgoing longwave radiation (OLR) associated with blowing snow events over the Antarctic ice sheet using data from Cloud-Aerosol Lidar with Orthogonal Polarization and Clouds and the Earth's Radiant Energy System. Significant cloud-free OLR differences are observed between the clear and blowing snow sky, with the sign andmagnitude depending on season and time of the day. During nighttime, OLRs are usually larger when blowing snow is present; the average difference in OLRs between without and with blowing snow over the East Antarctic Ice Sheet is about 5.2 W/m2 for the winter months of 2009. During daytime, in contrast, the OLR perturbation is usually smaller or even has the opposite sign. The observed seasonal variations and day-night differences in the OLR perturbation are consistent with theoretical calculations of the influence of blowing snow on OLR. Detailed atmospheric profiles are needed to quantify the radiative effect of blowing snow from the satellite observations.

Gravitational starlight deflection measurements during the 21 August 2017 total solar eclipse

NASA Astrophysics Data System (ADS)

Bruns, Donald G.

2018-04-01

Precise star positions near the Sun were measured during the 21 August 2017 total solar eclipse in order to measure their gravitational deflections. The equipment, procedures, and analysis are described in detail. A portable refractor, a CCD camera, and a computerized mount were set up in Wyoming. Detailed calibrations were necessary to improve accuracy and precision. Nighttime measurements taken just before the eclipse provided cubic optical distortion corrections. Calibrations based on star field images 7.4° on both sides of the Sun taken during totality gave linear and quadratic plate constants. A total of 45 images of the sky surrounding the Sun were acquired during the middle part of totality, with an integrated exposure of 22 s. The deflection analysis depended on accurate star positions from the USNO’s UCAC5 star catalog. The final result was a deflection coefficient L  =  1.7512 arcsec, in perfect agreement with the theoretical value, with an uncertainty of only 3%.

Nighttime Fears and Fantasy-Reality Differentiation in Preschool Children

ERIC Educational Resources Information Center

Zisenwine, Tamar; Kaplan, Michal; Kushnir, Jonathan; Sadeh, Avi

2013-01-01

Nighttime fears are very common in preschool years. During these years, children's fantasy-reality differentiation undergoes significant development. Our study was aimed at exploring the links between nighttime fears and fantasy-reality differentiation in preschool children. Eighty children (aged: 4-6 years) suffering from severe nighttime fears…

Black Sea impact on its west-coast land surface temperature

NASA Astrophysics Data System (ADS)

Cheval, Sorin; Constantin, Sorin

2018-03-01

This study investigates the Black Sea influence on the thermal characteristics of its western hinterland based on satellite imagery acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS). The marine impact on the land surface temperature (LST) values is detected at daily, seasonal and annual time scales, and a strong linkage with the land cover is demonstrated. The remote sensing products used within the study supply LST data with complete areal coverage during clear sky conditions at 1-km spatial resolution, which is appropriate for climate studies. The sea influence is significant up to 4-5 km, by daytime, while the nighttime influence is very strong in the first 1-2 km, and it gradually decreases westward. Excepting the winter, the daytime temperature increases towards the plateau with the distance from the sea, e.g. with a gradient of 0.9 °C/km in the first 5 km in spring or with 0.7 °C/km in summer. By nighttime, the sea water usually remains warmer than the contiguous land triggering higher LST values in the immediate proximity of the coastline in all seasons, e.g. mean summer LST is 19.0 °C for the 1-km buffer, 16.6 °C for the 5-km buffer and 16.0 °C for the 10-km buffer. The results confirm a strong relationship between the land cover and thermal regime in the western hinterland of the Black Sea coast. The satellite-derived LST and air temperature values recorded at the meteorological stations are highly correlated for similar locations, but the marine influence propagates differently, pledging for distinct analysis. Identified anomalies in the general observed trends are investigated in correlation with sea surface temperature dynamics in the coastal area.

Fatal accidents in nighttime vs. daytime highway construction work zones.

PubMed

Arditi, David; Lee, Dong-Eun; Polat, Gul

2007-01-01

Awareness about worker safety in nighttime construction has been a major concern because it is believed that nighttime construction creates hazardous work conditions. However, only a few studies provide valuable comparative information about accident characteristics of nighttime and daytime highway construction activities. This study investigates fatal accidents that occurred in Illinois highway work zones in the period 1996-2001 in order to determine the safety differences between nighttime and daytime highway construction. The lighting and weather conditions were included into the study as control parameters to see their effects on the frequency of fatal accidents occurring in work zones. According to this study, there is evidence that nighttime construction is more hazardous than daytime construction. The inclusion of a weather parameter into the analysis has limited effect on this finding. The study justifies establishing an efficient work zone accident reporting system and taking all necessary measures to enhance safety in nighttime work zones.

21 CFR 338.10 - Nighttime sleep-aid active ingredients.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Nighttime sleep-aid active ingredients. 338.10... (CONTINUED) DRUGS FOR HUMAN USE NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 338.10 Nighttime sleep-aid active ingredients. The active ingredient of the product consists of...

21 CFR 338.10 - Nighttime sleep-aid active ingredients.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Nighttime sleep-aid active ingredients. 338.10... (CONTINUED) DRUGS FOR HUMAN USE NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 338.10 Nighttime sleep-aid active ingredients. The active ingredient of the product consists of...

21 CFR 338.10 - Nighttime sleep-aid active ingredients.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Nighttime sleep-aid active ingredients. 338.10... (CONTINUED) DRUGS FOR HUMAN USE NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 338.10 Nighttime sleep-aid active ingredients. The active ingredient of the product consists of...

21 CFR 338.10 - Nighttime sleep-aid active ingredients.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Nighttime sleep-aid active ingredients. 338.10... (CONTINUED) DRUGS FOR HUMAN USE NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 338.10 Nighttime sleep-aid active ingredients. The active ingredient of the product consists of...

21 CFR 338.10 - Nighttime sleep-aid active ingredients.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Nighttime sleep-aid active ingredients. 338.10... (CONTINUED) DRUGS FOR HUMAN USE NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Active Ingredients § 338.10 Nighttime sleep-aid active ingredients. The active ingredient of the product consists of...

Development of a model performance-based sign sheeting specification based on the evaluation of nighttime traffic signs using legibility and eye-tracker data.

DOT National Transportation Integrated Search

2010-09-01

This project focused on the evaluation of traffic sign sheeting performance in terms of meeting the nighttime : driver needs. The goal was to develop a nighttime driver needs specification for traffic signs. The : researchers used nighttime sign legi...

How to model moon signals using 2-dimensional Gaussian function: Classroom activity for measuring nighttime cloud cover

NASA Astrophysics Data System (ADS)

Gacal, G. F. B.; Lagrosas, N.

2016-12-01

Nowadays, cameras are commonly used by students. In this study, we use this instrument to look at moon signals and relate these signals to Gaussian functions. To implement this as a classroom activity, students need computers, computer software to visualize signals, and moon images. A normalized Gaussian function is often used to represent probability density functions of normal distribution. It is described by its mean m and standard deviation s. The smaller standard deviation implies less spread from the mean. For the 2-dimensional Gaussian function, the mean can be described by coordinates (x0, y0), while the standard deviations can be described by sx and sy. In modelling moon signals obtained from sky-cameras, the position of the mean (x0, y0) is solved by locating the coordinates of the maximum signal of the moon. The two standard deviations are the mean square weighted deviation based from the sum of total pixel values of all rows/columns. If visualized in three dimensions, the 2D Gaussian function appears as a 3D bell surface (Fig. 1a). This shape is similar to the pixel value distribution of moon signals as captured by a sky-camera. An example of this is illustrated in Fig 1b taken around 22:20 (local time) of January 31, 2015. The local time is 8 hours ahead of coordinated universal time (UTC). This image is produced by a commercial camera (Canon Powershot A2300) with 1s exposure time, f-stop of f/2.8, and 5mm focal length. One has to chose a camera with high sensitivity when operated at nighttime to effectively detect these signals. Fig. 1b is obtained by converting the red-green-blue (RGB) photo to grayscale values. The grayscale values are then converted to a double data type matrix. The last conversion process is implemented for the purpose of having the same scales for both Gaussian model and pixel distribution of raw signals. Subtraction of the Gaussian model from the raw data produces a moonless image as shown in Fig. 1c. This moonless image can be used for quantifying cloud cover as captured by ordinary cameras (Gacal et al, 2016). Cloud cover can be defined as the ratio of number of pixels whose values exceeds 0.07 and the total number of pixels. In this particular image, cloud cover value is 0.67.

Nighttime intensivist staffing, mortality, and limits on life support: a retrospective cohort study.

PubMed

Kerlin, Meeta Prasad; Harhay, Michael O; Kahn, Jeremy M; Halpern, Scott D

2015-04-01

Evidence regarding nighttime physician staffing of ICUs is suboptimal. We aimed to determine how nighttime physician staffing models influence patient outcomes. We performed a multicenter retrospective cohort study in a multicenter registry of US ICUs. The exposure variable was the ICU's nighttime physician staffing model. The primary outcome was hospital mortality. Secondary outcomes included new limitations on life support, ICU length of stay, hospital length of stay, and duration of mechanical ventilation. Daytime physician staffing was studied as a potential effect modifier. The study included 270,742 patients in 143 ICUs. Compared with nighttime staffing with an attending intensivist, nighttime staffing without an attending intensivist was not associated with hospital mortality (OR, 1.03; 95% CI, 0.92-1.15; P = .65). This relationship was not modified by daytime physician staffing (interaction P = .19). When nighttime staffing was subcategorized, neither attending nonintensivist nor physician trainee staffing was associated with hospital mortality compared with attending intensivist staffing. However, nighttime staffing without any physician was associated with reduced odds of hospital mortality (OR, 0.79; 95% CI, 0.68-0.91; P = .002) and new limitations on life support (OR, 0.83; 95% CI, 0.75-0.93; P = .001). Nighttime staffing was not associated with ICU or hospital length of stay. Nighttime staffing with an attending nonintensivist was associated with a slightly longer duration of mechanical ventilation (hazard ratio, 1.05; 95% CI, 1.02-1.09; P < .001). We found little evidence that nighttime physician staffing models affect patient outcomes. ICUs without physicians at night may exhibit reduced hospital mortality that is possibly attributable to differences in end-of-life care practices.

A Community-Based Study of Sleep and Cognitive Development in Infants and Toddlers.

PubMed

Sun, Wanqi; Li, Shirley Xin; Jiang, Yanrui; Xu, Xiaojuan; Spruyt, Karen; Zhu, Qi; Tseng, Chia-Huei; Jiang, Fan

2018-06-15

To examine the prevalence and correlates of nighttime awakenings and to explore the association between sleep and cognitive development in a community sample of infants and toddlers. A total of 590 healthy infants (aged 2-11 months) and 512 toddlers (aged 12-30 months) from 8 provinces of China were assessed for their sleep and cognitive development. Data on sleep duration and nighttime awakenings were collected through the Brief Infant Sleep Questionnaire. Cognitive development was assessed by trained pediatricians using the Bayley Scales of Infant Development. Prevalence of no nighttime awakening, and nighttime awakening(s) for 1×/night, 2×/night, and ≥ 3×/night was 6.8%, 20.2%, 33.2%, and 39.3% in infants, and was 25.8%, 34.6%, 23.8%, and 15.8% in toddlers, respectively. Nighttime awakenings were generally associated with younger age, lower maternal education level, and being currently breastfed. In addition, nighttime awakenings were associated with being boys in toddlers. After controlling for potential confounders, infants with nighttime awakenings for 2×/night were found to have significantly higher Mental Development Index (MDI) score, as compared to those without and those with more frequent nighttime awakenings. However, toddlers with nighttime awakenings for ≥ 3×/night had significantly lower MDI, as compared to those with fewer nighttime awakenings. Total sleep duration was not associated with any developmental indices in both infants and toddlers. Frequent nighttime awakenings are associated with poor cognitive functions in toddlers. Meanwhile, a nonlinear association between nighttime awakenings and cognitive performance was found among infants. The findings provide a developmental context for the effect of sleep on cognitive abilities in young children. Further longitudinal studies and interventional studies on the effects of parent-based sleep-focused intervention on cognitive abilities among young children are warranted. © 2018 American Academy of Sleep Medicine.

21 CFR 338.50 - Labeling of nighttime sleep-aid drug products.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Labeling of nighttime sleep-aid drug products. 338... SERVICES (CONTINUED) DRUGS FOR HUMAN USE NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Labeling § 338.50 Labeling of nighttime sleep-aid drug products. (a) Statement of identity. The labeling of...

21 CFR 338.50 - Labeling of nighttime sleep-aid drug products.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Labeling of nighttime sleep-aid drug products. 338... SERVICES (CONTINUED) DRUGS FOR HUMAN USE NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Labeling § 338.50 Labeling of nighttime sleep-aid drug products. (a) Statement of identity. The labeling of...

21 CFR 338.50 - Labeling of nighttime sleep-aid drug products.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Labeling of nighttime sleep-aid drug products. 338... SERVICES (CONTINUED) DRUGS FOR HUMAN USE NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Labeling § 338.50 Labeling of nighttime sleep-aid drug products. (a) Statement of identity. The labeling of...

21 CFR 338.50 - Labeling of nighttime sleep-aid drug products.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Labeling of nighttime sleep-aid drug products. 338... SERVICES (CONTINUED) DRUGS FOR HUMAN USE NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Labeling § 338.50 Labeling of nighttime sleep-aid drug products. (a) Statement of identity. The labeling of...

When Thinking Impairs Sleep: Trait, Daytime and Nighttime Repetitive Thinking in Insomnia.

PubMed

Lancee, Jaap; Eisma, Maarten C; van Zanten, Kristopher B; Topper, Maurice

2017-01-01

We performed two studies in individuals with sleep problems to investigate trait, daytime, and nighttime repetitive thinking as risk factors for insomnia. In Study 1, 139 participants completed questionnaires on worry, rumination, insomnia, anxiety, depression, and a sleep diary. Trait rumination and trait worry were not associated with sleep impairment. In Study 2, 64 participants completed similar measures and a daytime and nighttime sleep-related worry diary. Only nighttime sleep-related worry was consistently associated with sleep impairment. Overall, results indicate that nighttime sleep-related worry is important in the maintenance of insomnia, whereas effects of trait and daytime repetitive thinking are more benign. Treatment for insomnia can potentially be improved by focusing more on nighttime sleep-related worry.

Greater nighttime blood pressure variability is associated with left atrial enlargement in atrial fibrillation patients with preserved ejection fraction.

PubMed

Norioka, Naoki; Iwata, Shinichi; Ito, Asahiro; Tamura, Soichiro; Kawai, Yu; Nonin, Shinichi; Ishikawa, Sera; Doi, Atsushi; Hanatani, Akihisa; Yoshiyama, Minoru

2018-06-13

Left atrial enlargement is an independent risk factor for ischemic stroke in patients with atrial fibrillation. Little is known regarding the association between nighttime blood pressure variability and left atrial enlargement in patients with atrial fibrillation and preserved ejection fraction. The study population consisted of 140 consecutive patients with atrial fibrillation (mean age 64 ± 10 years) with preserved ejection fraction (≥50%). Nighttime blood pressure was measured at hourly intervals, using a home blood pressure monitoring device. Nighttime blood pressure variability was expressed as the standard deviation of all readings. Left atrial volume index was measured using the modified Simpson's biplane method with transthoracic echocardiography. Multiple regression analysis indicated that nighttime mean systolic/diastolic blood pressure and its variability remained independently associated with left atrial enlargement after adjustment for age, sex, anti-hypertensive medication class, and left ventricular mass index (P < 0.01). When patients were divided into four groups according to nighttime blood pressure and its variability, the group with higher nighttime blood pressure and its variability had significantly larger left atrial volume than the group with lower nighttime blood pressure and its variability (46.6 ml/m 2 vs. 35.0 ml/m 2 , P < 0.0001). Higher nighttime blood pressure and its variability are associated with left atrial enlargement. The combination of nighttime blood pressure and its variability has additional predictive value for left atrial enlargement. Intensive intervention for these high-risk patients may avoid or delay progression of left atrial enlargement and reduce the risk of stroke.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Naizhuo; Zhou, Yuyu; Samson, Eric L.

The Defense Meteorological Satellite Program’s Operational Linescan System (DMSP-OLS) nighttime lights imagery has proven to be a powerful remote sensing tool to monitor urbanization and assess socioeconomic activities at large scales. However, the existence of incompatible digital number (DN) values and geometric errors severely limit application of nighttime light image data on multi-year quantitative research. In this study we extend and improve previous studies on inter-calibrating nighttime lights image data to obtain more compatible and reliable nighttime lights time series (NLT) image data for China and the United States (US) through four steps: inter-calibration, geometric correction, steady increase adjustment, andmore » population data correction. We then use gross domestic product (GDP) data to test the processed NLT image data indirectly and find that sum light (summed DN value of pixels in a nighttime light image) maintains apparent increase trends with relatively large GDP growth rates but does not increase or decrease with relatively small GDP growth rates. As nighttime light is a sensitive indicator for economic activity, the temporally consistent trends between sum light and GDP growth rate imply that brightness of nighttime lights on the ground is correctly represented by the processed NLT image data. Finally, through analyzing the corrected NLT image data from 1992 to 2008, we find that China experienced apparent nighttime lights development in 1992-1997 and 2001-2008 respectively and the US suffered from nighttime lights decay in large areas after 2001.« less

Culm Age and Rhizome Affects Night-Time Water Recharge in the Bamboo Phyllostachys pubescens

PubMed Central

Zhao, Xiuhua; Zhao, Ping; Zhang, Zhenzhen; Zhu, Liwei; Hu, Yanting; Ouyang, Lei; Ni, Guangyan; Ye, Qing

2017-01-01

Bamboo species—the only herbaceous trees—have unique structural and physiological characteristics that differ from those of other tree taxa. However, the role of night-time water use in bamboo is poorly understood and has rarely been investigated. We studied the day- and night-time sap flow response to culm age and rhizome structure in three age levels (juvenile, mature, and senescent) of Phyllostachys pubescens growing in the Nankun Mountain Natural Reserve, South China. We found that sap flow density and whole-tree hydraulic conductance decreased with culm age. After cutting of rhizome, the day-time sap flow and night-time water recharge decreased obviously. In addition, night-time water recharge accounted for the largest proportion (up to 30%) of total daily transpiration in normal senescent bamboos. Therefore, our study indicates that the connected rhizome system and night-time water recharge played a significant role in water compensation during the day and at night in bamboos. Night-time water recharge is especially critical to senescent bamboos, given their weaker transpiration due to the lower whole-tree hydraulic conductance, and consequently, they are more dependent on night-time water recharge for fulfilling their whole-day water consumption needs. PMID:29176989

Culm Age and Rhizome Affects Night-Time Water Recharge in the Bamboo Phyllostachys pubescens.

PubMed

Zhao, Xiuhua; Zhao, Ping; Zhang, Zhenzhen; Zhu, Liwei; Hu, Yanting; Ouyang, Lei; Ni, Guangyan; Ye, Qing

2017-01-01

Bamboo species-the only herbaceous trees-have unique structural and physiological characteristics that differ from those of other tree taxa. However, the role of night-time water use in bamboo is poorly understood and has rarely been investigated. We studied the day- and night-time sap flow response to culm age and rhizome structure in three age levels (juvenile, mature, and senescent) of Phyllostachys pubescens growing in the Nankun Mountain Natural Reserve, South China. We found that sap flow density and whole-tree hydraulic conductance decreased with culm age. After cutting of rhizome, the day-time sap flow and night-time water recharge decreased obviously. In addition, night-time water recharge accounted for the largest proportion (up to 30%) of total daily transpiration in normal senescent bamboos. Therefore, our study indicates that the connected rhizome system and night-time water recharge played a significant role in water compensation during the day and at night in bamboos. Night-time water recharge is especially critical to senescent bamboos, given their weaker transpiration due to the lower whole-tree hydraulic conductance, and consequently, they are more dependent on night-time water recharge for fulfilling their whole-day water consumption needs.

Nighttime highway construction illumination.

DOT National Transportation Integrated Search

2014-08-01

The nighttime driving environment, consisting of roadway illumination, signs, vehicle lighting and markers, delineators : and flashing lights, can be complex or even confusing for both pedestrians and drivers. The nighttime construction : environment...

Effects of Nighttime Light Radiance on the Sleep of the General Population

NASA Technical Reports Server (NTRS)

Ohayon, Maurice M.; Milesi, Cristina

2015-01-01

The objectives of this study is to verify if the exposure to greater nighttime radiance is associated with changes in the sleep/wake schedule and with greater sleep disturbances. Methods: The target population was the adults (18 years and older) living in California, USA. This represents 24 million of inhabitants. A total of 3,104 subjects participated in the survey (participation rate 85.6%). The participants were interviewed by telephone using the Sleep-EVAL system. The interviews covered several topics including sleeping habits, sleep quality, sleep disturbances, physical symptoms related to menopause. Chronic insomnia was defined as difficulty initiating or maintaining sleep for at least 3 months. Global nighttime light emissions have been collected by the Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS) sensors. We extracted the radiance calibrated nighttime lights corresponding to the date of the interviews for a three by three window centered on each coordinate corresponding to an interview address. Results: Dissatisfaction with sleep quantity and/or quality was associated with an increased nighttime radiance (p=0.02). Similarly, excessive sleepiness accompanied with impaired functioning was significantly associated with an increased nighttime radiance (p (is) less than 0.0001). The association remained significant after controlling for age, gender and use of a night lamp in the bedroom. Confusional arousals were also significantly associated with an increased nighttime radiance (p (is) less than 0.0001). Bedtime hour was linearly increasing with the intensity of nighttime radiance: the later the bedtime, the greater the nighttime radiance (p (is) less than 0.0001). Similarly, wakeup time became progressively later as the nighttime radiance increased (p (is) less than 0.0001). Both associations remained significant after controlling for age, gender and use of a night lamp in the bedroom. Circadian Rhythm Disorders were the only sleep disorder significantly associated with increased nighttime radiance (p (is) less than 0.0001). Exposure to increased nighttime light radiance appeared to cause a shift in the sleep/wake schedule, excessive sleepiness and Circadian Rhythm Disorders.

Differences in pulmonary biochemical and inflammatory responses of rats and guinea pigs resulting from daytime or nighttime, single and repeated exposure to ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Bree, L.; Marra, M.; Rombout, P.J.

1992-10-01

Rats and guinea pigs were exposed to 0.8 mg ozone (O3)/m3 (approximately 0.4 ppm) for 12 hr during the daytime, 12 hr during the nighttime, or continuously to investigate circadian variation in O3-induced pulmonary toxicity during single and repeated O3 exposures. Biomarkers in bronchoalveolar lavage (BAL) fluid and lung tissues were measured as indicators of biochemical and inflammatory responses. Nighttime O3 exposure of rats resulted in larger increases of protein, albumin, and inflammatory cells in BAL fluid compared to those after daytime O3 exposure and this daytime-nighttime difference was statistically significant (p < 0.05). Single daytime or nighttime O3 exposuremore » of guinea pigs resulted in comparable increases of BAL fluid proteins and inflammatory cells without a daytime-nighttime difference. Nighttime and continuous O3 exposure of rats for 3 days resulted in comparable increases in lung antioxidant enzyme activities, both of which differed statistically from effects from daytime O3 exposures (p < 0.05). Continuous O3 exposure of guinea pigs for 3 days caused, in general, statistically larger increases in lung tissue parameters compared to nighttime O3 exposures (p < 0.05). These results suggest that the extent of O3-induced acute pulmonary biochemical and inflammatory responses is directly related to the level of physical and respiratory activity. For rats, effects from continuous O3 exposure appear to be controlled by the nighttime, physically active period. In guinea pigs, the comparable responses following daytime or nighttime O3 exposure seem in accordance with their random behavioral daily activity pattern. This study supports the view that physical activity-related increases in inhaled dose significantly enhance the pulmonary O3 responses.« less

Daily light integral and day light quality: Potentials and pitfalls of nighttime UV treatments on cucumber powdery mildew.

PubMed

Suthaparan, Aruppillai; Solhaug, Knut Asbjørn; Stensvand, Arne; Gislerød, Hans Ragnar

2017-10-01

Nighttime ultraviolet (UV) radiation, if applied properly, has a significant potential for management of powdery mildews in many crop species. In this study, the role of growth light duration, irradiance, a combination of both (daily light integral) and light spectral quality (blue or red) on the efficacy of UV treatments against powdery mildew caused by Podosphaera xanthii and the growth performance of cucumber plants was studied in growth chambers. Increasing daily light integral provided by high-pressure sodium lamps (HPS) decreased efficacy of nighttime UV treatments against P. xanthii, but it increased plant growth. Furthermore, the efficacy of nighttime UV decreased when day length was increased from 16 to 20h at a constant daily light integral. The efficacy of nighttime UV increased if red light was applied after UV treatment, showing the possibility of day length extension without reducing the effect of UV. Increasing the dose of blue light during daytime reduced the efficacy of nighttime UV in controlling the disease, whereas blue deficient growth light (<6% of blue) caused UV mediated curling of young leaves. Furthermore, application of blue light after nighttime UV reduced its disease control efficacy. This showed the importance of maintaining a minimum of blue light in the growth light before nighttime UV treatment. Findings from this study showed that optimization of nighttime UV for management of powdery mildew is dependent on the spectral composition of the photosynthetically active radiation. Copyright © 2017 Elsevier B.V. All rights reserved.

Nighttime warming enhances drought resistance of plant communities in a temperate steppe

NASA Astrophysics Data System (ADS)

Yang, Zhongling; Jiang, Lin; Su, Fanglong; Zhang, Qian; Xia, Jianyang; Wan, Shiqiang

2016-03-01

Drought events could have profound influence on plant community structure and ecosystem function, and have subsequent impacts on community stability, but we know little about how different climate warming scenarios affect community resistance and resilience to drought. Combining a daytime and nighttime warming experiment in the temperate steppe of north China with a natural drought event during the study period, we tested how daytime and nighttime warming influences drought resistance and resilience. Our results showed that the semi-arid steppe in north China was resistant to both daytime and nighttime warming, but vulnerable to drought. Nighttime warming, but not daytime warming, enhanced community resistance to drought via stimulating carbon sequestration, whereas neither daytime nor nighttime warming affected community resilience to drought. Large decline in plant community cover, primarily caused by the reduction in the cover of dominant and rare species rather than subordinate species during drought, did not preclude rapid ecosystem recovery. These findings suggest that nighttime warming may facilitate ecosystem sustainability and highlight the need to assess the effects of climate extremes on ecosystem functions at finer temporal resolutions than based on diurnal mean temperature.

An evaluation of study design for estimating a time-of-day noise weighting

NASA Technical Reports Server (NTRS)

Fields, J. M.

1986-01-01

The relative importance of daytime and nighttime noise of the same noise level is represented by a time-of-day weight in noise annoyance models. The high correlations between daytime and nighttime noise were regarded as a major reason that previous social surveys of noise annoyance could not accurately estimate the value of the time-of-day weight. Study designs which would reduce the correlation between daytime and nighttime noise are described. It is concluded that designs based on short term variations in nighttime noise levels would not be able to provide valid measures of response to nighttime noise. The accuracy of the estimate of the time-of-day weight is predicted for designs which are based on long term variations in nighttime noise levels. For these designs it is predicted that it is not possible to form satisfactorily precise estimates of the time-of-day weighting.

Nighttime Medium-Scale Traveling Ionospheric Disturbances From Airglow Imager and Global Navigation Satellite Systems Observations

NASA Astrophysics Data System (ADS)

Huang, Fuqing; Lei, Jiuhou; Dou, Xiankang; Luan, Xiaoli; Zhong, Jiahao

2018-01-01

In this study, coordinated airglow imager, GPS total electron content (TEC), and Beidou geostationary orbit (GEO) TEC observations for the first time are used to investigate the characteristics of nighttime medium-scale traveling ionospheric disturbances (MSTIDs) over central China. The results indicated that the features of nighttime MSTIDs from three types of observations are generally consistent, whereas the nighttime MSTID features from the Beidou GEO TEC are in better agreement with those from airglow images as compared with the GPS TEC, given that the nighttime MSTID characteristics from GPS TEC are significantly affected by Doppler effect due to satellite movement. It is also found that there are three peaks in the seasonal variations of the occurrence rate of nighttime MSTIDs in 2016. Our study revealed that the Beidou GEO satellites provided fidelity TEC observations to study the ionospheric variability.

Analysis of post-earthquake reconstruction for Wenchuan earthquake based on night-time light data from DMSP/OLS

NASA Astrophysics Data System (ADS)

Cao, Yang; Zhang, Jing; Yang, Mingxiang; Lei, Xiaohui

2017-07-01

At present, most of Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS) night-time light data are applied to large-scale regional development assessment, while there are little for the study of earthquake and other disasters. This study has extracted night-time light information before and after earthquake within Wenchuan county with adoption of DMSP/OLS night-time light data. The analysis results show that the night-time light index and average intensity of Wenchuan county were decreased by about 76% and 50% respectively from the year of 2007 to 2008. From the year of 2008 to 2011, the two indicators were increased by about 200% and 556% respectively. These research results show that the night-time light data can be used to extract the information of earthquake and evaluate the occurrence of earthquakes and other disasters.

Three times greater weight of daytime than of night-time temperature on leaf unfolding phenology in temperate trees.

PubMed

Fu, Yongshuo H; Liu, Yongjie; De Boeck, Hans J; Menzel, Annette; Nijs, Ivan; Peaucelle, Marc; Peñuelas, Josep; Piao, Shilong; Janssens, Ivan A

2016-11-01

The phenology of spring leaf unfolding plays a key role in the structure and functioning of ecosystems. The classical concept of heat requirement (growing degree days) for leaf unfolding was developed hundreds of years ago, but this model does not include the recently reported greater importance of daytime than night-time temperature. A manipulative experiment on daytime vs night-time warming with saplings of three species of temperate deciduous trees was conducted and a Bayesian method was applied to explore the different effects of daytime and night-time temperatures on spring phenology. We found that both daytime and night-time warming significantly advanced leaf unfolding, but the sensitivities to increased daytime and night-time temperatures differed significantly. Trees were most sensitive to daytime warming (7.4 ± 0.9, 4.8 ± 0.3 and 4.8 ± 0.2 d advancement per degree Celsius warming (d °C -1 ) for birch, oak and beech, respectively) and least sensitive to night-time warming (5.5 ± 0.9, 3.3 ± 0.3 and 2.1 ± 0.9 d °C -1 ). Interestingly, a Bayesian analysis found that the impact of daytime temperature on leaf unfolding was approximately three times higher than that of night-time temperatures. Night-time global temperature is increasing faster than daytime temperature, so model projections of future spring phenology should incorporate the effects of these different temperatures. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Effects of NOx control and plume mixing on nighttime chemical processing of plumes from coal-fired power plants

NASA Astrophysics Data System (ADS)

Brown, Steven S.; Dubé, William P.; Karamchandani, Prakash; Yarwood, Greg; Peischl, Jeff; Ryerson, Thomas B.; Neuman, J. Andrew; Nowak, John B.; Holloway, John S.; Washenfelder, Rebecca A.; Brock, Charles A.; Frost, Gregory J.; Trainer, Michael; Parrish, David D.; Fehsenfeld, Frederick C.; Ravishankara, A. R.

2012-04-01

Coal-fired electric power plants produce a large fraction of total U.S. NOx emissions, but NOx from this sector has been declining in the last decade owing to installation of control technology. Nighttime aircraft intercepts of plumes from two different Texas power plants (Oklaunion near Wichita Falls and W. A. Parish near Houston) with different control technologies demonstrate the effect of these reductions on nighttime NOxoxidation rates. The analysis shows that the spatial extent of nighttime-emitted plumes to be quite limited and that mixing of highly concentrated plume NOx with ambient ozone is a determining factor for its nighttime oxidation. The plume from the uncontrolled plant had full titration of ozone through 74 km/2.4 h of downwind transport that suppressed nighttime oxidation of NO2 to higher oxides of nitrogen across the majority of the plume. The plume from the controlled plant did not have sufficient NOx to titrate background ozone, which led to rapid nighttime oxidation of NO2 during downwind transport. A plume model that includes horizontal mixing and nighttime chemistry reproduces the observed structures of the nitrogen species in the plumes from the two plants. The model shows that NOx controls not only reduce the emissions directly but also lead to an additional overnight NOx loss of 36-44% on average. The maximum reduction for 12 h of transport in darkness was 73%. The results imply that power plant NOxemissions controls may produce a larger than linear reduction in next-day, downwind ozone production following nighttime transport.

Lessons from simultaneous measurements of soil respiration and net ecosystem exchange of CO2 in temperate forests

NASA Astrophysics Data System (ADS)

Renchon, A.; Pendall, E.

2017-12-01

Land-surface exchanges of CO2 play a key role in ameliorating or exacerbating climate change. The eddy-covariance method allows direct measurement of net ecosystem-atmosphere exchange of CO2 (NEE), but partitioning daytime NEE into its components - gross primary productivity (GPP) and ecosystem respiration (RE) - remains challenging. Continuous measurements of soil respiration (RS), along with flux towers, have the potential to better constrain data and models of RE and GPP. We use simultaneous half-hourly NEE and RS data to: (1) compare the short-term (fortnightly) apparent temperature sensitivity (Q10) of nighttime RS and RE; (2) assess whether daytime RS can be estimated using nighttime response functions; and (3) compare the long-term (annual) responses of nighttime RS and nighttime RE to interacting soil moisture and soil temperature. We found that nighttime RS has a lower short-term Q10 than nighttime RE. This suggests that the Q10 of nighttime RE is strongly influenced by the Q10 of nighttime above-ground respiration, or possibly by a bias in RE measurements. The short-term Q10 of RS and RE decreased with increasing temperature. In general, daytime RS could be estimated using nighttime RS temperature and soil moisture (r2 = 0.9). However, this results from little to no diurnal variation in RS, and estimating daytime RS as the average of nighttime RS gave similar results (r2 = 0.9). Furthermore, we observed a day-night hysteresis of RS response to temperature, especially when using air temperature and sometimes when using soil temperature at 5cm depth. In fact, during some months, soil respiration observations were lower during daytime compared to nighttime, despite higher temperature in daytime. Therefore, daytime RS modelled from nighttime RS temperature response was overestimated during these periods. RS and RE responses to the combination of soil moisture and soil temperature were similar, and consistent with the DAMM model of soil-C decomposition. These findings underscore the value of continuous measurements of RS in flux tower footprints. Findings are also relevant to recent research on light inhibition of leaf respiration and contribute to improved understanding of ecosystem carbon cycle - climate feedback processes.

Effect on asphalt quality due to nighttime construction : final report.

DOT National Transportation Integrated Search

2017-06-01

The objectives of this project were to identify and analyze the nighttime paving traffic control standards in other states and compare the effects of daytime vs. nighttime paving on quality, safety, costs, and construction time. Surveys of various De...

A study of nighttime seat belt use in Indiana

DOT National Transportation Integrated Search

2007-05-01

Overall belt use rates observed during the daytime and nighttime survey waves are presented in Table 2. Belt use observed during the daytime and nighttime pre-mobilization waves was very similar. During the post-mobilization waves, daytime belt use w...

Application of Satellite and Ozonesonde Data to the Study of Nighttime Tropospheric Ozone Impacts and Relationship to Air Quality

NASA Astrophysics Data System (ADS)

Osterman, G. B.; Eldering, A.; Neu, J. L.; Tang, Y.; McQueen, J.; Pinder, R. W.

2011-12-01

To help protect human health and ecosystems, regional-scale atmospheric chemistry models are used to forecast high ozone events and to design emission control strategies to decrease the frequency and severity of ozone events. Despite the impact that nighttime aloft ozone can have on surface ozone, regional-scale atmospheric chemistry models often do not simulate the nighttime ozone concentrations well and nor do they sufficiently capture the ozone transport patterns. Fully characterizing the importance of the nighttime ozone has been hampered by limited measurements of the vertical distribution of ozone and ozone-precursors. The main focus of this work is to begin to utilize remote sensing data sets to characterize the impact of nighttime aloft ozone to air quality events. We will describe our plans to use NASA satellite data sets, transport models and air quality models to study ozone transport, focusing primarily on nighttime ozone and provide initial results. We will use satellite and ozonesonde data to help understand how well the air quality models are simulating ozone in the lower free troposphere and attempt to characterize the impact of nighttime ozone to air quality events. Our specific objectives are: 1) Characterize nighttime aloft ozone using remote sensing data and sondes. 2) Evaluate the ability of the Community Multi-scale Air Quality (CMAQ) model and the National Air Quality Forecast Capability (NAQFC) model to capture the nighttime aloft ozone and its relationship to air quality events. 3) Analyze a set of air quality events and determine the relationship of air quality events to the nighttime aloft ozone. We will achieve our objectives by utilizing the ozone profile data from the NASA Earth Observing System (EOS) Tropospheric Emission Spectrometer (TES) and other sensors, ozonesonde data collected during the Aura mission (IONS), EPA AirNow ground station ozone data, the CMAQ continental-scale air quality model, and the National Air Quality Forecast model.

Example MODIS Global Cloud Optical and Microphysical Properties: Comparisons between Terra and Aqua

NASA Technical Reports Server (NTRS)

Hubanks, P. A.; Platnick, S.; King, M. D.; Ackerman, S. A.; Frey, R. A.

2003-01-01

MODIS observations from the NASA EOS Terra spacecraft (launched in December 1999, 1030 local time equatorial crossing) have provided a unique data set of Earth observations. With the launch of the NASA Aqua spacecraft in May 2002 (1330 local time), two MODIS daytime (sunlit) and nighttime observations are now available in a 24 hour period, allowing for some measure of diurnal variability. We report on an initial analysis of several operational global (Level-3) cloud products from the two platforms. The MODIS atmosphere Level-3 products, which include clear-sky and aerosol products in addition to cloud products, are available as three separate files providing daily, eight-day, and monthly aggregations; each temporal aggregation is spatially aggregated to a 1 degree grid. The files contain approximately 600 statisitical datasets (from simple means and standard deviations to 1 - and 2-dimensional histograms). Operational cloud products include detection (cloud fraction), cloud-top properties, and daytimeonly cloud optical thickness and particle effective radius for both water and ice clouds. We will compare example global Terra and Aqua cloud fraction, optical thickness, and effective radius aggregations.

UV Lidar Receiver Analysis for Tropospheric Sensing of Ozone

NASA Technical Reports Server (NTRS)

Pliutau, Denis; DeYoung, Russell J.

2013-01-01

A simulation of a ground based Ultra-Violet Differential Absorption Lidar (UV-DIAL) receiver system was performed under realistic daytime conditions to understand how range and lidar performance can be improved for a given UV pulse laser energy. Calculations were also performed for an aerosol channel transmitting at 3 W. The lidar receiver simulation studies were optimized for the purpose of tropospheric ozone measurements. The transmitted lidar UV measurements were from 285 to 295 nm and the aerosol channel was 527-nm. The calculations are based on atmospheric transmission given by the HITRAN database and the Modern Era Retrospective Analysis for Research and Applications (MERRA) meteorological data. The aerosol attenuation is estimated using both the BACKSCAT 4.0 code as well as data collected during the CALIPSO mission. The lidar performance is estimated for both diffuseirradiance free cases corresponding to nighttime operation as well as the daytime diffuse scattered radiation component based on previously reported experimental data. This analysis presets calculations of the UV-DIAL receiver ozone and aerosol measurement range as a function of sky irradiance, filter bandwidth and laser transmitted UV and 527-nm energy

Division G Commission 21: Galactic and Extragalactic Backgrounds Radiation

NASA Astrophysics Data System (ADS)

Murthy, Jayant; Witt, Adolf; Baggaley, W. Jack; Dwek, Eli; Levasseur-Regourd, Anny-Chantal; Mann, Ingrid; Mattila, Kalevi; Watanabe, Jun-Ichi

2016-04-01

Commission 21 was one of the oldest and smallest in the IAU yet one which underwent the most evolution since its inception. It began in 1955 as Light of the Night Sky (Lumière du Ciel Nocturne) under the Presidentship of Jean Dufay (University Observatory at Lyon). As the name suggested, in the years before space observations, its focus was on observations of atmospheric light which, at the time, was the domain of astronomers. Thus the early proceedings of the Commission were dominated by reports of the daytime and nighttime emission as observed from different locations and different conditions. Our knowledge of the Earth's atmosphere is still shaped by these early observations (Meier R.R., 1991, Space Sci. Rev. 58, 1). Members of Commission 21 were key to organizing interational collaborations to set up atmospheric stations at different latitudes, including in the Souther hemisphere and in ensuring a consistent calibration between the instruments. The Commission also bought in results from Soviet scientists in an era where communication was limited by both politics and language.

A National Evaluation of the Nighttime and Passenger Restriction Components of Graduated Driver Licensing

PubMed Central

Fell, James C.; Todd, Michael; Voas, Robert B.

2011-01-01

Introduction The high crash rate of youthful novice drivers has been recognized for half a century. Over the last decade, graduated driver licensing (GDL) systems, which extend the period of supervised driving and limit the novice’s exposure to higher-risk conditions (such as nighttime driving) has effectively reduced crash involvements of novice drivers. Method This study used data from the Fatality Analysis Reporting System (FARS) and the implementation dates of GDL laws in a state-by-year panel study to evaluate the effectiveness of two key elements of GDL laws: nighttime restrictions and passenger limitations. Results Nighttime restrictions were found to reduce 16- and 17-year-old driver involvements in nighttime fatal crashes by an estimated 10% and 16- and 17-year-old drinking drivers in nighttime fatal crashes by 13%. Passenger restrictions were found to reduce 16- and 17-year-old driver involvements in fatal crashes with teen passengers by an estimated 9%. Conclusions These results confirm the effectiveness of these provisions in GDL systems. Impact on Public Health The results of this study indicate that nighttime restrictions and passenger limitations are very important components of any GDL law. PMID:22017831

Nighttime warming enhances drought resistance of plant communities in a temperate steppe

PubMed Central

Yang, Zhongling; Jiang, Lin; Su, Fanglong; Zhang, Qian; Xia, Jianyang; Wan, Shiqiang

2016-01-01

Drought events could have profound influence on plant community structure and ecosystem function, and have subsequent impacts on community stability, but we know little about how different climate warming scenarios affect community resistance and resilience to drought. Combining a daytime and nighttime warming experiment in the temperate steppe of north China with a natural drought event during the study period, we tested how daytime and nighttime warming influences drought resistance and resilience. Our results showed that the semi-arid steppe in north China was resistant to both daytime and nighttime warming, but vulnerable to drought. Nighttime warming, but not daytime warming, enhanced community resistance to drought via stimulating carbon sequestration, whereas neither daytime nor nighttime warming affected community resilience to drought. Large decline in plant community cover, primarily caused by the reduction in the cover of dominant and rare species rather than subordinate species during drought, did not preclude rapid ecosystem recovery. These findings suggest that nighttime warming may facilitate ecosystem sustainability and highlight the need to assess the effects of climate extremes on ecosystem functions at finer temporal resolutions than based on diurnal mean temperature. PMID:26987482

A study of nighttime seat belt use in Indiana

DOT National Transportation Integrated Search

2006-09-01

A direct observation study of nighttime seat belt use was conducted in Indiana surrounding the Click It or Ticket (May Mobilization) activities. Two nighttime full statewide surveys were conducted, one in April and the other in June 2006. For this st...

Long-term assessment of the CALIPSO Imaging Infrared Radiometer (IIR) calibration and stability through simulated and observed comparisons with MODIS/Aqua and SEVIRI/Meteosat

NASA Astrophysics Data System (ADS)

Garnier, Anne; Scott, Noëlle A.; Pelon, Jacques; Armante, Raymond; Crépeau, Laurent; Six, Bruno; Pascal, Nicolas

2017-04-01

The quality of the calibrated radiances of the medium-resolution Imaging Infrared Radiometer (IIR) on-board the CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) satellite is quantitatively evaluated from the beginning of the mission in June 2006. Two complementary relative and stand-alone approaches are used, which are related to comparisons of measured brightness temperatures and to model-to-observations comparisons, respectively. In both cases, IIR channels 1 (8.65 µm), 2 (10.6 µm), and 3 (12.05 µm) are paired with the Moderate Resolution Imaging Spectroradiometer (MODIS)/Aqua Collection 5 companion channels 29, 31, and 32, respectively, as well as with the Spinning Enhanced Visible and Infrared Imager (SEVIRI)/Meteosat companion channels IR8.7, IR10.8, and IR12, respectively. These pairs were selected before launch to meet radiometric, geometric, and space-time constraints. The prelaunch studies were based on simulations and sensitivity studies using the 4A/OP radiative transfer model and the more than 2300 atmospheres of the climatological Thermodynamic Initial Guess Retrieval (TIGR) input dataset further sorted into five air mass types. Using data from over 9.5 years of on-orbit operation, and following the relative approach technique, collocated measurements of IIR and of its companion channels have been compared at all latitudes over ocean, during day and night, and for all types of scenes in a wide range of brightness temperatures. The relative approach shows an excellent stability of IIR2-MODIS31 and IIR3-MODIS32 brightness temperature differences (BTDs) since launch. A slight trend within the IIR1-MODIS29 BTD, that equals -0.02 K yr-1 on average over 9.5 years, is detected when using the relative approach at all latitudes and all scene temperatures. For very cold scene temperatures (190-200 K) in the tropics, each IIR channel is warmer than its MODIS companion channel by 1.6 K on average. For the stand-alone approach, clear sky measurements only are considered, which are directly compared with simulations using 4A/OP and collocated ERA-Interim (ERA-I) reanalyses. The clear sky mask is derived from collocated observations from IIR and the CALIPSO lidar. Simulations for clear sky pixels in the tropics reproduce the differences between IIR1 and MODIS29 within 0.02 K and between IIR2 and MODIS31 within 0.04 K, whereas IIR3-MODIS32 is larger than simulated by 0.26 K. The stand-alone approach indicates that the trend identified from the relative approach originates from MODIS29, whereas no trend (less than ±0.004 K yr-1) is identified for any of the IIR channels. Finally, using the relative approach, a year-by-year seasonal bias between nighttime and daytime IIR-MODIS BTD was found at mid-latitude in the Northern Hemisphere. It is due to a nighttime IIR bias as determined by the stand-alone approach, which originates from a calibration drift during day-to-night transitions. The largest bias is in June and July when IIR2 and IIR3 are warmer by 0.4 K on average, and IIR1 is warmer by 0.2 K.

Measurement of Light Pollution of Iranian National Observatory

NASA Astrophysics Data System (ADS)

Son Hosseini, S.; Nasiri, S.

2006-08-01

The problem of Light pollution became important mainly since 1960, by growth of urban development and using more artificial lights and lamps at the nighttimes. Optical telescopes share the same range of wavelengths as are used to provide illumination of roadways, buildings and automobiles. The light glow that emanates from man made pollution will scatter off the atmosphere and affects the images taken by the observatory instruments. A method of estimating the night sky brightness produced by a city of known population and distance is useful in site testing of the new observatories, as well as in studying the likely future deterioration of existing sites. Now with planning the Iranian National Observatory that will house a 2-meter telescope and on the way of the site selection project, studying the light pollution is propounded in Iran. Thus, we need a site with the least light pollution, beside other parameters, i.e. seeing, meteorological, geophysical and local parameters. The seeing parameter is being measured in our 4 preliminary selected sites at Qom, Kashan, Kerman and Birjand since 2 years ago using an out of focus Differential Image Motion Monitor. These sites are selected among 33 candidate sites by studying the meteorological data obtained from the local synoptic stations and the Meteosat. We use the Walker's law to estimate the Sky glow of these sites having the population and the distances of the nearby regions. The results are corrected by the methods introduced by Treanor and Berry using the atmospheric extinction coefficients. The data obtained using an 11 inch telescope with a ST7 CCD camera for above sites are consistent with the estimated values of the light pollution mentioned above.

Inversion of AMSR-E observations for land surface temperature estimation: 2. Global comparison with infrared satellite temperature

NASA Astrophysics Data System (ADS)

Ermida, S. L.; Jiménez, C.; Prigent, C.; Trigo, I. F.; DaCamara, C. C.

2017-03-01

A comparison of land surface temperature (Ts) derived from the Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) with infrared Ts is presented. The infrared Ts include clear-sky estimates from the Moderate Resolution Imaging Spectroradiometer (MODIS), the Spinning Enhanced Visible and Infrared Imager, the Geostationary Operational Environmental Satellite (GOES) Imager, and the Japanese Meteorological Imager. The higher discrepancies between AMSR-E and MODIS are observed over deserts and snow-covered areas. The former seems to be associated with Ts underestimation by MODIS, whereas the latter is mostly related to uncertainties in microwave emissivity over snow/ice. Ts differences between AMSR-E and MODIS are significantly reduced after masking out snow and deserts, with a bias change from 2.6/4.6 K to 3.0/1.4 K for daytime/nighttime and a standard deviation (STD) decrease from 7.3/7.9 K to 5.1/3.9 K. When comparing with all infrared sensors, the STD of the differences between microwave and infrared Ts is generally higher than between IR retrievals. However, the biases between microwave and infrared Ts are, in some cases, of the same order as the ones observed between infrared products. This is the case for GOES, with daytime biases with respect to AMSR-E and MODIS of 0.45 K and 0.60 K, respectively. While the infrared Ts are clear-sky estimates, AMSR-E also provides Ts under cloudy conditions. For frequently cloudy regions, this results in a large increase of available Ts estimates (>250%), making the microwave Ts a very powerful complement of the infrared estimates.

Green or blue spaces? Assessment of the effectiveness and costs to mitigate the urban heat island in a Latin American city

NASA Astrophysics Data System (ADS)

Targino, Admir Créso; Coraiola, Guilherme Conor; Krecl, Patricia

2018-06-01

We measured air temperature at 14 sites with different land cover composition within the urban canopy layer of a mid-sized Brazilian city. The intensity (ΔT) of the urban heat island (UHI) was calculated using data collected above a lake and at an urban park as references. We investigated the spatio-temporal variability of ΔT during four contiguous days with varying weather. The first day was overcast and rainy, giving rise to a moderate UHI. The second day was sunny, which caused the diurnal ΔT fields to become heterogeneous, due to larger heating rates at sites with more man-made surfaces compared to natural surfaces. A high-pressure system observed on the last days brought cloudless skies, causing smaller ΔT during the day and greater at night. We hypothesise that the effect was due to the reduction of cooling via evapotranspiration caused by closing of the stomata as the soil dried out, which reduced the daytime temperature differences among the sites. The night-time effect was caused by stronger radiative cooling due to clear skies. The temperature within the park was always lower than over the lake, confirming that urban forestry is a more effective mechanism to combat the UHI. Introducing a park would be about sevenfold cheaper than building a city pond. Hence, green spaces are not only more efficient to combat the UHI but it is also a cheaper strategy compared to blue spaces. Moreover, vegetation delivers other benefits, such as removal of air pollutants, attenuation of urban noise, improvement of city aesthetic and their use as recreational spaces.

Year 1 of the Washington nighttime seat belt enforcement program : traffic tech.

DOT National Transportation Integrated Search

2010-09-01

The first year of the Washington nighttime belt program : ran from May 2007 through May 2008. During this period, WTSC ran three, two-week nighttime seat belt enforcement : campaigns. The primary message of the ad was that extra : seat-belt-focuse...

Improving the effectiveness of nighttime temporary traffic control warning devices, volume 2 : evaluation of nighttime mobile warning lights.

DOT National Transportation Integrated Search

2013-11-01

Vehicle-mounted warning lights for nighttime mobile highway operations provide critical protection to workers and the driving : public. Alerting the traveling public of the approaching work activity and providing guidance is vital to maintaining safe...

Reducing Dangerous Nighttime Events in Persons with Dementia Using a Nighttime Monitoring System

PubMed Central

Rowe, Meredeth A.; Kelly, Annette; Horne, Claydell; Lane, Steve; Campbell, Judy; Lehman, Brandy; Phipps, Chad; Keller, Meredith; Benito, Andrea Pe

2009-01-01

Background Nighttime activity, a common occurrence in persons with dementia, increases the risk for injury and unattended home exits, and impairs the sleep patterns of caregivers. Technology is needed that will alert caregivers of nighttime activity in persons with dementia to help prevent injuries and unattended exits. Methods As part of a product development grant, a randomized pilot study was conducted to test the effectiveness of a new night monitoring system designed for informal caregivers to use in the home. Data from 53 subjects were collected at 9 points in time over a 12-month period regarding injuries and unattended home exits that occurred while the caregiver slept. Nighttime activity frequently resulted in nursing home placement. Results The night monitoring system proved a reliable adjunct to assist caregivers in managing nighttime activity. A total of 9 events (injuries or unattended home exits) occurred during the study with 6 events occurring in the control group. Using intent-to-treat analysis, there was no difference between the groups. However, in a secondary analysis based on use of the intervention, experimental subjects were 85% less likely to sustain an event than control subjects. Conclusion When nighttime activity occurred, it resulted in severe injuries sometimes associated with subsequent nursing home placement. The night monitoring system represents a new technology that caregivers can use to assist them in preventing nighttime injuries and unattended home exits in care recipients with dementia. PMID:19751921

Next-Generation Angular Distribution Models for Top-of-Atmosphere Radiative Flux Calculation from CERES Instruments: Validation

NASA Technical Reports Server (NTRS)

Su, W.; Corbett, J.; Eitzen, Z.; Liang, L.

2015-01-01

Radiative fluxes at the top of the atmosphere (TOA) from the Clouds and the Earth's Radiant Energy System (CERES) instrument are fundamental variables for understanding the Earth's energy balance and how it changes with time. TOA radiative fluxes are derived from the CERES radiance measurements using empirical angular distribution models (ADMs). This paper evaluates the accuracy of CERES TOA fluxes using direct integration and flux consistency tests. Direct integration tests show that the overall bias in regional monthly mean TOA shortwave (SW) flux is less than 0.2Wm(exp -2) and the RMSE is less than 1.1Wm(exp -2). The bias and RMSE are very similar between Terra and Aqua. The bias in regional monthly mean TOA LW fluxes is less than 0.5Wm(exp -2) and the RMSE is less than 0.8Wm(exp -)2 for both Terra and Aqua. The accuracy of the TOA instantaneous flux is assessed by performing tests using fluxes inverted from nadir- and oblique-viewing angles using CERES along-track observations and temporally and spatially matched MODIS observations, and using fluxes inverted from multi-angle MISR observations. The averaged TOA instantaneous SW flux uncertainties from these two tests are about 2.3% (1.9Wm(exp -2) over clear ocean, 1.6% (4.5Wm(exp -2) over clear land, and 2.0% (6.0Wm(exp -) over clear snow/ice; and are about 3.3% (9.0Wm(exp -2), 2.7% (8.4Wm(exp -2), and 3.7% (9.9Wm(exp -2) over ocean, land, and snow/ice under all-sky conditions. The TOA SW flux uncertainties are generally larger for thin broken clouds than for moderate and thick overcast clouds. The TOA instantaneous daytime LW flux uncertainties derived from the CERESMODIS test are 0.5% (1.5Wm(exp -2), 0.8% (2.4Wm(exp -2), and 0.7% (1.3Wm(exp -2) over clear ocean, land, and snow/ice; and are about 1.5% (3.5Wm(exp -2), 1.0% (2.9Wm(exp -2), and 1.1% (2.1Wm(exp -2) over ocean, land, and snow/ice under all-sky conditions. The TOA instantaneous nighttime LW flux uncertainties are about 0.5-1% (<2.0Wm(exp -2) for all surface types. Flux uncertainties caused by errors in scene identification are also assessed by using the collocated CALIPSO, CloudSat, CERES and MODIS data product. Errors in scene identification tend to underestimate TOA SW flux by about 0.6Wm(exp -2) and overestimate TOA daytime (nighttime) LW flux by 0.4 (0.2)Wm(exp -2) when all CERES viewing angles are considered.

Improving the effectiveness of nighttime temporary traffic control warning devices, volume 1 : evaluation of lights on nighttime work zone channelization devices.

DOT National Transportation Integrated Search

2013-10-01

Currently, the Illinois Department of Transportation (IDOT) is one of the few state transportation agencies that : require warning lights on nighttime work zone channelization devices, such as drums and barricades. The intent : of the steady-burn, am...

The relationship between in-house attending coverage and nighttime extubation following congenital heart surgery*.

PubMed

Iannucci, Glen J; Oster, Matthew E; Chanani, Nikhil K; Gillespie, Scott E; McCracken, Courtney E; Kanter, Kirk R; Mahle, William T

2014-03-01

Many cardiac ICUs have instituted 24/7 attending physician in-house coverage, which theoretically may allow for more expeditious weaning from ventilation and extubation. We aimed to determine whether this staffing strategy impacts rates of nighttime extubation and duration of mechanical ventilation. National data were obtained from the Virtual PICU System database for all patients admitted to the cardiac ICU following congenital heart surgery in 2011 who required postoperative mechanical ventilation. Contemporaneous data from our local institution were collected in addition to the Virtual PICU System data. The combined dataset (n = 2,429) was divided based on the type of nighttime staffing model in order to compare rates of nighttime extubation and duration of mechanical ventilation between units that used an in-house attending staffing strategy and those that employed nighttime residents, fellows, or midlevel providers only. Institutions that currently use 24/7 in-house attending coverage did not demonstrate statistically significant differences in rates of nighttime extubation or the duration of mechanical ventilation in comparison to units without in-house attendings. Younger patients cared for in non-in-house attending units were more likely to require reintubation. Pediatric patients who have undergone congenital heart surgery can be safely and effectively extubated without the routine presence of an attending physician. The utilization of nighttime in-house attending coverage does not appear to have significant benefits on the rate of nighttime extubation and may not reduce the duration of mechanical ventilation in units that already use in-house residents, fellows, or other midlevel providers.

Disrupted nighttime sleep in narcolepsy.

PubMed

Roth, Thomas; Dauvilliers, Yves; Mignot, Emmanuel; Montplaisir, Jacques; Paul, Josh; Swick, Todd; Zee, Phyllis

2013-09-15

Characterize disrupted nighttime sleep (DNS) in narcolepsy, an important symptom of narcolepsy. A panel of international narcolepsy experts was convened in 2011 to build a consensus characterization of DNS in patients with narcolepsy. A literature search of the Medline (1965 to date), Medline In-Process (latest weeks), Embase (1974 to date), Embase Alert (latest 8 weeks), and Biosis (1965 to date) databases was conducted using the following search terms: narcolepsy and disrupted nighttime sleep, disturbed nighttime sleep, fragmented sleep, consolidated sleep, sleep disruption, and narcolepsy questionnaire. The purpose of the literature search was to identify publications characterizing the nighttime sleep of patients with narcolepsy. The panel reviewed the literature. Nocturnal sleep can also be disturbed by REM sleep abnormalities such as vivid dreaming and REM sleep behavior disorder; however, these were not reviewed in the current paper, as we were evaluating for idiopathic sleep disturbances. The literature reviewed provide a consistent characterization of nighttime sleep in patients with narcolepsy as fragmented, with reports of frequent, brief nightly awakenings with difficulties returning to sleep and associated reports of poor sleep quality. Polysomnographic studies consistently report frequent awakenings/arousals after sleep onset, more stage 1 (S1) sleep, and more frequent shifts to S1 sleep or wake from deeper stages of sleep. The consensus of the International Experts' Panel on Narcolepsy was that DNS can be distressing for patients with narcolepsy and that treatment of DNS warrants consideration. Clinicians involved in the management of patients with narcolepsy should investigate patients' quality of nighttime sleep, give weight and consideration to patient reports of nighttime sleep experience, and consider DNS a target for treatment.

Examination of the current practice of lighting in Virginia : nighttime work zones and improving safety through the development of nighttime lighting specifications : final report.

DOT National Transportation Integrated Search

2017-09-01

This project evaluated current nighttime work zone lighting practices for limited-access highways and primary routes in Virginia through (1) an on-site evaluation of lighting levels in work zones; (2) an illuminance characterization of various commer...

Examination of the current practice of lighting in Virginia : nighttime work zones and improving safety through the development of nighttime lighting specifications : summary report.

DOT National Transportation Integrated Search

2017-09-01

This project evaluated current nighttime work zone lighting practices for limited-access highways and primary routes in Virginia through (1) an on-site evaluation of lighting levels in work zones; (2) an illuminance characterization of various commer...

Research on the effect of noise at different times of day: Models, methods and findings

NASA Technical Reports Server (NTRS)

Fields, J. M.

1985-01-01

Social surveys of residents' responses to noise at different times of day are reviewed. Some of the discrepancies in published reports about the importance of noise at different times of day are reduced when the research findings are classified according to the type of time of day reaction model, the type of time of day weight calculated and the method which is used to estimate the weight. When the estimates of nighttime weights from 12 studies are normalized, it is found that they still disagree, but do not support stronger nighttime weights than those used in existing noise indices. Challenges to common assumptions in nighttime response models are evaluated. Two of these challenges receive enough support to warrant further investigation: the impact of changes in numbers of noise events may be less at night than in the day and nighttime annoyance may be affected by noise levels in other periods. All existing social survey results in which averages of nighttime responses were plotted by nighttime noise levels are reproduced.

Evaluation of the psychometric properties of the Nighttime Symptoms of COPD Instrument.

PubMed

Mocarski, Michelle; Zaiser, Erica; Trundell, Dylan; Make, Barry J; Hareendran, Asha

2015-01-01

Nighttime symptoms can negatively impact the quality of life of patients with chronic obstructive pulmonary disease (COPD). The Nighttime Symptoms of COPD Instrument (NiSCI) was designed to measure the occurrence and severity of nighttime symptoms in patients with COPD, the impact of symptoms on nighttime awakenings, and rescue medication use. The objective of this study was to explore item reduction, inform scoring recommendations, and evaluate the psychometric properties of the NiSCI. COPD patients participating in a Phase III clinical trial completed the NiSCI daily. Item analyses were conducted using weekly mean and single day scores. Descriptive statistics (including percentage of respondents at floor/ceiling and inter-item correlations), factor analyses, and Rasch model analyses were conducted to examine item performance and scoring. Test-retest reliability was assessed for the final instrument using the intraclass correlation coefficient (ICC). Correlations with assessments conducted during study visits were used to evaluate convergent and known-groups validity. Data from 1,663 COPD patients aged 40-93 years were analyzed. Item analyses supported the generation of four scores. A one-factor structure was confirmed with factor analysis and Rasch analysis for the symptom severity score. Test-retest reliability was confirmed for the six-item symptom severity (ICC, 0.85), number of nighttime awakenings (ICC, 0.82), and rescue medication (ICC, 0.68) scores. Convergent validity was supported by significant correlations between the NiSCI, St George's Respiratory Questionnaire, and Exacerbations of Chronic Obstructive Pulmonary Disease Tool-Respiratory Symptoms scores. The results suggest that the NiSCI can be used to determine the severity of nighttime COPD symptoms, the number of nighttime awakenings due to COPD symptoms, and the nighttime use of rescue medication. The NiSCI is a reliable and valid instrument to evaluate these concepts in COPD patients in clinical trials and clinical practice. Scoring recommendations and steps for further research are discussed.

Sleep and autonomic nervous system changes - enhanced cardiac sympathetic modulations during sleep in permanent night shift nurses.

PubMed

Chung, Min-Huey; Kuo, Terry B J; Hsu, Nanly; Chu, Hsin; Chou, Kuei-Ru; Yang, Cheryl C H

2009-05-01

Disturbed sleep is the most common problem among the many health-related effects of shift work, with shift workers clearly having higher rates of cardiac disorders. However, the possible mechanism underlying the related health effects of shift work has yet to be examined. Consequently, this study aimed to explore the influence of long-term night shift work on the sleep patterns of nurses and their cardiac autonomic nervous system during sleep. Our sample comprised ten permanent night shift and ten regular morning shift nurses. Nurses slept in their dormitory where they were allowed to sleep and wake spontaneously. All sleep parameters were digitized using an ambulatory polysomnographic recorder. Using sleep patterns and heart rate variability, the day- and nighttime sleep of permanent night shift nurses were compared with the nighttime sleep of regular morning shift nurses. Compared with the nighttime sleep of regular morning shift nurses, the pattern of daytime sleep of permanent night shift nurses showed significantly lower sleep onset latency. Permanent night shift nurses' daytime sleep also had greater proportions of Stage 3 and 4 (deep sleep), and arousal index than recorded during their nighttime sleep. Both the low frequency and low to high frequency ratio of the nighttime sleep of night shift nurses were significantly higher during periods of non-rapid eye movement (NREM) sleep than the nighttime sleep of morning shift workers. In addition, the electroencephalography delta-power of the nighttime sleep of night shift nurses was significantly lower during the first NREM episode sleep than those of both the daytime sleep of night shift workers and the nighttime sleep of morning shift nurses. Permanent night shift nurses have higher sympathetic activity during nighttime sleep than regular morning shift nurses. Night shift working may have effects on the sleeping patterns of nurses in the long run, inducing higher cardiac sympathetic regulation.

Nighttime BP in Elderly Individuals with Prediabetes/Diabetes with and without CKD: The HEIJO-KYO Study.

PubMed

Obayashi, Kenji; Saeki, Keigo; Kurumatani, Norio

2016-05-06

and objectives Although previous studies suggested that nighttime BP is elevated in diabetes mellitus, the association between prediabetes and nighttime BP remains unclear. In addition, the relationship between diabetic status, renal function, and nighttime BP has not been evaluated in large populations. In this cross-sectional study, we assessed diabetic status, renal function, and ambulatory BP parameters among 1081 community-dwelling elderly individuals (mean age, 71.8±7.0 years). Participants were classified into six categories based on diabetic status (normoglycemia, prediabetes, or diabetes mellitus) and renal function (normal function or CKD). BP was measured at 30-minute intervals for 48 hours using a validated ambulatory recorder. The mean nighttime systolic BP (SBP) was 115.7±16.1 mmHg. The multivariable analysis, adjusted for age, sex, smoking status, and daytime SBP, revealed that, compared with participants with normoglycemia but without CKD (n=378), mean nighttime SBP was significantly higher in participants with both prediabetes and CKD (n=93) by 2.9 mmHg (95% confidence interval [95% CI], 0.2 to 5.6; P=0.03) and in patients with both diabetes mellitus and CKD (n=30) by 7.8 mmHg (95% CI, 3.5 to 12.2; P<0.001) but not in participants with both normoglycemia and CKD (n=75), participants with prediabetes without CKD (n=374), or patients with diabetes mellitus without CKD (n=131). Notably, the multivariable analysis indicated that the interaction terms of diabetic status and renal function were significantly associated with nighttime SBP (P=0.03). Nighttime SBP was significantly higher in participants with prediabetes and CKD but not in participants with prediabetes without CKD, compared with participants with normoglycemia and without CKD. In addition, a significant interaction effect of diabetic status and renal function on nighttime SBP was detected in a general elderly population. Copyright © 2016 by the American Society of Nephrology.

Nighttime BP in Elderly Individuals with Prediabetes/Diabetes with and without CKD: The HEIJO-KYO Study

PubMed Central

Saeki, Keigo; Kurumatani, Norio

2016-01-01

Background and objectives Although previous studies suggested that nighttime BP is elevated in diabetes mellitus, the association between prediabetes and nighttime BP remains unclear. In addition, the relationship between diabetic status, renal function, and nighttime BP has not been evaluated in large populations. Design, setting, participants, & measurements In this cross-sectional study, we assessed diabetic status, renal function, and ambulatory BP parameters among 1081 community-dwelling elderly individuals (mean age, 71.8±7.0 years). Participants were classified into six categories based on diabetic status (normoglycemia, prediabetes, or diabetes mellitus) and renal function (normal function or CKD). BP was measured at 30-minute intervals for 48 hours using a validated ambulatory recorder. Results The mean nighttime systolic BP (SBP) was 115.7±16.1 mmHg. The multivariable analysis, adjusted for age, sex, smoking status, and daytime SBP, revealed that, compared with participants with normoglycemia but without CKD (n=378), mean nighttime SBP was significantly higher in participants with both prediabetes and CKD (n=93) by 2.9 mmHg (95% confidence interval [95% CI], 0.2 to 5.6; P=0.03) and in patients with both diabetes mellitus and CKD (n=30) by 7.8 mmHg (95% CI, 3.5 to 12.2; P<0.001) but not in participants with both normoglycemia and CKD (n=75), participants with prediabetes without CKD (n=374), or patients with diabetes mellitus without CKD (n=131). Notably, the multivariable analysis indicated that the interaction terms of diabetic status and renal function were significantly associated with nighttime SBP (P=0.03). Conclusions Nighttime SBP was significantly higher in participants with prediabetes and CKD but not in participants with prediabetes without CKD, compared with participants with normoglycemia and without CKD. In addition, a significant interaction effect of diabetic status and renal function on nighttime SBP was detected in a general elderly population. PMID:26915915

Disrupted Nighttime Sleep in Narcolepsy

PubMed Central

Roth, Thomas; Dauvilliers, Yves; Mignot, Emmanuel; Montplaisir, Jacques; Paul, Josh; Swick, Todd; Zee, Phyllis

2013-01-01

Study Objectives: Characterize disrupted nighttime sleep (DNS) in narcolepsy, an important symptom of narcolepsy. Methods: A panel of international narcolepsy experts was convened in 2011 to build a consensus characterization of DNS in patients with narcolepsy. A literature search of the Medline (1965 to date), Medline In-Process (latest weeks), Embase (1974 to date), Embase Alert (latest 8 weeks), and Biosis (1965 to date) databases was conducted using the following search terms: narcolepsy and disrupted nighttime sleep, disturbed nighttime sleep, fragmented sleep, consolidated sleep, sleep disruption, and narcolepsy questionnaire. The purpose of the literature search was to identify publications characterizing the nighttime sleep of patients with narcolepsy. The panel reviewed the literature. Nocturnal sleep can also be disturbed by REM sleep abnormalities such as vivid dreaming and REM sleep behavior disorder; however, these were not reviewed in the current paper, as we were evaluating for idiopathic sleep disturbances. Results: The literature reviewed provide a consistent characterization of nighttime sleep in patients with narcolepsy as fragmented, with reports of frequent, brief nightly awakenings with difficulties returning to sleep and associated reports of poor sleep quality. Polysomnographic studies consistently report frequent awakenings/arousals after sleep onset, more stage 1 (S1) sleep, and more frequent shifts to S1 sleep or wake from deeper stages of sleep. The consensus of the International Experts' Panel on Narcolepsy was that DNS can be distressing for patients with narcolepsy and that treatment of DNS warrants consideration. Conclusions: Clinicians involved in the management of patients with narcolepsy should investigate patients' quality of nighttime sleep, give weight and consideration to patient reports of nighttime sleep experience, and consider DNS a target for treatment. Citation: Roth T; Dauvilliers Y; Mignot E; Montplaisir J; Paul J; Swick T; Zee P. Disrupted nighttime sleep in narcolepsy. J Clin Sleep Med 2013;9(9):955-965. PMID:23997709

Differences in night-time and daytime ambulatory blood pressure when diurnal periods are defined by self-report, fixed-times, and actigraphy: Improving the Detection of Hypertension study.

PubMed

Booth, John N; Muntner, Paul; Abdalla, Marwah; Diaz, Keith M; Viera, Anthony J; Reynolds, Kristi; Schwartz, Joseph E; Shimbo, Daichi

2016-02-01

To determine whether defining diurnal periods by self-report, fixed-time, or actigraphy produce different estimates of night-time and daytime ambulatory blood pressure (ABP). Over a median of 28 days, 330 participants completed two 24-h ABP and actigraphy monitoring periods with sleep diaries. Fixed night-time and daytime periods were defined as 0000-0600 h and 1000-2000 h, respectively. Using the first ABP period, within-individual differences for mean night-time and daytime ABP and kappa statistics for night-time and daytime hypertension (systolic/diastolic ABP≥120/70 mmHg and ≥135/85 mmHg, respectively) were estimated comparing self-report, fixed-time, or actigraphy for defining diurnal periods. Reproducibility of ABP was also estimated. Within-individual mean differences in night-time systolic ABP were small, suggesting little bias, when comparing the three approaches used to define diurnal periods. The distribution of differences, represented by 95% confidence intervals (CI), in night-time systolic and diastolic ABP and daytime systolic and diastolic ABP was narrowest for self-report versus actigraphy. For example, mean differences (95% CI) in night-time systolic ABP for self-report versus fixed-time was -0.53 (-6.61, +5.56) mmHg, self-report versus actigraphy was 0.91 (-3.61, +5.43) mmHg, and fixed-time versus actigraphy was 1.43 (-5.59, +8.46) mmHg. Agreement for night-time and daytime hypertension was highest for self-report versus actigraphy: kappa statistic (95% CI) = 0.91 (0.86,0.96) and 1.00 (0.98,1.00), respectively. The reproducibility of mean ABP and hypertension categories was similar using each approach. Given the high agreement with actigraphy, these data support using self-report to define diurnal periods on ABP monitoring. Further, the use of fixed-time periods may be a reasonable alternative approach.

Green laser pointers for visual astronomy: how much power is enough?

PubMed

Bará, Salvador; Robles, Marisol; Tejelo, Isabel; Marzoa, Ramón I; González, Héctor

2010-02-01

Green laser pointers with output powers in the tens to hundreds of milliwatt (mW) range, clearly exceeding the limiting 5 mW of American National Standards Institute class 3a (International Electrotechnical Commission class 3R), are now easily available in the global market. They are increasingly being used in public sky observations and other nighttime outreach activities by educators and science communicators in countries where their use is not well regulated, despite the fact that such high power levels may represent a potential threat to visual health. The purpose of this study was to determine the output power reasonably required to perform satisfactorily this kind of activities. Twenty-three observers were asked to vary continuously the output power of a green laser source (wavelength 532 nm) until clearly seeing the laser beam propagating skyward through the atmosphere in a heavily light-polluted urban setting. Measurements were conducted with observers of a wide range of ages (9 to 56 years), refractions (spherical equivalents -8.50 to +1.50 diopters), and previous expertise in using lasers as pointing devices outdoors (from no experience to professional astronomers). Two measurement runs were made in different nights under different meteorological conditions. The output power chosen by observers in the first run (11 observers) averaged to 1.84 mW (+/-0.68 mW, 1 SD). The second run (17 observers) averaged to 2.91 mW (+/-1.54 mW). The global average was 2.38 mW (+/-1.30 mW). Only one observer scored 5.6 mW, just above the class 3a limit. The power chosen by the remaining 22 observers ranged from 1.37 to 3.53 mW. Green laser pointers with output powers below 5 mW (laser classes American National Standards Institute 3a or International Electrotechnical Commission 3R) appear to be sufficient for use in educational nighttime outdoors activities, providing enough bright beams at reasonable safety levels.

Changes to pediatric clerkships' nighttime structure after introduction of the 2011 ACGME resident duty hour standards.

PubMed

Smith, Andrew; Stevenson, Adam

2014-01-01

To report changes in pediatric clerkship nighttime clinical structures before and after implementation of the 2011 Accreditation Council for Graduate Medical Education (ACGME) resident duty hour standards. As part of the 2011 Council on Medical Student Education in Pediatrics (COMSEP) member annual survey, we surveyed leaders of pediatric undergraduate medical education on their medical school's current nighttime clinical structure, changes in nighttime structure between 2010 and 2011, and their school's student duty hour standards. Fifty-six percent (n = 83) of Liaison Committee for Medical Education (LCME)-accredited medical schools responded to the survey. Of received responses, 98% of pediatric clerkships have some form of nighttime clinical experience; 49% of clerkships have medical students stay late, 24% of clerkships utilize night shifts, and 16% use a traditional call structure. Forty-five percent of clerkships report changing their nighttime clinical experience after implementation of the 2011 ACGME duty hour standards; 46% of clerkships that changed had previously used traditional call. Seventy-six percent of clerkships report having medical student duty hour standards at their medical school. The majority of pediatric clerkships in our survey include nighttime clinical experiences in their curriculum, although variability exists in the type of structure. Additionally, the new ACGME duty hour standards appear to affect clerkships directors' choice of structure. Copyright © 2014 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

Prototype active scanner for nighttime oil spill mapping and classification

NASA Technical Reports Server (NTRS)

Sandness, G. A.; Ailes, S. B.

1977-01-01

A prototype, active, aerial scanner system was constructed for nighttime water pollution detection and nighttime multispectral imaging of the ground. An arc lamp was used to produce the transmitted light and four detector channels provided a multispectral measurement capability. The feasibility of the design concept was demonstrated by laboratory and flight tests of the prototype system.

Relief of Night-time Symptoms Associated With Gastroesophageal Reflux Disease Following 4 Weeks of Treatment With Pantoprazole Magnesium: The Mexican Gastroesophageal Reflux Disease Working Group

PubMed Central

Orr, William; Vargas-Romero, José Antonio; Remes-Troche, José María; Morales-Arámbula, Miguel; Soto-Pérez, Julio César; Mateos-Pérez, Gualberto; Sobrino-Cossío, Sergio; Teramoto-Matsubara, Oscar; López-Colombo, Aurelio; Orozco-Gamiz, Antonio; Saez-Ríos, Adolfo; Arellano-Plancarte, Araceli; Chiu-Ugalde, Jazmin; Tholen, Anne; Horbach, Silke; Lundberg, Lars; Fass, Ronnie

2014-01-01

Background/Aims To evaluate the effectiveness of pantoprazole magnesium (pantoprazole-Mg) 40 mg in the relief of esophageal and extra-esophageal symptoms of gastroesophageal reflux disease (GERD), particularly night-time symptoms. Methods Patients (aged 18-50 years) with 3-month history of heartburn and/or acid regurgitation plus at least one other symptom in the last week were enrolled in a nationwide, prospective and observational study in Mexico. Patients received pantoprazole-Mg 40 mg once daily during 4 weeks. Symptoms were assessed through a physician-administered structured interview and the patient-completed ReQuest in Practice™ questionnaire. Night-time GERD was defined as arousal from sleep during the night due to GERD-associated symptoms. Results Out of 4,343 patients included at basal visit, 3,665 were considered for the effectiveness per protocol analysis. At baseline, patients had a median of 8 GERD related symptoms. Patients with night-time GERD symptoms (42.7%) were more likely to have extra-esophageal symptoms (P < 0.001) than other GERD patients. Pantoprazole-Mg 40 mg once daily for 4 weeks improved a broad range of GERD-associated symptoms from baseline (80% reduction on physicians assessments; 68-77% reduction on ReQuest in Practice™ dimensions), including both day- and night-time GERD symptoms; improvements were the greatest for extra-esophageal symptoms in patients with night-time symptoms. Pantoprazole-Mg was well tolerated. Conclusions Pantoprazole-Mg 40 mg significantly improved a broad range of esophageal and extra-esophageal GERD related symptoms including sleep disturbances, as well as well-being, in patients with daytime or night-time GERD, making it a good option for patients with GERD, especially when extra-esophageal and night-time symptoms are present. PMID:24466446

Relief of Night-time Symptoms Associated With Gastroesophageal Reflux Disease Following 4 Weeks of Treatment With Pantoprazole Magnesium: The Mexican Gastroesophageal Reflux Disease Working Group.

PubMed

López-Alvarenga, Juan Carlos; Orr, William; Vargas-Romero, José Antonio; Remes-Troche, José María; Morales-Arámbula, Miguel; Soto-Pérez, Julio César; Mateos-Pérez, Gualberto; Sobrino-Cossío, Sergio; Teramoto-Matsubara, Oscar; López-Colombo, Aurelio; Orozco-Gamiz, Antonio; Saez-Ríos, Adolfo; Arellano-Plancarte, Araceli; Chiu-Ugalde, Jazmin; Tholen, Anne; Horbach, Silke; Lundberg, Lars; Fass, Ronnie

2014-01-01

To evaluate the effectiveness of pantoprazole magnesium (pantoprazole-Mg) 40 mg in the relief of esophageal and extra-esophageal symptoms of gastroesophageal reflux disease (GERD), particularly night-time symptoms. Patients (aged 18-50 years) with 3-month history of heartburn and/or acid regurgitation plus at least one other symptom in the last week were enrolled in a nationwide, prospective and observational study in Mexico. Patients received pantoprazole-Mg 40 mg once daily during 4 weeks. Symptoms were assessed through a physician-administered structured interview and the patient-completed ReQuest in Practice™ questionnaire. Night-time GERD was defined as arousal from sleep during the night due to GERD-associated symptoms. Out of 4,343 patients included at basal visit, 3,665 were considered for the effectiveness per protocol analysis. At baseline, patients had a median of 8 GERD related symptoms. Patients with night-time GERD symptoms (42.7%) were more likely to have extra-esophageal symptoms (P < 0.001) than other GERD patients. Pantoprazole-Mg 40 mg once daily for 4 weeks improved a broad range of GERD-associated symptoms from baseline (80% reduction on physicians assessments; 68-77% reduction on ReQuest in Practice™ dimensions), including both day- and night-time GERD symptoms; improvements were the greatest for extra-esophageal symptoms in patients with night-time symptoms. Pantoprazole-Mg was well tolerated. Pantoprazole-Mg 40 mg significantly improved a broad range of esophageal and extra-esophageal GERD related symptoms including sleep disturbances, as well as well-being, in patients with daytime or night-time GERD, making it a good option for patients with GERD, especially when extra-esophageal and night-time symptoms are present.

Quantifying the erosion of natural darkness in the global protected area system.

PubMed

Gaston, Kevin J; Duffy, James P; Bennie, Jonathan

2015-08-01

The nighttime light environment of much of the earth has been transformed by the introduction of electric lighting. This impact continues to spread with growth in the human population and extent of urbanization. This has profound consequences for organismal physiology and behavior and affects abundances and distributions of species, community structure, and likely ecosystem functions and processes. Protected areas play key roles in buffering biodiversity from a wide range of anthropogenic pressures. We used a calibration of a global satellite data set of nighttime lights to determine how well they are fulfilling this role with regard to artificial nighttime lighting. Globally, areas that are protected tend to be darker at night than those that are not, and, with the exception of Europe, recent regional declines in the proportion of the area that is protected and remains dark have been small. However, much of these effects result from the major contribution to overall protected area coverage by the small proportion of individual protected areas that are very large. Thus, in Europe and North America high proportions of individual protected areas (>17%) have exhibited high levels of nighttime lighting in all recent years, and in several regions (Europe, Asia, South and Central America) high proportions of protected areas (32-42%) have had recent significant increases in nighttime lighting. Limiting and reversing the erosion of nighttime darkness in protected areas will require routine consideration of nighttime conditions when designating and establishing new protected areas; establishment of appropriate buffer zones around protected areas where lighting is prohibited; and landscape level reductions in artificial nighttime lighting, which is being called for in general to reduce energy use and economic costs. © 2015 Society for Conservation Biology.

Decreased concentration of serum melatonin in nighttime compared with daytime female medical technologists in South Korea.

PubMed

Song, GiSeon; Yoon, Kyong-Ah; Chi, HyunYoung; Roh, Jaehoon; Kim, Jin-Hee

2016-01-01

Working during the night can disrupt the normal circadian rhythm by altering the melatonin level. A low level of melatonin is associated with an increased risk of cancer, possibly by decreasing the expression of tumor-suppressor genes, such as p53. To determine whether nighttime work is associated with melatonin level in serum as well as the expression of related genetic markers, we enrolled 100 female nighttime medical technologists employed at a hospital in South Korea. Melatonin concentration and melatonin receptor 1 (MT1) expression were significantly lower in nighttime than in daytime workers (1.84 pg/mL versus 4.04 pg/mL; 1.16 versus 1.61, respectively). However, p53 expression showed no difference between the groups. In summary, nighttime work could be an important risk factor for circadian disruption, but not a direct risk factor for cancer in medical technologists in South Korea.

Poor ultrafiltration during nighttime dialysis in CAPD patients and its effects on fluid balance.

PubMed

Pagé, D E; Levine, D Z

1993-01-01

To evaluate fluid retention during the long nighttime peritoneal dwell in continuous ambulatory peritoneal dialysis (CAPD) patients, we measured remaining volumes in 70 patients. In only 50% of these patients were more than 2 L of fluid recovered; in 30% between 1.5 and 2 L were recovered; and in 17% of patients we retrieved less than 1.5 L of peritoneal fluid. In 3 of these patients, who were edematous and had marked pitting edema, we shortened the nighttime dwell by having the patients awaken after 4 hours and drain the dwell. This resulted in 3-5 kg of weight loss in each patient, when compared with each patient's previous use of long nighttime dwells. Finally, we propose in this report two automated methods whereby the period of nighttime dialysis can be controlled, while patients sleep, using a system of timer clamps.

Low-Income Mothers' Nighttime and Weekend Work: Daily Associations with Child Behavior, Mother-Child Interactions, and Mood

ERIC Educational Resources Information Center

Gassman-Pines, Anna

2011-01-01

This study investigated low-income mothers' daily nighttime and weekend work and family outcomes. Sixty-one mothers of preschool-aged children reported daily on work hours, mood, mother-child interaction, and child behavior for two weeks (N = 724 person-days). Although nighttime and weekend work are both nonstandard schedules, results showed…

CubeSat Nighttime Earth Observations

NASA Astrophysics Data System (ADS)

Pack, D. W.; Hardy, B. S.; Longcore, T.

2017-12-01

Satellite monitoring of visible emissions at night has been established as a useful capability for environmental monitoring and mapping the global human footprint. Pioneering work using Defense Meteorological Support Program (DMSP) sensors has been followed by new work using the more capable Visible Infrared Imaging Radiometer Suite (VIIRS). Beginning in 2014, we have been investigating the ability of small visible light cameras on CubeSats to contribute to nighttime Earth science studies via point-and-stare imaging. This paper summarizes our recent research using a common suite of simple visible cameras on several AeroCube satellites to carry out nighttime observations of urban areas and natural gas flares, nighttime weather (including lighting), and fishing fleet lights. Example results include: urban image examples, the utility of color imagery, urban lighting change detection, and multi-frame sequences imaging nighttime weather and large ocean areas with extensive fishing vessel lights. Our results show the potential for CubeSat sensors to improve monitoring of urban growth, light pollution, energy usage, the urban-wildland interface, the improvement of electrical power grids in developing countries, light-induced fisheries, and oil industry flare activity. In addition to orbital results, the nighttime imaging capabilities of new CubeSat sensors scheduled for launch in October 2017 are discussed.

Bud break responds more strongly to daytime than night-time temperature under asymmetric experimental warming.

PubMed

Rossi, Sergio; Isabel, Nathalie

2017-01-01

Global warming is diurnally asymmetric, leading to a less cold, rather than warmer, climate. We investigated the effects of asymmetric experimental warming on plant phenology by testing the hypothesis that daytime warming is more effective in advancing bud break than night-time warming. Bud break was monitored daily in Picea mariana seedlings belonging to 20 provenances from Eastern Canada and subjected to daytime and night-time warming in growth chambers at temperatures varying between 8 and 16 °C. The higher advancements of bud break and shorter times required to complete the phenological phases occurred with daytime warming. Seedlings responded to night-time warming, but still with less advancement of bud break than under daytime warming. No advancement was observed when night-time warming was associated with a daytime cooling. The effect of the treatments was uniform across provenances. Our observations realized under controlled conditions allowed to experimentally demonstrate that bud break can advance under night-time warming, but to a lesser extent than under daytime warming. Prediction models using daily timescales could neglect the diverging influence of asymmetric warming and should be recalibrated for higher temporal resolutions. © 2016 John Wiley & Sons Ltd.

Interspecific variation in nighttime transpiration and stomatal conductance in a mixed New England deciduous forest.

PubMed

Daley, Michael J; Phillips, Nathan G

2006-04-01

Transpiration is generally assumed to be insignificant at night when stomata close in response to the lack of photosynthetically active radiation. However, there is increasing evidence that the stomata of some species remain open at night, which would allow for nighttime transpiration if there were a sufficient environmental driving force. We examined nighttime water use in co-occurring species in a mixed deciduous stand at Harvard Forest, MA, using whole-tree and leaf-level measurements. Diurnal whole-tree water use was monitored continuously with Granier-style sap flux sensors in paper birch (Betula papyrifera Marsh.), red oak (Quercus rubra L.) and red maple (Acer rubrum L.). An analysis was conducted in which nighttime water flux could be partitioned between refilling of internal water stores and transpiration. Substantial nighttime sap flux was observed in all species and much of this flux was attributed to the refilling of depleted water stores. However, in paper birch, nighttime sap flux frequently exceeded recharge estimates. Over 10% of the total daily sap flux during the growing season was due to transpiration at night in paper birch. Nighttime sap flux was over 8% of the total daily flux in red oak and 2% in red maple; however, this flux was mainly associated with recharge. On nights with elevated vapor pressure deficit, sap flux continued through the night in paper birch, whereas it reached zero during the night in red oak and red maple. Measurements of leaf-level gas exchange on a night with elevated vapor pressure deficit showed stomatal conductance dropping by only 25% in paper birch, while approaching zero in red oak and red maple. The study highlighted differences in ecophysiological controls on sap flux exerted by co-occurring species. Paper birch is a fast-growing, shade-intolerant species with an earlier successional status than red oak and red maple. Risking water loss through nighttime transpiration may provide paper birch with an ecological advantage by enabling the species to maximize photosynthesis and support rapid growth. Nighttime transpiration may also be a mechanism for delivering oxygen to respiring cells in the deep sapwood of paper birch.

FDTD Modeling of LEMP Propagation in the Earth-Ionosphere Waveguide With Emphasis on Realistic Representation of Lightning Source

NASA Astrophysics Data System (ADS)

Tran, Thang H.; Baba, Yoshihiro; Somu, Vijaya B.; Rakov, Vladimir A.

2017-12-01

The finite difference time domain (FDTD) method in the 2-D cylindrical coordinate system was used to compute the nearly full-frequency-bandwidth vertical electric field and azimuthal magnetic field waveforms produced on the ground surface by lightning return strokes. The lightning source was represented by the modified transmission-line model with linear current decay with height, which was implemented in the FDTD computations as an appropriate vertical phased-current-source array. The conductivity of atmosphere was assumed to increase exponentially with height, with different conductivity profiles being used for daytime and nighttime conditions. The fields were computed at distances ranging from 50 to 500 km. Sky waves (reflections from the ionosphere) were identified in computed waveforms and used for estimation of apparent ionospheric reflection heights. It was found that our model reproduces reasonably well the daytime electric field waveforms measured at different distances and simulated (using a more sophisticated propagation model) by Qin et al. (2017). Sensitivity of model predictions to changes in the parameters of atmospheric conductivity profile, as well as influences of the lightning source characteristics (current waveshape parameters, return-stroke speed, and channel length) and ground conductivity were examined.

CALIPSO Observations of Transatlantic Dust: Vertical Stratification and Effect of Clouds

NASA Technical Reports Server (NTRS)

Yang, Weidong; Marshak, Alexander; Varnai, Tamas; Kalashnikova, Olga V.; Kostinski, Alexander B.

2014-01-01

We use CALIOP nighttime measurements of lidar backscatter, color and depolarization ratios, as well as particulate retrievals during the summer of 2007 to study transatlantic dust properties downwind of Saharan sources, and to examine the influence of nearby clouds on dust. Our analysis suggests that (1) under clear skies, while lidar backscatter and color ratio do not change much with altitude and longitude in the Saharan Air Layer (SAL), depolarization ratio increases with altitude and decreases westward in the SAL (2) the vertical lapse rate of dust depolarization ratio, introduced here, increases within SAL as plumes move westward (3) nearby clouds barely affect the backscatter and color ratio of dust volumes within SAL but not so below SAL. Moreover, the presence of nearby clouds tends to decrease the depolarization of dust volumes within SAL. Finally, (4) the odds of CALIOP finding dust below SAL next to clouds are about of those far away from clouds. This feature, together with an apparent increase in depolarization ratio near clouds, indicates that particles in some dust volumes loose asphericity in the humid air near clouds, and cannot be identified by CALIPSO as dust.

GSFC_20180130_M12842_Supermoon

NASA Image and Video Library

2018-01-30

Get ready for the Super Blue Blood Moon! Our closest celestial neighbor is always a wondrous sight, but on the morning of Jan. 31, 2018, three special lunar events are all happening at the same time, providing an excellent excuse to go out and enjoy the nighttime sky. 1 - The full Moon is near the closest point of its orbit so it appears a little larger than usual, what many call a Supermoon. 2 - It’s the second full Moon of the month, what many call a Blue Moon, though the Moon is not literally blue. 3 - There’s a total lunar eclipse, what many call a Blood Moon, visible before sunrise for the western half of the U.S. and other countries near the Pacific. During a total lunar eclipse, the Moon crosses through the shadow of the Earth and LITERALLY appears red as it reflects all of Earth’s sunrises and sunsets. Join NASA scientists Michelle Thaller and Noah Petro live from the Goddard Space Flight Center as we discuss where, when, and how to view this lunar extravaganza and the latest Moon science brought to us by NASA’s Lunar Reconnaissance Orbiter.

Long-term dim light during nighttime changes activity patterns and space use in experimental small mammal populations.

PubMed

Hoffmann, Julia; Palme, Rupert; Eccard, Jana Anja

2018-07-01

Artificial light at night (ALAN) is spreading worldwide and thereby is increasingly interfering with natural dark-light cycles. Meanwhile, effects of very low intensities of light pollution on animals have rarely been investigated. We explored the effects of low intensity ALAN over seven months in eight experimental bank vole (Myodes glareolus) populations in large grassland enclosures over winter and early breeding season, using LED garden lamps. Initial populations consisted of eight individuals (32 animals per hectare) in enclosures with or without ALAN. We found that bank voles under ALAN experienced changes in daily activity patterns and space use behavior, measured by automated radiotelemetry. There were no differences in survival and body mass, measured with live trapping, and none in levels of fecal glucocorticoid metabolites. Voles in the ALAN treatment showed higher activity at night during half moon, and had larger day ranges during new moon. Thus, even low levels of light pollution as experienced in remote areas or by sky glow can lead to changes in animal behavior and could have consequences for species interactions. Copyright © 2018 Elsevier Ltd. All rights reserved.

GeMS: Gemini Mcao System: current status and commissioning plans

NASA Astrophysics Data System (ADS)

Boccas, Maxime; Rigaut, François; Gratadour, Damien; d'Orgeville, Céline; Bec, Matthieu; Daruich, Felipe; Perez, Gabriel; Arriagada, Gustavo; Bombino, Stacy; Carter, Chris; Cavedoni, Chas; Collao, Fabian; Collins, Paul; Diaz, Pablo; Ebbers, Angelic; Galvez, Ramon; Gausachs, Gaston; Hardash, Steve; James, Eric; Karewicz, Stan; Lazo, Manuel; Maltes, Diego; Mouser, Ron; Rogers, Rolando; Rojas, Roberto; Sheehan, Michael; Trancho, Gelys; Vergara, Vicente; Vucina, Tomislav

2008-07-01

The Gemini Multi-Conjugate Adaptive Optics project was launched in April 1999 to become the Gemini South AO facility in Chile. The system includes 5 laser guide stars, 3 natural guide stars and 3 deformable mirrors optically conjugated at 0, 4.5 and 9km to achieve near-uniform atmospheric compensation over a 1 arc minute square field of view. Sub-contracted systems with vendors were started as early as October 2001 and were all delivered by July 2007, but for the 50W laser (due around September 2008). The in-house development began in January 2006, and is expected to be completed by the end of 2008 to continue with integration and testing (I&T) on the telescope. The on-sky commissioning phase is scheduled to start during the first half of 2009. In this general overview, we will first describe the status of each subsystem with their major requirements, risk areas and achieved performance. Next we will present our plan to complete the project by reviewing the remaining steps through I&T and commissioning on the telescope, both during day-time and at night-time. Finally, we will summarize some management activities like schedules, resources and conclude with some lessons learned.

Daytime warming has stronger negative effects on soil nematodes than night-time warming.

PubMed

Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

2017-03-07

Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming.

Daytime warming has stronger negative effects on soil nematodes than night-time warming.

PubMed

Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

2017-03-20

Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming.

Daytime warming has stronger negative effects on soil nematodes than night-time warming

PubMed Central

Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

2017-01-01

Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming. PMID:28317914

Daytime warming has stronger negative effects on soil nematodes than night-time warming

NASA Astrophysics Data System (ADS)

Yan, Xiumin; Wang, Kehong; Song, Lihong; Wang, Xuefeng; Wu, Donghui

2017-03-01

Warming of the climate system is unequivocal, that is, stronger warming during night-time than during daytime. Here we focus on how soil nematodes respond to the current asymmetric warming. A field infrared heating experiment was performed in the western of the Songnen Plain, Northeast China. Three warming modes, i.e. daytime warming, night-time warming and diurnal warming, were taken to perform the asymmetric warming condition. Our results showed that the daytime and diurnal warming treatment significantly decreased soil nematodes density, and night-time warming treatment marginally affected the density. The response of bacterivorous nematode and fungivorous nematode to experimental warming showed the same trend with the total density. Redundancy analysis revealed an opposite effect of soil moisture and soil temperature, and the most important of soil moisture and temperature in night-time among the measured environment factors, affecting soil nematode community. Our findings suggested that daily minimum temperature and warming induced drying are most important factors affecting soil nematode community under the current global asymmetric warming.

Nighttime images fusion based on Laplacian pyramid

NASA Astrophysics Data System (ADS)

Wu, Cong; Zhan, Jinhao; Jin, Jicheng

2018-02-01

This paper expounds method of the average weighted fusion, image pyramid fusion, the wavelet transform and apply these methods on the fusion of multiple exposures nighttime images. Through calculating information entropy and cross entropy of fusion images, we can evaluate the effect of different fusion. Experiments showed that Laplacian pyramid image fusion algorithm is suitable for processing nighttime images fusion, it can reduce the halo while preserving image details.

Modelled hydraulic redistribution by sunflower (Helianthus annuus L.) matches observed data only after including night-time transpiration.

PubMed

Neumann, Rebecca B; Cardon, Zoe G; Teshera-Levye, Jennifer; Rockwell, Fulton E; Zwieniecki, Maciej A; Holbrook, N Michele

2014-04-01

The movement of water from moist to dry soil layers through the root systems of plants, referred to as hydraulic redistribution (HR), occurs throughout the world and is thought to influence carbon and water budgets and ecosystem functioning. The realized hydrologic, biogeochemical and ecological consequences of HR depend on the amount of redistributed water, whereas the ability to assess these impacts requires models that correctly capture HR magnitude and timing. Using several soil types and two ecotypes of sunflower (Helianthus annuus L.) in split-pot experiments, we examined how well the widely used HR modelling formulation developed by Ryel et al. matched experimental determination of HR across a range of water potential driving gradients. H. annuus carries out extensive night-time transpiration, and although over the last decade it has become more widely recognized that night-time transpiration occurs in multiple species and many ecosystems, the original Ryel et al. formulation does not include the effect of night-time transpiration on HR. We developed and added a representation of night-time transpiration into the formulation, and only then was the model able to capture the dynamics and magnitude of HR we observed as soils dried and night-time stomatal behaviour changed, both influencing HR. © 2013 John Wiley & Sons Ltd.

Modeled hydraulic redistribution by Helianthus annuus L. matches observed data only after model modification to include nighttime transpiration

NASA Astrophysics Data System (ADS)

Neumann, R. B.; Cardon, Z. G.; Rockwell, F. E.; Teshera-Levye, J.; Zwieniecki, M.; Holbrook, N. M.

2013-12-01

The movement of water from moist to dry soil layers through the root systems of plants, referred to as hydraulic redistribution (HR), occurs throughout the world and is thought to influence carbon and water budgets and ecosystem functioning. The realized hydrologic, biogeochemical, and ecological consequences of HR depend on the amount of redistributed water, while the ability to assess these impacts requires models that correctly capture HR magnitude and timing. Using several soil types and two eco-types of Helianthus annuus L. in split-pot experiments, we examined how well the widely used HR modeling formulation developed by Ryel et al. (2002) could match experimental determination of HR across a range of water potential driving gradients. H. annuus carries out extensive nighttime transpiration, and though over the last decade it has become more widely recognized that nighttime transpiration occurs in multiple species and many ecosystems, the original Ryel et al. (2002) formulation does not include the effect of nighttime transpiration on HR. We developed and added a representation of nighttime transpiration into the formulation, and only then was the model able to capture the dynamics and magnitude of HR we observed as soils dried and nighttime stomatal behavior changed, both influencing HR.

Clinical trial: esomeprazole for moderate-to-severe nighttime heartburn and gastro-oesophageal reflux disease-related sleep disturbances.

PubMed

Johnson, D; Crawley, J A; Hwang, C; Brown, K

2010-07-01

Nighttime heartburn, common among patients with gastro-oesophageal reflux disease (GERD), is associated with substantial clinical effects. GERD-related sleep disturbances are underappreciated and undertreated. To evaluate the efficacy of esomeprazole on GERD-related nighttime heartburn and associated sleep disturbances. In this multicentre, randomized, double-blind, placebo-controlled study, patients with moderate-to-severe nighttime heartburn and GERD-related sleep disturbances (endoscopies not required) received esomeprazole 20 mg or placebo each morning for 4 weeks. Heartburn symptoms and GERD-related sleep disturbances were evaluated using the validated Pittsburgh Sleep Quality Index and validated Work Productivity and Activity Impairment Questionnaire. The analysis included 262 patients (esomeprazole, n = 137; placebo, n = 125). Significantly more patients receiving esomeprazole achieved nighttime heartburn relief (primary end point) than those receiving placebo (34.3% vs. 10.4%; P < 0.0001). Secondary end points such as relief of GERD-related sleep disturbances (P = 0.006), days without GERD-related sleep disturbances (P = 0.0003) and complete resolution of sleep disturbances (P < 0.0001) favoured esomeprazole over placebo. Sleep quality, work productivity and regular daily activities also improved significantly with esomeprazole vs. placebo. Esomeprazole 20 mg is effective for patients with moderate-to-severe nighttime heartburn and GERD-related sleep disturbances, improving heartburn symptoms, sleep quality, work productivity and functionality.

Starting time for induction of labor and the risk for night-time delivery.

PubMed

Thorsell, M; Lyrenäs, S; Andolf, E; Kaijser, M

2011-08-01

To analyze if starting time for labor induction affected the risk of night-time delivery, and to evaluate to what extent the risk was influenced by Bishop score at start of induction, mode of induction, and parity. A retrospective cohort study of women who delivered at Danderyd Hospital, Stockholm, Sweden, 2002-2006, comprising 1940 women induced by Dinoprostone (PGE(2)) or transcervical balloon catheter (BARD). Risks for night-time delivery were calculated as absolute risk and Odds Ratios by unconditional logistic regression using induction of labor in the morning as reference. For nulliparae with Bishop score 0-3 induced by BARD, odds ratios for night-time delivery were 0.42 (95% C.I. 0.19-0.93) and 0.09 (95% C.I. 0.02-0.47) when inductions started in the afternoon and evening, respectively, compared to inductions starting in the morning For multiparae, however, the risk of night-time delivery was highest if induction started in the evening. Compared to inductions started in the morning, odds ratios for night-time delivery were 3.53 (95% C.I. 2.57-4.83) and 8.49 (95% C.I. 4.45-16.19) for induction starting in the afternoon and evening, respectively. Starting time of labor induction affects the risk of giving birth at night. For nulliparae induced by BARD, starting the induction in the evening instead of during the day may reduce the number of night-time deliveries substantially. For multiparae, however, our data suggest that induction of labor should take place in the morning. Copyright © 2011 Elsevier B.V. All rights reserved.

Prolonged Nightly Fasting and Breast Cancer Risk: Findings from NHANES (2009-2010).

PubMed

Marinac, Catherine R; Natarajan, Loki; Sears, Dorothy D; Gallo, Linda C; Hartman, Sheri J; Arredondo, Elva; Patterson, Ruth E

2015-05-01

A novel line of research has emerged, suggesting that daily feeding-fasting schedules that are synchronized with sleep-wake cycles have metabolic implications that are highly relevant to breast cancer. We examined associations of nighttime fasting duration with biomarkers of breast cancer risk among women in the 2009-2010 U.S. National Health and Nutrition Examination Survey. Dietary, anthropometric, and HbA1c data were available for 2,212 women, and 2-hour postprandial glucose concentrations were available for 1,066 women. Nighttime fasting duration was calculated using 24-hour food records. Separate linear regression models examined associations of nighttime fasting with HbA1c and 2-hour glucose concentrations. Logistic regression modeled associations of nighttime fasting with elevated HbA1c (HbA1c ≥ 39 mmol/mol or 5.7%) and elevated 2-hour glucose (glucose ≥ 140 mg/dL). All models adjusted for age, education, race/ethnicity, body mass index, total kcal intake, evening kcal intake, and the number of eating episodes per day. Each 3-hour increase in nighttime fasting (roughly 1 SD) was associated with a 4% lower 2-hour glucose measurement [β, 0.96; 95% confidence interval (CI), 0.93-1.00; P < 0.05], and a nonstatistically significant decrease in HbA1c. Logistic regression models indicate that each 3-hour increase in nighttime fasting duration was associated with roughly a 20% reduced odds of elevated HbA1c (OR, 0.81; 95% CI, 0.68-0.97; P < 0.05) and nonsignificantly reduced odds of elevated 2-hour glucose. A longer nighttime duration was significantly associated with improved glycemic regulation. Randomized trials are needed to confirm whether prolonged nighttime fasting could improve biomarkers of glucose control, thereby reducing breast cancer risk. ©2015 American Association for Cancer Research.

Association between Nighttime Sleep and Napping in Older Adults

PubMed Central

Goldman, Suzanne E.; Hall, Martica; Boudreau, Robert; Matthews, Karen A.; Cauley, Jane A.; Ancoli-Israel, Sonia; Stone, Katie L.; Rubin, Susan M.; Satterfield, Suzanne; Simonsick, Eleanor M.; Newman, Anne B.

2008-01-01

Study Objectives: Napping might indicate deficiencies in nighttime sleep, but the relationship is not well defined. We assessed the association of nighttime sleep duration and fragmentation with subsequent daytime sleep. Design: Cross-sectional study. Participants: 235 individuals (47.5% men, 29.7% black), age 80.1 (2.9) years. Measurements and Results: Nighttime and daytime sleep were measured with wrist actigraphy and sleep diaries for an average of 6.8 (SD 0.7) nights. Sleep parameters included total nighttime sleep (h), movement and fragmentation index (fragmentation), and total daytime sleep (h). The relationship of total nighttime sleep and fragmentation to napping (yes/no) was assessed using logistic regression. In individuals who napped, mixed random effects models were used to determine the association between the previous night sleep duration and fragmentation and nap duration, and nap duration and subsequent night sleep duration. All models were adjusted for age, race, gender, BMI, cognitive status, depression, cardiovascular disease, respiratory symptoms, diabetes, pain, fatigue, and sleep medication use. Naps were recorded in sleep diaries by 178 (75.7%) participants. The odds ratios (95% CI) for napping were higher for individuals with higher levels of nighttime fragmentation (2.1 [0.8, 5.7]), respiratory symptoms (2.4 [1.1, 5.4]), diabetes (6.1 [1.2, 30.7]), and pain (2.2 [1.0, 4.7]). Among nappers, neither sleep duration nor fragmentation the preceding night was associated with nap duration the next day. Conclusion: More sleep fragmentation was associated with higher odds of napping although not with nap duration. Further research is needed to determine the causal association between sleep fragmentation and daytime napping. Citation: Goldman SE; Hall M; Boudreau R; Matthews KA; Cauley JA; Ancoli-Israel S; Stone KL; Rubin SM; Satterfield S; Simonsick EM; Newman AB. Association between nighttime sleep and napping in older adults. SLEEP 2008;31(5):733-740. PMID:18517043

Intermediate Pause at Daytime Is Associated With Increased Cardiovascular Risk and Mortality: An 8-Year Cohort Study.

PubMed

Liu, Chih-Min; Lin, Chin-Yu; Chang, Shih-Lin; Lin, Yenn-Jiang; Lo, Li-Wei; Hu, Yu-Feng; Chao, Tze-Fan; Chung, Fa-Po; Tuan, Ta-Chuan; Liao, Jo-Nan; Chen, Yun-Yu; Te, Abigail Louise D; Yamada, Shinya; Kuo, Ling; Li, Hsing-Yuan; Chang, Ting-Yung; Minh, Hoang Quang; Salim, Simon; Ba, Vu Van; Vicera, Jennifer Jeanne B; Wu, Cheng-I; Chuang, Chieh-Mao; Huang, Ting-Chung; Hsieh, Yu-Cheng; Chen, Shih-Ann

2018-06-12

Long-term cardiovascular risk in patients with intermediate pauses remains unclear. Whether asymptomatic patients with intermediate pauses have increased future cardiovascular events remains unknown. We hypothesize that intermediate pause is associated with increased cardiovascular risk and mortality. We retrospectively analyzed 5291 patients who have pauses of <3 seconds on 24-hour Holter monitoring. Patients with pauses of 2 to 3 seconds constitute the intermediate pause patients, who are further divided into daytime pause (8:00 am-8:00 pm), nighttime pause (8:00 pm-8:00 am), and daytime plus nighttime pause groups depending on the occurring time of the pauses. The rest of the patients (pause <2 seconds) are the no pause group. The multivariate Cox hazards regression model was used to assess the hazard ratio for mortality (primary outcome) and adverse cardiovascular events (secondary outcome). There were 4859 (91.8%) patients in no pause, 248 (4.7%) in nighttime pause, 103 (1.9%) in daytime pause, and 81 (1.5%) in daytime plus nighttime pause groups. After a follow-up of 8.8±1.7 years' follow-up, 343 (6.5%) patients died. The risk for adverse cardiovascular events, including all-cause hospitalization, cardiovascular-cause hospitalization, pacemaker implantation, new-onset atrial fibrillation/heart failure, and transient ischemic attack, were higher in daytime pause and nighttime pause patients than those in the no pause group. Daytime pause (hazard ratio, 2.35; P =0.008) and daytime plus nighttime pause (hazard ratio, 2.26; P =0.016) patients have a higher mortality rate than that in nighttime pause. Patients with intermediate pause are associated with increased cardiovascular risk. Intermediate pauses occurring at daytime have a higher mortality rate than that at nighttime during long-term follow-up. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Stable Nighttime Light Decreased in Protected Area of California: Findings from DMSP-OLS Observations and the Importance for Protected Area Policy Making

NASA Astrophysics Data System (ADS)

Jia, S.; Gillespie, T. W.

2016-12-01

Stable nighttime light, an indicator of persisting human activity and light pollution is a well-recognized disturbance to the wilderness of protected areas (PAs). Mostly supported by in situ observations, very limited studies of light pollution for PAs focused at a regional level and on a continuous time span to support policy making effectively. DMSP-OLS stable nighttime series provide continuous observation of nightlight and have been widely applied in studies focusing on human activities. In this study, we employed inter-calibrated DMSP-OLS nightlight series from 1992 to 2012 to evaluate the change of intensity and extension of stable nighttime light inside California PAs. We observed a decrease of stable nighttime light and a shrinkage in spatial extent in PAs located in all ecoregions from 1992 to 2012, especially before 2004. Such decrease and shrinkage occurred mostly in southern California and the Bay Area where mega metropolitan clusters locate. The successful application of protecting strategies in PAs and the improved technologies of lighting may contribute to the relieving of light pollution in PAs. However, the stable nighttime light slightly increased since 2004, when there was limited room for stricter protective regulations and the pressure from population growth persisted. Population density explained most spatial distribution of nightlight in years with census tract level demographic data available, except PAs with the highest wilderness such as Sierra Nevada Mts. We anticipate to improve the models with the newest remote sensing nighttime product from NASA Suomi-NPP and annually updated demographic data from American Community Survey at census tract level in the future to provide a cost-effective evaluation on protecting strategies. Such evaluation will support land managers of PAs and local policy-makers for modification and proposal of policies.

Global satellite data highlights the diurnal asymmetry of the surface temperature response to deforestation

NASA Astrophysics Data System (ADS)

Schultz, Natalie M.; Lawrence, Peter J.; Lee, Xuhui

2017-04-01

Uncertainties remain about the spatial pattern and magnitude of the biophysical effects of deforestation. In particular, a diurnal asymmetry in the magnitude and sign of the surface temperature response to deforestation (ΔTS) has been observed, but the biophysical processes that contribute to day and nighttime ΔTS are not fully understood. In this study, we use a space-for-time approach with satellite and reanalysis data to investigate the biophysical processes that control the day and nighttime ΔTS. Additionally, we incorporate flux-tower data to examine two hypotheses for nighttime forest warming relative to open lands: (1) that forests generate turbulence in the stable nocturnal boundary layer, which brings heat aloft down to the surface, and (2) that forests store more heat during the day and release it at night. Our results confirm a diurnal asymmetry in ΔTS. Over most regions of the world, deforestation results in daytime warming and nighttime cooling. The strongest daytime warming is in the tropics, where the average ΔTS is 4.4 ± 0.07 K. The strongest nighttime cooling is observed in the boreal zone, where open lands are cooler than forests by an average of 1.4 ± 0.04 K. Daytime patterns of ΔTS are explained by differences in the latent heat flux (ΔLE) and absorbed solar radiation (ΔKa). We find that nighttime ΔTS is related to the strength of the nocturnal temperature inversion, with stronger temperature inversions at high latitudes and weak inversions in the tropics. Forest turbulence at night combined with stored heat release drives nighttime ΔTS patterns.

Association between light exposure at night and nighttime blood pressure in the elderly independent of nocturnal urinary melatonin excretion.

PubMed

Obayashi, Kenji; Saeki, Keigo; Iwamoto, Junko; Ikada, Yoshito; Kurumatani, Norio

2014-07-01

Circadian misalignment between internal and environmental rhythms dysregulates blood pressure (BP) variability because of disruption of the biological clock, resulting in increased nighttime BP. Although exposure to light-at-night is associated with the circadian misalignment, it remains unclear whether exposure to light-at-night in home settings is associated with nighttime BP. In this cross-sectional analysis of 528 elderly individuals (mean age: 72.8 years), we measured bedroom light intensity at 1-min intervals on two consecutive nights along with ambulatory BP, overnight urinary melatonin excretion and actigraphy. With regard to adjusted mean comparisons using analysis of covariance, the light-at-night group (average: ≥5 lux; n = 109) showed significantly higher nighttime systolic BP (SBP; adjusted mean: 120.8 vs. 116.5 mmHg, p = 0.01) and diastolic BP (70.1 vs. 67.1 mmHg, p < 0.01) compared with the Darker group (average: <5 lux; n = 419) independently of potential confounding factors including overnight urinary melatonin excretion and actigraphic sleep quality. We observed consistent associations between light-at-night and nighttime BP in different cutoff values for light-at-night intensity (i.e. 3 and 10 lux). In conclusion, exposure to light-at-night in home settings is significantly associated with increased nighttime BP in elderly individuals independently of overnight urinary melatonin excretion. A 4.3 mmHg increase in nighttime SBP is associated with a 6.1% increase in total mortality, which corresponds to approximately 10 000 annual excess deaths in Japanese elderly population.

Nighttime OClO in the Winter Arctic Vortex

NASA Technical Reports Server (NTRS)

Canty, T.; Riviere, E. D.; Salawitch, R. J.; Berthet, G.; Renard, J. -B.; Pfeilsticker, K.; Dorf, M.; Butz, A.; Bosch, H.; Stimpfle, R. M.;

Nighttime lower ionosphere height estimation from the VLF modal interference distance

NASA Astrophysics Data System (ADS)

Samanes, Jorge; Raulin, Jean-Pierre; Cao, Jinbin; Magalhães, Antonio

2018-01-01

We have studied the dynamics of the nighttime lower ionosphere height through continuous monitoring of the VLF modal interference distance (so-called distance D). Since the distance D is related to the nighttime propagation modes within the Earth-Ionosphere waveguide, it provides information of the nighttime reflection height (hN). We have used a long-term VLF narrowband database of almost 8 years (2006-2014) from a long transequatorial VLF propagation path between the transmitter NPM (Hawaii, 21.4 kHz) and the receiver ATI (Atibaia, Brazil). Our results show that hN assumes lower values during northern hemisphere wintertime as compared with summertime. By using the Lomb-Scargle periodogram, periodicities around 180 (SAO), 365 (AO) and 800 (QBO) days have been found, being the periodicity around 180 days stronger than all other oscillations. Since these large-scale oscillations are commonly observed in several measurable parameters of the mesosphere-lower thermosphere (MLT) region, our results suggest that the nighttime lower ionosphere can be strongly influenced by the dynamics of the MLT region. The effect of the long-term solar activity on hN is also studied, resulting in high negative correlation (R = -0.91). This effect makes hN decrease around 1.2 km from low to high solar activity. This result suggests a control of the solar radiation on the nighttime lower ionosphere, and hence, on the electron density at night.

Nutrient and water addition effects on day- and night-time conductance and transpiration in a C3 desert annual.

PubMed

Ludwig, Fulco; Jewitt, Rebecca A; Donovan, Lisa A

2006-06-01

Recent research has shown that many C3 plant species have significant stomatal opening and transpire water at night even in desert habitats. Day-time stomatal regulation is expected to maximize carbon gain and prevent runaway cavitation, but little is known about the effect of soil resource availability on night-time stomatal conductance (g) and transpiration (E). Water (low and high) and nutrients (low and high) were applied factorially during the growing season to naturally occurring seedlings of the annual Helianthus anomalus. Plant height and biomass were greatest in the treatment where both water and nutrients were added, confirming resource limitations in this habitat. Plants from all treatments showed significant night-time g (approximately 0.07 mol m(-2) s(-1)) and E (approximately 1.5 mol m(-2) s(-1)). In July, water and nutrient additions had few effects on day- or night-time gas exchange. In August, however, plants in the nutrient addition treatments had lower day-time photosynthesis, g and E, paralleled by lower night-time g and E. Lower predawn water potentials and higher integrated photosynthetic water-use efficiency suggests that the nutrient addition indirectly induced a mild water stress. Thus, soil resources can affect night-time g and E in a manner parallel to day-time, although additional factors may also be involved.

Night-time naturally ventilated offices: Statistical simulations of window-use patterns from field monitoring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yun, Geun Young; Steemers, Koen

2010-07-15

This paper investigates occupant behaviour of window-use in night-time naturally ventilated offices on the basis of a pilot field study, conducted during the summers of 2006 and 2007 in Cambridge, UK, and then demonstrates the effects of employing night-time ventilation on indoor thermal conditions using predictive models of occupant window-use. A longitudinal field study shows that occupants make good use of night-time natural ventilation strategies when provided with openings that allow secure ventilation, and that there is a noticeable time of day effect in window-use patterns (i.e. increased probability of action on arrival and departure). We develop logistic models ofmore » window-use for night-time naturally ventilated offices, which are subsequently applied to a behaviour algorithm, including Markov chains and Monte Carlo methods. The simulations using the behaviour algorithm demonstrate a good agreement with the observational data of window-use, and reveal how building design and occupant behaviour collectively affect the thermal performance of offices. They illustrate that the provision of secure ventilation leads to more frequent use of the window, and thus contributes significantly to the achievement of a comfortable indoor environment during the daytime occupied period. For example, the maximum temperature for a night-time ventilated office is found to be 3 C below the predicted value for a daytime-only ventilated office. (author)« less

Nighttime Aerosol Optical Depth Measurements Using a Ground-based Lunar Photometer

NASA Technical Reports Server (NTRS)

Berkoff, Tim; Omar, Ali; Haggard, Charles; Pippin, Margaret; Tasaddaq, Aasam; Stone, Tom; Rodriguez, Jon; Slutsker, Ilya; Eck, Tom; Holben, Brent;

Description of nighttime cough epochs in patients with stable COPD GOLD II-IV.

PubMed

Fischer, Patrick; Gross, Volker; Kroenig, Johannes; Weissflog, Andreas; Hildebrandt, Olaf; Sohrabi, Keywan; Koehler, Ulrich

Chronic cough is one of the main symptoms of COPD. Ambulatory objective monitoring provides novel insights into the determinants and characteristics of nighttime cough in COPD. Nighttime cough was monitored objectively by LEOSound lung sound monitor in patients with stable COPD II-IV. In 30 patients, with 10 patients in each stage group, nighttime cough was analyzed for epoch frequency, epoch severity (epoch length and coughs per epoch), and pattern (productive or nonproductive). Cough was found in all patients ranging from 1 to 294 events over the recording period. In 29 patients, cough epochs were monitored, ranging from 1 to 75 epochs. The highest amount of cough epochs was found in patients with COPD stage III. Active smokers had significantly more productive cough epochs (61%) than nonsmokers (24%). We found a high rate of nighttime cough epochs in patients with COPD, especially in those in stage III. Productive cough was predominantly found in patients with persistent smoking. LEOSound lung sound monitor offers a practical and valuable opportunity to evaluate cough objectively.

Comparison of glucose fluctuations between day- and night-time measured using a continuous glucose monitoring system in diabetic dogs.

PubMed

Mori, Akihiro; Kurishima, Miyuki; Oda, Hitomi; Saeki, Kaori; Arai, Toshiro; Sako, Toshinori

2013-01-31

Monitoring of blood glucose concentration is important to evaluate the diabetic status of dogs. Continuous glucose monitoring systems (CGMS) have been applied in veterinary medicine for glucose monitoring in diabetic dogs. The purpose of the study was to evaluate the daily glycemic profiles obtained with CGMS and compare glucose fluctuations between day- and night-time in diabetic dogs. Five diabetic dogs were used in this study and were treated with either NPH insulin or insulin detemir. For data analyses, day-time was defined as 9:00 am-9:00 pm and night-time as 9:00 pm-9:00 am. Using glucose profiles, we determined the mean glucose concentrations (1- and 12-hr intervals), and times spent in hyperglycemia >200 mg/dl or hypoglycemia <60 mg/dl. None of the parameters differed significantly between day-time and night-time in dogs treated with NPH insulin or insulin detemir. In conclusion, this study confirmed, using CGMS, that there are no differences in glucose fluctuations between day- and night-time, in diabetic dogs on a similar feeding regimen and insulin administration.

ALMA Thermal Observations of a Proposed Plume Source Region on Europa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trumbo, Samantha K.; Brown, Michael E.; Butler, Bryan J.

We present a daytime thermal image of Europa taken with the Atacama Large Millimeter Array. The imaged region includes the area northwest of Pwyll Crater, which is associated with a nighttime thermal excess seen by the Galileo Photopolarimeter Radiometer and with two potential plume detections. We develop a global thermal model of Europa and simulate both the daytime and nighttime thermal emission to determine if the nighttime thermal anomaly is caused by excess endogenic heat flow, as might be expected from a plume source region. We find that the nighttime and daytime brightness temperatures near Pwyll Crater cannot be matchedmore » by including excess heat flow at that location. Rather, we can successfully model both measurements by increasing the local thermal inertia of the surface.« less

Associations of Subjective Sleep Quality and Daytime Sleepiness With Cognitive Impairment in Adults and Elders With Heart Failure.

PubMed

Byun, Eeeseung; Kim, Jinyoung; Riegel, Barbara

2017-01-01

This study examined the association of subjective nighttime sleep quality and daytime sleepiness with cognitive impairment in 105 adults (< 60 years old) and 167 elders (≥ 60 years old) with heart failure. Nighttime sleep quality and daytime sleepiness were measured by the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale. Cognitive impairment was assessed using a neuropsychological battery measuring attention, memory, and processing speed. Multivariate logistic regression was used. In adults, daytime sleepiness was associated with cognitive impairment, whereas poor nighttime sleep quality was associated with cognitive impairment in elders. Age may play an important role in how sleep impacts cognition in persons with heart failure. Improving nighttime sleep quality and daytime sleepiness in this population may improve cognition.

The Student Telescope Network (STN) experiment

NASA Astrophysics Data System (ADS)

Hannahoe, Ryan M.; Stencel, Robert E.; Bisque, Steve; Rice, Mike

2003-02-01

Several factors make observational astronomy difficult for pre-college students and teachers. (1) not many schools have teachers trained to use and maintain astronomy equipment; (2) school usually happens during the day and observing normally is a night-time activity; (3) the scourge of light pollution has hidden the stars from many students living in or near cities; (4) there is a general lack of access to expertise when needed. In addition, physically disabled students cannot climb ladders, to access the telescope eyepiece. Internet access to computer-controlled telescopes equipped with digital cameras can solve many of these difficulties. This enables students and their teachers to access well-maintained, robust Internet-controllable telescopes in dark-site locations and to consult more readily with experts. We present the results of technical solutions to Internet-control of telescopes, by Software Bisque, the New Mexico Skies Guest Observatory and the Youth Activities Committee of the Astronomical League in collaboration with Denver University Astronomy. We jointly submitted a funding proposal to the Institute for Connecting Science Research to the Classroom, and conducted a pilot program allowing high school students to access a CCD-equipped, accurately-pointing and tracking telescope, controllable over the Web, with a user-friendly skymap browser tool. With suitably placed telescopes worldwide, observing from the classroom in daylight will become feasible, as we have demonstrated with Australian and Eurasian student users of the New Mexico Skies Internet telescope. We report here on a three-month pilot project exploring this solution, conducted Feb-May 2002. User interest proved phenomenal, while user statistics proved diverse and there were distinct lessons learned about how to enhance student participation in the research process. We thank the Institute for Connecting Science Research to the Classroom for a grant to the University of Denver in partial support of this effort, and acknowleedge in-kind support from the estate of William Herschel Womble. Details at website www.du.edu/~rstencel/stn.htm.

Association of napping and night-time sleep with impaired glucose regulation, insulin resistance and glycated haemoglobin in Chinese middle-aged adults with no diabetes: a cross-sectional study

PubMed Central

Baoying, Huang; Hongjie, Chen; Changsheng, Qiu; Peijian, Wu; Qingfei, Lin; Yinghua, Lin; Huibin, Huang; Jixing, Liang; Liantao, Li; Ling, Chen; Kaka, Tang; Zichun, Chen; Lixiang, Lin; Jieli, Lu; Yufang, Bi; Guang, Ning; Penli, Zhu; Junping, Wen; Gang, Chen

2014-01-01

Objective To assess associations between napping and night-time sleep duration with impaired glucose regulation, insulin resistance (IR) and glycated haemoglobin (HbA1c). Design Cross-sectional study. Setting Fujian Province, China, from June 2011 to January 2012. Participants This study enrolled 9028 participants aged 40–65 years. Data of 7568 participants with no diabetes were included for analysis. Type 2 diabetes was defined applying WHO criteria. Outcome measures Participants’ daytime napping and night-time sleep duration data were collected using a standardised self-reported Chinese-language questionnaire about sleep frequency and quality. Anthropometric and laboratory parameters were also measured. IR was defined as a HOMA-IR index value >2.50. ORs and 95% CIs were derived from multivariate logistic regression models. Results Participants (mean age 51.1±7.0 years) included 3060 males and 4508 females with average night-time sleep of 7.9 h. A higher proportion of males napped than females. After adjustment for potential confounders, ORs for HbA1c >6.0% were 1.28 and 1.26 for those napping ≤1 h and >1 h (p=0.002 and p=0.018), respectively. Statistically significant differences in IR between nappers and non-nappers were only marginal clinically. Odds for HbA1c >6.0% were significantly lower in participants with longer night-time sleep durations than in the reference group (>8 h vs 6–8 h). Odds for IR were significantly lower in participants whose night-time sleep hours deviated from the reference group (<6 h, >8 h vs 6–8 h) Conclusions Chinese middle-aged adults with no diabetes who napped had higher HbA1c and IR; those with shorter night-time sleep durations had increased HbA1c. Night-time sleep hours that are either <6 or >8 tend to be associated with lower odds for IR. Further studies are necessary to determine the underlying clinical significance and mechanisms behind these associations. PMID:25056969

Sleep duration, nap habits, and mortality in older persons.

PubMed

Cohen-Mansfield, Jiska; Perach, Rotem

2012-07-01

To examine the effect of nighttime sleep duration on mortality and the effect modification of daytime napping on the relationship between nighttime sleep duration and mortality in older persons. Prospective survey with 20-yr mortality follow-up. The Cross-Sectional and Longitudinal Aging Study, a multidimensional assessment of a stratified random sample of the older Jewish population in Israel conducted between 1989-1992. There were 1,166 self-respondent, community-dwelling participants age 75-94 yr (mean, 83.40, standard deviation, 5.30). Nighttime sleep duration, napping, functioning (activities of daily living, instrumental activities of daily living, Orientation Memory Concentration Test), health, and mortality. Duration of nighttime sleep of more than 9 hr was significantly related to increased mortality in comparison with sleeping 7-9 hr (hazard ratio [HR] = 1.31, P < 0.01) after adjusting for demographic, health, and function variables, whereas for short nighttime sleep of fewer than 7 hr mortality did not differ from that of 7-9 hr of sleep. For those who nap, sleeping more than 9 hr per night significantly increased mortality risk (HR = 1.385, P < 0.05) and shorter nighttime sleep reduced mortality significantly in the unadjusted model (HR = 0.71, P < 0.001) but only approached significance in the fully adjusted model (HR = 0.82, P = 0.054). For those who do not or sometimes nap, a short amount of sleep appears to be harmful up to age 84 yr and may be protective thereafter (HR = 1.51, confidence interval [CI] = 1.13-2.02, P < 0.01; HR = 0.76, CI = 0.49-1.17, in the fully adjusted model, respectively). The findings are novel in demonstrating the protective effect of short nighttime sleep duration in individuals who take daily naps and suggest that the examination of the effect of sleep needs to take into account sleep duration per 24 hr, rather than daytime napping or nighttime sleep per se. Cohen-Mansfield J; Perach R. Sleep duration, nap habits, and mortality in older persons. SLEEP 2012;35(7):1003-1009.

21 CFR 338.3 - Definition.

Code of Federal Regulations, 2013 CFR

2013-04-01

... NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE General Provisions § 338.3 Definition. As used in this part: Nighttime sleep-aid. A drug that is useful for the relief of occasional...

21 CFR 338.3 - Definition.

Code of Federal Regulations, 2010 CFR

2010-04-01

... NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE General Provisions § 338.3 Definition. As used in this part: Nighttime sleep-aid. A drug that is useful for the relief of occasional...

21 CFR 338.3 - Definition.

Code of Federal Regulations, 2012 CFR

2012-04-01

... NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE General Provisions § 338.3 Definition. As used in this part: Nighttime sleep-aid. A drug that is useful for the relief of occasional...

21 CFR 338.3 - Definition.

Code of Federal Regulations, 2011 CFR

2011-04-01

... NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE General Provisions § 338.3 Definition. As used in this part: Nighttime sleep-aid. A drug that is useful for the relief of occasional...

21 CFR 338.3 - Definition.

Code of Federal Regulations, 2014 CFR

2014-04-01

... NIGHTTIME SLEEP-AID DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE General Provisions § 338.3 Definition. As used in this part: Nighttime sleep-aid. A drug that is useful for the relief of occasional...

Gender differences in nighttime sleep and daytime napping as predictors of mortality in older adults: the Rancho Bernardo study.

PubMed

Jung, Kyu-In; Song, Chan-Hee; Ancoli-Israel, Sonia; Barrett-Connor, Elizabeth

2013-01-01

Many studies suggest optimal sleep duration for survival is 7-8h/night. We report the gender-specific independent association of all-cause mortality with nighttime sleep and daytime nap duration in older adults who were followed for up to 19years. Between 1984 and 1987, 2001 community-dwelling, mostly retired, adults (1112 women), age 60-96years, answered questions about health, mood, medications, life-style, daytime napping, and nighttime sleep duration. Vital status was confirmed for 96% through July 2001. At baseline, men reported significantly longer nighttime sleep and daytime napping than women. In both men and women, nighttime sleep <6h was associated with depressed mood and sleep-related medication, and ⩾9h was associated with more alcohol consumption. Napping ⩾30min was associated with prevalent depressed mood, coronary heart disease, and cancer. Of the group, 61% died over the next 19years, at an average age of 85.6years. Mortality risk was lowest among those sleeping 7-7.9h/night in both men and women. Multiple-adjusted analyses showed that increased mortality was associated with nighttime sleep ⩾9h in women (HR 1.51: 95% CI=1.05-2.18), and with daytime napping ⩾30min in men (HR 1.28: 95% CI, 1.00-1.64). Mechanisms for these differences are unknown. Copyright © 2012 Elsevier B.V. All rights reserved.

Arsia Mons by Day and Night

NASA Image and Video Library

2004-06-22

Released 22 June 2004 This pair of images shows part of Arsia Mons. Day/Night Infrared Pairs The image pairs presented focus on a single surface feature as seen in both the daytime and nighttime by the infrared THEMIS camera. The nighttime image (right) has been rotated 180 degrees to place north at the top. Infrared image interpretation Daytime: Infrared images taken during the daytime exhibit both the morphological and thermophysical properties of the surface of Mars. Morphologic details are visible due to the effect of sun-facing slopes receiving more energy than antisun-facing slopes. This creates a warm (bright) slope and cool (dark) slope appearance that mimics the light and shadows of a visible wavelength image. Thermophysical properties are seen in that dust heats up more quickly than rocks. Thus dusty areas are bright and rocky areas are dark. Nighttime: Infrared images taken during the nighttime exhibit only the thermophysical properties of the surface of Mars. The effect of sun-facing versus non-sun-facing energy dissipates quickly at night. Thermophysical effects dominate as different surfaces cool at different rates through the nighttime hours. Rocks cool slowly, and are therefore relatively bright at night (remember that rocks are dark during the day). Dust and other fine grained materials cool very quickly and are dark in nighttime infrared images. Image information: IR instrument. Latitude -19.6, Longitude 241.9 East (118.1 West). 100 meter/pixel resolution. http://photojournal.jpl.nasa.gov/catalog/PIA06399

Crater Ejecta by Day and Night

NASA Image and Video Library

2004-06-24

Released 24 June 2004 This pair of images shows a crater and its ejecta. Day/Night Infrared Pairs The image pairs presented focus on a single surface feature as seen in both the daytime and nighttime by the infrared THEMIS camera. The nighttime image (right) has been rotated 180 degrees to place north at the top. Infrared image interpretation Daytime: Infrared images taken during the daytime exhibit both the morphological and thermophysical properties of the surface of Mars. Morphologic details are visible due to the effect of sun-facing slopes receiving more energy than antisun-facing slopes. This creates a warm (bright) slope and cool (dark) slope appearance that mimics the light and shadows of a visible wavelength image. Thermophysical properties are seen in that dust heats up more quickly than rocks. Thus dusty areas are bright and rocky areas are dark. Nighttime: Infrared images taken during the nighttime exhibit only the thermophysical properties of the surface of Mars. The effect of sun-facing versus non-sun-facing energy dissipates quickly at night. Thermophysical effects dominate as different surfaces cool at different rates through the nighttime hours. Rocks cool slowly, and are therefore relatively bright at night (remember that rocks are dark during the day). Dust and other fine grained materials cool very quickly and are dark in nighttime infrared images. Image information: IR instrument. Latitude -9, Longitude 164.2 East (195.8 West). 100 meter/pixel resolution. http://photojournal.jpl.nasa.gov/catalog/PIA06445

Actigraphy-based sleep parameters during the reinstatement of methamphetamine self-administration in rhesus monkeys.

PubMed

Berro, Laís F; Andersen, Monica L; Tufik, Sergio; Howell, Leonard L

2016-04-01

The objective of this study was to investigate nighttime activity of nonhuman primates during extinction and cue- and drug-primed reinstatement of methamphetamine self-administration. Adult rhesus monkeys (Macaca mulatta; n = 5) self-administered methamphetamine (0.01 mg/kg/injection, i.v.) under a fixed-ratio 20 schedule of reinforcement. Saline infusions were then substituted for methamphetamine and stimulus light (drug-conditioned stimulus presented during drug self-administration) withheld until subjects reached extinction criteria. Drug- and cue-induced reinstatement effects were evaluated after i.v. noncontingent priming injections of methamphetamine (0.03, 0.1, or 0.3 mg/kg). Activity-based sleep measures were evaluated with Actiwatch monitors a week before (baseline nighttime activity parameters) and throughout the protocol. Although methamphetamine self-administration did not significantly affect nighttime activity compared to baseline, sleeplike parameters were improved during extinction compared to self-administration maintenance. Priming injection of 0.1 mg/kg methamphetamine, but not 0.03 or 0.3 mg/kg, induced significant reinstatement effects. These behavioral responses were accompanied by nighttime outcomes, with increased sleep fragmentation and decreased sleep efficiency in the night following 0.1 mg/kg methamphetamine-induced reinstatement. In the absence of both drug and drug-paired cues (extinction conditions), nighttime activity decreased compared to self-administration maintenance. Additionally, effective reinstatement conditions impaired sleeplike measures. Our data indicate that the reintroduction of the stimulus light as a drug-paired cue increased nighttime activity. (c) 2016 APA, all rights reserved).

Observations and Modeling of the Nighttime Electron Density Enhancement in the Mid-latitude Ionosphere

NASA Astrophysics Data System (ADS)

Chen, C.; Saito, A.; Lin, C.; Huba, J. D.; Liu, J. G.

2010-12-01

In this study, we compare the observational data from FORMOSAT-3/COSMIC and theoretical model results performed by SAMI2 (Sami2 is Another Model of the Ionosphere) for studying the longitudinal structure of the Mid-latitude Summer Nighttime Anomaly (MSNA). In order to study the occurrence of the nighttime electron density enhancement, we defined MSNA index by the ratio of the difference of the nighttime and daytime electron densities. The observational results by the FORMOSAT-3/COSMIC satellites show that there are three obvious nighttime electron density enhancement areas around South American, European, and Northeast Asian regions during local summer. The SAMI2 model can also successfully reproduce the ionospheric MSNA structure during local summer on both hemispheres, except for Northeast Asian region. This difference between observation and model simulation may be caused by the difference between the neutral wind model and the real winds. The physical mechanisms for the longitudinal structure of the MSNA are investigated in the different model conditions. Results show that the equatorward meridional neutral winds can drive the electron density up to a higher altitude along the magnetic field lines and the longer plasma production rate by solar EUV at higher latitudes in the summer time can provide the electron density source in the nighttime ionosphere. We concluded that the combination effect by the neutral wind and the plasma production rate play the important role of the MSNA longitudinal structure.

Estimating groundwater evapotranspiration by a subtropical pine plantation using diurnal water table fluctuations: Implications from night-time water use

NASA Astrophysics Data System (ADS)

Fan, Junliang; Ostergaard, Kasper T.; Guyot, Adrien; Fujiwara, Stephen; Lockington, David A.

2016-11-01

Exotic pine plantations have replaced large areas of the native forests for timber production in the subtropical coastal Australia. To evaluate potential impacts of changes in vegetation on local groundwater discharge, we estimated groundwater evapotranspiration (ETg) by the pine plantation using diurnal water table fluctuations for the dry season of 2012 from August 1st to December 31st. The modified White method was used to estimate the ETg, considering the night-time water use by pine trees (Tn). Depth-dependent specific yields were also determined both experimentally and numerically for estimation of ETg. Night-time water use by pine trees was comprehensively investigated using a combination of groundwater level, sap flow, tree growth, specific yield, soil matric potential and climatic variables measurements. Results reveal a constant average transpiration flux of 0.02 mm h-1 at the plot scale from 23:00 to 05:00 during the study period, which verified the presence of night-time water use. The total ETg for the period investigated was 259.0 mm with an accumulated Tn of 64.5 mm, resulting in an error of 25% on accumulated evapotranspiration from the groundwater if night-time water use was neglected. The results indicate that the development of commercial pine plantations may result in groundwater losses in these areas. It is also recommended that any future application of diurnal water table fluctuation based methods investigate the validity of the zero night-time water use assumption prior to use.

Tree Species with Photosynthetic Stems Have Greater Nighttime Sap Flux.

PubMed

Chen, Xia; Gao, Jianguo; Zhao, Ping; McCarthy, Heather R; Zhu, Liwei; Ni, Guangyan; Ouyang, Lei

2018-01-01

An increasing body of evidence has shown that nighttime sap flux occurs in most plants, but the physiological implications and regulatory mechanism are poorly known. The significance of corticular photosynthesis has received much attention during the last decade, however, the knowledge of the relationship between corticular photosynthesis and nocturnal stem sap flow is limited at present. In this study, we divided seven tree species into two groups according to different photosynthetic capabilities: trees of species with ( Castanopsis hystrix, Michelia macclurei, Eucalyptus citriodora , and Eucalyptus grandis × urophylla ) and without ( Castanopsis fissa, Schima superba , and Acacia auriculiformis ) photosynthetic stems, and the sap flux ( J s ) and chlorophyll fluorescence parameters for these species were measured. One-way ANOVA analysis showed that the F v / F m (Maximum photochemical quantum yield of PSII) and Φ PSII (effective photochemical quantum yield of PSII) values were lower in non-photosynthetic stem species compared to photosynthetic stem species. The linear regression analysis showed that J s,d (daytime sap flux) and J s,n (nighttime sap flux) of non-photosynthetic stem species was 87.7 and 60.9% of the stem photosynthetic species. Furthermore, for a given daytime transpiration water loss, total nighttime sap flux was higher in species with photosynthetic stems (Slope SMA = 2.680) than in non-photosynthetic stems species (Slope SMA = 1.943). These results mean that stem corticular photosynthesis has a possible effect on the nighttime water flow, highlighting the important eco-physiological relationship between nighttime sap flux and corticular photosynthesis.

Tree Species with Photosynthetic Stems Have Greater Nighttime Sap Flux

PubMed Central

Chen, Xia; Gao, Jianguo; Zhao, Ping; McCarthy, Heather R.; Zhu, Liwei; Ni, Guangyan; Ouyang, Lei

2018-01-01

An increasing body of evidence has shown that nighttime sap flux occurs in most plants, but the physiological implications and regulatory mechanism are poorly known. The significance of corticular photosynthesis has received much attention during the last decade, however, the knowledge of the relationship between corticular photosynthesis and nocturnal stem sap flow is limited at present. In this study, we divided seven tree species into two groups according to different photosynthetic capabilities: trees of species with (Castanopsis hystrix, Michelia macclurei, Eucalyptus citriodora, and Eucalyptus grandis × urophylla) and without (Castanopsis fissa, Schima superba, and Acacia auriculiformis) photosynthetic stems, and the sap flux (Js) and chlorophyll fluorescence parameters for these species were measured. One-way ANOVA analysis showed that the Fv/Fm (Maximum photochemical quantum yield of PSII) and ΦPSII (effective photochemical quantum yield of PSII) values were lower in non-photosynthetic stem species compared to photosynthetic stem species. The linear regression analysis showed that Js,d (daytime sap flux) and Js,n (nighttime sap flux) of non-photosynthetic stem species was 87.7 and 60.9% of the stem photosynthetic species. Furthermore, for a given daytime transpiration water loss, total nighttime sap flux was higher in species with photosynthetic stems (SlopeSMA = 2.680) than in non-photosynthetic stems species (SlopeSMA = 1.943). These results mean that stem corticular photosynthesis has a possible effect on the nighttime water flow, highlighting the important eco-physiological relationship between nighttime sap flux and corticular photosynthesis. PMID:29416547

Columnar Aerosol Properties from Sun-and-star Photometry: Statistical Comparisons and Day-to-night Dynamic

NASA Technical Reports Server (NTRS)

Ramirez, Daniel Perez; Lyamani, H.; Olmo, F. J.; Whiteman, D. N.; Alados-Arboledas, L.

2012-01-01

This work presents the first analysis of longterm correlative day-to-night columnar aerosol optical properties. The aim is to better understand columnar aerosol dynamic from ground-based observations, which are poorly studied until now. To this end we have used a combination of sun-and-star photometry measurements acquired in the city of Granada (37.16 N, 3.60 W, 680 ma.s.l.; South-East of Spain) from 2007 to 2010. For the whole study period, mean aerosol optical depth (AOD) around 440 nm (+/-standard deviation) is 0.18 +/- 0.10 and 0.19 +/- 0.11 for daytime and nighttime, respectively, while the mean Angstr¨om exponent (alpha ) is 1.0 +/- 0.4 and 0.9 +/- 0.4 for daytime and nighttime. The ANOVA statistical tests reveal that there are no significant differences between AOD and obtained at daytime and those at nighttime. Additionally, the mean daytime values of AOD and obtained during this study period are coherent with the values obtained in the surrounding AERONET stations. On the other hand, AOD around 440 nm present evident seasonal patterns characterised by large values in summer (mean value of 0.20 +/- 0.10 both at daytime and nighttime) and low values in winter (mean value of 0.15 +/- 0.09 at daytime and 0.17 +/- 0.10 at nighttime). The Angstr¨om exponents also present seasonal patterns, but with low values in summer (mean values of 0.8 +/- 0.4 and 0.9 +/- 0.4 at dayand night-time) and relatively large values in winter (mean values of 1.2 +/- 0.4 and 1.0 +/- 0.3 at daytime and nighttime). These seasonal patterns are explained by the differences in the meteorological conditions and by the differences in the strength of the aerosol sources. To take more insight about the changes in aerosol particles between day and night, the spectral differences of the Angstrom exponent as function of the Angstr¨om exponent are also studied. These analyses reveal increases of the fine mode radius and of the fine mode contribution to AOD during nighttime, being more remarkable in the summer seasons. These variations are explained by the changes of the local aerosol sources and by the meteorological conditions between daytime and nighttime, as well as aerosol aging processes. Case studies during summer and winter for different aerosol loads and types are also presented to clearly illustrate these findings.

[Pathological nighttime fears in children: Clinical specificities and effective therapeutics].

PubMed

Ducasse, D; Denis, H

2015-09-01

Pathological nighttime fears in children have been little studied. However, this disorder is commonly encountered in medical consultations and is discomforting and dysfunctional for both the child and the family. Most nighttime fears are part and parcel of normal development, and emanate from increasingly sophisticated cognitive development in the growing child. Thus, most children report a variety of coping strategies generally helpful in reducing their anxiety, which resolves spontaneously in the growing child. Nevertheless, in about 10% of children, nighttime fears are related to one or more anxiety disorders according to Diagnostic and Statistical Manual of Mental Disorders criteria. Then, it is estimated that severe nighttime fears and sleep problems occur in 20-30% of children. This problem is not transient and has to be treated. This study aims to review clinical features of nighttime fears and possible treatments for these patients and their families. This systematic review follows the preferred reporting items for systematic reviews and meta-analysis (PRISMA) statement guidelines. Two databases (Medline and Web of Science) were searched combining the search terms: nighttime fears AND children. English and French languages were imposed. There were no publication date or publication status limitations. Pathological nighttime fears are responsible for emotional (crying, panic, tantrums at bedtime, loss of confidence, self-disparaging negative statements, and feeling of social embarrassment) and behavioral (wandering alone in the house at night, calls for parental or sibling comfort, bed sharing with parents or siblings, light source at night, refusal to go to the toilet alone at night) disturbances. This leads to a poor quality of sleep interfering with school learning, and also affects social development and family functioning. A full assessment has to be made to eliminate organic causes, have a baseline functioning, and search for comorbid anxiety diseases. The treatments which have proved effective are some cognitive-behavioral techniques: systematic desensitization (with relaxation or emotive imagery), reinforcement (gain of points and techniques of self statement), and cognitive techniques (reinforcing self-statements, reducing the aversive aspects of being in the dark, involving reality-testing statements, and active control are preferred in children older than 6 years, whereas the "anti-monster letter" and the techniques using a doll are preferred in children under 6 years old). The modelling technique seems to be appropriate at any age. We have explained the clinical features of pathological nighttime fears and the way to assess this disease, and we have pointed out the treatments whose effectiveness has been evaluated in this indication. Copyright © 2014 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

Determination of vehicle density from traffic images at day and nighttime

NASA Astrophysics Data System (ADS)

Mehrübeoğlu, Mehrübe; McLauchlan, Lifford

2007-02-01

In this paper we extend our previous work to address vehicle differentiation in traffic density computations1. The main goal of this work is to create vehicle density history for given roads under different weather or light conditions and at different times of the day. Vehicle differentiation is important to account for connected or otherwise long vehicles, such as trucks or tankers, which lead to over-counting with the original algorithm. Average vehicle size in pixels, given the magnification within the field of view for a particular camera, is used to separate regular cars and long vehicles. A separate algorithm and procedure have been developed to determine traffic density after dark when the vehicle headlights are turned on. Nighttime vehicle recognition utilizes blob analysis based on head/taillight images. The high intensity of vehicle lights are identified in binary images for nighttime vehicle detection. The stationary traffic image frames are downloaded from the internet as they are updated. The procedures are implemented in MATLAB. The results of both nighttime traffic density and daytime long vehicle identification algorithms are described in this paper. The determination of nighttime traffic density, and identification of long vehicles at daytime are improvements over the original work1.

Impact of nighttime paving operations on asphalt roughness behavior.

DOT National Transportation Integrated Search

2013-05-01

The relationship between nighttime construction scheduling and future road quality in terms of roughness was investigated. Research was three-phased: interviews with local leaders in paving, on-site observations, and historical data analyses. Intervi...

Night-time road construction operations synthesis of practice.

DOT National Transportation Integrated Search

2008-05-01

report synthesizes existing literature on nighttime construction operations, identifies gaps in the current state of knowledge, and summarizes research in progress studies that are planned or underway. The literature review and synthesis found the fo...

Research notes : nighttime illumination of work zone flaggers.

DOT National Transportation Integrated Search

2006-05-01

As daytime traffic demands increase, nighttime construction and maintenance work is becoming more prevalent. The effective and efficient illumination of flaggers in these work zones is a significant concern . Insufficient light levels, disabling glar...

Evaluation of the Washington nighttime seat belt enforcement program.

DOT National Transportation Integrated Search

2017-04-01

The Washington Traffic Safety Commission (WTSC) and the National Highway Traffic Safety Administration (NHTSA) : conducted a high-visibility Nighttime Seat Belt Enforcement (NTSBE) program in Washington. The two-year program : followed the basic Clic...

System and method for pre-cooling of buildings

DOEpatents

Springer, David A.; Rainer, Leo I.

2011-08-09

A method for nighttime pre-cooling of a building comprising inputting one or more user settings, lowering the indoor temperature reading of the building during nighttime by operating an outside air ventilation system followed, if necessary, by a vapor compression cooling system. The method provides for nighttime pre-cooling of a building that maintains indoor temperatures within a comfort range based on the user input settings, calculated operational settings, and predictions of indoor and outdoor temperature trends for a future period of time such as the next day.

Symptoms of Aerophagia Are Common in Patients on Continuous Positive Airway Pressure Therapy and Are Related to the Presence of Nighttime Gastroesophageal Reflux

PubMed Central

Shepherd, Kelly; Hillman, David; Eastwood, Peter

2013-01-01

Study Objectives: Continuous positive airway pressure (CPAP), the mainstay treatment for obstructive sleep apnea (OSA), involves administration of air under pressure to the upper airway. A well-known but poorly understood side effect of positive airway pressure therapies is aerophagia, air entering the esophagus and stomach rather than the lungs. Gastric distension, a consequence of aerophagia, can increase gastroesophageal reflux (GER) by increasing transient lower esophageal sphincter relaxations, the most common cause of reflux. This study aimed to determine: (i) the prevalence of aerophagia symptoms in a group of OSA patients on CPAP therapy, and (ii) whether aerophagia symptoms are related to an increase in prevalence of GER symptoms. Methods: Consecutive OSA patients undergoing polysomnography for the purpose of optimizing their CPAP therapy completed a validated questionnaire regarding GER symptoms and aerophagia symptoms. Complete datasets were collected for 259 individuals (203 males). Results: The group with aerophagia symptoms (n = 130) had a greater prevalence of frequent (≥ once a week) GER symptoms (29% vs. 10%, p < 0.05) and nighttime GER symptoms (9 vs. 2%, p < 0.05) than those without aerophagia (n = 129). The group with nighttime GER symptoms (n = 27) had a greater prevalence of aerophagia symptoms (63% vs. 23%, p < 0.05) than those without nighttime GER symptoms (n = 232). Conclusions: In patients with OSA being treated with CPAP, the prevalence of GER and nighttime GER symptoms is greater in those with symptoms of aerophagia than those without. CPAP-induced aerophagia might precipitate GER, particularly nighttime GER, by exacerbating transient lower esophageal relaxations through gastric distension. Commentary: A commentary on this article appears in this issue on page 19. Citation: Shepherd K; Hillman D; Eastwood P. Symptoms of aerophagia are common in patients on continuous positive airway pressure therapy and are related to the presence of nighttime gastroesophageal reflux. J Clin Sleep Med 2013;9(1):13-17. PMID:23319899

Nighttime Insomnia Symptoms and Perceived Health in the America Insomnia Survey (AIS)

PubMed Central

Walsh, James K.; Coulouvrat, Catherine; Hajak, Goeran; Lakoma, Matthew D.; Petukhova, Maria; Roth, Thomas; Sampson, Nancy A.; Shahly, Victoria; Shillington, Alicia; Stephenson, Judith J.; Kessler, Ronald C.

2011-01-01

Study Objectives: To explore the distribution of the 4 cardinal nighttime symptoms of insomnia—difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), early morning awakening (EMA), and nonrestorative sleep (NRS)—in a national sample of health plan members and the associations of these nighttime symptoms with sociodemographics, comorbidity, and perceived health. Design/Setting/Participants: Cross-sectional telephone survey of 6,791 adult respondents. Intervention: None. Measurements/Results: Current insomnia was assessed using the Brief Insomnia Questionnaire (BIQ)—a fully structured validated scale generating diagnoses of insomnia using DSM-IV-TR, ICD-10, and RDC/ICSD-2 inclusion criteria. DMS (61.0%) and EMA (52.2%) were more prevalent than DIS (37.7%) and NRS (25.2%) among respondents with insomnia. Sociodemographic correlates varied significantly across the 4 symptoms. All 4 nighttime symptoms were significantly related to a wide range of comorbid physical and mental conditions. All 4 also significantly predicted decrements in perceived health both in the total sample and among respondents with insomnia after adjusting for comorbid physical and mental conditions. Joint associations of the 4 symptoms predicting perceived health were additive and related to daytime distress/impairment. Individual-level associations were strongest for NRS. At the societal level, though, where both prevalence and strength of individual-level associations were taken into consideration, DMS had the strongest associations. Conclusions: The extent to which nighttime insomnia symptoms are stable over time requires future long-term longitudinal study. Within the context of this limitation, the results suggest that core nighttime symptoms are associated with different patterns of risk and perceived health and that symptom-based subtyping might have value. Citation: Walsh JK; Coulouvrat C; Hajak G; Lakoma MD; Petukhova M; Roth T; Sampson NA; Shahly V; Shillington A; Stephenson JJ; Kessler RC. Nighttime insomnia symptoms and perceived health in the America Insomnia Survey (AIS). SLEEP 2011;34(8):997-1011. PMID:21804662

Artificial light at night alters trophic interactions of intertidal invertebrates.

PubMed

Underwood, Charlotte N; Davies, Thomas W; Queirós, Ana M

2017-07-01

Despite being globally widespread in coastal regions, the impacts of light pollution on intertidal ecosystems has received little attention. Intertidal species exhibit many night-time-dependent ecological strategies, including feeding, reproduction, orientation and predator avoidance, which are likely negatively affected by shifting light regimes, as has been observed in terrestrial and aquatic taxa. Coastal lighting may shape intertidal communities through its influence on the nocturnal foraging activity of dogwhelks (Nucella lapillus), a widespread predatory mollusc that structures biodiversity in temperate rocky shores. In the laboratory, we investigated whether the basal and foraging activity of this predator was affected by exposure to night-time lighting both in the presence and absence of olfactory predator cues (Carcinus maenas, common shore crab). Assessments of dogwhelks' behavioural responses to night-time white LED lighting were performed on individuals that had been acclimated to night-time white LED lighting conditions for 16 days and individuals that had not previously been exposed to artificial light at night. Dogwhelks acclimated to night-time lighting exhibited natural refuge-seeking behaviour less often compared to control animals, but were more likely to respond to and handle prey irrespective of whether olfactory predator cues were present. These responses suggest night-time lighting likely increased the energetic demand of dogwhelks through stress, encouraging foraging whenever food was available, regardless of potential danger. Contrastingly, whelks not acclimated under night-time lighting were more likely to respond to the presence of prey under artificial light at night when olfactory predator cues were present, indicating an opportunistic shift towards the use of visual instead of olfactory cues in risk evaluation. These results demonstrate that artificial night-time lighting influences the behaviour of intertidal fauna such that the balance of interspecific interactions involved in community structuring may be affected. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

Setting Thresholds to Varying Blood Pressure Monitoring Intervals Differentially Affects Risk Estimates Associated With White-Coat and Masked Hypertension in the Population

PubMed Central

Asayama, Kei; Thijs, Lutgarde; Li, Yan; Gu, Yu-Mei; Hara, Azusa; Liu, Yan-Ping; Zhang, Zhenyu; Wei, Fang-Fei; Lujambio, Inés; Mena, Luis J.; Boggia, José; Hansen, Tine W.; Björklund-Bodegård, Kristina; Nomura, Kyoko; Ohkubo, Takayoshi; Jeppesen, Jørgen; Torp-Pedersen, Christian; Dolan, Eamon; Stolarz-Skrzypek, Katarzyna; Malyutina, Sofia; Casiglia, Edoardo; Nikitin, Yuri; Lind, Lars; Luzardo, Leonella; Kawecka-Jaszcz, Kalina; Sandoya, Edgardo; Filipovský, Jan; Maestre, Gladys E.; Wang, Jiguang; Imai, Yutaka; Franklin, Stanley S.; O’Brien, Eoin; Staessen, Jan A.

2015-01-01

Outcome-driven recommendations about time intervals during which ambulatory blood pressure should be measured to diagnose white-coat or masked hypertension are lacking. We cross-classified 8237 untreated participants (mean age, 50.7 years; 48.4% women) enrolled in 12 population studies, using ≥140/≥90, ≥130/≥80, ≥135/≥85, and ≥120/≥70 mm Hg as hypertension thresholds for conventional, 24-hour, daytime, and nighttime blood pressure. White-coat hypertension was hypertension on conventional measurement with ambulatory normotension, the opposite condition being masked hypertension. Intervals used for classification of participants were daytime, nighttime, and 24 hours, first considered separately, and next combined as 24 hours plus daytime or plus nighttime, or plus both. Depending on time intervals chosen, white-coat and masked hypertension frequencies ranged from 6.3% to 12.5% and from 9.7% to 19.6%, respectively. During 91 046 person-years, 729 participants experienced a cardiovascular event. In multivariable analyses with normotension during all intervals of the day as reference, hazard ratios associated with white-coat hypertension progressively weakened considering daytime only (1.38; P=0.033), nighttime only (1.43; P=0.0074), 24 hours only (1.21; P=0.20), 24 hours plus daytime (1.24; P=0.18), 24 hours plus nighttime (1.15; P=0.39), and 24 hours plus daytime and nighttime (1.16; P=0.41). The hazard ratios comparing masked hypertension with normotension were all significant (P<0.0001), ranging from 1.76 to 2.03. In conclusion, identification of truly low-risk white-coat hypertension requires setting thresholds simultaneously to 24 hours, daytime, and nighttime blood pressure. Although any time interval suffices to diagnose masked hypertension, as proposed in current guidelines, full 24-hour recordings remain standard in clinical practice. PMID:25135185

Simulation of Longwave Enhancement beneath Montane and Boreal Forests in CLM4.5

NASA Astrophysics Data System (ADS)

Todt, M.; Rutter, N.; Fletcher, C. G.; Wake, L. M.; Loranty, M. M.

2017-12-01

CMIP5 models have been shown to underestimate both trend and variability in northern hemisphere spring snow cover extent. A substantial fraction of this area is covered by boreal forests, in which the snow energy balance is dominated by radiation. Forest coverage impacts the surface radiation budget by shading the ground and enhancing longwave radiation. Longwave enhancement in boreal forests is a potential mechanism that contributes to uncertainty in snowmelt modelling, however, its impact on snowmelt in global land models has not been analysed yet. This study assesses the simulation of sub-canopy longwave radiation and longwave enhancement by CLM4.5, the land component of the NCAR Community Earth System Model, in which boreal forests are represented by three plant functional types (PFT): evergreen needleleaf trees (ENT), deciduous needleleaf trees (DNT), and deciduous broadleaf trees (DBT). Simulation of sub-canopy longwave enhancement is evaluated at boreal forest sites covering the three boreal PFT in CLM4.5 to assess the dependence of simulation errors on meteorological forcing, vegetation type and vegetation density. ENT are evaluated over a total of six snowmelt seasons in Swiss alpine and subalpine forests, as well as a single season at a Finnish arctic site with varying vegetation density. A Swedish artic site features varying vegetation density for DBT for a single winter, and two sites in Eastern Siberia are included covering a total of four snowmelt seasons in DNT forests. CLM4.5 overestimates the diurnal range of sub-canopy longwave radiation and consequently longwave enhancement, overestimating daytime values and underestimating nighttime values. Simulation errors result mainly from clear sky conditions, due to high absorption of shortwave radiation during daytime and radiative cooling during nighttime. Using recent improvements to the canopy parameterisations of SNOWPACK as a guideline, CLM4.5 simulations of sub-canopy longwave radiation improved through the implementation of a heat mass parameterisation, i.e. including thermal inertia due to biomass. However, this improvement does not substantially reduce the amplitude of the diurnal cycle, a result also found during the development of SNOWPACK.

The role of deep convection and nocturnal low-level jets for dust emission in summertime West Africa: Estimates from convection-permitting simulations

PubMed Central

Heinold, B; Knippertz, P; Marsham, JH; Fiedler, S; Dixon, NS; Schepanski, K; Laurent, B; Tegen, I

2013-01-01

[1] Convective cold pools and the breakdown of nocturnal low-level jets (NLLJs) are key meteorological drivers of dust emission over summertime West Africa, the world’s largest dust source. This study is the first to quantify their relative contributions and physical interrelations using objective detection algorithms and an off-line dust emission model applied to convection-permitting simulations from the Met Office Unified Model. The study period covers 25 July to 02 September 2006. All estimates may therefore vary on an interannual basis. The main conclusions are as follows: (a) approximately 40% of the dust emissions are from NLLJs, 40% from cold pools, and 20% from unidentified processes (dry convection, land-sea and mountain circulations); (b) more than half of the cold-pool emissions are linked to a newly identified mechanism where aged cold pools form a jet above the nocturnal stable layer; (c) 50% of the dust emissions occur from 1500 to 0200 LT with a minimum around sunrise and after midday, and 60% of the morning-to-noon emissions occur under clear skies, but only 10% of the afternoon-to-nighttime emissions, suggesting large biases in satellite retrievals; (d) considering precipitation and soil moisture effects, cold-pool emissions are reduced by 15%; and (e) models with parameterized convection show substantially less cold-pool emissions but have larger NLLJ contributions. The results are much more sensitive to whether convection is parameterized or explicit than to the choice of the land-surface characterization, which generally is a large source of uncertainty. This study demonstrates the need of realistically representing moist convection and stable nighttime conditions for dust modeling. Citation: Heinold, B., P. Knippertz, J. H. Marsham, S. Fiedler, N. S. Dixon, K. Schepanski, B. Laurent, and I. Tegen (2013), The role of deep convection and nocturnal low-level jets for dust emission in summertime West Africa: Estimates from convection-permitting simulations, J. Geophys. Res. Atmos., 118, 4385–4400, doi:10.1002/jgrd.50402. PMID:25893153

Auroral omens of the American Civil War

USGS Publications Warehouse

Love, Jeffrey J.

2014-01-01

Aurorae are a splendid night-time sight: coruscations of green, purple, and red fluorescent light in the form of gently wafting ribbons, billowing curtains, and flashing rays. Mostly seen at high latitudes, in the north aurorae are often called the northern lights or aurora borealis, and, in the south, the southern lights or aurora australis. The mystery of their cause has historically been the subject of wonder. The folklore and mythology of some far-northern civilizations attributed auroral light to celestial deities. And, in ironic contrast with their heavenly beauty, unusual auroral displays, such as those seen on rare occasions at lower southern latitudes, have sometimes been interpreted as portending unfavorable future events. Today we understand aurorae to be a visual manifestation of the dynamic conditions in the space environment surrounding the earth. Important direct evidence in support of this theory came on September 1, 1859. On that day, an English astronomer named Richard Carrington was situated at his telescope, which was pointed at the sun. While observing and sketching a large group of sunspots, he saw a solar flare—intense patches of white light that were superimposed upon the darker sunspot group and which were illuminated for about a minute. One day later, a magnetic storm was recorded at specially designed observatories in Europe, across Russia, and in India. By many measures, the amplitude of magnetic disturbance was the greatest ever recorded. In the United States, the effects of the Carrington storm could be seen as irregular backand-forth deflections of a few degrees in the magnetized needle of a compass. Rapid magnetic variation also induced electric fields in the earth’s conducting lithosphere, and interfered with the operation of telegraph systems. The Carrington magnetic storm, and an earlier storm that had occurred on August 28, 1859, caused spectacular displays of aurora borealis in the night-time sky over the entire United States and the western hemisphere, possibly all the way down to the equator. This was extremely unusual, so much so that an auroral event o

Mobile luminance data collection system user manual.

DOT National Transportation Integrated Search

2013-04-01

While nighttime driving volumes are lower than daytime, the percentage of crashes with respect to volume is higher, so it is critical that transportation agencies do everything economically possible to improve nighttime driving safety. One crucial pa...

Maternal depressive symptoms, dysfunctional cognitions, and infant night waking: the role of maternal nighttime behavior.

PubMed

Teti, Douglas M; Crosby, Brian

2012-01-01

Mechanisms were examined to clarify relations between maternal depressive symptoms, dysfunctional cognitions, and infant night waking among 45 infants (1-24 months) and their mothers. A mother-driven mediational model was tested in which maternal depressive symptoms and dysfunctional cognitions about infant sleep predicted infant night waking via their impact on mothers' bedtime and nighttime behavior with infants (from video). Two infant-driven mediational models were also examined, in which infant night waking predicted maternal depressive symptoms, or dysfunctional cognitions, via their impact on nighttime maternal behavior. Stronger support for the mother-driven model was obtained, which was further supported by qualitative observations from video-recordings. This study provides important insights about maternal depression's effects on nighttime parenting, and how such parenting affects infant sleep. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

Daytime and nighttime wind differentially affects hydraulic properties and thigmomorphogenic response of poplar saplings.

PubMed

Huang, Ping; Wan, Xianchong; Lieffers, Victor J

2016-05-01

This study tested how wind in daytime and nighttime affects hydraulic properties and thigmomorphogenic response of poplar saplings. It shows that wind in daytime interrupted water balance of poplar plants by aggravating cavitation in the stem xylem under high xylem tension in the daytime, reducing water potential in midday and hence reducing gas exchange, including stomatal conductance and CO2 assimilation. The wind blowing in daytime significantly reduced plant growth, including height, diameter, leaf size, leaf area, root and whole biomass, whereas wind blowing in nighttime only caused a reduction in radial and height growth at the early stage compared with the control but decreased height:diameter ratios. In summary, the interaction between wind loading and xylem tension exerted a negative impact on water balance, gas exchanges and growth of poplar plants, and wind in nighttime caused only a small thigmomorphogenic response. © 2015 Scandinavian Plant Physiology Society.

A Vision-Based Driver Nighttime Assistance and Surveillance System Based on Intelligent Image Sensing Techniques and a Heterogamous Dual-Core Embedded System Architecture

PubMed Central

Chen, Yen-Lin; Chiang, Hsin-Han; Chiang, Chuan-Yen; Liu, Chuan-Ming; Yuan, Shyan-Ming; Wang, Jenq-Haur

2012-01-01

This study proposes a vision-based intelligent nighttime driver assistance and surveillance system (VIDASS system) implemented by a set of embedded software components and modules, and integrates these modules to accomplish a component-based system framework on an embedded heterogamous dual-core platform. Therefore, this study develops and implements computer vision and sensing techniques of nighttime vehicle detection, collision warning determination, and traffic event recording. The proposed system processes the road-scene frames in front of the host car captured from CCD sensors mounted on the host vehicle. These vision-based sensing and processing technologies are integrated and implemented on an ARM-DSP heterogamous dual-core embedded platform. Peripheral devices, including image grabbing devices, communication modules, and other in-vehicle control devices, are also integrated to form an in-vehicle-embedded vision-based nighttime driver assistance and surveillance system. PMID:22736956

Correlates Among Nocturnal Agitation, Sleep, and Urinary Incontinence in Dementia

PubMed Central

Rose, Karen; Specht, Janet; Forch, Windy

2016-01-01

Family caregivers of elders with dementia often face the challenging behaviors of nighttime agitation, sleep disturbances, and urinary incontinence. To date, no study has examined the interrelationships of these behaviors in community-dwelling persons. This single group, descriptive study employs wireless body sensors to objectively collect data on nighttime agitation, sleep, and urinary incontinence in patients with dementia in their homes over a 5- to 7-day period. The aims are to (1) examine the feasibility and acceptability of the use of body sensors in community-dwelling persons with dementia; (2) describe patterns of nocturnal agitation, sleep continuity and duration, and nighttime urinary incontinence; and (3) examine the relationships among nocturnal agitation, sleep continuity and duration, and nighttime urinary incontinence. Data collection is in early stages and is still in progress. Challenges and advantages from preliminary data collection are reported. PMID:24670931

Effects on sleep disturbance of changes in aircraft noise near three airports.

PubMed

Fidell, S; Pearsons, K; Tabachnick, B G; Howe, R

2000-05-01

Field measurements were conducted of potential sleep disturbance associated with changes in nighttime aircraft noise exposure near three airports. One study was conducted near Stapleton International Airport (DEN) and Denver International Airport (DIA) in anticipation of the closure of the former and opening of the latter. Sleep behavior was monitored in 57 homes located near runway ends at the two airports. A second study was conducted in the vicinity of DeKalb-Peachtree Airport (PDK), a large general aviation airport that expected increased nighttime flight operations due to the Olympic Games in July and August of 1996. Similar methods of measuring nighttime noise levels and sleep disturbance in the two studies were maintained over the course of 2717 and 686 subject-nights of observations, respectively. No major differences in noise-induced sleep disturbance were observed as a function of changes in nighttime aircraft noise exposure.

A vision-based driver nighttime assistance and surveillance system based on intelligent image sensing techniques and a heterogamous dual-core embedded system architecture.

PubMed

Chen, Yen-Lin; Chiang, Hsin-Han; Chiang, Chuan-Yen; Liu, Chuan-Ming; Yuan, Shyan-Ming; Wang, Jenq-Haur

2012-01-01

This study proposes a vision-based intelligent nighttime driver assistance and surveillance system (VIDASS system) implemented by a set of embedded software components and modules, and integrates these modules to accomplish a component-based system framework on an embedded heterogamous dual-core platform. Therefore, this study develops and implements computer vision and sensing techniques of nighttime vehicle detection, collision warning determination, and traffic event recording. The proposed system processes the road-scene frames in front of the host car captured from CCD sensors mounted on the host vehicle. These vision-based sensing and processing technologies are integrated and implemented on an ARM-DSP heterogamous dual-core embedded platform. Peripheral devices, including image grabbing devices, communication modules, and other in-vehicle control devices, are also integrated to form an in-vehicle-embedded vision-based nighttime driver assistance and surveillance system.

Personality traits and circadian blood pressure patterns: A seven year prospective study

PubMed Central

Terracciano, Antonio; Strait, James; Scuteri, Angelo; Meirelles, Osorio; Sutin, Angelina R.; Tarasov, Kirill; Ding, Jun; Marongiu, Michele; Orru, Marco; Pilia, Maria Grazia; Cucca, Francesco; Lakatta, Edward; Schlessinger, David

2014-01-01

Objective A nighttime dip in blood pressure is associated with decreased risk of cardiovascular morbidity and mortality. We examined whether personality traits predict nighttime dipping blood pressure. Methods A community-based sample of 2,848 adults from Sardinia (Italy) completed the Revised NEO Personality Inventory and 7.34-years later (SD=0.87) were examined with 24-hour ambulatory blood pressure monitoring. The primary analyses examined the associations of personality traits with continuous and categorical measures of mean arterial, systolic and diastolic blood pressure nighttime dipping. Results Agreeableness and conscientiousness were associated with more nocturnal blood pressure dipping (β = .05, p=.025 and β = .07, p<.001, respectively) and lower systolic blood pressure at night (β = -.045, p=.018 and β = -.032; p=.072, respectively). Non-dippers were particularly more impulsive (p=.009), less trusting (p=.004), and less self-disciplined (p=.001), but there was no significant association between nocturnal dipping blood pressure and trait anxiety (p=.78) or depression (p=.59). The associations were stronger when comparing extreme dippers (nighttime drop ≥ 20%) to reverse dippers (nighttime increase in blood pressure). Indeed, scoring 1 SD higher on conscientiousness was associated with about 40% reduced risk of reverse dipping (OR = 1.43, CI = 1.08-1.91). Conclusions We found evidence that reduced nighttime blood pressure dipping is associated with antagonism and impulsivity related traits but not with measures of emotional vulnerability. The strongest associations were found with conscientiousness, a trait that may have broad impact on cardiovascular health. PMID:24608035

The effects of napping on cognitive function in preschoolers.

PubMed

Lam, Janet C; Mahone, E Mark; Mason, Thornton; Scharf, Steven M

2011-01-01

To determine the relationship between napping and cognitive function in preschool-aged children. Daytime napping, nighttime sleep, and cognitive function were assessed in 59 typically developing children aged 3 to 5 years, who were enrolled in full-time childcare. Participants wore an actigraphy watch for 7 days to measure sleep and napping patterns and completed neuropsychological testing emphasizing attention, response control, and vocabulary. Parents of participants completed behavior ratings and sleep logs during the study. Sleep/wake cycles were scored with the Sadeh algorithm. Children who napped more on weekdays were also more likely to nap during weekends. Weekday napping and nighttime sleep were inversely correlated, such that those who napped more slept less at night, although total weekday sleep remained relatively constant. Weekday napping was significantly (negatively) correlated with vocabulary and auditory attention span, and weekday nighttime sleep was positively correlated with vocabulary. Nighttime sleep was also significantly negatively correlated with performance, such that those who slept less at night made more impulsive errors on a computerized go/no-go test. Daytime napping is actually negatively correlated with neurocognitive function in preschoolers. Nighttime sleep seems to be more critical for development of cognitive performance. Cessation of napping may serve as a developmental milestone of brain maturation. Children who nap less do not appear to be sleep deprived, especially if they compensate with increased nighttime sleep. An alternative explanation is that children who sleep less at night are sleep deprived and require a nap. A randomized trial of nap restriction would be the next step in understanding the relationship between napping and neurocognitive performance.

Symptoms of aerophagia are common in patients on continuous positive airway pressure therapy and are related to the presence of nighttime gastroesophageal reflux.

PubMed

Shepherd, Kelly; Hillman, David; Eastwood, Peter

2013-01-15

Continuous positive airway pressure (CPAP), the mainstay treatment for obstructive sleep apnea (OSA), involves administration of air under pressure to the upper airway. A well-known but poorly understood side effect of positive airway pressure therapies is aerophagia, air entering the esophagus and stomach rather than the lungs. Gastric distension, a consequence of aerophagia, can increase gastroesophageal reflux (GER) by increasing transient lower esophageal sphincter relaxations, the most common cause of reflux. This study aimed to determine: (i) the prevalence of aerophagia symptoms in a group of OSA patients on CPAP therapy, and (ii) whether aerophagia symptoms are related to an increase in prevalence of GER symptoms. Consecutive OSA patients undergoing polysomnography for the purpose of optimizing their CPAP therapy completed a validated questionnaire regarding GER symptoms and aerophagia symptoms. Complete datasets were collected for 259 individuals (203 males). The group with aerophagia symptoms (n = 130) had a greater prevalence of frequent (≥ once a week) GER symptoms (29% vs. 10%, p < 0.05) and nighttime GER symptoms (9 vs. 2%, p < 0.05) than those without aerophagia (n = 129). The group with nighttime GER symptoms (n = 27) had a greater prevalence of aerophagia symptoms (63% vs. 23%, p < 0.05) than those without nighttime GER symptoms (n = 232). In patients with OSA being treated with CPAP, the prevalence of GER and nighttime GER symptoms is greater in those with symptoms of aerophagia than those without. CPAP-induced aerophagia might precipitate GER, particularly nighttime GER, by exacerbating transient lower esophageal relaxations through gastric distension.

Nighttime atmospheric chemistry of iodine

NASA Astrophysics Data System (ADS)

Saiz-Lopez, Alfonso; Plane, John M. C.; Cuevas, Carlos A.; Mahajan, Anoop S.; Lamarque, Jean-François; Kinnison, Douglas E.

2016-12-01

Little attention has so far been paid to the nighttime atmospheric chemistry of iodine species. Current atmospheric models predict a buildup of HOI and I2 during the night that leads to a spike of IO at sunrise, which is not observed by measurements. In this work, electronic structure calculations are used to survey possible reactions that HOI and I2 could undergo at night in the lower troposphere, and hence reduce their nighttime accumulation. The new reaction NO3+ HOI → IO + HNO3 is proposed, with a rate coefficient calculated from statistical rate theory over the temperature range 260-300 K and at a pressure of 1000 hPa to be k(T) = 2.7 × 10-12 (300 K/T)2.66 cm3 molecule-1 s-1. This reaction is included in two atmospheric models, along with the known reaction between I2 and NO3, to explore a new nocturnal iodine radical activation mechanism. The results show that this iodine scheme leads to a considerable reduction of nighttime HOI and I2, which results in the enhancement of more than 25 % of nighttime ocean emissions of HOI + I2 and the removal of the anomalous spike of IO at sunrise. We suggest that active nighttime iodine can also have a considerable, so far unrecognized, impact on the reduction of the NO3 radical levels in the marine boundary layer (MBL) and hence upon the nocturnal oxidizing capacity of the marine atmosphere. The effect of this is exemplified by the indirect effect on dimethyl sulfide (DMS) oxidation.

The Effects of Napping on Cognitive Function in Preschoolers

PubMed Central

Lam, Janet C.; Mahone, E. Mark; Mason, Thornton B.A.; Scharf, Steven M.

2011-01-01

Objective To determine the relationship between napping and cognitive function in preschool-aged children. Methods Daytime napping, nighttime sleep and cognitive function were assessed in fifty-nine typically developing children ages 3-5 years, who were enrolled in full-time childcare. Participants wore an actigraphy watch for 7 days to measure sleep and napping patterns, and completed neuropsychological testing emphasizing attention, response control, and vocabulary. Parents of participants completed behavior ratings and sleep logs during the study. Sleep/wake cycles were scored with the Sadeh algorithm. Results Children who napped more on weekdays were also more likely to nap during weekends. Weekday napping and nighttime sleep were inversely correlated, such that those who napped more slept less at night, while total weekday sleep remained relatively constant. Weekday napping was significantly (negatively) correlated with vocabulary and auditory attention span, and weekday nighttime sleep was positively correlated with vocabulary. Nighttime sleep was also significantly negatively correlated with performance, such that those who slept less at night made more impulsive errors on a computerized go/no-go test. Conclusions Daytime napping is actually negatively correlated with neurocognitive function in preschoolers. Nighttime sleep appears to be more critical for development of cognitive performance. Cessation of napping may serve as a developmental milestone of brain maturation. Children who nap less do not appear to be sleep deprived, especially if they compensate with increased nighttime sleep. An alternative explanation is that children who sleep less at night are sleep deprived and require a nap. A randomized trial of nap restriction would be the next step in understanding the relationship between napping and neurocognitive performance. PMID:21217402

Vertically resolved measurements of nighttime radical reservoirs in Los Angeles and their contribution to the urban radical budget.

PubMed

Young, Cora J; Washenfelder, Rebecca A; Roberts, James M; Mielke, Levi H; Osthoff, Hans D; Tsai, Catalina; Pikelnaya, Olga; Stutz, Jochen; Veres, Patrick R; Cochran, Anthony K; VandenBoer, Trevor C; Flynn, James; Grossberg, Nicole; Haman, Christine L; Lefer, Barry; Stark, Harald; Graus, Martin; de Gouw, Joost; Gilman, Jessica B; Kuster, William C; Brown, Steven S

2012-10-16

Photolabile nighttime radical reservoirs, such as nitrous acid (HONO) and nitryl chloride (ClNO(2)), contribute to the oxidizing potential of the atmosphere, particularly in early morning. We present the first vertically resolved measurements of ClNO(2), together with vertically resolved measurements of HONO. These measurements were acquired during the California Nexus (CalNex) campaign in the Los Angeles basin in spring 2010. Average profiles of ClNO(2) exhibited no significant dependence on height within the boundary layer and residual layer, although individual vertical profiles did show variability. By contrast, nitrous acid was strongly enhanced near the ground surface with much smaller concentrations aloft. These observations are consistent with a ClNO(2) source from aerosol uptake of N(2)O(5) throughout the boundary layer and a HONO source from dry deposition of NO(2) to the ground surface and subsequent chemical conversion. At ground level, daytime radical formation calculated from nighttime-accumulated HONO and ClNO(2) was approximately equal. Incorporating the different vertical distributions by integrating through the boundary and residual layers demonstrated that nighttime-accumulated ClNO(2) produced nine times as many radicals as nighttime-accumulated HONO. A comprehensive radical budget at ground level demonstrated that nighttime radical reservoirs accounted for 8% of total radicals formed and that they were the dominant radical source between sunrise and 09:00 Pacific daylight time (PDT). These data show that vertical gradients of radical precursors should be taken into account in radical budgets, particularly with respect to HONO.

Nighttime atmospheric chemistry of iodine

DOE PAGES

Saiz-Lopez, Alfonso; Plane, John M. C.; Cuevas, Carlos A.; ...

2016-12-19

Little attention has so far been paid to the nighttime atmospheric chemistry of iodine species. Current atmospheric models predict a buildup of HOI and I 2 during the night that leads to a spike of IO at sunrise, which is not observed by measurements. In this work, electronic structure calculations are used to survey possible reactions that HOI and I 2 could undergo at night in the lower troposphere, and hence reduce their nighttime accumulation. The new reaction NO 3+ HOI → IO + HNO 3 is proposed, with a rate coefficient calculated from statistical rate theory over the temperaturemore » range 260–300 K and at a pressure of 1000 hPa to be k( T) = 2.7 × 10 -12 (300 K/ T) 2.66 cm 3 molecule -1 s -1. This reaction is included in two atmospheric models, along with the known reaction between I 2 and NO 3, to explore a new nocturnal iodine radical activation mechanism. The results show that this iodine scheme leads to a considerable reduction of nighttime HOI and I 2, which results in the enhancement of more than 25 % of nighttime ocean emissions of HOI + I 2 and the removal of the anomalous spike of IO at sunrise. We suggest that active nighttime iodine can also have a considerable, so far unrecognized, impact on the reduction of the NO 3 radical levels in the marine boundary layer (MBL) and hence upon the nocturnal oxidizing capacity of the marine atmosphere. In conclusion, the effect of this is exemplified by the indirect effect on dimethyl sulfide (DMS) oxidation.« less

Efficacy of nighttime brace in preventing progression of idiopathic scoliosis of less than 25°.

PubMed

Lateur, G; Grobost, P; Gerbelot, J; Eid, A; Griffet, J; Courvoisier, A

2017-04-01

The objective of the present study was to assess, at skeletal maturity, the efficacy of non-operative treatment by isolated nighttime brace in the prevention of progression of progressive idiopathic scoliosis of less than 25°. Isolated nighttime brace treatment is effective in the prevention of progression of mild progressive idiopathic scoliosis (Cobb<25°). A single-center retrospective study included 142 patients managed by nighttime brace for progressive idiopathic scoliosis with Cobb angle<25°, with assessment at skeletal maturity. Mean Cobb angle at start of treatment was 15.5° (range, 10-25°). Mean values for Cobb angle and sagittal parameters before treatment and at skeletal maturity were compared on Student t-test. Change in Cobb angle over time was also analyzed. Mean Cobb angle at skeletal maturity was 16.3°, showing significant increase over baseline (15.5°; P=0.04), although the difference was less than the uncertainty of measurement (±6°). In baseline Risser 0 or 1, mean change in Cobb angle at skeletal maturity (16.2°) was not significant (P=0.1). Cobb angle diminished in 26 cases (18%), increased in 24 (17%) and was unchanged in 92 (65%). The present study confirmed the efficacy of non-operative treatment by nighttime brace in mild progressive idiopathic scoliosis (<25°) in a large majority of cases. A nighttime brace thus seems to be an effective option for the treatment of adolescent scoliosis, ensuring a safe curve of around 20°. Level IV, retrospective study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Nighttime atmospheric chemistry of iodine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saiz-Lopez, Alfonso; Plane, John M. C.; Cuevas, Carlos A.

Little attention has so far been paid to the nighttime atmospheric chemistry of iodine species. Current atmospheric models predict a buildup of HOI and I 2 during the night that leads to a spike of IO at sunrise, which is not observed by measurements. In this work, electronic structure calculations are used to survey possible reactions that HOI and I 2 could undergo at night in the lower troposphere, and hence reduce their nighttime accumulation. The new reaction NO 3+ HOI → IO + HNO 3 is proposed, with a rate coefficient calculated from statistical rate theory over the temperaturemore » range 260–300 K and at a pressure of 1000 hPa to be k( T) = 2.7 × 10 -12 (300 K/ T) 2.66 cm 3 molecule -1 s -1. This reaction is included in two atmospheric models, along with the known reaction between I 2 and NO 3, to explore a new nocturnal iodine radical activation mechanism. The results show that this iodine scheme leads to a considerable reduction of nighttime HOI and I 2, which results in the enhancement of more than 25 % of nighttime ocean emissions of HOI + I 2 and the removal of the anomalous spike of IO at sunrise. We suggest that active nighttime iodine can also have a considerable, so far unrecognized, impact on the reduction of the NO 3 radical levels in the marine boundary layer (MBL) and hence upon the nocturnal oxidizing capacity of the marine atmosphere. In conclusion, the effect of this is exemplified by the indirect effect on dimethyl sulfide (DMS) oxidation.« less

Nighttime Convection, Temperature Inversions, and Diurnal Variations at Low Altitudes in the Martian Tropics

NASA Astrophysics Data System (ADS)

Hinson, D. P.; Haberle, R. M.; Spiga, A.; Tellmann, S.; Paetzold, M.; Asmar, S. W.; Haeusler, B.

2014-07-01

We are using radio occultation measurements and numerical simulations to explore the atmospheric structure and diurnal variations in the lowest few scale heights of the martian atmosphere, with emphasis on nighttime convective layers.

Decision Support Tool for Nighttime Construction and Air Quality - User’s Guide

DOT National Transportation Integrated Search

2017-11-01

The Texas Department of Transportation (TxDOT) Research Project 0-6864 Investigate the Air Quality Benefits of Nighttime Construction in Non-attainment Counties investigated the potential air quality benefits of shifting construction/maintenance acti...

Residential Exposure to Nighttime Retained Heat in the El Paso, Texas, USA Desert Metroplex

NASA Astrophysics Data System (ADS)

Amaya, M. A.; Mohammed, M.; Pingitore, N. E.; Aldouri, R. K.; Benedict, B. A.

2013-12-01

The urban heat island is a well recognized and extensively studied phenomenon that has accelerating importance resulting from two trends associated with world-wide population growth: increasing urbanization and global warming. Urbanization, particularly when unplanned and haphazard, changes such thermal parameters as albedo, surface roughness, and heat capacities of surface materials. Rapid urbanization in the contiguous El Paso, Texas, USA - Ciudad Juarez, Chihuahua, Mexico bi-national metroplex has produced an urban heat island that is warmer than the surrounding Chihuahuan desert (temperature: 35-40 C summer; high elevation: 600-1675 m; rainfall: less than 250 mm annual). Despite the extensive literature on the urban heat island, little is known about urban nighttime land surface temperatures. We employed infrared satellite imaging to establish the variation of nighttime neighborhood surface temperatures across the city of El Paso, as well as all of El Paso County. The underlying purpose of our continuing investigation is to evaluate the geography of morbidity risk: are different neighborhoods at different risk of high nighttime temperatures. Those risks can include heat stress, and irritability and sleep deprivation, with possible resultant violence. Heat exposure at night is significant because residents are at home and 90% of El Pasoans do not have 'refrigerated' air conditioning, but instead have evaporative coolers, which are less expensive to own and operate, but are less effective since they raise the humidity of the partially cooled air. Our geographically weighted regression model showed that both day and nighttime land surface temperatures correlated with the normalized difference vegetation index, population density, and albedo. The association with the index and albedo was stronger during the daytime and with population density during the nighttime. Vegetation (negative) and population density (positive) were the dominant temperature drivers, with albedo and elevation as secondary drivers. Using archived satellite imagery we determined that over the last two decades there has been an increase in both day and nighttime temperatures. With no expected change in urban growth and global warming, local residents will be at increasing risk in the future, as will residents in other urban centers in the desert southwest of the US. We currently are evaluating exposure risk in different population sectors. Do the aged or the poor reside in higher risk neighborhoods? Are there simple measures that can be taken to ameliorate nighttime temperatures?

Association of napping and night-time sleep with impaired glucose regulation, insulin resistance and glycated haemoglobin in Chinese middle-aged adults with no diabetes: a cross-sectional study.

PubMed

Baoying, Huang; Hongjie, Chen; Changsheng, Qiu; Peijian, Wu; Qingfei, Lin; Yinghua, Lin; Huibin, Huang; Jixing, Liang; Liantao, Li; Ling, Chen; Kaka, Tang; Zichun, Chen; Lixiang, Lin; Jieli, Lu; Yufang, Bi; Guang, Ning; Penli, Zhu; Junping, Wen; Gang, Chen

2014-07-23

To assess associations between napping and night-time sleep duration with impaired glucose regulation, insulin resistance (IR) and glycated haemoglobin (HbA1c). Cross-sectional study. Fujian Province, China, from June 2011 to January 2012. This study enrolled 9028 participants aged 40-65 years. Data of 7568 participants with no diabetes were included for analysis. Type 2 diabetes was defined applying WHO criteria. Participants' daytime napping and night-time sleep duration data were collected using a standardised self-reported Chinese-language questionnaire about sleep frequency and quality. Anthropometric and laboratory parameters were also measured. IR was defined as a HOMA-IR index value >2.50. ORs and 95% CIs were derived from multivariate logistic regression models. Participants (mean age 51.1±7.0 years) included 3060 males and 4508 females with average night-time sleep of 7.9 h. A higher proportion of males napped than females. After adjustment for potential confounders, ORs for HbA1c >6.0% were 1.28 and 1.26 for those napping ≤1 h and >1 h (p=0.002 and p=0.018), respectively. Statistically significant differences in IR between nappers and non-nappers were only marginal clinically. Odds for HbA1c >6.0% were significantly lower in participants with longer night-time sleep durations than in the reference group (>8 h vs 6-8 h). Odds for IR were significantly lower in participants whose night-time sleep hours deviated from the reference group (<6 h, >8 h vs 6-8 h) Chinese middle-aged adults with no diabetes who napped had higher HbA1c and IR; those with shorter night-time sleep durations had increased HbA1c. Night-time sleep hours that are either <6 or >8 tend to be associated with lower odds for IR. Further studies are necessary to determine the underlying clinical significance and mechanisms behind these associations. 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.

An intercomparison of the thermal offset for different pyranometers

NASA Astrophysics Data System (ADS)

Sanchez, G.; Cancillo, M. L.; Serrano, A.

2016-07-01

An unprecedented intensive intercomparison campaign focused on the experimental measurement of the thermal offset of pyranometers has been conducted at Badajoz (Spain) with the participation of three main manufacturers. The purpose of this study is to compare the thermal offset of six commercially available pyranometers, being some of them widely used and others recently commercialized. In this campaign, the capping methodology has been used to experimentally measure the daytime thermal offset of the pyranometers. Thus, a short but intense campaign has been conducted in two selected summer days under clear-sky conditions, covering a large range of solar zenith angle, irradiance, and temperature. Along the campaign, a total of 305 capping events have been performed, 61 for each pyranometer. The daytime thermal offset obtained for different pyranometers ranges between 0 and -16.8 W/m2 depending on the environmental conditions, being sometimes notably higher than values estimated indoors by manufacturers. The thermal offset absolute value of all instruments shows a diurnal cycle, increasing from sunrise to central hours of the day and decreasing from midafternoon to sunset. The analysis demonstrates that thermal offset is notably higher and more variable during daytime than during nighttime, requiring specific daytime measurements. Main results emphasize the key role played by wind speed in modulating the thermal offset.

Modelling of light pollution in suburban areas using remotely sensed imagery and GIS.

PubMed

Chalkias, C; Petrakis, M; Psiloglou, B; Lianou, M

2006-04-01

This paper describes a methodology for modelling light pollution using geographical information systems (GIS) and remote sensing (RS) technology. The proposed approach attempts to address the issue of environmental assessment in sensitive suburban areas. The modern way of life in developing countries is conductive to environmental degradation in urban and suburban areas. One specific parameter for this degradation is light pollution due to intense artificial night lighting. This paper aims to assess this parameter for the Athens metropolitan area, using modern analytical and data capturing technologies. For this purpose, night-time satellite images and analogue maps have been used in order to create the spatial database of the GIS for the study area. Using GIS advanced analytical functionality, visibility analysis was implemented. The outputs for this analysis are a series of maps reflecting direct and indirect light pollution around the city of Athens. Direct light pollution corresponds to optical contact with artificial night light sources, while indirect light pollution corresponds to optical contact with the sky glow above the city. Additionally, the assessment of light pollution in different periods allows for dynamic evaluation of the phenomenon. The case study demonstrates high levels of light pollution in Athens suburban areas and its increase over the last decade.

Estimation of Surface Air Temperature from MODIS 1km Resolution Land Surface Temperature Over Northern China

NASA Technical Reports Server (NTRS)

Shen, Suhung; Leptoukh, Gregory G.; Gerasimov, Irina

2010-01-01

Surface air temperature is a critical variable to describe the energy and water cycle of the Earth-atmosphere system and is a key input element for hydrology and land surface models. It is a very important variable in agricultural applications and climate change studies. This is a preliminary study to examine statistical relationships between ground meteorological station measured surface daily maximum/minimum air temperature and satellite remotely sensed land surface temperature from MODIS over the dry and semiarid regions of northern China. Studies were conducted for both MODIS-Terra and MODIS-Aqua by using year 2009 data. Results indicate that the relationships between surface air temperature and remotely sensed land surface temperature are statistically significant. The relationships between the maximum air temperature and daytime land surface temperature depends significantly on land surface types and vegetation index, but the minimum air temperature and nighttime land surface temperature has little dependence on the surface conditions. Based on linear regression relationship between surface air temperature and MODIS land surface temperature, surface maximum and minimum air temperatures are estimated from 1km MODIS land surface temperature under clear sky conditions. The statistical errors (sigma) of the estimated daily maximum (minimum) air temperature is about 3.8 C(3.7 C).

Scopes for Schools: A Low-Cost Model for Bringing Hands-On Astronomy to the K-12 Classroom

NASA Astrophysics Data System (ADS)

Stassun, K. G.; Lattis, J.

1999-12-01

We present a low-cost, field-tested model for astronomy and space-related outreach aimed at minority and under-serviced populations at the middle-school and high-school levels. The model centers around the creation of an extracurricular astronomy ``club" at a middle school or high school, and an in-service training activity for teachers who will serve as club leaders. Students in the club engage in two hands-on activities: telescope-building and model rocketry. Implementation of the model requires a time investment of 1--2 hours per week over the course of one school year. The primary end products are (1) an ongoing extracurricular school club with trained teacher-leaders, (2) a set of portable Dobsonian telescopes for night-time sky-viewing sessions performed by the club as a service to the community, and (3) basic materials for continued model-rocketry activities. In its ideal implementation, the model brings together teachers and amateur astronomers in a lasting partnership. A specific example for funding an outreach program based on this model is presented. This outreach development was funded by a Special Initiatives outreach grant from the Wisconsin Space Grant Consortium, and by the UW-Madison College Access Program. Additional support was provided by Madison's amateur astronomy organization, the Madison Astronomical Society.

Bringing Astronomy to the Classroom: A Model for Planting Seeds of Interest

NASA Astrophysics Data System (ADS)

Stassun, K. G.; Lattis, J.

1999-05-01

We present a low-cost, field-tested model for astronomy and space-related outreach aimed at minority and under-serviced populations at the middle-school and high-school levels. The model centers around the creation of an extracurricular astronomy ``club" at a middle school or high school, and an in-service training activity for teachers who will serve as club leaders. Students in the club engage in two hands-on activities: telescope-building and model rocketry. Implementation of the model requires a time investment of 1--2 hours per week over the course of one school year. The primary end products are (1) an ongoing extracurricular school club with trained teacher-leaders, (2) a set of portable Dobsonian telescopes for night-time sky-viewing sessions performed by the club as a service to the community, and (3) basic materials for continued model-rocketry activities. In its ideal implementation, the model brings together teachers and amateur astronomers in a lasting partnership. A specific example for funding an outreach program based on this model is presented. This outreach development was funded by a Special Initiatives outreach grant from the Wisconsin Space Grant Consortium, and by the UW-Madison College Access Program. Additional support was provided by Madison's organization of amateur astronomers, the Madison Astronomical Society.

Cost-benefit analysis of sequential warning lights in nighttime work zone tapers.

DOT National Transportation Integrated Search

2011-06-01

Improving safety at nighttime work zones is important because of the extra visibility concerns. The deployment of sequential lights is an innovative method for improving driver recognition of lane closures and work zone tapers. Sequential lights are ...

0-6781 : improved nighttime work zone channelization in confined urban projects.

DOT National Transportation Integrated Search

2014-08-01

Turning into and out of driveways in confined or : dense urban work zones can present significant : challenges to drivers, especially during nighttime : conditions when other visual cues about the : driveways may be masked in the dark. These : challe...

Unintended environmental impacts of nighttime freight logistics activities

DOT National Transportation Integrated Search

2010-10-01

In recent years, the reduction of freight vehicle trips during peak hours has been a common : policy goal. To this end, policies have been implemented to shift logistics operations to : nighttime hours. The purpose of such policies has generally been...

Evaluation of the first year of the Washington nighttime seat belt enforcement program.

DOT National Transportation Integrated Search

2010-12-01

The Washington Traffic Safety Commission (WTSC) received funding from the National Highway Traffic Safety Administration to conduct a high-visibility nighttime seat belt enforcement (NTSBE) program in Washington State. The two-year program is followi...

Nighttime construction: evaluation of construction operations : final report.

DOT National Transportation Integrated Search

2004-05-01

The different aspects that should be considered in making decisions on nighttime construction operations are identified and investigated in light of the current state of knowledge and practice. A state-of-the-art review was conducted of the current p...

Minimum requirements for adequate nighttime conspicuity of highway signs

DOT National Transportation Integrated Search

1988-02-01

A laboratory and field study were conducted to assess the minimum luminance levels of signs to ensure that they will be detected and identified at adequate distances under nighttime driving conditions. A total of 30 subjects participated in the field...

Flight Testing of Night Vision Systems in Rotorcraft (Test en vol de systemes de vision nocturne a bord des aeronefs a voilure tournante)

DTIC Science & Technology

2007-07-01

SAS System Analysis and Studies Panel • SCI Systems Concepts and Integration Panel • SET Sensors and Electronics Technology Panel These...Daylight Readability 4-2 4.1.4 Night-Time Readability 4-2 4.1.5 NVIS Radiance 4-2 4.1.6 Human Factors Analysis 4-3 4.1.7 Flight Tests 4-3 4.1.7.1...position is shadowing. Moonlight creates shadows during night-time just as sunlight does during the day. Understanding what cannot be seen in night-time

Cognitive-behavioral versus non-directive therapy for preschoolers with severe nighttime fears and sleep-related problems.

PubMed

Kahn, Michal; Ronen, Alon; Apter, Alan; Sadeh, Avi

2017-04-01

To compare the efficacy of a developmentally appropriate cognitive-behavioral therapy protocol for preschoolers with severe nighttime fears and sleep-related problems, with an active control treatment. Ninety children aged four to six years (63% boys) with severe nighttime fears and their parents were randomized to either cognitive-behavioral therapy including parent involved play (CBT-PIP) or to a structurally equivalent non-directive treatment (TEPT; triadic expressive play therapy). Treatment conditions were also equivalent in parent- and child-rated credibility and expectancy, and in therapist-rated compliance. Children and parents were assessed at baseline, during the first intervention week and four weeks after treatment. Measures included actigraphy, daily sleep logs, structured diagnostic interviews and parent questionnaires. Significant reductions were observed in nighttime fears and objectively and subjectively measured sleep disruptions in both intervention groups following treatment. Parent reports indicated more advantageous outcomes for CBT-PIP compared to TEPT, with greater reductions in sleep problems and co-sleeping as well as higher customer satisfaction in the former group. While CBT-PIP showed no significant advantage compared to the active control in reducing fears or in improving objectively measured sleep, it was significantly more beneficial in reducing the adverse behavioral features of nighttime fears. Copyright © 2016 Elsevier B.V. All rights reserved.

Nighttime Look at Ambrym Volcano, Vanuatu by NASA Spacecraft

NASA Image and Video Library

2014-02-12

Ambrym volcano in Vanuatu is one of the most active volcanoes in the world. A large summit caldera contains two active vent complexes, Marum and Benbow is seen in this February 12, 2014 nighttime thermal infrared image from NASA Terra spacecraft.

Guidelines to observe and estimate statewide seat belt use at night.

DOT National Transportation Integrated Search

2010-03-01

Research has shown that nighttime seat belt use is lower than daytime use. There is also an overrepresentation : of fatal crashes at night. Therefore a proper estimate of statewide nighttime seat belt use would be beneficial to : understanding the pr...

Artificial Outdoor Nighttime Lights Associate with Altered Sleep Behavior in the American General Population

PubMed Central

Ohayon, Maurice M.; Milesi, Cristina

2016-01-01

Study Objectives: Our study aims to explore the associations between outdoor nighttime lights (ONL) and sleep patterns in the human population. Methods: Cross-sectional telephone study of a representative sample of the general US population age 18 y or older. 19,136 noninstitutionalized individuals (participation rate: 83.2%) were interviewed by telephone. The Sleep-EVAL expert system administered questions on life and sleeping habits; health; sleep, mental and organic disorders (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision; International Classification of Sleep Disorders, Second Edition; International Classification of Diseases, 10th Edition). Individuals were geolocated by longitude and latitude. Outdoor nighttime light measurements were obtained from the Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS), with nighttime passes taking place between 19:30 and 22:30 local time. Light data were correlated precisely to the geolocation of each participant of the general population sample. Results: Living in areas with greater ONL was associated with delayed bedtime (P < 0.0001) and wake up time (P < 0.0001), shorter sleep duration (P < 0.01), and increased daytime sleepiness (P < 0.0001). Living in areas with greater ONL also increased the dissatisfaction with sleep quantity and quality (P < 0.0001) and the likelihood of having a diagnostic profile congruent with a circadian rhythm disorder (P < 0.0001). Conclusions: Although they improve the overall safety of people and traffic, nighttime lights in our streets and cities are clearly linked with modifications in human sleep behaviors and also impinge on the daytime functioning of individuals living in areas with greater ONL. Citation: Ohayon MM, Milesi C. Artificial outdoor nighttime lights associate with altered sleep behavior in the american general population. SLEEP 2016;39(6):1311–1320. PMID:27091523

Constraining Night Time Ecosystem Respiration by Inverse Approaches

NASA Astrophysics Data System (ADS)

Juang, J.; Stoy, P. C.; Siqueira, M. B.; Katul, G. G.

2004-12-01

Estimating nighttime ecosystem respiration remains a key challenge in quantifying ecosystem carbon budgets. Currently, nighttime eddy-covariance (EC) flux measurements are plagued by uncertainties often attributed to poor mixing within the canopy volume, non-turbulent transport of CO2 into and out of the canopy, and non-stationarity and intermittency. Here, we explore the use of second-order closure models to estimate nighttime ecosystem respiration by mathematically linking sources of CO2 to mean concentration profiles via the continuity and the CO2 flux budget equation modified to include thermal stratification. By forcing this model to match, in a root-mean squared sense, the nighttime measured mean CO2 concentration profiles within the canopy the above ground CO2 production and forest floor respiration can be estimated via multi-dimensional optimization techniques. We show that in a maturing pine and a mature hardwood forest, these optimized CO2 sources are (1) consistently larger than the eddy covariance flux measurements above the canopy, and (2) agree well with chamber-based measurements. We also show that by linking the optimized nighttime ecosystem respiration to temperature measurements, the estimated annual ecosystem respiration from this approach agrees well with biometric estimates, at least when compared to eddy-covariance methods conditioned on a friction velocity threshold. The difference between the annual ecosystem respiration obtained by this optimization method and the friction-velocity thresholded night-time EC fluxes can be as large as 700 g C m-2 (in 2003) for the maturing pine forest, which is about 40% of the ecosystem respiration. For 2001 and 2002, the annual ecosystem respiration differences between the EC-based and the proposed approach were on the order of 300 to 400 g C m-2.

Night Work and the Risk of Depression.

PubMed

Angerer, Peter; Schmook, Renate; Elfantel, Irina; Li, Jian

2017-07-16

Working the night shift interferes with the circadian chronobiological rhythm, causing sleep disturbances, fatigue, and diminished wellbeing, and increases the risk of serious disease. The question whether night work increases the risk of depression has not been adequately studied to date. We carried out a systematic, broadly conceived literature search in the PubMed, Scopus, PsycINFO, and PSYNDEX databases and the Medpilot search portal on the topic of nighttime shift work and mental illness. The search yielded 5682 hits, which were narrowed down by predefined selection criteria to 11 high-quality longitudinal studies on the relationship between nighttime shift work and depressive illness. Only these 11 studies were subjected to further analysis. 3 of 4 studies on nighttime shift work in the health professions (almost exclusively nursing) revealed no association with depression over an observation period of two years. On the other hand, 5 studies on nighttime shift work in occupations outside the health sector, with observation periods of two or more years, yielded evidence of an elevated risk of depression after several years of nighttime shift work, but not in any uniform pattern. A supplementary meta-analysis of 5 of the studies revealed a 42% increase of the risk of depression among persons working the night shift (95% confidence interval [0.92; 2.19]). Psychosocial working conditions that have a negative influence on health partially account for these associations. Although there is evidence that nighttime shift work (at least, in occupations outside the health sector) does increase the risk of depression, this evidence is not strong enough to sustain a general medical recommendation against shift work for employees with depressive conditions. It would seem appropriate to address this question on an individual basis, with strong support from physicians and close attention to the deleterious psychosocial factors associated with shift work.

Night Shift Work and Levels of 6-Sulfatoxymelatonin and Cortisol in Men

PubMed Central

Mirick, Dana K.; Bhatti, Parveen; Chen, Chu; Nordt, Frank; Stanczyk, Frank Z.; Davis, Scott

2016-01-01

Background Nightshift work is associated with cancer among men, but the biological mechanism is unclear. We investigated whether male nightshift workers demonstrated changes in levels of melatonin and cortisol, potential biomarkers of cancer risk. Methods Urine was collected from 185 nightshift and 158 dayshift-working male healthcare providers, aged 22-55, throughout work and sleep periods and assayed for 6-sulfatoxymelatonin and cortisol. Morning serum was collected within 90 minutes of completing the night and assayed for cortisol. Results Nightshift workers had significantly lower 6-sulfatoxymelatonin levels during daytime sleep, nighttime work, and nighttime sleep on off-nights (57%, 62% and 40% lower, respectively), relative to the dayshift workers during nighttime sleep (p<0.0001); urinary cortisol in nightshift workers was 16% higher during daytime sleep and 13% lower during nighttime sleep on off-nights (p<0.05). Morning serum cortisol post-work and post-sleep in nightshift workers were 24% and 43% lower, respectively, than post-sleep levels among dayshift workers (p<0.0001). Within-subject comparisons among the nightshift workers revealed significantly lower melatonin levels and significantly higher urinary cortisol levels during daytime sleep and nighttime work, relative to nighttime sleep (p<0.01); morning serum cortisol levels post-work were lower than those post-sleep. Conclusions Nightshift workers have substantially lower 6-sulfatoxymelatonin during night work and daytime sleep, and levels remain low when nightshift workers sleep at night. Chronic reduction in melatonin among nightshift workers may be an important carcinogenic mechanism. Cortisol secretion patterns may be impacted by night shift work, which could affect cancer risk. Impact Shiftwork could be an important risk factor for many types of cancer. PMID:23563887

Night shift work and levels of 6-sulfatoxymelatonin and cortisol in men.

PubMed

Mirick, Dana K; Bhatti, Parveen; Chen, Chu; Nordt, Frank; Stanczyk, Frank Z; Davis, Scott

2013-06-01

Night shift work is associated with cancer among men, but the biologic mechanism is unclear. We investigated whether male night shift workers showed changes in levels of melatonin and cortisol, potential biomarkers of cancer risk. Urine was collected from 185 night shift and 158 day shift-working male healthcare providers, aged 22 to 55 years, throughout work and sleep periods, and assayed for 6-sulfatoxymelatonin and cortisol. Morning serum was collected within 90 minutes of completing the night and assayed for cortisol. Night shift workers had significantly lower 6-sulfatoxymelatonin levels during daytime sleep, nighttime work, and nighttime sleep on off-nights (57%, 62%, and 40% lower, respectively), relative to the day shift workers during nighttime sleep (P < 0.0001); urinary cortisol in night shift workers was 16% higher during daytime sleep and 13% lower during nighttime sleep on off-nights (P < 0.05). Morning serum cortisol post-work and post-sleep in night shift workers were 24% and 43% lower, respectively, than post-sleep levels among day shift workers (P < 0.0001). Within-subject comparisons among the night shift workers revealed significantly lower melatonin levels and significantly higher urinary cortisol levels during daytime sleep and nighttime work, relative to nighttime sleep (P < 0.01); morning serum cortisol levels post-work were lower than those post-sleep. Night shift workers have substantially lower 6-sulfatoxymelatonin during night work and daytime sleep, and levels remain low when night shift workers sleep at night. Chronic reduction in melatonin among night shift workers may be an important carcinogenic mechanism. Cortisol secretion patterns may be impacted by night shift work, which could affect cancer risk. Shift work could be an important risk factor for many types of cancer.

Sleep-promoting effects of a GABA/5-HTP mixture: Behavioral changes and neuromodulation in an invertebrate model.

PubMed

Hong, Ki-Bae; Park, Yooheon; Suh, Hyung Joo

2016-04-01

This study was to investigate the sleep promoting effects of combined γ-aminobutyric acid (GABA) and 5-hydroxytryptophan (5-HTP), by examining neuronal processes governing mRNA level alterations, as well as assessing neuromodulator concentrations, in a fruit fly model. Behavioral assays were applied to investigate subjective nighttime activity, sleep episodes, and total duration of subjective nighttime sleep of two amino acids and GABA/5-HTP mixture with caffeine treated flies. Also, real-time PCR and HPLC analysis were applied to analyze the signaling pathway. Subjective nighttime activity and sleep patterns of individual flies significantly decreased with 1% GABA treatment in conjunction with 0.1% 5-HTP treatment (p<0.001). Furthermore, GABA/5-HTP mixture resulted in significant differences between groups related to sleep patterns (40%, p<0.017) and significantly induced subjective nighttime sleep in the awake model (p<0.003). These results related to transcript levels of the GABAB receptor (GABAB-R1) and serotonin receptor (5-HT1A), compared to the control group. In addition, GABA/5-HTP mixture significantly increased GABA levels 1h and 12h following treatment (2.1 fold and 1.2 fold higher than the control, respectively) and also increased 5-HTP levels (0 h: 1.01 μg/protein, 12h: 3.45 μg/protein). In this regard, we successfully demonstrated that using a GABA/5-HTP mixture modulates subjective nighttime activity, sleep episodes, and total duration of subjective nighttime sleep to a greater extent than single administration of each amino acid, and that this modulation occurs via GABAergic and serotonergic signaling. Copyright © 2016 Elsevier Inc. All rights reserved.

Identifying targets for improvement in nighttime seat belt use : traffic tech.

DOT National Transportation Integrated Search

2010-07-01

Previous research has found that the proportion of unbelted : fatalities is greater at night than during the day. Failure to use : seat belts has been identified as an important factor in nighttime : fatalities, yet there are still many gaps in our k...

Nighttime enforcement of seat belt laws: an evaluation of three community programs : traffic tech.

DOT National Transportation Integrated Search

2010-04-01

Enforcement of seat belt laws has been conducted largely : during daylight hours. Daytime enforcement programs : have worked well to improve observed belt use rates during : the day, but have been shown less often to affect nighttime : use. Fatality ...

Daytime and nighttime seat belt use at selected sites in New Mexico

DOT National Transportation Integrated Search

2007-01-01

Observational surveys of seat belt use were conducted at 108 observation sites across New Mexico during both daytime and nighttime hours. Belt use at night measured 6.2 percentage points lower than daytime. Belt use was related to sex, vehicle type, ...

Unusual Sleep Experiences, Dissociation, and Schizotypy: Evidence for a Common Domain

PubMed Central

Koffel, Erin; Watson, David

2009-01-01

This paper reviews studies that have examined associations between unusual sleep experiences (including nightmares, vivid dreaming, narcolepsy symptoms, and complex nighttime behaviors) and dissociation and schizotypy. Using correlational studies and structural analyses, evidence is provided that unusual sleep experiences, dissociation, and schizotypy belong to a common domain. It is demonstrated that unusual sleep experiences show specificity to dissociation and schizotypy compared to other daytime symptoms (e.g., anxiety, depression, substance use) and other sleep disturbances (e.g., insomnia, lassitude/fatigue). The paper also outlines the methodological limitations of the existing evidence and makes suggestions for future research. Finally, three models for the overlap of daytime and nighttime symptoms are reviewed, including biological abnormalities, trauma, and personality traits. Although further research is needed, it is suggested that daytime and nighttime symptoms result from problems with sleep-wake state boundaries, which may be precipitated by stress or trauma. In addition, association between daytime and nighttime symptoms can be attributed to the higher order personality trait of Oddity. PMID:19581031

Shadow Detection Based on Regions of Light Sources for Object Extraction in Nighttime Video

PubMed Central

Lee, Gil-beom; Lee, Myeong-jin; Lee, Woo-Kyung; Park, Joo-heon; Kim, Tae-Hwan

2017-01-01

Intelligent video surveillance systems detect pre-configured surveillance events through background modeling, foreground and object extraction, object tracking, and event detection. Shadow regions inside video frames sometimes appear as foreground objects, interfere with ensuing processes, and finally degrade the event detection performance of the systems. Conventional studies have mostly used intensity, color, texture, and geometric information to perform shadow detection in daytime video, but these methods lack the capability of removing shadows in nighttime video. In this paper, a novel shadow detection algorithm for nighttime video is proposed; this algorithm partitions each foreground object based on the object’s vertical histogram and screens out shadow objects by validating their orientations heading toward regions of light sources. From the experimental results, it can be seen that the proposed algorithm shows more than 93.8% shadow removal and 89.9% object extraction rates for nighttime video sequences, and the algorithm outperforms conventional shadow removal algorithms designed for daytime videos. PMID:28327515

Urban Summertime Ozone of China: Peak Ozone Hour and Nighttime Mixing

NASA Astrophysics Data System (ADS)

Qu, H.; Wang, Y.; Zhang, R.

2017-12-01

We investigate the observed diurnal cycle of summertime ozone in the cities of China using a regional chemical transport model. The simulated daytime ozone is in general agreement with the observations. Model simulations suggest that the ozone peak time and peak concentration are a function of NOx (NO + NO2) and volatile organic compound (VOC) emissions. The differences between simulated and observed ozone peak time and peak concentration in some regions can be applied to understand biases in the emission inventories. For example, the VOCs emissions are underestimated over the Pearl River Delta (PRD) region, and either NOx emissions are underestimated or VOC emissions are overestimated over the Yangtze River Delta (YRD) regions. In contrast to the general good daytime ozone simulations, the simulated nighttime ozone has a large low bias of up to 40 ppbv. Nighttime ozone in urban areas is sensitive to the nocturnal boundary-layer mixing, and enhanced nighttime mixing (from the surface to 200-500 m) is necessary for the model to reproduce the observed level of ozone.

Adverse Health Effects of Nighttime Lighting

NASA Astrophysics Data System (ADS)

Motta, M.

2012-06-01

The effects of poor lighting and glare on public safety are well-known, as are the harmful environmental effects on various species and the environment in general. What is less well-known is the potential harmful medical effects of excessive poor nighttime lighting. A significant body of research has been developed over the last few years regarding this problem. One of the most significant effects is the startling increased risk for breast cancer by excessive exposure to nighttime lighting. The mechanism is felt to be by disruption of the circadian rhythm and suppression of melatonin production from the pineal gland. Melatonin has an anticancer effect that is lost when its production is disrupted. I am in the process of developing a monograph that will summarize this important body of research, to be presented and endorsed by the American Medical Association, and its Council of Science and Public health. This paper is a brief overall summary of this little known potential harmful effect of poor and excessive nighttime lighting.

Loxoprofen sodium treatment for elderly men with refractory nocturia: effect on night-time urine production.

PubMed

Okada, Shinsuke; Watanabe, Hideki; Kojima, Yoshiyuki; Yanai, Yoshimasa; Sasaki, Shoichi; Kohri, Kenjiro

2008-05-01

We evaluated the efficacy of loxoprofen sodium for refractory nocturia. Twelve men (mean age, 75.1 +/- 5.7) with nocturia were enrolled in this study. All patients received 60 mg loxoprofen sodium prior to sleeping at night for 14 days. Nine of 12 patients (75%) felt more satisfaction than previous treatments. Patients were grouped into a loxoprofen sodium-effective (n = 7) and ineffective groups (n = 5) based on the results of the frequency-volume chart. In the effective group, interestingly, night-time urine volume showed significant reduction (P < 0.05). On the other hand, the average single voided volume at night and 24-h urine volume showed no significant change. There was a statistically significant difference in the night-time urine volume after treatment between groups (P < 0.01). Loxoprofen sodium is an effective treatment for some patients with refractory nocturia. The main effect mechanism of loxoprofen sodium may involve the reduction of night-time urine production.

Robust Behavior Recognition in Intelligent Surveillance Environments.

PubMed

Batchuluun, Ganbayar; Kim, Yeong Gon; Kim, Jong Hyun; Hong, Hyung Gil; Park, Kang Ryoung

2016-06-30

Intelligent surveillance systems have been studied by many researchers. These systems should be operated in both daytime and nighttime, but objects are invisible in images captured by visible light camera during the night. Therefore, near infrared (NIR) cameras, thermal cameras (based on medium-wavelength infrared (MWIR), and long-wavelength infrared (LWIR) light) have been considered for usage during the nighttime as an alternative. Due to the usage during both daytime and nighttime, and the limitation of requiring an additional NIR illuminator (which should illuminate a wide area over a great distance) for NIR cameras during the nighttime, a dual system of visible light and thermal cameras is used in our research, and we propose a new behavior recognition in intelligent surveillance environments. Twelve datasets were compiled by collecting data in various environments, and they were used to obtain experimental results. The recognition accuracy of our method was found to be 97.6%, thereby confirming the ability of our method to outperform previous methods.

The Value of Darkness: A Moral Framework for Urban Nighttime Lighting.

PubMed

Stone, Taylor

2018-04-01

The adverse effects of artificial nighttime lighting, known as light pollution, are emerging as an important environmental issue. To address these effects, current scientific research focuses mainly on identifying what is bad or undesirable about certain types and uses of lighting at night. This paper adopts a value-sensitive approach, focusing instead on what is good about darkness at night. In doing so, it offers a first comprehensive analysis of the environmental value of darkness at night from within applied ethics. A design for values orientation is utilized to conceptualize, define, and categorize the ways in which value is derived from darkness. Nine values are identified and categorized via their type of good, temporal outlook, and spatial characteristics. Furthermore, these nine values are translated into prima facie moral obligations that should be incorporated into future design choices, policy-making, and innovations to nighttime lighting. Thus, the value of darkness is analyzed with the practical goal of informing future decision-making about urban nighttime lighting.

Inferring Nighttime Ionospheric Parameters with the Far Ultraviolet Imager Onboard the Ionospheric Connection Explorer

NASA Astrophysics Data System (ADS)

Kamalabadi, Farzad; Qin, Jianqi; Harding, Brian J.; Iliou, Dimitrios; Makela, Jonathan J.; Meier, R. R.; England, Scott L.; Frey, Harald U.; Mende, Stephen B.; Immel, Thomas J.

2018-06-01

The Ionospheric Connection Explorer (ICON) Far Ultraviolet (FUV) imager, ICON FUV, will measure altitude profiles of OI 135.6 nm emissions to infer nighttime ionospheric parameters. Accurate estimation of the ionospheric state requires the development of a comprehensive radiative transfer model from first principles to quantify the effects of physical processes on the production and transport of the 135.6 nm photons in the ionosphere including the mutual neutralization contribution as well as the effect of resonant scattering by atomic oxygen and pure absorption by oxygen molecules. This forward model is then used in conjunction with a constrained optimization algorithm to invert the anticipated ICON FUV line-of-sight integrated measurements. In this paper, we describe the connection between ICON FUV measurements and the nighttime ionosphere, along with the approach to inverting the measured emission profiles to derive the associated O+ profiles from 150-450 km in the nighttime ionosphere that directly reflect the electron density in the F-region of the ionosphere.

Nighttime aqueous-phase secondary organic aerosols in Los Angeles and its implication for fine particulate matter composition and oxidative potential

NASA Astrophysics Data System (ADS)

Saffari, Arian; Hasheminassab, Sina; Shafer, Martin M.; Schauer, James J.; Chatila, Talal A.; Sioutas, Constantinos

2016-05-01

Recent investigations suggest that aqueous phase oxidation of hydrophilic organic compounds can be a significant source of secondary organic aerosols (SOA) in the atmosphere. Here we investigate the possibility of nighttime aqueous phase formation of SOA in Los Angeles during winter, through examination of trends in fine particulate matter (PM2.5) carbonaceous content during two contrasting seasons. Distinctive winter and summer trends were observed for the diurnal variation of organic carbon (OC) and secondary organic carbon (SOC), with elevated levels during the nighttime in winter, suggesting an enhanced formation of SOA during that period. The nighttime ratio of SOC to OC was positively associated with the relative humidity (RH) at high RH levels (above 70%), which is when the liquid water content of the ambient aerosol would be high and could facilitate dissolution of hydrophilic primary organic compounds into the aqueous phase. Time-integrated collection and analysis of wintertime particles at three time periods of the day (morning, 6:00 a.m.-9:00 a.m.; afternoon, 11:00 a.m.-3:00 p.m.; night, 8:00 p.m.-4:00 a.m.) revealed higher levels of water soluble organic carbon (WSOC) and organic acids during the night and afternoon periods compared to the morning period, indicating that the SOA formation in winter continues throughout the nighttime. Furthermore, diurnal trends in concentrations of semi-volatile organic compounds (SVOCs) from primary emissions showed that partitioning of SVOCs from the gas to the particle phase due to the decreased nighttime temperatures cannot explain the substantial OC and SOC increase at night. The oxidative potential of the collected particles (quantified using a biological macrophage-based reactive oxygen species assay, in addition to the dithiothreitol assay) was comparable during afternoon and nighttime periods, but higher (by at least ∼30%) compared to the morning period, suggesting that SOA formation processes possibly enhance the toxicity of the ambient particles compared to mobile-source dominated primary emissions in the Los Angeles area.

Association of shift-work, daytime napping, and nighttime sleep with cancer incidence and cancer-caused mortality in Dongfeng-tongji cohort study.

PubMed

Bai, Yansen; Li, Xiaoliang; Wang, Ke; Chen, Shi; Wang, Suhan; Chen, Zhuowang; Wu, Xiulong; Fu, Wenshan; Wei, Sheng; Yuan, Jing; Yao, Ping; Miao, Xiaoping; Zhang, Xiaomin; He, Meian; Yang, Handong; Wu, Tangchun; Guo, Huan

2016-12-01

Few studies investigated the combined effects of night-shift work, daytime napping, and nighttime sleep on cancer incidence and mortality. A total of 25,377 participants were included in this study. Information on sleep habits, cancer incidences, and mortalities were collected. Cox proportional hazards models were used to calculate the adjusted hazard ratios and 95% confidence intervals (HRs, 95%CIs). Male subjects experienced ≥20 years of night-shift work, or without daytime napping had an increased risk of cancer, when compared with males who did not have night-shift work or napped for 1-30 min [HR (95%CI) = 1.27 (1.01-1.59) and 2.03 (1.01-4.13), respectively]. Nighttime sleep for ≥10 h was associated with a separate 40% and 59% increased risk of cancer [HR (95%CI) = 1.40 (1.04-1.88)] and cancer-caused mortality [HR (95%CI) = 1.59 (1.01-2.49)] than sleep for 7-8 h/night. Combined effects of three sleep habits were further identified. Male participants with at least two above risk sleep habits had a 43% increased risk of cancer [HR (95%CI) = 1.43 (1.07-2.01)] and a 2.07-fold increased cancer-caused mortality [HR (95%CI) = 2.07 (1.25-3.29)] than those who did not have any above risk sleep habits. However, no significant associations were observed among women. Long night-shift work history, without daytime napping, and long nighttime sleep duration were independently and jointly associated with higher cancer incidence among males. KEY MESSAGES Night-shift work of ≥20 years, without napping, and nighttime sleep of ≥10 h were associated with increased cancer incidence. Nighttime sleep ≥10 h was associated with a 2.07-fold increased cancer-caused mortality among males. Combined effects of night-shift work ≥20 years, without napping, and nighttime sleep ≥10 h on increasing cancer incidence were existed among males.

Nighttime driving and fatal crash involvement of teenagers.

PubMed

Williams, A F

1985-02-01

Data from the 1977 National Personal Transportation Survey and from the Fatal Accident Reporting System were used to compute mileage-based fatal crash involvement rates of drivers, by age, sex, and time of day. Teenagers drive less than older drivers but do more of their driving at night. They have much higher numbers of drivers in fatal crashes based on miles driven than do older drivers; their nighttime rates are particularly high. Sixteen year olds, especially males, have by far the highest fatal crash rates per mile, both nighttime and daytime. More widespread adoption of driving curfew laws would very likely produce substantial reductions in fatalities involving 16 yr old drivers.

Recognition of rail car retroreflective patterns for improving nighttime conspicuity

DOT National Transportation Integrated Search

2001-07-01

Every year in the United States, accidents at highway-railroad grade crossings take place where the motorist hits the side of the train at night. In a portion of these nighttime accidents, the motorist fails to see the train in the grade crossing. On...

Development, design, and flight test evaluation of a continuous descent approach procedure for nighttime operation at Louisville International Airport.

DOT National Transportation Integrated Search

2006-01-09

The design and flight test of a Continuous Descent Approach (CDA) : procedure for regular nighttime operation at Louisville : International Airport are described in this report. Results of : the analyses of aircraft and FMS performance indicate that ...

Stomata open at night in pole-sized and mature ponderosa pine: implications for O3 exposure metrics.

PubMed

Grulke, N E; Alonso, R; Nguyen, T; Cascio, C; Dobrowolski, W

2004-09-01

Ponderosa pine (Pinus ponderosa Dougl. ex Laws.) is widely distributed in the western USA. We report the lack of stomatal closure at night in early summer for ponderosa pine at two of three sites investigated. Trees at a third site with lower nitrogen dioxide and nitric acid exposure, but greater drought stress, had slightly open stomata at night in early summer but closed stomata at night for the rest of the summer. The three sites had similar background ozone exposure during the summer of measurement (2001). Nighttime stomatal conductance (gs) ranged from one tenth to one fifth that of maximum daytime values. In general, pole-sized trees (< 40 years old) had greater nighttime gs than mature trees (> 250 years old). In late summer, nighttime gs was low (< 3.0 mmol H2O m(-2) s(-1)) for both tree size classes at all sites. Measurable nighttime gs has also been reported in other conifers, but the values we observed were higher. In June, nighttime ozone (O3) uptake accounted for 9, 5 and 3% of the total daily O3 uptake of pole-sized trees from west to east across the San Bernardino Mountains. In late summer, O3 uptake at night was < 2% of diel uptake at all sites. Nocturnal O3 uptake may contribute to greater oxidant injury development, especially in pole-sized trees in early summer.

Napping, Nighttime Sleep, and Cardiovascular Risk Factors in Mid-Life Adults

PubMed Central

Owens, Jane F.; Buysse, Daniel J.; Hall, Martica; Kamarck, Thomas W.; Lee, Laisze; Strollo, Patrick J.; Reis, Steven E.; Matthews, Karen A.

2010-01-01

Study Objectives: To evaluate the relations between sleep characteristics and cardiovascular risk factors and napping behavior, and to assess whether daytime napping leads to subsequent better or worse sleep. Methods: The sample consisted of 224 (African American, Caucasian, and Asian) middle-aged men and women. Sleep measures included nine nights of actigraphy and sleep diaries, sleep questionnaires, and one night of polysomnography to measure sleep disordered breathing. Results: More frequent napping was associated with shorter nighttime sleep duration averaged across the nine nights of actigraphy (especially among African Americans), more daytime sleepiness, more pain and fatigue by diary, and increased body mass index and waist circumference. Shorter nighttime sleep duration was associated with taking a nap during the next day and taking a nap was associated with less efficient sleep the next night. Conclusions: Napping in middle-aged men and women is associated with overall less nighttime sleep in African Americans and lower sleep efficiency as measured by actigraphy, and increased BMI and central adiposity. These findings point to the importance of measuring of napping in understanding associations of sleep with cardiovascular risk. Citation: Owens JF; Buysee DJ; Hall M; Kamarck TW; Lee L; Strollo PJ; Reis SE; Matthews KA. Napping, nighttime sleep, and cardiovascular risk factors in mid-life adults. J Clin Sleep Med 2010;6(4):330-335. PMID:20726280

Light at night disrupts nocturnal rest and elevates glucocorticoids at cool color temperatures.

PubMed

Alaasam, Valentina J; Duncan, Richard; Casagrande, Stefania; Davies, Scott; Sidher, Abhijaat; Seymoure, Brett; Shen, Yantao; Zhang, Yong; Ouyang, Jenny Q

2018-05-15

Nighttime light pollution is quickly becoming a pervasive, global concern. Since the invention and proliferation of light-emitting diodes (LED), it has become common for consumers to select from a range of color temperatures of light with varying spectra. Yet, the biological impacts of these different spectra on organisms remain unclear. We tested if nighttime illumination of LEDs, at two commercially available color temperatures (3000 and 5000 K) and at ecologically relevant illumination levels affected body condition, food intake, locomotor activity, and glucocorticoid levels in zebra finches (Taeniopygia guttata). We found that individuals exposed to 5000 K light had higher rates of nighttime activity (peaking after 1 week of treatment) compared to 3000 K light and controls (no nighttime light). Birds in the 5000 K treatment group also had increased corticosterone levels from pretreatment levels compared to 3000 K and control groups but no changes in body condition or food intake. Individuals that were active during the night did not consequently decrease daytime activity. This study adds to the growing evidence that the spectrum of artificial light at night is important, and we advocate the use of nighttime lighting with warmer color temperatures of 3000 K instead of 5000 K to decrease energetic costs for avian taxa. © 2018 Wiley Periodicals, Inc.

Acute Effects of Zolpidem Extended-Release on Cognitive Performance and Sleep in Healthy Males After Repeated Nightly Use

PubMed Central

Kleykamp, Bethea A.; Griffiths, Roland R.; McCann, Una D.; Smith, Michael T.; Mintzer, Miriam Z.

2012-01-01

The extended-release formulation of zolpidem (Ambien CR®) is approved for the treatment of insomnia without a treatment duration limit. Acutely zolpidem impairs performance, and no research to date has examined whether tolerance develops to these performance impairments during nighttime awakening. The present double-blind, placebo-controlled study examined whether tolerance develops to zolpidem-induced acute performance impairment after repeated (22–30 days) nightly use. Effects of bedtime administration of zolpidem extended-release (ZOL; 12.5 mg) were tested on a battery of performance measures assessed during a forced nighttime awakening in 15 healthy male volunteers who completed overnight polysomnographic recording sessions in our laboratory at baseline and after approximately a month of at-home ZOL. As expected, bedtime ZOL administration was associated with changes in sleep architecture and impairments across all performance domains during nighttime testing (psychomotor function, attention, working memory, episodic memory, metacognition) with no residual next morning impairment. Tolerance did not develop to the observed ZOL-related impairments on any outcome. Possible evidence of acute abstinence effects following discontinuation of ZOL was observed on some performance and sleep outcomes. Overall, these findings suggest that performance is significantly impaired during nighttime awakening even after a month of nightly ZOL administration and these impairments could significantly impact safety should nighttime awakening require unimpaired functioning (e.g., driving; combat-related activities in the military). PMID:21928913

Daytime Napping, Nighttime Sleeping, and Parkinson Disease

PubMed Central

Gao, Jianjun; Huang, Xuemei; Park, Yikyung; Hollenbeck, Albert; Blair, Aaron; Schatzkin, Arthur; Chen, Honglei

2011-01-01

Preliminary evidence suggests that daytime sleepiness may predate clinical diagnosis of Parkinson disease. The authors examined daytime napping and nighttime sleeping durations, reported in 1996–1997 by 220,934 US NIH-AARP Diet and Health Study participants, in relation to Parkinson disease diagnoses at 3 clinical stages: established (cases diagnosed before 1995, n = 267), recent (1995–1999, n = 396), and prediagnostic (2000 and after, n = 770). Odds ratios and 95% confidence intervals were derived from multivariate logistic regression models. Longer daytime napping was associated with higher odds of Parkinson disease at all 3 clinical stages: the odds ratios comparing long nappers (>1 hour/day) with nonnappers were 3.9 (95% confidence interval: 2.8, 5.6) for established cases, 2.2 (95% confidence interval: 1.7, 3.0) for recent cases, and 1.5 (95% confidence interval: 1.2, 1.9) for prediagnostic cases. Further control for health status or nighttime sleeping duration attenuated the association for established cases but made little difference for recent or prediagnostic cases. In the nighttime sleeping analysis, a clear U-shaped association with Parkinson disease was observed for established cases; however, this association was attenuated markedly for recent cases and disappeared for prediagnostic cases. This study supports the notion that daytime sleepiness, but not nighttime sleeping duration, is one of the early nonmotor symptoms of Parkinson disease. PMID:21402730

Clinical trial: lansoprazole 15 or 30 mg once daily vs. placebo for treatment of frequent nighttime heartburn in self-treating subjects.

PubMed

Peura, D A; Riff, D S; Snoddy, A M; Fennerty, M B

2009-09-01

Frequent nighttime heartburn is common. Lansoprazole 15 mg is indicated for treatment of heartburn and other gastro-oesophageal reflux disease-related symptoms. To evaluate the efficacy and safety of lansoprazole in self-treating subjects with frequent nocturnal heartburn. A total of 864 subjects with heartburn on >or=2 days/week over the past month were randomized to double-blind treatment with lansoprazole 15 or 30 mg or placebo each morning. Endpoints were percentage of night times without heartburn (primary), percentage of 24-h days without heartburn and percentage of subjects without heartburn on day 1. Mean percentage of night times without heartburn was significantly greater with lansoprazole 15 mg (61.3%) or lansoprazole 30 mg (61.7%) vs. placebo (47.8%) over 14 days (P < 0.0001 vs. placebo for both doses). Percentage of 24-h days without heartburn and percentage of subjects without heartburn on day 1 were significantly greater with lansoprazole 15 or 30 mg vs. placebo. Both lansoprazole 15 and 30 mg were highly effective and well tolerated in reducing symptoms in subjects with frequent nighttime heartburn. The benefit of therapy on 24-h heartburn and nighttime heartburn on day 1 of treatment was also evident. Lansoprazole 15 mg is a suitable choice for management of frequent nighttime heartburn.

Relationships between brightness of nighttime lights and population density

NASA Astrophysics Data System (ADS)

Naizhuo, Z.

2012-12-01

Brightness of nighttime lights has been proven to be a good proxy for socioeconomic and demographic statistics. Moreover, the satellite nighttime lights data have been used to spatially disaggregate amounts of gross domestic product (GDP), fossil fuel carbon dioxide emission, and electric power consumption (Ghosh et al., 2010; Oda and Maksyutov, 2011; Zhao et al., 2012). Spatial disaggregations were performed in these previous studies based on assumed linear relationships between digital number (DN) value of pixels in the nighttime light images and socioeconomic data. However, reliability of the linear relationships was never tested due to lack of relative high-spatial-resolution (equal to or finer than 1 km × 1 km) statistical data. With the similar assumption that brightness linearly correlates to population, Bharti et al. (2011) used nighttime light data as a proxy for population density and then developed a model about seasonal fluctuations of measles in West Africa. The Oak Ridge National Laboratory used sub-national census population data and high spatial resolution remotely-sensed-images to produce LandScan population raster datasets. The LandScan population datasets have 1 km × 1 km spatial resolution which is consistent with the spatial resolution of the nighttime light images. Therefore, in this study I selected 2008 LandScan population data as baseline reference data and the contiguous United State as study area. Relationships between DN value of pixels in the 2008 Defense Meteorological Satellite Program's Operational Linescan System (DMSP-OLS) stable light image and population density were established. Results showed that an exponential function can more accurately reflect the relationship between luminosity and population density than a linear function. Additionally, a certain number of saturated pixels with DN value of 63 exist in urban core areas. If directly using the exponential function to estimate the population density for the whole brightly lit area, relatively large under-estimations would emerge in the urban core regions. Previous studies have shown that GDP, carbon dioxide emission, and electric power consumption strongly correlate to urban population (Ghosh et al., 2010; Sutton et al., 2007; Zhao et al., 2012). Thus, although this study only examined the relationships between brightness of nighttime lights and population density, the results can provide insight for the spatial disaggregations of socioeconomic data (e.g. GDP, carbon dioxide emission, and electric power consumption) using the satellite nighttime light image data. Simply distributing the socioeconomic data to each pixel in proportion to the DN value of the nighttime light images may generate relatively large errors. References Bharit N, Tatem AJ, Ferrari MJ, Grais RF, Djibo A, Grenfell BT, 2011. Science, 334:1424-1427. Ghosh T, Elvidge CD, Sutton PC, Baugh KE, Ziskin D, Tuttle BT, 2010. Energies, 3:1895-1913. Oda T, Maksyutov S, 2011. Atmospheric Chemistry and Physics, 11:543-556. Sutton PC, Elvidge CD, Ghosh T, 2007. International Journal of Ecological Economics and Statistics, 8:5-21. Zhao N, Ghosh T, Samson EL, 2012. International Journal of Remote sensing, 33:6304-6320.

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National Observatory (KPNO), part of the National Optical Astronomy Observatory (NOAO), supports the most diverse collection of astronomical observatories on Earth for nighttime optical and infrared astronomy and NOAO is the national center for ground-based nighttime astronomy in the United States and is operated

Taking into account nighttime annoyance in the calculation of the psophic index

NASA Technical Reports Server (NTRS)

Francois, J.

1981-01-01

The annoyance factor caused by air traffic noise on the residents of areas near airports is discussed. The psophic index is used to predict the level of overall annoyance suffered on the average by residents around airports. The calculation method differentiates between daytime and nighttime annoyance.

Evaluation of Nighttime Seat Belt Enforcement Demonstration Program and Identification of Characteristics of Unbelted High-Risk Drivers

DOT National Transportation Integrated Search

2018-04-01

The present study evaluated the effectiveness of a high-visibility nighttime seat belt enforcement program conducted in Maryland by measuring changes in day and night self-reported and observed seat belt use and crash outcomes. To better understand t...

Modelling night-time ecosystem respiration by a constrained source optimization method

Treesearch

Chun-Tai Lai; Gabriel Katul; John Butnor; David Ellsworth; Ram Oren

2002-01-01

One of the main challenges to quantifying ecosystem carbon budgets is properly quantifying the magnitude of night-time ecosystem respiration. Inverse Lagrangian dispersion analysis provides a promising approach to addressing such a problem when measured mean CO2 concentration profiles and nocturnal velocity statistics are available. An inverse...

Effects of rotation on the nighttime brightness of overhead highway signs utilizing high intensity sheeting.

DOT National Transportation Integrated Search

1974-01-01

As an initial step in the establishment of guidelines for the use of high intensity sheeting on overhead signs, a pilot study was made to investigate the effect of rotation on the average nighttime brightness of signs utilizing this material. Rotatio...

Epworth Sleepiness Scale may be an indicator for blood pressure profile and prevalence of coronary artery disease and cerebrovascular disease in patients with obstructive sleep apnea.

PubMed

Feng, Jing; He, Quan-ying; Zhang, Xi-long; Chen, Bao-yuan

2012-03-01

This study seeks to determine whether scores of a short questionnaire assessing subjective daytime sleepiness (Epworth Sleepiness Scale [ESS]) are associated with blood pressure (BP) level, BP profile, and prevalence of related coronary artery disease (CAD) and cerebrovascular disease (CVD) in obstructive sleep apnea (OSA) patients diagnosed by polysomnography (PSG). Twenty university hospital sleep centers in China mainland were organized by the Chinese Medical Association to participate in this study. Between January 2004 and April 2006, 2,297 consecutive patients (aged 18-85 years; 1,981 males and 316 females) referred to these centers were recruited. BP assessments were evaluated at four time points (daytime, evening, nighttime, and morning) under standardized conditions. Anthropometric measurements, medical history of hypertension, CAD, and CVD were collected. ESS score was calculated for each participant and at the night of BP assessment, nocturnal PSG was performed and subjects were classified into four groups based on the apnea-hypopnea index (AHI) from PSG as follows: control group (control, n = 213) with AHI < 5; mild sleep apnea (mild, n = 420) with AHI ≥ 5 and <15; moderate sleep apnea (moderate, n = 460) with AHI ≥ 15 and <30; and severe sleep apnea (severe, n = 1,204) with AHI ≥ 30. SPSS 11.5 software package was used for the relationships between ESS and BP profile and prevalence of CAD and CVD. ESS is correlated positively with average daytime, nighttime, evening, and morning BP before and even after controlling for confounding effects of age, sex, BMI, AHI, and nadir nocturnal oxygen saturation (before--r = 0.182, 0.326, 0.245, and 0.329, respectively, all P values < 0.001; after--r = 0.069, 0.212, 0.137, and 0.208, respectively, all P values < 0.001). In the severe group, nighttime, evening, morning average BPs (ABPs), the ratio of nighttime/daytime average BP (ratio of nighttime average BP to daytime average BP), and prevalence of hypertension, drug-resistant hypertension (R-HTN), isolated nighttime hypertension (IN-HTN), CAD, and CVD in excessive daytime sleepiness (EDS, ESS ≥ 11) subjects are higher than those in non-EDS (ESS 0-10; t/χ(2) = -8.388, -6.207, -8.607, -5.901, 12.742, 38.980, 16.343, 59.113, and 67.113, respectively; all P values < 0.05). For EDS subjects in the moderate group but not in the control and mild group, nighttime ABP and the ratio of nighttime/daytime average BP are higher (t = -2.086 and -3.815, respectively, all P values < 0.05). Linear fitting with ESS and the ratio of nighttime/daytime average BP shows a positive correlation (r(2) = 0.049, P < 0.001). In severe OSA patients with comparable AHI, EDS may identify a subset of individuals with OSA at higher risk of hypertension, R-HTN, IN-HTN, CAD, and CVD. Overall, nighttime ABP seems to be more sensitive to be influenced by EDS than other ABP parameters. Future studies should investigate the potential dose-effect relationship between EDS and hypertension and the possibility that diagnosis and treatment of EDS could aid in BP reduction and ultimately in decreased morbidity and mortality from cardiovascular and cerebrovascular complications (TMUIRB20010002 at www.clinicaltrials.gov ).

Forage and weather influence day versus nighttime cow behavior and calf weaning weights on rangeland

USDA-ARS?s Scientific Manuscript database

We determined the effects of two forage allowance levels (LOW vs. HIGH) and weather conditions on day- and nighttime movement patterns of young rangeland-raised cows. We also investigated whether calf weaning weights (WW, n = 42) were significantly related to their dams' post-calving movement patter...

Napping in College Students and Its Relationship with Nighttime Sleep

ERIC Educational Resources Information Center

Ye, Lichuan; Hutton Johnson, Stacy; Keane, Kathleen; Manasia, Michael; Gregas, Matt

2015-01-01

Objective: To examine the habit of napping and its relationship with nighttime sleep in college students. Participants: Four hundred and forty undergraduate students who responded to an anonymous online survey in April 2010. Methods: Three questions were asked to determine the frequency, length, and timing of napping during the past month. Sleep…

Napping, nighttime sleep, and cardiovascular risk factors in mid-life adults.

PubMed

Owens, Jane F; Buysse, Daniel J; Hall, Martica; Kamarck, Thomas W; Lee, Laisze; Strollo, Patrick J; Reis, Steven E; Matthews, Karen A

2010-08-15

To evaluate the relations between sleep characteristics and cardiovascular risk factors and napping behavior, and to assess whether daytime napping leads to subsequent better or worse sleep. The sample consisted of 224 (African American, Caucasian, and Asian) middle-aged men and women. Sleep measures included nine nights of actigraphy and sleep diaries, sleep questionnaires, and one night of polysomnography to measure sleep disordered breathing. More frequent napping was associated with shorter nighttime sleep duration averaged across the nine nights of actigraphy (especially among African Americans), more daytime sleepiness, more pain and fatigue by diary, and increased body mass index and waist circumference. Shorter nighttime sleep duration was associated with taking a nap during the next day and taking a nap was associated with less efficient sleep the next night. Napping in middle-aged men and women is associated with overall less nighttime sleep in African Americans and lower sleep efficiency as measured by actigraphy, and increased BMI and central adiposity. These findings point to the importance of measuring of napping in understanding associations of sleep with cardiovascular risk.

Fungal spores overwhelm biogenic organic aerosols in a midlatitudinal forest

NASA Astrophysics Data System (ADS)

Zhu, Chunmao; Kawamura, Kimitaka; Fukuda, Yasuro; Mochida, Michihiro; Iwamoto, Yoko

2016-06-01

Both primary biological aerosol particles (PBAPs) and oxidation products of biogenic volatile organic compounds (BVOCs) contribute significantly to organic aerosols (OAs) in forested regions. However, little is known about their relative importance in diurnal timescales. Here, we report biomarkers of PBAP and secondary organic aerosols (SOAs) for their diurnal variability in a temperate coniferous forest in Wakayama, Japan. Tracers of fungal spores, trehalose, arabitol and mannitol, showed significantly higher levels in nighttime than daytime (p < 0.05), resulting from the nocturnal sporulation under near-saturated relative humidity. On the contrary, BVOC oxidation products showed higher levels in daytime than nighttime, indicating substantial photochemical SOA formation. Using tracer-based methods, we estimated that fungal spores account for 45 % of organic carbon (OC) in nighttime and 22 % in daytime, whereas BVOC oxidation products account for 15 and 19 %, respectively. To our knowledge, we present for the first time highly time-resolved results that fungal spores overwhelmed BVOC oxidation products in contributing to OA especially in nighttime. This study emphasizes the importance of both PBAPs and SOAs in forming forest organic aerosols.

Spatiotemporal Evolution of the Imbalanced Regional Development in Mainland China Using Dmsp-Ols Data

NASA Astrophysics Data System (ADS)

Chen, K.; Jia, T.

2017-09-01

The Defense Meteorological Satellite Programs Operational Linescan System (DMSP-OLS) nighttime lights imagery has been widely used to monitor economic activities and regional development in recent decades. In this paper, we firstly processed the nighttime light imageries of the Mainland China from 1992 to 2013 due to the radiation or geometric errors. Secondly, by dividing the Mainland China into seven regions, we found high correlation between the sum light values and GDP of each region. Thirdly, we extracted the economic centers of each region based on their nighttime light images. Through the analysis, we found the distribution of these economic centers was relatively concentrated and the migration of these economic centers showed certain directional trend or circuitous changes, which suggested the imbalanced socio-economic development of each region. Then, we calculated the Regional Development Gini of each region using the nighttime light data, which indicated that social-economic development in South China presents great imbalance while it is relatively balanced in Southwest China. This study would benefit the macroeconomic control to regional economic development and the introduction of appropriate economic policies from the national level.

The great 2006 heat wave over California and Nevada: Signal of an increasing trend

USGS Publications Warehouse

Gershunov, A.; Cayan, D.R.; Iacobellis, S.F.

2009-01-01

Most of the great California-Nevada heat waves can be classified into primarily daytime or nighttime events depending on whether atmospheric conditions are dry or humid. A rash of nighttime-accentuated events in the last decade was punctuated by an unusually intense case in July 2006, which was the largest heat wave on record (1948-2006). Generally, there is a positive trend in heat wave activity over the entire region that is expressed most strongly and clearly in nighttime rather than daytime temperature extremes. This trend in nighttime heat wave activity has intensified markedly since the 1980s and especially since 2000. The two most recent nighttime heat waves were also strongly expressed in extreme daytime temperatures. Circulations associated with great regional heat waves advect hot air into the region. This air can be dry or moist, depending on whether a moisture source is available, causing heat waves to be expressed preferentially during day or night. A remote moisture source centered within a marine region west of Baja California has been increasing in prominence because of gradual sea surface warming and a related increase in atmospheric humidity. Adding to the very strong synoptic dynamics during the 2006 heat wave were a prolonged stream of moisture from this southwestern source and, despite the heightened humidity, an environment in which afternoon convection was suppressed, keeping cloudiness low and daytime temperatures high. The relative contributions of these factors and possible relations to global warming are discussed. ?? 2009 American Meteorological Society.

Child passenger injury risk in motor vehicle crashes: a comparison of nighttime and daytime driving by teenage and adult drivers.

PubMed

Chen, Irene G; Durbin, Dennis R; Elliott, Michael R; Senserrick, Teresa; Winston, Flaura K

2006-01-01

To examine the association between child passenger injury risk, restraint use, and crash time (day vs. night) for children in crashes of vehicles driven by teenage versus adult drivers. Cross-sectional study involving telephone interviews with insured drivers in a probability sample of 6,184 crashes involving 10,028 children. Child passengers in teen nighttime crashes had an increased injury risk and an increased risk of restraint nonuse compared with those in teen daytime crashes. This increased injury risk can be explained by differences in the age of child passengers, collision type, and child passenger's restraint status associated with time of day. In order to limit the risk of injury to child passengers driven by teens, Graduated Driver Licensing (GDL) laws should include provisions restricting nighttime driving, as well as mandates for age-appropriate restraint for child passengers. Consideration should also be given for education in child passenger safety for novice teen drivers as part of the licensing process. Results of this study can be used to support advocacy efforts by the automotive industry and others to promote nighttime driving restrictions on novice drivers. In addition, given that both driver groups were more likely to be involved in a single-vehicle collision during the night, technologies such as electronic stability control may offer opportunities for protection. Further reseach on specific circumstances of teen nighttime crashes is needed to inform industry efforts to improve visibility or vehicle operation under poor lighting conditions.

Effect of azilsartan versus candesartan on nocturnal blood pressure variation in Japanese patients with essential hypertension.

PubMed

Rakugi, Hiromi; Kario, Kazuomi; Enya, Kazuaki; Igeta, Masataka; Ikeda, Yoshinori

2013-09-01

Abnormal variations in night-time hypertension such as "non-dipping" type (< 10% decrease in nocturnal systolic blood pressure [SBP] from daytime SBP) are a risk factor for cardiovascular events independent of 24-h BP. As part of a randomized, double-blind study of azilsartan (20-40 mg once daily) and candesartan (8-12 mg once daily) in Japanese patients with essential hypertension, an exploratory analysis was performed using ambulatory BP monitoring (ABPM) at baseline and Week 14. Effects of study drugs on nocturnal BP variations according to patients' nocturnal SBP dipping status were evaluated. ABPM data were available for 273 patients treated with azilsartan and 275 with candesartan. In the dipping group (≥ 10% decrease from daytime SBP), azilsartan produced a greater reduction from baseline in daytime than in night-time SBP (- 14.1 and - 10.9 mmHg, respectively), and the change in daytime SBP was significantly greater with azilsartan than with candesartan (p = 0.0077). In the non-dipping group, azilsartan produced a greater reduction from baseline in night-time than in daytime SBP (- 20.2 and - 9.9 mmHg, respectively), and reductions in both night-time SBP (p = 0.02) and daytime SBP (p = 0.0042) were significantly greater with azilsartan than with candesartan. Once-daily azilsartan improved non-dipping night-time SBP to a greater extent than candesartan in Japanese patients with grade I-II essential hypertension.

Predictors of noise annoyance in noisy and quiet urban streets.

PubMed

Paunović, Katarina; Jakovljević, Branko; Belojević, Goran

2009-06-01

Although noise annoyance is a major public health problem in urban areas, there is a lack of published data on predictors for noise annoyance in acoustically different urban environments. The aim of the study was to assess the predictive value of various factors on noise annoyance in noisy and quiet urban streets. Equivalent noise levels [Leq (dBA)] were measured during day, evening and night times in all of the streets of a central Belgrade municipality. Based on 24-hour noise levels, the streets were denoted as noisy (24-hour Leq over 65 dBA), or quiet (24-hour Leq under 55 dBA). A cross-sectional study was performed on 1954 adult residents (768 men and 1186 women), aged 18-80 years. Noise annoyance was estimated using a self-report five-graded scale. In both areas, two multivariate logistic regression models were fitted: the first one with nighttime noise indicators and the other one with parameters for 24-hour noise exposure. In noisy streets, the relevant predictors of high annoyance were: the orientation of living room/bedroom toward the street, noise annoyance at workplace, and noise sensitivity. Significant acoustical factors for high noise annoyance were: nighttime noise level [OR=1.02, 95%CI=1.00-1.04 (per decibel)], nighttime heavy traffic [OR=1.01, 95%CI=1.00-1.02 (per vehicle)]; or day-evening-night noise level (Lden) [OR=1.03, 95%CI=1.00-1.07 (per decibel)]. In quiet streets, the significant predictors were: noise sensitivity, the time spent at home daily, light vehicles at nighttime or heavy vehicles at daytime. Our study identified subjective noise sensitivity as a common annoyance predictor, regardless of noise exposure. Noise levels were important indicators of annoyance only in noisy streets, both for nighttime and 24-hour exposure. We propose that noise sensitivity is the most relevant personal trait for future studies and that nighttime noise levels might be as good as Lden in predicting annoyance in noisy urban areas.

Prevalence and impact of respiratory symptoms in a population of patients with COPD in Latin America: The LASSYC observational study.

PubMed

Miravitlles, Marc; Menezes, Ana; López Varela, Maria Victorina; Casas, Alejandro; Ugalde, Luis; Ramirez-Venegas, Alejandra; Mendoza, Laura; López, Ana; Wehrmeister, Fernando C; Surmont, Filip; Montes de Oca, Maria

2018-01-01

To analyse the relationship between symptoms at different times during the 24-hour day and outcomes in COPD. Observational cross-sectional study in a patients from 7 Latin American countries. The frequency of symptoms in the morning, at night and during the day was explored by means of standardised and validated questionnaires, and the relationship between symptoms and exacerbations and quality of life were investigated. 734 patients (59.6% male, mean age 69.5 years, mean FEV 1 50% predicted normal) were recruited. The most frequent symptoms during the day were dyspnea (75% of patients, of which 94% mild-moderate) and cough (72.2%, of which 93.4% mild-moderate). Highly symptomatic patients had a greater impairment in FEV 1 , more exacerbations and worse scores in COPD assessment test (CAT) and Body Mass Index, Obstruction, Dyspnoea and Exacerbations (BODEx) index (all p < 0.001). Morning symptoms were more frequent than night-time symptoms, particularly cough and dyspnoea (morning: 50.1% and 45.7%; night-time: 33.2% and 24.4%, respectively), and mostly rated as mild or moderate. Patients with morning or night-time symptoms presented with worse severity of daytime symptoms. There was a strong correlation between intensity of daytime with morning or night-time symptoms, as well as with CAT score (r = 0.715; p < 0.001), but a weak correlation with FEV 1 (r = -0.205; p < 0.001). Morning symptoms were more frequent than night-time symptoms, and having either morning and/or night-time symptoms was associated with worse severity of daytime symptoms. Increased symptoms were strongly associated with worse quality of life and more frequent exacerbations, but weakly associated with airflow limitation. NCT02789540. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tracking Dynamic Changes and Monitoring Socioeconomic Parameters in Algeria Between 1993 and 2012, Using Nighttime Light Remote Sensing

NASA Astrophysics Data System (ADS)

Faouzi, B.; Washaya, P.

2017-09-01

This paper is based on using DMSP-OLS data from satellites nighttime light observations to detect both sources of light emissions in Algeria from human settlement areas and gas flaring from oil-extraction and natural gas production. We used the time series of data from DMSP-OLS images to examine the spatial and temporal characteristics of urban development in 48 Algerian provinces from 1993 to 2012. A systematic nighttime light calibration method was used to improve the consistency and comparability of the DSMPOSL images and then a separation is made between light detected from human settlements and light detected from gas flaring in order to allow us to study human settlements without other light emissions and then assess the suitability of using DMSP data in southern Algeria and its ability to monitor gas flaring. Linear regression methods were developed to identify the dynamic change of nighttime light and estimated its growth directions at pixel level. This work is the first to use nighttime light observations to detect and monitor the growth of human settlements in North Africa. In this study, we made use of DMSP-OLS data as a return ticket to the years of crises and we found the most affected provinces during that period. The DMSP-OLS data proved to be an index of growth in the economy during the period of stability in Algeria expressed by positive dynamic changes in the lighted area in all Algerian provinces. We used NTL data as an alternative to annual growth indexes for each province, which are unavailable, and its help as a monitoring system for socioeconomic parameters to fill the gap of data availability. We also proposed nighttime light remote sensing data as a useful tool to control and reduce CO2 emissions in Algeria's petroleum sector.

Determinants of day-night difference in blood pressure, a comparison with determinants of daytime and night-time blood pressure.

PubMed

Musameh, M D; Nelson, C P; Gracey, J; Tobin, M; Tomaszewski, M; Samani, N J

2017-01-01

Blunted day-night difference in blood pressure (BP) is an independent cardiovascular risk factor, although there is limited information on determinants of diurnal variation in BP. We investigated determinants of day-night difference in systolic (SBP) and diastolic (DBP) BP and how these compared with determinants of daytime and night-time SBP and DBP. We analysed the association of mean daytime, mean night-time and mean day-night difference (defined as (mean daytime-mean night-time)/mean daytime) in SBP and DBP with clinical, lifestyle and biochemical parameters from 1562 adult individuals (mean age 38.6) from 509 nuclear families recruited in the GRAPHIC Study. We estimated the heritability of the various BP phenotypes. In multivariate analysis, there were significant associations of age, sex, markers of adiposity (body mass index and waist-hip ratio), plasma lipids (total and low-density lipoprotein cholesterol and triglycerides), serum uric acid, alcohol intake and current smoking status on daytime or night-time SBP and/or DBP. Of these, only age (P=4.7 × 10 -5 ), total cholesterol (P=0.002), plasma triglycerides (P=0.006) and current smoking (P=3.8 × 10 -9 ) associated with day-night difference in SBP, and age (P=0.001), plasma triglyceride (P=2.2 × 10 -5 ) and current smoking (3.8 × 10 -4 ) associated with day-night difference in DBP. 24-h, daytime and night-time SBP and DBP showed substantial heritability (ranging from 18-43%). In contrast day-night difference in SBP showed a lower heritability (13%) while heritability of day-night difference in DBP was not significant. These data suggest that specific clinical, lifestyle and biochemical factors contribute to inter-individual variation in daytime, night-time and day-night differences in SBP and DBP. Variation in day-night differences in BP is largely non-genetic.

Determinants of day–night difference in blood pressure, a comparison with determinants of daytime and night-time blood pressure

PubMed Central

Musameh, M D; Nelson, C P; Gracey, J; Tobin, M; Tomaszewski, M; Samani, N J

2017-01-01

Blunted day–night difference in blood pressure (BP) is an independent cardiovascular risk factor, although there is limited information on determinants of diurnal variation in BP. We investigated determinants of day–night difference in systolic (SBP) and diastolic (DBP) BP and how these compared with determinants of daytime and night-time SBP and DBP. We analysed the association of mean daytime, mean night-time and mean day–night difference (defined as (mean daytime−mean night-time)/mean daytime) in SBP and DBP with clinical, lifestyle and biochemical parameters from 1562 adult individuals (mean age 38.6) from 509 nuclear families recruited in the GRAPHIC Study. We estimated the heritability of the various BP phenotypes. In multivariate analysis, there were significant associations of age, sex, markers of adiposity (body mass index and waist–hip ratio), plasma lipids (total and low-density lipoprotein cholesterol and triglycerides), serum uric acid, alcohol intake and current smoking status on daytime or night-time SBP and/or DBP. Of these, only age (P=4.7 × 10−5), total cholesterol (P=0.002), plasma triglycerides (P=0.006) and current smoking (P=3.8 × 10−9) associated with day–night difference in SBP, and age (P=0.001), plasma triglyceride (P=2.2 × 10−5) and current smoking (3.8 × 10−4) associated with day–night difference in DBP. 24-h, daytime and night-time SBP and DBP showed substantial heritability (ranging from 18–43%). In contrast day–night difference in SBP showed a lower heritability (13%) while heritability of day–night difference in DBP was not significant. These data suggest that specific clinical, lifestyle and biochemical factors contribute to inter-individual variation in daytime, night-time and day–night differences in SBP and DBP. Variation in day–night differences in BP is largely non-genetic. PMID:26984683

Associations of night-time road traffic noise with carotid intima-media thickness and blood pressure: The Whitehall II and SABRE study cohorts.

PubMed

Halonen, Jaana I; Dehbi, Hakim-Moulay; Hansell, Anna L; Gulliver, John; Fecht, Daniela; Blangiardo, Marta; Kelly, Frank J; Chaturvedi, Nish; Kivimäki, Mika; Tonne, Cathryn

2017-01-01

Road traffic noise has been linked to increased risk of stroke, for which hypertension and carotid intima-media thickness (cIMT) are risk factors. A link between traffic noise and hypertension has been established, but there are few studies on blood pressure and no studies on cIMT. To examine cross-sectional associations for long-term exposure to night-time noise with cIMT, systolic blood pressure (SBP), diastolic blood pressure (DBP) and hypertension. The study population consisted of 2592 adults from the Whitehall II and SABRE cohort studies living within Greater London who had cIMT, SBP and DBP measured. Exposure to night-time road traffic noise (A-weighted dB, referred to as dBA) was estimated at each participant's residential postcode centroid. Mean night-time road noise levels were 52dBA (SD=4). In the pooled analysis adjusted for cohort, sex, age, ethnicity, marital status, smoking, area-level deprivation and NOx there was a 9.1μm (95% CI: -7.1, 25.2) increase in cIMT in association with 10dBA increase in night-time noise. Analyses by noise categories of 55-60dBA (16.2μm, 95% CI: -8.7, 41.2), and >60dBA (21.2μm, 95% CI: -2.5, 44.9) vs. <55dBA were also positive but non-significant, expect among those not using antihypertensive medication and exposed to >60dBA vs. <55dBA (32.6μm, 95% CI: 6.2, 59.0). Associations for SBP, DPB and hypertension were close to null. After adjustments, including for air pollution, the association between night-time road traffic noise and cIMT was only observed among non-medication users but associations with blood pressure and hypertension were largely null. Copyright © 2016 Elsevier Ltd. All rights reserved.

Spatial clusters of daytime sleepiness and association with nighttime noise levels in a Swiss general population (GeoHypnoLaus).

PubMed

Joost, Stéphane; Haba-Rubio, José; Himsl, Rebecca; Vollenweider, Peter; Preisig, Martin; Waeber, Gérard; Marques-Vidal, Pedro; Heinzer, Raphaël; Guessous, Idris

2018-05-31

Daytime sleepiness is highly prevalent in the general adult population and has been linked to an increased risk of workplace and vehicle accidents, lower professional performance and poorer health. Despite the established relationship between noise and daytime sleepiness, little research has explored the individual-level spatial distribution of noise-related sleep disturbances. We assessed the spatial dependence of daytime sleepiness and tested whether clusters of individuals exhibiting higher daytime sleepiness were characterized by higher nocturnal noise levels than other clusters. Population-based cross-sectional study, in the city of Lausanne, Switzerland. Sleepiness was measured using the Epworth Sleepiness Scale (ESS) for 3697 georeferenced individuals from the CoLaus|PsyCoLaus cohort (period = 2009-2012). We used the sonBASE georeferenced database produced by the Swiss Federal Office for the Environment to characterize nighttime road traffic noise exposure throughout the city. We used the GeoDa software program to calculate the Getis-Ord G i * statistics for unadjusted and adjusted ESS in order to detect spatial clusters of high and low ESS values. Modeled nighttime noise exposure from road and rail traffic was compared across ESS clusters. Daytime sleepiness was not randomly distributed and showed a significant spatial dependence. The median nighttime traffic noise exposure was significantly different across the three ESS Getis cluster classes (p < 0.001). The mean nighttime noise exposure in the high ESS cluster class was 47.6, dB(A) 5.2 dB(A) higher than in low clusters (p < 0.001) and 2.1 dB(A) higher than in the neutral class (p < 0.001). These associations were independent of major potential confounders including body mass index and neighborhood income level. Clusters of higher daytime sleepiness in adults are associated with higher median nighttime noise levels. The identification of these clusters can guide tailored public health interventions. Copyright © 2018 The Authors. Published by Elsevier GmbH.. All rights reserved.

The development of a patient-reported outcome measure for assessing nighttime symptoms of chronic obstructive pulmonary disease.

PubMed

Hareendran, Asha; Palsgrove, Andrew C; Mocarski, Michelle; Schaefer, Michael L; Setyawan, Juliana; Carson, Robyn; Make, Barry

2013-06-25

The assessment of symptoms of chronic obstructive pulmonary disease (COPD) is important for monitoring and managing the disease and for evaluating outcomes of interventions. COPD patients experience symptoms during the day and night, and symptoms experienced at night often disturb sleep. The aim of this paper is to describe methods used to develop a patient-reported outcome (PRO) instrument for evaluating nighttime symptoms of COPD, and to document evidence for the content validity of the instrument. Literature review and clinician interviews were conducted to inform discussion guides to explore patients' nighttime COPD symptom experience. Data from focus groups with COPD patients was used to develop a conceptual framework and the content of a new PRO instrument. Patient understanding of the new instrument was assessed via cognitive interviews with COPD patients. The literature review confirmed that there is no instrument with evidence of content validity currently available to assess nighttime symptoms of COPD. Additionally, the literature review and clinician interviews suggested the need to understand patients' experience of specific symptoms in order to evaluate nighttime symptoms of COPD. Analyses of patient focus group data (N = 27) supported saturation of concepts and aided in development of a conceptual framework. Items were generated using patients' terminology to collect data on concepts in the framework including the occurrence and severity of COPD symptoms, use of rescue medication at night, and nocturnal awakening. Response options were chosen to reflect concepts that were salient to patients. Subsequent cognitive interviewing with ten COPD patients demonstrated that the items, response options, recall period, and instructions were understandable, relevant, and interpreted as intended. A new PRO instrument, the Nighttime Symptoms of COPD Instrument (NiSCI), was developed with documented evidence of content validity. The NiSCI is ready for empirical testing, including item reduction and evaluation of psychometric properties.

Compositional and surface characterization of HULIS by UV-Vis, FTIR, NMR and XPS: Wintertime study in Northern India

NASA Astrophysics Data System (ADS)

Kumar, Varun; Goel, Anubha; Rajput, Prashant

2017-09-01

This study (first attempt) characterizes HULIS (Humic Like Substances) in wintertime aerosols (n = 12 during day and nighttime each) from Indo-Gangetic Plain (IGP, at Kanpur) by using various state-of-the art techniques such as UV-VIS, FTIR, 1H NMR and XPS. Based on UV-Vis analysis the absorption coefficient at 365 nm (babs-365) of HULIS was found to average at 13.6 and 28.8 Mm-1 during day and nighttime, respectively. Relatively high babs-365 of HULIS during the nighttime is attributed to influence of fog-processing. However, the power fit of UV-Vis spectrum provided near similar AAE (absorption Angstrom exponent) value of HULIS centering at 4.9 ± 1.4 and 5.1 ± 1.3 during daytime and nighttime, respectively. FTIR spectra and its double derivative revealed the presence of various functional groups viz. alcohols, ketones aldehydes, carboxylic acids as well as unsaturated and saturated carbon bonds. 1H NMR spectroscopy was applied to quantify relative percentage of various types of hydrogen atoms contained in HULIS, whereas XPS technique provided information on surface composition and oxidation states of various elements present. A significantly high abundance of H‒C‒O group has been observed in HULIS (based on 1H NMR); 41.4± 2.7% and 30.9± 2.4% in day and nighttime, respectively. However, aromatic protons (Ar-H) were higher in nighttime samples (19.3± 1.8%) as compared to that in daytime samples (7.5 ± 1.9). XPS studies revealed presence of various species on the surface of HULIS samples. Carbon existed in 7 different chemical states while total nitrogen and sulfur exhibited 3 and 2 different oxidation states (respectively) on the surface of HULIS. This study reports structural information and absorption properties of HULIS which has implications to their role as cloud condensation nuclei and atmospheric direct radiative forcing.

Nighttime Supplemental LED Inter-lighting Improves Growth and Yield of Single-Truss Tomatoes by Enhancing Photosynthesis in Both Winter and Summer.

PubMed

Tewolde, Fasil T; Lu, Na; Shiina, Kouta; Maruo, Toru; Takagaki, Michiko; Kozai, Toyoki; Yamori, Wataru

2016-01-01

Greenhouses with sophisticated environmental control systems, or so-called plant factories with solar light, enable growers to achieve high yields of produce with desirable qualities. In a greenhouse crop with high planting density, low photosynthetic photon flux density (PPFD) at the lower leaves tends to limit plant growth, especially in the winter when the solar altitude and PPFD at the canopy are low and day length is shorter than in summer. Therefore, providing supplemental lighting to the lower canopy can increase year-round productivity. However, supplemental lighting can be expensive. In some places, the cost of electricity is lower at night, but the effect of using supplemental light at night has not yet been examined. In this study, we examined the effects of supplemental LED inter-lighting (LED inter-lighting hereafter) during the daytime or nighttime on photosynthesis, growth, and yield of single-truss tomato plants both in winter and summer. We used LED inter-lighting modules with combined red and blue light to illuminate lower leaves right after the first anthesis. The PPFD of this light was 165 μmol m(-2) s(-1) measured at 10 cm from the LED module. LED inter-lighting was provided from 4:00 am to 4:00 pm for the daytime treatments and from 10:00 pm to 10:00 am for the nighttime treatments. Plants exposed only to solar light were used as controls. Daytime LED inter-lighting increased the photosynthetic capacity of middle and lower canopy leaves, which significantly increased yield by 27% in winter; however, photosynthetic capacity and yield were not significantly increased during summer. Nighttime LED inter-lighting increased photosynthetic capacity in both winter and summer, and yield increased by 24% in winter and 12% in summer. In addition, nighttime LED inter-lighting in winter significantly increased the total soluble solids and ascorbic acid content of the tomato fruits, by 20 and 25%, respectively. Use of nighttime LED inter-lighting was also more cost-effective than daytime inter-lighting. Thus, nighttime LED inter-lighting can effectively improve tomato plant growth and yield with lower energy cost compared with daytime both in summer and winter.

Nighttime Supplemental LED Inter-lighting Improves Growth and Yield of Single-Truss Tomatoes by Enhancing Photosynthesis in Both Winter and Summer

PubMed Central

Tewolde, Fasil T.; Lu, Na; Shiina, Kouta; Maruo, Toru; Takagaki, Michiko; Kozai, Toyoki; Yamori, Wataru

2016-01-01

Greenhouses with sophisticated environmental control systems, or so-called plant factories with solar light, enable growers to achieve high yields of produce with desirable qualities. In a greenhouse crop with high planting density, low photosynthetic photon flux density (PPFD) at the lower leaves tends to limit plant growth, especially in the winter when the solar altitude and PPFD at the canopy are low and day length is shorter than in summer. Therefore, providing supplemental lighting to the lower canopy can increase year-round productivity. However, supplemental lighting can be expensive. In some places, the cost of electricity is lower at night, but the effect of using supplemental light at night has not yet been examined. In this study, we examined the effects of supplemental LED inter-lighting (LED inter-lighting hereafter) during the daytime or nighttime on photosynthesis, growth, and yield of single-truss tomato plants both in winter and summer. We used LED inter-lighting modules with combined red and blue light to illuminate lower leaves right after the first anthesis. The PPFD of this light was 165 μmol m-2 s-1 measured at 10 cm from the LED module. LED inter-lighting was provided from 4:00 am to 4:00 pm for the daytime treatments and from 10:00 pm to 10:00 am for the nighttime treatments. Plants exposed only to solar light were used as controls. Daytime LED inter-lighting increased the photosynthetic capacity of middle and lower canopy leaves, which significantly increased yield by 27% in winter; however, photosynthetic capacity and yield were not significantly increased during summer. Nighttime LED inter-lighting increased photosynthetic capacity in both winter and summer, and yield increased by 24% in winter and 12% in summer. In addition, nighttime LED inter-lighting in winter significantly increased the total soluble solids and ascorbic acid content of the tomato fruits, by 20 and 25%, respectively. Use of nighttime LED inter-lighting was also more cost-effective than daytime inter-lighting. Thus, nighttime LED inter-lighting can effectively improve tomato plant growth and yield with lower energy cost compared with daytime both in summer and winter. PMID:27092163

Prevalence of and impact of pantoprazole on nocturnal heartburn and associated sleep complaints in patients with erosive esophagitis.

PubMed

Kindt, S; Imschoot, J; Tack, J

2011-11-01

Studies in the United States have revealed that gastroesophageal reflux disease (GERD) patients often suffer from nocturnal symptoms, sleep disturbance, and impaired quality of life. In a large subset of patients, these symptoms persist in spite of acid suppressive therapy. The aim of the present study was to assess the prevalence of heartburn and associated sleep complaints and the response to standard medical therapy with pantoprazole in primary and secondary care esophagitis patients in Belgium. Questionnaires were provided to consecutive patients presenting to primary and secondary care physicians with esophagitis. The questionnaire evaluated the presence of typical reflux symptoms, alarm symptoms, risk factors, and sleep quality impairment as a result of reflux episodes. Results are shown as mean ± standard deviation and compared by Student's t-test or chi-square test. A total of 4061 primary and 5261 secondary care patients (50% female, mean age 53 ± 0.2 years, body mass index of 25.7 ± 0.1 kg/m(2) ) were recruited. Eighty-four percent of patients reported sleep disturbance attributable to nighttime reflux, including typical nighttime supine reflux symptoms (72%), difficulties to fall asleep (39%), waking up during the night (45%), morning fatigue (35%), and reflux symptoms when waking up in the morning (47%). Mild, moderate, or severe nighttime heartburn were reported by, respectively, 30, 35, and 12%, and these numbers were 26, 28, and 6% for nighttime regurgitation. Alcohol (19%), smoking (22%), higher esophagitis grades (grades 2, 3, and 4 in, respectively, 31, 7, and, 7%), alarm symptoms (27%), and more severe heartburn and regurgitation during daytime were all significantly associated with all dimensions of sleep disturbance (P < 0.0001). Obesity was only related to symptoms in supine position and when waking up (P < 0.0001). After 1.4 ± 0.0 months of treatment with pantoprazole, any sleep disturbance had improved in more than 75% of patients, with resolution of nighttime heartburn and regurgitation in, respectively, 75 and 83%. The majority of patients presenting with reflux symptoms and esophagitis in primary or secondary care experience nighttime heartburn and regurgitation, and sleep disturbance by nighttime symptoms is present in 84%. Smoking, alcohol use, higher grades of esophagitis, more severe typical reflux symptoms during daytime, and the presence of alarm symptoms are risk factors for GERD-related sleep disturbance. On standard therapy with pantoprazole, nighttime symptoms improved in more than 75%. These observations support a direct relationship between GERD and sleep disturbance. © 2011 Copyright the Authors. Journal compilation © 2011, Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

Thermal analysis of fractures at Cerberus Fossae, Mars: Detection of air convection in the porous debris apron

NASA Astrophysics Data System (ADS)

Antoine, R.; Lopez, T.; Baratoux, D.; Rabinowicz, M.; Kurita, K.

2011-08-01

This study investigates the cause of high nighttime temperatures within Cerberus Fossae, a system of fractures affecting the Central Elysium Planitia. The inner parts (walls and floor) of the fractures are up to 40 K warmer than the surrounding plains. However, several temperature profiles exhibit a local temperature minima occurring in the central part of the fractures. We examined first the influence of cooling efficiency at night in the case of a strong reduction of the sky proportion induced by the fracture's geometry. However, the lack of correlation between temperature and sky proportion, calculated from extracted Mars Orbiter Laser Altimeter (MOLA) profiles argues against this hypothesis. Albedo variations were considered but appear to be limited within the fractures, and are generally not correlated with the temperatures. Variations of the thermal properties of bedrocks exposures, debris aprons and sand dunes inferred from high-resolution images do not either correlate with temperature variations within the fractures. As none of these factors taken alone, or combined, can satisfactorily explain the temperature variations within and near the fracture, we suggest that geothermal heat transported by air convection within the porous debris aprons may contribute to explain high temperatures at night and the local minima on the fracture floor. The conditions for the occurrence of the suggested phenomenon and the consequences on the surface temperature are numerically explored. A conservative geothermal gradient of 20 mW/m 2 was used in the simulations, this value being consistent with either inferred lithosphere elastic thicknesses below the shield volcanoes of the Tharsis dome or values predicted from numerical simulations of the thermal evolution of Mars. The model results indicate that temperature differences of 10-20 K between the central and upper parts of the fracture are explained in the case of high Darcy velocities which require high permeability values (5 × 10 -6 m 2). The presence of coarse material composing the debris aprons may explain why this key criteria was met in the context of Cerberus Fossae.

ESO unveils an amazing, interactive, 360-degree panoramic view of the entire night sky

NASA Astrophysics Data System (ADS)

2009-09-01

The first of three images of ESO's GigaGalaxy Zoom project - a new magnificent 800-million-pixel panorama of the entire sky as seen from ESO's observing sites in Chile - has just been released online. The project allows stargazers to explore and experience the Universe as it is seen with the unaided eye from the darkest and best viewing locations in the world. This 360-degree panoramic image, covering the entire celestial sphere, reveals the cosmic landscape that surrounds our tiny blue planet. This gorgeous starscape serves as the first of three extremely high-resolution images featured in the GigaGalaxy Zoom project, launched by ESO within the framework of the International Year of Astronomy 2009 (IYA2009). GigaGalaxy Zoom features a web tool that allows users to take a breathtaking dive into our Milky Way. With this tool users can learn more about many different and exciting objects in the image, such as multicoloured nebulae and exploding stars, just by clicking on them. In this way, the project seeks to link the sky we can all see with the deep, "hidden" cosmos that astronomers study on a daily basis. The wonderful quality of the images is a testament to the splendour of the night sky at ESO's sites in Chile, which are the most productive astronomical observatories in the world. The plane of our Milky Way Galaxy, which we see edge-on from our perspective on Earth, cuts a luminous swath across the image. The projection used in GigaGalaxy Zoom place the viewer in front of our Galaxy with the Galactic Plane running horizontally through the image - almost as if we were looking at the Milky Way from the outside. From this vantage point, the general components of our spiral galaxy come clearly into view, including its disc, marbled with both dark and glowing nebulae, which harbours bright, young stars, as well as the Galaxy's central bulge and its satellite galaxies. The painstaking production of this image came about as a collaboration between ESO, the renowned French writer and astrophotographer Serge Brunier and his fellow Frenchman Frédéric Tapissier. Brunier spent several weeks during the period between August 2008 and February 2009 capturing the sky, mostly from ESO observatories at La Silla and Paranal in Chile. In order to cover the full Milky Way, Brunier also made a week-long trip to La Palma, one of the Canary Islands, to photograph the northern skies [1]. Once the raw photographs were in hand, image processing by Tapissier and ESO experts helped to convey accurately the night sky as our eyes behold it [2]. The resulting image, now available on GigaGalaxy Zoom, is composed of almost 300 fields each individually captured by Brunier four times, adding up to nearly 1200 photos that encompass the entire night sky. "I wanted to show a sky that everyone can relate to - with its constellations, its thousands of stars, with names familiar since childhood, its myths shared by all civilisations since Homo became Sapiens," says Brunier. "The image was therefore made as man sees it, with a regular digital camera under the dark skies in the Atacama Desert and on La Palma." As photographing extended over several months, objects from the Solar System came and went through the star fields, with bright planets such as Venus and Jupiter. A brilliant, emerald-green comet also flew by, although spotting it among a background of tens of millions of stars will be difficult (but rewarding). Overall, the creators of the GigaGalaxy Zoom project hope that these tremendous efforts in bringing the night sky as observed under the best conditions on the planet to stargazers everywhere will inspire awe for the beautiful, immense Universe that we live in. "The vision of the IYA2009 is to help people rediscover their place in the Universe through the day- and night-time sky, and this is exactly what the GigaGalaxy Zoom project is all about," says project coordinator Henri Boffin. The second dramatic GigaGalaxy Zoom image will be revealed next week, on 21 September 2009. Notes [1] During his quest, Brunier used a Nikon D3 digital camera. The apparent motion of the sky caused by Earth's rotation was corrected for using a small, precise equatorial mount moving in the opposite direction, which made a whole circle in 23 hours 56 minutes around the Earth's axis of rotation. Each photo required a six-minute exposure, for a total exposure time of more than 120 hours. [2] The data processing, using software called Autopano Pro Giga, took great care in respecting the colours and "texture" of the Milky Way. Frédéric Tapissier needed about 340 computing hours on a powerful PC to complete the task. More information As part of the IYA2009, ESO is participating in several remarkable outreach activities, in line with its world-leading rank in the field of astronomy. ESO is hosting the IYA2009 Secretariat for the International Astronomical Union, which coordinates the Year globally. ESO is one of the Organisational Associates of IYA2009, and was also closely involved in the resolution submitted to the United Nations (UN) by Italy, which led to the UN's 62nd General Assembly proclaiming 2009 the International Year of Astronomy. In addition to a wide array of activities planned both at the local and international level, ESO is leading three of the twelve global Cornerstone Projects. ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 42-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become "the world's biggest eye on the sky". Serge Brunier is a French journalist, photographer and writer who specialises in popularising astronomy. He is a regular contributor to Science & Vie magazine, and to the France Info radio station. He has written numerous popular astronomy books, translated into over ten languages, and is a prize-winning photographer, who has captured images of solar eclipses from the most amazing places in the world. A life-long quest for the best skies in the world led him to Chile. This whole sky panorama was presented from 25 August till 13 September 2009 in the exhibition "Un ciel pour la planète" (A sky for the planet) in the Atrium of the Monte-Carlo Casino, Monaco. With a giant print of 12 times 6 metres, the exhibition was under the Patronage of The Prince Albert II of Monaco, and showed with images and videos the making of this unique ESO project.

Geographical analysis of equatorial plasma bubbles by GPS and nightglow measurements

NASA Astrophysics Data System (ADS)

Nade, D. P.; Shetti, D. J.; Sharma, A. K.; Taori, A.; Chavan, G. A.; Patil, P. T.; Ghodpage, R. N.; Gurav, O. B.; Nikte, S. S.

2015-11-01

This work about the zonal drift velocity and signature of equatorial plasma bubbles (EPBs) by measurements of global positioning system (GPS) receiver and all sky imager (ASI) operating in India, at the low latitude region. The optical and radio observations have been made from Kolhapur (16.8° N, 74.2° E) and Hyderabad (17.37°N, 78.48°E), respectively. The zonal drift velocity of EPBs has estimated using images of nightglow OI 630.0 nm emission recorded by ASI at Kolhapur. The measurements of total electron content (TEC) using the GPS have carried from the nearby station, Hyderabad. When depletions occurred about 00:37 h (IST) in TEC, the EPBs were found to occur about 5:30 h in optical data of OI 630.0 nm emission. This work focuses on simultaneous measurements of TEC and intensity of OI 630.0 nm emissions for EPBs during nighttime. The occurrence period of EPBs in TEC and OI 630.0 nm has found to be different. To study this difference, the zonal drift velocity of EPBs has established. The averaged eastward velocity of EPBs was found to be 138 m/s. The calculated values of zonal drift velocities are well correlated with that of the empirical model values. This work may be helpful in finding the growth of EPBs over low latitude.

Aurora Borealis, A Painting by Frederic Edwin Church

NASA Astrophysics Data System (ADS)

Love, J. J.

2015-12-01

This year marks the sesquicentennial anniversary of the end of the American Civil War. In 1865, the same year as the War's end, the great American landscape artist, Frederic Edwin Church, unveiled Aurora Borealis, a painting that depicts a fantastic, far-northern place, an auroral arch stretched across a quiet night-time sky, above dark mountains and a frozen sea. Church was born in Connecticut, lived in New York, and traveled to Labrador; he would have often seen the northern lights. Church might have also been influenced by the spectacular displays of aurora that were caused by some unusually intense magnetic storms in 1859. Aurora Borealis can certainly be interpreted in terms of 19th-century romanticism, scientific philosophy, and Arctic missions of exploration, all subjects of interest to Church. As with so many of his paintings, Church's meticulous attention to detail in Aurora Borealis reveals his deep admiration of nature. But his depiction of auroral light is a curious and possibly intentional departure from natural verisimilitude. Some art historians have suggested that Church painted Aurora Borealis as a subdued tribute to the end of the Civil War, with the drapery of auroral light forming an abstract representation of the American flag. If so, then colors of the flag have been unfurled across a cold and barren landscape, not in extravagant celebration, but in somber recognition of the reality of post-war desolation and an uncertain future.

Geomagnetically conjugate observation of plasma bubbles and thermospheric neutral winds at low latitudes

NASA Astrophysics Data System (ADS)

Fukushima, D.; Shiokawa, K.; Otsuka, Y.; Nishioka, M.; Kubota, M.; Tsugawa, T.; Nagatsuma, T.; Komonjinda, S.; Yatini, C. Y.

2015-03-01

This is the first paper that reports simultaneous observations of zonal drift of plasma bubbles and the thermospheric neutral winds at geomagnetically conjugate points in both hemispheres. The plasma bubbles were observed in the 630 nm nighttime airglow images taken by using highly sensitive all-sky airglow imagers at Kototabang, Indonesia (geomagnetic latitude (MLAT): 10.0°S), and Chiang Mai, Thailand (MLAT: 8.9°N), which are nearly geomagnetically conjugate stations, for 7 h from 13 to 20 UT (from 20 to 03 LT) on 5 April 2011. The bubbles continuously propagated eastward with velocities of 100-125 m/s. The 630 nm images at Chiang Mai and those mapped to the conjugate point of Kototabang fit very well, which indicates that the observed plasma bubbles were geomagnetically connected. The eastward thermospheric neutral winds measured by two Fabry-Perot interferometers were 70-130 m/s at Kototabang and 50-90 m/s at Chiang Mai. We compared the observed plasma bubble drift velocity with the velocity calculated from the observed neutral winds and the model conductivity, to investigate the F region dynamo contribution to the bubble drift velocity. The estimated drift velocities were 60-90% of the observed velocities of the plasma bubbles, suggesting that most of the plasma bubble velocity can be explained by the F region dynamo effect.

Philippine Astronomy Convention 2009 Abstract: IYA 2009

NASA Astrophysics Data System (ADS)

Divinagracia, P. P.

2009-03-01

The International Year of Astronomy 2009 is a global effort initiated by the International Astronomical Union (IAU) and the United Nations Educational, Scientific and Cultural Organization (UNESCO) to help the citizens of the world rediscover their place in the Universe through the day and nighttime sky and, thereby, engage a personal sense of wonder and discovery. The vision of the IYA celebration is for everyone to realize the impact of astronomy and other fundamental sciences on our daily lives, and understand how scientific knowledge can contribute to a more equitable and peaceful society. Various global projects were initiated to help achieve the goals of the IYA 2009. An opening ceremony was held last January 15 to 16, 2009 at the UNESCO Headquarters at Paris, France to mark the beginning of the IYA celebrations. Attendance for the said ceremony was by invitation only. In the Philippines, Dr. Cynthia Celebre, Chief of the Space Sciences and Astronomy Section of the Philippine Atmospheric, Geophysical and Astronomical Services Administration, and the Single Point of Contact in the Philippines for the IYA, and I, as the student representative of the Philippines, were invited to attend the opening ceremony. We also participated in a symposium with the theme "The Role of Astronomy in Society and Culture" which was also held at the UNESCO Headquarters at Paris, France last January 19 to 23 this year.

Frost and leaf-size gradients in forests: global patterns and experimental evidence.

PubMed

Lusk, Christopher H; Clearwater, Michael J; Laughlin, Daniel C; Harrison, Sandy P; Prentice, Iain Colin; Nordenstahl, Marisa; Smith, Benjamin

2018-05-16

Explanations of leaf size variation commonly focus on water availability, yet leaf size also varies with latitude and elevation in environments where water is not strongly limiting. We provide the first conclusive test of a prediction of leaf energy balance theory that may explain this pattern: large leaves are more vulnerable to night-time chilling, because their thick boundary layers impede convective exchange with the surrounding air. Seedlings of 15 New Zealand evergreens spanning 12-fold variation in leaf width were exposed to clear night skies, and leaf temperatures were measured with thermocouples. We then used a global dataset to assess several climate variables as predictors of leaf size in forest assemblages. Leaf minus air temperature was strongly correlated with leaf width, ranging from -0.9 to -3.2°C in the smallest- and largest-leaved species, respectively. Mean annual temperature and frost-free period were good predictors of evergreen angiosperm leaf size in forest assemblages, but no climate variable predicted deciduous leaf size. Although winter deciduousness makes large leaves possible in strongly seasonal climates, large-leaved evergreens are largely confined to frost-free climates because of their susceptibility to radiative cooling. Evergreen leaf size data can therefore be used to enhance vegetation models, and to infer palaeotemperatures from fossil leaf assemblages. © 2018 The Authors New Phytologist © 2018 New Phytologist Trust.

Air flow analysis in the upper Río Negro Valley (Argentina)

NASA Astrophysics Data System (ADS)

Cogliati, M. G.; Mazzeo, N. A.

2006-06-01

The so called Upper Río Negro Valley in Argentina is one of the most important fruit and vegetable production regions of the country. It comprises the lower valleys of the Limay and Neuquén rivers and the upper Negro river valley. Out of the 41,671 cultivated hectares, 84.6% are cultivated with fruit trees, especially apple, pear and stone fruit trees. Late frosts occurring when trees are sensitive to low temperatures have a significant impact on the regional production. This study presents an analysis of air flow characteristics in the Upper Río Negro Valley and its relationship with ambient air flow. To such effect, observations made when synoptic-scale weather patterns were favorable for radiative frosts (light wind and clear sky) or nocturnal temperature inversion in the lower layer were used. In the Negro river valley, both wind channeling and downward horizontal momentum transport from ambient wind were observed; in nighttime, very light wind events occurred, possibly associated with drainage winds from the nearby higher levels of the barda. In the Neuquén river valley, the prevailing effect appeared to be forced channeling, consistent with the results obtained in valleys where the synoptic scale wind crossed the axis of the valley. In the Limay river valley, the flow was observed to blow parallel to the longitudinal valley axis, possibly influenced by pressure gradient and forced channeling.

Development of a model performance-based sign sheeting specification based on the evaluation of nighttime traffic signs using legibility and eye-tracker data : data and analyses.

DOT National Transportation Integrated Search

2010-09-01

This report presents data and technical analyses for Texas Department of Transportation Project 0-5235. This : project focused on the evaluation of traffic sign sheeting performance in terms of meeting the nighttime : driver needs. The goal was to de...

Sleep Habits and Nighttime Texting among Adolescents

ERIC Educational Resources Information Center

Garmy, Pernilla; Ward, Teresa M.

2018-01-01

The aim of this study was to examine sleep habits (i.e., bedtimes and rising times) and their association with nighttime text messaging in 15- to 17-year-old adolescents. This cross-sectional study analyzed data from a web-based survey of adolescent students attending secondary schools in southern Sweden (N = 278, 50% female). Less than 8 hr of…

Dissonance between Parent-Selected Bedtimes and Young Children's Circadian Physiology Influences Nighttime Settling Difficulties

ERIC Educational Resources Information Center

LeBourgeois, Monique K.; Wright, Kenneth P., Jr.; LeBourgeois, Hannah B.; Jenni, Oskar G.

2013-01-01

Nighttime settling difficulties (i.e., bedtime resistance, sleep-onset delay) occur in about 25% of young children and are associated with attentional, behavioral, and emotional problems. We examined whether the timing of internal (endogenous) circadian melatonin phase (i.e., dim light melatonin onset; DLMO) and its relationship with…

Environmental Assessment: Anti-Terrorism/Force Protection at Grand Forks Air Force Base, North Dakota

DTIC Science & Technology

2003-09-01

OUTDOOR NOISE SOURCES NOISE LEVEL (dBA) COMMON INDOOR NOISE LEVELS COMMON OUTDOOR NOISE LEVELS Gas Lawn Mower at 3 ft. Diesel Truck at 50 ft. Noise...Urban Daytime Gas Lawn Mower at 100 ft. Commercial Area Heavy Traffic at 300 ft. Quiet Urban Daytime Quiet Urban Nighttime Quiet Rural Nighttime Quiet

Environmental Assessment: Military Housing Privatization Initiative at Scott Air Force Base, Illinois

DTIC Science & Technology

2005-09-01

OUTDOOR NOISE SOURCES NOISE LEVEL (dBA) COMMON INDOOR NOISE LEVELS COMMON OUTDOOR NOISE LEVELS Gas Lawn Mower at 3 ft. Diesel Truck at 50 ft. Noise...Urban Daytime Gas Lawn Mower at 100 ft. Commercial Area Heavy Traffic at 300 ft. Quiet Urban Daytime Quiet Urban Nighttime Quiet Rural Nighttime Quiet

a Cross-Sectional Study on Insomnia among Japanese Adult Women in Relation to Night-Time Road Traffic Noise

NASA Astrophysics Data System (ADS)

Kageyama, T.; Kabuto, M.; Nitta, N.; Kurokawa, Y.; Taira, K.; Suzuki, S.; Takemoto, T.

1997-08-01

In an effort to determine the contribution of night-time road traffic noise to insomnia in the general population, 3600 adult Japanese women living in urban residential areas were surveyed. Living near a road with a heavy traffic volume is one of the risk factors for insomnia. The risk for insomnia in the zones 0-20 m from the main roads increased linearly with the night-time traffic volume. This suggests that road traffic noise raises the sound level in bedrooms in such zones, and consequently the prevalence rate of insomnia among the residents, and that noise-induced insomnia is an important public health problem, at least in highly urbanized areas.

Nighttime Ozone Chemical Equilibrium in the Mesopause Region

NASA Astrophysics Data System (ADS)

Kulikov, M. Yu.; Belikovich, M. V.; Grygalashvyly, M.; Sonnemann, G. R.; Ermakova, T. S.; Nechaev, A. A.; Feigin, A. M.

2018-03-01

We examine the applicability of the assumption that nighttime ozone is in photochemical equilibrium. The analysis is based on calculations with a 3-D chemical transport model. These data are used to determine the ratio of correct (calculated) O3 density to its equilibrium value for the conditions of the nighttime mesosphere depending on the altitude, latitude, and month in the annual cycle. The results obtained demonstrate that the retrieval of O and H distributions using the assumption of photochemical ozone equilibrium may lead to a significant error below 81-87 km depending on season. Possible modifications of the currently used approach that allow improving the quality of retrieval of O and H mesospheric distributions from satellite-based observations are discussed.

A natural-color mapping for single-band night-time image based on FPGA

NASA Astrophysics Data System (ADS)

Wang, Yilun; Qian, Yunsheng

2018-01-01

A natural-color mapping for single-band night-time image method based on FPGA can transmit the color of the reference image to single-band night-time image, which is consistent with human visual habits and can help observers identify the target. This paper introduces the processing of the natural-color mapping algorithm based on FPGA. Firstly, the image can be transformed based on histogram equalization, and the intensity features and standard deviation features of reference image are stored in SRAM. Then, the real-time digital images' intensity features and standard deviation features are calculated by FPGA. At last, FPGA completes the color mapping through matching pixels between images using the features in luminance channel.

Urban Spatial Pattern and Interaction based on Analysis of Nighttime Remote Sensing Data and Geo-social Media Information

NASA Astrophysics Data System (ADS)

Ratnasari, Nila; Dwi Candra, Erika; Herdianta Saputra, Defa; Putra Perdana, Aji

2016-11-01

Urban development in Indonesia significantly incerasing in line with rapid development of infrastructure, utility, and transportation network. Recently, people live depend on lights at night and social media and these two aspects can depicted urban spatial pattern and interaction. This research used nighttime remote sensing data with the VIIRS (Visible Infrared Imaging Radiometer Suite) day-night band detects lights, gas flares, auroras, and wildfires. Geo-social media information derived from twitter data gave big picture on spatial interaction from the geospatial footprint. Combined both data produced comprehensive urban spatial pattern and interaction in general for Indonesian territory. The result is shown as a preliminary study of integrating nighttime remote sensing data and geospatial footprint from twitter data.

The effect of moonlight on observation of cloud cover at night, and application to cloud climatology

NASA Technical Reports Server (NTRS)

Hahn, Carole J.; Warren, Stephen G.; London, Julius

1995-01-01

Ten years of nighttime weather observations from the Northern Hemisphere in December were classified according to the illuminance of moonlight or twilight on the cloud tops, and a threshold level of illuminance was determined, above which the clouds are apparently detected adequately. This threshold corresponds to light from a full moon at an elevation angle of 6 deg, light from a partial moon at higher elevation, or twilight from the sun less than 9 deg bvelow the horizon. It permits the use of about 38% of the observations made with the sun below the horizon. The computed diurnal cycles of total cloud cover are altered considerably when this moonlight criterion is imposed. Maximum cloud cover over much of the ocean is now found to be at night or in the morning, whereas computations obtained without benefit of the moonlight criterion, as in our published atlases, showed the time of maximum to be noon or early afternoon in many regions. The diurnal cycles of total cloud cover we obtain are compared with those of the International Satellite Cloud Climatology Project (ISCCP) for a few regions; they are generally in better agreement if the moonlight criterion is imposed on the surface observations. Using the moonlight criterion, we have analyzed 10 years (1982-91) of surface weather observations over land and ocean, worldwide, for total cloud cover and for the frequency of occurrence of clear sky, fog, and precipitation. The global average cloud cover (average of day and night) is about 2% higher if the moonlight criterion is imposed than if all observations are used. The difference is greater in winter than in summer, because of the fewer hours of darkness in summer. The amplitude of the annual cycle of total cloud cover over the Arctic Ocean and at the South Pole is diminished by a few percent when the moonlight criterion is imposed. The average cloud cover for 1982-91 is found to be 55% for Northern Hemisphere land, 53% for Southern Hemisphere land, 66% for Northern Hemisphere ocean, and 70% for Southern Hemisphere ocean, giving a global average of 64%. The global average for daytime is 64.6%; for nighttime 63.3%.

Evaluation of MODIS Land Surface Temperature with In Situ Snow Surface Temperature from CREST-SAFE

NASA Astrophysics Data System (ADS)

Perez Diaz, C. L.; Lakhankar, T.; Romanov, P.; Munoz, J.; Khanbilvardi, R.; Yu, Y.

2016-12-01

This paper presents the procedure and results of a temperature-based validation approach for the Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST) product provided by the National Aeronautics and Space Administration (NASA) Terra and Aqua Earth Observing System satellites using in situ LST observations recorded at the Cooperative Remote Sensing Science and Technology Center - Snow Analysis and Field Experiment (CREST-SAFE) during the years of 2013 (January-April) and 2014 (February-April). A total of 314 day and night clear-sky thermal images, acquired by the Terra and Aqua satellites, were processed and compared to ground-truth data from CREST-SAFE with a frequency of one measurement every 3 min. Additionally, this investigation incorporated supplementary analyses using meteorological CREST-SAFE in situ variables (i.e. wind speed, cloud cover, incoming solar radiation) to study their effects on in situ snow surface temperature (T-skin) and T-air. Furthermore, a single pixel (1km2) and several spatially averaged pixels were used for satellite LST validation by increasing the MODIS window size to 5x5, 9x9, and 25x25 windows for comparison. Several trends in the MODIS LST data were observed, including the underestimation of daytime values and nighttime values. Results indicate that, although all the data sets (Terra and Aqua, diurnal and nocturnal) showed high correlation with ground measurements, day values yielded slightly higher accuracy ( 1°C), both suggesting that MODIS LST retrievals are reliable for similar land cover classes and atmospheric conditions. Results from the CREST-SAFE in situ variables' analyses indicate that T-air is commonly higher than T-skin, and that a lack of cloud cover results in: lower T-skin and higher T-air minus T-skin difference (T-diff). Additionally, the study revealed that T-diff is inversely proportional to cloud cover, wind speed, and incoming solar radiation. Increasing the MODIS window size showed an overestimation of in situ LST and some improvement in the daytime Terra and nighttime Aqua biases, with the highest accuracy achieved with the 5x5 window. A comparison between MODIS emmisivity from bands 31, 32, and in situ emissivity showed that emissivity errors (Relative error = -.003) were insignificant.

Google Sky: A Digital View of the Night Sky

NASA Astrophysics Data System (ADS)

Connolly, A. Scranton, R.; Ornduff, T.

2008-11-01

From its inception Astronomy has been a visual science, from careful observations of the sky using the naked eye, to the use of telescopes and photographs to map the distribution of stars and galaxies, to the current era of digital cameras that can image the sky over many decades of the electromagnetic spectrum. Sky in Google Earth (http://earth.google.com) and Google Sky (http://www.google.com/sky) continue this tradition, providing an intuitive visual interface to some of the largest astronomical imaging surveys of the sky. Streaming multi-color imagery, catalogs, time domain data, as well as annotating interesting astronomical sources and events with placemarks, podcasts and videos, Sky provides a panchromatic view of the universe accessible to anyone with a computer. Beyond a simple exploration of the sky Google Sky enables users to create and share content with others around the world. With an open interface available on Linux, Mac OS X and Windows, and translations of the content into over 20 different languages we present Sky as the embodiment of a virtual telescope for discovery and sharing the excitement of astronomy and science as a whole.

Analysis of Human Activities in Nature Reserves Based on Nighttime Light Remote Sensing and Microblogging Data - by the Case of National Nature Reserves in Jiangxi Province

NASA Astrophysics Data System (ADS)

Shi, F.; Li, X.; Xu, H.

2017-09-01

The study used the mainstream social media in china - Sina microblogging data combined with nighttime light remote sensing and various geographical data to reveal the pattern of human activities and light pollution of the Jiangxi Provincial National Nature Reserves. Firstly, we performed statistical analysis based on both functional areas and km-grid from the perspective of space and time, and selected the key areas for in-depth study. Secondly, the relationship between microblogging data and nighttime light remote sensing, population, GDP, road coverage, road distance and road type in nature reserves was analyzed by Spearman correlation coefficient method, so the distribution pattern and influencing factors of the microblogging data were explored. Thirdly, a region where the luminance value was greater than 0.2 was defined as a light region. We evaluated the management status by analyzing the distribution of microblogging data in both light area and non-light area. Final results showed that in all nature reserves, the top three were the Lushan Nature Reserve, the Jinggangshan Nature Reserve, the Taohongling National Nature Reserve of Sikas both on the total number and density of microblogging ; microblogging had a significant correlation with nighttime light remote sensing , the GDP, population, road and other factors; the distribution of microblogging near roads in protected area followed power laws; luminous radiance of Lushan Nature Reserve was the highest, with 43 percent of region was light at night; analysis combining nighttime light remote sensing with microblogging data reflected the status of management of nature reserves.

Effectiveness of graduated driver licensing in reducing motor vehicle crashes.

PubMed

Foss, R D; Evenson, K R

1999-01-01

To determine whether graduated driver licensing (GDL) systems and nighttime curfews reduce motor vehicle crashes, fatalities, or injuries among young drivers. We used Cochrane Collaboration search strategies to locate studies of graduated licensing or night driving restrictions. Studies were selected if they examined the effects of either (1) a comprehensive graduated driver licensing system including well-integrated components, or (2) nighttime driving restrictions/curfews that could affect young persons' nighttime driving, on a clearly defined crash or injury outcome. Seven studies met inclusion criteria. Two independent studies of the New Zealand graduated licensing program found a sustained 7%-8% reduction in teen driver crash injuries attributable to the program. No other full graduated licensing system has been evaluated to date. Four studies of either a general curfew or a nighttime driving restriction for teens, a key element of graduated licensing, found substantial crash reductions during restricted hours, with 23%-25% lower crash injury and fatality rates for curfews beginning prior to midnight. One study found no change in late night crashes before and after a 1 a.m.-6 a.m. night driving restriction took effect. The logic and empirical bases for graduated licensing are sound. Moreover, there is evidence that one central element, a restriction on nighttime driving by novices, reduces young driver crashes. However, a definitive conclusion about the effectiveness of GDL systems for reducing motor vehicle crashes or crash-related injuries must await examination of other GDL systems. This should be possible within the next few years, as several states and Canadian provinces have recently enacted GDL programs.

Artificial Outdoor Nighttime Lights Associate with Altered Sleep Behavior in the American General Population.

PubMed

Ohayon, Maurice M; Milesi, Cristina

2016-06-01

Our study aims to explore the associations between outdoor nighttime lights (ONL) and sleep patterns in the human population. Cross-sectional telephone study of a representative sample of the general US population age 18 y or older. 19,136 noninstitutionalized individuals (participation rate: 83.2%) were interviewed by telephone. The Sleep-EVAL expert system administered questions on life and sleeping habits; health; sleep, mental and organic disorders (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision; International Classification of Sleep Disorders, Second Edition; International Classification of Diseases, 10(th) Edition). Individuals were geolocated by longitude and latitude. Outdoor nighttime light measurements were obtained from the Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS), with nighttime passes taking place between 19:30 and 22:30 local time. Light data were correlated precisely to the geolocation of each participant of the general population sample. Living in areas with greater ONL was associated with delayed bedtime (P < 0.0001) and wake up time (P < 0.0001), shorter sleep duration (P < 0.01), and increased daytime sleepiness (P < 0.0001). Living in areas with greater ONL also increased the dissatisfaction with sleep quantity and quality (P < 0.0001) and the likelihood of having a diagnostic profile congruent with a circadian rhythm disorder (P < 0.0001). Although they improve the overall safety of people and traffic, nighttime lights in our streets and cities are clearly linked with modifications in human sleep behaviors and also impinge on the daytime functioning of individuals living in areas with greater ONL. © 2016 Associated Professional Sleep Societies, LLC.

VIIRS S-NPP Nighttime DNB Spectral Response Function (SRF): The At-launch Characteristics and How the SRF Changes with Time Due to Tungsten Oxides Chromaticity

NASA Astrophysics Data System (ADS)

Guenther, B.; Lei, N.; Moeller, C.

2015-12-01

The VIIRS Day-Night Band (DNB) is designed with 3 gain stages: Low (LGS), Mid (MGS) and High (HGS) to span bright daytime to moonlit night earth scene signal levels. The published at-launch DNB relative spectral response (RSR) is based upon the LGS spectral measurements, since it was well measured in the pre-launch test program and the LGS can be calibrated by the on-board solar diffuser (MGS and HGS saturate on the SD). The LGS RSR however does not fully represent the spectral characteristics of nighttime DNB data from the MGS and HGS. Nighttime data users who apply the detailed DNB spectral characteristics in their analyses should use modulated RSR appropriate to the MGS and HGS observations. The RSR modulation is due to spectral darkening of the 4 mirrors of the S-NPP VIIRS telescope, which were contaminated with tungsten oxides in fabrication. These tungsten oxides are 'in family' with transition lenses on eyeglasses that darken when exposed to sunlight but do not recover when VIIRS goes into darkness because VIIRS in space is in a vacuum (transition lenses require atmospheric oxygen to recover). The on-going mirror darkening has caused a time-dependent shift in DNB RSR towards blue wavelengths. This presentation will provide access to the correct RSR to use for S-NPP DNB nighttime data over the mission time on-orbit. The changes in characteristics will be described in engineering terms to facilitate clear user understanding of how to handle RSR for nighttime observations over the mission lifetime.

Daytime symptoms of restless legs syndrome--clinical characteristics and rotigotine effectiveness.

PubMed

Takahashi, Masayoshi; Ikeda, Junji; Tomida, Takayuki; Hirata, Koichi; Hattori, Nobutaka; Inoue, Yuichi

2015-07-01

To elucidate the prevalence and clinical characteristics of daytime restless legs syndrome (RLS) among patients with idiopathic RLS and investigate the effectiveness of rotigotine for daytime RLS. In 256 enrolled RLS patients, we investigated factors associated with the presence of RLS symptoms throughout the day. We also assessed the duration of daytime RLS symptoms at hourly intervals, time of initial symptom onset during the day, and associations between duration of daytime and nighttime RLS symptoms. In addition, we compared changes in duration and frequency of RLS symptoms during daytime and nighttime after randomly assigning patients to a 13-week treatment with rotigotine, a dopamine agonist patch with 24-hour action, or placebo. Eighty-one (31.6%) patients had daytime RLS symptoms. Only the International Restless Legs Syndrome Study Group rating scale total score was significantly associated with the presence of daytime RLS symptoms (p < 0.01) on multiple logistic regression analysis. Daytime RLS symptom onset was at 6 a.m. in 44.4% of patients; symptom duration increased significantly toward nighttime. There was a significant positive association between duration of daytime and nighttime RLS symptoms (p < 0.0001) and a greater statistically significant reduction of daytime RLS symptom duration with rotigotine treatment than with placebo (p = 0.03). Daytime symptoms are frequent in patients with RLS and may be associated with increased severity of the disorder and prolonged nighttime RLS symptoms. Rotigotine could become an important treatment choice for daytime symptoms. Copyright © 2015 Elsevier B.V. All rights reserved.

High-Latitude Scintillation Morphology, Alaskan Sector

DTIC Science & Technology

1979-10-01

region. Localized nighttime scintillation enhancements within the scin - tillation boundary have been associated with active auroral arcs. This list...thus ideally located for measuring scin - tillation phenomena associated with the nighttime auroral oval. The Wideband satellite orbit is such that...1000 UT). The region of enhanced phase scin - tillation between 0952 and 0955 is associated with a narrow region of enhanced energetic particle

Postmodern Investigations: The Case of Christopher Boone in "The Curious Incident of the Dog in the Night-Time"

ERIC Educational Resources Information Center

Ciocia, Stefania

2009-01-01

Mark Haddon's "The Curious Incident of the Dog in the Night-Time", the first novel to be published simultaneously for the UK adult and children's market, exemplifies the phenomenon of crossover literature better perhaps than the "Harry Potter" series, whose appeal to a dual-aged audience had caught the publishing industry by…

An example of nighttime drying in the Santa Ana mountains

Treesearch

Michael A. Fosberg; Mark J. Schroeder

1965-01-01

Humidity patterns near the 500- to 1,000-meter level on California's coastal mountains often show an anomolous decrease in the moisture content at night and early morning. A study in the Santa Ana mountains suggests that nighttime downslope winds provide the most satisfactory explanation for the decrease in moisture because of their effect on the marine layer....

Forest ecosystem respiration estimated from eddy covariance and chamber measurements under high turbulence and substantial tree mortality from bark beetles

Treesearch

Heather N. Speckman; John M. Frank; John B. Bradford; Brianna L. Miles; William J. Massman; William J. Parton; Michael G. Ryan

2015-01-01

Eddy covariance nighttime fluxes are uncertain due to potential measurement biases. Many studies report eddy covariance nighttime flux lower than flux from extrapolated chamber measurements, despite corrections for low turbulence. We compared eddy covariance and chamber estimates of ecosystem respiration at the GLEES Ameriflux site over seven growing seasons under high...

Waves in Airglow

NASA Image and Video Library

2017-12-08

In April 2012, waves in Earth’s “airglow” spread across the nighttime skies of northern Texas like ripples in a pond. In this case, the waves were provoked by a massive thunderstorm. Airglow is a layer of nighttime light emissions caused by chemical reactions high in Earth’s atmosphere. A variety of reactions involving oxygen, sodium, ozone and nitrogen result in the production of a very faint amount of light. In fact, it’s approximately one billion times fainter than sunlight (~10-11 to 10-9 W·cm-2· sr-1). This chemiluminescence is similar to the chemical reactions that light up a glow stick or glow-in-the-dark silly putty. The “day-night band,” of the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP satellite captured these glowing ripples in the night sky on April 15, 2012 (top image). The day-night band detects lights over a range of wavelengths from green to near-infrared and uses highly sensitive electronics to observe low light signals. (The absolute minimum signals detectable are at the levels of nightglow emission.) The lower image shows the thunderstorm as observed by a thermal infrared band on VIIRS. This thermal band, which is sensitive only to heat emissions (cold clouds appear white), is not sensitive to the subtle visible-light wave structures seen by the day-night band. Technically speaking, airglow occurs at all times. During the day it is called “dayglow,” at twilight “twilightglow,” and at night “nightglow.” There are slightly different processes taking place in each case, but in the image above the source of light is nightglow. The strongest nightglow emissions are mostly constrained to a relatively thin layer of atmosphere between 85 and 95 kilometers (53 and 60 miles) above the Earth’s surface. Little emission occurs below this layer since there’s a higher concentration of molecules, allowing for dissipation of chemical energy via collisions rather than light production. Likewise, little emission occurs above that layer because the atmospheric density is so tenuous that there are too few light-emitting reactions to yield an appreciable amount of light. Suomi NPP is in orbit around Earth at 834 kilometers (about 518 miles), well above the nightglow layer. The day-night band imagery therefore contains signals from the direction upward emission of the nightglow layer and the reflection of the downward nightglow emissions by clouds and the Earth’s surface. The presence of these nightglow waves is a graphic visualization of the usually unseen energy transfer processes that occur continuously between the lower and upper atmosphere. While nightglow is a well-known phenomenon, it’s not typically considered by Earth-viewing meteorological sensors. In fact, scientists were surprised at Suomi NPP’s ability to detect it. During the satellite’s check-out procedure, this unanticipated source of visible light was thought to indicate a problem with the sensor until scientists realized that what they were seeing was the faintest of light in the darkness of night. NASA Earth Observatory image by Jesse Allen and Robert Simmon, using VIIRS Day-Night Band data from the Suomi National Polar-orbiting Partnership. Suomi NPP is the result of a partnership between NASA, the National Oceanic and Atmospheric Administration, and the Department of Defense. Caption by Aries Keck and Steve Miller. Instrument: Suomi NPP - VIIRS Credit: NASA Earth Observatory Click here to view all of the Earth at Night 2012 images Click here to read more about this image NASA image use policy. NASA Goddard Space

Nested large-eddy simulations of nighttime shear-instability waves and transient warming in a steep valley

NASA Astrophysics Data System (ADS)

Zhou, Bowen; Chow, Fotini

2012-11-01

This numerical study investigates the nighttime flow dynamics in a steep valley. The Owens Valley in California is highly complex, and represents a challenging terrain for large-eddy simulations (LES). To ensure a faithful representation of the nighttime atmospheric boundary layer (ABL), realistic external boundary conditions are provided through grid nesting. The model obtains initial and lateral boundary conditions from reanalysis data, and bottom boundary conditions from a land-surface model. We demonstrate the ability to extend a mesoscale model to LES resolutions through a systematic grid-nesting framework, achieving accurate simulations of the stable ABL over complex terrain. Nighttime cold-air flow was channeled through a gap on the valley sidewall. The resulting katabatic current induced a cross-valley flow. Directional shear against the down-valley flow in the lower layers of the valley led to breaking Kelvin-Helmholtz waves at the interface, which is captured only on the LES grid. Later that night, the flow transitioned from down-slope to down-valley near the western sidewall, leading to a transient warming episode. Simulation results are verified against field observations and reveal good spatial and temporal precision. Supported by NSF grant ATM-0645784.

Comparison of Observations of Sporadic-E Layers in the Nighttime and Daytime Mid-Latitude Ionosphere

NASA Technical Reports Server (NTRS)

Pfaff, R.; Freudenreich, H.; Rowland, D.; Klenzing, J.; Clemmons, J.; Larsen, M.; Kudeki, E.; Franke, S.; Urbina, J.; Bullett, T.

2012-01-01

A comparison of numerous rocket experiments to investigate mid-latitude sporadic-E layers is presented. Electric field and plasma density data gathered on sounding rockets launched in the presence of sporadic-E layers and QP radar echoes reveal a complex electrodynamics including both DC parameters and plasma waves detected over a large range of scales. We show both DC and wave electric fields and discuss their relationship to intense sporadic-E layers in both nighttime and daytime conditions. Where available, neutral wind observations provide the complete electrodynamic picture revealing an essential source of free energy that both sets up the layers and drives them unstable. Electric field data from the nighttime experiments reveal the presence of km-scale waves as well as well-defined packets of broadband (10's of meters to meters) irregularities. What is surprising is that in both the nighttime and daytime experiments, neither the large scale nor short scale waves appear to be distinctly organized by the sporadic-E density layer itself. The observations are discussed in the context of current theories regarding sporadic-E layer generation and quasi-periodic echoes.

Investigation of ionospheric scintillation at UKM station, Malaysia during low solar activity

NASA Astrophysics Data System (ADS)

Seif, Aramesh; Abdullah, Mardina; Marie Hasbi, Alina; Zou, Yuhua

2012-12-01

In this paper the investigation of the occurrence of ionospheric scintillation with S4≥0.2 was conducted by using a dual-frequency GISTM (GPS Ionospheric Scintillation and TEC monitor) at Universiti Kebangsaan Malaysia station, Malaysia (2.55°N, 101.46°E; geomagnetic: 7.39°S, 173.63°E) between September 2009 and December 2010. The study shows that significant nighttime amplitude scintillation event with 0.4≤S4<0.6 mainly occurred in the months of March, September and October, while significant daytime amplitude scintillation activity took place in November and December with 0.3≤S4<0.5. Moreover, nighttime amplitude scintillation observed at UKM station always occurred with phase scintillations, total electron content (TEC) depletions, rate of change of TEC (ROT) fluctuations and the enhancement of rate of TEC index (ROTI). Nevertheless, during daytime amplitude scintillation, TEC depletions and ROT fluctuations were much weaker than those that occurred during nighttime and this may be caused by small scale irregularities in the E region, called sporadic-E (Es), while the occurrences of nighttime amplitude scintillation maybe caused by the ionospheric irregularities in the F region.

Polarization of 'water-skies' above arctic open waters: how polynyas in the ice-cover can be visually detected from a distance.

PubMed

Hegedüs, Ramón; Akesson, Susanne; Horváth, Gábor

2007-01-01

The foggy sky above a white ice-cover and a dark water surface (permanent polynya or temporary lead) is white and dark gray, phenomena called the 'ice-sky' and the 'water-sky,' respectively. Captains of icebreaker ships used to search for not-directly-visible open waters remotely on the basis of the water sky. Animals depending on open waters in the Arctic region may also detect not-directly-visible waters from a distance by means of the water sky. Since the polarization of ice-skies and water-skies has not, to our knowledge, been studied before, we measured the polarization patterns of water-skies above polynyas in the arctic ice-cover during the Beringia 2005 Swedish polar research expedition to the North Pole region. We show that there are statistically significant differences in the angle of polarization between the water-sky and the ice-sky. This polarization phenomenon could help biological and man-made sensors to detect open waters not directly visible from a distance. However, the threshold of polarization-based detection would be rather low, because the degree of linear polarization of light radiated by water-skies and ice-skies is not higher than 10%.

Automated cloud screening of AVHRR imagery using split-and-merge clustering

NASA Technical Reports Server (NTRS)

Gallaudet, Timothy C.; Simpson, James J.

1991-01-01

Previous methods to segment clouds from ocean in AVHRR imagery have shown varying degrees of success, with nighttime approaches being the most limited. An improved method of automatic image segmentation, the principal component transformation split-and-merge clustering (PCTSMC) algorithm, is presented and applied to cloud screening of both nighttime and daytime AVHRR data. The method combines spectral differencing, the principal component transformation, and split-and-merge clustering to sample objectively the natural classes in the data. This segmentation method is then augmented by supervised classification techniques to screen clouds from the imagery. Comparisons with other nighttime methods demonstrate its improved capability in this application. The sensitivity of the method to clustering parameters is presented; the results show that the method is insensitive to the split-and-merge thresholds.

Non-thermal distribution of O(1D) atoms in the night-time thermosphere

NASA Technical Reports Server (NTRS)

Yee, Jeng-Hwa

1988-01-01

The 6300 A O(1D-3P) emission has been used for many years to remotely monitor the thermospheric temperature from the Doppler width of its line profile. The O(1D) atoms in the nighttime thermosphere are initially produced by the dissociative recombination of O2(+) ions with kinetic energy much greater than the thermal energy of the ambient neutrals. The validity of the technique to monitor neutral ambient temperature by measuring O(1D) 6300 A emission depends on the degree of thermalization of the O(1D) atoms. The object of this study is to calculate the velocity distribution of the O(1D) atoms and to examine the effect of nonthermal distribution on the nighttime thermospheric neutral temperature determined.

The new education frontier: clinical teaching at night.

PubMed

Hanson, Joshua T; Pierce, Read G; Dhaliwal, Gurpreet

2014-02-01

Regulations that restrict resident work hours and call for increased resident supervision have increased attending physician presence in the hospital during the nighttime. The resulting increased interactions between attendings and trainees provide an important opportunity and obligation to enhance the quality of learning that takes place in the hospital between 6 PM and 8 AM. Nighttime education should be transformed in a way that maintains clinical productivity for both attending and resident physicians, integrates high-quality teaching and curricula, and achieves a balance between patient safety and resident autonomy. Direct observation of trainees, instruction in communication, and modeling of cost-efficient medical practice may be more feasible during the night than during daytime hours. To realize the potential of this educational opportunity, training programs should develop skilled nighttime educators and establish metrics to define success.

Infrared Sky Imager (IRSI) Instrument Handbook

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morris, Victor R.

2016-04-01

The Infrared Sky Imager (IRSI) deployed at the Atmospheric Radiation Measurement (ARM) Climate Research Facility is a Solmirus Corp. All Sky Infrared Visible Analyzer. The IRSI is an automatic, continuously operating, digital imaging and software system designed to capture hemispheric sky images and provide time series retrievals of fractional sky cover during both the day and night. The instrument provides diurnal, radiometrically calibrated sky imagery in the mid-infrared atmospheric window and imagery in the visible wavelengths for cloud retrievals during daylight hours. The software automatically identifies cloudy and clear regions at user-defined intervals and calculates fractional sky cover, providing amore » real-time display of sky conditions.« less

Global surface-based cloud observation for ISCCP

NASA Technical Reports Server (NTRS)

1994-01-01

Visual observations of cloud cover are hindered at night due to inadequate illumination of the clouds. This usually leads to an underestimation of the average cloud cover at night, especially for the amounts of middle and high clouds, in climatologies on surface observations. The diurnal cycles of cloud amounts, if based on all the surface observations, are therefore in error, but they can be obtained more accurately if the nighttime observations are screened to select those made under sufficient moonlight. Ten years of nighttime weather observations from the northern hemisphere in December were classified according to the illuminance of moonlight or twilight on the cloud tops, and a threshold level of illuminance was determined, above which the clouds are apparently detected adequately. This threshold corresponds to light from a full moon at an elevation angle of 6 degrees or from a partial moon at higher elevation, or twilight from the sun less than 9 degrees below the horizon. It permits the use of about 38% of the observations made with the sun below the horizon. The computed diurnal cycles of total cloud cover are altered considerably when this moonlight criterion is imposed. Maximum cloud cover over much of the ocean is now found to be at night or in the morning, whereas computations obtained without benefit of the moonlight criterion, as in our published atlases, showed the time of maximum to be noon or early afternoon in many regions. Cloud cover is greater at night than during the day over the open oceans far from the continents, particularly in summer. However, near noon maxima are still evident in the coastal regions, so that the global annual average oceanic cloud cover is still slightly greater during the day than at night, by 0.3%. Over land, where daytime maxima are still obtained but with reduced amplitude, average cloud cover is 3.3% greater during the daytime. The diurnal cycles of total cloud cover we obtain are compared with those of ISCCP for a few regions; they are generally in better agreement if the moonlight criterion is imposed on the surface observations. Using the moonlight criterion, we have analyzed ten years (1982-1991) of surface weather observations over land and ocean, worldwide, for total cloud cover and for the frequency of occurrence of clear sky, fog and precipitation The global average cloud cover (average of day and night) is about 2% higher if we impose the moonlight criterion than if we use all observations. The difference is greater in winter than in summer, because of the fewer hours of darkness in the summer. The amplitude of the annual cycle of total cloud cover over the Arctic Ocean and at the South Pole is diminished by a few percent when the moonlight criterion is imposed. The average cloud cover for 1982-1991 is found to be 55% for northern hemisphere land, 53% for southern hemisphere land, 66% for northern hemisphere ocean, and 70% for southern hemisphere ocean, giving a global average of 64%. The global average for daytime is 64.6% for nighttime 63.3%.

Watching the Detectives: Mark Haddon's "The Curious Incident of the Dog in the Night-Time" and Kevin Brooks' "Martyn Pig"

ERIC Educational Resources Information Center

Gilbert, Ruth

2005-01-01

Mark Haddon's "The Curious Incident of the Dog in the Night-Time" was the crossover publishing sensation of 2003. It has been the subject of widespread critical and commercial acclaim and has won prestigious UK prizes including the Whitbread Book of the Year and the Guardian's Children's Fiction Prize. It is still enjoying considerable commercial…

Patterns of Developmental Change in Infants' Nighttime Sleep Awakenings from 6 through 36 Months of Age

ERIC Educational Resources Information Center

Weinraub, Marsha; Bender, Randall H.; Friedman, Sarah L.; Susman, Elizabeth J.; Knoke, Bonnie; Bradley, Robert; Houts, Renate; Williams, Jason

2012-01-01

Nighttime sleep awakenings and infant and family characteristics were measured longitudinally in more than 1,200 infants when the infants were 6, 15, 24, and 36 months old. By 6 months of age, the majority of children slept through the night, awakening their mothers only about once or twice per week. However, not all children followed this…

Monster in My Closet: An Exploratory Study of the Relationship between Parent-Child Co-Sleeping and Nighttime Fears of Preschool Children

ERIC Educational Resources Information Center

Chang, I. Joyce; Pettit, Rebecca W.; Kennedy, Gregory

2004-01-01

Children's nighttime fears, such as monsters in the closet, have been a common issue for the American. In children's cognitive development, vivid imagination has been recognized as a cause of fear, but not all children around the globe share this common experience. This qualitative, exploratory study examined the relationship between parent-child…

Nocturnal emergency department visits, duration of symptoms and risk of hospitalisation among adults with asthma exacerbations: a multicentre observational study.

PubMed

Yasuda, Hideto; Hagiwara, Yusuke; Watase, Hiroko; Hasegawa, Kohei

2016-08-12

We sought to compare the characteristics of patients with asthma presenting to the emergency department (ED) during the night-time with those of patients presenting at other times of the day, and to determine whether the time of ED presentation is associated with the risk of hospitalisation. A multicentre chart review study of 23 EDs across Japan. Patients aged 18-54 years with a history of physician-diagnosed asthma, presented to the ED between January 2009 and December 2011 OUTCOME MEASURES: The outcome of interest was hospitalisation, including admissions to an observation unit, inpatient unit and intensive care unit. Among the 1354 patients (30.1% in the night-time group vs 69.9% in the other time group) included in this study, the median age was 34 years and ∼40% were male. Overall 145 patients (10.7%) were hospitalised. Patients in the night-time group were more likely to have a shorter duration of symptoms (≤3 hours) before ED presentation than those in the other time group (25.9% in night-time vs 13.4% in other times; p<0.001). In contrast, there were no significant differences in respiratory rate, initial peak expiratory flow or ED asthma treatment between the two groups (p>0.05). Similarly, the risk of hospitalisation did not differ between the two groups (11.3% in night-time vs 10.5% in other times; p=0.65). In a multivariable model adjusting for potential confounders, the risk of hospitalisation in the night-time group was not statistically different from the other time group (OR, 1.10; 95% CI 0.74 to 1.61; p=0.63). This multicentre study in Japan demonstrated no significant difference in the risk of hospitalisations according to the time of ED presentation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

CALIPSO lidar calibration at 532 nm: version 4 nighttime algorithm

NASA Astrophysics Data System (ADS)

Kar, Jayanta; Vaughan, Mark A.; Lee, Kam-Pui; Tackett, Jason L.; Avery, Melody A.; Garnier, Anne; Getzewich, Brian J.; Hunt, William H.; Josset, Damien; Liu, Zhaoyan; Lucker, Patricia L.; Magill, Brian; Omar, Ali H.; Pelon, Jacques; Rogers, Raymond R.; Toth, Travis D.; Trepte, Charles R.; Vernier, Jean-Paul; Winker, David M.; Young, Stuart A.

2018-03-01

Data products from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on board Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) were recently updated following the implementation of new (version 4) calibration algorithms for all of the Level 1 attenuated backscatter measurements. In this work we present the motivation for and the implementation of the version 4 nighttime 532 nm parallel channel calibration. The nighttime 532 nm calibration is the most fundamental calibration of CALIOP data, since all of CALIOP's other radiometric calibration procedures - i.e., the 532 nm daytime calibration and the 1064 nm calibrations during both nighttime and daytime - depend either directly or indirectly on the 532 nm nighttime calibration. The accuracy of the 532 nm nighttime calibration has been significantly improved by raising the molecular normalization altitude from 30-34 km to the upper possible signal acquisition range of 36-39 km to substantially reduce stratospheric aerosol contamination. Due to the greatly reduced molecular number density and consequently reduced signal-to-noise ratio (SNR) at these higher altitudes, the signal is now averaged over a larger number of samples using data from multiple adjacent granules. Additionally, an enhanced strategy for filtering the radiation-induced noise from high-energy particles was adopted. Further, the meteorological model used in the earlier versions has been replaced by the improved Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2), model. An aerosol scattering ratio of 1.01 ± 0.01 is now explicitly used for the calibration altitude. These modifications lead to globally revised calibration coefficients which are, on average, 2-3 % lower than in previous data releases. Further, the new calibration procedure is shown to eliminate biases at high altitudes that were present in earlier versions and consequently leads to an improved representation of stratospheric aerosols. Validation results using airborne lidar measurements are also presented. Biases relative to collocated measurements acquired by the Langley Research Center (LaRC) airborne High Spectral Resolution Lidar (HSRL) are reduced from 3.6 % ± 2.2 % in the version 3 data set to 1.6 % ± 2.4 % in the version 4 release.

Availability and night-time use of electronic entertainment and communication devices are associated with short sleep duration and obesity among Canadian children.

PubMed

Chahal, H; Fung, C; Kuhle, S; Veugelers, P J

2013-02-01

What is already known about this subject Short sleep duration is a risk factor for obesity. Television (TV) in the bedroom has been shown to be associated with excess body weight in children. Children increasingly use other electronic entertainment and communication devices (EECDs) such as video games, computers, and smart phones. What this study adds Access to and night-time use of EECDs are associated with shortened sleep duration, excess body weight, poorer diet quality, and lower physical activity levels. Our findings reinforce existing recommendations pertaining to TV and Internet access by the American Academy of Pediatrics and suggest to have these expanded to restricted availability of video games and smart phones in children's bedrooms. While the prevalence of childhood obesity and access to and use of electronic entertainment and communication devices (EECDs) have increased in the past decades, no earlier study has examined their interrelationship. To examine whether night-time access to and use of EECDs are associated with sleep duration, body weights, diet quality, and physical activity of Canadian children. A representative sample of 3398 grade 5 children in Alberta, Canada, was surveyed. The survey included questions on children's lifestyles and health behaviours, the Harvard Youth/Adolescent Food Frequency questionnaire, a validated questionnaire on physical activity, and measurements of heights and weights. Random effect models were used to assess the associations of night-time access to and use of EECDs with sleep, diet quality, physical activity, and body weights. Sixty-four percent of parents reported that their child had access to one or more EECDs in their bedroom. Access to and night-time use of EECDs were associated with shortened sleep duration, excess body weight, poorer diet quality, and lower physical activity levels in a statistically significant manner. Limiting the availability of EECDs in children's bedrooms and discouraging their night-time use may be considered as a strategy to promote sleep and reduce childhood obesity. © 2012 The Authors. Pediatric Obesity © 2012 International Association for the Study of Obesity.

Increasing sensitivity of methane emission measurements in rice through deployment of ‘closed chambers’ at nighttime

PubMed Central

Wassmann, Reiner; Alberto, Ma. Carmelita; Tirol-Padre, Agnes; Hoang, Nghia Trong; Romasanta, Ryan; Centeno, Caesar Arloo; Sander, Bjoern Ole

2018-01-01

This study comprises field experiments on methane emissions from rice fields conducted with an Eddy-Covariance (EC) system as well as test runs for a modified closed chamber approach based on measurements at nighttime. The EC data set covers 4 cropping seasons with highly resolved emission rates (raw data in 10 Hz frequency have been aggregated to 30-min records). The diel patterns were very pronounced in the two dry seasons with peak emissions at early afternoon and low emissions at nighttime. These diel patterns were observed at all growing stages of the dry seasons. In the two wet seasons, the diel patterns were only visible during the vegetative stages while emission rates during reproductive and ripening stages remained within a fairly steady range and did not show any diel patterns. In totality, however, the data set revealed a very strong linear relationship between nocturnal emissions (12-h periods) and the full 24-h periods resulting in an R2-value of 0.8419 for all data points. In the second experiment, we conducted test runs for chamber measurements at nighttime with much longer deployment times (6 h) as compared to measurements at daylight (typically for 30 min). Conducting chamber measurements at nighttime excluded drastic changes of temperatures and CO2 concentrations. The data also shows that increases in CH4 concentrations remained on linear trajectory over a 6h period at night. While end CH4 concentrations were consistently >3.5 ppm, this long-term enclosure represents a very robust approach to quantify emissions as compared to assessing short-term concentration increases over time near the analytical detection limit. Finally, we have discussed the potential applications of this new approach that would allow emission measurements even when conventional (daytime) measurements will not be suitable. Nighttime chamber measurements offer an alternative to conventional (daytime) measurements if either (i) baseline emissions are at a very low level, (ii) differences of tested crop treatments or varieties are very small or (iii) the objective is to screen a large number of rice varieties for taking advantage of progress in genome sequencing. PMID:29390000

Atmospheric aerosol composition and source apportionments to aerosol in southern Taiwan

NASA Astrophysics Data System (ADS)

Tsai, Ying I.; Chen, Chien-Lung

In this study, the chemical characteristics of winter aerosol at four sites in southern Taiwan were determined and the Gaussian Trajectory transfer coefficient model (GTx) was then used to identify the major air pollutant sources affecting the study sites. Aerosols were found to be acidic at all four sites. The most important constituents of the particulate matter (PM) by mass were SO 42-, organic carbon (OC), NO 3-, elemental carbon (EC) and NH 4+, with SO 42-, NO 3-, and NH 4+ together constituting 86.0-87.9% of the total PM 2.5 soluble inorganic salts and 68.9-78.3% of the total PM 2.5-10 soluble inorganic salts, showing that secondary photochemical solution components such as these were the major contributors to the aerosol water-soluble ions. The coastal site, Linyuan (LY), had the highest PM mass percentage of sea salts, higher in the coarse fraction, and higher sea salts during daytime than during nighttime, indicating that the prevailing daytime sea breeze brought with it more sea-salt aerosol. Other than sea salts, crustal matter, and EC in PM 2.5 at Jenwu (JW) and in PM 2.5-10 at LY, all aerosol components were higher during nighttime, due to relatively low nighttime mixing heights limiting vertical and horizontal dispersion. At JW, a site with heavy traffic loadings, the OC/EC ratio in the nighttime fine and coarse fractions of approximately 2.2 was higher than during daytime, indicating that in addition to primary organic aerosol (POA), secondary organic aerosol (SOA) also contributed to the nighttime PM 2.5. This was also true of the nighttime coarse fraction at LY. The GTx produced correlation coefficients ( r) for simulated and observed daily concentrations of PM 10 at the four sites (receptors) in the range 0.45-0.59 and biases from -6% to -20%. Source apportionment indicated that point sources were the largest PM 10 source at JW, LY and Daliao (DL), while at Meinung (MN), a suburban site with less local PM 10, SO x and NO x emissions, upwind boundary concentration was the major PM 10 source, followed by point sources and top boundary concentration.

Variation in diurnal sedation in mechanically ventilated patients who are managed with a sedation protocol alone or a sedation protocol and daily interruption.

PubMed

Mehta, Sangeeta; Meade, Maureen; Burry, Lisa; Mallick, Ranjeeta; Katsios, Christina; Fergusson, Dean; Dodek, Peter; Burns, Karen; Herridge, Margaret; Devlin, John W; Tanios, Maged; Fowler, Robert; Jacka, Michael; Skrobik, Yoanna; Olafson, Kendiss; Cook, Deborah

2016-08-01

Mechanically ventilated patients may receive more sedation during the night than during the day, potentially delaying extubation. We compared nighttime and daytime benzodiazepine and opioid administration in adult patients enrolled in a multicenter sedation trial comparing protocolized sedation alone or protocolized sedation combined with daily sedation interruption; and we evaluated whether nighttime and daytime doses were associated with liberation from mechanical ventilation. This is a secondary analysis of a randomized trial which was conducted in 16 North American medical-surgical ICUs. In all 423 patients, nurses applied a validated sedation scale hourly to titrate benzodiazepine and opioid infusions to achieve a light level of sedation. Using fentanyl equivalents and midazolam equivalents, we compared dosages administered during night (19:00 to 07:00) and day (07:00 to 19:00) shifts. Using multivariable logistic regression we evaluated the association between nighttime and daytime opioid and sedative doses, and spontaneous breathing trial (SBT) conduct, SBT success, and extubation. Nighttime benzodiazepine and opioid doses were significantly higher than daytime doses (mean difference midazolam equivalents 23.3 mg, 95 % CI 12.9, 33.8, p < 0.0001; mean difference fentanyl equivalents 356 mcg, 95 % CI 130, 582, p = 0.0021). Mean Sedation Agitation Scale score was similar between night and day, and was at target (3.2 vs 3.3, 95 % CI -0.05, 0.02, p = 0.35). Self-reported nurse workload was similar during the night and day. Patients were more often restrained during day shifts (76.3 % vs 73.7 %, p < 0.0001), and there were more unintentional device removals during the day compared with night (15.9 % vs 9.1 %, p < 0.0001). Increases in nighttime drug doses were independently associated with failure to meet SBT screening criteria, SBT failure, and the decision not to extubate the patient despite successful SBT. Patients received higher doses of opioids and benzodiazepines at night. Higher nighttime doses were associated with SBT failure and delayed extubation. ClinicalTrials.gov NCT00675363 . Registered 7 May 2008.

An optical to IR sky brightness model for the LSST

NASA Astrophysics Data System (ADS)

Yoachim, Peter; Coughlin, Michael; Angeli, George Z.; Claver, Charles F.; Connolly, Andrew J.; Cook, Kem; Daniel, Scott; Ivezić, Željko; Jones, R. Lynne; Petry, Catherine; Reuter, Michael; Stubbs, Christopher; Xin, Bo

2016-07-01

To optimize the observing strategy of a large survey such as the LSST, one needs an accurate model of the night sky emission spectrum across a range of atmospheric conditions and from the near-UV to the near-IR. We have used the ESO SkyCalc Sky Model Calculator1, 2 to construct a library of template spectra for the Chilean night sky. The ESO model includes emission from the upper and lower atmosphere, scattered starlight, scattered moonlight, and zodiacal light. We have then extended the ESO templates with an empirical fit to the twilight sky emission as measured by a Canon all-sky camera installed at the LSST site. With the ESO templates and our twilight model we can quickly interpolate to any arbitrary sky position and date and return the full sky spectrum or surface brightness magnitudes in the LSST filter system. Comparing our model to all-sky observations, we find typical residual RMS values of +/-0.2-0.3 magnitudes per square arcsecond.

Touch the Cosmos: The 2012 International Earth and Sky Photo Contest

NASA Astrophysics Data System (ADS)

Walker, C. E.; Tafreshi, B.; Simmons, M.

2013-04-01

In April 2012, the National Optical Astronomy Observatory in partnership with The World At Night organized the Third International Earth and Sky Photo Contest on the importance of preserving dark skies for the Dark Skies Awareness theme of Global Astronomy Month. At the Fall 2012 ASP conference, a presentation on the Earth and Sky Photo Contest was made. The intended outcomes of the 10-minute oral talk were 1) to inspire visual learners to be more aware of the disappearing starry night sky due to light pollution, 2) to provide some basic understanding of what the issues are surrounding light pollution, 3) to provide incentive to get people to participate in the photo contest as a way of promoting dark skies awareness and 4) to provide a stepping stone to more active involvement in dark skies preservation. With more than half of the world's population in cities, Earth and Sky photos of dark, starry skies offer the next best thing to being there.

Spatial Model of Sky Brightness Magnitude in Langkawi Island, Malaysia

NASA Astrophysics Data System (ADS)

Redzuan Tahar, Mohammad; Kamarudin, Farahana; Umar, Roslan; Khairul Amri Kamarudin, Mohd; Sabri, Nor Hazmin; Ahmad, Karzaman; Rahim, Sobri Abdul; Sharul Aikal Baharim, Mohd

2017-03-01

Sky brightness is an essential topic in the field of astronomy, especially for optical astronomical observations that need very clear and dark sky conditions. This study presents the spatial model of sky brightness magnitude in Langkawi Island, Malaysia. Two types of Sky Quality Meter (SQM) manufactured by Unihedron are used to measure the sky brightness on a moonless night (or when the Moon is below the horizon), when the sky is cloudless and the locations are at least 100 m from the nearest light source. The selected locations are marked by their GPS coordinates. The sky brightness data obtained in this study were interpolated and analyzed using a Geographic Information System (GIS), thus producing a spatial model of sky brightness that clearly shows the dark and bright sky areas in Langkawi Island. Surprisingly, our results show the existence of a few dark sites nearby areas of high human activity. The sky brightness of 21.45 mag arcsec{}-2 in the Johnson-Cousins V-band, as the average of sky brightness equivalent to 2.8 × {10}-4{cd} {{{m}}}-2 over the entire island, is an indication that the island is, overall, still relatively dark. However, the amount of development taking place might reduce the number in the near future as the island is famous as a holiday destination.

Prevalence and correlates of drink driving within patrons of Australian night-time entertainment precincts.

PubMed

Curtis, Ashlee; Coomber, Kerri; Hyder, Shannon; Droste, Nic; Pennay, Amy; Jenkinson, Rebecca; Mayshak, Richelle; Miller, Peter G

2016-10-01

Drink driving is a significant public health concern, and contributes to many road fatalities worldwide. The current study is the first to examine the prevalence and correlates of drink driving behavior in a sample of night-time entertainment precinct attendees in Australia. Interviews were conducted with 4214 night-time entertainment precinct attendees in two metropolitan and three regional cities in Australia. Seven correlates of self-reported drink driving were examined: gender, age, occupation, blood alcohol concentration (BAC), alcohol consumed prior to attending a licensed venue, energy drink consumption, and other drug consumption. Fourteen percent of night-time entertainment precinct attendees reported drink driving in the past three months. Bivariate logistic regression models indicated that males were significantly more likely than females to report drink driving in the past three months. Blue-collar workers and sales/clerical/administrative workers were significantly more likely to report drink driving behavior in the past three months than white-collar workers. The likelihood of reporting drink driving during the three months prior to interview significantly increased as BAC on the current night out increased, and when patrons reported engaging in pre-drinking or other drug use. The multivariate model presented a similar pattern of results, however BAC and pre-drinking on the night of the interview were no longer independent significant predictors. Males, blue collar/sales/clerical/administrative workers, and illicit drug consumers were more likely to report engaging in drink driving behavior than their counterparts. Interventions should focus on addressing the considerable proportion night-time entertainment precinct attendees who report engaging in drink driving behavior. Copyright © 2016 Elsevier Ltd. All rights reserved.

Measuring nighttime spawning behavior of chum salmon using a dual-frequency identification sonar (DIDSON)

USGS Publications Warehouse

Tiffan, K.F.; Rondorf, D.W.

2005-01-01

The striking body coloration and morphology that Pacific salmon display during spawning coupled with elaborate courtship behaviors suggest that visual cues are important during their reproductive period. To date, virtually all existing information on chum salmon (Oncorhynchus keta) spawning behavior has been derived from studies conducted during the daytime, and has contributed to the assumption that salmon do not spawn at night. We tested this assumption using a new technology - a dual-frequency identification sonar (DIDSON) - to describe and measure nighttime spawning behavior of wild chum salmon in the Columbia River. The DIDSON produces detailed, video-like images using sound, which enabled us to collect behavioral information at night in complete darkness. The display of DIDSON images enabled fish movements and behaviors to be spatially quantified. We collected continuous observational data on 14 pairs of chum salmon in a natural spawning channel during the daytime and nighttime. Spawners of both genders were observed chasing intruders during nighttime and daytime as nests were constructed. Regardless of diel period, females were engaged in digging to both construct nests and cover eggs, and courting males exhibited the pre-spawning behavior of tail crossing. We observed a total of 13 spawning events, of which nine occurred at night and four occurred during the day. The behaviors we observed at night suggest the assumption that chum salmon do not spawn at night is false. Once chum salmon begin nest construction, visual cues are apparently not required for courtship, nest defense, and spawning. We speculate that non-visual cues (e.g. tactile and auditory) enable chum salmon to carry out most spawning behaviors at night. Our findings have implications for how nighttime flows from hydroelectric dams on the Columbia River are managed for power production and protection of imperiled salmon stocks.

Arterial stiffness in obstructive sleep apnoea: Is there a difference between daytime and night-time?

PubMed

Sarinc Ulasli, Sevinc; Sariaydin, Muzaffer; Ozkececi, Gulay; Gunay, Ersin; Halici, Bilal; Unlu, Mehmet

2016-11-01

Obstructive sleep apnoea syndrome (OSAS) is a common chronic systemic disease in the general population, with known associated cardiovascular outcomes. We aimed to investigate arterial stiffness in OSAS patients and compare daytime and night-time values with control subjects. A total of 104 patients undergoing investigation for OSAS with polysomnography also underwent pulse wave velocity (PWV) and augmentation index (AIx) measurements with Mobil-O-Graph for 24 h. Eighty-two patients were found to have OSAS and 22 did not have OSAS and acted as controls. PWV values of the 82 OSAS patients during the 24-h period, both daytime and night-time, were significantly higher than that of the control subjects. Moreover, night-time levels of AIx were significantly higher in OSAS patients than control subjects (P = 0.025). PWV during night-time was higher than daytime measurements in OSAS patients (P = 0.012). Apnoea hypopnoea index (AHI) was significantly correlated with PWV and AIx over 24 h (P = 0.0001, r = 0.412; P = 0.002, r = 0.333, respectively). Positive correlations were also found between oxygen desaturation index (ODI) with PWV and AIx during the night (P = 0.0001, r = 0.480; P = 0.002, r = 0.325, respectively). However, daytime AIx was not significantly correlated with ODI (P = 0.052, r = 0.205). OSAS patients, without known cardiovascular disease, have increased PWV, indicating an increased arterial stiffness, compared with control subjects and correlations between AHI and arterial stiffness indices suggest increased arterial stiffness with increased disease severity. Therefore, arterial stiffness should be considered as a possible cause for cardiovascular complications in OSAS patients. © 2016 Asian Pacific Society of Respirology.

Observations of the Morning Development of the Urban Boundary Layer Over London, UK, Taken During the ACTUAL Project

NASA Astrophysics Data System (ADS)

Halios, Christos H.; Barlow, Janet F.

2018-03-01

The study of the boundary layer can be most difficult when it is in transition and forced by a complex surface, such as an urban area. Here, a novel combination of ground-based remote sensing and in situ instrumentation in central London, UK, is deployed, aiming to capture the full evolution of the urban boundary layer (UBL) from night-time until the fully-developed convective phase. In contrast with the night-time stable boundary layer observed over rural areas, the night-time UBL is weakly convective. Therefore, a new approach for the detection of the morning-transition and rapid-growth phases is introduced, based on the sharp, quasi-linear increase of the mixing height. The urban morning-transition phase varied in duration between 0.5 and 4 h and the growth rate of the mixing layer during the rapid-growth phase had a strong positive relationship with the convective velocity scale, and a weaker, negative relationship with wind speed. Wind shear was found to be higher during the night-time and morning-transition phases than the rapid-growth phase and the shear production of turbulent kinetic energy near the mixing-layer top was around six times larger than surface shear production in summer, and around 1.5 times larger in winter. In summer under low winds, low-level jets dominated the UBL, and shear production was greater than buoyant production during the night-time and the morning-transition phase near the mixing-layer top. Within the rapid-growth phase, buoyant production dominated at the surface, but shear production dominated in the upper half of the UBL. These results imply that regional flows such as low-level jets play an important role alongside surface forcing in determining UBL structure and growth.

Effects of day-time exposure to different light intensities on light-induced melatonin suppression at night.

PubMed

Kozaki, Tomoaki; Kubokawa, Ayaka; Taketomi, Ryunosuke; Hatae, Keisuke

2015-07-04

Bright nocturnal light has been known to suppress melatonin secretion. However, bright light exposure during the day-time might reduce light-induced melatonin suppression (LIMS) at night. The effective proportion of day-time light to night-time light is unclear; however, only a few studies on accurately controlling both day- and night-time conditions have been conducted. This study aims to evaluate the effect of different day-time light intensities on LIMS. Twelve male subjects between the ages of 19 and 23 years (mean ± S.D., 20.8 ± 1.1) gave informed consent to participate in this study. They were exposed to various light conditions (<10, 100, 300, 900 and 2700 lx) between the hours of 09:00 and 12:00 (day-time light conditions). They were then exposed to bright light (300 lx) again between 01:00 and 02:30 (night-time light exposure). They provided saliva samples before (00:55) and after night-time light exposure (02:30). A one-tailed paired t test yielded significant decrements of melatonin concentration after night-time light exposure under day-time dim, 100- and 300-lx light conditions. No significant differences exist in melatonin concentration between pre- and post-night-time light exposure under day-time 900- and 2700-lx light conditions. Present findings suggest the amount of light exposure needed to prevent LIMS caused by ordinary nocturnal light in individuals who have a general life rhythm (sleep/wake schedule). These findings may be useful in implementing artificial light environments for humans in, for example, hospitals and underground shopping malls.

A global analysis of the urban heat island effect based on multisensor satellite data

NASA Astrophysics Data System (ADS)

Xiao, J.; Frolking, S. E.; Milliman, T. E.; Schneider, A.; Friedl, M. A.

2017-12-01

Human population is rapidly urbanizing. In much of the world, cities are prone to hotter weather than surrounding rural areas - so-called `urban heat islands' - and this effect can have mortal consequences during heat waves. During the daytime, when the surface energy balance is driven by incoming solar radiation, the magnitude of urban warming is strongly influenced by surface albedo and the capacity to evaporate water (i.e., there is a strong relationship between vegetated land fraction and the ratio of sensible to latent heat loss or Bowen ratio). At nighttime, urban cooling is often inhibited by the thermal inertia of the built environment and anthropogenic heat exhaust from building and transportation energy use. We evaluated a suite of global remote sensing data sets representing a range of urban characteristics against MODIS-derived land-surface temperature differences between urban and surrounding rural areas. We included two new urban datasets in this analysis - MODIS-derived change in global urban extent and global urban microwave backscatter - along with several MODIS standard products and DMSP/OLS nighttime lights time series data. The global analysis spanned a range of urban characteristics that likely influence the magnitude of daytime and/or nighttime urban heat islands - urban size, population density, building density, state of development, impervious fraction, eco-climatic setting. Specifically, we developed new satellite datasets and synthesizing these with existing satellite data into a global database of urban land surface parameters, used two MODIS land surface temperature products to generate time series of daytime and nighttime urban heat island effects for 30 large cities across the globe, and empirically analyzed these data to determine specifically which remote sensing-based characterizations of global urban areas have explanatory power with regard to both daytime and nighttime urban heat islands.

Clinical characteristics and psychosocial impact of different reflux time in gastroesophageal reflux disease patients.

PubMed

Chen, Jiann-Hwa; Wen, Shu-Hui; Hsu, Ching-Sheng; Yi, Chih-Hsun; Liu, Tso-Tsai; Chen, Chien-Lin; Wang, Chia-Chi

2017-02-01

Gastroesophageal reflux disease (GERD) is an emerging disease, and can impair quality of life and sleep. This study aimed to investigate whether GERD patients with different timings of reflux symptoms have different clinical characteristics. This study prospectively enrolled individuals who underwent upper gastrointestinal endoscopy during a health checkup. Each participant completed all questionnaires including Reflux Disease Questionnaire, Nighttime GERD questionnaire, Pittsburg Sleep Quality Index, Taiwanese Depression Questionnaire, and State-Trait Anxiety Inventory. Combined reflux was defined as the timing of reflux symptoms occurring at both daytime and nighttime. A total of 2604 participants were enrolled. Of them, 651 symptomatic GERD patients, according to the Reflux Disease Questionnaire score, were recruited for final analysis. Of them, 224 (34.4%) had erosive esophagitis on endoscopy. According to the timing of reflux symptoms, 184 (28.3%) were assigned to the daytime reflux group, 71 (10.9%) to the nighttime reflux group, and 396 (60.8%) to the combined reflux group. In post hoc analysis, the combined reflux group had a significantly higher Reflux Disease Questionnaire score than the daytime reflux group (p < 0.0001). Combined and nighttime reflux groups had higher body mass index and longer duration (> 12 years) of education than the daytime reflux group (p < 0.05). There was no difference in Pittsburg Sleep Quality Index, Taiwanese Depression Questionnaire, and State-Trait Anxiety Inventory scores among three groups. GERD patients with combined daytime and nighttime reflux of have more troublesome symptoms than those with daytime reflux. GERD patients with different timings of reflux symptoms have different clinical characteristics in terms of body mass index and duration of education, but not in terms of esophageal inflammation, quality of sleep, and psychosocial status. Copyright © 2016. Published by Elsevier B.V.

Graduated driver license nighttime compliance in U.S. teen drivers involved in fatal motor vehicle crashes.

PubMed

Carpenter, Dustin; Pressley, Joyce C

2013-07-01

Examination of teen driver compliance with graduated driver licensing (GDL) laws could be instrumental in identifying factors associated with persistently high motor vehicle mortality rates. Fatality analysis reporting system (FARS) data from the years 2006 to 2009 were used in this nation-wide cross-sectional study of drivers covered by a state nighttime GDL law (n=3492). A new definition of weekend, based on the school night in relation to the teenage social landscape, redefined Friday night as a weekend night and Sunday night as a weekday/school night and compared it to previous weekend definitions. Multiple logistic regression was used to examine independent effects of demographic, behavioral, environmental, contextual, and other factors on compliance with nighttime GDL laws. All analyses were performed in Stata version 11. Given coverage under nighttime GDL laws, drivers aged 15-17 years were non-compliant in 14.9% of the fatal MVCs in which they were involved, and nearly one-fifth (18.8%) of all fatalities aged 15-17 years were associated with non-compliance. Mortality risk was 10% higher using a revised social (school night) versus traditional (Sat-Sun) weekend definitions. In multivariable analysis, drivers non-compliant with nighttime GDL laws were more likely to be drinking (OR=4.97, 3.85-6.40), unbelted (OR=1.58, 1.25-1.99), driving on the weekend (OR=1.82, 1.47-2.24), and killed (OR=1.31, 1.04-1.65). GDL non-compliance contributes to teen motor vehicle mortality. Legislative and enforcement efforts targeting non-school night driving, seatbelt nonuse and alcohol have potential to further reduce teen driving mortality. Copyright © 2012 Elsevier Ltd. All rights reserved.

Tamsulosin reduces nighttime urine production in benign prostatic hyperplasia patients with nocturnal polyuria: a prospective open-label long-term study using frequency-volume chart.

PubMed

Kojima, Yoshiyuki; Sasaki, Shoichi; Imura, Makoto; Kubota, Yasue; Hayashi, Yutaro; Kohri, Kenjiro

2012-01-01

The effects of tamsulosin treatment on changes in frequency-volume chart (FVC) data, especially nighttime urine production, over time were assessed, and the mechanisms underlying the improvement of nocturia in benign prostatic hyperplasia (BPH) patients with nocturnal polyuria (NP) are discussed. A total of 104 patients with lower urinary tract symptoms secondary to BPH were enrolled. After enrollment in the study, the patients were treated with tamsulosin (0.2 mg) once daily. Visits were scheduled every 4 weeks until week 12 (month 3) after study entry, and then every 12 weeks subsequently. All patients completed the International Prostate Symptom Score (IPSS), quality of life (QOL) index, and 3-day FVC, and underwent uroflowmetry at enrollment and on each visit. Eighty-two patients (mean age: 70.9 ± 7.1 years) were analyzed for 24 months after treatment. Patients were divided into two groups, NP and nonNP, based on FVC outcome. The IPSS, QOL index, and maximum flow rate improved during the 24-month period after treatment in both groups. Mean daytime urine volume significantly increased in the NP group, but no changes were detected in the nonNP group. Mean nighttime urine frequency significantly decreased in the NP group over a 24-month period, and was associated with a significant decrease in nighttime urine volume that was not found in the nonNP group. Maximum voided volume increased most months after treatment in both groups. The present long-term prospective study using FVC demonstrated that tamsulosin reduced nighttime urine production in BPH patients with NP. Copyright © 2011 Wiley Periodicals, Inc.

Evaluation of Precipitation Simulated by Seven SCMs against the ARM Observations at the SGP Site

NASA Technical Reports Server (NTRS)

Song, Hua; Lin, Wuyin; Lin, Yanluan; Wolf, Audrey B.; Neggers, Roel; Donner, Leo J.; Del Genio, Anthony D.; Liu, Yangang

2013-01-01

This study evaluates the performances of seven single-column models (SCMs) by comparing simulated surface precipitation with observations at the Atmospheric Radiation Measurement Program Southern Great Plains (SGP) site from January 1999 to December 2001. Results show that although most SCMs can reproduce the observed precipitation reasonably well, there are significant and interesting differences in their details. In the cold season, the model-observation differences in the frequency and mean intensity of rain events tend to compensate each other for most SCMs. In the warm season, most SCMs produce more rain events in daytime than in nighttime, whereas the observations have more rain events in nighttime. The mean intensities of rain events in these SCMs are much stronger in daytime, but weaker in nighttime, than the observations. The higher frequency of rain events during warm-season daytime in most SCMs is related to the fact that most SCMs produce a spurious precipitation peak around the regime of weak vertical motions but rich in moisture content. The models also show distinct biases between nighttime and daytime in simulating significant rain events. In nighttime, all the SCMs have a lower frequency of moderate-to-strong rain events than the observations for both seasons. In daytime, most SCMs have a higher frequency of moderate-to-strong rain events than the observations, especially in the warm season. Further analysis reveals distinct meteorological backgrounds for large underestimation and overestimation events. The former occur in the strong ascending regimes with negative low-level horizontal heat and moisture advection, whereas the latter occur in the weak or moderate ascending regimes with positive low-level horizontal heat and moisture advection.

Automated external defibrillators inaccessible to more than half of nearby cardiac arrests in public locations during evening, nighttime, and weekends.

PubMed

Hansen, Carolina Malta; Wissenberg, Mads; Weeke, Peter; Ruwald, Martin Huth; Lamberts, Morten; Lippert, Freddy Knudsen; Gislason, Gunnar Hilmar; Nielsen, Søren Loumann; Køber, Lars; Torp-Pedersen, Christian; Folke, Fredrik

2013-11-12

Despite wide dissemination, use of automated external defibrillators (AEDs) in community settings is limited. We assessed how AED accessibility affected coverage of cardiac arrests in public locations. We identified cardiac arrests in public locations (1994-2011) in terms of location and time and viewed them in relation to the location and accessibility of all AEDs linked to the emergency dispatch center as of December 31, 2011, in Copenhagen, Denmark. AED coverage of cardiac arrests was defined as cardiac arrests within 100 m (109.4 yd) of an AED and further categorized according to AED accessibility at the time of cardiac arrest. Daytime, evening, and nighttime were defined as 8 am to 3:59 pm, 4 to 11:59 pm, and midnight to 7:59 am, respectively. Of 1864 cardiac arrests in public locations, 61.8% (n=1152) occurred during the evening, nighttime, or weekends. Of 552 registered AEDs, 9.1% (n=50) were accessible at all hours, and 96.4% (n=532) were accessible during the daytime on all weekdays. Regardless of AED accessibility, 28.8% (537 of 1864) of all cardiac arrests were covered by an AED. Limited AED accessibility decreased coverage of cardiac arrests by 4.1% (9 of 217) during the daytime on weekdays and by 53.4% (171 of 320) during the evening, nighttime, and weekends. Limited AED accessibility at the time of cardiac arrest decreased AED coverage by 53.4% during the evening, nighttime, and weekends, which is when 61.8% of all cardiac arrests in public locations occurred. Thus, not only strategic placement but also uninterrupted AED accessibility warrant attention if public-access defibrillation is to improve survival after out-of-hospital cardiac arrest.

The influence of nighttime feeding of carbohydrate or protein combined with exercise training on appetite and cardiometabolic risk in young obese women.

PubMed

Ormsbee, Michael J; Kinsey, Amber W; Eddy, Wyatt R; Madzima, Takudzwa A; Arciero, Paul J; Figueroa, Arturo; Panton, Lynn B

2015-01-01

Single macronutrient intake prior to sleep reduces appetite but may negatively impact insulin sensitivity in sedentary obese women. The present study examined the additive impact of nighttime feeding of whey (WH), casein (CAS), or carbohydrate (CHO) combined with exercise training on appetite, cardiometabolic health, and strength in obese women. Thirty-seven sedentary obese women (WH, n = 13, body mass index (BMI) 34.4 ± 1.3 kg/m(2); CAS, n = 14, BMI 36.5 ± 1.8 kg/m(2); CHO, n = 10, BMI 33.1 ± 1.7 kg/m(2)) consumed WH, CAS, or CHO (140-150 kcal/serving), every night of the week, within 30 min of sleep, for 4 weeks. Supervised exercise training (2 days of resistance training and 1 day of high-intensity interval training) was completed 3 days per week. Pre- and post-testing measurements included appetite ratings, mood state, resting metabolic rate, fasting lipids, glucose, and hormonal responses (insulin, leptin, adiponectin, hs-CRP, IGF-1, and cortisol), body composition, and strength. Nighttime intake of CAS significantly (p < 0.05) increased morning satiety (pretraining, 25 ± 5; post-training 41 ± 6) more than WH (pretraining, 34 ± 5; post-training, 35 ± 6) or CHO (pre 40 ± 8, post 43 ± 7). Exercise training increased lean mass and strength, decreased body fat, and improved mood state in all groups. No other differences were noted. Nighttime feeding of CAS combined with exercise training increased morning satiety more than WH or CHO. Nighttime feeding for 4 weeks did not impact insulin sensitivity (assessed via homeostatic model assessment of insulin resistance) when combined with exercise training in obese women. ClinicalTrial.gov: NCT01830946.

Blood pressure response to CPAP treatment in subjects with obstructive sleep apnoea: the predictive value of 24-h ambulatory blood pressure monitoring.

PubMed

Castro-Grattoni, Anabel L; Torres, Gerard; Martínez-Alonso, Montserrat; Barbé, Ferran; Turino, Cecilia; Sánchez-de-la-Torre, Alicia; Cortijo, Anunciacion; Duran-Cantolla, Joaquin; Egea, Carlos; Cao, Gonzalo; Sánchez-de-la-Torre, Manuel

2017-10-01

The reduction in blood pressure (BP) with continuous positive airway pressure (CPAP) is modest and highly variable. In this study, we identified the variables that predict BP response to CPAP.24-h ambulatory BP monitoring (ABPM), C-reactive protein (CRP), leptin, adiponectin and 24-h urinary catecholamine were measured before and after 6 months of CPAP in obstructive sleep apnoea (OSA) patients.Overall, 88 middle-aged, obese male patients with severe OSA (median apnoea-hypopnoea index 42 events·h -1 ) were included; 28.4% had hypertension. 62 patients finished the study, and 60 were analysed. The daytime diastolic BP (-2 mmHg) and norepinephrine (-109.5 nmol·day -1 ) were reduced after CPAP, but no changes in the 24-h BP, night-time BP, dopamine, epinephrine, CRP, leptin or adiponectin were detected. The nocturnal normotension was associated with an increased night-time-BP (+4 mmHg) after CPAP, whereas nocturnal hypertension was associated with a reduction of 24-h BP (-3 mmHg). A multivariate linear regression model showed differential night-time BP changes after CPAP. Specifically, low night-time heart rate (<68 bpm) and BP dipper profile were associated with increased night-time BP and new diagnosis of nocturnal hypertension.Our results suggest that nocturnal hypertension, circadian BP pattern and night-time heart rate could be clinical predictors of BP response to CPAP and support the usefulness of 24-h ABPM for OSA patients before treatment initiation. These results need to be confirmed in further studies. Copyright ©ERS 2017.

Monitoring of body position and motion in children with severe cerebral palsy for 24 hours.

PubMed

Sato, Haruhiko; Iwasaki, Toshiyuki; Yokoyama, Misako; Inoue, Takenobu

2014-01-01

To investigate differences in position and body movements between children with severe cerebral palsy (CP) and children with typical development (TD) during the daytime and while asleep at night. Fifteen children with severe quadriplegic CP living at home (GMFCS level V, 7 males, 8 females; mean age 8 years 3 months; range 3-20 years) and 15 children with TD (6 males, 9 females; mean age 8 years 7 months; range 1-16 years) participated. Body position and movements were recorded for 24 h by a body position monitor and a physical activity monitor, respectively. The amount of time spent in one position and the durations of inactive periods during the daytime and during night-time sleep were computed and analyzed for group differences. In children with CP, the mean longest time spent in one position was longer than that in children with TD during night-time sleep (5.6 ± 3.5 h versus 1.6 ± 1.2 h). In contrast, no significant differences were found between the groups during the daytime (1.9 ± 1.1 h versus 1.6 ± 0.7 h). The mean longest time the body remained inactive was longer in the children with CP during both daytime and nighttime sleep (0.6 ± 0.3 h versus 0.3 ± 0.3 h for daytime, 1.4 ± 0.8 h versus 0.7 ± 0.3 h for nighttime). Children with severe CP living at home showed prolonged immobilized posture during night-time sleep when their caregivers would be likely to also be asleep. This may suggest that these children should receive postural care assistance at night.

Assessment of the NPOESS/VIIRS Nighttime Infrared Cloud Optical Properties Algorithms

NASA Astrophysics Data System (ADS)

Wong, E.; Ou, S. C.

2008-12-01

In this paper we will describe two NPOESS VIIRS IR algorithms used to retrieve microphysical properties for water and ice clouds during nighttime conditions. Both algorithms employ four VIIRS IR channels: M12 (3.7 μm), M14 (8.55 μm), M15 (10.7 μm) and M16 (12 μm). The physical basis for the two algorithms is similar in that while the Cloud Top Temperature (CTT) is derived from M14 and M16 for ice clouds the Cloud Optical Thickness (COT) and Cloud Effective Particle Size (CEPS) are derived from M12 and M15. The two algorithms depart in the different radiative transfer parameterization equations used for ice and water clouds. Both the VIIRS nighttime IR algorithms and the CERES split-window method employ the 3.7 μm and 10.7 μm bands for cloud optical properties retrievals, apparently based on similar physical principles but with different implementations. It is reasonable to expect that the VIIRS and CERES IR algorithms produce comparable performance and similar limitations. To demonstrate the VIIRS nighttime IR algorithm performance, we will select a number of test cases using NASA MODIS L1b radiance products as proxy input data for VIIRS. The VIIRS retrieved COT and CEPS will then be compared to cloud products available from the MODIS, NASA CALIPSO, CloudSat and CERES sensors. For the MODIS product, the nighttime cloud emissivity will serve as an indirect comparison to VIIRS COT. For the CALIPSO and CloudSat products, the layered COT will be used for direct comparison. Finally, the CERES products will provide direct comparison with COT as well as CEPS. This study can only provide a qualitative assessment of the VIIRS IR algorithms due to the large uncertainties in these cloud products.

Do convection-permitting models improve the representation of the impact of LUC?

NASA Astrophysics Data System (ADS)

Vanden Broucke, Sam; Van Lipzig, Nicole

2017-10-01

In this study we assess the added value of convection permitting scale (CPS) simulations in studies using regional climate models to quantify the bio-geophysical climate impact of land-use change (LUC). To accomplish this, a comprehensive model evaluation methodology is applied to both non-CPS and CPS simulations. The main characteristics of the evaluation methodology are (1) the use of paired eddy-covariance site observations (forest vs open land) and (2) a simultaneous evaluation of all surface energy budget components. Results show that although generally satisfactory, non-CPS simulations fall short of completely reproducing the observed LUC signal because of three key biases. CPS scale simulations succeed at significantly reducing two of these biases, namely, those in daytime shortwave radiation and daytime sensible heat flux. Also, CPS slightly reduces a third bias in nighttime incoming longwave radiation. The daytime improvements can be attributed partially to the switch from parameterized to explicit convection, the associated improvement in the simulation of afternoon convective clouds, and resulting surface energy budget and atmospheric feedbacks. Also responsible for the improvements during daytime is a better representation of surface heterogeneity and thus, surface roughness. Meanwhile, the modest nighttime longwave improvement can be attributed to increased vertical atmospheric resolution. However, the model still fails at reproducing the magnitude of the observed nighttime longwave difference. One possible explanation for this persistent bias is the nighttime radiative effect of biogenic volatile organic compound emissions over the forest site. A correlation between estimated emission rates and the observed nighttime longwave difference, as well as the persistence of the longwave bias provide support for this hypothesis. However, more research is needed to conclusively determine if the effect indeed exists.

The ecological impacts of nighttime light pollution: a mechanistic appraisal.

PubMed

Gaston, Kevin J; Bennie, Jonathan; Davies, Thomas W; Hopkins, John

2013-11-01

The ecological impacts of nighttime light pollution have been a longstanding source of concern, accentuated by realized and projected growth in electrical lighting. As human communities and lighting technologies develop, artificial light increasingly modifies natural light regimes by encroaching on dark refuges in space, in time, and across wavelengths. A wide variety of ecological implications of artificial light have been identified. However, the primary research to date is largely focused on the disruptive influence of nighttime light on higher vertebrates, and while comprehensive reviews have been compiled along taxonomic lines and within specific research domains, the subject is in need of synthesis within a common mechanistic framework. Here we propose such a framework that focuses on the cross-factoring of the ways in which artificial lighting alters natural light regimes (spatially, temporally, and spectrally), and the ways in which light influences biological systems, particularly the distinction between light as a resource and light as an information source. We review the evidence for each of the combinations of this cross-factoring. As artificial lighting alters natural patterns of light in space, time and across wavelengths, natural patterns of resource use and information flows may be disrupted, with downstream effects to the structure and function of ecosystems. This review highlights: (i) the potential influence of nighttime lighting at all levels of biological organisation (from cell to ecosystem); (ii) the significant impact that even low levels of nighttime light pollution can have; and (iii) the existence of major research gaps, particularly in terms of the impacts of light at population and ecosystem levels, identification of intensity thresholds, and the spatial extent of impacts in the vicinity of artificial lights. © 2013 The Authors. Biological Reviews © 2013 Cambridge Philosophical Society.

Night shift work and hormone levels in women.

PubMed

Davis, Scott; Mirick, Dana K; Chen, Chu; Stanczyk, Frank Z

2012-04-01

Night shift work may disrupt the normal nocturnal rise in melatonin, resulting in increased breast cancer risk, possibly through increased reproductive hormone levels. We investigated whether night shift work is associated with decreased levels of urinary 6-sulfatoxymelatonin, the primary metabolite of melatonin, and increased urinary reproductive hormone levels. Participants were 172 night shift and 151 day shift-working nurses, aged 20-49 years, with regular menstrual cycles. Urine samples were collected throughout work and sleep periods and assayed for 6-sulfatoxymelatonin, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estrone conjugate (E1C). 6-Sulfatoxymelatonin levels were 62% lower and FSH and LH were 62% and 58% higher, respectively, in night shift-working women during daytime sleep than in day shift-working women during nighttime sleep (P ≤ 0.0001). Nighttime sleep on off-nights was associated with 42% lower 6-sulfatoxymelatonin levels among the night shift workers, relative to the day shift workers (P < 0.0001); no significant differences in LH or FSH were observed. 6-Sulfatoxymelatonin levels during night work were approximately 69% lower and FSH and LH were 35% and 38% higher, compared with day shift workers during nighttime sleep. No differences in E1C levels between night and day shift workers were observed. Within night shift workers, 6-sulfatoxymelatonin levels were lower and reproductive hormone levels were higher during daytime sleep and nighttime work, relative to nighttime sleep (P < 0.05). These results indicate that night shift workers have substantially reduced 6-sulfatoxymelatonin levels during night work and daytime sleep and that levels remain low even when a night shift worker sleeps at night. Shift work could be an important risk factor for many other cancers in addition to breast cancer. ©2012 AACR.

Impaired endogenous nighttime melatonin secretion relates to intrarenal renin-angiotensin system activation and renal damage in patients with chronic kidney disease.

PubMed

Ishigaki, Sayaka; Ohashi, Naro; Isobe, Shinsuke; Tsuji, Naoko; Iwakura, Takamasa; Ono, Masafumi; Sakao, Yukitoshi; Tsuji, Takayuki; Kato, Akihiko; Miyajima, Hiroaki; Yasuda, Hideo

2016-12-01

Activation of the intrarenal renin-angiotensin system (RAS) plays a critical role in the pathophysiology of chronic kidney disease (CKD) and hypertension. The circadian rhythm of intrarenal RAS activation leads to renal damage and hypertension, which are associated with diurnal blood pressure (BP) variation. The activation of intrarenal RAS following reactive oxygen species (ROS) activation, sympathetic hyperactivity and nitric oxide (NO) inhibition leads to the development of renal damage. Melatonin is a hormone regulating the circadian rhythm, and has multiple functions such as anti-oxidant and anti-adrenergic effects and enhancement of NO bioavailability. Nocturnal melatonin concentrations are lower in CKD patients. However, it is not known if impaired endogenous melatonin secretion is related to BP, intrarenal RAS, or renal damage in CKD patients. We recruited 53 CKD patients and conducted 24-h ambulatory BP monitoring. urine was collected during the daytime and nighttime. We investigated the relationship among the melatonin metabolite urinary 6-sulphatoxymelatonin (U-aMT6s), BP, renal function, urinary angiotensinogen (U-AGT), and urinary albumin (U-Alb). Patients' U-aMT6s levels were significantly and negatively correlated with clinical parameters such as renal function, systolic BP, U-AGT, and U-Alb, during both day and night. Multiple regression analyses for U-aMT6s levels were performed using age, gender, renal function, and each parameter (BPs, U-AGT or U-Alb), at daytime and nighttime. U-aMT6s levels were significantly associated with U-AGT (β = -0.31, p = 0.044) and U-Alb (β = -0.25, p = 0.025) only at night. Impaired nighttime melatonin secretion may be associated with nighttime intrarenal RAS activation and renal damage in CKD patients.

Plasma renin activity to plasma aldosterone concentration ratio correlates with night-time and pulse pressures in essential hypertensive patients treated with angiotensin-converting enzyme inhibitors/AT1 blockers.

PubMed

Spannella, Francesco; Giulietti, Federico; Balietti, Paolo; Borioni, Elisabetta; Lombardi, Francesca E; Ricci, Maddalena; Cocci, Guido; Landi, Laura; Sarzani, Riccardo

2017-11-01

Angiotensin-converting enzyme inhibitors (ACE-I) and AT1 blockers (ARB) are commonly used antihypertensive drugs, but several factors may affect their effectiveness. We evaluated the associations between ambulatory blood pressure (BP) monitoring (ABPM) parameters and plasma renin activity (PRA)-to-plasma aldosterone concentration (PAC) ratio (RAR) to test renin-angiotensin-aldosterone system inhibition in essential hypertensive patients treated with ACE-I or ARB for at least 12 months. We evaluated 194 consecutive patients referred to our Hypertension Centre. ABPM, PRA and PAC tests were performed without any changes in drug therapy. RAR, PRA and PAC tertiles were considered for the analyses. Mean age: 57.4 ± 12.0 years; male prevalence: 63.9%. No differences between RAR tertiles regarding the use of ACE-I or ARB (P = 0.385), as well as the other antihypertensive drug classes, were found. A reduction of all ABPM values considered (24-h BP, daytime BP and night-time BP and 24-h pulse pressure (PP), daytime PP and night-time PP) and a better BP control were observed at increasing RAR tertiles, with an odds ratio = 0.12 to be not controlled during night-time period for patients in the third tertile compared with patients in the first tertile (P < 0.001). This association remained significant even after adjusting for 24-h BP control. All the associations were also confirmed for PRA tertiles, but not for PAC tertiles. Higher RAR values indicate effective renin-angiotensin-aldosterone system inhibition and lower night-time and pulse pressures in real-life clinical practice. It could be a useful biomarker in the management of essential hypertensive patients treated with ACE-I or ARB.

New Model of the night-time CO2 4.3 µm emissions in the mesosphere/lower thermosphere

NASA Astrophysics Data System (ADS)

Panka, P.; Kutepov, A. A.; Kalogerakis, K. S.; Janches, D.; Russell, J. M., III; Rezac, L.; Feofilov, A.; Mlynczak, M. G.; Yiğit, E.

2016-12-01

We present a new non-LTE model of the night-time CO2 4.3 µm emissions in the MLT which accounts for various mechanisms of the non-thermal excitation of CO2 molecules. We pay specific attention to the transfer of vibrational energy of OH(v), produced in the chemical reaction H + O3, to the CO2(v3) vibrational mode. Two energy transfer channels are studied: 1) the "direct" mechanism, OH(v)→N2(v)→CO2(v3)→4.3 µm, suggested by Kumer et al, [1978], and 2) the new "indirect" mechanism, OH(v)→O(1D)→N2(v)→CO2(ν3)→4.3 µm, recently suggested by Sharma et al. [2015]. We show that for various seasonal scenarios above 75 km, the "direct" mechanism alone under-predicts the observed radiance between 30-70%, from 60°S-80°N. However, considering both the "direct" and "indirect" mechanism brings differences between simulated and measured nighttime SABER 4.3 µm limb radiances down to ±10% from 75-85 km and ±20% from 85-110km for the same region. These results suggest that the important mechanism of the nighttime 4.3 µm emission generation, which was missing in previous models [Lopez-Puertas and Taylor, 2001, Lopez-Puertas et al, 2004], has finally been found. This is an important step towards developing the algorithm suitable for retrieving CO2 densities in the MLT from nighttime limb radiances obtained by SABER, which has been taking continuous measurements for the past 15 years.

Night-time lights: A global, long term look at links to socio-economic trends

PubMed Central

Zavala-Araiza, Daniel; Wagner, Gernot

2017-01-01

We use a parallelized spatial analytics platform to process the twenty-one year totality of the longest-running time series of night-time lights data—the Defense Meteorological Satellite Program (DMSP) dataset—surpassing the narrower scope of prior studies to assess changes in area lit of countries globally. Doing so allows a retrospective look at the global, long-term relationships between night-time lights and a series of socio-economic indicators. We find the strongest correlations with electricity consumption, CO2 emissions, and GDP, followed by population, CH4 emissions, N2O emissions, poverty (inverse) and F-gas emissions. Relating area lit to electricity consumption shows that while a basic linear model provides a good statistical fit, regional and temporal trends are found to have a significant impact. PMID:28346500

Equatorial Enhancement of the Nighttime OH Mesospheric Infrared Airglow

NASA Technical Reports Server (NTRS)

Baker, D. J.; Mlynczak, M. G.; Russell, J. M.

2007-01-01

Global measurements of the hydroxyl mesospheric airglow over an extended period of time have been made possible by the NASA SABER infrared sensor aboard the TIMED satellite which has been functioning since December of 2001. The orbital mission has continued over a significant portion of a solar cycle. Experimental data from SABER for several years have exhibited equatorial enhancements of the nighttime mesospheric OH (delta v = 2) airglow layer consistent with the high average diurnal solar flux. The brightening of the OH airglow typically means more H + O3 is being reacted. At both the spring and autumn seasonal equinoxes when the equatorial solar UV irradiance mean is greatest, the peak volume emission rate (VER) of the nighttime Meinel infrared airglow typically appears to be both significantly brighter plus lower in altitude by several kilometres at low latitudes compared with midlatitude findings.

Frequency of College Students' Night-Sky Watching Behaviors

ERIC Educational Resources Information Center

Kelly, William E.; Kelly, Kathryn E.; Batey, Jason

2006-01-01

College students (N = 112) completed the Noctcaelador Inventory, a measure of psychological attachment to the night-sky, and estimated various night-sky watching related activities: frequency and duration of night-sky watching, astro-tourism, ownership of night-sky viewing equipment, and attendance of observatories or planetariums. The results…

Sky online: linking amateur and professional astronomers on the world wide web

NASA Astrophysics Data System (ADS)

Fienberg, Richard Tresch

SKY Online is the World Wide Web site of Sky Publishing Corporation, publisher of Sky & Telescope magazine. Conceived mainly as an electronic extension of the company's marketing and promotion efforts, SKY Online has also proven to be a useful tool for communication between amateur and professional astronomers.

The Sky This Week, 2016 January 19 - 26 - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 January 19 - 26 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky This Week, 2016 January 19 - 26 Info The Sky This Week, 2016 January 19 - 26 See all the bright planets

The Sky This Week, 2016 April 19 - 26 - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 April 19 - 26 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky This Week, 2016 April 19 - 26 Info The Sky This Week, 2016 April 19 - 26 A bright and speedy star

The Sky This Week, 2015 December 8 - 15 - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2015 December 8 - 15 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky This Week, 2015 December 8 - 15 Info The Sky This Week, 2015 December 8 - 15 The year's best meteor

Custom Sky-Image Mosaics from NASA's Information Power Grid

NASA Technical Reports Server (NTRS)

Jacob, Joseph; Collier, James; Craymer, Loring; Curkendall, David

2005-01-01

yourSkyG is the second generation of the software described in yourSky: Custom Sky-Image Mosaics via the Internet (NPO-30556), NASA Tech Briefs, Vol. 27, No. 6 (June 2003), page 45. Like its predecessor, yourSkyG supplies custom astronomical image mosaics of sky regions specified by requesters using client computers connected to the Internet. Whereas yourSky constructs mosaics on a local multiprocessor system, yourSkyG performs the computations on NASA s Information Power Grid (IPG), which is capable of performing much larger mosaicking tasks. (The IPG is high-performance computation and data grid that integrates geographically distributed 18 NASA Tech Briefs, September 2005 computers, databases, and instruments.) A user of yourSkyG can specify parameters describing a mosaic to be constructed. yourSkyG then constructs the mosaic on the IPG and makes it available for downloading by the user. The complexities of determining which input images are required to construct a mosaic, retrieving the required input images from remote sky-survey archives, uploading the images to the computers on the IPG, performing the computations remotely on the Grid, and downloading the resulting mosaic from the Grid are all transparent to the user

Nighttime view of Apollo 9 space vehicle at Pad A, Launch Complex 39

NASA Image and Video Library

1969-02-23

S69-25879 (23 Feb. 1969) --- Nighttime view of the 363-feet-high Apollo 9 space vehicle at Pad A, Launch Complex 39, Kennedy Space Center, during preparations for the scheduled 10-day Earth-orbital space mission. The crew of the Apollo 9 (Spacecraft 104/Lunar Module 3/Saturn 504) space flight will be astronauts James A. McDivitt, David R. Scott, and Russell L. Schweickart.

Inhibition of flowering 'Arbequina' olives from chilling at lower temperatures

USDA-ARS?s Scientific Manuscript database

The effect of four nighttime chilling temperatures on the induction of flowering in ‘Arbequina’ olives was investigated. Daytime temperature was kept at 17.5 ± 0.8°C (8 hrs) while nighttime temperatures (8 hrs ) were maintained at 7.8 ± 0.5, 4.4 ± 0.5, 2.2 ± 0.5, or -1.2 ± 0.6°C; transition from da...

Long lifetime, low intensity light source for use in nighttime viewing of equipment maps and other writings

DOEpatents

Frank, Alan M.; Edwards, William R.

1983-01-01

A long-lifetime light source with sufficiently low intensity to be used for reading a map or other writing at nighttime, while not obscuring the user's normal night vision. This light source includes a diode electrically connected in series with a small power source and a lens properly positioned to focus at least a portion of the light produced by the diode.

Sleep quality and respiratory function in children with severe cerebral palsy using night-time postural equipment: a pilot study.

PubMed

Hill, Catherine M; Parker, Rachel C; Allen, Penny; Paul, Annette; Padoa, Kathryn A

2009-11-01

Night-time postural equipment (NTPE) prevents contractures and hip subluxation in children with severe physical disabilities. However, impact on sleep quality and respiratory function has not been objectively studied. Ten children with severe cerebral palsy (CP), mean age of 10.9 (range: 5.3-16.7) years, were recruited from a community population. Polysomnography was undertaken on two nights, once with the child sleeping in their NTPE and once sleeping unsupported. Randomization to first night condition controlled for first night effects. Night-time postural equipment use was associated with higher mean overnight oxygen saturation for three children but lower values for six children compared with sleeping unsupported. There were no differences in sleep quality between the conditions. The study group had lower overnight oxyhaemoglobin saturation values, less rapid eye movement (REM) sleep and higher arousal indices compared with typically developing children. This pilot study indicated that children with severe CP risk respiratory compromise in sleep irrespective of positioning. Further study will determine if the observed trend for mean overnight oxygen saturation to be lower within positioning equipment reflects random night-to-night variation or is related to equipment use. We suggest that respiratory function is assessed when determining optimal positioning for children using night-time positioning equipment.

Anomalous meridional thermospheric neutral winds in the AE-E NATE data: Effects of the equatorial nighttime pressure bulge

NASA Technical Reports Server (NTRS)

Goembel, L.; Herrero, F. A.

1995-01-01

The work described here makes it possible to identify anomalous wind behavior such as the nighttime meridional wind abatements that occur at F-region heights. A new analysis technique uses a simple empirical wind model to simulate measurements of 'normal' winds (as measured by the Neutral Atmosphere and Temperature Experiment (NATE) that flew on the Atmosphere Explorer-E (AE-E)) to highlight anomalous wind measurements made by the satellite while in circular orbits at 270-290 km altitude. Our approach is based on the recognition that the 'in orbit' wind variation must show the combined effects of the diurnal wind variation as seen from the ground with the latitude variation of the satellite orbit. For the data period 77250-78035 examined thus far, the wind abatement always occurred with a corresponding pressure or temperature maximum, and was detected on 12 out of the 36 nights with data. This study has revealed that the wind abatement occur only during or shortly after increases in solar extreme ultraviolet (EUV) flux, as indicated by daily radio flux measurements. In the past, nighttime wind reversals at mid-latitudes have been associated with increased geomagnetic activity. This study indicates that intensified solar EUV heating may be responsible for anomalous thermospheric nighttime winds at mid-latitudes.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Espeleta, Javier F.; Cardon, Zoe G.; Mayer, K. Ulrich

Hydro-biogeochemical processes in the rhizosphere regulate nutrient and water availability, and thus ecosystem productivity. We hypothesized that two such processes often neglected in rhizosphere models — diel plant water use and competitive cation exchange — could interact to enhance availability of K + and NH 4 +, both high-demand nutrients. A rhizosphere model with competitive cation exchange was used to investigate how diel plant water use (i.e., daytime transpiration coupled with no nighttime water use, with nighttime root water release, and with nighttime transpiration) affects competitive ion interactions and availability of K + and NH 4 +. Competitive cation exchangemore » enabled lowdemand cations that accumulate against roots (Ca 2+, Mg 2+, Na +) to desorb NH 4 + and K + from soil, generating non-monotonic dissolved concentration profiles (i.e. ‘hotspots’ 0.1–1 cm from the root). Cation accumulation and competitive desorption increased with net root water uptake. Daytime transpiration rate controlled diel variation in NH 4 + and K + aqueous mass, nighttime water use controlled spatial locations of ‘hotspots’, and day-to-night differences in water use controlled diel differences in ‘hotspot’ concentrations. Finally, diel plant water use and competitive cation exchange enhanced NH 4 + and K + availability and influenced rhizosphere concentration dynamics. Demonstrated responses have implications for understanding rhizosphere nutrient cycling and plant nutrient uptake.« less

Poverty assessment using DMSP/OLS night-time light satellite imagery at a provincial scale in China

NASA Astrophysics Data System (ADS)

Wang, Wen; Cheng, Hui; Zhang, Li

2012-04-01

All countries around the world and many international bodies, including the United Nations Development Program (UNDP), United Nations Food and Agricultural Organization (FAO), the International Fund for Agricultural Development (IFAD) and the International Labor Organization (ILO), have to eliminate rural poverty. Estimation of regional poverty level is a key issue for making strategies to eradicate poverty. Most of previous studies on regional poverty evaluations are based on statistics collected typically in administrative units. This paper has discussed the deficiencies of traditional studies, and attempted to research regional poverty evaluation issues using 3-year DMSP/OLS night-time light satellite imagery. In this study, we adopted 17 socio-economic indexes to establish an integrated poverty index (IPI) using principal component analysis (PCA), which was proven to provide a good descriptor of poverty levels in 31 regions at a provincial scale in China. We also explored the relationship between DMSP/OLS night-time average light index and the poverty index using regression analysis in SPSS and a good positive linear correlation was modelled, with R2 equal to 0.854. We then looked at provincial poverty problems in China based on this correlation. The research results indicated that the DMSP/OLS night-time light data can assist analysing provincial poverty evaluation issues.

A Lunchtime Walk in Nature Enhances Restoration of Autonomic Control during Night-Time Sleep: Results from a Preliminary Study.

PubMed

Gladwell, Valerie F; Kuoppa, Pekka; Tarvainen, Mika P; Rogerson, Mike

2016-03-03

Walking within nature (Green Exercise) has been shown to immediately enhance mental well-being but less is known about the impact on physiology and longer lasting effects. Heart rate variability (HRV) gives an indication of autonomic control of the heart, in particular vagal activity, with reduced HRV identified as a risk factor for cardiovascular disease. Night-time HRV allows vagal activity to be assessed whilst minimizing confounding influences of physical and mental activity. The aim of this study was to investigate whether a lunchtime walk in nature increases night-time HRV. Participants (n = 13) attended on two occasions to walk a 1.8 km route through a built or a natural environment. Pace was similar between the two walks. HRV was measured during sleep using a RR interval sensor (eMotion sensor) and was assessed at 1-2 h after participants noted that they had fallen asleep. Markers for vagal activity were significantly greater after the walk in nature compared to the built walk. Lunchtime walks in nature-based environments may provide a greater restorative effect as shown by vagal activity than equivalent built walks. Nature walks may improve essential recovery during night-time sleep, potentially enhancing physiological health.

Reactive nitrogen partitioning and its relationship to winter ozone events in Utah

NASA Astrophysics Data System (ADS)

Wild, R. J.; Edwards, P. M.; Bates, T. S.; Cohen, R. C.; de Gouw, J. A.; Dubé, W. P.; Gilman, J. B.; Holloway, J.; Kercher, J.; Koss, A.; Lee, L.; Lerner, B.; McLaren, R.; Quinn, P. K.; Roberts, J. M.; Stutz, J.; Thornton, J. A.; Veres, P. R.; Warneke, C.; Williams, E.; Young, C. J.; Yuan, B.; Brown, S. S.

2015-08-01

High wintertime ozone levels have been observed in the Uintah Basin, Utah, a sparsely populated rural region with intensive oil and gas operations. The reactive nitrogen budget plays an important role in tropospheric ozone formation. Measurements were taken during three field campaigns in the winters of 2012, 2013, and 2014, which experienced varying climatic conditions. Average concentrations of ozone and total reactive nitrogen were observed to be 2.5 times higher in 2013 than 2012, with 2014 an intermediate year in most respects. However, photochemically active NOx(NO+NO2), remained remarkably similar all three years. Roughly half of the more oxidized forms of nitrogen were composed of nitric acid in 2013, with nighttime nitric acid formation through heterogeneous uptake of N2O5 contributing approximately 6 times more than daytime formation. The nighttime N2O5 lifetime between the high-ozone year 2013 and the low-ozone year 2012 is lower by a factor 2.6, and much of this is due to higher aerosol surface area in the high ozone year of 2013. A box-model simulation supports the importance of nighttime chemistry on the reactive nitrogen budget, showing a large sensitivity of NOx and ozone concentrations to nighttime processes.

The Sky This Week, 2016 March 15 - 23 - Naval Oceanography Portal

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are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 March 15 - 23 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky This Week, 2016 March 15 - 23 Info The Sky This Week, 2016 March 15 - 23 The equinox and the calendar

The Sky This Week, 2016 January 5 - 12 - Naval Oceanography Portal

Science.gov Websites

are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Week, 2016 January 5 - 12 USNO Logo USNO Navigation Tour Information USNO Scientific Colloquia Sky This Week The Sky This Week, 2016 January 5 - 12 Info The Sky This Week, 2016 January 5 - 12 Count the stars in Orion for

PePSS - A portable sky scanner for measuring extremely low night-sky brightness

NASA Astrophysics Data System (ADS)

Kocifaj, Miroslav; Kómar, Ladislav; Kundracik, František

2018-05-01

A new portable sky scanner designed for low-light-level detection at night is developed and employed in night sky brightness measurements in a rural region. The fast readout, adjustable sensitivity and linear response guaranteed in 5-6 orders of magnitude makes the device well suited for narrow-band photometry in both dark areas and bright urban and suburban environments. Quasi-monochromatic night-sky brightness data are advantageous in the accurate characterization of spectral power distribution of scattered and emitted light and, also allows for the possibility to retrieve light output patterns from whole-city light sources. The sky scanner can operate in both night and day regimes, taking advantage of the complementarity of both radiance data types. Due to its inherent very high sensitivity the photomultiplier tube could be used in night sky radiometry, while the spectrometer-equipped system component capable of detecting elevated intensities is used in daylight monitoring. Daylight is a source of information on atmospheric optical properties that in turn are necessary in processing night sky radiances. We believe that the sky scanner has the potential to revolutionize night-sky monitoring systems.

Sky Detection in Hazy Image.

PubMed

Song, Yingchao; Luo, Haibo; Ma, Junkai; Hui, Bin; Chang, Zheng

2018-04-01

Sky detection plays an essential role in various computer vision applications. Most existing sky detection approaches, being trained on ideal dataset, may lose efficacy when facing unfavorable conditions like the effects of weather and lighting conditions. In this paper, a novel algorithm for sky detection in hazy images is proposed from the perspective of probing the density of haze. We address the problem by an image segmentation and a region-level classification. To characterize the sky of hazy scenes, we unprecedentedly introduce several haze-relevant features that reflect the perceptual hazy density and the scene depth. Based on these features, the sky is separated by two imbalance SVM classifiers and a similarity measurement. Moreover, a sky dataset (named HazySky) with 500 annotated hazy images is built for model training and performance evaluation. To evaluate the performance of our method, we conducted extensive experiments both on our HazySky dataset and the SkyFinder dataset. The results demonstrate that our method performs better on the detection accuracy than previous methods, not only under hazy scenes, but also under other weather conditions.

Anomalous celestial polarization caused by forest fire smoke: why do some insects become visually disoriented under smoky skies?

NASA Astrophysics Data System (ADS)

Hegedüs, Ramón; Åkesson, Susanne; Horváth, Gábor

2007-05-01

The effects of forest fire smoke on sky polarization and animal orientation are practically unknown. Using full-sky imaging polarimetry, we therefore measured the celestial polarization pattern under a smoky sky in Fairbanks, Alaska, during the forest fire season in August 2005. It is quantitatively documented here that the celestial polarization, a sky attribute that is necessary for orientation of many polarization-sensitive animal species, above Fairbanks on 17 August 2005 was in several aspects anomalous due to the forest fire smoke: (i) The pattern of the degree of linear polarization p of the reddish smoky sky differed considerably from that of the corresponding clear blue sky. (ii) Due to the smoke, p of skylight was drastically reduced (pmax≤14%, paverage≤8%). (iii) Depending on wavelength and time, the Arago, Babinet, and Brewster neutral points of sky polarization had anomalous positions. We suggest that the disorientation of certain insects observed by Canadian researchers under smoky skies during the forest fire season in August 2003 in British Columbia was the consequence of the anomalous sky polarization caused by the forest fire smoke.

Sky Detection in Hazy Image

PubMed Central

Song, Yingchao; Luo, Haibo; Ma, Junkai; Hui, Bin; Chang, Zheng

2018-01-01

Sky detection plays an essential role in various computer vision applications. Most existing sky detection approaches, being trained on ideal dataset, may lose efficacy when facing unfavorable conditions like the effects of weather and lighting conditions. In this paper, a novel algorithm for sky detection in hazy images is proposed from the perspective of probing the density of haze. We address the problem by an image segmentation and a region-level classification. To characterize the sky of hazy scenes, we unprecedentedly introduce several haze-relevant features that reflect the perceptual hazy density and the scene depth. Based on these features, the sky is separated by two imbalance SVM classifiers and a similarity measurement. Moreover, a sky dataset (named HazySky) with 500 annotated hazy images is built for model training and performance evaluation. To evaluate the performance of our method, we conducted extensive experiments both on our HazySky dataset and the SkyFinder dataset. The results demonstrate that our method performs better on the detection accuracy than previous methods, not only under hazy scenes, but also under other weather conditions. PMID:29614778

The Sky This Week, 2016 January 27 - February 2 - Naval Oceanography

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Oceanography Ice You are here: Home › USNO › News, Tours & Events › Sky This Week › The Sky This Sky This Week The Sky This Week, 2016 January 27 - February 2 Info The Sky This Week, 2016 January 27 - February 2 Lest we forget. NOFS_Winter_2016_01small.jpg Dome of the Kaj Strand 1.55-meter (61-inch

Long lifetime, low intensity light source for use in nighttime viewing of equipment maps and other writings

DOEpatents

Frank, A.M.; Edwards, W.R.

1983-10-11

A long-lifetime light source with sufficiently low intensity to be used for reading a map or other writing at nighttime, while not obscuring the user's normal night vision is disclosed. This light source includes a diode electrically connected in series with a small power source and a lens properly positioned to focus at least a portion of the light produced by the diode. 1 fig.

Urbanization Causes Increased Cloud Base Height and Decreased Fog in Coastal Southern California

NASA Technical Reports Server (NTRS)

Williams, A. Park; Schwartz, Rachel E.; Iacobellis, Sam; Seager, Richard; Cook, Benjamin I.; Still, Christopher J.; Husak, Gregory; Michaelsen, Joel

2015-01-01

Subtropical marine stratus clouds regulate coastal and global climate, but future trends in these clouds are uncertain. In coastal Southern California (CSCA), interannual variations in summer stratus cloud occurrence are spatially coherent across 24 airfields and dictated by positive relationships with stability above the marine boundary layer (MBL) and MBL height. Trends, however, have been spatially variable since records began in the mid-1900s due to differences in nighttime warming. Among CSCA airfields, differences in nighttime warming, but not daytime warming, are strongly and positively related to fraction of nearby urban cover, consistent with an urban heat island effect. Nighttime warming raises the near-surface dew point depression, which lifts the altitude of condensation and cloud base height, thereby reducing fog frequency. Continued urban warming, rising cloud base heights, and associated effects on energy and water balance would profoundly impact ecological and human systems in highly populated and ecologically diverse CSCA.

The nighttime ionosphere of Mars from Mars-4 and Mars-5 radio occultation dual-frequency measurements

NASA Technical Reports Server (NTRS)

Savich, N. A.; Samovol, V. A.; Vasilyev, M. B.; Vyshlov, A. S.; Samoznaev, L. N.; Sidorenko, A. I.; Shtern, D. Y.

1976-01-01

Dual frequency radio sounding of the Martian nighttime ionosphere was carried out during the exits from behind the planet of the Mars-4 spacecraft on February 2, 1974 and the Mars-5 spacecraft on February 18, 1974. In these experiments, the spacecraft transmitter emitted two coherent monochromatic signals in decimeter and centimeter wavelength ranges. At the Earth receiving station, the reduced phase difference (or frequencies) of these signals was measured. The nighttime ionosphere of Mars measured in both cases had a peak electron density of approximately 5 X 1,000/cu cm at an altitude of 110 to 130 km. At the times of spacecraft exit, the solar zenith angles at the point of occultation were 127 deg and 106 deg, respectively. The height profiles of electron concentration were obtained assuming spherical symmetry of the Martian ionosphere.

Napping in college students and its relationship with nighttime sleep.

PubMed

Ye, Lichuan; Hutton Johnson, Stacy; Keane, Kathleen; Manasia, Michael; Gregas, Matt

2015-01-01

Abstract. To examine the habit of napping and its relationship with nighttime sleep in college students. Four hundred and forty undergraduate students who responded to an anonymous online survey in April 2010. Three questions were asked to determine the frequency, length, and timing of napping during the past month. Sleep quality was measured by the Pittsburgh Sleep Quality Index (PSQI). The PSQI score significantly differed among self-reported nap-frequency (p=.047) and nap-length (p=.017) groups, with those who napped more than 3 times per week and those who napped more than 2 hours having the poorest sleep quality. Students who napped between 6 and 9 pm had shorter sleep on school nights compared with students in other nap-timing groups (p=.002). College students who are self-reported frequent, long, and late nappers may have a higher risk of poor nighttime sleep quality and more severe sleep deprivation.

Nighttime image dehazing using local atmospheric selection rule and weighted entropy for visible-light systems

NASA Astrophysics Data System (ADS)

Park, Dubok; Han, David K.; Ko, Hanseok

2017-05-01

Optical imaging systems are often degraded by scattering due to atmospheric particles, such as haze, fog, and mist. Imaging under nighttime haze conditions may suffer especially from the glows near active light sources as well as scattering. We present a methodology for nighttime image dehazing based on an optical imaging model which accounts for varying light sources and their glow. First, glow effects are decomposed using relative smoothness. Atmospheric light is then estimated by assessing global and local atmospheric light using a local atmospheric selection rule. The transmission of light is then estimated by maximizing an objective function designed on the basis of weighted entropy. Finally, haze is removed using two estimated parameters, namely, atmospheric light and transmission. The visual and quantitative comparison of the experimental results with the results of existing state-of-the-art methods demonstrates the significance of the proposed approach.

A feasibility study for conducting unattended night-time operations at WMKO

NASA Astrophysics Data System (ADS)

Stomski, Paul J.; Gajadhar, Sarah; Dahm, Scott; Jordan, Carolyn; Nordin, Tom

2016-08-01

In 2015, W. M. Keck Observatory conducted a study of the feasibility of conducting nighttime operations on Maunakea without any staff on the mountain. The study was motivated by the possibility of long term operational costs savings as well as other expected benefits. The goals of the study were to understand the technical feasibility and risk as well as to provide labor and cost estimates for implementation. The results of the study would be used to inform a decision about whether or not to fund and initiate a formal project aimed at the development of this new unattended nighttime operating capability. In this paper we will describe the study process as well as a brief summary of the results including the identified viable design alternative, the risk analysis, and the scope of work. We will also share the decisions made as a result of the study and current status of related follow-on activity.

Night-time lighting alters the composition of marine epifaunal communities

PubMed Central

Davies, Thomas W.; Coleman, Matthew; Griffith, Katherine M.; Jenkins, Stuart R.

2015-01-01

Marine benthic communities face multiple anthropogenic pressures that compromise the future of some of the most biodiverse and functionally important ecosystems in the world. Yet one of the pressures these ecosystems face, night-time lighting, remains unstudied. Light is an important cue in guiding the settlement of invertebrate larvae, and altering natural regimes of nocturnal illumination could modify patterns of recruitment among sessile epifauna. We present the first evidence of night-time lighting changing the composition of temperate epifaunal marine invertebrate communities. Illuminating settlement surfaces with white light-emitting diode lighting at night, to levels experienced by these communities locally, both inhibited and encouraged the colonization of 39% of the taxa analysed, including three sessile and two mobile species. Our results indicate that ecological light pollution from coastal development, shipping and offshore infrastructure could be changing the composition of marine epifaunal communities. PMID:25926694

From OLS to VIIRS, an overview of nighttime satellite aerosol retrievals using artificial light sources

NASA Astrophysics Data System (ADS)

Zhang, J.; Miller, S. D.; Reid, J. S.; Hyer, E. J.; McHardy, T. M.

2015-12-01

Compared to abundant daytime satellite-based observations of atmospheric aerosol, observations at night are relatively scarce. In particular, conventional satellite passive imaging radiometers, which offer expansive swaths of spatial coverage compared to non-scanning lidar systems, lack sensitivity to most aerosol types via the available thermal infrared bands available at night. In this talk, we make the fundamental case for the importance of nighttime aerosol information in forecast models, and the need to mitigate the existing nocturnal gap. We review early attempts at estimating nighttime aerosol optical properties using the modulation of stable artificial surface lights. Initial algorithm development using DMSP Operational Linescan System (OLS) has graduated to refined techniques based on the Suomi-NPP Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB). We present examples of these retrievals for selected cases and compare the results to available surface-based point-source validation data.

Ozone chemical equilibrium in the extended mesopause under the nighttime conditions

NASA Astrophysics Data System (ADS)

Belikovich, M. V.; Kulikov, M. Yu.; Grygalashvyly, M.; Sonnemann, G. R.; Ermakova, T. S.; Nechaev, A. A.; Feigin, A. M.

2018-01-01

For retrieval of atomic oxygen and atomic hydrogen via ozone observations in the extended mesopause region (∼70-100 km) under nighttime conditions, an assumption on photochemical equilibrium of ozone is often used in research. In this work, an assumption on chemical equilibrium of ozone near mesopause region during nighttime is proofed. We examine 3D chemistry-transport model (CTM) annual calculations and determine the ratio between the correct (modeled) distributions of the O3 density and its equilibrium values depending on the altitude, latitude, and season. The results show that the retrieval of atomic oxygen and atomic hydrogen distributions using an assumption on ozone chemical equilibrium may lead to large errors below ∼81-87 km. We give simple and clear semi-empirical criterion for practical utilization of the lower boundary of the area with ozone's chemical equilibrium near mesopause.

Evaluation of Clear Sky Models for Satellite-Based Irradiance Estimates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sengupta, Manajit; Gotseff, Peter

2013-12-01

This report describes an intercomparison of three popular broadband clear sky solar irradiance model results with measured data, as well as satellite-based model clear sky results compared to measured clear sky data. The authors conclude that one of the popular clear sky models (the Bird clear sky model developed by Richard Bird and Roland Hulstrom) could serve as a more accurate replacement for current satellite-model clear sky estimations. Additionally, the analysis of the model results with respect to model input parameters indicates that rather than climatological, annual, or monthly mean input data, higher-time-resolution input parameters improve the general clear skymore » model performance.« less

For Spacious Skies: A Teacher's Guide. An Interdisciplinary Approach to the Sky.

ERIC Educational Resources Information Center

For Spacious Skies, Inc., Lexington, MA.

Despite the fact that the sky is the most dominant feature of our surroundings, it plays the role of an unseen background for many objects. It is the intent of this guide to bring about an awareness of the sky to young people. Topics for activities include: (1) "Sky Awareness"; (2) "Compass"; (3) "Hand Lens"; (4)…

yourSky: Custom Sky-Image Mosaics via the Internet

NASA Technical Reports Server (NTRS)

Jacob, Joseph

2003-01-01

yourSky (http://yourSky.jpl.nasa.gov) is a computer program that supplies custom astronomical image mosaics of sky regions specified by requesters using client computers connected to the Internet. [yourSky is an upgraded version of the software reported in Software for Generating Mosaics of Astronomical Images (NPO-21121), NASA Tech Briefs, Vol. 25, No. 4 (April 2001), page 16a.] A requester no longer has to engage in the tedious process of determining what subset of images is needed, nor even to know how the images are indexed in image archives. Instead, in response to a requester s specification of the size and location of the sky area, (and optionally of the desired set and type of data, resolution, coordinate system, projection, and image format), yourSky automatically retrieves the component image data from archives totaling tens of terabytes stored on computer tape and disk drives at multiple sites and assembles the component images into a mosaic image by use of a high-performance parallel code. yourSky runs on the server computer where the mosaics are assembled. Because yourSky includes a Web-interface component, no special client software is needed: ordinary Web browser software is sufficient.

Retrieving cirrus microphysical properties from stellar aureoles

NASA Astrophysics Data System (ADS)

DeVore, J. G.; Kristl, J. A.; Rappaport, S. A.

2013-06-01

The aureoles around stars caused by thin cirrus limit nighttime measurement opportunities for ground-based astronomy, but can provide information on high-altitude ice crystals for climate research. In this paper we attempt to demonstrate quantitatively how this works. Aureole profiles can be followed out to ~0.2° from stars and ~0.5° from Jupiter. Interpretation of diffracted starlight is similar to that for sunlight, but emphasizes larger particles. Stellar diffraction profiles are very distinctive, typically being approximately flat out to a critical angle followed by gradually steepening power-law falloff with slope less steep than -3. Using the relationship between the phase function for diffraction and the average Fourier transform of the projected area of complex ice crystals, we show that defining particle size in terms of average projected area normal to the propagation direction of the starlight leads to a simple, analytic approximation representing large-particle diffraction that is nearly independent of crystal habit. A similar analytic approximation for the diffraction aureole allows it to be separated from the point spread function and the sky background. Multiple scattering is deconvolved using the Hankel transform leading to the diffraction phase function. Application of constrained numerical inversion to the phase function then yields a solution for the particle size distribution in the range between ~50 μm and ~400 μm. Stellar aureole measurements can provide one of the very few, as well as least expensive, methods for retrieving cirrus microphysical properties from ground-based observations.

WINDII airglow observations of wave superposition and the possible association with historical "bright nights"

NASA Astrophysics Data System (ADS)

Shepherd, G. G.; Cho, Y.-M.

2017-07-01

Longitudinal variations of airglow emission rate are prominent in all midlatitude nighttime O(1S) lower thermospheric data obtained with the Wind Imaging Interferometer (WINDII) on the Upper Atmosphere Research Satellite (UARS). The pattern generally appears as a combination of zonal waves 1, 2, 3, and 4 whose phases propagate at different rates. Sudden localized enhancements of 2 to 4 days duration are sometimes evident, reaching vertically integrated emission rates of 400 R, a factor of 10 higher than minimum values for the same day. These are found to occur when the four wave components come into the same phase at one longitude. It is shown that these highly localized longitudinal maxima are consistent with the historical phenomena known as "bright nights" in which the surroundings of human dark night observers were seen to be illuminated by this enhanced airglow.