WorldWideScience

Sample records for repeller night light

  1. Traffic Light Detection at Night

    DEFF Research Database (Denmark)

    Jensen, Morten Bornø; Philipsen, Mark Philip; Bahnsen, Chris

    2015-01-01

    of three detectors based on heuristic models and one learning-based detector. Evaluation is done on night-time data from the public LISA Traffic Light Dataset. The learning-based detector out- performs the model-based detectors in both precision and recall. The learning-based detector achieves an average......Traffic light recognition (TLR) is an integral part of any in- telligent vehicle, it must function both at day and at night. However, the majority of TLR research is focused on day-time scenarios. In this paper we will focus on detection of traffic lights at night and evalu- ate the performance...

  2. Nature's Late-Night Light Shows

    Science.gov (United States)

    Peterson, Carolyn Collins

    2002-09-01

    In addition to stars and planets, there are other interesting lights to be seen in the night sky. The northern and southern lights, called the aurora borealis and aurora australis, are created by charged particles from the Sun reacting in Earth's magnetic field. Night-shining clouds or noctilucent clouds appear at evening twilight as a result of water vapor in the polar mesosphere. Zodiacal light can be seen stretching up from the horizon after sunset or before sunrise.

  3. Shedding Light on Night Learning.

    Science.gov (United States)

    Horwood, Bert

    1986-01-01

    Shows how darkness and night provide a potentially excellent arena for experiential learning opportunities. Recommends learning must be gradual, beginning with appreciation and allaying fear of the dark. Suggests sensory activities, hikes, games, aquatic activities, ecological simulations, historical presentations, and writing or reciting poetry.…

  4. Early Birds by Light at Night

    NARCIS (Netherlands)

    Jong, De Maaike; Caro, Samuel P.; Gienapp, Phillip; Spoelstra, Kamiel; Visser, Marcel E.

    2017-01-01

    Artificial light at night disturbs the daily rhythms of many organisms. To what extent this disturbance depends on the intensity and spectral composition of light remain obscure. Here, we measured daily activity patterns of captive blue tits (Cyanistes caeruleus) exposed to similar intensities of

  5. Artificial night lighting inhibits feeding in moths

    NARCIS (Netherlands)

    Langevelde, Van Frank; Grunsven, Van Roy H.A.; Veenendaal, Elmar M.; Fijen, Thijs P.M.

    2017-01-01

    One major, yet poorly studied, change in the environment is nocturnal light pollution, which strongly alters habitats of nocturnally active species. Artificial night lighting is often considered as driving force behind rapid moth population declines in severely illuminated countries. To understand

  6. PAVE LOW III: interior lighting reconfiguration for night lighting and night vision goggle compatibility.

    Science.gov (United States)

    Task, H L; Griffin, L L

    1982-12-01

    The PAVE LOW III aircraft is a modified HH-53H helicopter that has a low altitude--below 30.48 m (100 ft)--night/day rescue mission. The desired night flying configuration is for the pilot to wear night vision goggles (NVGs) to fly the aircraft while the copilot, without NVGs, observes the video display and monitors the aircraft instruments. The problems of NVG incompatibility in the cockpit were successfully countered using several light control techniques. The light control modifications were evaluated on the ground in the PAVE LOW III helicopter at Kirtland AFB in April, 1980, by PAVE LOW instructor pilots. The evaluation results were extremely positive.

  7. Artificial light at night inhibits mating in a geometrid moth

    NARCIS (Netherlands)

    van Geffen, Koert G.; van Eck, Emiel; de Boer, Rens A.; van Grunsven, Roy H. A.; Salis, Lucia; Berendse, Frank; Veenendaal, Elmar M.

    Levels of artificial night lighting are increasing rapidly worldwide, subjecting nocturnal organisms to a major change in their environment. Many moth species are strongly attracted to sources of artificial night lighting, with potentially severe, yet poorly studied, consequences for development,

  8. Do wild great tits avoid exposure to light at night?

    NARCIS (Netherlands)

    De Jong, M.; Ouyang, Jenny; van Grunsven, Roy H. A.; Visser, M.E.; Spoelstra, K.

    2016-01-01

    Studies of wild populations have provided important insights into the effects of artificial light at night on organisms, populations and ecosystems. However, in most studies the exact amount of light at night individuals are exposed to remains unknown. Individuals can potentially control their night

  9. Do Wild Great Tits Avoid Exposure to Light at Night?

    NARCIS (Netherlands)

    de Jong, Maaike; Ouyang, Jenny Q; van Grunsven, Roy H A; Visser, Marcel E; Spoelstra, Kamiel

    2016-01-01

    Studies of wild populations have provided important insights into the effects of artificial light at night on organisms, populations and ecosystems. However, in most studies the exact amount of light at night individuals are exposed to remains unknown. Individuals can potentially control their night

  10. Forecasting Urban Expansion Based on Night Lights

    Science.gov (United States)

    Stathakis, D.

    2016-06-01

    Forecasting urban expansion models are a very powerful tool in the hands of urban planners in order to anticipate and mitigate future urbanization pressures. In this paper, a linear regression forecasting urban expansion model is implemented based on the annual composite night lights time series available from National Oceanic and Atmospheric Administration (NOAA). The product known as 'stable lights' is used in particular, after it has been corrected with a standard intercalibration process to reduce artificial year-to-year fluctuations as much as possible. Forecasting is done for ten years after the end of the time series. Because the method is spatially explicit the predicted expansion trends are relatively accurately mapped. Two metrics are used to validate the process. The first one is the year-to-year Sum of Lights (SoL) variation. The second is the year-to-year image correlation coefficient. Overall it is evident that the method is able to provide an insight on future urbanization pressures in order to be taken into account in planning. The trends are quantified in a clear spatial manner.

  11. Night lights and regional income inequality in Africa

    DEFF Research Database (Denmark)

    Mveyange, Anthony Francis

    Estimating regional income inequality in Africa has been challenging due to the lack of reliable and consistent sub-national income data. I employ night lights data to circumvent this limitation. I find significant and positive associations between regional inequality visible through night lights...... and income in Africa. Thus, in the absence of income data, we can construct regional inequality proxies using night lights data. Further investigation on the night lights-based regional inequality trends reveals two main findings: first, increasing regional inequality trends between 1992 and 2003; and second......, declining regional inequality trends between 2004 and 2012....

  12. The Ecological Implications of Light at Night (LAN)

    Science.gov (United States)

    Henshaw, Colin

    2015-08-01

    Summary: Light at night (LAN) is now an established environmental problem, not only for astronomers but for the population at large. It has serious ecological effects that are wide ranging, and its environmental effects may be more serious than ever imagined. The ecological and environmental consequences are examined and emphasis is stressed on resolving the problem before it is too late.Introduction: A casual glance at NASA images of the Earth at night1 reveals the lights of thousands of cities. The larger cities will contain millions of street lights, along with commercial, sports and decorative lighting. Most of these lights are on all night, every night, three hundred and sixty-five nights a year, (fig 1), so they must be having a measurable ecological and environmental effect. The most obvious effect of all this excessive lighting is the light pollution suffered by astronomers.

  13. Do wild great tits avoid exposure to light at night?

    NARCIS (Netherlands)

    De Jong, M.; Ouyang, Jenny; van Grunsven, Roy H. A.; Visser, M.E.; Spoelstra, K.

    2016-01-01

    Studies of wild populations have provided important insights into the effects of artificial light at night on organisms, populations and ecosystems. However, in most studies the exact amount of light at night individuals are exposed to remains unknown. Individuals can potentially control their

  14. Do wild great tits avoid exposure to light at night?

    NARCIS (Netherlands)

    Jong, De Maaike; Ouyang, Jenny Q.; Grunsven, van Roy H.A.; Visser, Marcel E.; Spoelstra, Kamiel

    2016-01-01

    Studies of wild populations have provided important insights into the effects of artificial light at night on organisms, populations and ecosystems. However, in most studies the exact amount of light at night individuals are exposed to remains unknown. Individuals can potentially control their ni

  15. Do Wild Great Tits Avoid Exposure to Light at Night?

    Science.gov (United States)

    de Jong, Maaike; Ouyang, Jenny Q; van Grunsven, Roy H A; Visser, Marcel E; Spoelstra, Kamiel

    2016-01-01

    Studies of wild populations have provided important insights into the effects of artificial light at night on organisms, populations and ecosystems. However, in most studies the exact amount of light at night individuals are exposed to remains unknown. Individuals can potentially control their nighttime light exposure by seeking dark spots within illuminated areas. This uncertainty makes it difficult to attribute effects to a direct effect of light at night, or to indirect effects, e.g., via an effect of light at night on food availability. In this study, we aim to quantify the nocturnal light exposure of wild birds in a previously dark forest-edge habitat, experimentally illuminated with three different colors of street lighting, in comparison to a dark control. During two consecutive breeding seasons, we deployed male great tits (Parus major) with a light logger measuring light intensity every five minutes over a 24h period. We found that three males from pairs breeding in brightly illuminated nest boxes close to green and red lamp posts, were not exposed to more artificial light at night than males from pairs breeding further away. This suggests, based on our limited sample size, that these males could have been avoiding light at night by choosing a roosting place with a reduced light intensity. Therefore, effects of light at night previously reported for this species in our experimental set-up might be indirect. In contrast to urban areas where light is omnipresent, bird species in non-urban areas may evade exposure to nocturnal artificial light, thereby avoiding direct consequences of light at night.

  16. Do Wild Great Tits Avoid Exposure to Light at Night?

    Directory of Open Access Journals (Sweden)

    Maaike de Jong

    Full Text Available Studies of wild populations have provided important insights into the effects of artificial light at night on organisms, populations and ecosystems. However, in most studies the exact amount of light at night individuals are exposed to remains unknown. Individuals can potentially control their nighttime light exposure by seeking dark spots within illuminated areas. This uncertainty makes it difficult to attribute effects to a direct effect of light at night, or to indirect effects, e.g., via an effect of light at night on food availability. In this study, we aim to quantify the nocturnal light exposure of wild birds in a previously dark forest-edge habitat, experimentally illuminated with three different colors of street lighting, in comparison to a dark control. During two consecutive breeding seasons, we deployed male great tits (Parus major with a light logger measuring light intensity every five minutes over a 24h period. We found that three males from pairs breeding in brightly illuminated nest boxes close to green and red lamp posts, were not exposed to more artificial light at night than males from pairs breeding further away. This suggests, based on our limited sample size, that these males could have been avoiding light at night by choosing a roosting place with a reduced light intensity. Therefore, effects of light at night previously reported for this species in our experimental set-up might be indirect. In contrast to urban areas where light is omnipresent, bird species in non-urban areas may evade exposure to nocturnal artificial light, thereby avoiding direct consequences of light at night.

  17. Night-Lighting as a Waterfowl Capture Technique

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In recent years considerable experimentation with the night-lighting technique for capturing waterfowl has been conducted in the United State s and Canada....

  18. Light Pollution Awareness through Globe at Night & IYL2015

    Science.gov (United States)

    Walker, Constance E.

    2015-01-01

    The International Astronomical Union (IAU) will be coordinating extensive activities to raise awareness of light pollution through running the Cosmic Light theme of the International Year of Light (IYL2015) and by partnering in particular with the popular Globe at Night program.Globe at Night (www.globeatnight.org) is an international campaign to raise public awareness of the impact of light pollution by having people measure night-sky brightness and submit observations in real-time with smart phone or later with a computer. In 2015, Globe at Night will run for 10-nights each month, an hour after sunset til before the Moon rises. Students can use the data to monitor levels of light pollution around the world, as well as understand light pollution's effects on energy consumption, plants, wildlife, human health and our ability to enjoy a starry night sky.Since its inception in 2006, more than 115,000 measurements from 115 countries have been reported. The last 9 years of data can be explored with Globe at Night's interactive world map or with the 'map app' to view a particular area. A spreadsheet of the data is downloadable from any year. One can compare Globe at Night data with a variety of other databases to see, for example, how light pollution affects the foraging habits of bats.To encourage public participation in Globe at Night during IYL2015, each month will target an area of the world that habitually contributes during that time. Special concerns for how light pollution affects that area and solutions will be featured on the Globe at Night website (www.globeatnight.org), through its Facebook page, in its newsletter or in the 365DaysofAstronomy.org podcasts.Twice during IYL there will be a global Flash Mob event, one on Super Pi Day (March 14, 2015) and a second in mid-September, where the public will be invited to take night-sky brightness measurements en masse. In April, the International Dark-Sky Week hosted by the International Dark-Sky Association will be

  19. Low light comparison of target visibility with night vision goggles

    Science.gov (United States)

    Craig, Gregory; Brulotte, Michel; Carignan, Stephan; Macuda, Todd; Jennings, Sion

    2008-04-01

    Different night vision goggle image intensification technologies were tested to compare goggle performance in low light conditions. A total of four different night vision goggles were tested in a laboratory dark room. The laboratory tests consisted of viewing Landolt acuity stimuli of different contrast levels with each set of goggles and without the goggles in full light conditions (baseline performance). The results from the laboratory testing indicated that there were significant differences in acuity between the NVGs, particularly for low contrast targets. These data suggest that NVG standards developed using high contrast targets, even in low light conditions may not provide the full story of how the NVG will perform in flight.

  20. Light-induced melatonin suppression at night after exposure to different wavelength composition of morning light.

    Science.gov (United States)

    Kozaki, Tomoaki; Kubokawa, Ayaka; Taketomi, Ryunosuke; Hatae, Keisuke

    2016-03-11

    Bright nocturnal light has been shown to suppress melatonin secretion. However, bright light exposure during the day might reduce light-induced melatonin suppression at night. The human circadian system is sensitive to short wavelength light. This study evaluated the preventive effect of different wavelengths of daytime light on light-induced melatonin suppression at night. Twelve male subjects were exposed to various light conditions (dim, white, and bluish white light) between the hours of 09:00 and 10:30 (daytime light conditions). They were then exposed to light (300lx) again between 01:00 and 02:30 (night-time light exposure). Subjects provided saliva samples before (00:55) and after night-time light exposure (02:30). A two-tailed paired t-test yielded significant decrements in melatonin concentrations after night-time light exposure under daytime dim and white light conditions. No significant differences were found in melatonin concentrations between pre- and post-night-time light exposure with bluish-white light. Present findings suggest that daytime blue light exposure has an acute preventive impact on light-induced melatonin suppression in individuals with a general life rhythm (sleep/wake schedule). These findings may be useful for implementing artificial light environments for humans in, for example, hospitals and underground shopping malls to reduce health risks.

  1. Session 21.5 - Light at Night and Protected Areas

    Science.gov (United States)

    Zhao, Yongheng

    2016-10-01

    Light at night (LAN) is now an established environmental problem, not only for astronomers but for the population at large. It has serious ecological effects that are wide ranging, and its environmental effects may be more serious than ever imagined. The ecological and environmental consequences are examined and emphasis is stressed on resolving the problem before it is too late.

  2. The impact of changing night vision goggle spectral response on night vision imaging system lighting compatibility

    Science.gov (United States)

    Task, Harry L.; Marasco, Peter L.

    2004-09-01

    The defining document outlining night-vision imaging system (NVIS) compatible lighting, MIL-L-85762A, was written in the mid 1980's, based on what was then the state of the art in night vision and image intensification. Since that time there have been changes in the photocathode sensitivity and the minus-blue coatings applied to the objective lenses. Specifically, many aviation night-vision goggles (NVGs) in the Air Force are equipped with so-called "leaky green" or Class C type objective lens coatings that provide a small amount of transmission around 545 nanometers so that the displays that use a P-43 phosphor can be seen through the NVGs. However, current NVIS compatibility requirements documents have not been updated to include these changes. Documents that followed and replaced MIL-L-85762A (ASC/ENFC-96-01 and MIL-STD-3009) addressed aspects of then current NVIS technology, but did little to change the actual content or NVIS radiance requirements set forth in the original MIL-L-85762A. This paper examines the impact of spectral response changes, introduced by changes in image tube parameters and objective lens minus-blue filters, on NVIS compatibility and NVIS radiance calculations. Possible impact on NVIS lighting requirements is also discussed. In addition, arguments are presented for revisiting NVIS radiometric unit conventions.

  3. Determining Light Pollution of the Global Sky: GLOBE at Night

    Science.gov (United States)

    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

  4. Dose-dependent responses of avian daily rhythms to artificial light at night

    NARCIS (Netherlands)

    de Jong, Maaike; Jeninga, Lizanne; Ouyang, Jenny Q; van Oers, Kees; Spoelstra, Kamiel; Visser, Marcel E

    2015-01-01

    Recent studies have shown that animals are affected by night-time light exposure. Light is a continuous variable, but our knowledge on how individuals react to different light intensities during the night is limited. We therefore determined the relationship between night light intensity and the

  5. DIMENSIONAL STABILITY AND WATER REPELLENT EFFICIENCY MEASUREMENT OF CHEMICALLY MODIFIED TROPICAL LIGHT HARDWOOD

    OpenAIRE

    Md. Saiful Islam; Sinin Hamdan; Mohamad Rusop; Md. Rezaur Rahman; Abu Saleh Ahmed; M. A. M. Mohd Idrus

    2012-01-01

    Chemical modification is an often-followed route to improve physical and mechanical properties of solid wood materials. In this study five kinds of tropical light hardwoods species, namely jelutong (Dyera costulata), terbulan (Endospermum diadenum), batai (Paraserianthes moluccana), rubberwood (Hevea brasiliensis), and pulai (Alstonia pneumatophora), were chemically modified with benzene diazonium salt to improve their dimensional stability and water repellent efficiency. The dimensional stab...

  6. Session 21.2 - Measurement of Light at Night

    Science.gov (United States)

    Wainscoat, Richard J.

    2016-10-01

    The introduction of the mercury vapor lamp for general lighting in the 1930s probably marked the beginning of significant light pollution. Lighting levels have increased slowly, year-to-year, with sky brightness levels increasing only slowly on timescales of a year; no measurement protocols or instruments existed to quantify this increase. However, on timescales of 10-20 years, or on generational timescales, the increases in night sky levels, particularly in urban areas, have been dramatic. Younger people speak with their parents or grandparents who remark how beautiful the sky used to be, and how many stars they could see when they when they were younger. Older people can themselves remember how many stars were visible in the sky when they were younger. Whole generations of children now grow up without ever seeing the Milky Way. Society has not had tools to easily measure sky brightness, and monitoring from space has only recently become available. A subtle increase of 10% sky brightness per year, for example, is not noticeable to the human eye on the time scale of a year, and has been tolerated by society. But such an increase compounds to an increase of a factor 2.6 in 10 years, 6.7 in 20 years, and a factor 45 in 40 years, corresponding to a dramatic increase in sky brightness, an almost complete loss in ability to see faint objects in the night sky, and rendering the sky unusable for most forms of astronomy. The most striking examples are the urban observatories found in many major cities that can no longer be used. Session 2 was primarily focused on measurement of light at night, with an emphasis on measurement of light pollution. It comprised of 6 papers that are summarized below. Over the last decade, our ability to measure light pollution has grown tremendously, and the instrumentation needed to produce reliable quantitative measurements has become much more affordable, and now includes consumer grade digital cameras and even smart phones. During this same

  7. Light-at-night-induced circadian disruption, cancer and aging.

    Science.gov (United States)

    Anisimov, Vladimir N; Vinogradova, Irina A; Panchenko, Andrei V; Popovich, Irina G; Zabezhinski, Mark A

    2012-12-01

    Light-at-night has become an increasing and essential part of the modern lifestyle and leads to a number of health problems, including excessive body mass index, cardiovascular diseases, diabetes, and cancer. The International Agency for Research on Cancer (IARC) Working Group concluded that "shift-work that involves circadian disruption is probably carcinogenic to humans" (Group 2A) [1]. According to the circadian disruption hypothesis, light-at-night might disrupt the endogenous circadian rhythm and specifically suppress nocturnal production of the pineal hormone melatonin and its secretion into the blood. We evaluated the effect of various light/dark regimens on the survival, life span, and spontaneous and chemical carcinogenesis in rodents. Exposure to constant illumination was followed by accelerated aging and enhanced spontaneous tumorigenesis in female CBA and transgenic HER-2/neu mice. In male and female rats maintained at various light/dark regimens (standard 12:12 light/dark [LD], the natural light [NL] of northwestern Russia, constant light [LL], and constant darkness [DD]) from the age of 25 days until natural death, it was found that exposure to NL and LL regimens accelerated age-related switch-off of the estrous function (in females), induced development of metabolic syndrome and spontaneous tumorigenesis, and shortened life span both in male and females rats compared to the standard LD regimen. Melatonin given in nocturnal drinking water prevented the adverse effect of the constant illumination (LL) and natural light (NL) regimens on the homeostasis, life span, and tumor development both in mice and rats. The exposure to the LL regimen accelerated colon carcinogenesis induced by 1,2-dimethylhydrazine (DMH) in rats, whereas the treatment with melatonin alleviated the effects of LL. The maintenance of rats at the DD regimen inhibited DMH-induced carcinogenesis. The LL regimen accelerated, whereas the DD regimen inhibited both mammary carcinogenesis

  8. Measuring urban sprawl in China by night time light images

    Science.gov (United States)

    Liu, Lu; Tang, Lin

    2017-01-01

    In the process of urbanization, a phenomenon called “urban sprawl” usually occurs. This phenomenon may exaggerated the negative effects of urbanization on environment, public and social health, energy efficiency, and maintenance of farmland. Therefore, the understanding of this phenomenon is urgently required for us to achieve sustainable development. This study proposed a group of night time lights (NTL) indicators of urban sprawl, which intend to use the distribution of lightness to quantify urban sprawl. These measures are proved to be efficient in describing urban sprawl. In addition, they are consistent and easy calculating, making comparison analysis easy to be done. These indicators are used to study urban sprawl in China during the year 2000 to 2010, the results show that in the last ten years, metropolitan areas in the northern part of China have undergone a more sprawl-like urban growth compared with other parts of China.

  9. Nanoimprint lithography for green water-repellent film derived from biomass with high-light transparency

    Science.gov (United States)

    Takei, Satoshi; Hanabata, Makoto

    2015-03-01

    Newly eco-friendly high light transparency film with plant-based materials was investigated to future development of liquid crystal displays and optical devices with water repellency as a chemical design concept of nanoimprint lithography. This procedure is proven to be suitable for material design and the process conditions of ultraviolet curing nanoimprint lithography for green water-repellent film derived from biomass with high-light transparency. The developed formulation of advanced nanoimprinted materials design derived from lactulose and psicose, and the development of suitable UV nanoimprint conditions produced high resolutions of the conical shaped moth-eye regularly-nanostructure less than approximately 200 nm diameter, and acceptable patterning dimensional accuracy by the replication of 100 times of UV nanoimprint lithography cycles. The newly plant-based materials and the process conditions are expected as one of the defect less nanoimprint lithographic technologies in next generation electronic devices.

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

    Science.gov (United States)

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

    2014-01-01

    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.

  11. The copepod Calanus spp. (Calanidae) is repelled by polarized light.

    Science.gov (United States)

    Lerner, Amit; Browman, Howard I

    2016-10-20

    Both attraction and repulsion from linearly polarized light have been observed in zooplankton. A dichotomous choice experiment, consisting of plankton light traps deployed in natural waters at a depth of 30 m that projected either polarized or unpolarized light of the same intensity, was used to test the hypothesis that the North Atlantic copepod, Calanus spp., is linearly polarotactic. In addition, the transparency of these copepods, as they might be seen by polarization insensitive vs. sensitive visual systems, was measured. Calanus spp. exhibited negative polarotaxis with a preference ratio of 1.9:1. Their transparency decreased from 80% to 20% to 30% in the unpolarized, partially polarized, and electric (e-) vector orientation domains respectively - that is, these copepods would appear opaque and conspicuous to a polarization-sensitive viewer looking at them under conditions rich in polarized light. Since the only difference between the two plankton traps was the polarization cue, we conclude that Calanus spp. are polarization sensitive and exhibit negative polarotaxis at low light intensities (albeit well within the sensitivity range reported for copepods). We hypothesize that Calanus spp. can use polarization vision to reduce their risk of predation by polarization-sensitive predators and suggest that this be tested in future experiments.

  12. The copepod Calanus spp. (Calanidae) is repelled by polarized light

    Science.gov (United States)

    Lerner, Amit; Browman, Howard I.

    2016-10-01

    Both attraction and repulsion from linearly polarized light have been observed in zooplankton. A dichotomous choice experiment, consisting of plankton light traps deployed in natural waters at a depth of 30 m that projected either polarized or unpolarized light of the same intensity, was used to test the hypothesis that the North Atlantic copepod, Calanus spp., is linearly polarotactic. In addition, the transparency of these copepods, as they might be seen by polarization insensitive vs. sensitive visual systems, was measured. Calanus spp. exhibited negative polarotaxis with a preference ratio of 1.9:1. Their transparency decreased from 80% to 20% to 30% in the unpolarized, partially polarized, and electric (e-) vector orientation domains respectively - that is, these copepods would appear opaque and conspicuous to a polarization-sensitive viewer looking at them under conditions rich in polarized light. Since the only difference between the two plankton traps was the polarization cue, we conclude that Calanus spp. are polarization sensitive and exhibit negative polarotaxis at low light intensities (albeit well within the sensitivity range reported for copepods). We hypothesize that Calanus spp. can use polarization vision to reduce their risk of predation by polarization-sensitive predators and suggest that this be tested in future experiments.

  13. Light at night as an environmental endocrine disruptor.

    Science.gov (United States)

    Russart, Kathryn L G; Nelson, Randy J

    2017-09-06

    Environmental endocrine disruptors (EEDs) are often consequences of human activity; however, the effects of EEDs are not limited to humans. A primary focus over the past ∼30years has been on chemical EEDs, but the repercussions of non-chemical EEDs, such as artificial light at night (LAN), are of increasing interest. The sensitivity of the circadian system to light and the influence of circadian organization on overall physiology and behavior make the system a target for disruption with widespread effects. Indeed, there is increasing evidence for a role of LAN in human health, including disruption of circadian regulation and melatonin signaling, metabolic dysregulation, cancer risk, and disruption of other hormonally-driven systems. These effects are not limited to humans; domesticated animals as well as wildlife are also exposed to LAN, and at risk for disrupted circadian rhythms. Here, we review data that support the role of LAN as an endocrine disruptor in humans to be considered in treatments and lifestyle suggestions. We also present the effects of LAN in other animals, and discuss the potential for ecosystem-wide effects of artificial LAN. This can inform decisions in agricultural practices and urban lighting decisions to avoid unintended outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. DIMENSIONAL STABILITY AND WATER REPELLENT EFFICIENCY MEASUREMENT OF CHEMICALLY MODIFIED TROPICAL LIGHT HARDWOOD

    Directory of Open Access Journals (Sweden)

    Md Saiful Islam,

    2012-01-01

    Full Text Available Chemical modification is an often-followed route to improve physical and mechanical properties of solid wood materials. In this study five kinds of tropical light hardwoods species, namely jelutong (Dyera costulata, terbulan (Endospermum diadenum, batai (Paraserianthes moluccana, rubberwood (Hevea brasiliensis, and pulai (Alstonia pneumatophora, were chemically modified with benzene diazonium salt to improve their dimensional stability and water repellent efficiency. The dimensional stability of treated samples in terms of volumetric swelling coefficient (S and anti-swelling-efficiency (ASE were found to improve with treatment. The water repellent efficiency (WRE values also seemed to improve considerably with treatment of wood samples. Furthermore, treated wood samples had lower water and moisture absorption compared to that of untreated ones.

  15. Multiple night-time light-emitting diode lighting strategies impact grassland invertebrate assemblages.

    Science.gov (United States)

    Davies, Thomas W; Bennie, Jonathan; Cruse, Dave; Blumgart, Dan; Inger, Richard; Gaston, Kevin J

    2017-07-01

    White light-emitting diodes (LEDs) are rapidly replacing conventional outdoor lighting technologies around the world. Despite rising concerns over their impact on the environment and human health, the flexibility of LEDs has been advocated as a means of mitigating the ecological impacts of globally widespread outdoor night-time lighting through spectral manipulation, dimming and switching lights off during periods of low demand. We conducted a three-year field experiment in which each of these lighting strategies was simulated in a previously artificial light naïve grassland ecosystem. White LEDs both increased the total abundance and changed the assemblage composition of adult spiders and beetles. Dimming LEDs by 50% or manipulating their spectra to reduce ecologically damaging wavelengths partially reduced the number of commoner species affected from seven to four. A combination of dimming by 50% and switching lights off between midnight and 04:00 am showed the most promise for reducing the ecological costs of LEDs, but the abundances of two otherwise common species were still affected. The environmental consequences of using alternative lighting technologies are increasingly well established. These results suggest that while management strategies using LEDs can be an effective means of reducing the number of taxa affected, averting the ecological impacts of night-time lighting may ultimately require avoiding its use altogether. © 2017 John Wiley & Sons Ltd.

  16. Candle light-style OLED: a plausibly human-friendly safe night light

    Science.gov (United States)

    Jou, Jwo-Huei; Chen, Po-Wei; Hsieh, Chun-Yu; Wang, Ching-Chiun; Chen, Chien-Chih; Tung, F.-C.; Chen, Szu-Hao; Wang, Yi-Shan

    2013-09-01

    Candles emit sensationally-warm light with a very-low color-temperature, comparatively most suitable for use at night. In response to the need for such a human-friendly night light, we demonstrate the employment of a high number of candle light complementary organic emitters to generate mimic candle light based on organic light emitting diode (OLED). One resultant candle light-style OLED shows a very-high color rendering index, with an efficacy at least 300 times that of candles or twice that of an incandescent bulb. The device can be fabricated, for example, by using four candle light complementary emitters, namely: red, yellow, green, and sky-blue phosphorescent dyes, vacuum-deposited into two emission layers, separated by a nano-layer of carrier modulation material to maximize both the desirable very-high color rendering index and energy efficiency, while keeping the blue emission very low and red emission high to obtain the desirable low color temperature. With different layer structures, the OLEDs can also show color tunable between that of candle light and dusk-hue. Importantly, a romantic sensation giving and supposedly physiologically-friendly candle light-style emission can hence be driven by electricity in lieu of the hydrocarbon-burning and greenhouse gas releasing candles that were invented 5,000 years ago.

  17. Contributions of artificial lighting sources on light pollution in Hong Kong measured through a night sky brightness monitoring network

    CERN Document Server

    Pun, Chun Shing Jason; Leung, Wai Yan; Wong, Chung Fai

    2014-01-01

    Light pollution is a form of environmental degradation in which excessive artificial outdoor lighting, such as street lamps, neon signs, and illuminated signboards, affects the natural environment and the ecosystem. Poorly designed outdoor lighting not only wastes energy, money, and valuable Earth resources, but also robs us of our beautiful night sky. Effects of light pollution on the night sky can be evaluated by the skyglow caused by these artificial lighting sources, through measurements of the night sky brightness (NSB). The Hong Kong Night Sky Brightness Monitoring Network (NSN) was established to monitor in detail the conditions of light pollution in Hong Kong. Monitoring stations were set up throughout the city covering a wide range of urban and rural settings to continuously measure the variations of the NSB. Over 4.6 million night sky measurements were collected from 18 distinct locations between May 2010 and March 2013. This huge dataset, over two thousand times larger than our previous survey, for...

  18. Night work, light exposure and melatonin on work days and days off

    DEFF Research Database (Denmark)

    Daugaard, Stine; Garde, Anne Helene; Bonde, Jens Peter Ellekilde

    2017-01-01

    We aimed to examine the effects of night work on salivary melatonin concentration during and subsequent to night work and the mediating role of light. We included 254 day workers and 87 night workers who were followed during 322 work days and 301 days off work. Each day was defined as the 24 hour...... period starting from the beginning of a night shift or from waking in the mornings with day work and days off. Light levels were recorded and synchronized with diary information (start and end of sleep and work). On average, participants provided four saliva samples per day, and these were analyzed....... For light exposure, we estimated the total, direct and indirect effects of night work on melatonin concentrations obtaining 95% confidence intervals through bootstrapping. On work days, night workers showed 15% lower salivary melatonin concentrations compared with day workers (-15.0%; 95% CI: -31.4%; 5...

  19. GLOBE at Night: a Worldwide Citizen-Science Program to Increase Awareness of Light Pollution by Measuring Night Sky Brightness

    Science.gov (United States)

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

    2011-12-01

    The emphasis in the international citizen-science, star-hunting campaign, GLOBE at Night, is in bringing awareness to the public on issues of light pollution. Light pollution threatens not only observatory sites and our "right to starlight", but can affect energy consumption, wildlife and health. GLOBE at Night has successfully reached a few 100,000 citizen-scientists. What has contributed to its success? Foundational resources are available to facilitate the public's participation in promoting dark skies awareness. The GLOBE at Night website explains clearly the simple-to-participate-in 5 step program and offers background information and interactive games on key concepts. To promote the campaign via popular social media, GLOBE at Night created Facebook and Twitter pages. The program has been expanded to include trainings of the general public, but especially educators in schools, museums and science centers, in unique ways. Education kits for dark skies awareness have been distributed at the training workshops. The kit includes material for a light shielding demonstration, a digital Sky Quality Meter and "Dark Skies Rangers" activities. The activities are on how unshielded light wastes energy, how light pollution affects wildlife and how one can participate in a citizen-science star-hunt like GLOBE at Night. To increase participation in the 2011 campaign, children and adults submitted their sky brightness measurements in real time with smart phones or tablets using the web application at www.globeatnight.org/webapp/. With smart phones and tablets, the location, date and time register automatically. For those without smart mobile devices, user-friendly tools on the GLOBE at Night report page were reconfigured to determine latitude and longitude more easily and accurately. As a proto-type for taking multiple measurements, people in Tucson found it easy to adopt a street and take measurements every mile for the length of the street. The grid of measurements

  20. Candlelight style organic light-emitting diode: a plausibly human-friendly safe night light

    Science.gov (United States)

    Jou, Jwo-Huei; Hsieh, Chun-Yu; Chen, Po-Wei; Kumar, Sudhir; Hong, James H.

    2014-01-01

    Candles emit sensationally warm light with a very low color temperature, comparatively most suitable for use at night. In response to the need for such a human-friendly night light, we demonstrate the employment of a high number of candlelight complementary organic emitters to generate and mimic candlelight based on organic light emitting diode (OLED). One resultant candlelight style OLED shows a very-high color rendering index (CRI), with an efficacy at least 300 times that of a candle or at least two times that of an incandescent bulb. The device can be fabricated, for example, by using four candlelight complementary emitters: red, yellow, green, and sky-blue phosphorescent dyes. These dyes, in the present system, can be vacuum deposited into two emission layers that are separated by a nanolayer of carrier modulation material that is used to maximize very high CRI and energy efficiency. A nano carrier modulation layer also played a significant role in maintaining the low blue emission and high-red emission, the low color temperature of device was obtained. Importantly, a romantic sensation giving and supposedly physiologically friendly candlelight style emission can hence be driven by electricity in lieu of hydrocarbon burning and greenhouse gas-releasing candles that were invented 5000 years ago.

  1. Decades of Urban Growth and Development on Deltas; Comparative Global Analysis of Night Lights and Population

    Science.gov (United States)

    Small, C.; Elvidge, C.; Yetman, G.; Baugh, K.; MacManus, K.

    2016-12-01

    It is well-known that coastal zones in general, and deltas in particular, are among the most densely populated environments on Earth. Decades of satellite imagery offer spatially explicit observations of the changing land use and development of deltas worldwide. Stable night lights provide globally consistent proxies for lighted development associated with a variety of human settlement types. Gridded census enumerations provide geospatial depictions of human population density associated with residential population distributions. Recent improvements in both night light imaging and census data resolution allow us to compare stable night light and residential population density with much greater spatial correspondence than previously possible. We use night light brightness from the Visible/Infrared Imaging Radiometer Suite (VIIRS) on the NASA/NOAA Suomi satellite and population density grids from the NASA SEDAC Gridded Population of the World v.4 (GPWv4) product to derive density/intensity transfer functions for a wide range of urban/rural gradients worldwide. These transfer functions provide the basis for spatial disaggregation of population using the higher resolution night light imagery in areas where census data lack the resolution for meaningful analysis of population and coastal hazard. Disaggregated population maps are combined with digital elevation models to estimate current population distributions with elevation and fluvial proximity for several of the world's most densely populated deltas. In addition, we use DMSP-OLS night light composites to map changes in lighted development on these deltas since 1992. Landsat imagery is then used to map the land cover changes associated with increases in night light brightness on these deltas. The result allows for spatially explicit comparisons of development patterns in different types of deltaic environments. We present a generalized methodology for mapping development and land cover with sufficient detail and

  2. From the Magic of Light to the Destruction of Night

    Science.gov (United States)

    Posch, Thomas

    2012-09-01

    Life on the Earth depends on the light from the Sun. Humans generally have a very positive attitude towards light. This paper discusses the 'magic of light' - i.e. our dependence on and even addiction to light - and how it gradually led to the destruction of natural darkness by means of excessive artificial illumination. Furthermore, we develop a theory of the aesthetic value of natural nightscapes, which we illustrate by masterpieces from the history of painting.

  3. Dim light at night disturbs the daily sleep-wake cycle in the rat

    NARCIS (Netherlands)

    Stenvers, Dirk Jan; van Dorp, Rick; Foppen, Ewout; Mendoza, Jorge; Opperhuizen, Anne-Loes; Fliers, Eric; Bisschop, Peter H; Meijer, Johanna H; Kalsbeek, A.; Deboer, Tom

    2016-01-01

    Exposure to light at night (LAN) is associated with insomnia in humans. Light provides the main input to the master clock in the hypothalamic suprachiasmatic nucleus (SCN) that coordinates the sleep-wake cycle. We aimed to develop a rodent model for the effects of LAN on sleep. Therefore, we exposed

  4. Night-sky brightness monitoring in Hong Kong: a city-wide light pollution assessment.

    Science.gov (United States)

    Pun, Chun Shing Jason; So, Chu Wing

    2012-04-01

    Results of the first comprehensive light pollution survey in Hong Kong are presented. The night-sky brightness was measured and monitored around the city using a portable light-sensing device called the Sky Quality Meter over a 15-month period beginning in March 2008. A total of 1,957 data sets were taken at 199 distinct locations, including urban and rural sites covering all 18 Administrative Districts of Hong Kong. The survey shows that the environmental light pollution problem in Hong Kong is severe-the urban night skies (sky brightness at 15.0 mag arcsec(- 2)) are on average ~ 100 times brighter than at the darkest rural sites (20.1 mag arcsec(- 2)), indicating that the high lighting densities in the densely populated residential and commercial areas lead to light pollution. In the worst polluted urban location studied, the night-sky at 13.2 mag arcsec(- 2) can be over 500 times brighter than the darkest sites in Hong Kong. The observed night-sky brightness is found to be affected by human factors such as land utilization and population density of the observation sites, together with meteorological and/or environmental factors. Moreover, earlier night skies (at 9:30 p.m. local time) are generally brighter than later time (at 11:30 p.m.), which can be attributed to some public and commercial lightings being turned off later at night. On the other hand, no concrete relationship between the observed sky brightness and air pollutant concentrations could be established with the limited survey sampling. Results from this survey will serve as an important database for the public to assess whether new rules and regulations are necessary to control the use of outdoor lightings in Hong Kong.

  5. Early Birds by Light at Night: Effects of Light Color and Intensity on Daily Activity Patterns in Blue Tits

    NARCIS (Netherlands)

    Jong, Maaike de; Caro, Samuel P.; Gienapp, Phillip; Spoelstra, Kamiel; Visser, Marcel E.

    2017-01-01

    Artificial light at night disturbs the daily rhythms of many organisms. To what extent this disturbance depends on the intensity and spectral composition of light remain obscure. Here, we measured daily activity patterns of captive blue tits (Cyanistes caeruleus) exposed to similar intensities of

  6. Preliminary evidence that both blue and red light can induce alertness at night

    Directory of Open Access Journals (Sweden)

    Plitnick Barbara

    2009-08-01

    Full Text Available Abstract Background A variety of studies have demonstrated that retinal light exposure can increase alertness at night. It is now well accepted that the circadian system is maximally sensitive to short-wavelength (blue light and is quite insensitive to long-wavelength (red light. Retinal exposures to blue light at night have been recently shown to impact alertness, implicating participation by the circadian system. The present experiment was conducted to look at the impact of both blue and red light at two different levels on nocturnal alertness. Visually effective but moderate levels of red light are ineffective for stimulating the circadian system. If it were shown that a moderate level of red light impacts alertness, it would have had to occur via a pathway other than through the circadian system. Methods Fourteen subjects participated in a within-subject two-night study, where each participant was exposed to four experimental lighting conditions. Each night each subject was presented a high (40 lx at the cornea and a low (10 lx at the cornea diffuse light exposure condition of the same spectrum (blue, λmax = 470 nm, or red, λmax = 630 nm. The presentation order of the light levels was counterbalanced across sessions for a given subject; light spectra were counterbalanced across subjects within sessions. Prior to each lighting condition, subjects remained in the dark ( Results Exposures to red and to blue light resulted in increased beta and reduced alpha power relative to preceding dark conditions. Exposures to high, but not low, levels of red and of blue light significantly increased heart rate relative to the dark condition. Performance and sleepiness ratings were not strongly affected by the lighting conditions. Only the higher level of blue light resulted in a reduction in melatonin levels relative to the other lighting conditions. Conclusion These results support previous findings that alertness may be mediated by the circadian system

  7. Globe at Night: From IYA2009 to the International Year of Light 2015 and Beyond

    Science.gov (United States)

    Walker, Constance Elaine; Pompea, Stephen M.; Sparks, Robert T.

    2015-08-01

    Citizen-science is a rewardingly inclusive way to bring awareness to the public on important issues like the disappearing starry night sky, its cause and solutions. Citizen-science can also provide meaningful, hands-on “science process” experiences for students. One program that does both is Globe at Night (www.globeatnight.org), an international campaign to raise public awareness of the impact of light pollution by having people measure night-sky brightness and submit observations via a “web app” on any smart device or computer. Additionally, 2 native mobile apps - Loss of the Night for iPhone & Android, and Dark Sky Meter for iPhone - support Globe at Night.Since 2006, more than 125,000 vetted measurements from 115 countries have been reported. For 2015 the campaign is offered as a 10-day observation window each month when the Moon is not up. To facilitate Globe at Night as an international project, the web app and other materials are in many languages. (See www.globeatnight.org/downloads.)Students and the general public can use the data to monitor levels of light pollution around the world, as well as understand light pollution’s effects on energy consumption, plants, wildlife, human health and our ability to enjoy a starry night sky. Projects have compared Globe at Night data with ground-truthing using meters for energy audits as well as with data on birds and bats, population density, satellite data and trends over time. Globe at Night tackles grand challenges and everyday problems. It provides resources for formal and informal educators to engage learners of all ages. It has 9 years of experience in best practices for data management, design, collection, visualization, interpretation, etc. It has externally evaluated its program, workshops, lesson plans and accompanying kit to explore reasons for participation, skills developed, impact of experiences and perceived outcomes. Three recent papers (Birriel et al. 2014; Kyba et al. 2013; 2015) verify the

  8. Short-wavelength attenuated polychromatic white light during work at night : Limited melatonin suppression without substantial decline of alertness

    NARCIS (Netherlands)

    van de Werken, Maan; Giménez, Marina C; de Vries, Bonnie; Beersma, Domien G M; Gordijn, Marijke C M

    Exposure to light at night increases alertness, but light at night (especially short-wavelength light) also disrupts nocturnal physiology. Such disruption is thought to underlie medical problems for which shiftworkers have increased risk. In 33 male subjects we investigated whether short-wavelength

  9. DEET (N,N-diethyl-meta-toluamide)/PMD (para-menthane-3,8-diol) repellent-treated mesh increases Culicoides catches in light traps.

    Science.gov (United States)

    Murchie, A K; Clawson, S; Rea, I; Forsythe, I W N; Gordon, A W; Jess, S

    2016-09-01

    Biting midges (Culicoides spp.) are vectors of bluetongue and Schmallenberg viruses. Treatment of mesh barriers is a common method for preventing insect-vectored diseases and has been proposed as a means of limiting Culicoides ingression into buildings or livestock transporters. Assessments using animals are costly, logistically difficult and subject to ethical approval. Therefore, initial screening of test repellents/insecticides was made by applying treatments to mesh (2 mm) cages surrounding Onderstepoort light traps. Five commercial treatments were applied to cages as per manufacturers' application rates: control (water), bendiocarb, DEET/p-menthane-3,8-diol (PMD) repellent, Flygo (a terpenoid based repellent) and lambda-cyhalothrin. The experimental design was a 5 × 5 Latin square, replicated in time and repeated twice. Incongruously, the traps surrounded by DEET/PMD repellent-treated mesh caught three to four times more Obsoletus group Culicoides (the commonest midge group) than the other treatments. A proposed hypothesis is that Obsoletus group Culicoides are showing a dose response to DEET/PMD, being attracted at low concentrations and repelled at higher concentrations but that the strong light attraction from the Onderstepoort trap was sufficient to overcome close-range repellence. This study does not imply that DEET/PMD is an ineffective repellent for Culicoides midges in the presence of an animal but rather that caution should be applied to the interpretation of light trap bioassays.

  10. Night-sky brightness monitoring in Hong Kong - a city-wide light pollution assessment

    CERN Document Server

    Pun, Chun Shing Jason

    2011-01-01

    Results of the first comprehensive light pollution survey in Hong Kong are presented. The night-sky brightness was measured and monitored around the city using a portable light sensing device called the Sky Quality Meter over a 15-month period beginning in March 2008. A total of 1,957 data sets were taken at 199 distinct locations, including urban and rural sites covering all 18 Administrative Districts of Hong Kong. The survey shows that the environmental light pollution problem in Hong Kong is severe - the urban night-skies (sky brightness at 15.0 mag per arcsec square) are on average ~100 times brighter than at the darkest rural sites (20.1 mag per arcsec square), indicating that the high lighting densities in the densely populated residential and commercial areas lead to light pollution. In the worst polluted urban location studied, the night-sky at 13.2 mag per arcsec square can be over 500 times brighter than the darkest sites in Hong Kong. The observed night-sky brightness is found to be affected by hu...

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

    Science.gov (United States)

    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).

  12. Effect of Light at Night on oxidative stress markers in Golden spiny mice (Acomys russatus) liver.

    Science.gov (United States)

    Ashkenazi, Lilach; Haim, Abraham

    2013-07-01

    Light at Night (LAN) suppresses melatonin (MLT) production, and effects metabolism, hormone secretion, gene expression and enzyme activity. Changes in antioxidant enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD), can be used as an indication for oxidative stress level. We assayed activity and expression of these enzymes in the liver of Acomys russatus exposed to LAN and treated with MLT. Short day (SD)-acclimated A. russatus, was exposed to 30min of LAN for two, seven or 21 nights. MLT impact was assessed simultaneously with two and seven nights of LAN exposure. GPx and SOD activities were measured. Gpx1 expression was evaluated by RT-PCR. There was a significant increase in GPx activity following LAN exposure for all acclimation durations, GPx activity was elevated after two nights of LAN and MLT treatment, Gpx1 expression was elevated by MLT after seven nights of LAN. SOD activity increased after two nights of LAN in MLT-treated A. russatus, GPx activity increased with the duration of LAN acclimation, indicating changes in liver redox status. Our results suggest that LAN is a stressor that influences oxidative stress. As in the other studies, MLT increases antioxidant activities, presumably attenuating stress response, in order to restore homeostasis.

  13. Urban artificial light emission function determined experimentally using night sky images

    Science.gov (United States)

    Solano Lamphar, Héctor Antonio; Kocifaj, Miroslav

    2016-09-01

    To date, diverse approximations have been developed to interpret the radiance of a night sky due to light emissions from ground-based light sources. The radiant intensity distribution as a function of zenith angle is one of the most unknown properties because of the collective effects of all artificial, private and public lights. The emission function (EF) is, however, a key property in modeling the skyglow under arbitrary conditions, and thus it is equally required by modelers, light pollution researchers, and also experimentalists who are using specialized devices to study the diffuse light of a night sky. In this paper, we present the second generation of a dedicated measuring system intended for routine monitoring of a night sky in any region. The experimental technology we have developed is used to interpret clear sky radiance data recorded at a set of discrete distances from a town (or city) with the aim to infer the fraction of upwardly emitted light (F), that is a parameter scaling the bulk EF. The retrieval of the direct upward emissions has been improved by introducing a weighting factor that is used to eliminate imperfections of experimental data and thus to make the computation of F more stable when processing the radiance data taken at two adjacent measuring points. The field experiments made in three Mexican cities are analyzed and the differences found are discussed.

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

    Science.gov (United States)

    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 (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.

  15. Exposure to dim artificial light at night increases REM sleep and awakenings in humans.

    Science.gov (United States)

    Cho, Chul-Hyun; Lee, Heon-Jeong; Yoon, Ho-Kyoung; Kang, Seung-Gul; Bok, Ki-Nam; Jung, Ki-Young; Kim, Leen; Lee, Eun-Il

    2016-01-01

    Exposure to artificial light at night (ALAN) has become increasing common, especially in developed countries. We investigated the effect of dALAN exposure during sleep in healthy young male subjects. A total of 30 healthy young male volunteers from 21 to 29 years old were recruited for the study. They were randomly divided into two groups depending on light intensity (Group A: 5 lux and Group B: 10 lux). After a quality control process, 23 healthy subjects were included in the study (Group A: 11 subjects, Group B: 12 subjects). Subjects underwent an NPSG session with no light (Night 1) followed by an NPSG session randomly assigned to two different dim light conditions (5 or 10 lux, dom λ: 501.4 nm) for a whole night (Night 2). We found significant sleep structural differences between Nights 1 and 2, but no difference between Groups A and B. Exposure to dALAN during sleep was significantly associated with increased wake time after sleep onset (WASO; F = 7.273, p = 0.014), increased Stage N1 (F = 4.524, p = 0.045), decreased Stage N2 (F = 9.49, p = 0.006), increased Stage R (F = 6.698, p = 0.017) and non-significantly decreased REM density (F = 4.102, p = 0.056). We found that dALAN during sleep affects sleep structure. Exposure to dALAN during sleep increases the frequency of arousals, amount of shallow sleep and amount of REM sleep. This suggests adverse effects of dALAN during sleep on sleep quality and suggests the need to avoid exposure to dALAN during sleep.

  16. Observation and interpretation of fast sub-visual light pulses from the night sky

    Science.gov (United States)

    Nemzek, R. J.; Winckler, J. R.

    1989-01-01

    Fast large-aperture photometers directed at the zenith on clear nights near Minneapolis have recorded many light pulses in the msec time range, but aside from man-made events these were almost entirely due to Rayleigh-scattered distant lightning, with a residual very low rate (less than 0.1/hr) of unidentified pulses. It is argued that 1-msec light pulses seen in several previous experiments may also be mostly Rayleigh-scattered lightning, rather than fluorescent light due to electron precipitation from lightning-induced whistlers as previously proposed.

  17. Parental Exposure to Dim Light at Night Prior to Mating Alters Offspring Adaptive Immunity

    Science.gov (United States)

    Cissé, Yasmine M.; Russart, Kathryn L.G.; Nelson, Randy J.

    2017-01-01

    Exposure to dim light at night (dLAN) disrupts natural light/dark cycles and impairs endogenous circadian rhythms necessary to maintain optimal biological function, including the endocrine and immune systems. We have previously demonstrated that white dLAN compromises innate and cell mediated immune responses in adult Siberian hamsters (Phodopus sungorus). We hypothesized that dLAN has transgenerational influences on immune function. Adult male and female Siberian hamsters were exposed to either dark nights (DARK) or dLAN (~5 lux) for 9 weeks, then paired in full factorial design, mated, and thereafter housed under dark nights. Offspring were gestated and reared in dark nights, then tested as adults for cell-mediated and humoral immunity. Maternal exposure to dLAN dampened delayed type hypersensitivity (DTH) responses in male offspring. Maternal and paternal exposure to dLAN reduced DTH responses in female offspring. IgG antibodies to a novel antigen were elevated in offspring of dams exposed to dLAN. Paternal exposure to dLAN decreased splenic endocrine receptor expression and global methylation in a parental sex-specific manner. Together, these data suggest that exposure to dLAN has transgenerational effects on endocrine-immune function that may be mediated by global alterations in the epigenetic landscape of immune tissues. PMID:28361901

  18. Artificial light alters natural regimes of night-time sky brightness

    Science.gov (United States)

    Davies, Thomas W.; Bennie, Jonathan; Inger, Richard; Gaston, Kevin J.

    2013-04-01

    Artificial light is globally one of the most widely distributed forms of anthropogenic pollution. However, while both the nature and ecological effects of direct artificial lighting are increasingly well documented, those of artificial sky glow have received little attention. We investigated how city lights alter natural regimes of lunar sky brightness using a novel ten month time series of measurements recorded across a gradient of increasing light pollution. In the city, artificial lights increased sky brightness to levels six times above those recorded in rural locations, nine and twenty kilometers away. Artificial lighting masked natural monthly and seasonal regimes of lunar sky brightness in the city, and increased the number and annual regime of full moon equivalent hours available to organisms during the night. The changes have potentially profound ecological consequences.

  19. Circadian disruption induced by light-at-night accelerates aging and promotes tumorigenesis in rats

    Science.gov (United States)

    Vinogradova, Irina A.; Anisimov, Vladimir N.; Bukalev, Andrey V.; Semenchenko, Anna V.; Zabezhinski, Mark A.

    2009-01-01

    We evaluated the effect of various light/dark regimens on the survival, life span and tumorigenesis in rats. Two hundred eight male and 203 females LIO rats were subdivided into 4 groups and kept at various light/dark regimens: standard 12:12 light/dark (LD); natural lighting of the North-West of Russia (NL); constant light (LL), and constant darkness (DD) since the age of 25 days until natural death. We found that exposure to NL and LL regimens accelerated development of metabolic syndrome and spontaneous tumorigenesis, shortened life span both in male and females rats as compared to the standard LD regimen. We conclude that circadian disruption induced by light-at-night accelerates aging and promotes tumorigenesis in rats. This observation supports the conclusion of the International Agency Research on Cancer that shift-work that involves circadian disruption is probably carcinogenic to humans. PMID:20157558

  20. SkyGlowNet: Multi-Disciplinary Independent Student Research in Environmental Light at Night Monitoring

    Science.gov (United States)

    Craine, B. L.; Craine, E. R.; Culver, R. B.; DeBenedetti, J. C.; Flurchick, K. M.

    2014-07-01

    SkyGlowNet uses Internet-enabled sky brightness meters (iSBM) to monitor sky brightness over school sites. The data are used professionally and in STEM outreach to study natural and artificial sources of sky brightness, light pollution, energy efficiency, and environmental and health impacts of artificial night lighting. The iSBM units are owned by participating institutions and managed by faculty or students via proprietary Internet links. Student data are embargoed for two semesters to allow students to analyze data and publish results, then they are moved to a common area where students from different institutions can collaborate. The iSBM units can be set to operate automatically each night. Their data include time, sky brightness, weather conditions, and other related parameters. The data stream can be viewed and processed online or downloaded for study. SkyGlowNet is a unique, multi-disciplinary, real science program aiding research for science and non-science students.

  1. Evaluation of blue light exposure to beta brainwaves on simulated night driving

    Science.gov (United States)

    Purawijaya, Dandri Aly; Fitri, Lulu Lusianti; Suprijanto

    2015-09-01

    Numbers of night driving accident in Indonesia since 2010 are exponentially rising each year with total of loss more than 50 billion rupiah. One of the causes that contribute to night driving accident is drowsiness. Drowsiness is affected by circadian rhythm resulted from the difference of blue light quality and quantity between night and day. Blue light may effect on human physiology through non-visual pathway by suppressing melatonin hormone suppression that influence drowsiness. Meanwhile, the production of hormones and other activities in brain generate bioelectrical activity such as brainwaves and can be recorded using Electroencephalograph (EEG). Therefore, this research objective is to evaluate the effect of blue light exposure to beta brainwave emergence during night driving simulation to a driver. This research was conducted to 4 male subjects who are able to drive and have a legitimate car driving license. The driving simulator was done using SCANIA Truck Driving Simulator on freeform driving mode in dark environment. Subjects drove for total 32 minutes. The data collections were taken in 2 days with 16 minutes for each day. The 16 minutes were divided again into 8 minutes adaptation in dark and 8 minutes for driving either in blue light exposure or in total darkness. While driving the simulation, subjects' brainwaves were recorded using EEG EMOTIV 14 Channels, exposed by LED monochromatic blue light with 160 Lux from source and angle 45o and sat 1 m in front of the screen. Channels used on this research were for visual (O1; O2), cognition (F3; F4; P7; P8), and motor (FC5; FC6). EEG brainwave result was filtered with EEGLab to obtain beta waves at 13 - 30 Hz frequencies. Results showed that beta waves response to blue light varied for each subject. Blue light exposure either increased or decreased beta waves in 2 minutes pattern and maintaining beta waves on cognition and motor area in 3 out of 4 subjects. Meanwhile, blue light exposure did not maintain

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

    National Research Council Canada - National Science Library

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

    2014-01-01

    ... 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...

  3. Light at night alters daily patterns of cortisol and clock proteins in female Siberian hamsters.

    Science.gov (United States)

    Bedrosian, T A; Galan, A; Vaughn, C A; Weil, Z M; Nelson, R J

    2013-06-01

    Humans and other organisms have adapted to a 24-h solar cycle in response to life on Earth. The rotation of the planet on its axis and its revolution around the sun cause predictable daily and seasonal patterns in day length. To successfully anticipate and adapt to these patterns in the environment, a variety of biological processes oscillate with a daily rhythm of approximately 24 h in length. These rhythms arise from hierarchally-coupled cellular clocks generated by positive and negative transcription factors of core circadian clock gene expression. From these endogenous cellular clocks, overt rhythms in activity and patterns in hormone secretion and other homeostatic processes emerge. These circadian rhythms in physiology and behaviour can be organised by a variety of cues, although they are most potently entrained by light. In recent history, there has been a major change from naturally-occurring light cycles set by the sun, to artificial and sometimes erratic light cycles determined by the use of electric lighting. Virtually every individual living in an industrialised country experiences light at night (LAN) but, despite its prevalence, the biological effects of such unnatural lighting have not been fully considered. Using female Siberian hamsters (Phodopus sungorus), we investigated the effects of chronic nightly exposure to dim light on daily rhythms in locomotor activity, serum cortisol concentrations and brain expression of circadian clock proteins (i.e. PER1, PER2, BMAL1). Although locomotor activity remained entrained to the light cycle, the diurnal fluctuation of cortisol concentrations was blunted and the expression patterns of clock proteins in the suprachiasmatic nucleus and hippocampus were altered. These results demonstrate that chronic exposure to dim LAN can dramatically affect fundamental cellular function and emergent physiology.

  4. DEET mosquito repellent sold through social marketing provides personal protection against malaria in an area of all-night mosquito biting and partial coverage of insecticide-treated nets: a case-control study of effectiveness.

    Science.gov (United States)

    Rowland, Mark; Freeman, Tim; Downey, Gerald; Hadi, Abdul; Saeed, Mohammed

    2004-03-01

    DEET (diethyl-3-methylbenzamide), the widely used mosquito repellent, has the potential to prevent malarial infection but hitherto there has been no study demonstrating this possibility during normal everyday use. Mosbar, a repellent soap containing DEET, was promoted through social marketing in villages in eastern Afghanistan. This was followed up with a case-control study of effectiveness against malarial infection conducted through local clinics. Mosbar was purchased by 43% of households. Reported use of insecticide-treated nets (ITNs) was 65% among the control group. There was a strong association between Mosbar use and ITN use, as 81% of Mosbar users also possessed ITN. The use of Mosbar was associated with a 45% reduction in the odds of malaria (95% CI: -11% to 72%, P=0.08) after adjusting for ITN and other unmatched factors. Ownership of ITNs was associated with a 46% reduction in the odds of malaria (95% CI: 12% to 67%, P=0.013) after adjusting for Mosbar and other unmatched factors. The greatest reduction in the odds of malaria was associated with combined use of Mosbar and ITN (69% reduction, 95% CI: 28% to 87%, P=0.007). The association between recalled use of Mosbar 10 days ago (nearer the time of infection) and reduction in malarial infections (adjusted odds ratio 0.08, 95% CI: 0.01-0.61, P=0.001) was significantly stronger than that shown by current use of Mosbar. Most purchasers of Mosbar were satisfied with the product (74%), although a minority said they preferred to use only ITN (8%). The local mosquito vectors, Anopheles stephensi and A. nigerrimus, started biting shortly after dusk and continued biting until early morning. It was shown that Mosbar prevented biting throughout this period. In regions where mosquito vectors bite during evening and night, repellents could have a useful supplementary role to ITN and their use should be more widely encouraged.

  5. Prolonging the hydration and active metabolism from light periods into nights substantially enhances lichen growth.

    Science.gov (United States)

    Bidussi, Massimo; Gauslaa, Yngvar; Solhaug, Knut Asbjørn

    2013-05-01

    This study investigates how hydration during light and dark periods influences growth in two epiphytic old forest lichens, the green algal Lobaria pulmonaria and the cyanobacterial L. scrobiculata. The lichens were cultivated in growth chambers for 14 days (200 μmol m(-1) s(-2); 12 h photoperiod) at four temperature regimes (25/20 °C, 21/16 °C, 13/8 °C, and 6/1 °C; day/night temperatures) and two hydration regimes (12 h day-time hydration; 12 h day-time + 12 h night-time hydration). Growth was highly dynamic, showing that short-term growth experiments in growth cabinets have a high, but largely unexplored potential in functional lichen studies. The highest measured growth rates were not far from the maximal dry matter gain estimated from published net photosynthetic CO2 uptake data. For the entire data set, photobiont type, temperature, hydration regime and specific thallus mass accounted for 46.6 % of the variation in relative growth rate (RGR). Both species showed substantially higher relative growth rates based on both biomass (RGR) and thallus area (RTAGR) when they were hydrated day and night compared to hydration in light only. Chronic photoinhibition was substantial in thalli hydrated only during the day time and kept at the highest and lowest temperature regimes, resulting in exponential increases in RGR with increasing maximal PSII efficiency (F v/F m) in both species. However, the depression in F v/F m was stronger for the cyanolichen than for the cephalolichen at extreme temperatures. The growth-stimulating effect of night-time hydration suggests that nocturnal metabolic activity improves recovery of photoinhibition and/or enhances the conversion rate of photosynthates into thallus extension.

  6. A single night light exposure acutely alters hormonal and metabolic responses in healthy participants

    Directory of Open Access Journals (Sweden)

    Mohammed S Albreiki

    2017-01-01

    Full Text Available Many animal studies have reported an association between melatonin suppression and the disturbance of metabolic responses; yet, few human studies have investigated bright light effects on metabolic and hormonal responses at night. This study investigated the impact of light on plasma hormones and metabolites prior to, and after, an evening meal in healthy participants. Seventeen healthy participants, 8 females (22.2 ± 2.59 years, mean ± s.d. and 9 males (22.8 ± 3.5 years were randomised to a two-way cross-over design protocol; dim light (DL (500 lux sessions, separated by at least seven days. Saliva and plasma samples were collected prior to and after a standard evening meal at specific intervals. Plasma non-esterified fatty acid (NEFA levels were significantly higher pre-meal in DL compared to BL (P < 0.01. Plasma glucose and insulin levels were significantly greater post-meal in the BL compared to DL session (P = 0.02, P = 0.001, respectively. Salivary melatonin levels were significantly higher in the DL compared to those in BL session (P = 0.005. BL at night was associated with significant increases in plasma glucose and insulin suggestive of glucose intolerance and insulin insensitivity. Raised pre-prandial NEFA levels may be due to changes in insulin sensitivity or the presence of melatonin and/or light at night. Plasma triglyceride (TAG levels were the same in both sessions. These results may explain some of the health issues reported in shift workers; however, further studies are needed to elucidate the cause of these metabolic changes.

  7. RESEARCH OF NIGHT LIGHT EFFECTS ON COLORIMETRIC CHARACTERISTICS OF IMAGE PERCEIVED BY THE PILOT IN AN AIRCRAFT COCKPIT

    OpenAIRE

    I. O. Zharinov; O. O. Zharinov

    2015-01-01

    Subject of Research. The influence of radiation spectra from the source of artificial night light on colorimetric characteristics of image perceived by the pilot in the aircraft cockpit has been studied. The image is displayed on the LCD screen of multifunctional color indication equipment unit. Night illumination of the cockpit is performed with the use of artificial lamps of red, green, blue and, rarely, white light. Method. Any given color to be displayed on the screen is perceived by an o...

  8. Artificial light at night causes diapause inhibition and sex-specific life history changes in a moth

    NARCIS (Netherlands)

    Geffen, van K.G.; Grunsven, van R.H.A.; Ruijven, van J.; Berendse, F.; Veenendaal, E.M.

    2014-01-01

    Rapidly increasing levels of light pollution subject nocturnal organisms to major alterations of their habitat, the ecological consequences of which are largely unknown. Moths are well-known to be attracted to light at night, but effects of light on other aspects of moth ecology, such as larval deve

  9. Study on real-time registration in dual spectrum low level light night vision technique

    Science.gov (United States)

    Bai, Lian-fa; Zhang, Yi; Zhang, Chuang; Chen, Qian; Gu, Guo-hua

    2009-07-01

    In low level light (LLL) color night vision technology, dual spectrum images with respective special information were acquired, and target identification probability would be effectively improved through dual spectrum image fusion. Image registration is one of the key technologies during this process. Current dual spectrum image registration methods mainly include dual imaging channel common optical axis scheme and image characteristic pixel searching scheme. In dual imaging channel common optical axis scheme, additional prismatic optical components should be used, and large amount of radiative energy was wasted. In image characteristic pixel searching scheme, complicated arithmetic made it difficult for its real time realization. In this paper, dual channel dual spectrum LLL color night vision system structure feature and dual spectrum image characteristics was studied, dual spectrum image gray scale symbiotic matrix 2-dimensional histogram was analysed, and a real time image registration method including electronic digital shifting, pixel extension and extraction was put forward. By the analysis of spatial gray-scale relativity of fusion image, registration precision is quantitatively expressed. Emulation experiments indicate that this arithmetic is fast and exact for our dual channel dual spectrum image registration. This method was realized on dual spectrum LLL color night vision experimental apparatus based on Texas Instruments digital video processing device DM642.

  10. Artificial light at night alters delayed-type hypersensitivity reaction in response to acute stress in Siberian hamsters.

    Science.gov (United States)

    Bedrosian, Tracy A; Aubrecht, Taryn G; Kaugars, Katherine E; Weil, Zachary M; Nelson, Randy J

    2013-11-01

    Several physiological and behavioral processes rely on precisely timed light information derived from the natural solar cycle. Using this information, traits have adapted to allow individuals within specific niches to optimize survival and reproduction, but urbanization by humans has significantly altered natural habitats. Nighttime light exposure alters immune function in several species, which could lead to decreased fitness or survival, particularly in the face of an environmental challenge. We exposed male Siberian hamsters (Phodopus sungorus) to five lux of light at night for four weeks, and then administered six hours of acute restraint stress. Delayed-type hypersensitivity (DTH) response was assessed immediately following stress. Acute restraint increased the DTH reaction in dark nights, but exposure to nighttime light prevented this response. Exposure to light at night prolonged the DTH response in non-stressed control hamsters. These results suggest that light pollution may significantly alter physiological responses in Siberian hamsters, particularly in response to a salient environmental challenge such as stress.

  11. Effects of Red Light Night Break Treatment on Growth and Flowering of Tomato Plants

    OpenAIRE

    Kai eCao; Lirong eCui; Lin eYe; Xiaoting eZhou; Encai eBao; Hailiang eZhao; Zhirong eZou

    2016-01-01

    Compact and healthy young plants increase crop production and improve vegetable quality. Adverse climatic conditions and shading can cause young plants to become elongated and spindly. We investigated the effects of night break (NB) treatments on tomato plants using red light (RL) with an intensity of 20 µmol•m2•s-1. Tomato plants were subjected to NB treatments with different frequencies ranging from every 1, 2, 3, and 4 h, and plant growth, flowering, and yield were monitored. The results s...

  12. Nonvisual responses to light exposure in the human brain during the circadian night.

    Science.gov (United States)

    Perrin, Fabien; Peigneux, Philippe; Fuchs, Sonia; Verhaeghe, Stéphane; Laureys, Steven; Middleton, Benita; Degueldre, Christian; Del Fiore, Guy; Vandewalle, Gilles; Balteau, Evelyne; Poirrier, Robert; Moreau, Vincent; Luxen, André; Maquet, Pierre; Dijk, Derk-Jan

    2004-10-26

    The brain processes light information to visually represent the environment but also to detect changes in ambient light level. The latter information induces non-image-forming responses and exerts powerful effects on physiology such as synchronization of the circadian clock and suppression of melatonin. In rodents, irradiance information is transduced from a discrete subset of photosensitive retinal ganglion cells via the retinohypothalamic tract to various hypothalamic and brainstem regulatory structures including the hypothalamic suprachiasmatic nuclei, the master circadian pacemaker. In humans, light also acutely modulates alertness, but the cerebral correlates of this effect are unknown. We assessed regional cerebral blood flow in 13 subjects attending to auditory and visual stimuli in near darkness following light exposures (>8000 lux) of different durations (0.5, 17, 16.5, and 0 min) during the biological night. The bright broadband polychromatic light suppressed melatonin and enhanced alertness. Functional imaging revealed that a large-scale occipito-parietal attention network, including the right intraparietal sulcus, was more active in proportion to the duration of light exposures preceding the scans. Activity in the hypothalamus decreased in proportion to previous illumination. These findings have important implications for understanding the effects of light on human behavior.

  13. Can Avoiding Light at Night Reduce the Risk of Breast Cancer?

    Science.gov (United States)

    Keshet-Sitton, Atalya; Or-Chen, Keren; Yitzhak, Sara; Tzabary, Ilana; Haim, Abraham

    2016-06-01

    Excessive exposure to artificial light at night (ALAN) suppresses nocturnal melatonin (MLT) production in the pineal gland and is, therefore, associated with an increased risk of breast cancer (BC). We examined indoor and outdoor light habits of 278 women, BC patients (n = 93), and controls (n = 185; 2010-2014). Cases and controls were age and residential area matched. Data regarding behavior in the sleeping habitat in a 5-year period, 10 to 15 years prior to disease diagnosis, were collected using a questionnaire. Sleep quality, bedtime, sleep duration, TV watching habits, presleeping reading habits, subjective illumination intensity, and type of illumination were collected. Binary logistic regression models were used to calculate odds ratios with 95% confidence intervals (ORs with 95% CIs) for BC patients in relation to those habits. OR results revealed that women who had slept longer (controls), 10 to 15 years before the time of the study, in a period of 5 years, had a significant (OR = 0.74; 95% CI = 0.57-0.97; P light (reading lamp) illumination and women who had slept with closed shutters reduced their BC risk: OR = 0.81, 95% CI = 0.67-0.97, P light exposure will diminish BC risk and incidence. This hypothesis needs to be tested directly using available testing strategies and technologies that continuously measure an individual's light exposure, its timing, and sleep length longitudinally and feed this information back to the individual, so that BC risk can be distinguished prospectively.

  14. Dim light at night disturbs the daily sleep-wake cycle in the rat

    Science.gov (United States)

    Jan Stenvers, Dirk; van Dorp, Rick; Foppen, Ewout; Mendoza, Jorge; Opperhuizen, Anne-Loes; Fliers, Eric; Bisschop, Peter H.; Meijer, Johanna H.; Kalsbeek, Andries; Deboer, Tom

    2016-01-01

    Exposure to light at night (LAN) is associated with insomnia in humans. Light provides the main input to the master clock in the hypothalamic suprachiasmatic nucleus (SCN) that coordinates the sleep-wake cycle. We aimed to develop a rodent model for the effects of LAN on sleep. Therefore, we exposed male Wistar rats to either a 12 h light (150–200lux):12 h dark (LD) schedule or a 12 h light (150–200 lux):12 h dim white light (5 lux) (LDim) schedule. LDim acutely decreased the amplitude of daily rhythms of REM and NREM sleep, with a further decrease over the following days. LDim diminished the rhythms of 1) the circadian 16–19 Hz frequency domain within the NREM sleep EEG, and 2) SCN clock gene expression. LDim also induced internal desynchronization in locomotor activity by introducing a free running rhythm with a period of ~25 h next to the entrained 24 h rhythm. LDim did not affect body weight or glucose tolerance. In conclusion, we introduce the first rodent model for disturbed circadian control of sleep due to LAN. We show that internal desynchronization is possible in a 24 h L:D cycle which suggests that a similar desynchronization may explain the association between LAN and human insomnia. PMID:27762290

  15. Characterization of Light at Night Data from Select SkyGlowNet Nodes

    Science.gov (United States)

    Flurchick, K. M.; Deal, S.; Foster, C.

    2013-05-01

    Internet-enabled sky brightness meters (iSBMs) that continuously record and log sky brightness at the zenith have been installed at the prototype nodes of a network called SkyGlowNet. Also logged are time and weather information. These data are polled at a user-defined frequency, typically about every 45 seconds. Although the SkyGlowNetdata are used for various professional scientific studies, they are also useful for independent student research projects. In this case, the data are uploaded to the SkyGlowNetwebsite, initially to a proprietary area where the data for each institution are embargoed for one or two semesters as students conduct research projects with their data. When released from embargo, the data are moved to another area where they can be accessed by all SkyGlowNet participants. In this paper, we describe a student project in which the data collected at two SkyGlowNet sites are characterized. The data streams are parsed into homogenous segments and statistical tools are employed to describe variations observed in the data values. We demonstrate how to differentiate between natural phenomena and the effects of artificial lighting on the brightness of the night sky. In our poster we show how these effects compare between sites as separate as Arizona and North Carolina. We also have experimented with the development of statistical metrics that are used to help categorize sky brightness on select nights, and can nearly automatically provide a characterization of the quality of the night sky for astronomical purposes.

  16. Dim light at night disrupts the short-day response in Siberian hamsters.

    Science.gov (United States)

    Ikeno, Tomoko; Weil, Zachary M; Nelson, Randy J

    2014-02-01

    Photoperiodic regulation of physiology, morphology, and behavior is crucial for many animals to survive seasonally variable conditions unfavorable for reproduction and survival. The photoperiodic response in mammals is mediated by nocturnal secretion of melatonin under the control of a circadian clock. However, artificial light at night caused by recent urbanization may disrupt the circadian clock, as well as the photoperiodic response by blunting melatonin secretion. Here we examined the effect of dim light at night (dLAN) (5lux of light during the dark phase) on locomotor activity rhythms and short-day regulation of reproduction, body mass, pelage properties, and immune responses of male Siberian hamsters. Short-day animals reduced gonadal and body mass, decreased spermatid nuclei and sperm numbers, molted to a whiter pelage, and increased pelage density compared to long-day animals. However, animals that experienced short days with dLAN did not show these short-day responses. Moreover, short-day specific immune responses were altered in dLAN conditions. The nocturnal activity pattern was blunted in dLAN hamsters, consistent with the observation that dLAN changed expression of the circadian clock gene, Period1. In addition, we demonstrated that expression levels of genes implicated in the photoperiodic response, Mel-1a melatonin receptor, Eyes absent 3, thyroid stimulating hormone receptor, gonadotropin-releasing hormone, and gonadotropin-inhibitory hormone, were higher in dLAN animals than those in short-day animals. These results suggest that dLAN disturbs the circadian clock function and affects the molecular mechanisms of the photoperiodic response.

  17. Artificial night lighting rather than traffic noise affects the daily timing of dawn and dusk singing in common European songbirds

    NARCIS (Netherlands)

    Da Silva, Arnaud; Samplonius, Jelmer Menno; Schlicht, Emmi; Valcu, Mihai; Kempenaers, Bart

    2014-01-01

    It is well established that artificial night lighting can influence animal orientation, but there is less information about its effects on other behaviors. Previous work suggested that light pollution can affect both seasonal and daily patterns of behavior. The aim of our study was to investigate

  18. Very low color-temperature organic light-emitting diodes for lighting at night

    Science.gov (United States)

    Jou, Jwo-Huei; Tang, Ming-Chun; Chen, Pin-Chu; Chen, Szu-Hao; Shen, Shih-Ming; Chen, Chien-Chih; Wang, Ching-Chiun; Chen, Chien-Tien

    2011-12-01

    Light sources with low color temperature (CT) are essential for their markedly less suppression effect on the secretion of melatonin, and high power efficiency is crucial for energy-saving. To provide visual comfort, the light source should also have a reasonably high color rendering index (CRI). In this report, we demonstrate the design and fabrication of low CT and high efficiency organic light-emitting diodes. The best resultant device exhibits a CT of 1,880 K, much lower than that of incandescent bulbs (2,000-2,500 K) and even as low as that of candles, (1,800-2,000 K), a beyond theoretical limit external quantum efficiency 22.7 %, and 36.0 lm/W at 100 cd/m 2. The high efficiency of the proposed device may be attributed to its interlayer, which helps effectively distribute the entering carriers into the available recombination zones.

  19. Melatonin the "light of night" in human biology and adolescent idiopathic scoliosis

    Directory of Open Access Journals (Sweden)

    Savvidou Olga D

    2007-04-01

    Full Text Available Abstract Melatonin "the light of night" is secreted from the pineal gland principally at night. The hormone is involved in sleep regulation, as well as in a number of other cyclical bodily activities and circadian rhythm in humans. Melatonin is exclusively involved in signalling the 'time of day' and 'time of year' (hence considered to help both clock and calendar functions to all tissues and is thus considered to be the body's chronological pacemaker or 'Zeitgeber'. The last decades melatonin has been used as a therapeutic chemical in a large spectrum of diseases, mainly in sleep disturbances and tumours and may play a role in the biologic regulation of mood, affective disorders, cardiovascular system, reproduction and aging. There are few papers regarding melatonin and its role in adolescent idiopathic scoliosis (AIS. Melatonin may play a role in the pathogenesis of scoliosis (neuroendocrine hypothesis but at present, the data available cannot clearly support this hypothesis. Uncertainties and doubts still surround the role of melatonin in human physiology and pathophysiology and future research is needed.

  20. Use of Circadian Lighting System to improve night shift alertness and performance of NRC Headquarters Operations Officers

    Energy Technology Data Exchange (ETDEWEB)

    Baker, T.L.; Morisseau, D.; Murphy, N.M. [ShiftWork Systems, Cambridge, MA (United States)] [and others

    1995-04-01

    The Nuclear Regulatory Commission`s (NRC) Headquarters Operations Officers (HOOs) receive and respond to events reported in the nuclear industry on a 24-hour basis. The HOOs have reported reduced alertness on the night shift, leading to a potential deterioration in their on-shift cognitive performance during the early morning hours. For some HOOs, maladaptation to the night shift was also reported to be the principal cause of: (a) reduced alertness during the commute to and from work, (b) poor sleep quality, and (c) personal lifestyle problems. ShiftWork Systems, Inc. (SWS) designed and installed a Circadian Lighting System (CLS) at both the Bethesda and Rockville HOO stations with the goal of facilitating the HOOs physiological adjustment to their night shift schedules. The data indicate the following findings: less subjective fatigue on night shifts; improved night shift alertness and mental performance; higher HOO confidence in their ability to assess event reports; longer, deeper and more restorative day sleep after night duty shifts; swifter adaptation to night work; and a safer commute, particularly for those with extensive drives.

  1. Reduced street lighting at night and health: A rapid appraisal of public views in England and Wales

    OpenAIRE

    Green, J.; Perkins, C.; Steinbach, R; P. Edwards

    2015-01-01

    Financial and carbon reduction incentives have prompted many local authorities to reduce street lighting at night. Debate on the public health implications has centred on road accidents, fear of crime and putative health gains from reduced exposure to artificial light. However, little is known about public views of the relationship between reduced street lighting and health. We undertook a rapid appraisal in eight areas of England and Wales using ethnographic data, a household survey and docu...

  2. A newly proposed disease condition produced by light exposure during night: asynchronization.

    Science.gov (United States)

    Kohyama, Jun

    2009-04-01

    The bedtime of preschoolers/pupils/students in Japan has become progressively later with the result sleep duration has become progressively shorter. With these changes, more than half of the preschoolers/pupils/students in Japan recently have complained of daytime sleepiness, while approximately one quarter of junior and senior high school students in Japan reportedly suffer from insomnia. These preschoolers/pupils/students may be suffering from behaviorally induced insufficient sleep syndrome due to inadequate sleep hygiene. If this diagnosis is correct, they should be free from these complaints after obtaining sufficient sleep by avoiding inadequate sleep hygiene. However, such a therapeutic approach often fails. Although social factors are often involved in these sleep disturbances, a novel clinical notion--asynchronization--can further a deeper understanding of the pathophysiology of these disturbances. The essence of asynchronization is a disturbance in various aspects (e.g., cycle, amplitude, phase and interrelationship) of the biological rhythms that normally exhibit circadian oscillation, presumably involving decreased activity of the serotonergic system. The major trigger of asynchronization is hypothesized to be a combination of light exposure during the night and a lack of light exposure in the morning. In addition to basic principles of morning light and an avoidance of nocturnal light exposure, presumable potential therapeutic approaches for asynchronization involve both conventional ones (light therapy, medications (hypnotics, antidepressants, melatonin, vitamin B12), physical activation, chronotherapy) and alternative ones (kampo, pulse therapy, direct contact, control of the autonomic nervous system, respiration (qigong, tanden breathing), chewing, crawling). A morning-type behavioral preference is described in several of the traditional textbooks for good health. The author recommends a morning-type behavioral lifestyle as a way to reduce

  3. Health consequences of electric lighting practices in the modern world: A report on the National Toxicology Program's workshop on shift work at night, artificial light at night, and circadian disruption.

    Science.gov (United States)

    Lunn, Ruth M; Blask, David E; Coogan, Andrew N; Figueiro, Mariana G; Gorman, Michael R; Hall, Janet E; Hansen, Johnni; Nelson, Randy J; Panda, Satchidananda; Smolensky, Michael H; Stevens, Richard G; Turek, Fred W; Vermeulen, Roel; Carreón, Tania; Caruso, Claire C; Lawson, Christina C; Thayer, Kristina A; Twery, Michael J; Ewens, Andrew D; Garner, Sanford C; Schwingl, Pamela J; Boyd, Windy A

    2017-12-31

    The invention of electric light has facilitated a society in which people work, sleep, eat, and play at all hours of the 24-hour day. Although electric light clearly has benefited humankind, exposures to electric light, especially light at night (LAN), may disrupt sleep and biological processes controlled by endogenous circadian clocks, potentially resulting in adverse health outcomes. Many of the studies evaluating adverse health effects have been conducted among night- and rotating-shift workers, because this scenario gives rise to significant exposure to LAN. Because of the complexity of this topic, the National Toxicology Program convened an expert panel at a public workshop entitled "Shift Work at Night, Artificial Light at Night, and Circadian Disruption" to obtain input on conducting literature-based health hazard assessments and to identify data gaps and research needs. The Panel suggested describing light both as a direct effector of endogenous circadian clocks and rhythms and as an enabler of additional activities or behaviors that may lead to circadian disruption, such as night-shift work and atypical and inconsistent sleep-wake patterns that can lead to social jet lag. Future studies should more comprehensively characterize and measure the relevant light-related exposures and link these exposures to both time-independent biomarkers of circadian disruption and biomarkers of adverse health outcomes. This information should lead to improvements in human epidemiological and animal or in vitro models, more rigorous health hazard assessments, and intervention strategies to minimize the occurrence of adverse health outcomes due to these exposures. Published by Elsevier B.V.

  4. Gender features and estrous cycle variations of nocturnal behavior of mice after a single exposure to light at night.

    Science.gov (United States)

    Datta, Siddhartha; Samanta, Diptaman; Sinha, Priyobrata; Chakrabarti, Nilkanta

    2016-10-01

    Light at night alters behavior and cognitive performances in rodents, the variations of which in gender and stages of reproductive cycle in females are elusive. Young mice habituated in light:dark (12:12h) cycle were given a single exposure of light (100lx) at early night for one hour duration followed by experimentations in open field (closed wall with circular big arena), elevated plus maze and square habituated field for memory performance using novel object recognition task. Light effects were compared with results found during without light conditions. Proestrous females appeared to have greater locomotor activity, less anxiety and better memory performance compared to the diestrous females at night without light exposure. The status of locomotor activity, anxiety and memory performance of male mice at night without light exposure appeared to be comparable to females where the stage of estrous cycle is important to characterize the nocturnal behavior of male mice. Light maximally affected proestrous females with decrease in locomotor activity, increase in anxiety and failure of memory performance. Male and diestrous female mice performed memory performance without alteration of locomotor activity and anxiety after exposure to light where males performed better memory performance with greater locomotor activity and more anxiety compared to that of diestrous females. The present study characterizes the mice nocturnal behavior with and without a single exposure to light stimuli with its gender features and estrous cycle variation. In addition, the study indicates an association of memory performance with locomotor activity and anxiety in mice nocturnal behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Fast low-level light pulses from the night sky observed with the SKYFLASH program

    Science.gov (United States)

    Winckler, J. R.; Franz, R. C.; Nemzek, R. J.

    1993-01-01

    This paper presents further discussion of and new data on fast subvisual increases in the luminosity of the night sky described in our previous papers. A detailed technical description of the simple telescopic photometers used in the project SKYFLASH and their mode of operation including the detection of polarized Rayleigh-scattered flashes is provided. Distant lightning storms account for many of the events, and the complex relations between short and long luminous pulses with and without sferics are shown by examples from a new computerized data system, supplemented by two low-light-level TV cameras. Of particular interest are the previously observed 'long' events having a slow rise and fall, 20-ms duration, and showing small polarization and no coincident sferic. A group of such events on September 22-23 during the invasion of U.S. coasts by Hurricane Hugo, is discussed in detail. The recently observed 'plume' cloud-top-to-stratosphere lightning event is suggested as a possible source type for these flashes. An alternative source may be exploding meteors, recently identified during SKYFLASH observations by low-light-level television techniques as the origin of some sky-wide flash events described herein.

  6. Dim light at night interferes with the development of the short-day phenotype and impairs cell-mediated immunity in Siberian hamsters (Phodopus sungorus).

    Science.gov (United States)

    Aubrecht, Taryn G; Weil, Zachary M; Nelson, Randy J

    2014-10-01

    Winter is a challenging time to survive and breed outside of the tropics. Animals use day length (photoperiod) to regulate seasonally appropriate adaptations in anticipation of challenging winter conditions. The net result of these photoperiod-mediated adjustments is enhanced immune function and increased survival. Thus, the ability to discriminate day length information is critical for survival and reproduction in small animals. However, during the past century, urban and suburban development has rapidly expanded and filled the night sky with light from various sources, obscuring crucial light-dark signals, which alters physiological interpretation of day lengths. Furthermore, reduced space, increased proximity to people, and the presence of light at night may act as stressors for small animals. Whereas acute stressors typically enhance immune responses, chronic exposure to stressors often impairs immune responses. Therefore, we hypothesized that the combination of dim light at night and chronic stress interferes with enhanced cell-mediated immunity observed during short days. Siberian hamsters (Phodopus sungorus) were assigned to short or long days with dark nights (0 lux) or dim (5 lux) light at night for 10 weeks. Following 2 weeks of chronic restraint (6 hr/day), a model of chronic stress, delayed type hypersensitivity (DTH) responses were assessed. Both dim light at night and restraint reduced the DTH response. Dim light at night during long nights produced an intermediate short day phenotype. These results suggest the constant presence of light at night could negatively affect survival of photoperiodic rodents by disrupting the timing of breeding and immune responses.

  7. Is Ambient Light during the High Arctic Polar Night Sufficient to Act as a Visual Cue for Zooplankton?

    Directory of Open Access Journals (Sweden)

    Jonathan H Cohen

    Full Text Available The light regime is an ecologically important factor in pelagic habitats, influencing a range of biological processes. However, the availability and importance of light to these processes in high Arctic zooplankton communities during periods of 'complete' darkness (polar night are poorly studied. Here we characterized the ambient light regime throughout the diel cycle during the high Arctic polar night, and ask whether visual systems of Arctic zooplankton can detect the low levels of irradiance available at this time. To this end, light measurements with a purpose-built irradiance sensor and coupled all-sky digital photographs were used to characterize diel skylight irradiance patterns over 24 hours at 79°N in January 2014 and 2015. Subsequent skylight spectral irradiance and in-water optical property measurements were used to model the underwater light field as a function of depth, which was then weighted by the electrophysiologically determined visual spectral sensitivity of a dominant high Arctic zooplankter, Thysanoessa inermis. Irradiance in air ranged between 1-1.5 x 10-5 μmol photons m-2 s-1 (400-700 nm in clear weather conditions at noon and with the moon below the horizon, hence values reflect only solar illumination. Radiative transfer modelling generated underwater light fields with peak transmission at blue-green wavelengths, with a 465 nm transmission maximum in shallow water shifting to 485 nm with depth. To the eye of a zooplankter, light from the surface to 75 m exhibits a maximum at 485 nm, with longer wavelengths (>600 nm being of little visual significance. Our data are the first quantitative characterisation, including absolute intensities, spectral composition and photoperiod of biologically relevant solar ambient light in the high Arctic during the polar night, and indicate that some species of Arctic zooplankton are able to detect and utilize ambient light down to 20-30m depth during the Arctic polar night.

  8. Circadian mechanisms in the regulation of melatonin synthesis: disruption with light at night and the pathophysiological consequences

    Directory of Open Access Journals (Sweden)

    Ahmet Korkmaz

    2011-02-01

    Full Text Available In the past two decades, the results of a number of epidemiological studies have uncovered an association between excessive light exposure at night and the prevalence of cancer. Whereas the evidence supporting this link is strongest between nighttime light and female breast and male prostate cancer, the frequency of other tumor types may also be elevated. Individuals who have the highest reported increase in cancer are chronic night shift workers and flight attendants who routinely fly across numerous time zones. There are at least two obvious physiological consequences of nighttime light exposure, i.e., a reduction in circulating melatonin levels and disruption of the circadian system (chronodisruption. Both these perturbations in experimental animals aggravate tumor growth. Melatonin has a long investigative history in terms of its ability to stymie the growth of many tumor types. Likewise, in the last decade chronodisruption has been unequivocally linked to a variety of abnormal metabolic conditions including excessive tumor growth. This brief review summarizes the processes by which light after darkness onset impedes melatonin production and disturbs circadian rhythms. The survey also reviews the evidence associating the ostensible danger of excessive nighttime light pollution to cancer risk. If an elevated tumor frequency is definitively proven to be a consequence of light at night and/or chronodisruption, it seems likely that cancer will not be the exclusive pathophysiological change associated with the rampant light pollution characteristic of modern societies. [J Exp Integr Med 2011; 1(1: 13-22

  9. Reduced street lighting at night and health: A rapid appraisal of public views in England and Wales.

    Science.gov (United States)

    Green, Judith; Perkins, Chloe; Steinbach, Rebecca; Edwards, Phil

    2015-07-01

    Financial and carbon reduction incentives have prompted many local authorities to reduce street lighting at night. Debate on the public health implications has centred on road accidents, fear of crime and putative health gains from reduced exposure to artificial light. However, little is known about public views of the relationship between reduced street lighting and health. We undertook a rapid appraisal in eight areas of England and Wales using ethnographic data, a household survey and documentary sources. Public concern focused on road safety, fear of crime, mobility and seeing the night sky but, for the majority in areas with interventions, reductions went unnoticed. However, more private concerns tapped into deep-seated anxieties about darkness, modernity 'going backwards', and local governance. Pathways linking lighting reductions and health are mediated by place, expectations of how localities should be lit, and trust in local authorities to act in the best interests of local communities.

  10. Urban light pollution - The effect of atmospheric aerosols on astronomical observations at night

    Science.gov (United States)

    Joseph, Joachim H.; Mekler, Yuri; Kaufman, Yoram J.

    1991-01-01

    The transfer of diffuse city light from a localized source through a dust-laden atmosphere with optical depth less than 0.5 has been analyzed in the source-observer plane on the basis of an approximate treatment. The effect on several types of astronomical observation at night has been studied, considering different size distributions and amounts as well as particle shapes of the aerosols. The analysis is made in terms of the signal-to-noise ratios for a given amount of aerosol. The model is applied to conditions at the Wise Astronomical Observatory in the Negev desert, and limiting backgrounds for spectroscopy, photometry, and photography of stars and extended objects have been calculated for a variety of signal-to-noise ratios. Applications to observations with different equipment at various distances from an urban area of any size are possible. Due to the use of signal-to-noise ratios, the conclusions are different for the different experimental techniques used in astronomy.

  11. Brief light exposure at night disrupts the circadian rhythms in eye growth and choroidal thickness in chicks.

    Science.gov (United States)

    Nickla, Debora L; Totonelly, Kristen

    2016-05-01

    Changes in ocular growth that lead to myopia or hyperopia are associated with alterations in the circadian rhythms in eye growth, choroidal thickness and intraocular pressure in animal models of emmetropization. Recent studies have shown that light at night has deleterious effects on human health, acting via "circadian disruptions" of various diurnal rhythms, including changes in phase or amplitude. The purpose of this study was to determine the effects of brief, 2-h episodes of light in the middle of the night on the rhythms in axial length and choroidal thickness, and whether these alter eye growth and refractive error in the chick model of myopia. Starting at 2 weeks of age, birds received 2 h of light between 12:00 am and 2:00 am for 7 days (n = 12; total hours of light: 14 h). Age-matched controls had a continuous dark night (n = 14; 14L/10D). Ocular dimensions were measured using high-frequency A-scan ultrasonography on the first day of the experiment, and again on day 7, at 6-h intervals, starting at noon (12 pm, 6 pm, 12 am, 6 am, 12 pm). Measurements during the night were done under a photographic safe-light. These data were used to determine rhythm parameters of phase and amplitude. 2 groups of birds, both experimental (light at night) and control, were measured with ultrasound at various intervals over the course of 4 weeks to determine growth rates. Refractive errors were measured in 6 experimental and 6 control birds at the end of 2 weeks. Eyes of birds in a normal L/D cycle showed sinusoidal 24-h period diurnal rhythms in axial length and choroid thickness. Light in the middle of the night caused changes in both the rhythms in axial length and choroidal thickness, such that neither could be fit to a sine function having a period of 24 h. Light caused an acute, transient stimulation in ocular growth rate in the subsequent 6-h period (12 am-6 am), that may be responsible for the increased growth rate seen 4 weeks later, and the more

  12. Association between light at night, melatonin secretion, sleep deprivation, and the internal clock: Health impacts and mechanisms of circadian disruption.

    Science.gov (United States)

    Touitou, Yvan; Reinberg, Alain; Touitou, David

    2017-03-15

    Exposure to Artificial Light At Night (ALAN) results in a disruption of the circadian system, which is deleterious to health. In industrialized countries, 75% of the total workforce is estimated to have been involved in shift work and night work. Epidemiologic studies, mainly of nurses, have revealed an association between sustained night work and a 50-100% higher incidence of breast cancer. The potential and multifactorial mechanisms of the effects include the suppression of melatonin secretion by ALAN, sleep deprivation, and circadian disruption. Shift and/or night work generally decreases the time spent sleeping, and it disrupts the circadian time structure. In the long run, this desynchronization is detrimental to health, as underscored by a large number of epidemiological studies that have uncovered elevated rates of several diseases, including cancer, diabetes, cardiovascular risks, obesity, mood disorders and age-related macular degeneration. It amounts to a public health issue in the light of the very substantial number of individuals involved. The IARC has classified shift work in group 2A of "probable carcinogens to humans" since "they involve a circadian disorganization". Countermeasures to the effects of ALAN, such as melatonin, bright light, or psychotropic drugs, have been proposed as a means to combat circadian clock disruption and improve adaptation to shift and night work. We review the evidence for the ALAN impacts on health. Furthermore, we highlight the importance of an in-depth mechanistic understanding to combat the detrimental properties of exposure to ALAN and develop strategies of prevention. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Using Light-at-Night (LAN) Satellite Data for Identifying Clusters of Economic Activities in Europe

    Science.gov (United States)

    Rybnikova, N. A.; Portnov, B. A.

    2015-04-01

    Enterprises organized in clusters are often efficient in stimulating urban development, productivity and profit outflows. Identifying clusters of economic activities (EAs) thus becomes an important step in devising regional development policies, aimed at facilitating regional economic development. However, a major problem with cluster identification stems from limited reporting of specific EAs by individual countries and administrative entities. Even Eurostat, which maintains most advances regional databases, provides data for less than 50% of all regional subdivisions of the 3rd tier of the Nomenclature of Territorial Units for Statistics (NUTS3). Such poor reporting impedes identification of EA clusters and economic forces behind them. In this study, we test a possibility that missing data on geographic concentrations of EAs can be reconstructed using Light-at-Night (LAN) satellite measurements, and that such reconstructed data can then be used for the identification of EA clusters. As we hypothesize, LAN, captured by satellite sensors, is characterized by different intensity, depending on its source - production facilities, services, etc., - and this information can be used for EA identification. The study was carried out in three stages. First, using nighttime satellite images, we determined what types of EAs can be identified, with a sufficient degree of accuracy, by LAN they emit. Second, we calculated multivariate statistical models, linking EAs concentrations with LAN intensities and several locational and development attributes of NUTS3 regions in Europe. Next, using the obtained statistical models, we restored missing data on EAs across NUTS3 regions in Europe and identified clusters of EAs, using spatial analysis tools.

  14. Chronic dim light at night provokes reversible depression-like phenotype: possible role for TNF.

    Science.gov (United States)

    Bedrosian, T A; Weil, Z M; Nelson, R J

    2013-08-01

    The prevalence of major depression has increased in recent decades and women are twice as likely as men to develop the disorder. Recent environmental changes almost certainly have a role in this phenomenon, but a complete set of contributors remains unspecified. Exposure to artificial light at night (LAN) has surged in prevalence during the past 50 years, coinciding with rising rates of depression. Chronic exposure to LAN is linked to increased risk of breast cancer, obesity and mood disorders, although the relationship to mood is not well characterized. In this study, we investigated the effects of chronic exposure to 5 lux LAN on depression-like behaviors in female hamsters. Using this model, we also characterized hippocampal brain-derived neurotrophic factor expression and hippocampal dendritic morphology, and investigated the reversibility of these changes 1, 2 or 4 weeks following elimination of LAN. Furthermore, we explored the mechanism of action, focusing on hippocampal proinflammatory cytokines given their dual role in synaptic plasticity and the pathogenesis of depression. Using reverse transcription-quantitative PCR, we identified a reversible increase in hippocampal tumor necrosis factor (TNF), but not interleukin-1β, mRNA expression in hamsters exposed to LAN. Direct intracerebroventricular infusion of a dominant-negative inhibitor of soluble TNF, XPro1595, prevented the development of depression-like behavior under LAN, but had no effect on dendritic spine density in the hippocampus. These results indicate a partial role for TNF in the reversible depression-like phenotype observed under chronic dim LAN. Recent environmental changes, such as LAN exposure, may warrant more attention as possible contributors to rising rates of mood disorders.

  15. Effects of Red Light Night Break Treatment on Growth and Flowering of Tomato Plants

    Directory of Open Access Journals (Sweden)

    Kai eCao

    2016-04-01

    Full Text Available Compact and healthy young plants increase crop production and improve vegetable quality. Adverse climatic conditions and shading can cause young plants to become elongated and spindly. We investigated the effects of night break (NB treatments on tomato plants using red light (RL with an intensity of 20 µmol•m2•s-1. Tomato plants were subjected to NB treatments with different frequencies ranging from every 1, 2, 3, and 4 h, and plant growth, flowering, and yield were monitored. The results showed that with the increase of RL NB frequency, plant height decreased, stem diameter increased, and flower initiation delayed, the content of indole-3-acetic acid (IAA and gibberellin 3 (GA3 in the leaf and stem declined. When the RL NB frequency was every 1 h, the heights of tomato plant decreased by 32.73% compared with the control, the diameter of tomato plants increased by 27.09% compared with the control, the number of leaves produced before flowering increased to 11, compared with 8 in the control, the contents of IAA and GA3 in the leaf decreased by 33.3% and 41.29% respectively compared with the control, the contents of IAA and GA3 in the stem decreased by 56.04% and 57.14% respectively compared with the control. After RL NB treatments, tomato plants were transplanted into a solar greenhouse to evaluate tomato yield. When tomato plants pre-treated with RL NB, per tomato fresh weight of the first spica increased with the increase of RL NB frequencies. These results indicate that more compact and healthier tomato plants could be gotten by RL NB treatments and improve tomato early yield.

  16. Effects of Red Light Night Break Treatment on Growth and Flowering of Tomato Plants.

    Science.gov (United States)

    Cao, Kai; Cui, Lirong; Ye, Lin; Zhou, Xiaoting; Bao, Encai; Zhao, Hailiang; Zou, Zhirong

    2016-01-01

    Compact and healthy young plants increase crop production and improve vegetable quality. Adverse climatic conditions and shading can cause young plants to become elongated and spindly. We investigated the effects of night break (NB) treatments on tomato plants using red light (RL) with an intensity of 20 μmol·m(2)·s(-1). Tomato plants were subjected to NB treatments with different frequencies ranging from every 1, 2, 3, and 4 h, and plant growth, flowering, and yield were monitored. The results showed that with the increase of RL NB frequency, plant height decreased, stem diameter increased, and flower initiation delayed, the content of indole-3-acetic acid (IAA) and gibberellin 3 (GA3) in the leaf and stem declined. When the RL NB frequency was every 1 h, the heights of tomato plant decreased by 32.73% compared with the control, the diameter of tomato plants increased by 27.09% compared with the control, the number of leaves produced before flowering increased to 11, compared with 8 in the control, the contents of IAA and GA3 in the leaf decreased by 33.3 and 41.29% respectively compared with the control, the contents of IAA and GA3 in the stem decreased by 56.04 and 57.14% respectively compared with the control. After RL NB treatments, tomato plants were transplanted into a solar greenhouse to evaluate tomato yield. When tomato plants pre-treated with RL NB, per tomato fresh weight of the first spica increased with the increase of RL NB frequencies. These results indicate that more compact and healthier tomato plants could be gotten by RL NB treatments and improve tomato early yield.

  17. The Souls’Journey into Light--On Eugene O’Neill’s Long Days Journey into Night

    Institute of Scientific and Technical Information of China (English)

    万红芳

    2013-01-01

    This paper aims to find a glimmer of light and hope from Eugene O’Neill’s tragedy: Long Days Journey into Night. The Tyrones’ periodic quarrel from dawn to dark is a journey into torture whereas it can also been seen as an indication of the unremitting hope for home. Behind the uneasy tensions of the characters who still cry for individual salvation, lies a world where the conflict between reality and fantasy can be resolved through love and reconciliation.

  18. Poverty assessment using DMSP/OLS night-time light satellite imagery at a provincial scale in China

    Science.gov (United States)

    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.

  19. Modeling the Driver's Recognitive Characteristics to Crossing Pedestrians at Night for the Maximum Speed Limit and Lighting Index in China

    Directory of Open Access Journals (Sweden)

    Liang Xu

    2015-01-01

    Full Text Available Aiming to reduce the number of crashes caused by speeding at night on road section with a crosswalk, a study was conducted on the maximum speed limit and safe average luminance at night. In order to investigate the potential relationship between drivers’ recognitive characteristics and driving speed under different road lighting features, data of remaining driving time (period from the time that crossing pedestrian is recognized to the time that vehicle arrives at crosswalk with an uniform speed were recorded. The results of the data analysis show that it is more difficult for divers to recognize crossing pedestrian at night when a single pedestrian is statistic and wears dark clothes. The remaining driving time decreases with the increase of driving speed and the decrease of road luminance. With the collected data, several multivariate nonlinear regression models were established to capture the relationship among the variables of remaining driving time at night, the driving speed, and the average luminance. Then the modeling results were used to develop the reasonable speed limit and safe average luminance by physical equations. The case studies are also introduced at the end of the paper.

  20. Artificial light at night disrupts sleep in female great tits (Parus major) during the nestling period, and is followed by a sleep rebound.

    Science.gov (United States)

    Raap, Thomas; Pinxten, Rianne; Eens, Marcel

    2016-08-01

    Artificial light at night has been linked to a wide variety of physiological and behavioural consequences in humans and animals. Given that little is known about the impact of light pollution on sleep in wild animals, we tested how experimentally elevated light levels affected sleep behaviour of female songbirds rearing 10 day old chicks. Using a within-subject design, individual sleep behaviour was observed over three consecutive nights in great tits (Parus major), with females sleeping in a natural dark situation on the first and third night, whereas on the second night they were exposed to a light-emitting diode (1.6 lux). Artificial light in the nest box dramatically and significantly affected sleep behaviour, causing females to fall asleep later (95 min; while entry time was unaffected), wake up earlier (74 min) and sleep less (56%). Females spent a greater proportion of the night awake and the frequency of their sleep bouts decreased, while the length of their sleep bouts remained equal. Artificial light also increased begging of chicks at night, which may have contributed to the sleep disruption in females or vice versa. The night following the light treatment, females slept 25% more compared to the first night, which was mainly achieved by increasing the frequency of sleep bouts. Although there was a consistent pattern in how artificial light affected sleep, there was also large among-individual variation in how strongly females were affected. When comparing current results with a similar experiment during winter, our results highlight differences in effects between seasons and underscore the importance of studying light pollution during different seasons. Our study shows that light pollution may have a significant impact on sleep behaviour in free-living animals during the reproductive season, which may provide a potential mechanism by which artificial light affects fitness.

  1. Water repellent spray-type encapsulation of quantum dot light-emitting diodes using super-hydrophobic self-assembled nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Han, Junebeom; Bong, Jihye; Lim, Taekyung [Department of Physics, Kyonggi University, Suwon, Gyeonggi-Do, 443-760 (Korea, Republic of); Lee, Ki-Heon; Yang, Heesun [Department of Materials Science and Engineering, Hongik University, Seoul, 121-791 (Korea, Republic of); Ju, Sanghyun, E-mail: shju@kgu.ac.kr [Department of Physics, Kyonggi University, Suwon, Gyeonggi-Do, 443-760 (Korea, Republic of)

    2015-10-30

    Graphical abstract: - Highlights: • A spray-type encapsulation method capable of being applied to flexible and concave/convex substrates has been demonstrated to have no negative effect on the luminance and efficiency of QD-LEDs. • The highly dense thin-film provided by SAM-NP encapsulation can increase the effective lifetime of QD-LED devices by a factor of 16. • The QD-LEDs with SAM-NP encapsulation were found to have an effective lifetime in ambient air and a stable light emission in water. - Abstract: We have developed a spray-type encapsulation method for quantum dot light-emitting diode (QD-LED) displays designed to prevent the penetration of oxygen and moisture in ambient air and repel water. The non-wettability and oxygen/moisture repellency afforded by the super-hydrophobic (contact angle of ∼158°) self-assembled Al{sub 2}O{sub 3} nanoparticles (SAM-NP) is attributed to a reduction in the number of defects sites such as pin-holes or cracks during the formation of the thin-film. The QD-LEDs with SAM-NP encapsulation were found to have an effective lifetime in ambient air and a stable light emission in water compared to those of equivalent QD-LEDs without encapsulation.

  2. Artificial light at night affects body mass but not oxidative status in free-living nestling songbirds: an experimental study

    Science.gov (United States)

    Raap, Thomas; Casasole, Giulia; Costantini, David; Abdelgawad, Hamada; Asard, Han; Pinxten, Rianne; Eens, Marcel

    2016-10-01

    Artificial light at night (ALAN), termed light pollution, is an increasingly important anthropogenic environmental pressure on wildlife. Exposure to unnatural lighting environments may have profound effects on animal physiology, particularly during early life. Here, we experimentally investigated for the first time the impact of ALAN on body mass and oxidative status during development, using nestlings of a free-living songbird, the great tit (Parus major), an important model species. Body mass and blood oxidative status were determined at baseline (=13 days after hatching) and again after a two night exposure to ALAN. Because it is very difficult to generalise the oxidative status from one or two measures we relied on a multi-biomarker approach. We determined multiple metrics of both antioxidant defences and oxidative damage: molecular antioxidants GSH, GSSG; antioxidant enzymes GPX, SOD, CAT; total non-enzymatic antioxidant capacity and damage markers protein carbonyls and TBARS. Light exposed nestlings showed no increase in body mass, in contrast to unexposed individuals. None of the metrics of oxidative status were affected. Nonetheless, our study provides experimental field evidence that ALAN may negatively affect free-living nestlings’ development and hence may have adverse consequences lasting throughout adulthood.

  3. Event Detection Using Mobile Phone Mass GPS Data and Their Reliavility Verification by Dmsp/ols Night Light Image

    Science.gov (United States)

    Yuki, Akiyama; Satoshi, Ueyama; Ryosuke, Shibasaki; Adachi, Ryuichiro

    2016-06-01

    In this study, we developed a method to detect sudden population concentration on a certain day and area, that is, an "Event," all over Japan in 2012 using mass GPS data provided from mobile phone users. First, stay locations of all phone users were detected using existing methods. Second, areas and days where Events occurred were detected by aggregation of mass stay locations into 1-km-square grid polygons. Finally, the proposed method could detect Events with an especially large number of visitors in the year by removing the influences of Events that occurred continuously throughout the year. In addition, we demonstrated reasonable reliability of the proposed Event detection method by comparing the results of Event detection with light intensities obtained from the night light images from the DMSP/OLS night light images. Our method can detect not only positive events such as festivals but also negative events such as natural disasters and road accidents. These results are expected to support policy development of urban planning, disaster prevention, and transportation management.

  4. EVENT DETECTION USING MOBILE PHONE MASS GPS DATA AND THEIR RELIAVILITY VERIFICATION BY DMSP/OLS NIGHT LIGHT IMAGE

    Directory of Open Access Journals (Sweden)

    A. Yuki

    2016-06-01

    Full Text Available In this study, we developed a method to detect sudden population concentration on a certain day and area, that is, an “Event,” all over Japan in 2012 using mass GPS data provided from mobile phone users. First, stay locations of all phone users were detected using existing methods. Second, areas and days where Events occurred were detected by aggregation of mass stay locations into 1-km-square grid polygons. Finally, the proposed method could detect Events with an especially large number of visitors in the year by removing the influences of Events that occurred continuously throughout the year. In addition, we demonstrated reasonable reliability of the proposed Event detection method by comparing the results of Event detection with light intensities obtained from the night light images from the DMSP/OLS night light images. Our method can detect not only positive events such as festivals but also negative events such as natural disasters and road accidents. These results are expected to support policy development of urban planning, disaster prevention, and transportation management.

  5. Circadian disruption induced by light-at-night accelerates aging and promotes tumorigenesis in young but not in old rats

    Science.gov (United States)

    Vinogradova, Irina A.; Anisimov, Vladimir N.; Bukalev, Andrey V.; Ilyukha, Viktor A.; Khizhkin, Evgeniy A.; Lotosh, Tatiana A.; Semenchenko, Anna V.; Zabezhinski, Mark A.

    2010-01-01

    We evaluated the effect of exposure to constant light started at the age of 1 month and at the age of 14 months on the survival, life span, tumorigenesis and age-related dynamics of antioxidant enzymes activity in various organs in comparison to the rats maintained at the standard (12:12 light/dark) light/dark regimen. We found that exposure to constant light started at the age of 1 month accelerated spontaneous tumorigenesis and shortened life span both in male and female rats as compared to the standard regimen. At the same time, the exposure to constant light started at the age of 14 months failed to influence survival of male and female rats. While delaying tumors in males, constant light accelerated tumors in females. We conclude that circadian disruption induced by light-at-night started at the age of 1 month accelerates aging and promotes tumorigenesis in rats, however failed affect survival when started at the age of 14 months. PMID:20354269

  6. LIGHT EXPOSURE ASSESSMENT OF DANISH INDOOR, OUTDOOR AND NIGHT-SHIFT WORKERS

    DEFF Research Database (Denmark)

    Markvart, Jakob

    2016-01-01

    A research talk about: • The Lux@r project - The context of this talk • Light and light exposure - What When and Where • Light as a “one-dimensional unit” – things that matters: 1. Spectral sensitivity 2. Spatial sensitivity......A research talk about: • The Lux@r project - The context of this talk • Light and light exposure - What When and Where • Light as a “one-dimensional unit” – things that matters: 1. Spectral sensitivity 2. Spatial sensitivity...

  7. Night of Darkness Campaign: Make Light Pollution Something Everybody Cares About

    Science.gov (United States)

    Pas, Friedel

    2015-03-01

    To battle light pollution issues, influence the market so that customers request only good lighting. An important factor in doing this is to convince decision makers that light pollution is something the whole society cares about. This article gives an overview of an existing campaign that does this and emphasizes some important factors to consider in your campaign.

  8. Transient anhedonia phenotype and altered circadian timing of behaviour during night-time dim light exposure in Per3−/− mice, but not wildtype mice

    Science.gov (United States)

    Martynhak, Bruno Jacson; Hogben, Alexandra L.; Zanos, Panos; Georgiou, Polymnia; Andreatini, Roberto; Kitchen, Ian; Archer, Simon N.; von Schantz, Malcolm; Bailey, Alexis; van der Veen, Daan R.

    2017-01-01

    Industrialisation greatly increased human night-time exposure to artificial light, which in animal models is a known cause of depressive phenotypes. Whilst many of these phenotypes are ‘direct’ effects of light on affect, an ‘indirect’ pathway via altered sleep-wake timing has been suggested. We have previously shown that the Period3 gene, which forms part of the biological clock, is associated with altered sleep-wake patterns in response to light. Here, we show that both wild-type and Per3−/− mice showed elevated levels of circulating corticosterone and increased hippocampal Bdnf expression after 3 weeks of exposure to dim light at night, but only mice deficient for the PERIOD3 protein (Per3−/−) exhibited a transient anhedonia-like phenotype, observed as reduced sucrose preference, in weeks 2–3 of dim light at night, whereas WT mice did not. Per3−/− mice also exhibited a significantly smaller delay in behavioural timing than WT mice during weeks 1, 2 and 4 of dim light at night exposure. When treated with imipramine, neither Per3−/− nor WT mice exhibited an anhedonia-like phenotype, and neither genotypes exhibited a delay in behavioural timing in responses to dLAN. While the association between both Per3−/− phenotypes remains unclear, both are alleviated by imipramine treatment during dim night-time light. PMID:28071711

  9. Analysis of circadian properties and healthy levels of blue light from smartphones at night.

    Science.gov (United States)

    Oh, Ji Hye; Yoo, Heeyeon; Park, Hoo Keun; Do, Young Rag

    2015-06-18

    This study proposes representative figures of merit for circadian and vision performance for healthy and efficient use of smartphone displays. The recently developed figures of merit for circadian luminous efficacy of radiation (CER) and circadian illuminance (CIL) related to human health and circadian rhythm were measured to compare three kinds of commercial smartphone displays. The CIL values for social network service (SNS) messenger screens from all three displays were higher than 41.3 biolux (blx) in a dark room at night, and the highest CIL value reached 50.9 blx. These CIL values corresponded to melatonin suppression values (MSVs) of 7.3% and 11.4%, respectively. Moreover, smartphone use in a bright room at night had much higher CIL and MSV values (58.7 ~ 105.2 blx and 15.4 ~ 36.1%, respectively). This study also analyzed the nonvisual and visual optical properties of the three smartphone displays while varying the distance between the screen and eye and controlling the brightness setting. Finally, a method to possibly attenuate the unhealthy effects of smartphone displays was proposed and investigated by decreasing the emitting wavelength of blue LEDs in a smartphone LCD backlight and subsequently reducing the circadian effect of the display.

  10. Analysis of circadian properties and healthy levels of blue light from smartphones at night

    Science.gov (United States)

    Oh, Ji Hye; Yoo, Heeyeon; Park, Hoo Keun; Do, Young Rag

    2015-06-01

    This study proposes representative figures of merit for circadian and vision performance for healthy and efficient use of smartphone displays. The recently developed figures of merit for circadian luminous efficacy of radiation (CER) and circadian illuminance (CIL) related to human health and circadian rhythm were measured to compare three kinds of commercial smartphone displays. The CIL values for social network service (SNS) messenger screens from all three displays were higher than 41.3 biolux (blx) in a dark room at night, and the highest CIL value reached 50.9 blx. These CIL values corresponded to melatonin suppression values (MSVs) of 7.3% and 11.4%, respectively. Moreover, smartphone use in a bright room at night had much higher CIL and MSV values (58.7 ~ 105.2 blx and 15.4 ~ 36.1%, respectively). This study also analyzed the nonvisual and visual optical properties of the three smartphone displays while varying the distance between the screen and eye and controlling the brightness setting. Finally, a method to possibly attenuate the unhealthy effects of smartphone displays was proposed and investigated by decreasing the emitting wavelength of blue LEDs in a smartphone LCD backlight and subsequently reducing the circadian effect of the display.

  11. Rainfall simulation experiments and Water Drop Penetration Time measurements shed light on the impact of water repellency on soils under organic farming management in Eastern Spain

    Science.gov (United States)

    Cerdà, Artemi; González, Óscar; León, Javier; Jordán, Antonio

    2015-04-01

    Water repellency is a well-know soil property since the research of professor Stefan Helmut Doerr recovered and powered the research developed by professor DeBano (Atanassova and Doerr, 2011; ; Jordán et al., 2011; Bodí et al., 2012; González Peñaloza et al., 2012 Bodí et al., 2013; García Moreno et al., 2013; Jordán et al., 2013; Badía-Villas et al., 2014; Jordán et al., 2013; Jiménez Morillo et al., 2015). However, little is known about the impact of water repellency in surface runoff generation, although usually is accepted that when more soil water repellent is a soil, higher will be the surface runoff discharge (Stoff et al., 2011; Madsen et al., 2011; León et al., 2013; Lozano et al., 2013; Mataix-Solera et al., 2013; Santos et al., 2015). And the impact of the water repellency and then the higher surface wash discharge can trigger high erosion rates (Kröpfl et al., 2013; Mandal and Sharda 2013; Zhao et al., 2013). However these relationships were not demonstrated as the most water repellent soils are the one with high organic contents, and those soils do not have soil losses, probably due to the high infiltration rates due to the macropore flow. Rainfall simulation experiments can shed light in the runoff generation mechanism as they can control the rainfall intensity (Bodí et al., 2012; Iserloh et al., 2012; Iserloh et al., 2013), and inform about the main mechanism of the soil erosion process Cerdà and Jurgensen, 2011; Daugherty et al., 2011; Podwojewski et al., 2011; Dunkerley, 2012; Garel et al., 2012; Jouquet et al., 2012; Kibet et al., 2013; Butzen et al., 2014; Ma et al., 2014; Martínez Murillo et al., 2013). To determine the relationship between surface runoff generated under simulated rainfall (Cerdà, 1988a; 1988b; Cerdà et al., 1998; Ziadat and Taimeh, 2013) with a small rainfall simulator (0.25 m2) and water repellency measurements with the Water Drop Penetration time methods were done (Bodí et al., 2012). The results show that

  12. Exposure of tropical ecosystems to artificial light at night: Brazil as a case study

    Science.gov (United States)

    Bennie, Jon; Mantovani, Waldir; Gaston, Kevin J.

    2017-01-01

    Artificial nighttime lighting from streetlights and other sources has a broad range of biological effects. Understanding the spatial and temporal levels and patterns of this lighting is a key step in determining the severity of adverse effects on different ecosystems, vegetation, and habitat types. Few such analyses have been conducted, particularly for regions with high biodiversity, including the tropics. We used an intercalibrated version of the Defense Meteorological Satellite Program’s Operational Linescan System (DMSP/OLS) images of stable nighttime lights to determine what proportion of original and current Brazilian vegetation types are experiencing measurable levels of artificial light and how this has changed in recent years. The percentage area affected by both detectable light and increases in brightness ranged between 0 and 35% for native vegetation types, and between 0 and 25% for current vegetation (i.e. including agriculture). The most heavily affected areas encompassed terrestrial coastal vegetation types (restingas and mangroves), Semideciduous Seasonal Forest, and Mixed Ombrophilous Forest. The existing small remnants of Lowland Deciduous and Semideciduous Seasonal Forests and of Campinarana had the lowest exposure levels to artificial light. Light pollution has not often been investigated in developing countries but our data show that it is an environmental concern. PMID:28178352

  13. Association between light exposure at night and insomnia in the general elderly population: the HEIJO-KYO cohort.

    Science.gov (United States)

    Obayashi, Kenji; Saeki, Keigo; Kurumatani, Norio

    2014-11-01

    Chronic circadian misalignment between the internal and environmental rhythms, which is typically related to night-shift work and clock-gene variants, is associated with disruption of suprachiasmatic nucleus function and increased risk of insomnia. Under controlled laboratory conditions, light at night (LAN) suppresses melatonin secretion, delays the internal biological rhythm, and reduces sleepiness. Therefore, LAN exposure may cause circadian misalignment and insomnia, though it remains unclear in real-life situations whether LAN exposure is associated with insomnia. To evaluate an association between LAN exposure and sleep quality in home settings, we conducted a cross-sectional community-based study in 857 elderly individuals (mean age, 72.2 years). We evaluated bedroom light intensity using a light meter and subjectively and objectively measured sleep quality using the Pittsburgh Sleep Quality Index and an actigraph, respectively, along with urinary 6-sulfatoxymelatonin excretion. Compared with the lowest quartile group of LAN intensity, the highest quartile group revealed a significantly higher odds ratio (OR) for subjective insomnia in a multivariate model adjusted for age, gender, body mass index, daytime physical activity, urinary 6-sulfatoxymelatonin excretion, bedtime, rising time, and day length (adjusted OR, 1.61, 95% confidence interval, 1.05-2.45, p=0.029). In addition, higher OR for subjective insomnia was significantly associated with the increase in quartiles of LAN intensity (ptrend=0.043). Consistently, we observed significant association trends between the increase in quartiles of LAN intensity and poorer actigraphic sleep quality, including decreased sleep efficiency, prolonged sleep-onset latency, increased wake-after-sleep onset, shortened total sleep time, and delayed sleep-mid time in multivariate models adjusted for the covariates mentioned above (all ptrendassociated with both subjectively and objectively measured sleep quality in a

  14. The influence of red light exposure at night on circadian metabolism and physiology in Sprague-Dawley rats.

    Science.gov (United States)

    Dauchy, Robert T; Wren, Melissa A; Dauchy, Erin M; Hoffman, Aaron E; Hanifin, John P; Warfield, Benjamin; Jablonski, Michael R; Brainard, George C; Hill, Steven M; Mao, Lulu; Dobek, Georgina L; Dupepe, Lynell M; Blask, David E

    2015-01-01

    Early studies on rodents showed that short-term exposure to high-intensity light (> 70 lx) above 600 nm (red-appearing) influences circadian neuroendocrine and metabolic physiology. Here we addressed the hypothesis that long-term, low-intensity red light exposure at night (rLEN) from a 'safelight' emitting no light below approximately 620 nm disrupts the nocturnal circadian melatonin signal as well as circadian rhythms in circulating metabolites, related regulatory hormones, and physi- ologic parameters. Male Sprague-Dawley rats (n = 12 per group) were maintained on control 12:12-h light:dark (300 lx; lights on, 0600) or experimental 12:12 rLEN (8.1 lx) lighting regimens. After 1 wk, rats underwent 6 low-volume blood draws via cardiocentesis (0400, 0800, 1200, 1600, 2000, and 2400) over a 4-wk period to assess arterial plasma melatonin, total fatty acid, glucose, lactic acid, pO2, pCO2, insulin, leptin and corticosterone concentrations. Results revealed plasma melatonin levels (mean ± 1 SD) were high in the dark phase (197.5 ± 4.6 pg/mL) and low in the light phase (2.6 ± 1.2 pg/mL) of control condi- tions and significantly lower than controls under experimental conditions throughout the 24-h period (P < 0.001). Prominent circadian rhythms of plasma levels of total fatty acid, glucose, lactic acid, pO2, pCO2, insulin, leptin, and corticosterone were significantly (P < 0.05) disrupted under experimental conditions as compared with the corresponding entrained rhythms under control conditions. Therefore, chronic use of low-intensity rLEN from a common safelight disrupts the circadian organization of neuroendocrine, metabolic, and physiologic parameters indicative of animal health and wellbeing.

  15. RESEARCH OF NIGHT LIGHT EFFECTS ON COLORIMETRIC CHARACTERISTICS OF IMAGE PERCEIVED BY THE PILOT IN AN AIRCRAFT COCKPIT

    Directory of Open Access Journals (Sweden)

    I. O. Zharinov

    2015-09-01

    Full Text Available Subject of Research. The influence of radiation spectra from the source of artificial night light on colorimetric characteristics of image perceived by the pilot in the aircraft cockpit has been studied. The image is displayed on the LCD screen of multifunctional color indication equipment unit. Night illumination of the cockpit is performed with the use of artificial lamps of red, green, blue and, rarely, white light. Method. Any given color to be displayed on the screen is perceived by an observer differently with presence and absence of external illumination. When external light of white color is used, perceived color depends upon color temperature of the light source; if illumination source has any arbitrary spectral characteristics, then perceivable color depends upon whole spectral content of the used source. The color, perceived by an observer, is formed as the mixture of the color displayed on the screen (image element color with the color presented by diffuse reflection of external illumination source from the surface of the screen. The brightness of both colors is added. Mathematical expressions, that define calculation rule for chromaticity coordinates of color perceived by an observer, are based on the Grassmann’s law of additive color mixing. Quantitative analysis of the effect, caused by radiation spectra from an external source of artificial light on color gamut area, corresponding to image, perceived by an observer, has been performed through simulation in MathCad 15.0. Main Results. It was shown, that the color palette of on-board indication equipment, obtained on automated working place for any preset source of external illumination of fluorescent spectrum, corresponding to white light, is not usable correctly in the aircraft night flight mode. An observer loses ability to perceive properly saturated primary colors of red and blue in the case of green-blue light source of external illumination; and the same issue occurs with

  16. Abscisic acid metabolism and anthocyanin synthesis in grape skin are affected by light emitting diode (LED) irradiation at night.

    Science.gov (United States)

    Kondo, Satoru; Tomiyama, Hiroyuki; Rodyoung, Abhichartbut; Okawa, Katsuya; Ohara, Hitoshi; Sugaya, Sumiko; Terahara, Norihiko; Hirai, Nobuhiro

    2014-06-15

    The effects of blue and red light irradiation at night on abscisic acid (ABA) metabolism and anthocyanin synthesis were examined in grape berries. The expressions of VlMYBA1-2, VlMYBA2, UDP-glucose-flavonoid 3-O-glucosyltransferase (VvUFGT), 9-cis-epoxycarotenoid dioxygenase (VvNCED1), and ABA 8'-hydroxylase (VvCYP707A1) were also investigated. Endogenous ABA, its metabolite phaseic acid (PA), and the expressions of VvNCED1 and VvCYP707A1 were highest in red light-emitting diode (LED)-treated skin. In contrast, anthocyanin concentrations were highest in blue LED-treated skin, followed by red LED treatment. However, the expressions of VlMYBA1-2, VlMYBA2, and VvUFGT did not necessarily coincide with anthocyanin concentrations. The quality of coloring may depend on the amount of malvidin-based anthocyanin, which increased toward harvest in blue and red LED-treated skin, unlike in untreated controls. An increase in sugars was also observed in blue and red LED-treated skin. These results suggest that blue LED irradiation at night may be effective in increasing anthocyanin and sugar concentrations in grape berries. However, there is evidence that another factor may influence anthocyanin concentrations in grape berry skin significantly more than endogenous ABA: ABA concentrations were highest in red LED-treated skin, which had lower anthocyanin concentrations than blue LED-treated skin. Copyright © 2014 Elsevier GmbH. All rights reserved.

  17. Self-reported Impacts of LED Lighting Technology Compared to Fuel-based Lighting on Night Market Business Prosperity in Kenya

    Energy Technology Data Exchange (ETDEWEB)

    Johnstone, Peter; Jacobson, Arne; Mills, Evan; Mumbi, Maina

    2009-02-11

    The notion of"productive use" is often invoked in discussions about whether new technologies improve productivity or otherwise enhance commerce in developing-country contexts. It an elusive concept,especially when quantitative measures are sought. Improved and more energy efficient illumination systems for off-gridapplication--the focus of the Lumina Project--provide a case in which a significant productivity benefit can be imagined, given the importance of light to the successful performance of many tasks, and the very low quality of baseline illumination provided by flame-based source. This Research Note summarizes self-reported quantitative and qualitative impacts of switching to LED lighting technology on the prosperity of night-market business owners and operators. The information was gathered in the context of our 2008 market testing field work in Kenya?s Rift Valley Province, which was performed in the towns of Maai Mahiu and Karagita by Arne Jacobson, Kristen Radecsky, Peter Johnstone, Maina Mumbi, and others. Maai Mahiu is a crossroads town; provision of services to travelers and freight carriers is a primary income source for the residents. In contrast, the primary income for Karagita's residents is from work in the large, factory style flower farms on the eastern shores of Lake Naivasha that specialize in producing cut flowers for export to the European market. According to residents, both towns had populations of 6,000 to 8,000 people in June 2008. We focused on quantifying the economics of fuel-based and LED lighting technology in the context of business use by night market vendors and shop keepers. Our research activities with the business owners and operators included baseline measurement of their fuel-based lighting use, an initial survey, offering for sale data logger equipped rechargeable LED lamps, monitoring the adoption of the LED lamps, and a follow-up survey.

  18. Bug repellent safety

    Science.gov (United States)

    ... insect is gone. Alternative Names Insect repellent safety Images Bee sting References Fradin MS. Insect repellents. In: Wolverton SE, ed. Comprehensive Dermatologic Drug Therapy . 3rd ed. Philadelphia, PA: Elsevier Saunders; ...

  19. Lamp-lit bridges as dual light-traps for the night-swarming mayfly, Ephoron virgo: interaction of polarized and unpolarized light pollution.

    Science.gov (United States)

    Szaz, Denes; Horvath, Gabor; Barta, Andras; Robertson, Bruce A; Farkas, Alexandra; Egri, Adam; Tarjanyi, Nikolett; Racz, Gergely; Kriska, Gyorgy

    2015-01-01

    Ecological photopollution created by artificial night lighting can alter animal behavior and lead to population declines and biodiversity loss. Polarized light pollution is a second type of photopollution that triggers water-seeking insects to ovisposit on smooth and dark man-made objects, because they simulate the polarization signatures of natural water bodies. We document a case study of the interaction of these two forms of photopollution by conducting observations and experiments near a lamp-lit bridge over the river Danube that attracts mass swarms of the mayfly Ephoron virgo away from the river to oviposit on the asphalt road of the bridge. Millions of mayflies swarmed near bridge-lights for two weeks. We found these swarms to be composed of 99% adult females performing their upstream compensatory flight and were attracted upward toward unpolarized bridge-lamp light, and away from the horizontally polarized light trail of the river. Imaging polarimetry confirmed that the asphalt surface of the bridge was strongly and horizontally polarized, providing a supernormal ovipositional cue to Ephoron virgo, while other parts of the bridge were poor polarizers of lamplight. Collectively, we confirm that Ephoron virgo is independently attracted to both unpolarized and polarized light sources, that both types of photopollution are being produced at the bridge, and that spatial patterns of swarming and oviposition are consistent with evolved behaviors being triggered maladaptively by these two types of light pollution. We suggest solutions to bridge and lighting design that should prevent or mitigate the impacts of such scenarios in the future. The detrimental impacts of such scenarios may extend beyond Ephoron virgo.

  20. Lamp-lit bridges as dual light-traps for the night-swarming mayfly, Ephoron virgo: interaction of polarized and unpolarized light pollution.

    Directory of Open Access Journals (Sweden)

    Denes Szaz

    Full Text Available Ecological photopollution created by artificial night lighting can alter animal behavior and lead to population declines and biodiversity loss. Polarized light pollution is a second type of photopollution that triggers water-seeking insects to ovisposit on smooth and dark man-made objects, because they simulate the polarization signatures of natural water bodies. We document a case study of the interaction of these two forms of photopollution by conducting observations and experiments near a lamp-lit bridge over the river Danube that attracts mass swarms of the mayfly Ephoron virgo away from the river to oviposit on the asphalt road of the bridge. Millions of mayflies swarmed near bridge-lights for two weeks. We found these swarms to be composed of 99% adult females performing their upstream compensatory flight and were attracted upward toward unpolarized bridge-lamp light, and away from the horizontally polarized light trail of the river. Imaging polarimetry confirmed that the asphalt surface of the bridge was strongly and horizontally polarized, providing a supernormal ovipositional cue to Ephoron virgo, while other parts of the bridge were poor polarizers of lamplight. Collectively, we confirm that Ephoron virgo is independently attracted to both unpolarized and polarized light sources, that both types of photopollution are being produced at the bridge, and that spatial patterns of swarming and oviposition are consistent with evolved behaviors being triggered maladaptively by these two types of light pollution. We suggest solutions to bridge and lighting design that should prevent or mitigate the impacts of such scenarios in the future. The detrimental impacts of such scenarios may extend beyond Ephoron virgo.

  1. A night sky model.

    Science.gov (United States)

    Erpylev, N. P.; Smirnov, M. A.; Bagrov, A. V.

    A night sky model is proposed. It includes different components of light polution, such as solar twilight, moon scattered light, zodiacal light, Milky Way, air glow and artificial light pollution. The model is designed for calculating the efficiency of astronomical installations.

  2. Using DMSP-OLS Night Light Data for Proxying and Comparing Regional Development in Russia and China, 1992-2012

    Science.gov (United States)

    Bennett, M.; Smith, L. C.

    2016-12-01

    To date, no studies have examined the transition from communism to capitalism in Russia or China with night light (NTL) data despite the availability of DMSP-OLS satellite imagery dating back to 1992, one year after the dissolution of the Soviet Union. This paper uses the DMSP-OLS Version 4 stable lights annual image composites for every year from 1992-2012 to reveal the complex and sometimes divergent trajectories of regional development in Russia and China. We first characterize the spatial patterns and characteristics of NTL intensity and extensivity in Russia versus China at national and regional scales across this 21-year period. Although GDP rises in both countries during this time, NTL tells a different story: total night light (tNTL) in Russia in 2012 is slightly lower than in 1992, while tNTL in China is significantly higher. Next, we generate regional-level tNTL from each annual composite and examine their relationships with population, GDP, and fixed capital investment data from the Russian Federal State Statistics Service and the National Bureau of Statistics of China using a fixed effects model. We determine that while the fixed effects "between" model explains more of the differences in tNTL between Russia's federal subjects, the "within" model better explains differences over time within China's provinces. This suggests that on the one hand, Russia's regions are more heterogeneous than China's. On the other hand, whereas change over time in population and GRP explains change over time in tNTL in China's regions, they hardly do so at all for Russia's. Finally, we attempt to combine these socioeconomic variables with NTL data to build an NTL-based typology of regional development, representing a step beyond existing research. The preliminary creation of a regional development typology allows us to begin identifying emerging resource frontiers (places with increases in NTL but decreases in population) along with areas experiencing a reversal of

  3. Towards remote sensing of Arctic ice roads and associated human activities using SUOMI NPP night light images

    Science.gov (United States)

    Bennett, M.; Smith, L. C.; Stephenson, S. R.

    2014-12-01

    Ice roads are often the only cost-effective means of transporting goods and supplies to communities, mines, and other sites in remote parts of the Arctic. Yet, there is no global dataset for Arctic ice roads. However, remotely sensed images from the SUOMI NPP day/night band (DNB) of the Visible Infrared Imaging Radiometer Suite (VIIRS) may allow for the construction of such a dataset. The DNB's high sensitivity to low-level light suggests that while it is not feasible to view ice roads at night per se, other prominent features associated with ice roads can serve as proxies. Using a time series of images taken in winter 2012, 2013, and 2014, SUOMI NPP images are compared with Landsat 8 images and an existing map of the Tibbitt to Contwoyto ice road in the Northwest Territories and Nunavut, Canada. First results reveal that while the ice road's exact path cannot be discerned, key points of human activity along the way can be made out. This bodes well for future applications of DNB imagery to detect ice roads in places like the Russian Federation, for which there is a dearth of publicly available maps. Knowing the location of ice roads is important for two reasons. First, these data can signal sites of natural resource extraction in places for which information is not widely disseminated, such as in the Russian Far East. Second, new geospatial datasets for ice roads can be combined with models assessing impacts of climate change on circumpolar land accessibility (Stephenson et al. 2011) in order to understand where the structural integrity of ice roads may be at risk. As warming temperatures threaten to shorten the season for ice roads, communities and mines alike will need to prepare for changes to their transportation infrastructure, made out of the changing landscape itself.

  4. Night terror

    Science.gov (United States)

    Pavor nocturnus; Sleep terror disorder ... The cause is unknown, but night terrors may be triggered by: Fever Lack of sleep Periods of emotional tension , stress , or conflict Night terrors are most common in children ...

  5. The effect of night illumination, red and infrared light, on locomotor activity, behaviour and melatonin of Senegalese sole (Solea senegalensis) broodstock.

    Science.gov (United States)

    Carazo, I; Norambuena, F; Oliveira, C; Sánchez-Vázquez, F J; Duncan, N J

    2013-06-13

    The present study aimed to determine a non-invasive nocturnal lighting system for the behavioural observation of a highly light sensitive species, Senegalese sole (Solea senegalensis). Locomotor activity, four types of behaviour and plasma melatonin were analysed in groups of 12 adult Senegalese sole (Solea senegalensis) reared in captivity and held under four night illumination treatments: total darkness (control), high 50lux intensity red light (group RH), low 5lux intensity red light (group RL) and infrared light (group IR). All groups experienced the same conditions during the day (lights on from 07:00 to 19:00) with white lighting of 125lux. Clarity of video images taken at night for the observation of fish behaviour were ranked as follows: group RH>RL>IR>control. All treatments presented a daily rhythm in locomotor activity with high activity from 14:00 to 18:00 and low activity from 21:00 to 12:00. The sole exposed to the high intensity red light at night appeared to be disturbed as during the low nocturnal locomotor activity period group RH presented higher activity and significantly higher nocturnal behaviour related to escape or fear than was observed in the other groups. The groups control, RL and IR exhibited similar levels of nocturnal locomotor activity and nocturnal behaviour related to escape or fear. Plasma melatonin, at mid-dark was not significantly different between the control and groups RL and IR, while melatonin was significantly lower in group RH compared to the control. The authors recommended low intensity red night illumination for the non-invasive study of nocturnal behaviour of Senegalese sole adults. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. ANALYZING THE VELOCITY OF URBAN DYNAMIC OVER NORTHEASTERN CHINA USING DMSP-OLS NIGHT-TIME LIGHTS

    Directory of Open Access Journals (Sweden)

    Y. Zhou

    2017-09-01

    Full Text Available Stable night-time lights (NTL data from the Defense Meteorological Satellite Program Operational Line-scan System (DMSPOLS can serve as a good proxy for anthropogenic development. Here DMSP-OLS NTL data was used to detect the urban development status in northeastern China. The spatial and temporal gradients are combined to depict the velocity of urban expanding process. This velocity index represents the instantaneous local velocity along the Earth’s surface needed to maintain constant NTL condition, and has a mean of 0.36 km/yr for northeastern China. The velocity change of NTL is lower in the urban center and its near regions, and the suburbs show a relatively high value. The connecting zones between satellite cities and metropolis have also a rapid rate of NTL evolution. The dynamic process of urbanization over the study area is mainly in a manner of spreading from urban cores to edges. The rank size of the velocity for the prefectures is analyzed and a long tail distribution is found. The velocity index can provide insights for the future pattern of urban sprawl.

  7. Analyzing the Velocity of Urban Dynamic Over Northeastern China Using Dmsp-Ols Night-Time Lights

    Science.gov (United States)

    Zhou, Y.

    2017-09-01

    Stable night-time lights (NTL) data from the Defense Meteorological Satellite Program Operational Line-scan System (DMSPOLS) can serve as a good proxy for anthropogenic development. Here DMSP-OLS NTL data was used to detect the urban development status in northeastern China. The spatial and temporal gradients are combined to depict the velocity of urban expanding process. This velocity index represents the instantaneous local velocity along the Earth's surface needed to maintain constant NTL condition, and has a mean of 0.36 km/yr for northeastern China. The velocity change of NTL is lower in the urban center and its near regions, and the suburbs show a relatively high value. The connecting zones between satellite cities and metropolis have also a rapid rate of NTL evolution. The dynamic process of urbanization over the study area is mainly in a manner of spreading from urban cores to edges. The rank size of the velocity for the prefectures is analyzed and a long tail distribution is found. The velocity index can provide insights for the future pattern of urban sprawl.

  8. Circadian and seasonal responses in Indian weaver bird: subjective interpretation of day and night depends upon both light intensity and contrast between illuminations.

    Science.gov (United States)

    Pandey, Rohit Kumar; Bhardwaj, Sanjay Kumar

    2011-11-01

    This study investigated whether changes in illumination modify perception of day and night conditions in a diurnal species, the Indian weaver bird. Birds were initially subjected to a 12-h light:12-h dark regime (12L:12D; L=20 lux, D =0.5 lux). After every 2 wks, the combinations of light illumination in L and D phases were changed as follows: 20:2 lux, 20:5 lux, 20:10 lux, 20:20 lux, 20:100 lux, and 20:200 lux. Finally, birds were released into dim constant light (0.5 lux) for 2 wks to determine the phase and period of the circadian activity rhythm. They were also laparotomized at periodic intervals to examine the effects of the light regimes on the seasonal testicular cycle. All individuals showed a consistently similar response. As evident by the activity pattern under these light regimes, both in total activity during contrasting light phases and during the 2?h in the beginning and end of first light phase, birds interpreted the period of higher light intensity as day, and the period of lower intensity as the night. During the period of similar light intensity, i.e., under LL, birds free-ran with a circadian period ( ~ 24 h). In bright LL (20 lux), the activity rhythm was less distinct, but periodogram analysis revealed the circadian period for the group as 24.46 (+/-) 0.41 h (mean???SE). However, in dim LL at the end of the experiment, all birds exhibited a circadian pattern with average period of 25.52 (+/-) 0.70 h. All birds also showed testicular growth and regression during the 16-wks study. It is suggested that weaver birds interpret day and night subjectively based on both the light intensity and contrast between illuminations during two phases over the 24 h.

  9. The effects of low levels of light at night upon the endocrine physiology of western scrub-jays (Aphelocoma californica).

    Science.gov (United States)

    Schoech, Stephan J; Bowman, Reed; Hahn, Thomas P; Goymann, Wolfgang; Schwabl, Ingrid; Bridge, Eli S

    2013-11-01

    Florida scrub-jays (Aphelocoma coerulescens) in the suburbs breed earlier than jays in native habitat. Amongst the possible factors that influence this advance (e.g., food availability, microclimate, predator regime, etc.), is exposure to artificial lights at night (LAN). LAN could stimulate the reproductive axis of the suburban jays. Alternatively, LAN could inhibit pineal melatonin (MEL), thus removing its inhibitory influence on the reproductive axis. Because Florida scrub-jays are a threatened species, we used western scrub-jays (Aphelocoma californica) to investigate the effects of LAN upon reproductive hormones and melatonin. Jays were held under conditions in which the dark-phase of the light:dark cycle was without illumination and then under low levels of LAN. Under both conditions, birds were exposed first to short-days (9.5L:14.5D) that were gradually increased to long-days (14.5L:9.5D). At various times, blood samples were collected during the light part of the cycle to measure reproductive hormones (luteinizing hormone, LH; testosterone, T; and estradiol, E2 ). Similarly, samples to assess melatonin were collected during the dark. In males, LAN caused a depression in LH levels and levels were ∼4× greater under long- than short-days. In females, there was no effect of LAN or photoperiod upon LH. LAN resulted in depressed T levels in females, although there was no effect on T in males. E2 levels in both sexes were lower under LAN than under an unlighted dark-phase. Paradoxically, MEL was higher in jays under LAN, and under long-days. MEL did not differ by sex. LAN disrupted the extraordinarily strong correlation between T and E2 that existed under unlighted nocturnal conditions. Overall, our findings fail to support the hypothesis that LAN stimulates the reproductive axis. Rather, the data demonstrate that LAN tends to inhibit reproductive hormone secretion, although not in a consistent fashion between the sexes. © 2013 Wiley Periodicals, Inc.

  10. Emergency/Night Lightning

    Science.gov (United States)

    1980-01-01

    UDEC's highly efficient lighting system is finding wide acceptance among industrial and commercial firms as an energy savings means of providing emergency and night lighting. Originating from Skylab, the system consists of small high frequency fluorescent light fixtures powered by solar cells. Advantages of UDEC's lighting system stem from high reliability and high light output with very low energy drain. Principal components of system are long life fluorescent lamps operated by electronic circuitry, a sealed gelatine cell battery that needs no maintenance for eight years and a solid-state automatic battery charger. Installation of UDEC lighting in a company's six-and-a-half acre warehouse office cut the annual night lighting electric bill from $8,000 a year to $300 per year.

  11. Early life exposure to artificial light at night affects the physiological condition: An experimental study on the ecophysiology of free-living nestling songbirds.

    Science.gov (United States)

    Raap, Thomas; Casasole, Giulia; Pinxten, Rianne; Eens, Marcel

    2016-11-01

    Light pollution or artificial light at night (ALAN) is increasingly recognised to be an important anthropogenic environmental pressure on wildlife, affecting animal behaviour and physiology. Early life experiences are extremely important for the development, physiological status and health of organisms, and as such, early exposure to artificial light may have detrimental consequences for organism fitness. We experimentally manipulated the light environment of free-living great tit nestlings (Parus major), an important model species in evolutionary and environmental research. Haptoglobin (Hp) and nitric oxide (NOx), as important indicators of immunity, health, and physiological condition, were quantified in nestlings at baseline (13 days after hatching) and after a two night exposure to ALAN. We found that ALAN increased Hp and decreased NOx. ALAN may increase stress and oxidative stress and reduce melatonin which could subsequently lead to increased Hp and decreased NOx. Haptoglobin is part of the immune response and mounting an immune response is costly in energy and resources and, trade-offs are likely to occur with other energetically demanding tasks, such as survival or reproduction. Acute inhibition of NOx may have a cascading effect as it also affects other physiological aspects and may negatively affect immunocompetence. The consequences of the observed effects on Hp and NOx remain to be examined. Our study provides experimental field evidence that ALAN affects nestlings' physiology during development and early life exposure to ALAN could therefore have long lasting effects throughout adulthood.

  12. Repellency Awareness Graphic

    Science.gov (United States)

    Companies can apply to use the voluntary new graphic on product labels of skin-applied insect repellents. This graphic is intended to help consumers easily identify the protection time for mosquitoes and ticks and select appropriately.

  13. Field trial of five repellent formulations against mosquitoes in Ahero, Kenya.

    Science.gov (United States)

    Sherwood, Van; Kioko, Elizabeth; Kasili, Sichangi; Ngumbi, Philip; Hollingdale, Michael R

    2009-01-01

    Twelve volunteers, using one leg for repellent application and the other leg as a control, field-tested 5 insect repellent formulations--Avon's (New York, NY) SS220 Spray, SS220 Lotion, and Bayrepel Lotion, and SC Johnson's (Racine, Wisconsin) Autan Bayrepel Lotion--against the standard N,N-diethyl-3-methyl-benzamide (deet) in a rice-growing district near Kisumu, western Kenya, in 2 trials in May and June 2004. In addition to a control leg for each volunteer, an additional control was introduced into the study by the use of a sixth repellent, a "null repellent," which was literally a treatment application of no repellent at all. The 5 active repellent formulations were uniformly applied at the maximum Environmental Protection Agency recommended dose of 1.5 g per 600 cm2 in the first trial and half that dose in the second trial, and none of them failed during the nightly 12-hour test period over 6 consecutive days, May 19 through May 24, 2004, and June 14 through June 19, 2004. However, the repellent control legs demonstrated a statistically significant increased landing rate compared to both the null repellent and the null repellent control leg. This suggests that, in this approach, active repellents increased the capture rate on an adjacent control leg compared to null controls. A single human volunteer can act as his/her own control provided null treatment controls are included.

  14. Out of the Dark: Establishing a Large-Scale Field Experiment to Assess the Effects of Artificial Light at Night on Species and Food Webs

    Directory of Open Access Journals (Sweden)

    Stephanie I. J. Holzhauer

    2015-11-01

    Full Text Available Artificial light at night (ALAN is one of the most obvious hallmarks of human presence in an ecosystem. The rapidly increasing use of artificial light has fundamentally transformed nightscapes throughout most of the globe, although little is known about how ALAN impacts the biodiversity and food webs of illuminated ecosystems. We developed a large-scale experimental infrastructure to study the effects of ALAN on a light-naïve, natural riparian (i.e., terrestrial-aquatic ecosystem. Twelve street lights (20 m apart arranged in three rows parallel to an agricultural drainage ditch were installed on each of two sites located in a grassland ecosystem in northern Germany. A range of biotic, abiotic, and photometric data are collected regularly to study the short- and long-term effects of ALAN on behavior, species interactions, physiology, and species composition of communities. Here we describe the infrastructure setup and data collection methods, and characterize the study area including photometric measurements. None of the measured parameters differed significantly between sites in the period before illumination. Results of one short-term experiment, carried out with one site illuminated and the other acting as a control, demonstrate the attraction of ALAN by the immense and immediate increase of insect catches at the lit street lights. The experimental setup provides a unique platform for carrying out interdisciplinary research on sustainable lighting.

  15. Effects of smartphone use with and without blue light at night in healthy adults: A randomized, double-blind, cross-over, placebo-controlled comparison.

    Science.gov (United States)

    Heo, Jung-Yoon; Kim, Kiwon; Fava, Maurizio; Mischoulon, David; Papakostas, George I; Kim, Min-Ji; Kim, Dong Jun; Chang, Kyung-Ah Judy; Oh, Yunhye; Yu, Bum-Hee; Jeon, Hong Jin

    2017-04-01

    Smartphones deliver light to users through Light Emitting Diode (LED) displays. Blue light is the most potent wavelength for sleep and mood. This study investigated the immediate effects of smartphone blue light LED on humans at night. We investigated changes in serum melatonin levels, cortisol levels, body temperature, and psychiatric measures with a randomized, double-blind, cross-over, placebo-controlled design of two 3-day admissions. Each subject played smartphone games with either conventional LED or suppressed blue light from 7:30 to 10:00PM (150 min). Then, they were readmitted and conducted the same procedure with the other type of smartphone. Serum melatonin levels were measured in 60-min intervals before, during and after use of the smartphones. Serum cortisol levels and body temperature were monitored every 120 min. The Profile of Mood States (POMS), Epworth Sleepiness Scale (ESS), Fatigue Severity Scale (FSS), and auditory and visual Continuous Performance Tests (CPTs) were administered. Among the 22 participants who were each admitted twice, use of blue light smartphones was associated with significantly decreased sleepiness (Cohen's d = 0.49, Z = 43.50, p = 0.04) and confusion-bewilderment (Cohen's d = 0.53, Z = 39.00, p = 0.02), and increased commission error (Cohen's d = -0.59, t = -2.64, p = 0.02). Also, users of blue light smartphones experienced a longer time to reach dim light melatonin onset 50% (2.94 vs. 2.70 h) and had increases in body temperature, serum melatonin levels, and cortisol levels, although these changes were not statistically significant. Use of blue light LED smartphones at night may negatively influence sleep and commission errors, while it may not be enough to lead to significant changes in serum melatonin and cortisol levels. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. A Fat strange Repeller

    Institute of Scientific and Technical Information of China (English)

    申影; 何阅; 姜玉梅; 何大韧

    2004-01-01

    This article reports an observation on a fat strange repeller, which appears after a characteristic crisis observed in a kicked rotor subjected to a piecewise continuous force field. The discontinuity border in the definition range of the two-dimensional mapping, which describes the system, oscillates as the discrete time develops. At a threshold of a control parameter a fat chaotic attractor suddenly transfers to a fat transient set. The strange repeller, which appears after the crisis, is also a fat fractal. This is the reason why super-transience happens

  17. Blue-Enriched White Light Enhances Physiological Arousal But Not Behavioral Performance during Simulated Driving at Early Night

    Science.gov (United States)

    Rodríguez-Morilla, Beatriz; Madrid, Juan A.; Molina, Enrique; Correa, Angel

    2017-01-01

    Vigilance usually deteriorates over prolonged driving at non-optimal times of day. Exposure to blue-enriched light has shown to enhance arousal, leading to behavioral benefits in some cognitive tasks. However, the cognitive effects of long-wavelength light have been less studied and its effects on driving performance remained to be addressed. We tested the effects of a blue-enriched white light (BWL) and a long-wavelength orange light (OL) vs. a control condition of dim light on subjective, physiological and behavioral measures at 21:45 h. Neurobehavioral tests included the Karolinska Sleepiness Scale and subjective mood scale, recording of distal-proximal temperature gradient (DPG, as index of physiological arousal), accuracy in simulated driving and reaction time in the auditory psychomotor vigilance task. The results showed that BWL decreased the DPG (reflecting enhanced arousal), while it did not improve reaction time or driving performance. Instead, blue light produced larger driving errors than OL, while performance in OL was stable along time on task. These data suggest that physiological arousal induced by light does not necessarily imply cognitive improvement. Indeed, excessive arousal might deteriorate accuracy in complex tasks requiring precision, such as driving. PMID:28690558

  18. 夜间交通信号灯视觉传达效果分析与实验%Visual Communication Effect Analysis and Experiment of Traffic Lights at Night

    Institute of Scientific and Technical Information of China (English)

    张媛

    2016-01-01

    传统的视觉表达方法没有考虑夜间雾霾天气带来的影响,降低了交通信号灯视觉传达的效果.为此,提出一种基于双边滤波的增强夜间交通信号灯视觉传达效果的方法.将交通信号灯的RGB空间转换为HSV空间,避免交通信号灯颜色失真的现象;利用双边滤波方法对交通信号灯的亮度进行增强,提高了夜间交通信号灯视觉传达的效果.仿真实验结果表明,改进算法能够增强夜间交通信号灯的亮度和对比度,效果令人满意.%The enhancement effect of the traffic lights at night visual communication is of great importance for maintaining the night traffic order. No night fog weather the impact of the traditional algorithm, which reduces the traffic light visual communication effect. For this, put forward a kind of based on bilateral filter to enhance the effect of traffic lights at night visual communication methods. Traffic lights in the RGB space into HSV space, avoid traffic light color distortion phenomenon; With bilateral filtering method to enhance the brightness of the traffic lights, so as to improve the traffic lights at night the effect of visual communication. The simulation experimental results show that the improved algorithm can enhance the brightness and contrast of traffic lights at night, the effect is satisfactory.

  19. [Effect of genotype and day or night time of testing on mice behavior in the light-dark box and the open-field tests].

    Science.gov (United States)

    Morozova, M V; Kulikov, A V

    2010-01-01

    The light-dark box (LDB) and the open-field (OF) tests are widespread experimental models for studying locomotion and anxiety in laboratory rats and mice. The fact that rodents are nocturnal animals and more active at night raises a critical question of whether behavioral experiments carried out in the light phase are methodologically correct. Parameters of behavior of four mouse strains (C57BL/6J, DBA2/J, AKR/J and CBA/LacJ) in the light-dark box and open-field tests in the light and dark phases were compared. No significant influence of the phase of testing on anxiety in LDB and OF tests was revealed. In the OF test CBA mice showed increased locomotor activity, whereas AKR and C57BL/6 mice showed increased defecation in the dark phase. It was concluded that: 1) the phase of testing is not crucial for the expression of anxiety in LDB and OF; 2) the sensitivity to the phase of testing depends on the genotype; 3) the indices of behavior in the genotypes sensitive to the phase of testing (locomotion in the CBA and defecation in the AKR and C57BL/6 mouse strains) are increased in the dark phase.

  20. Hyperspectral Image-Based Night-Time Vehicle Light Detection Using Spectral Normalization and Distance Mapper for Intelligent Headlight Control

    Directory of Open Access Journals (Sweden)

    Heekang Kim

    2016-07-01

    Full Text Available This paper proposes a vehicle light detection method using a hyperspectral camera instead of a Charge-Coupled Device (CCD or Complementary metal-Oxide-Semiconductor (CMOS camera for adaptive car headlamp control. To apply Intelligent Headlight Control (IHC, the vehicle headlights need to be detected. Headlights are comprised from a variety of lighting sources, such as Light Emitting Diodes (LEDs, High-intensity discharge (HID, and halogen lamps. In addition, rear lamps are made of LED and halogen lamp. This paper refers to the recent research in IHC. Some problems exist in the detection of headlights, such as erroneous detection of street lights or sign lights and the reflection plate of ego-car from CCD or CMOS images. To solve these problems, this study uses hyperspectral images because they have hundreds of bands and provide more information than a CCD or CMOS camera. Recent methods to detect headlights used the Spectral Angle Mapper (SAM, Spectral Correlation Mapper (SCM, and Euclidean Distance Mapper (EDM. The experimental results highlight the feasibility of the proposed method in three types of lights (LED, HID, and halogen.

  1. Rabbit Repellent Paint

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Five gallons of rabbit repellent paint were sent to George Wilson to be applied on the trees of the Tewaukon tree plot. Mr. Wilson requires a 3 or 4 in. brush for...

  2. A low-cost repellent for malaria vectors in the Americas: results of two field trials in Guatemala and Peru

    Directory of Open Access Journals (Sweden)

    Sihuincha Moisés

    2007-08-01

    Full Text Available Abstract Background The cost of mosquito repellents in Latin America has discouraged their wider use among the poor. To address this problem, a low-cost repellent was developed that reduces the level of expensive repellent actives by combining them with inexpensive fixatives that appear to slow repellent evaporation. The chosen actives were a mixture of para-menthane-diol (PMD and lemongrass oil (LG. Methods To test the efficacy of the repellent, field trials were staged in Guatemala and Peru. Repellent efficacy was determined by human-landing catches on volunteers who wore the experimental repellents, control, or 15% DEET. The studies were conducted using a balanced Latin Square design with volunteers, treatments, and locations rotated each night. Results In Guatemala, collections were performed for two hours, commencing three hours after repellent application. The repellent provided >98% protection for five hours after application, with a biting pressure of >100 landings per person/hour. The 15% DEET control provided lower protection at 92% (p 46 landings per person/hour. The 20% DEET control provided significantly lower protection at 64% (p Conclusion In both locations, the PMD/LG repellent provided excellent protection up to six hours after application against a wide range of disease vectors including Anopheles darlingi. The addition of fixatives to the repellent extended its longevity while enhancing efficacy and significantly reducing its cost to malaria-endemic communities.

  3. Combined effects of exposure to dim light at night and fine particulate matter on C3H/HeNHsd mice.

    Science.gov (United States)

    Hogan, Matthew K; Kovalycsik, Taylor; Sun, Qinghua; Rajagopalan, Sanjay; Nelson, Randy J

    2015-11-01

    Air and light pollution contribute to fetal abnormalities, increase prevalence of cancer, metabolic and cardiorespiratory diseases, and central nervous system (CNS) disorders. A component of air pollution, particulate matter, and the phenomenon of dim light at night (dLAN) both result in neuroinflammation, which has been implicated in several CNS disorders. The combinatorial role of these pollutants on health outcomes has not been assessed. Male C3H/HeNHsd mice, with intact melatonin production, were used to model humans exposed to circadian disruption by dLAN and contaminated environmental air. We hypothesized exposure to 2.5 μm of particulate matter (PM2.5) and dLAN (5lx) combines to upregulate neuroinflammatory cytokine expression and alter hippocampal morphology compared to mice exposed to filtered air (FA) and housed under dark nights (LD). We also hypothesized that exposure to PM2.5 and dLAN provokes anxiety-like and depressive-like responses. For four weeks, four groups of mice were simultaneously exposed to ambient concentrated PM2.5 or FA and/or dLAN or LD. Following exposure, mice underwent several behavioral assays and hippocampi were collected for qPCR and morphological analyses. Our results are generally comparable to previous PM2.5 and dLAN reports conducted on mice and implicate PM2.5 and dLAN as potential factors contributing to depression and anxiety. Short-term exposure to PM2.5 and dLAN upregulated neuroinflammatory cytokines and altered CA1 hippocampal structural changes, as well as provoked depressive-like responses (anhedonia). However, combined, PM2.5 and dLAN exposure did not have additive effects, as hypothesized, suggesting a ceiling effect of neuroinflammation may exist in response to multiple pollutants.

  4. Repelling Point Bosons

    Science.gov (United States)

    McGuire, J. B.

    2011-12-01

    There is a body of conventional wisdom that holds that a solvable quantum problem, by virtue of its solvability, is pathological and thus irrelevant. It has been difficult to refute this view owing to the paucity of theoretical constructs and experimental results. Recent experiments involving equivalent ions trapped in a spatial conformation of extreme anisotropic confinement (longitudinal extension tens, hundreds or even thousands of times transverse extension) have modified the view of relevancy, and it is now possible to consider systems previously thought pathological, in particular point Bosons that repel in one dimension. It has been difficult for the experimentalists to utilize existing theory, mainly due to long-standing theoretical misunderstanding of the relevance of the permutation group, in particular the non-commutativity of translations (periodicity) and transpositions (permutation). This misunderstanding is most easily rectified in the case of repelling Bosons.

  5. FAQ: Insect Repellent Use and Safety

    Science.gov (United States)

    ... Mosquito Surveillance Software Health Education Public Service Videos Insect Repellent Use & Safety Recommend on Facebook Tweet Share ... the repellent with you. Top of Page Can insect repellents be used on children? Yes. Most products ...

  6. 微光夜视仪消热化结构设计%Refrigeratory structural design of Low-light level night vision device

    Institute of Scientific and Technical Information of China (English)

    张博

    2012-01-01

    Low-light level night vision device including two parts: one is optical systems,the objective and the eyepiece ;the other is image intensifier, photoelectric converter. Refrigeratory is designing Optical Elements.the structure form optical system to eliminate the influence of the temperature, promise thus the optical function of instrument stabilizes of process.%微光夜视仪结构主要由两部分组成:一部分是光学系统,包括目镜和物镜;另一部分是像增强器,即光电转换放大部分,包括像增强器及其必须的高压电源。消热化是指通过设计光学零件、光学系统结构来补偿温度的变化,从而保证仪器光学性能稳定的过程。

  7. Night Terrors (For Parents)

    Science.gov (United States)

    ... Kids to Be Smart About Social Media Night Terrors KidsHealth > For Parents > Night Terrors Print A A A en español Terrores nocturnos What Are Night Terrors? Most parents have comforted their child after the ...

  8. Science Night

    CERN Document Server

    2004-01-01

    Would it surprise you to know that you can measure the speed of light using chocolate and a microwave oven? If you're interested in this and in finding out much more, come along to the Museum of the History of Science on 3 and 4 July 2004, when dozens of companies, institutions, colleges and organizations will be running exhibits, shows, and displays on the theme of counting and measuring. CERN will be there with a display stand that includes two particle detectors. Full details are available from the Museum website at: http://www.lanuitdelascience.ch/

  9. Sharks senses and shark repellents.

    Science.gov (United States)

    Hart, Nathan S; Collin, Shaun P

    2015-01-01

    Despite over 70 years of research on shark repellents, few practical and reliable solutions to prevent shark attacks on humans or reduce shark bycatch and depredation in commercial fisheries have been developed. In large part, this deficiency stems from a lack of fundamental knowledge of the sensory cues that drive predatory behavior in sharks. However, the widespread use of shark repellents is also hampered by the physical constraints and technical or logistical difficulties of deploying substances or devices in an open-water marine environment to prevent an unpredictable interaction with a complex animal. Here, we summarize the key attributes of the various sensory systems of sharks and highlight residual knowledge gaps that are relevant to the development of effective shark repellents. We also review the most recent advances in shark repellent technology within the broader historical context of research on shark repellents and shark sensory systems. We conclude with suggestions for future research that may enhance the efficacy of shark repellent devices, in particular, the continued need for basic research on shark sensory biology and the use of a multi-sensory approach when developing or deploying shark repellent technology.

  10. A night with good vibrations

    CERN Multimedia

    2002-01-01

    For its third edition, the Museum d'histoire des sciences invites you to a Science Night under the banner of waves and undulations. Scientists, artists and storytellers from more than forty institutes and local or regional associations will show in only one weekend that waves and undulations form an integral part of our daily environment. Telephones, televisions, radios, irons, lighting, music, sun rays, stars, rainbows, earthquakes and other natural phenomena - all produce, emit or receive waves or undulations. The visitors attending the Night will be able to get in contact with the nature of waves through interactive exhibitions on sound and light and through hands-on demonstrations arranged around the Bartholoni villa and in the Park of the Perle du lac. An amusing and distracting way to familiarize yourself with the concepts of wavelength, frequency and interference lengths... In addition to the stands, the Night will offer many other activities: reconstructions of critical experiments, scientific consu...

  11. A night with good vibrations

    CERN Document Server

    2002-01-01

    Next week-end, the Geneva Science History Museum invites you to a Science Night under the banner of waves and vibrations. Scientists, artists and storytellers from more than forty institutes and local or regional associations will show that waves and vibrations form an integral part of our environment. You will be able to get in contact with the nature of waves through interactive exhibitions on sound and light and through hands-on demonstrations arranged in the Park of the Perle du Lac. On the CERN stand, you will be able to measure the speed of light with a bar of chocolate, and understand the scattering of waves with plastic ducks. Amazing, no? In addition to the stands, the Night will offer many other activities: reconstructions of experiments, a play, a concert of crystal glasses, an illuminated fountain, a house of spirits. More information Science Night, 6 and 7 July, Park of the Perle du Lac, Geneva

  12. From wealth to health: modelling the distribution of income per capita at the sub-national level using night-time light imagery

    Directory of Open Access Journals (Sweden)

    Tandon Ajay

    2005-02-01

    Full Text Available Abstract Background Sub-national figures providing information about the wealth of the population are useful in defining the spatial distribution of both economic activity and poverty within any given country. Furthermore, since several health indicators such as life expectancy are highly correlated with household welfare, sub-national figures allow for the estimation of the distribution of these health indicators within countries when direct measurement is difficult. We have developed methods that utilize spatially distributed information, including night-time light imagery and population to model the distribution of income per capita, as a proxy for wealth, at the country and sub-national level to support the estimation of the distribution of correlated health indicators. Results A first set of analysis are performed in order to propose a new global model for the prediction of income per capita at the country level. A second set of analysis is then confirming the possibility to transfer the country level approach to the sub-national level on a country by country basis before underlining the difficulties to create a global or regional models for the extrapolation of sub-national figures when no country data set exists. Conclusions The methods described provide promising results for the extrapolation of national and sub-national income per capita figures. These results are then discussed in order to evaluate if the proposed methods could not represent an alternative approach for the generation of consistent country specific and/or global poverty maps disaggregated to some sub-national level.

  13. Application of light curing silica sol in water repellence finish of cotton fabric%光固化SiO2溶胶在棉织物拒水整理中的应用

    Institute of Scientific and Technical Information of China (English)

    田太洲; 闵洁; 徐进进; 蔡丹

    2015-01-01

    The light curing silica sol was prepared by sol- gel technology using tetraethylorthosilicate (TEOS) and 3- azidopropyltriethoxysilane as precursor, ammonia as catalyst, which was applied in water repel⁃lence on cotton fabrics with hydrophobic additives hexadecyltrimethoxysilane (HDTMS) as additive. The water repel ence property of fabric was endowed by dip- padding the light curing silica sol, then dipping into alkane siloxane, and then was exposed to UV light without curing. The treated cotton fabrics were characterized by scanning electron microscopy (SEM) and X- ray photoelectron spectroscopy (XPS). The results showed that the light curing silica sol nanoparticles were coated on the cotton fiber surface and increased the surface roughness. Contact angle results demonstrated that the water contact angle of the treated cotton fabric was 155° for 5μL and was stil greater than 135° after 30 times soaping.%利用溶胶-凝胶技术,以正硅酸四乙酯、3-叠氮丙基三乙氧基硅烷为前驱体,氨水为催化剂制备光固化二氧化硅溶胶,以十六烷基三甲氧基硅烷为拒水剂对棉织物进行拒水整理。先浸轧光固化二氧化硅溶胶,再浸渍烷烃硅氧烷,无需焙烘,通过紫外光照直接赋予织物拒水性能。采用扫描电镜、X射线光电子能谱仪对整理后的棉织物进行测试。结果表明,光固化二氧化硅溶胶沉积在织物表面,提高了棉织物的粗糙度。接触角测试表明,棉织物对水接触角(5μL)达到155°;整理后的棉织物经30次皂洗后,与水的接触角仍大于135°。

  14. [Prevention with repellent in children].

    Science.gov (United States)

    Sorge, F

    2009-10-01

    Use of topical insect repellent is an important component in prophylaxis of arthropod bite vector borne diseases. Topical insect repellent are used in a three part management regimen, along with impregnated clothing and mosquito netting. Parental training for efficacious and secure use of repellents for their children is essential part of a successful strategy to combat Lyme borreliosis, dengue fever, Chikungunya, West Nile virus infection and malaria, amongst children, according to local epidemiological risks. Rational repellent prescription for a child must take into account age, active substance concentration, topical substance tolerance, nature and surface of the skin to protect, number of daily applications, and the length of use in a benefit-risk ratio assessment perspective. The 4 currently repellents recommended by Whopes (Who) for their long lasting efficacy and patient tolerance are: 1) Citriodiol (PMD), 2) DEET, 3) Icaridine (KB3023), and 4) IR3535. In field trials the minimum required concentration of each four of these agents to be effective for 3 hours against most arthropods is 20% (in cream, roll-on or spray vehicle). Described side effects of these agents are mild, being limited to local irritative dermatitis and allergy. The risk of severe side effects has been related to DEET misused and neurotoxicity. The international recommendations concerning utilization of topical repellent amongst children for prophylaxis of arthropod borne diseases is concerning short term usage (several weeks). But the use of repellent is sub chronic or chronic amongst the majority of children living in subtropical regions where these vector borne diseases are endemic. And toxicity of topical repellent when used sub-chronically and chronically is not well studied in pediatric age groups. Taking into account these considerations, the current recommendations of the French Group of Tropical Paediatrics are to teach the parents of children who live in arthropod vector disease

  15. Repellents Against Land Leeches for Military Use

    Directory of Open Access Journals (Sweden)

    T. Koshy

    1967-05-01

    Full Text Available A short account of the habits and nature of depredations of the leeches in the Himalayan region is given. The requirements for a leech repellent, to be of use in a hot humid and rainy area are stressed. A brief survey of the repellents and the need for their suitable screening for use in this area is made. Mention is made of some newer insect and mite repellents, which are likely to prove leech repellents as well.It is suggested that emphasis should be made on the choice of a impregnated repellent for military use in the area rather than on a 'skin repellent.

  16. Vision - night blindness

    Science.gov (United States)

    ... People with night blindness often have trouble seeing stars on a clear night or walking through a ... certain drugs Vitamin A deficiency (rare) Nontreatable causes: Birth defects Retinitis pigmentosa

  17. Sleep Terrors (Night Terrors)

    Science.gov (United States)

    Sleep terrors (night terrors) Overview By Mayo Clinic Staff Sleep terrors are episodes of screaming, intense fear and flailing while still asleep. Also known as night terrors, sleep terrors often are paired with sleepwalking. Like ...

  18. Effects of the spatial repellent metofluthrin on landing rates of outdoor biting anophelines in Cambodia, Southeast Asia.

    Science.gov (United States)

    Charlwood, J D; Nenhep, S; Protopopoff, N; Sovannaroth, S; Morgan, J C; Hemingway, J

    2016-06-01

    The emergence of artemisinin-resistant malaria in Southeast Asia is a major problem. The fact that many people become infected with malaria when they are outside has prompted the development of 'spatial' rather than topical repellents. The respective effects of one or four slow-release emanators of metofluthrin, a pyrethroid, were tested in Pailin, Pursat and Koh Kong, Cambodia. Numbers of mosquitoes counted in outdoor landing catches when one or four emanators were suspended close to the collector were compared with control collections. In Pailin, the effects of emanators on catches in Furvela tent traps and Centers for Disease Control (CDC) light traps suspended underneath houses were also investigated. Rate ratios were used to determine differences. A total of 29 255 mosquitoes were collected over 2934 h of landing collections, 87 nights of tent trapping and 81 nights of light trap capture. In Pailin, landing rates were reduced by 48% by a single emanator and by 67% by four emanators (P metofluthrin collections (P > 0.05). These findings suggest that although the product can produce a significant effect, it requires further improvement. © 2016 The Royal Entomological Society.

  19. Family Reading Night

    Science.gov (United States)

    Hutchins, Darcy; Greenfeld, Marsha; Epstein, Joyce

    2007-01-01

    This book offers clear and practical guidelines to help engage families in student success. It shows families how to conduct a successful Family Reading Night at their school. Family Night themes include Scary Stories, Books We Love, Reading Olympics, Dr. Seuss, and other themes. Family reading nights invite parents to come to school with their…

  20. Durable Dust Repellent Coating for Metals Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Durable Dust Repellent Coating (DDRC) consists of nano-phase silica, titania, or other oxide coatings to repel dust in a vacuum environment over a wide range of...

  1. The effect of high frequency sound on Culicoides numbers collected with suction light traps

    Directory of Open Access Journals (Sweden)

    Gert J. Venter

    2012-04-01

    Full Text Available Culicoides midges (Diptera: Ceratopogonidae, are involved in the transmission of various pathogens that cause important diseases of livestock worldwide. The use of insect repellents to reduce the attack rate of these insects on livestock could play an important role as part of an integrated control programme against diseases transmitted by these midges. The objective of this study was to determine whether high frequency sound has any repellent effect on Culicoides midges. The number of midges collected with 220 V Onderstepoort white light traps fitted with electronic mosquito repellents (EMRs, emitting 5-20 KHz multi-frequency sound waves, was compared with that of two untreated traps. Treatments were rotated in two replicates of a 4 x 4 randomised Latin square design. Although fewer midges were collected in the two traps fitted with EMRs, the average number collected over eight consecutive nights was not significantly different. The EMRs also had no influence on any of the physiological groups of Culicoides imicola Kieffer or the species composition of the Culicoides population as determined with light traps. The results indicate that high frequency sound has no repellent effect on Culicoides midges. There is therefore no evidence to support their promotion or use in the protection of animals against pathogens transmitted by Culicoides midges.

  2. Evaluation of botanicals as repellents against mosquitoes.

    Science.gov (United States)

    Das, N G; Baruah, I; Talukdar, P K; Das, S C

    2003-01-01

    Repellent properties of three plant extracts--essential oil (steam distillate) of Zanthoxylum limonella (fruits), Citrus aurantifolia (leaf) and petroleum ether extract of Z. limonella (fruits) were evaluated as repellent against Aedes (S.) albopictus mosquitoes in mustard (Dhara) and coconut (Parachute) oil base under laboratory conditions. Three concentrations--10, 20 and 30% of the repellents were evaluated. Repellents in mustard oil afforded longer protection time against the bites of Aedes (S.) albopictus mosquitoes than those in coconut oil. At 30% concentration, 296-304 min protection time was achieved by the test repellents in mustard oil base while repellents in coconut oil exhibited 223.5-245 min protection time at the same concentration. Oil of Z. limonella gave the highest protection time against the bites of Aedes (S.) albopictus mosquitoes at all the concentrations than other herbal repellents tested both in mustard and coconut oil.

  3. From Chemistry to Behavior. Molecular Structure and Bioactivity of Repellents against Ixodes ricinus Ticks.

    Directory of Open Access Journals (Sweden)

    Simone Del Fabbro

    Full Text Available Tick-borne zoonoses are considered as emerging diseases. Tick repellents represent an effective tool for reducing the risk of tick bite and pathogens transmission. Previous work demonstrated the repellent activity of the phenylpropanoid eugenol against Ixodes ricinus; here we investigate the relationship between molecular structure and repellency in a group of substances related to that compound. We report the biological activity of 18 compounds varying for the presence/number of several moieties, including hydroxyl and methoxy groups and carbon side-chain. Each compound was tested at different doses with a bioassay designed to measure repellency against individual tick nymphs. Both vapor pressure and chemical features of the tested compounds appeared to be related to repellency. In particular, the hydroxyl and methoxy groups as well as the side-chain on the benzene ring seem to play a role. These results are discussed in light of available data on chemical perception in ticks. In the course of the study new repellent compounds were identified; the biological activity of some of them (at least as effective as the "gold standard" repellent DEET appears to be very promising from a practical point of view.

  4. "Starry Night" on Computer.

    Science.gov (United States)

    Freifeld, Susan

    1998-01-01

    Discusses an exploration of depth in landscape painting using Vincent van Gogh's "Starry Night" as an example. Used computer drawing software for children to allow students to create their own interpretations of "Starry Night" while exploring means of portraying depth in two-dimensional art. (DSK)

  5. Synthesized night vision goggle

    Science.gov (United States)

    Zhou, Haixian

    2000-06-01

    A Synthesized Night Vision Goggle that will be described int his paper is a new type of night vision goggle with multiple functions. It consists of three parts: main observing system, picture--superimposed system (or Cathode Ray Tube system) and Charge-Coupled Device system.

  6. Evaluation of botanicals as repellents against mosquitoes

    Directory of Open Access Journals (Sweden)

    N.G. Das, I. Baruah, P.K. Talukdar & S.C. Das

    2003-03-01

    Full Text Available Repellent properties of three plant extracts—essential oil (steam distillate of Zanthoxylumlimonella (fruits, Citrus aurantifolia (leaf and petroleum ether extract of Z. limonella (fruitswere evaluated as repellent against Aedes (S. albopictus mosquitoes in mustard (Dhara and coconut(Parachute oil base under laboratory conditions. Three concentrations—10, 20 and 30% of therepellents were evaluated. Repellents in mustard oil afforded longer protection time against thebites of Aedes (S. albopictus mosquitoes than those in coconut oil. At 30% concentration, 296–304 min protection time was achieved by the test repellents in mustard oil base while repellents incoconut oil exhibited 223.5–245 min protection time at the same concentration. Oil of Z. limonellagave the highest protection time against the bites of Aedes (S. albopictus mosquitoes at all theconcentrations than other herbal repellents tested both in mustard and coconut oil.

  7. Insect Repellent Properties of Melaleuca alternifolia

    OpenAIRE

    Mohamad Adib Bin Edris; Awang Soh Yusuff Mamat; Muhammad Shahzad Aslam; Muhammad Syarhabil Ahmad

    2016-01-01

    The aim of this study is to compare the use of plant-based insect repellents that are environment friendly with the use of insect repellents based on chemical substances which can be harmful to the environment and human health. The plant studied here is "tea tree"; its scientific name is Melaleuca alternifolia. Essential oil from this plant is extracted by steam distillation method. Based on the previous research, tea tree oil has antimicrobial, antifungal, anti-inflammatory, and insect repel...

  8. Rodent-repellent studies. I. Method for the evaluation of chemical repellents

    Science.gov (United States)

    Bellack, E.; DeWitt, J.B.

    1949-01-01

    A biological assay procedure and a method for the numerical expression of results have been devised for the determination of the repellency to rodents of different chemical compounds. The procedure is based upon the degree of acceptability of foods containing the candidate repellents,. and has been shown. to offer a rapid, reliable measure of repellent activIty.

  9. Repellent Action of Neem (Azadirachta indica) Seed Oil Cream ...

    African Journals Online (AJOL)

    Nekky Umera

    potential of neem seed oil cream as mosquito repellent particularly at higher ... In the present study, neem Seed oil extracted from Azadirachta indica plant .... repellency was in two phases, first to determine the repellency properties of.

  10. The relationship between obesity and exposure to light at night: cross-sectional analyses of over 100,000 women in the Breakthrough Generations Study

    National Research Council Canada - National Science Library

    McFadden, Emily; Jones, Michael E; Schoemaker, Minouk J; Ashworth, Alan; Swerdlow, Anthony J

    2014-01-01

    There has been a worldwide epidemic of obesity in recent decades. In animal studies, there is convincing evidence that light exposure causes weight gain, even when calorie intake and physical activity are held constant...

  11. The Starry Night.

    Science.gov (United States)

    Hausman, Jerome J.

    1985-01-01

    Vincent Van Gogh's painting "The Starry Night" is discussed, and ways that an art teacher can use this painting as a resource for learning are suggested. Specific activities to use with elementary and secondary students are included. (RM)

  12. Urinating more at night

    Science.gov (United States)

    ... calcium level Certain medicines, including water pills (diuretics) Diabetes insipidus Waking often during the night to urinate can ... medicines are you taking? Have you changed your diet? Do you drink caffeine and alcohol? If so, ...

  13. Night Eating Disorders

    OpenAIRE

    Deniz Tuncel; Fatma Özlem Orhan

    2009-01-01

    Hunger is an awakening related biological impulse. The relationship between hunger and sleep is moderated by the control of homeostatic and circadian rhytms of the body. Abnormal eating behavior during sleep period could result from different causes. Abnormal eating during the main sleep period has been categorized as either night eating syndrome or sleep related eating disorder. Night eating syndrome (NES) is an eating disorder characterised by the clinical features of morning anorexia, even...

  14. History of the Night

    CERN Document Server

    CERN. Geneva

    2016-01-01

    The definition of the night, as the period between sunset and sunrise, is consistent and unalterable, regardless of culture and time. However the perception of the night and its economic, social, and cultural roles are subject to change. Which parameters determine these changes? What can we learn by studying them about the specific character of a culture? Why do people experience the night in different ways in different historical periods and how did this affect their lives? How do references to nocturnal activities in historical sources (works of art, narratives) reveal what the artists/authors wish to communicate to their audiences? Can the night be a meaningful subject of historical and archaeological enquiry? A study of the source material in the Greek world (ca. 400 BC-ca. AD 400) shows a continuous effort to colonize the night with activities of the day, to make the night safer, more productive, more rational, more efficient. The main motors for this change were social developments and religion, no...

  15. 明暗对峙的绝望抗争--论夏目漱石作品《梦十夜》之“第九夜”%Desperate Struggle in the Confrontation of Light and Darkness:On Natsume Souseki's The Ninth Night of Ten Nights of Dreams

    Institute of Scientific and Technical Information of China (English)

    张青

    2014-01-01

    夏目漱石的《梦十夜》以梦幻的形式揭示了潜在人类灵魂深处的“原罪”意识、对生的困惑与不安、以及在绝望中的抗争,其中“第九夜”特别凸显这一主题。以“第九夜”为中心,通过分析母子对话,揭示一个母亲的“心像世界”。在“第九夜”中,我们从一种看似“徒劳”的反抗中感悟到:现实虽然是一个非理性的、令人绝望的社会,但同时也是一个蕴含希望的混沌世界,如果能从“徒劳”行为中发现蕴含的人生意义,就能够使隐遁在黑暗中的希望之光发生戏剧化的逆转,显现出“徒劳”转为“幸福”的端倪。%In the form of dreams,Natsume Souseki’s Ten Nights of Dreams reveaLs the consciousness of the“originaL sin”deep down in human souLs and the confusion and insecurity of mankind about Life,of which“the ninth night”is the highLight of this theme. Focusing on“the ninth night”,and by anaLyzing the“image of the inner worLd”of the mother carrying her chiLd,this paper reveaLs the theme shared in Ten Nights of Dreams,which is“desperate struggLe”in the confrontation of Light and darkness. The anaLysis shows that through struggLes against fate that seem in vain,we reaLize the worLd is mixed with irrationaLity,despair,and at the same time,great hope. Or,if we can not find the meaning of Life hidden in the Sisyphean efforts de-scribed by ALbert Camus,there can never be a dramatic reversaL of the disappearing Light of hope,which marks the beginning of bLessedness out of Sisyphean efforts.

  16. 公园夜景观照明设计——以浙江省苍南县工业园区湿地公园为例%Lighting design of the night landscape in the park——To take wetland park in industrial parks of Cangnan county Zhejiang province for an example

    Institute of Scientific and Technical Information of China (English)

    张加友

    2012-01-01

    Night landscape is a combination of lighting science and art.This paper elaborated the design principles of the night landscape lighting,and proposes the design concept of photopia vision lighting,such as plaza,parking areas,and the design concept of decorative landscape,such as trail,plant,water body,building and rest area,in order to build the unique night landscape in park.%夜景观是照明科学与艺术的有机结合,该文在阐述公园夜景观照明设计原则基础上,以苍南工业园区湿地公园为例,提出广场、停车场等明视照明和游步道、植物、水体、建筑、休息场所等饰景照明设计构思。

  17. Multi-channel automotive night vision system

    Science.gov (United States)

    Lu, Gang; Wang, Li-jun; Zhang, Yi

    2013-09-01

    A four-channel automotive night vision system is designed and developed .It is consist of the four active near-infrared cameras and an Mulit-channel image processing display unit,cameras were placed in the automobile front, left, right and rear of the system .The system uses near-infrared laser light source,the laser light beam is collimated, the light source contains a thermoelectric cooler (TEC),It can be synchronized with the camera focusing, also has an automatic light intensity adjustment, and thus can ensure the image quality. The principle of composition of the system is description in detail,on this basis, beam collimation,the LD driving and LD temperature control of near-infrared laser light source,four-channel image processing display are discussed.The system can be used in driver assistance, car BLIS, car parking assist system and car alarm system in day and night.

  18. Chapter 12: spatial or area repellents

    Science.gov (United States)

    Spatial repellents a three-dimensional zone of protection around a host from attacks by biting arthropods. This chapter reviews current knowledge and outlines future directions for utilization of spatial repellents. Current knowledge includes the kinds of products, both active and passive devices,...

  19. Structural optimization of super-repellent surfaces

    DEFF Research Database (Denmark)

    Cavalli, Andrea; Bøggild, Peter; Okkels, Fridolin

    2013-01-01

    Micro-patterning is an effective way to achieve surfaces with extreme liquid repellency. This technique does not rely on chemical coatings and is therefore a promising concept for application in food processing and bio-compatibile coatings. This super-repellent behaviour is obtained by suspending...

  20. Novel Carboxamides as Potential Mosquito Repellents

    Science.gov (United States)

    2010-09-01

    deet) is themost ef- fective andbest-studied arthropod repellent currently on the market . However, it does not provide a long duration of protection...Gaudin, J. M., T. Lander, and O. Nikolaenko. 2008. Carbox- amides combining favorable olfactory properties with insect repellency. Chem. Biodivers. 5

  1. Eliminating animal facility light-at-night contamination and its effect on circadian regulation of rodent physiology, tumor growth, and metabolism: a challenge in the relocation of a cancer research laboratory.

    Science.gov (United States)

    Dauchy, Robert T; Dupepe, Lynell M; Ooms, Tara G; Dauchy, Erin M; Hill, Cody R; Mao, Lulu; Belancio, Victoria P; Slakey, Lauren M; Hill, Steven M; Blask, David E

    2011-05-01

    Appropriate laboratory animal facility lighting and lighting protocols are essential for maintaining the health and wellbeing of laboratory animals and ensuring the credible outcome of scientific investigations. Our recent experience in relocating to a new laboratory facility illustrates the importance of these considerations. Previous studies in our laboratory demonstrated that animal room contamination with light-at-night (LAN) of as little as 0.2 lx at rodent eye level during an otherwise normal dark-phase disrupted host circadian rhythms and stimulated the metabolism and proliferation of human cancer xenografts in rats. Here we examined how simple improvements in facility design at our new location completely eliminated dark-phase LAN contamination and restored normal circadian rhythms in nontumor-bearing rats and normal tumor metabolism and growth in host rats bearing tissue-isolated MCF7(SR(-)) human breast tumor xenografts or 7288CTC rodent hepatomas. Reducing LAN contamination in the animal quarters from 24.5 ± 2.5 lx to nondetectable levels (complete darkness) restored normal circadian regulation of rodent arterial blood melatonin, glucose, total fatty and linoleic acid concentrations, tumor uptake of O(2), glucose, total fatty acid and CO(2) production and tumor levels of cAMP, triglycerides, free fatty acids, phospholipids, and cholesterol esters, as well as extracellular-signal-regulated kinase, mitogen-activated protein kinase, serine-threonine protein kinase, glycogen synthase kinase 3β, γ-histone 2AX, and proliferating cell nuclear antigen.

  2. A Midsummer Night's Science

    CERN Document Server

    2001-01-01

    Last year, the first Science Night attracted nearly 1500 people. Dipping into history for the space of one night? This is the idea of Geneva's Museum of the History of Science, which is organizing its second Science Night, on 7 and 8 July, on the history of science. The first such event, held last year, was a considerable success with almost 15 000 visitors. The second Science Night, to be held in the magnificent setting of the Perle du Lac Park in Geneva, promises to be a winner too. By making science retell its own history, this major event is intended to show how every scientific and technical breakthrough is the culmination of a long period of growth that began hundreds of years in the past. Dozens of activities and events are included in this programme of time travel: visitors can study the night sky through telescopes and see what Galileo first observed, and then go to see a play on the life of the Italian scientist. Another play, commissioned specially for the occasion, will honour Geneva botanist De ...

  3. Preliminary study on mosquito repellent and mosquitocidal activities of Ocimum gratissimum (L.) grown in eastern Nigeria.

    Science.gov (United States)

    Oparaocha, Evangeline T; Iwu, Iraneus; Ahanakuc, J E

    2010-03-01

    The study examined the mosquito-repellent and mosquitocidal activities of the volatile oil of Ocimum gratissimum at three different locations (World Bank Estate, Ihitte and Umuekunne) in Imo State, eastern Nigeria, with the purpose of sourcing for mosquito repellent that is cheap, abundant, environment and user-friendly. Four different lotions; 20% (v/v) and 30% (v/v) concentrations each of the extracted volatile oil in two natural oil bases (olive and palm kernel) were made and six volunteered human baits were used to evaluate the mosquito repellent and mosquitocidal activities of the stock materials at the three different centres from September to November 2008. Topical application of each of the four different lotions significantly (p mosquitoes in all the three locations tested. The 30% (v/v) concentration in olive oil base exhibiting highest average percentage repellencies of 97.2, 95.7 and 96.3% at World Bank Estate, Ihitte and Umuekunne centres respectively while the 20% (v/v) concentration in palm kernel oil base had the least repellency of 36.3, 41.6 and 36.3%, respectively. The other two formulations had values ranging from 67.8 to 80% in the three locations. The 30% (v/v) concentration in both olive and palm kernel oil bases afforded all night protection against mosquito bites in all the centres, and demonstrated fast knockdown and paralyzing effect on few mosquitoes at the urban centre (World Bank Estate). The study confirms that O. gratissimum grown in eastern Nigeria has mosquito-repellent and mosquitocidal potentials and the formulations could be used to reduce human-mosquito contacts and hence mosquito-borne diseases and irritations caused by their bites.

  4. A community-wide study of malaria reduction: evaluating efficacy and user-acceptance of a low-cost repellent in northern Ghana.

    Science.gov (United States)

    Dadzie, Samuel; Boakye, Daniel; Asoala, Victor; Koram, Kwadwo; Kiszewski, Anthony; Appawu, Maxwell

    2013-02-01

    NO MAS (NM) mosquito repellent was evaluated in two farming villages (4 km apart) in the Kassena Nankana district of northern Ghana. We determined its efficacy against local malaria vectors, degree of user acceptance, and its effect on malaria prevalence in households using insecticide-treated bed nets. The average protective efficacy of NM against Anopheles mosquitoes over 9 hours was 89.6%. Controls averaged 86 bites/person/night versus 9 bites/person/night with the use of NM. Use of repellent was associated with a decrease of absolute malaria prevalence by 19.2% in the repellent village and by 6.5% in the control village (45.5 to 26.3, and 29.5 to 23.0, respectively). The user-acceptance rate of NM repellent was 96.1%. Ten percent (10%) of repellent users reported irritation as the main adverse effect during the period. Eighty-five percent (85%) of the users found the odor of NM appealing and 87% reported no inconvenience in applying the repellent daily.

  5. Durability of two water repelents applied to granite

    Directory of Open Access Journals (Sweden)

    Rivas, T.

    1998-06-01

    Full Text Available The durability of two water-repellents for granitic stonework was determined. Weathered and sound samples of granites widely used in building construction and restoration in Galicia (NW Spain were treated with water repellents of known efficacy, and then subjected to two artificial weathering tests: prolonged exposure to UV light, and sodium sulphate crystallization cycles. In both tests, but especially in the salt crystallization cycles, both treatments rapidly lost their water-repellency. Furthermore, the hydrophobic layer of water repellent impeded salt mobility, favouring fissuration parallel to the treated surface, which was eventually shed in the form of a plaque.

    Se presentan los resultados de la durabilidad de dos tratamientos de hidrofugación aplicados a rocas graníticas ampliamente utilizados en la construcción de edificios en Galicia (Noroeste de España. Tras la evaluación de la eficacia de dichos tratamientos, cuyos resultados se presentaron en un trabajo anterior, se someten las muestras tratadas a dos ensayos diferentes de envejecimiento acelerado: ciclos de exposición a la luz ultravioleta y ciclos de cristalización de sulfato de sodio. Los productos hidrofugantes muestran una escasa resistencia a ambos ensayos, sobre todo a los ciclos de cristalización de sulfato de sodio; esta débil durabilidad se manifiesta en una rápida pérdida de sus propiedades hidrofugantes. Así mismo, se observa que la presencia de la capa hidrófoba en la piedra funciona como una barrera frente a la movilidad de sales, lo que ocasiona el total desprendimiento de aquella y un fuerte deterioro del material rocoso.

  6. Insect Repellent Properties of Melaleuca alternifolia

    Directory of Open Access Journals (Sweden)

    Mohamad Adib Bin Edris

    2016-08-01

    Full Text Available The aim of this study is to compare the use of plant-based insect repellents that are environment friendly with the use of insect repellents based on chemical substances which can be harmful to the environment and human health. The plant studied here is "tea tree"; its scientific name is Melaleuca alternifolia. Essential oil from this plant is extracted by steam distillation method. Based on the previous research, tea tree oil has antimicrobial, antifungal, anti-inflammatory, and insect repellent properties. Some experiments were done on tea tree oil to determine its insect repellent properties and the suitable concentration that can be used to make sure its repelling effect is optimum. The purpose of this determination is to avoid its harmful effect on humans because it can be toxic if it is used at high concentration. The results showed that tea tree oil repelled Tribolium castaneum. Furthermore, the toxicity assays also gave positive result where the tea tree oil has toxic properties against Solenopsis invicta. The lethal dose (LD of tea tree oil to kill 50% of a group of S. invicta is 23.52 µL/mL. This LD50 is determined by using the arithmetic method of Karber. Broadly, the results showed that M. alternifolia has insect repellent properties and shows toxicity against certain insects.

  7. Night Eating Disorders

    Directory of Open Access Journals (Sweden)

    Deniz Tuncel

    2009-08-01

    Full Text Available Hunger is an awakening related biological impulse. The relationship between hunger and sleep is moderated by the control of homeostatic and circadian rhytms of the body. Abnormal eating behavior during sleep period could result from different causes. Abnormal eating during the main sleep period has been categorized as either night eating syndrome or sleep related eating disorder. Night eating syndrome (NES is an eating disorder characterised by the clinical features of morning anorexia, evening hyperphagia, and insomnia with awakenings followed by nocturnal food ingestion. Recently night eating syndrome, conceptualized as a delayed circadian intake of food. Sleep-related eating disorder, thought to represent a parasomnia and as such included within the revised International Classification of Sleep Disorders (ICSD-2, and characterized by nocturnal partial arousals associated with recurrent episodes of involuntary food consumption and altered levels of consciousness. Whether, however, sleep-related eating disorder and night eating syndrome represent different diseases or are part of a continuum is still debated. This review summarizes their characteristics, treatment outcomes and differences between them.

  8. A Night's Sleep, Ultracheap

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ You tote your own luggage, the bed's a bit stiff, and the decor in the spartan rooms and lobby is reminiscent of a college dorm. Oh-and you can't buy a beer. But for $22 a night,the indi One Hotel is one heck of a bargain.

  9. Field evaluation of herbal mosquito repellents.

    Science.gov (United States)

    Das, N G; Nath, D R; Baruah, I; Talukdar, P K; Das, S C

    1999-12-01

    Repellent properties of Zanthoxylum armatum DC. Syn. Z. alatum Roxb. (Timur), Curcuma aromatica (Jungli haldi) and Azadirachta indica (Neem) oils were evaluated against mosquitoes in mustard (Brassica sp.) and coconut (Cocos sp.) oil base and compared with synthetic repellent. Dimethyl phthalate (DMP) as standard. Timur and jungli haldi afforded better protection in the both the base at all the concentrations. Tepellents in mustard oil gave longer protection time than those in coconut oil. At 0.57 mg/cm2 concentration timur oil gave significantly higher protection both in mustard (445 min) as well as coconut oil (404 min) than the other repellents and DMP.

  10. Do Not Go Gentle into That Good Night

    Institute of Scientific and Technical Information of China (English)

    Dylan; Thomas

    2008-01-01

    Do not go gentle into that good night,Old age should burn and rave at close of day;Rage, rage against the dying of the light.Though wise men at their end know dark is right,Because their words had forked no lightning theyDo not go gentle into that good night.

  11. Ethnobotanical study of some of mosquito repellent plants in north-eastern Tanzania

    Directory of Open Access Journals (Sweden)

    Tenu Filemoni

    2008-08-01

    Full Text Available Abstract Background The use of plant repellents against nuisance biting insects is common and its potential for malaria vector control requires evaluation in areas with different level of malaria endemicity. The essential oils of Ocimum suave and Ocimum kilimandscharicum were evaluated against malaria vectors in north-eastern Tanzania. Methodology An ethnobotanical study was conducted at Moshi in Kilimanjaro region north-eastern Tanzania, through interviews, to investigate the range of species of plants used as insect repellents. Also, bioassays were used to evaluate the protective potential of selected plants extracts against mosquitoes. Results The plant species mostly used as repellent at night are: fresh or smoke of the leaves of O. suave and O. kilimandscharicum (Lamiaceae, Azadirachta indica (Meliaceae, Eucalyptus globules (Myrtaceae and Lantana camara (Verbenaceae. The most popular repellents were O. kilimandscharicum (OK and O. suave (OS used by 67% out of 120 households interviewed. Bioassay of essential oils of the two Ocimum plants was compared with citronella and DEET to study the repellence and feeding inhibition of untreated and treated arms of volunteers. Using filter papers impregnated with Ocimum extracts, knockdown effects and mortality was investigated on malaria mosquito Anopheles arabiensis and Anopheles gambiae, including a nuisance mosquito, Culex quinquefasciatus. High biting protection (83% to 91% and feeding inhibition (71.2% to 92.5% was observed against three species of mosquitoes. Likewise the extracts of Ocimum plants induced KD90 of longer time in mosquitoes than citronella, a standard botanical repellent. Mortality induced by standard dosage of 30 mg/m2 on filter papers, scored after 24 hours was 47.3% for OK and 57% for OS, compared with 67.7% for citronella. Conclusion The use of whole plants and their products as insect repellents is common among village communities of north-eastern Tanzania and the results

  12. 微光夜视仪空间棱镜架有限元热分析%Finite Element Thermal-stress Analysis of the Space Prism Holder of Low-light Night Vision Goggles

    Institute of Scientific and Technical Information of China (English)

    高明; 王占军

    2011-01-01

    The space prism holder is a vital mechanical component of a low-light night vision goggle with single objective and two oculars.Its design has a direst impact on the imaging quality and the performance of a low- light night vision goggle.Based on the finite element analysis theory, the thermal temperature field and the thermal stress of the space prism holder's mechanical structure are studied by ANSYS.The thermal analysis of the space prism holder is made by means of creating a finite element model of mechanical structure, calculating the distribution field and analyzing the distribution and the location of thermal stress.In order to meet the need that the working temperature ranges from -30 ℃ to 50 ℃, the modified polypheylene oxid is chosen as the material of the space prism holder.The design of its mechnical structure is accomplished after the improvement in primary designed structure.%空间棱镜架是单管双目微光夜视仪机械结构重要组成部分,其设计的好坏直接影响夜视仪系统成像质量和整机性能.文中基于有限元分析理论,利用ANSYS研究了单管双目微光夜视仪空间棱镜架的温度场及热应力.通过建立结构三维有限元分析模型,计算棱镜架温度场分布,对热应变和热应力进行求解,完成空间棱镜架有限元热分析.在满足工作环境从-30℃到50℃变化条件下,对比有限元热分析求解结果,选取改性聚苯醚作为结构最终材料,改进初始结构,完成夜视仪空间棱镜架设计.

  13. Rural buyers' perception about mosquito repellants

    Directory of Open Access Journals (Sweden)

    D. MEHTA

    2010-06-01

    Full Text Available Mosquito repellants prevent mosquito bites and prevention of "man-mosquito contact" is a critical factor in transmission and spread of any disease through mosquitoes particularly in rural area. There has been a long standing 'bias' towards rural buyers. The rural markets are considered rigid in the nature but it is not the case in real sense. Marketing to rural buyers is not only a challenge to the marketers but to the manufacturers, communicators, national planners and economists as well. That is why it has been necessary to understand the various aspects of selected rural areas and consumption pattern for such a fast growing market i.e. mosquito repellants and rural buyers’ perception towards such urban products. The present paper aims to find out the factors influencing the purchase decisions of rural buyers for mosquito repellants and to study the perceptions of present and potential rural buyers' of selected mosquito repellant brands.

  14. Evaluation of repellents efficacy against Anopheles gambiae s.s.; an anthropophilic malaria vector

    Directory of Open Access Journals (Sweden)

    Gerald Katunzi

    2015-03-01

    Full Text Available Reduction of human-vector contact is of epidemiological importance in malaria control. Repellents can be used to complement the existing intervention tools against malaria vectors. Thus, evaluation of efficacy of additional mosquito repellents and /or attractants is of great significance for personal protection tools against malaria vectors. This study evaluated the repellence efficacy of menthol-propylene-glycol-carbonate (MR08 and Lemon grass (LG against Anopheles gambiae. Experiments were performed in a room which was 7.8 meters by 3.9 meters in dimension. Three experimental set ups were performed, i comparison of 10 hours worn sock and unworn sock;  ii comparison of  10 hours worn sock treated with MR08 against worn sock alone, and iii comparison of  10 hours worn sock treated with LG against worn sock alone. CDC miniature light traps were used to evaluate the recovery of released mosquitoes using both repellents and attractants. After initial trials, a concentration of 500 ppm was selected for all repellents. Among 1800 mosquitoes released into the experimental room, 1230 were recovered by CDC light traps while the remaining 570 were found within the experimental room. Among those collected by light traps, 1185 were collected by traps with worn sock alone. A worn sock treated with either MR08 or Lemon grass significantly repelled An.gambiae compared to worn sock alone. The findings of this study demonstrate that MR08 and lemon grass have inhibition efficiency against mosquito stings but further field evaluations are required for observed findings against wild populations of An.gambiae at lower Moshi using slow release method.

  15. Advanced night vision goggles

    Science.gov (United States)

    Thacker, Clinton

    2003-02-01

    The Advanced Night Vision Goggle (ANVG) program is developing integrated wide field of view (WFOV) helmet-mounted image intensifier night vision goggle systems. ANVG will provide a FOV of approximately 40° (vertical) × 100° (horizontal) and an integrated heads-up display for overlay of flight symbology and/or FLIR imagery. The added FLIR complements the I2 imagery in out of the window or ground applications. ANVG will significantly improve safety, situational awareness, and mission capabilities in differing environments. ANVG achieves the ultra wide FOV using four image intensifier tubes in a head-mounted configuration. Additional features include a miniature flat panel display and a lightweight uncooled FLIR. The integrated design will demonstrate the capability of helmet-mounted I2 and FLIR image fusion. Fusion will be accomplished optically and will offer significant opportunities for ground applications. This paper summarizes the basic technologies, lessons learned, and program status.

  16. Liquid repellency by a moving plate

    Science.gov (United States)

    Bouillant, Ambre; Anais Gauthier Team; David Quere Team; Christophe Clanet Team

    2016-11-01

    Moving solids can repel impacting drops, owing to their motion. Provided the solid velocity is larger than a threshold value, air entrained at the vicinity of the moving plate prevents the drop from wetting, and makes it bounce. In addition, the rebound is oblique, which enhances the evacuation of liquid. We discuss experiments and models on this theme, and extend them to case of small droplets (such as formed in a spray) found to be even more efficiently repelled by the moving plate.

  17. Study on optimization of lighting at night at long tunnel exit of the expressway%高速公路长隧道夜间出口照明优化研究

    Institute of Scientific and Technical Information of China (English)

    赵炜华; 刘浩学

    2012-01-01

    According to the Chinese current tunnel ventilation and lighting standards,lighting design at night at long tunnel exit of the expressway is found to have some defects.This problem is significant to traffic safety and energy conservation.In order to make lighting parameters satisfied to requirements of driving,11 drivers were selected to carry out the actual driving experiments.Pupil size parameters in real-time were recorded by eye tracker,environmental illumination at different points were detected by illumination meter and speeds were measured through the non-contact Five Wheel Meter.Experimental data were examined,and multiple curve surface logistic regression was used to obtain rules of pupil area changing with the illumination and adaptation time and the quantitative models were established.The results show that illumination at night at long tunnel exit is too high to satisfy the demands of drivers.Serious dark adaptation is caused,and traffic safety is influenced significantly.The illumination values of this segment should be optimized to gradual decrease according to the driver needs,and gradually decreased additional lighting should be equipped outside the tunnels.The lamination values can be inspected in the conclusion to lessen the effect of dark adaptation on driving.%我国现行隧道通风照明标准中,关于高速公路长隧道夜间出口段照明设计存在缺失,而上述问题对于行车安全和节能减排具有重要意义.为使高速公路长隧道出口段照明适合驾驶人需求,选用11名驾驶人进行夜间隧道实际行车试验.以眼动仪记录驾驶人瞳孔面积实时变化参数,照度计测量不同点的环境照度,非接触式五轮仪测量行车速度.运用多元曲面回归分析方法,获得瞳孔面积随照度和适应时间变化的规律,并建立量化模型.研究表明:现有隧道夜间出口段照度过高,与驾驶人实际需求差异大,造成驾驶人严重的暗适应问题;该段的照度

  18. Preliminary study on mosquito repellent and mosquitocidal activities of Ocimum gratissimum (L. grown in eastern Nigeria

    Directory of Open Access Journals (Sweden)

    Evangeline T. Oparaocha

    2010-03-01

    Full Text Available Background & objectives: The study examined the mosquito-repellent and mosquitocidal activitiesof the volatile oil of Ocimum gratissimum at three different locations (World Bank Estate, Ihitteand Umuekunne in Imo State, eastern Nigeria, with the purpose of sourcing for mosquito repellentthat is cheap, abundant, environment and user-friendly.Methods: Four different lotions; 20% (v/v and 30% (v/v concentrations each of the extractedvolatile oil in two natural oil bases (olive and palm kernel were made and six volunteered humanbaits were used to evaluate the mosquito repellent and mosquitocidal activities of the stock materialsat the three different centres from September to November 2008.Results: Topical application of each of the four different lotions significantly (p <0.05 reduced thebiting rate of mosquitoes in all the three locations tested. The 30% (v/v concentration in olive oilbase exhibiting highest average percentage repellencies of 97.2, 95.7 and 96.3% at World BankEstate, Ihitte and Umuekunne centres respectively while the 20% (v/v concentration in palmkernel oil base had the least repellency of 36.3, 41.6 and 36.3%, respectively. The other twoformulations had values ranging from 67.8 to 80% in the three locations. The 30% (v/vconcentration in both olive and palm kernel oil bases afforded all night protection against mosquitobites in all the centres, and demonstrated fast knockdown and paralyzing effect on few mosquitoesat the urban centre (World Bank Estate.Interpretation & conclusion: The study confirms that O. gratissimum grown in eastern Nigeriahas mosquito-repellent and mosquitocidal potentials and the formulations could be used to reducehuman-mosquito contacts and hence mosquito-borne diseases and irritations caused by their bites.

  19. Assessment of the repellent effect of citronella and lemon eucalyptus oil against South African Culicoides species.

    Science.gov (United States)

    Venter, Gert J; Labuschagne, Karien; Boikanyo, Solomon N B; Morey, Liesl

    2014-08-08

    The use of insect repellents to reduce the attack rate of Culicoides species (Diptera:Ceratopogonidae) should form part of an integrated control programme to combat African horse sickness and other diseases transmitted by these blood-feeding midges. In the present study the repellent effects of a commercially available mosquito repellent, a combination of citronella and lemon eucalyptus oils, on Culicoides midges was determined. The number of midges collected with two 220 V Onderstepoort traps fitted with 8 W 23 cm white light tubes and baited with peel-stick patches, each containing 40 mg of active ingredient, was compared with that of two unbaited traps. Two trials were conducted and in each trial the four traps were rotated in two replicates of a 4 x 4 randomised Latin square design. Although more midges were collected in the baited traps, the mean number in the baited and unbaited traps was not significantly different. This mosquito repellent did not influence either the species composition or the physiological groups of Culicoides imicola Kieffer. The higher mean numbers in the baited traps, although not statistically significant, may indicate that this mosquito repellent might even attract Culicoides midges under certain conditions.

  20. Monoterpenes from thyme (Thymus vulgaris) as potential mosquito repellents.

    Science.gov (United States)

    Park, Byeoung-Soo; Choi, Won-Sik; Kim, Jeong-Han; Kim, Kap-Ho; Lee, Sung-Eun

    2005-03-01

    Five monoterpenes (carvacrol, p-cymene, linalool, alpha-terpinene, and thymol) derived from the essential oil of thyme (Thymus vulgaris) were examined for their repellency against the mosquito Culex pipiens pallens. All 5 monoterpenes effectively repelled mosquitoes based on a human forearm bioassay. Alpha-terpinene and carvacrol showed significantly greater repellency than a commercial formulation, N,N-diethyl-m-methylbenzamide (deet), whereas thymol showed similar repellency to that of deet. The duration of repellency after application for all these monoterpenes was equal to or higher than that of deet. These findings indicate that a spray-type solution containing 2% alpha-terpinene may serve as an alternative mosquito repellent.

  1. Can topical insect repellents reduce malaria? A cluster-randomised controlled trial of the insect repellent N,N-diethyl-m-toluamide (DEET in Lao PDR.

    Directory of Open Access Journals (Sweden)

    Vanessa Chen-Hussey

    Full Text Available BACKGROUND: Mosquito vectors of malaria in Southeast Asia readily feed outdoors making malaria control through indoor insecticides such as long-lasting insecticidal nets (LLINs and indoor residual spraying more difficult. Topical insect repellents may be able to protect users from outdoor biting, thereby providing additional protection above the current best practice of LLINs. METHODS AND FINDINGS: A double blind, household randomised, placebo-controlled trial of insect repellent to reduce malaria was carried out in southern Lao PDR to determine whether the use of repellent and long-lasting insecticidal nets (LLINs could reduce malaria more than LLINs alone. A total of 1,597 households, including 7,979 participants, were recruited in June 2009 and April 2010. Equal group allocation, stratified by village, was used to randomise 795 households to a 15% DEET lotion and the remainder were given a placebo lotion. Participants, field staff and data analysts were blinded to the group assignment until data analysis had been completed. All households received new LLINs. Participants were asked to apply their lotion to exposed skin every evening and sleep under the LLINs each night. Plasmodium falciparum and P. vivax cases were actively identified by monthly rapid diagnostic tests. Intention to treat analysis found no effect from the use of repellent on malaria incidence (hazard ratio: 1.00, 95% CI: 0.99-1.01, p = 0.868. A higher socio-economic score was found to significantly decrease malaria risk (hazard ratio: 0.72, 95% CI: 0.58-0.90, p = 0.004. Women were also found to have a reduced risk of infection (hazard ratio: 0.59, 95% CI: 0.37-0.92, p = 0.020. According to protocol analysis which excluded participants using the lotions less than 90% of the time found similar results with no effect from the use of repellent. CONCLUSIONS: This randomised controlled trial suggests that topical repellents are not a suitable intervention in addition to

  2. ATLAS Nightly Build System Upgrade

    CERN Document Server

    Dimitrov, G; The ATLAS collaboration; Simmons, B; Undrus, A

    2014-01-01

    The ATLAS Nightly Build System is a facility for automatic production of software releases. Being the major component of ATLAS software infrastructure, it supports more than 50 multi-platform branches of nightly releases and provides ample opportunities for testing new packages, for verifying patches to existing software, and for migrating to new platforms and compilers. The Nightly System testing framework runs several hundred integration tests of different granularity and purpose. The nightly releases are distributed and validated, and some are transformed into stable releases used for data processing worldwide. The first LHC long shutdown (2013-2015) activities will elicit increased load on the Nightly System as additional releases and builds are needed to exploit new programming techniques, languages, and profiling tools. This paper describes the plan of the ATLAS Nightly Build System Long Shutdown upgrade. It brings modern database and web technologies into the Nightly System, improves monitoring of nigh...

  3. ATLAS Nightly Build System Upgrade

    CERN Document Server

    Dimitrov, G; The ATLAS collaboration; Simmons, B; Undrus, A

    2013-01-01

    The ATLAS Nightly Build System is a facility for automatic production of software releases. Being the major component of ATLAS software infrastructure, it supports more than 50 multi-platform branches of nightly releases and provides ample opportunities for testing new packages, for verifying patches to existing software, and for migrating to new platforms and compilers. The Nightly System testing framework runs several hundred integration tests of different granularity and purpose. The nightly releases are distributed and validated, and some are transformed into stable releases used for data processing worldwide. The first LHC long shutdown (2013-2015) activities will elicit increased load on the Nightly System as additional releases and builds are needed to exploit new programming techniques, languages, and profiling tools. This paper describes the plan of the ATLAS Nightly Build System Long Shutdown upgrade. It brings modern database and web technologies into the Nightly System, improves monitoring of nigh...

  4. Simplified Night Sky Display System

    Science.gov (United States)

    Castellano, Timothy P.

    2010-01-01

    A document describes a simple night sky display system that is portable, lightweight, and includes, at most, four components in its simplest configuration. The total volume of this system is no more than 10(sup 6) cm(sup 3) in a disassembled state, and weighs no more than 20 kilograms. The four basic components are a computer, a projector, a spherical light-reflecting first surface and mount, and a spherical second surface for display. The computer has temporary or permanent memory that contains at least one signal representing one or more images of a portion of the sky when viewed from an arbitrary position, and at a selected time. The first surface reflector is spherical and receives and reflects the image from the projector onto the second surface, which is shaped like a hemisphere. This system may be used to simulate selected portions of the night sky, preserving the appearance and kinesthetic sense of the celestial sphere surrounding the Earth or any other point in space. These points will then show motions of planets, stars, galaxies, nebulae, and comets that are visible from that position. The images may be motionless, or move with the passage of time. The array of images presented, and vantage points in space, are limited only by the computer software that is available, or can be developed. An optional approach is to have the screen (second surface) self-inflate by means of gas within the enclosed volume, and then self-regulate that gas in order to support itself without any other mechanical support.

  5. The Sky at Night

    CERN Document Server

    Moore, Patrick

    2010-01-01

    For more than 50 years now Sir Patrick Moore has presented the BBC Television series Sky at Night; not a month has been missed – a record for any television series, and a record which may never be broken. Every three years or so a book is published covering the main events in both astronomy and space research. This is the 13th volume, not only a record of the programmes but also of the great advances and discoveries during the period covered - eclipses, comets, and the strange chemical lakes of Titan, for instance, but also anniversaries such as the fifteenth “birthday” of the Hubble Space Telescope, and not forgetting the programme celebrating the Sky at Night’s 50th year, attended by astronaut Piers Sellars and many others who appeared on the programme over the years. All the chapters are self-contained, and fully illustrated. In this new Sky at Night book you will find much to entertain you. It will appeal to amateurs and professionals alike.

  6. Insect Repellents: Protect Your Child from Insect Bites

    Science.gov (United States)

    ... Español Text Size Email Print Share Choosing an Insect Repellent for Your Child Page Content Mosquitoes, biting ... sunscreen needs to be reapplied often. Reactions to Insect Repellents If you suspect that your child is ...

  7. Repellence and toxicity of Schinus molle extracts on Blattella germanica.

    Science.gov (United States)

    Ferrero, A A; Chopa, C Sánchez; González, J O Werdin; Alzogaray, R A

    2007-06-01

    The biological activities of ethanol and petroleum ether extracts from leaves and fruits of Schinus molle against adults of Blattella germanica were examined by repellence test and topical application. All extracts produced significant repellent effect and mortality.

  8. New device for monitoring the colors of the night

    Science.gov (United States)

    Spoelstra, Henk

    2014-05-01

    The introduction of LED lighting in the outdoor environment may increase the amount of blue light in the night sky color spectrum. This can cause more light pollution due to Rayleigh scattering of the shorter wavelengths. Blue light may also have an impact on circadian rhythm of humans due to the suppression of melatonin. At present no long-term data sets of the color spectrum of the night sky are available. In order to facilitate the monitoring of levels and variations in the night sky spectrum, a low cost multi-filter instrument has been developed. Design considerations are described as well as the choice of suitable filters, which are critical - especially in the green wavelength band from 500 to 600 nm. Filters from the optical industry were chosen for this band because available astronomical filters exclude some or all of the low and high-pressure sodium lines from lamps, which are important in light pollution research. Correction factors are calculated to correct for the detector response and filter transmissions. Results at a suburban monitoring station showed that the light levels between 500 and 600 nm are dominant during clear and cloudy skies. The relative contribution of blue light increases with a clear moonless night sky. The change in color spectrum of the night sky under moonlit skies is more complex and is still under study.

  9. Buffer zone water repellency: effects of the management practice

    OpenAIRE

    Rasa, Kimmo; Räty, Mari; Nikolenko, Olga; Horn, Rainer; Yli-Halla, Markku; Uusi-Kämppä, Jaana; Pietola, Liisa

    2006-01-01

    Water repellency index R was measured in a heavy clay and a sandy loam, used as arable land or buffer zone (BZ). Further, effect of management practise and ageing of BZs were studied. Water repellency was proved to be a common phenomenon on these soils. Harvesting and grazing increased water repellency as does ageing.Low water repellency is supposed to prevent preferential flows and provide evenly distributed water infiltration pattern through large soil volume, which favours nutrient retention.

  10. Moisture variability resulting from water repellency in Dutch soils

    OpenAIRE

    Dekker, L.W.

    1998-01-01

    The present study suggests that many soils in the Netherlands, in natural as well as in agricultural areas, may be water repellent to some degree, challenging the common perception that soil water repellency is only an interesting aberration. When dry, water repellent soils resist or retard water infiltration into the soil matrix. Soil water repellency can lead to the development of unstable wetting and preferential flow paths. Preferential flow has wide-ranging significance for rapi...

  11. The hydrology of water repellent soils

    Science.gov (United States)

    Shillito, R.; Berli, M.; Ghezzehei, T. A.; Moore, H. K.

    2016-12-01

    The occurrence of wildfire throughout the western U.S. is expected to increase. So, too, will flooding and erosion associated with the aftereffects of the fires. Soil water repellency (hydrophobicity) has frequently been observed after fires and is believed to increase the post-fire runoff potential, although current runoff models cannot directly account for this effect. Many physically-based runoff models incorporate an infiltration reduction factor or manipulate the soil hydraulic conductivity parameter to account for water-repellent soils in runoff generation. Beginning with fundamental principles, we developed a methodology to physically account for soil water repellency and directly account for it in the Kineros2 runoff and erosion model.

  12. Nightly Test system migration

    CERN Document Server

    Win-Lime, Kevin

    2013-01-01

    The summer student program allows students to participate to the Cern adventure. They can follow several interesting lectures about particle science and participate to the experiment work. As a summer student, I had worked for LHCb experiment. LHCb uses a lot of software to analyze its data. All this software is organized in packages and projects. They are built and tested during the night using an automated system and the results are displayed on a web interface. Actually, LHCb is changing this system. It is looking for a replacement candidate. So I was charged to unify some internal interfaces to permit a swift migration. In this document, I will describe shortly the system used by LHCb, then I will explain what I have done in detail.

  13. Repellency of cassia bark, eucalyptus, and star anise oils and their major constituents to Leptotrombidium pallidum (Acari: Trombiculidae).

    Science.gov (United States)

    Shin, E-Hyun; Song, Bong Gu; Lee, Il Hee; Park, Mi Yeoun; Ahn, Young-Joon; Chang, Kyu-Sik

    2013-05-01

    Leptotrombidium pallidum (Nagoya, Miyagawa, Mitamura & Tamiya) is a primary vector of Orientia tsutsugamushi (Hyashi), the causative agent of scrub typhus. An assessment is made of the repellency to L. pallidum larvae (chiggers) of cassia bark, eucalyptus, and star anise oils and major constituents (E)-cinnamaldehyde, 1,8-cineole, and (E)-anethole of the corresponding oils. Results were compared with those of conventional repellents DEET (N,N-diethyl-3-methylbenzamide), IR3535 [(ethyl 3-[acetyl(butyl)amino]propanoate)], and permethrin. Based on the median repellent concentration (RC50) values, (E)-cinnamaldehyde, (E)-anethole, cassia bark oil, and star anise oil (RC50, 0.95-1.52 mg/cm2) exhibited significantly more potent repellency than DEET (3.85 mg/cm2). (E)-cinnamaldehyde, (E)-anethole, cassiabark oil, 1,8-cineole, and star anise oil were approximately 43, 16, 11, 8, and 4 times more effective than IR3535 (CC5, 6.51%) as judged by the median climbing distance-disturbing concentration (CC50) values. The median residual duration time of repellency (RT50) was significantly more pronounced in DEET (RT50, 323 min) than in all essential oils and constituents (108-167 min). In the light of global efforts to reduce the level of highly toxic synthetic repellents, the three essential oils and their major constituents described merit further study as potential biorepellents for the control of L. pallidum populations.

  14. Moisture variability resulting from water repellency in Dutch soils.

    NARCIS (Netherlands)

    Dekker, L.W.

    1998-01-01

    The present study suggests that many soils in the Netherlands, in natural as well as in agricultural areas, may be water repellent to some degree, challenging the common perception that soil water repellency is only an interesting aberration. When dry, water repellent soils resist or retard water in

  15. Moisture variability resulting from water repellency in Dutch soils

    NARCIS (Netherlands)

    Dekker, L.W.

    1998-01-01

    The present study suggests that many soils in the Netherlands, in natural as well as in agricultural areas, may be water repellent to some degree, challenging the common perception that soil water repellency is only an interesting aberration. When dry, water repellent soils resist or retard

  16. Water repellent soils: a state-of-the-art

    Science.gov (United States)

    Leonard F. DeBano

    1981-01-01

    Water repellency in soils was first described by Schreiner and Shorey (1910), who found that some soils in California could not be wetted and thereby were not suitable for agriculture. Waxy organic substances were responsible for the water repellency. Other studies in the early 1900's on the fairy ring phenomenon suggested that water repellency could be caused by...

  17. Urban planning and traffic safety at night

    Science.gov (United States)

    Ispas, N.; Trusca, D.

    2016-08-01

    Urban planning including traffic signs serve vital functions, providing road users with regulatory, warning and guidance information about the roadway and surrounding environment. There are a large number of signs and even more guidelines on how these signs should be designed, installed, and maintained in concordance with on road surface traffic signs. More requirements for signs are made for night urban traffic, including appearance (size, shape, colour), placement (height, lateral, and longitudinal), maintenance (visibility, position, damage) and signs light and retroreflective. In the night, traffic signs visibility can interact by on pedestrian visibility and diminish urban traffic safety. The main aim of this paper are the scientific determination of an urban specific zone visibility for evaluate at night real conditions in case of a traffic accident in the Braşov city area. The night visibility study was made using PC-Rect version 4.2. Other goal of the paper was to modify some urban planning solution in order to increase the urban safety in Brașov.

  18. Soft, elastic, water-repellent materials

    Science.gov (United States)

    Coux, Martin; Clanet, Christophe; Quéré, David

    2017-06-01

    Small hydrophobic textures at solid surfaces provide water repellency, a situation whose detailed properties critically depend on the geometry of textures. Depending on their size, density, and shape, water slip, rain repellency, or antifogging can be achieved. Here, we discuss how the use of soft, elastic materials allows us to tune reversibly the texture density by stretching or relaxing the materials, which is found to impact water adhesion and rebounds. In addition, solid deformations can also be exploited to largely vary the shape of Wenzel drops, a consequence of the strong pinning of water in this state.

  19. Night Sky Quality Measurements at the ATA50 Telescope

    Science.gov (United States)

    Er, Hüseyin; Nasiroglu, Ilham; Guney, Yavuz

    2016-07-01

    One of the most important factor affecting the quality of the sky in astronomy is the light pollution (luminance of the night sky). Light pollution, also affects humans and wildlife in many ways. This effect occurs by using the light source of outdoor lighting in the wrong way. Light pollution can be reduced by lighting only what is actually needed, when and where it is needed. In generally, SQM (Sky Quality Meter- Clear Sky Detector) is used to measure this light effect. In this work we present night sky brightness measurements performed at the Atatürk University Astrophysics Research Telescope (ATA50) and the surrounding area, Erzurum, TURKEY. We also discussed the physical impacts of light pollution on science, humans and wildlife.

  20. Aircraft Lighting and Transparency Lab

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Lighting and Transparencies with Night Combat Lab performs radiometric and photometric measurements of cockpit lighting and displays. Evaluates the day,...

  1. Night vision goggles resolution performance at low contrast levels

    Science.gov (United States)

    Tjernstrom, Lars

    1993-01-01

    NVG (Night Vision Goggle) resolution performance data is usually given as measured against high contrast, black and white, targets. When NVGs are used as night vision aids for visual night flight, the scene viewed by the pilot is in most cases dominated by low contrast. Therefore, NVG performance at low contrast levels is more relevant to the piloting task than NVG resolution at high contrast levels. A set of resolution targets with different contrast levels was designed and ground tests performed at various light levels outdoors at night. The results showed a marked loss of resolution at lower contrast levels. The presentation will describe the test method, give the results and discuss how the results may be explained. A method for using the test results as the basis for correlating piloting performance to light levels will be presented.

  2. All Sky Camera instrument for night sky monitoring

    CERN Document Server

    Mandat, Dusan; Hrabovsky, Miroslav; Schovanek, Petr; Palatka, Miroslav; Travnicek, Petr; Prouza, Michael; Ebr, Jan

    2014-01-01

    The All Sky Camera (ASC) was developed as an universal device for a monitoring of the night sky quality and night sky background measurement. ASC system consists of an astronomical CCD camera, a fish eye lens, a control computer and associated electronics. The measurement is carried out during astronomical twilight. The analysis results are the cloud fraction (the percentage of the sky covered by clouds), night sky brightness (in mag/arcsec2) and light background in the field of view of the camera. The analysis of the cloud fraction is based on the astrometry (comparison to catalogue positions) of the observed stars.

  3. Effectiveness of Gel Repellents on Feral Pigeons

    Directory of Open Access Journals (Sweden)

    Birte Stock

    2013-12-01

    Full Text Available Millions of feral pigeons (Columba livia live in close association with the human population in our cities. They pose serious health risks to humans and lead to high economic loss due to damage caused to buildings. Consequently, house owners and city authorities are not willing to allow pigeons on their buildings. While various avian repellents are regularly introduced onto the market, scientific proof of efficacy is lacking. This study aimed at testing the effectiveness of two avian gel repellents and additionally examined their application from animal welfare standpoint. The gels used an alleged tactile or visual aversion of the birds, reinforced by additional sensory cues. We mounted experimental shelves with the installed repellents in a pigeon loft and observed the behavior of free-living feral pigeons towards the systems. Both gels showed a restricted, transient repellent effect, but failed to prove the claimed complete effectiveness. Additionally, the gels’ adhesive effect remains doubtful in view of animal welfare because gluing of plumage presents a risk to feral pigeons and also to other non-target birds. This study infers that both gels lack the promised complete efficacy, conflict with animal welfare concerns and are therefore not suitable for feral pigeon management in urban areas.

  4. Mosquito repellency of novel Trifluoromethylphenyl amides

    Science.gov (United States)

    Human diseases caused by mosquito-transmitted pathogens include malaria, dengue and yellow fever and are responsible for several million human deaths every year, according to the World Health Organization (WHO). Our current research projects focus on the development of new insecticides and repellent...

  5. Uneven moisture patterns in water repellent soils

    NARCIS (Netherlands)

    Dekker, L.W.; Ritsema, C.J.

    1996-01-01

    In the Netherlands, water-repellent soils are widespread and they often show irregular moisture patterns, which cause accelerated transport of water and solutes to the groundwater and surface water. Under grass cover, spatial variability in soil moisture content is high owing to fingered flow; in ar

  6. Mode of action of insect repellents

    Science.gov (United States)

    The mode of action of DEET and other insect repellents has been a topic of interest since the discovery of DEET in the mid twentieth century. Nearly 60 years have passed since DEET applied topically to the skin was shown to be effective in preventing mosquito bites. With the discovery and characte...

  7. Methods for determining actual soil water repellence

    NARCIS (Netherlands)

    Dekker, L.W.; Ritsema, C.J.; Oostindie, K.; Moore, D.; Wesseling, J.G.

    2009-01-01

    In this paper we describe a simple and quick method for determining the presence of water repellency in a soil by using a small core sampler (1.5 cm in diameter, 25 cm long) and applying the water drop penetration time (WDPT) test at different depths on the sandy soil cores. Obtained results provide

  8. Manufacturing and characterisation of water repellent surfaces

    DEFF Research Database (Denmark)

    De Grave, Arnaud; Botija, Pablo; Hansen, Hans Nørgaard

    2006-01-01

    design criteria for such surfaces. The problem of adapting this behaviour to artificially roughened surfaces is addressed by providing design criteria for superhydrophobic, water-repellent and self-cleaning surfaces according to the concrete performance desired for them. Different kind of manufacturing...

  9. Pest repelling properties of ant pheromones

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2014-01-01

    Ants control pests via predation and physical deterrence; however, ant communication is based on chemical cues which may serve as warning signals to potential prey and other intruders. The presence of ant pheromones may, thus, be sufficient to repel pests from ant territories. This mini...

  10. Comparison of Repellency Effect of Mosquito Repellents for DEET, Citronella, and Fennel Oil

    Science.gov (United States)

    Yoon, Jong Kwang; Kim, Kang-Chang; Cho, Yeondong; Gwon, Yong-Dae; Cho, Han Sam; Heo, Yoonki; Park, Kihoon; Lee, Yang-Won; Kim, Mijeong; Oh, Yu-Kyoung; Kim, Young Bong

    2015-01-01

    To confirm that Korean Food and Drug Administration (KFDA) guidelines are applicable to test the efficacy of mosquito repellents, these guidelines were used to test the efficacy and complete protection times (CPTs) of three representative mosquito repellents: N,N-diethyl-3-methylbenzamide (DEET), citronella, and fennel oil. The repellency of citronella oil decreased over time, from 97.9% at 0 h to 71.4% at 1 h and 57.7% at 2 h, as did the repellency of fennel oil, from 88.6% at 0 h to 61.2% at 1 h and 47.4% at 2 h. In contrast, the repellency of DEET remained over 90% for 6 h. The CPT of DEET (360 min) was much longer than the CPTs of citronella (10.5 min) and fennel oil (8.4 min). These results did not differ significantly from previous findings, and hence confirm that the KFDA guidelines are applicable for testing the efficacy of mosquito repellents. PMID:26527362

  11. Typical Monoterpenes as Insecticides and Repellents against Stored Grain Pests

    Directory of Open Access Journals (Sweden)

    Suelen L. Reis

    2016-02-01

    Full Text Available Five monoterpenes naturally occurring in essential oils were tested for their insecticidal and repellent activities against the bruchid beetle Callosobruchus maculatus and the maize weevil Sitophilus zeamais. The monoterpenes were highly efficient as inducers of mortality or repellency against both insect species. They were more efficient in their fumigant activity against C. maculatus than against S. zeamais, while this profile of action was inverted when considering the repellent activities. Eugenol was one the most effective fumigants against both insects and one the most effective repellent against C. maculatus, while citronellal and geranial were one the most effective repellents against S. zeamais. Functional and positional isomerism of the monoterpenes pairs appears to exert little or no influence on theirs effects, especially in case of repellency. The validation of the insecticidal/repellent efficacy of isolated monoterpenes may permit a more advantageous, rapid, economic and optimized approach to the identification of promising oils for commercial formulations when combined with ethnobotanical strategies.

  12. PERBANDINGAN EFEKTIFITAS REPELLENT KOMERSIL DENGAN EKSTRAK KULIT JERUK PURUT UNTUK MENCEGAH GIGITAN NYAMUK Aedes aegypti

    OpenAIRE

    Wana; Ishak, Hasanuddin; Manyullei, Syamsuar

    2015-01-01

    Repellent merupakan bahan yang mempunyai kemampuan untuk melindungi manusia dari gigitan nyamuk. Repellent kimia yang paling sering digunakan adalah repellent yang mengandung DEET yang beredar di supermarket, pasaran maupun warung-warung kecil. Selain itu adapula repellent alami yang dapat digunakan, yaitu kandungan minyak atsiri pada kulit jeruk purut. Penelitian ini bertujuan untuk membandingkan efektivitas repellent komersil yaitu repellent merek SL dan repellent alami yaitu minyak at...

  13. Plant products used as mosquito repellents in Guinea Bissau, West Africa.

    Science.gov (United States)

    Pålsson, K; Jaenson, T G

    1999-01-15

    By standardized interviews of people in 23 rural villages, in the Oio region of Guinea Bissau, we collected data on which plant species and plant derived products or methods people use to reduce mosquito biting activity. The following plants were used to reduce numbers of mosquitoes indoors at night: fresh or smouldering Hyptis suaveolens Poit. (Lamiaceae), smoke of the bark of Daniellia oliveri Rolfe (Caesalpiniaceae), smoke of the infructescence of Elaeis guineensis Jacq. (Arecaceae), smoke of the seed capsules of Parkia biglobosa (Jacq.) Benth. (Mimosaceae), smoke of the leaves of Azadirachta indica A.Juss. (Meliaceae) and Eucalyptus sp. (Myrtaceae), fresh Ocimum canum Sims (Lamiaceae), and fresh Senna occidentalis (L.) Link (Caesalpiniaceae). In two field experiments we estimated the 'repellent activity' of certain of these plants and compared their efficacies with those of two commercially available mosquito repellents, i.e. 'positive' controls. In the first experiment we tested: smouldering H. suaveolens (85.4% repellency); fresh H. suaveolens (73.2%); burning of the bark of D. oliveri (74.7%); and smoke of the leaves of Eucalyptus (72.2%). In the second experiment we tested: smouldering H. suaveolens (83.6% repellency); fresh H. suaveolens (66.5%); burning of the bark of D. oliveri (77.9%); smoke of the leaves of A. indica (76.0%); smoke of the infructescence of E. guineensis (69.0%); fresh O. canum (63.6%); and fresh S. occidentalis; (29.4%). All the products tested, except S. occidentalis were significantly more effective than the negative control.

  14. [Night workers and plasmatic cortisol].

    Science.gov (United States)

    Palermo, P; Rosati, M V; Ciarrocca, M; Nicassio, P; Piccoli, F; Cerratti, D; Anzani, M F; Tomei, G; Perugi, F; Monti, C; Palitti, T; Tomao, E; Caciari, T; Tomei, F

    2007-01-01

    The aim of the study is to evaluate whether occupational exposure to night work could cause alterations in the levels of plasmatic cortisol. The interest toward this argument arises form several studies in scientific literature referring the presence of an alteration in the synthesis and release of cortisol in workers exposed to night work. We studied a population of workers employed in night security service and monitoring service of alarm systems in different museums compared to a control group not performing shift-work and/or night work. The exposed and control subjects were compared by age, length of service, smoking habit (n. cigarettes per day), habitual consumption of alcoholic drinks (n. glass of wine/beer per day). We evaluated the levels of plasmatic cortisol on 50 workers exposed to night work, all males of whom 30 smokers and 20 non-smokers and on 50 controls of whom 30 smokers and 20 non-smokers.

  15. Lighting

    Data.gov (United States)

    Federal Laboratory Consortium — Lighting Systems Test Facilities aid research that improves the energy efficiency of lighting systems. • Gonio-Photometer: Measures illuminance from each portion of...

  16. Light

    DEFF Research Database (Denmark)

    Prescott, N.B.; Kristensen, Helle Halkjær; Wathes, C.M.

    2004-01-01

    This chapter presents the effect of artificial light environments (light levels, colour, photoperiod and flicker) on the welfare of broilers in terms of vision, behaviour, lameness and mortality......This chapter presents the effect of artificial light environments (light levels, colour, photoperiod and flicker) on the welfare of broilers in terms of vision, behaviour, lameness and mortality...

  17. Limitation of using synthetic human odours to test mosquito repellents

    Directory of Open Access Journals (Sweden)

    Mbeyela Edgar

    2009-07-01

    Full Text Available Abstract Background Gold-standard tests of mosquito repellents involve exposing human volunteers to host-seeking mosquitoes, to assess the protective efficacy of the repellents. These techniques are not exposure-free and cannot be performed prior to toxicological evaluation. It is postulated that synthetic lures could provide a useful assay that mimics in-vivo conditions for use in high-throughput screening for mosquito repellents. Methods This paper reports on a semi-field evaluation of repellents using a synthetic blend of human derived attractants for the malaria vector, Anopheles gambiae sensu stricto Different concentrations of known repellents, N, N diethyl-3-methylbenzamide (deet and Para-methane-3, 8, diol (PMD were added into traps baited with the synthetic blend, and resulting changes in mosquito catches were measured. Results All test concentrations of deet (0.001% to 100% reduced the attractiveness of the synthetic blend. However, PMD was repellent only at 0.25%. Above this concentration, it significantly increased the attractiveness of the blend. There was no relationship between the repellent concentrations and the change in mosquito catches when either deet (r2 = 0.033, P = 0.302 or PMD (r2 = 0.020, P = 0.578 was used. Conclusion It is concluded that while some repellents may reduce the attractiveness of synthetic human odours, others may instead increase their attractiveness. Such inconsistencies indicate that even though the synthetic attractants may provide exposure-free and consistent test media for repellents, careful selection and multiple-repellent tests are necessary to ascertain their suitability for use in repellent screening. The synthetic odour blend tested here is not yet sufficiently refined to serve as replacement for humans in repellent testing, but may be developed further and evaluated in different formats for exposure free repellent testing purposes.

  18. Assessment of night vision problems in patients with congenital stationary night blindness.

    Directory of Open Access Journals (Sweden)

    Mieke M C Bijveld

    Full Text Available Congenital Stationary Night Blindness (CSNB is a retinal disorder caused by a signal transmission defect between photoreceptors and bipolar cells. CSNB can be subdivided in CSNB2 (rod signal transmission reduced and CSNB1 (rod signal transmission absent. The present study is the first in which night vision problems are assessed in CSNB patients in a systematic way, with the purpose of improving rehabilitation for these patients. We assessed the night vision problems of 13 CSNB2 patients and 9 CSNB1 patients by means of a questionnaire on low luminance situations. We furthermore investigated their dark adapted visual functions by the Goldmann Weekers dark adaptation curve, a dark adapted static visual field, and a two-dimensional version of the "Light Lab". In the latter test, a digital image of a living room with objects was projected on a screen. While increasing the luminance of the image, we asked the patients to report on detection and recognition of objects. The questionnaire showed that the CSNB2 patients hardly experienced any night vision problems, while all CSNB1 patients experienced some problems although they generally did not describe them as severe. The three scotopic tests showed minimally to moderately decreased dark adapted visual functions in the CSNB2 patients, with differences between patients. In contrast, the dark adapted visual functions of the CSNB1 patients were more severely affected, but showed almost no differences between patients. The results from the "2D Light Lab" showed that all CSNB1 patients were blind at low intensities (equal to starlight, but quickly regained vision at higher intensities (full moonlight. Just above their dark adapted thresholds both CSNB1 and CSNB2 patients had normal visual fields. From the results we conclude that night vision problems in CSNB, in contrast to what the name suggests, are not conspicuous and generally not disabling.

  19. Night or darkness, which intensifies the feeling of fear?

    Science.gov (United States)

    Li, Yadan; Ma, Wenjuan; Kang, Qin; Qiao, Lei; Tang, Dandan; Qiu, Jiang; Zhang, Qinglin; Li, Hong

    2015-07-01

    Nighttime fear is a phenomenon in which people feel more afraid of threats at night. Despite the vast amount of psychological research on nighttime fear, previous researchers have not accurately distinguished between "night" and "darkness", both of which play important roles in nighttime fear. We collected physiological (skin conductance response and heart rate) and psychological (self-report) data simultaneously to investigate the effects of "night" and "darkness" on fearful feelings and whether these effects were moderated by the mode of stimulus delivery (i.e., visual or auditory). Specifically, two tasks were employed in which time (day vs. night), illumination (light vs. darkness) and stimulus type (fearful vs. neutral) were manipulated. Participants (n=128) were exposed to visual and auditory oddball tasks consisting of fearful and neutral stimuli. The results indicated that there were significant increases in fear responses at night, and the difference between day and night was significant for fear stimuli but not for neutral events. Furthermore, these effects were consistent over different sensory modalities (visual and auditory). The results of this study underscore the importance of the day-night cycle in fear-related information processing and suggest that further attention needs to be paid to the influence of the biological circadian rhythm on these processes. The current findings could inform a deeper understanding of anxiety and fear-related disorders, and thus, we invite future studies to illuminate the underlying neurobiological mechanisms therein. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. The night before your surgery - children

    Science.gov (United States)

    Surgery - child; Preoperative - night before ... food after 11 p.m. the night before surgery. Your child should not eat or drink any ... child the night before or the day of surgery, call the doctor. Stop giving your child any ...

  1. Insect photoreceptor adaptations to night vision.

    Science.gov (United States)

    Honkanen, Anna; Immonen, Esa-Ville; Salmela, Iikka; Heimonen, Kyösti; Weckström, Matti

    2017-04-05

    Night vision is ultimately about extracting information from a noisy visual input. Several species of nocturnal insects exhibit complex visually guided behaviour in conditions where most animals are practically blind. The compound eyes of nocturnal insects produce strong responses to single photons and process them into meaningful neural signals, which are amplified by specialized neuroanatomical structures. While a lot is known about the light responses and the anatomical structures that promote pooling of responses to increase sensitivity, there is still a dearth of knowledge on the physiology of night vision. Retinal photoreceptors form the first bottleneck for the transfer of visual information. In this review, we cover the basics of what is known about physiological adaptations of insect photoreceptors for low-light vision. We will also discuss major enigmas of some of the functional properties of nocturnal photoreceptors, and describe recent advances in methodologies that may help to solve them and broaden the field of insect vision research to new model animals.This article is part of the themed issue 'Vision in dim light'.

  2. Discover POPSCIENCE on Researchers' Night

    CERN Multimedia

    The POPSCIENCE Team

    2014-01-01

    On Friday 26 September 2014, CERN will be celebrating European Researchers' Night at three venues in Geneva and St. Genis-Pouilly. Inspired by Andy Warhol, this year's theme is “Pop science is for everyone”.     Every year, on the last Friday of September, the European Researchers’ Night takes place in about 300 cities all over Europe, with funding from the EU, to promote research and highlight researchers in engaging and fun ways for the general public. Andy Warhol said, “Pop art is for everyone”. This year, “Pop science is for everyone” is the motto of the Researchers’ Night event organised by CERN and its partners*. The night will offer everyone the opportunity to learn about the latest discoveries in physics and cosmology through poetry, theatre and music. This will be in addition to the event's traditional activities for the general public. To attract new audiences,...

  3. Discover POPSCIENCE on Researchers' Night

    CERN Multimedia

    The POPSCIENCE Team

    2014-01-01

    On Friday 26 September 2014, CERN will be celebrating European Researchers' Night at three venues in Geneva and St. Genis-Pouilly. Inspired by Andy Warhol, this year's theme is “Pop science is for everyone”.     Every year, on the last Friday of September, the European Researchers’ Night takes place in about 300 cities all over Europe, with funding from the EU, to promote research and highlight researchers in engaging and fun ways for the general public. Andy Warhol said, “Pop art is for everyone”. This year, “Pop science is for everyone” is the motto of the Researchers’ Night event organised by CERN and its partners*. The night will offer everyone the opportunity to learn about the latest discoveries in physics and cosmology through poetry, theatre and music. This will be in addition to the event's traditional activities for the general public. To attract new audiences,...

  4. Soil water repellency changes with depth and relationship to physical properties within wettable and repellent soil profiles

    Directory of Open Access Journals (Sweden)

    Sepehrnia Nasrollah

    2017-03-01

    Full Text Available This study explored the effect of soil water repellency (SWR on soil hydrophysical properties with depth. Soils were sampled from two distinctly wettable and water repellent soil profiles at depth increments from 0-60 cm. The soils were selected because they appeared to either wet readily (wettable or remain dry (water repellent under field conditions. Basic soil properties (MWD, SOM, θv were compared to hydrophysical properties (Ks, Sw, Se, Sww, Swh, WDPT, RIc, RIm and WRCT that characterise or are affected by water repellency. Our results showed both soil and depth affected basic and hydrophysical properties of the soils (p <0.001. Soil organic matter (SOM was the major property responsible for water repellency at the selected depths (0-60. Water repellency changes affected moisture distribution and resulted in the upper layer (0-40 cm of the repellent soil to be considerably drier compared to the wettable soil. The water repellent soil also had greater MWDdry and Ks over the entire 0-60 cm depth compared to the wettable soil. Various measures of sorptivity, Sw, Se, Sww, Swh, were greater through the wettable than water repellent soil profile, which was also reflected in field and dry WDPT measurements. However, the wettable soil had subcritical water repellency, so the range of data was used to compare indices of water repellency. WRCT and RIm had less variation compared to WDPT and RIc. Estimating water repellency using WRCT and RIm indicated that these indices can detect the degree of SWR and are able to better classify SWR degree of the subcritical-repellent soil from the wettable soil.

  5. Rural buyers' perception about mosquito repellants

    OpenAIRE

    Mehta, D.; Anand GARG; Naveen K MEHTA

    2010-01-01

    Mosquito repellants prevent mosquito bites and prevention of "man-mosquito contact" is a critical factor in transmission and spread of any disease through mosquitoes particularly in rural area. There has been a long standing 'bias' towards rural buyers. The rural markets are considered rigid in the nature but it is not the case in real sense. Marketing to rural buyers is not only a challenge to the marketers but to the manufacturers, communicators, national planners and economists as well. Th...

  6. Water repellency diminishes peatland evaporation after wildfire

    Science.gov (United States)

    Kettridge, Nick; Lukenbach, Max; Hokanson, Kelly; Devito, Kevin; Hopkinson, Chris; Petrone, Rich; Mendoza, Carl; Waddington, Mike

    2016-04-01

    Peatlands are a critically important global carbon reserve. There is increasing concern that such ecosystems are vulnerable to projected increases in wildfire severity under a changing climate. Severe fires may exceed peatland ecological resilience resulting in the long term degradation of this carbon store. Evaporation provides the primary mechanisms of water loss from such environments and can regulate the ecological stress in the initial years after wildfire. We examine variations in evaporation within burned peatlands after wildfire through small scale chamber and large scale remote sensing measurements. We show that near-surface water repellency limits peatland evaporation in these initial years post fire. Water repellent peat produced by the fire restricts the supply of water to the surface, reducing evaporation and providing a strong negative feedback to disturbance. This previously unidentified feedback operates at the landscape scale. High surface temperatures that result from large reductions in evaporation within water repellent peat are observed across the 60,000 ha burn scar three months after the wildfire. This promotes high water table positions at a landscape scale which limit the rate of peat decomposition and supports the post fire ecohydrological recovery of the peatlands. However, severe burns are shown to exceed this negative feedback response. Deep burns at the peatland margins remove the hydrophobic layer, increasing post fire evaporation and leaving the peatland vulnerable to drying and associated ecological shifts.

  7. EFFECTS OF MOSQUITO REPELLENTS ON PULMONARY FUNCTIONS

    Directory of Open Access Journals (Sweden)

    Venkatesh

    2014-08-01

    Full Text Available Mosquito bite transmits diseases like Malaria, Filaria, Dengue etc. and usage of repellents is very common and has been in use for a long time. The smoke contains Polyaromatic Hydrocarbons, Aldehydes and Ketones. Review of literature has shown ill effects of this smoke. Hence we intended to study the effect of mosquito repellents on lung functions. This study would be important to create awareness regarding usage of mosquito repellent and to adapt to non-harmful methods of preventing mosquito bites. PFT parameters FVC, FEV1, FEV1/ FVC %, FEF 25-75 and PEFR were recorded in mosquito coil users, liquidator’s users and controls that used neither. It was found that FVC and FEV1 were significantly less in coil and liquidators users compared to controls (P < 0.05. Also it was found that in both coil users and liquidator users FVC, FEV1, FEF 25 -75 and PEFR and showed progressive decline with increased duration of usage (P < 0.05. Hence it was concluded that mosquito coils and liquidators can cause progressive decline in lung functions. Alternative methods to combat mosquito menace, like personal and environmental hygiene and non-chemical methods of protection are therefore recommended.

  8. Nootkatone is a repellent for Formosan subterranean termite (Coptotermes formosanus).

    Science.gov (United States)

    Zhu, B C; Henderson, G; Chen, F; Maistrello, L; Laine, R A

    2001-03-01

    We examined the behavior of Formosan subterranean termites toward one of the components of vetiver grass oil, the roots of which manufacture insect repellents. We found nootkatone, a sesquiterpene ketone, isolated from vetiver oil is a strong repellent and toxicant to Formosan subterranean termites. The lowest effective concentration tested was 10 micrograms/g substrate. This is the first report of nootkatone being a repellent to insects.

  9. Measurements of infiltration and water repellency on different soils

    OpenAIRE

    Lavrač, Rožle

    2012-01-01

    Infiltration is a process of water entering soil from its surface. Field measurements of infiltration are performed with infiltrometers. Calculation of hydraulic conductivity can be done by different equations. Infiltration exhibits large spatial and temporal variability due to many affecting factors. One of those effects is soil water repellency (hydrophobicity). Water-repellent soils do not wet up spontaneously. The intensity and persistence of water repellency vary widely due to variabilit...

  10. Mini Review: Mode of Action of Mosquito Repellents

    Science.gov (United States)

    2013-01-01

    Mini review: Mode of action of mosquito repellents Joseph C. Dickens ⇑, Jonathan D. Bohbot United States Department of Agriculture, Agricultural...Modulation a b s t r a c t The mode of action of mosquito repellents remains a controversial topic. However, electrophysiological studies and molecular...annoyance that can disrupt outdoor activities. The use of repellents decreases contacts between mosquitoes and their hosts, and may even lower the rate of

  11. Engineering Characteristics of Chemically Treated Water-Repellent Kaolin

    OpenAIRE

    Youngmin Choi; Hyunwook Choo; Tae Sup Yun; Changho Lee; Woojin Lee

    2016-01-01

    Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO) ranging from 0.5% to 10%...

  12. Rodent-repellent studies. III. Advanced studies in the evaluation of chemical repellents

    Science.gov (United States)

    Bellack, E.; DeWitt, J.B.

    1949-01-01

    In order to bridge the gap between preliminary screening of chemicals for potential rodent repellency and the application ofthese compounds to paper cartons, more advanced studies in the evaluation ofpromising materials have been carried out. These studies have resulted in: (1) a modification of the food acceptance technique which eliminates doubtful compounds and also provides a closer analogy to the ultimate goal, and (2) a method for rapidly testing chemicals incorporated in paper. When the results of these latter tests are expressed as a function of time, it can be shown that a distinct correlation exists between the deterrency exhibited by treated paper and the repellency of treated food.

  13. Helicopter flights with night-vision goggles: Human factors aspects

    Science.gov (United States)

    Brickner, Michael S.

    1989-01-01

    Night-vision goggles (NVGs) and, in particular, the advanced, helmet-mounted Aviators Night-Vision-Imaging System (ANVIS) allows helicopter pilots to perform low-level flight at night. It consists of light intensifier tubes which amplify low-intensity ambient illumination (star and moon light) and an optical system which together produce a bright image of the scene. However, these NVGs do not turn night into day, and, while they may often provide significant advantages over unaided night flight, they may also result in visual fatigue, high workload, and safety hazards. These problems reflect both system limitations and human-factors issues. A brief description of the technical characteristics of NVGs and of human night-vision capabilities is followed by a description and analysis of specific perceptual problems which occur with the use of NVGs in flight. Some of the issues addressed include: limitations imposed by a restricted field of view; problems related to binocular rivalry; the consequences of inappropriate focusing of the eye; the effects of ambient illumination levels and of various types of terrain on image quality; difficulties in distance and slope estimation; effects of dazzling; and visual fatigue and superimposed symbology. These issues are described and analyzed in terms of their possible consequences on helicopter pilot performance. The additional influence of individual differences among pilots is emphasized. Thermal imaging systems (forward looking infrared (FLIR)) are described briefly and compared to light intensifier systems (NVGs). Many of the phenomena which are described are not readily understood. More research is required to better understand the human-factors problems created by the use of NVGs and other night-vision aids, to enhance system design, and to improve training methods and simulation techniques.

  14. Evaluation of visual acuity with Gen 3 night vision goggles

    Science.gov (United States)

    Bradley, Arthur; Kaiser, Mary K.

    1994-01-01

    Using laboratory simulations, visual performance was measured at luminance and night vision imaging system (NVIS) radiance levels typically encountered in the natural nocturnal environment. Comparisons were made between visual performance with unaided vision and that observed with subjects using image intensification. An Amplified Night Vision Imaging System (ANVIS6) binocular image intensifier was used. Light levels available in the experiments (using video display technology and filters) were matched to those of reflecting objects illuminated by representative night-sky conditions (e.g., full moon, starlight). Results show that as expected, the precipitous decline in foveal acuity experienced with decreasing mesopic luminance levels is effectively shifted to much lower light levels by use of an image intensification system. The benefits of intensification are most pronounced foveally, but still observable at 20 deg eccentricity. Binocularity provides a small improvement in visual acuity under both intensified and unintensified conditions.

  15. Night Sky Brightness at San Pedro Martir Observatory

    Science.gov (United States)

    Plauchu-Frayn, I.; Richer, M. G.; Colorado, E.; Herrera, J.; Córdova, A.; Ceseña, U.; Ávila, F.

    2017-03-01

    We present optical UBVRI zenith night sky brightness measurements collected on 18 nights during 2013 to 2016 and SQM measurements obtained daily over 20 months during 2014 to 2016 at the Observatorio Astronómico Nacional on the Sierra San Pedro Mártir (OAN-SPM) in México. The UBVRI data is based upon CCD images obtained with the 0.84 m and 2.12 m telescopes, while the SQM data is obtained with a high-sensitivity, low-cost photometer. The typical moonless night sky brightness at zenith averaged over the whole period is U = 22.68, B = 23.10, V = 21.84, R = 21.04, I = 19.36, and SQM = 21.88 {mag} {{arcsec}}-2, once corrected for zodiacal light. We find no seasonal variation of the night sky brightness measured with the SQM. The typical night sky brightness values found at OAN-SPM are similar to those reported for other astronomical dark sites at a similar phase of the solar cycle. We find a trend of decreasing night sky brightness with decreasing solar activity during period of the observations. This trend implies that the sky has become darker by Δ U = 0.7, Δ B = 0.5, Δ V = 0.3, Δ R=0.5 mag arcsec‑2 since early 2014 due to the present solar cycle.

  16. Night sky brightness at San Pedro Martir Observatory

    CERN Document Server

    Plauchu-Frayn, I; Colorado, E; Herrera, J; Cordova, A; Cesena, U; Avila, F

    2016-01-01

    We present optical UBVRI zenith night sky brightness measurements collected on eighteen nights during 2013--2016 and SQM measurements obtained daily over twenty months during 2014--2016 at the Observatorio Astronomico Nacional on the Sierra San Pedro Martir (OAN-SPM) in Mexico. The UBVRI data is based upon CCD images obtained with the 0.84m and 2.12m telescopes, while the SQM data is obtained with a high-sensitivity, low-cost photometer. The typical moonless night sky brightness at zenith averaged over the whole period is U = 22.68, B = 23.10, V = 21.84, R = 21.04, I = 19.36, and SQM = 21.88 mag/square arcsec, once corrected for zodiacal light. We find no seasonal variation of the night sky brightness measured with the SQM. The typical night sky brightness values found at OAN-SPM are similar to those reported for other astronomical dark sites at a similar phase of the solar cycle. We find a trend of decreasing night sky brightness with decreasing solar activity during period of the observations. This trend im...

  17. Night blindness and ancient remedy

    Directory of Open Access Journals (Sweden)

    H.A. Hajar Al Binali

    2014-01-01

    Full Text Available The aim of this article is to briefly review the history of night blindness and its treatment from ancient times until the present. The old Egyptians, the Babylonians, the Greeks and the Arabs used animal liver for treatment and successfully cured the disease. The author had the opportunity to observe the application of the old remedy to a patient. Now we know what the ancients did not know, that night blindness is caused by Vitamin A deficiency and the animal liver is the store house for Vitamin A.

  18. Observations on Snake Repellent Property of Some Plant Extracts

    Directory of Open Access Journals (Sweden)

    D.M. Renapurkar

    1991-01-01

    Full Text Available The repellent property of certain plant extracts and oils against snakes has been investigated. For this purpose 15 hexane extracts of plants and 11 oils were tested in the laboratory in a specially designed cage. Out of the materials tested. Across calamus extract and pine oil were found to exhibit excellent snake repellent property.

  19. Multiple activities of insect repellents on odorant receptors in mosquitoes

    Science.gov (United States)

    Several lines of evidence suggest that insect repellent molecules reduce mosquito-host contacts by interacting with odorants and odorant receptors (ORs) ultimately affecting olfactory-driven behaviors. We describe the molecular effects of ten insect repellents and a pyrethroid insecticide with known...

  20. Water repellency of soils; the influence of ambient relative humidity

    NARCIS (Netherlands)

    Doerr, S.H.; Dekker, L.W.; Ritsema, C.J.; Shakesby, R.A.; Bryant, R.

    2002-01-01

    Adverse effects of soil water repellency (hydrophobicity) are of concern during or following rainfall or irrigation, and are often preceded by conditions of high atmospheric relative humidity (RH). Assessments of repellency are, however, commonly conducted on air-dried samples at ambient laboratory

  1. Identification of mosquito repellent odours from Ocimum forskolei.

    Science.gov (United States)

    Dekker, Teun; Ignell, Rickard; Ghebru, Maedot; Glinwood, Robert; Hopkins, Richard

    2011-09-22

    Native mosquito repellent plants have a good potential for integrated mosquito control in local settings. Ocimum forskolei, Lamiaceae, is used in Eritrea as a spatial mosquito repellent inside houses, either through crushing fresh plants or burning dry plants. We verified whether active repellent compounds could be identified using gas-chromatography coupled electroantennogram recordings (GC-EAD) with headspace extracts of crushed plants. EAD active compounds included (R)-(-)-linalool, (S)-(+)-1-octen-3-ol, trans-caryophyllene, naphthalene, methyl salicylate, (R)-(-)-α-copaene, methyl cinnamate and (E)-ocimene. Of these compounds (R)-(-)-linalool, methyl cinnamate and methyl salicylate reduced landing of female Aedes aegypti on human skin-odor baited tubes. The latter two are novel mosquito repellent compounds. The identification of mosquito repellent compounds contributes to deciphering the mechanisms underlying repulsion, supporting the rational design of novel repellents. The three mosquito repellent compounds identified in this study are structurally dissimilar, which may indicate involvement of different sensory neurons in repulsion. Repulsion may well be enhanced through combining different repellent plants (or their synthetic mimics), and can be a locally sustainable part in mosquito control efforts.

  2. Repellent activity of five essential oils against Culex pipiens.

    Science.gov (United States)

    Erler, F; Ulug, I; Yalcinkaya, B

    2006-12-01

    Essential oils extracted from the seeds of anise (Pimpinella anisum), dried fruits of eucalyptus (Eucalyptus camaldulensis), dried foliage of mint (Mentha piperita) and basil (Ocimum basilicum) and fresh foliage of laurel (Laurus nobilis) were tested for their repellency against the adult females of Culex pipiens. All essential oils showed repellency in varying degrees, eucalyptus, basil and anise being the most active.

  3. Novel protein-repellent and biofilm-repellent orthodontic cement containing 2-methacryloyloxyethyl phosphorylcholine.

    Science.gov (United States)

    Zhang, Ning; Zhang, Ke; Melo, Mary Anne S; Chen, Chen; Fouad, Ashraf F; Bai, Yuxing; Xu, Hockin H K

    2016-07-01

    The objectives of this study were to develop the first protein-repellent resin-modified glass ionomer cement (RMGI) by incorporating 2-methacryloyloxyethyl phosphorylcholine (MPC) for orthodontic applications, and to investigate the MPC effects on protein adsorption, biofilm growth, and enamel bond strength. MPC was incorporated into RMGI at 0% (control), 1.5%, 3%, and 5% by mass. Specimens were stored in water at 37°C for 1 and 30 days. Enamel shear bond strength (SBS) was measured, and the adhesive remnant index (ARI) scores were assessed. Protein adsorption onto the specimens was determined by a micro bicinchoninic acid method. A dental plaque microcosm biofilm model with human saliva as inoculum was used. The results showed that adding 3% of MPC into RMGI did not significantly reduce the SBS (p > 0.1). There was no significant loss in SBS for RMGI containing 3% MPC after water-aging for 30 days, as compared to 1 day (p > 0.1). RMGI with 3% MPC had protein adsorption that was 1/10 that of control. RMGI with 3% MPC greatly reduced the bacterial adhesion, and lactic acid production and colony-forming units of biofilms, while substantially increasing the medium solution pH containing biofilms. The protein-repellent and biofilm-repellent effects were not decreased after water-aging for 30 days. In conclusion, the MPC-containing RMGI is promising to reduce biofilms and white spot lesions without compromising orthodontic bracket-enamel bond strength. The novel protein-repellent method may have applicability to other orthodontic cements, dental composites, adhesives, sealants, and cements to repel proteins and biofilms. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 949-959, 2016.

  4. Super toner and ink repellent superoleophobic surface.

    Science.gov (United States)

    Zhao, Hong; Law, Kock-Yee

    2012-08-01

    Offset of imaging material from a fuser surface to paper during fusing is highly undesirable in printing. Here the wetting and repellent characteristics of three imaging materials (a solid wax ink, a waxy polyester toner, and a polyester toner) in their molten states have been studied on three model print surfaces: a transparency (surrogate for paper), a PTFE film, and a model superoleophobic surface, with the aim of assessing their performance in fusing. The superoleophobic surface, with water and hexadecane contact angles of ∼156° and sliding angles at ∼10°, comprises 3 μm diameter pillar arrays on silicon wafer and was fabricated by photolithography followed by surface modification with a fluorosilane. The contact angles of the three imaging materials range from 40 to 79° on the transparency and the sessile drops do not slide even at 90° tilted angle, indicating that they all wet, adhere, and pin on the transparency. Although the contact angles of the three imaging materials are slightly higher (63-85°) on PTFE, the sessile drops do not slide on PTFE either. Because PTFE is widely used as a fuser surface material in combination with different waxy imaging materials commercially, we attribute the successful implementation of PTFE to the use of the wax additive. With the superoleophobic surface, there is a dramatic increase in advancing and static contact angles for all three imaging materials. The advancing and static contact angles are in the 150-168° range for waxy toner, indicative of superhigh repellency. Although the advancing and static contact angles for the polyester toner decrease slightly at 147 and 130°, respectively, the repellency is still very high. More importantly, the sessile drops of all three imaging materials are mobile upon tilting and they all have high receding contact angles. The overall results suggest that the adhesion between the superoleophobic surface and the ink and toner materials are very small relative to those with

  5. Light

    CERN Document Server

    Robertson, William C

    2003-01-01

    Why is left right and right left in the mirror? Baffled by the basics of reflection and refraction? Wondering just how the eye works? If you have trouble teaching concepts about light that you don t fully grasp yourself, get help from a book that s both scientifically accurate and entertaining with Light. By combining clear explanations, clever drawings, and activities that use easy-to-find materials, this book covers what science teachers and parents need to know to teach about light with confidence. It uses ray, wave, and particle models of light to explain the basics of reflection and refraction, optical instruments, polarization of light, and interference and diffraction. There s also an entire chapter on how the eye works. Each chapter ends with a Summary and Applications section that reinforces concepts with everyday examples. Whether you need a deeper understanding of how light bends or a good explanation of why the sky is blue, you ll find Light more illuminating and accessible than a college textbook...

  6. Citrus orchards management and soil water repellency in Eastern Spain

    Science.gov (United States)

    Cerdà, A.; González Peñaloza, F. A.; Jordán, A.; Zavala, L. M.

    2012-04-01

    Water repellent soils are found around the world, although originally was found on fire affected soil (DeBano, 1981). However, for decades, water repellency was found to be a rare soil property. One of the pioneer research that shown that water repellency was a common soil property is the Wander (1949) publication in Science. Wander researched the water repellency on citrus groves, and since then, no information is available about the water repellency on citrus plantations. The Mediterranean soils are prone to water repellency due to the summer dry conditions (Cerdà and Doerr, 2007). And Land Use and Land Management are key factors (Harper et al., 2000; Urbanek et al., 2007) to understand the water repellency behaviour of agriculture soils. Valencia region (Eastern Spain) is the largest exporter in the world and citrus plantations located in the alluvial plains and fluvial terraces are moving to alluvial fans and slopes where the surface wash is very active (Cerdà et al., 2009). This research aims to show the water repellency on citrus orchards located on the sloping terrain (water repellency in citrus orchards under different managements: annual addition of plant residues and manure with no tilling and no fertilizer (MNT), annual addition of plant residues with no tillage (NT), application of conventional herbicides and no tilling (HNT) and conventional tillage in June (CT). The period for each type of management ranged from 2 and 27 (MNT), 1 and 25 (NT), 2 and 27 (HNT) and 3 and 29 years (CT). At each plot, a ten points were selected every 10 cm along inter-rows and water drop penetration time test (WDTP; DeBano, 1981) was performed. The results show that the MNT treatment induced slight water repellency in citrus-cropped soils compared to other treatments. Small but significant soil water repellency was observed under NT and HNT treatments (mean WDTP 4 ± 4 s and 2 ± 2 s, respectively), which may be regarded as subcritical soil water repellency. Slight water

  7. Application of actinomycetes to soil to ameliorate water repellency.

    Science.gov (United States)

    McKenna, F; El-Tarabily, K A; Petrie, S; Chen, C; Dell, B

    2002-01-01

    The aim of this study was to develop a novel isolation technique using a mixture of Bacillus and Streptomyces phages to selectively isolate wax-utilizing non-streptomycete actinomycetes effective in ameliorating water repellency in a problem soil. Phages added to a soil suspension reduced the dominance of Bacillus and Streptomyces isolates and significantly increased the number of non-streptomycete actinomycetes on isolation plates. Promising isolates, grown on a medium containing beeswax as sole carbon source, were selected for application to water repellent soil. Their addition significantly reduced water repellency. Phage application significantly increased the isolation of non-streptomycete actinomycetes. Wax-utilizing isolates were found to significantly reduce water repellency in a problem soil. The phage technique can be used for the routine isolation of non-streptomycete actinomycetes. Beeswax medium can be used to selectively isolate wax-utilizing micro-organisms with the potential to ameliorate water repellency in soil.

  8. Repellents Inhibit P450 Enzymes in Stegomyia (Aedes) aegypti

    Science.gov (United States)

    Jaramillo Ramirez, Gloria Isabel; Logan, James G.; Loza-Reyes, Elisa; Stashenko, Elena; Moores, Graham D.

    2012-01-01

    The primary defence against mosquitoes and other disease vectors is often the application of a repellent. Despite their common use, the mechanism(s) underlying the activity of repellents is not fully understood, with even the mode of action of DEET having been reported to be via different mechanisms; e.g. interference with olfactory receptor neurones or actively detected by olfactory receptor neurones on the antennae or maxillary palps. In this study, we discuss a novel mechanism for repellence, one of P450 inhibition. Thirteen essential oil extracts from Colombian plants were assayed for potency as P450 inhibitors, using a kinetic fluorometric assay, and for repellency using a modified World Health Organisation Pesticide Evaluations Scheme (WHOPES) arm-in cage assay with Stegomyia (Aedes) aegypti mosquitoes. Bootstrap analysis on the inhibition analysis revealed a significant correlation between P450-inhibition and repellent activity of the oils. PMID:23152795

  9. The mysterious multi-modal repellency of DEET

    Science.gov (United States)

    DeGennaro, Matthew

    2015-01-01

    DEET is the most effective insect repellent available and has been widely used for more than half a century. Here, I review what is known about the olfactory and contact mechanisms of DEET repellency. For mosquitoes, DEET has at least two molecular targets: Odorant Receptors (ORs) mediate the effect of DEET at a distance, while unknown chemoreceptors mediate repellency upon contact. Additionally, the ionotropic receptor Ir40a has recently been identified as a putative DEET chemosensor in Drosophila. The mechanism of how DEET manipulates these molecular targets to induce insect avoidance in the vapor phase is also contested. Two hypotheses are the most likely: DEET activates an innate olfactory neural circuit leading to avoidance of hosts (smell and avoid hypothesis) or DEET has no behavioral effect on its own, but instead acts cooperatively with host odors to drive repellency (confusant hypothesis). Resolving this mystery will inform the search for a new generation of insect repellents. PMID:26252744

  10. Repellents inhibit P450 enzymes in Stegomyia (Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Gloria Isabel Jaramillo Ramirez

    Full Text Available The primary defence against mosquitoes and other disease vectors is often the application of a repellent. Despite their common use, the mechanism(s underlying the activity of repellents is not fully understood, with even the mode of action of DEET having been reported to be via different mechanisms; e.g. interference with olfactory receptor neurones or actively detected by olfactory receptor neurones on the antennae or maxillary palps. In this study, we discuss a novel mechanism for repellence, one of P450 inhibition. Thirteen essential oil extracts from Colombian plants were assayed for potency as P450 inhibitors, using a kinetic fluorometric assay, and for repellency using a modified World Health Organisation Pesticide Evaluations Scheme (WHOPES arm-in cage assay with Stegomyia (Aedes aegypti mosquitoes. Bootstrap analysis on the inhibition analysis revealed a significant correlation between P450-inhibition and repellent activity of the oils.

  11. Water repellent soils: the case for unsaturated soil mechanics

    Directory of Open Access Journals (Sweden)

    Beckett Christopher

    2016-01-01

    Full Text Available Water repellent (or “hydrophobic” or “non-wetting” soils have been studied by soil scientists for well over a century. These soils are typified by poor water infiltration, which leads to increased soil erosion and poor crop growth. However, the importance of water repellence on determining soil properties is now becoming recognised by geotechnical engineers. Water repellent soils may, for example, offer novel solutions for the design of cover systems overlying municipal or mine waste storage facilities. However, investigations into factors affecting their mechanical properties have only recently been initiated. This purpose of this paper is to introduce geotechnical engineers to the concept of water repellent soils and to discuss how their properties can be evaluated under an unsaturated soils framework. Scenarios in which water repellent properties might be relevant in geotechnical applications are presented and methods to quantify these properties in the laboratory and in the field examined.

  12. Volunteers for Researchers’ Night wanted

    CERN Multimedia

    Katarina Anthony

    2015-01-01

    Every year, on the last Friday of September, the European Researchers’ Night (see here) takes place in about 300 cities all over Europe - promoting research in engaging and fun ways for the general public. This year, CERN will be participating once again, hosting dozens of events across the Balexert shopping centre – and we’ll need YOUR help to make the celebration a success.   From film screenings and celebrity Q&A sessions to “Ask a Researcher” and build-your-own LEGO LHC events, this year’s Researchers’ Night is going to be jam-packed! The fun will kick off prior to the night itself with a mock-up of the LHC tunnel installed in the central court of the Balexert shopping centre, 8-12 September*. CERN people will be on hand to speak to shoppers about the LHC, and to encourage them to participate in Researchers’ Night! The CERN organisers are recruiting volunteers and support staff for Researchers’ ...

  13. Progress in color night vision

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2012-01-01

    We present an overview of our recent progress and the current state-of-the-art techniques of color image fusion for night vision applications. Inspired by previously developed color opponent fusing schemes, we initially developed a simple pixel-based false color-mapping scheme that yielded fused

  14. Night Operations - The Soviet Approach

    Science.gov (United States)

    1978-06-09

    Battle of Berlin reveal the purpose for the night tactic of il- * ilumination : surprise and psychological impact, both on the enemy and friendly forces. An...attack Ilumination by shell Tn in k* Illumination by flare a Tank In firing position Observation post Antitank missle in firing position APC C3 APC

  15. Progress in color night vision

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2012-01-01

    We present an overview of our recent progress and the current state-of-the-art techniques of color image fusion for night vision applications. Inspired by previously developed color opponent fusing schemes, we initially developed a simple pixel-based false color-mapping scheme that yielded fused fal

  16. Progress in color night vision

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2012-01-01

    We present an overview of our recent progress and the current state-of-the-art techniques of color image fusion for night vision applications. Inspired by previously developed color opponent fusing schemes, we initially developed a simple pixel-based false color-mapping scheme that yielded fused fal

  17. Night blindness and Crohn's disease.

    Science.gov (United States)

    da Rocha Lima, Breno; Pichi, Francesco; Lowder, Careen Y

    2014-10-01

    Signs of malnutrition are common clinical features in Crohn's disease; and bowel resection, commonly needed in these cases, can aggravate malnutrition. These patients are at risk of developing vitamin A deficiency, which can lead to night blindness. We present a 60-year-old male, with history of Crohn's disease and multiple resections for strictures and fistulas leading to short bowel syndrome, with progressive bilateral loss of night vision (nyctalopia). Serum vitamin A level was markedly depleted (11 µg/dL, reference 20-120 µg/dL), and full-field electroretinogram testing demonstrated extinguished scotopic (rod function) responses and decreased amplitudes of photopic responses on 30 Hz flicker (cone function). He was started on vitamin A supplementation (initially intramuscular). His vitamin A level was back to normal (78 µg/dL), and night vision problems subjectively improved. Patients with Crohn's disease should be inquired about night vision problems. The presence of nyctalopia should prompt vitamin A level measurement and ophthalmology referral for further evaluation.

  18. Water repellency induced by pulmonary surfactants.

    Science.gov (United States)

    Hills, B A

    1982-04-01

    1. Pure cotton fabric was partially carboxylated to produce a tough, porous, hydrophilic sub-phase to stimulate the epithelial membrane of the alveolar wall from a permeability standpoint. 2. Two of the predominant pulmonary surfactants, dipalmitoyl lecithin (DPL) and dipalmitoyl phosphatidylethanolamine (DPPE), were found to inhibit wetting of this synthetic membrane and of human cutaneous epithelium as manifest by a large contact angle. 3. When treated with DPL at physiological concentrations, the porous synthetic membrane was found to support a head of saline well in excess of systolic pulmonary artery pressure with no penetration and could do so for periods well in excess of 1 hr; untreated control samples allowed almost immediate fluid filtration. 4. Filtration could be initiated in the DPL-treated membranes by wetting the reverse side, confirming that the threshold pressure for fluid penetration was afforded by capillarity and, hence, by water repellency induced by the surfactant. 5. Water repellency induced by the amphoteric surfactants occurring naturally in the lung is discussed as a possible factor contributing to the pressure threshold to be exceeded for alveolar oedema to form. 6. Evidence is reviewed and several advantages discussed for the implied concept of an essentially dry lining to the alveolus with a discontinuous liquid layer largely confined to convex corners which could slowly resolve any oedema by surface forces.

  19. Field evaluation of picaridin repellents reveals differences in repellent sensitivity between Southeast Asian vectors of malaria and arboviruses.

    Directory of Open Access Journals (Sweden)

    Karel Van Roey

    2014-12-01

    Full Text Available Scaling up of insecticide treated nets has contributed to a substantial malaria decline. However, some malaria vectors, and most arbovirus vectors, bite outdoors and in the early evening. Therefore, topically applied insect repellents may provide crucial additional protection against mosquito-borne pathogens. Among topical repellents, DEET is the most commonly used, followed by others such as picaridin. The protective efficacy of two formulated picaridin repellents against mosquito bites, including arbovirus and malaria vectors, was evaluated in a field study in Cambodia. Over a period of two years, human landing collections were performed on repellent treated persons, with rotation to account for the effect of collection place, time and individual collector. Based on a total of 4996 mosquitoes collected on negative control persons, the overall five hour protection rate was 97.4% [95%CI: 97.1-97.8%], not decreasing over time. Picaridin 20% performed equally well as DEET 20% and better than picaridin 10%. Repellents performed better against Mansonia and Culex spp. as compared to aedines and anophelines. A lower performance was observed against Aedes albopictus as compared to Aedes aegypti, and against Anopheles barbirostris as compared to several vector species. Parity rates were higher in vectors collected on repellent treated person as compared to control persons. As such, field evaluation shows that repellents can provide additional personal protection against early and outdoor biting malaria and arbovirus vectors, with excellent protection up to five hours after application. The heterogeneity in repellent sensitivity between mosquito genera and vector species could however impact the efficacy of repellents in public health programs. Considering its excellent performance and potential to protect against early and outdoor biting vectors, as well as its higher acceptability as compared to DEET, picaridin is an appropriate product to evaluate the

  20. Field evaluation of picaridin repellents reveals differences in repellent sensitivity between Southeast Asian vectors of malaria and arboviruses.

    Science.gov (United States)

    Van Roey, Karel; Sokny, Mao; Denis, Leen; Van den Broeck, Nick; Heng, Somony; Siv, Sovannaroth; Sluydts, Vincent; Sochantha, Tho; Coosemans, Marc; Durnez, Lies

    2014-12-01

    Scaling up of insecticide treated nets has contributed to a substantial malaria decline. However, some malaria vectors, and most arbovirus vectors, bite outdoors and in the early evening. Therefore, topically applied insect repellents may provide crucial additional protection against mosquito-borne pathogens. Among topical repellents, DEET is the most commonly used, followed by others such as picaridin. The protective efficacy of two formulated picaridin repellents against mosquito bites, including arbovirus and malaria vectors, was evaluated in a field study in Cambodia. Over a period of two years, human landing collections were performed on repellent treated persons, with rotation to account for the effect of collection place, time and individual collector. Based on a total of 4996 mosquitoes collected on negative control persons, the overall five hour protection rate was 97.4% [95%CI: 97.1-97.8%], not decreasing over time. Picaridin 20% performed equally well as DEET 20% and better than picaridin 10%. Repellents performed better against Mansonia and Culex spp. as compared to aedines and anophelines. A lower performance was observed against Aedes albopictus as compared to Aedes aegypti, and against Anopheles barbirostris as compared to several vector species. Parity rates were higher in vectors collected on repellent treated person as compared to control persons. As such, field evaluation shows that repellents can provide additional personal protection against early and outdoor biting malaria and arbovirus vectors, with excellent protection up to five hours after application. The heterogeneity in repellent sensitivity between mosquito genera and vector species could however impact the efficacy of repellents in public health programs. Considering its excellent performance and potential to protect against early and outdoor biting vectors, as well as its higher acceptability as compared to DEET, picaridin is an appropriate product to evaluate the epidemiological

  1. Pore-scale distribution of mucilage affecting water repellency in the rhizosphere

    Science.gov (United States)

    Benard, Pascal; Zarebanadkouki, Mohsen; Hedwig, Clemens; Holz, Maire; Ahmed, Mutez; Carminati, Andrea

    2017-04-01

    The hydraulic properties of the rhizosphere are altered by plants, fungi and microorganism. Plant roots release different compounds into the soil. One of these substances is mucilage, a gel which turns water repellent upon drying. We introduce a conceptual model of mucilage deposition during soil drying and its impact on the soil wettability. As the soil dries, water menisci recede and draw mucilage towards the contact region between particles where it is deposited. At high mucilage content, mucilage deposits expand into the open pore space and finally block water infiltration when a critical fraction of the pore space is blocked. To test this hypothesis, we mixed mucilage and particles of different grain size, we let them dry and measured the contact angle using the sessile drop method. Mucilage deposition was visualized by light microscopy imaging. Contact angle measurements showed a distinct threshold-like behavior with a sudden increase in apparent contact angle at high mucilage concentrations. Particle roughness induced a more uniform distribution of mucilage. The observed threshold corresponds to the concentration when mucilage deposition occupies a critical fraction of the pore space, as visualized with the microscope images. In conclusion, water repellency is critically affected by the distribution of mucilage on the pore-scale. This microscopic heterogeneity has to be taken into account in the description of macroscopic processes, like water infiltration or rewetting of water repellent soil.

  2. Quantitative assessment to the structural basis of water repellency in natural and technical surfaces.

    Science.gov (United States)

    Wagner, P; Fürstner, R; Barthlott, W; Neinhuis, C

    2003-04-01

    Many plant surfaces are water-repellent because of a complex 3-dimensional microstructure of the epidermal cells (papillae) and a superimposed layer of hydrophobic wax crystals. Due to its surface tension, water does not spread on such surfaces but forms spherical droplets that lie only on the tips of the microstructures. Studying six species with heavily microstructured surfaces by a new type of confocal light microscopy, the number, height, and average distance of papillae per unit area were measured. These measurements were combined with those of an atomic force microscope which was used to measure the exposed area of the fine-structure on individual papillae. According to calculations based upon these measurements, roughening results in a reduction of the contact area of more than 95% compared with the projected area of a water droplet. By applying water/methanol solutions of decreasing surface tension to a selection of 33 water-repellent species showing different types of surface structures, the critical value at which wetting occurs was determined. The results impressively demonstrated the importance of roughening on different length scales for water-repellency, since extremely papillose surfaces, having an additional wax layer, are able to resist up to 70% methanol. Surfaces that lack papillae or similar structures on the same length scale are much more easily wetted.

  3. Design Considerations For Night Vision Goggles

    Science.gov (United States)

    Glasheen, W. M.; Reiss, R. S.

    1985-01-01

    Baird Corporation of Bedford, Massachusetts, has designed and developed two similar night vision goggles. These goggles are binocular viewing to the wearer's eyes, but use a single objective lens and a single image intensifier tube. Binocular viewing is achieved by dividing a single image and sharing it between the'viewer's eyes. The goggles are self-sufficient, independent instruments which can be simply and easily interfaced with a face mask that the viewer wears. This paper covers the main design considerations that are associated with achieving the goals of these goggle configurations and their performance. Baird's first goggle design is designated the GP/NVG; the second is designated the AN/PVS-7. The GP/NVG night vision goggle is a high-performance, single intensifier tube, passive night vision device that provides the user with a 40-degree field of view at unity magnification. The fixed aperture, f/1.0 objective lens collects the available light and images it on the fiber optic faceplate of the second generation image intensifier tube. The image intensifier tube converts the real image at the fiber optic faceplate into electrons across the image, amplifies them, and then reconverts the electrons into a real, visible image at the fiber optic output of the tube. This image is then collimated to appear as if it is coming from infinity, split in two, and reimaged by the relay lenses. The eyelenses provide a magnified image to the user. The user can adjust each eyelens to clearly view the output faceplate of the image intensifier tube. This adjustment is made only once for each user. The objective focus can be manually set for distances from 25 centimeters to infinity. The general configuration of this night vision goggle is similar to that of a pair of single objective binocular field glasses. It is extremely lightweight (with most of the main construction molded from plastic) and compact for easy handling. All adjustments and on/off switching have been "human

  4. Soil water repellency in north-eastern Greece with adverse effects of drying on the persistence

    NARCIS (Netherlands)

    Ziogas, A.K.; Dekker, L.W.; Oostindie, K.; Ritsema, C.J.

    2005-01-01

    Many soils may be water repellent to some degree, challenging the common perception that soil water repellency is only an interesting aberration. When dry, water repellent soils resist or retard water infiltration into the soil matrix. Soil water repellency often leads to the development of unstable

  5. Soil water repellency in north-eastern Greece with adverse effects of drying on the persistence

    NARCIS (Netherlands)

    Ziogas, A.K.; Dekker, L.W.; Oostindie, K.; Ritsema, C.J.

    2005-01-01

    Many soils may be water repellent to some degree, challenging the common perception that soil water repellency is only an interesting aberration. When dry, water repellent soils resist or retard water infiltration into the soil matrix. Soil water repellency often leads to the development of unstable

  6. Correlation between chemical structure and rodent repellency of benzoic acid derivatives

    Science.gov (United States)

    Fearn, J.E.; DeWitt, J.B.

    1965-01-01

    Sixty-five benzoic acid derivatives were either prepared or obtained from commercial concerns, tested for rat repellency, and their indices of repellency computed. The data from these tests were considered analytically for any correlation between chemical structure and rat repellency. The results suggest a qualitative relationship which is useful in deciding probability of repellency in other compounds.

  7. Light

    CERN Document Server

    Ditchburn, R W

    2011-01-01

    This classic study, available for the first time in paperback, clearly demonstrates how quantum theory is a natural development of wave theory, and how these two theories, once thought to be irreconcilable, together comprise a single valid theory of light. Aimed at students with an intermediate-level knowledge of physics, the book first offers a historical introduction to the subject, then covers topics such as wave theory, interference, diffraction, Huygens' Principle, Fermat's Principle, and the accuracy of optical measurements. Additional topics include the velocity of light, relativistic o

  8. Low Cost Night Vision System for Intruder Detection

    Science.gov (United States)

    Ng, Liang S.; Yusoff, Wan Azhar Wan; R, Dhinesh; Sak, J. S.

    2016-02-01

    The growth in production of Android devices has resulted in greater functionalities as well as lower costs. This has made previously more expensive systems such as night vision affordable for more businesses and end users. We designed and implemented robust and low cost night vision systems based on red-green-blue (RGB) colour histogram for a static camera as well as a camera on an unmanned aerial vehicle (UAV), using OpenCV library on Intel compatible notebook computers, running Ubuntu Linux operating system, with less than 8GB of RAM. They were tested against human intruders under low light conditions (indoor, outdoor, night time) and were shown to have successfully detected the intruders.

  9. Bioluminescence as an ecological factor during high Arctic polar night

    Science.gov (United States)

    Cronin, Heather A.; Cohen, Jonathan H.; Berge, Jørgen; Johnsen, Geir; Moline, Mark A.

    2016-11-01

    Bioluminescence commonly influences pelagic trophic interactions at mesopelagic depths. Here we characterize a vertical gradient in structure of a generally low species diversity bioluminescent community at shallower epipelagic depths during the polar night period in a high Arctic fjord with in situ bathyphotometric sampling. Bioluminescence potential of the community increased with depth to a peak at 80 m. Community composition changed over this range, with an ecotone at 20–40 m where a dinoflagellate-dominated community transitioned to dominance by the copepod Metridia longa. Coincident at this depth was bioluminescence exceeding atmospheric light in the ambient pelagic photon budget, which we term the bioluminescence compensation depth. Collectively, we show a winter bioluminescent community in the high Arctic with vertical structure linked to attenuation of atmospheric light, which has the potential to influence pelagic ecology during the light-limited polar night.

  10. Engineering water repellency in granular materials for ground applications

    Science.gov (United States)

    Lourenco, Sergio; Saulick, Yunesh; Zheng, Shuang; Kang, Hengyi; Liu, Deyun; Lin, Hongjie

    2017-04-01

    Synthetic water repellent granular materials are a novel technology for constructing water-tight barriers and fills that is both inexpensive and reliant on an abundant local resource - soils. Our research is verifying its stability, so that perceived risks to practical implementation are identified and alleviated. Current ground stabilization measures are intrusive and use concrete, steel, and glass fibres as reinforcement elements (e.g. soil nails), so more sustainable approaches that require fewer raw materials are strongly recommended. Synthetic water repellent granular materials, with persistent water repellency, have been tested for water harvesting and proposed as landfill and slope covers. By chemically, physically and biologically adjusting the magnitude of water repellency, they offer the unique advantage of controlling water infiltration and allow their deployment as semi-permeable or impermeable materials. Other advantages include (1) volumetric stability, (2) high air permeability and low water permeability, (3) suitability for flexible applications (permanent and temporary usage), (4) improved adhesion aggregate-bitumen in pavements. Application areas include hydraulic barriers (e.g. for engineered slopes and waste containment), pavements and other waterproofing systems. Chemical treatments to achieve water repellency include the use of waxes, oils and silicone polymers which affect the soil particles at sub-millimetric scales. To date, our research has been aimed at demonstrating their use as slope covers and establishing the chemical compounds that develop high and stable water repellency. Future work will determine the durability of the water repellent coatings and the mechanics and modelling of processes in such soils.

  11. Coloring night vision imagery for depth perception

    Institute of Scientific and Technical Information of China (English)

    Xiaojing Gu; Shaoyuan Sun; Jian'an Fang

    2009-01-01

    Depth perception for night vision(NV)imagery could largely improve scene comprehension.We present a novel scheme to give fused multi-band NV imagery smoothly natural color appearance as well as depth sense from color.Our approach is based on simulating color cues by varying saturation values of each object in the color NV image,in correspondence with the ratio between the infrared and low-light-level sensor outputs which in practice is the depth feature for same materials.We render the NV image segment-by-segment by taking advantage of image segmentation,dominant color transfer,saturation variation,and image fusion.Experiments have shown that the proposed scheme can achieve satisfying results.

  12. Arabian sandflies (Diptera: Psychodidae) prefer the hottest nights?

    Science.gov (United States)

    Roberts, D M

    1994-04-01

    A vehicle-mounted net was used to collect hourly samples of sandflies on 15 nights during June in northern Oman. Every half hour, the temperature, relative humidity, wind velocity and light intensity were measured (there was no cloud or rainfall during this period). The sandflies caught were mainly Phlebotomus alexandri and Sergentomyia clydei. Their circadian activity increased rapidly after sunset (18.50 hours). The high level of activity was fairly constant during 9h of darkness until dawn, when it decreased rapidly. A few flies were still active at 07.00 hours, 1.5h after sunrise. A multiple regression showed that the main factor affecting sandfly activity was light intensity. When this factor was removed, by considering only the 135 catches collected during the 9h of darkness, the second most important factor was low relative humidity, followed by low wind velocity. Temperature was not a significant factor in the analysis, because of its strong negative correlation with humidity. However, when the effect of humidity was removed from the regression, high temperature became significant, but less important than wind. The regressions showed that, for flight activity, the optimum humidity was around 10%; the probable maximum wind velocity was 3.5 m s-1 and 11 degrees C was the probable minimum temperature. Thus, when the 4 nights with highest catches (200-260 flies/night) were compared with the 4 nights with lowest catches (50-120 flies/night), the best nights had a low humidity (10-25%) and low wind speed (temperatures (31-43 degrees C).

  13. Night Vision Device and Cockpit Displays

    Data.gov (United States)

    Federal Laboratory Consortium — The Night Vision Device and Cockpit Display labevaluates night vision devices and certifies them for use in the fleet. Lab functions supported include: Analysis of...

  14. Performance of the plant-based repellent TT-4302 against mosquitoes in the laboratory and field and comparative efficacy to 16 mosquito repellents against Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Bissinger, B W; Schmidt, J P; Owens, J J; Mitchell, S M; Kennedy, M K

    2014-03-01

    Repellent efficacy of the plant-based repellent, TT-4302 (5% geraniol), was compared with 16 other products in laboratory arm-in-cage trials against Aedes aegypti (L). Eight repellents (Badger, BioUD, Burt's bees, California Baby, Cutter Natural, EcoSMART, Herbal Armor, and SkinSmart) exhibited a mean repellency below 90% to Ae. aegypti at 0.5 h after application. Three repellents (Buzz Away Extreme, Cutter Advanced, and OFF! Botanicals lotion) fell below 90% repellency 1.5 h after application. TT-4302 exhibited 94.7% repellency 5 h posttreatment, which was a longer duration than any of the other repellents tested. The positive control, 15% DEET (OFF! Active), was repellent for 3 h before activity dropped below 90%. Additional arm-in-cage trials comparing TT-4302 with 15% DEET were carried out against Anopheles quadrimaculatus Say. At 6 h after treatment, TT-4302 provided 95.2% repellency while DEET exhibited 72.2%. In North Carolina field trials, TT-4302 provided 100% repellency 5 h after application against Aedes albopictus Skuse while DEET provided 77.6% repellency. These results demonstrate that TT-4302 is an efficacious plant-based repellent that provides an extended duration of protection compared with many other commercially available products.

  15. Nectar Theft and Floral Ant-Repellence: A Link between Nectar Volume and Ant-Repellent Traits?

    Science.gov (United States)

    Ballantyne, Gavin; Willmer, Pat

    2012-01-01

    As flower visitors, ants rarely benefit a plant. They are poor pollinators, and can also disrupt pollination by deterring other flower visitors, or by stealing nectar. Some plant species therefore possess floral ant-repelling traits. But why do particular species have such traits when others do not? In a dry forest in Costa Rica, of 49 plant species around a third were ant-repellent at very close proximity to a common generalist ant species, usually via repellent pollen. Repellence was positively correlated with the presence of large nectar volumes. Repellent traits affected ant species differently, some influencing the behaviour of just a few species and others producing more generalised ant-repellence. Our results suggest that ant-repellent floral traits may often not be pleiotropic, but instead could have been selected for as a defence against ant thieves in plant species that invest in large volumes of nectar. This conclusion highlights to the importance of research into the cost of nectar production in future studies into ant-flower interactions. PMID:22952793

  16. 蚊虫驱避剂的驱避机理研究%Repelling mechanism of mosquitoes repellent

    Institute of Scientific and Technical Information of China (English)

    廖圣良; 姜志宽; 宋杰; 王宗德; 韩招久; 陈金珠

    2012-01-01

    A review about the research of repelling mechanism is presented.Two mainstream hypotheses possible repelling mechanisms have been proposed:repellent interferes with the mosquitoes olfactory system to block the recognition of the host odor,therefore,mosquitoes can' t detect the existance of the host ; or mosquitoes evade host after its olfactory neuron is activated by repellent.Some research relating repellent in the author(s) laboratory was introduced as well,especially the investigation on repelling mechanism from the perspective of association between repellent and attractant.%本文就蚊虫驱避机理的研究进行了综述,详细介绍了目前两类主流的驱避机理假说:驱避剂干扰嗅觉系统以阻断蚊虫对宿主气味的识别、驱避剂激活嗅觉神经元引起蚊虫的主动躲避行为.介绍了笔者所在实验室近几年对驱避剂进行的相关研究,以及从驱避剂与引诱剂缔合作用的角度对驱避机理的研究.

  17. Essential Oil Repellents- A short Review

    Directory of Open Access Journals (Sweden)

    R V GEETHA

    2014-06-01

    Full Text Available Mosquitoes are the most important of insects in terms of public health importance which transmit a number of diseases such as dengue, chikungunya, Japanese B encephalitis, filariasis and malaria, causing millions of deaths every year. Mosquito control and personal protection from mosquito bites are currently the most important measures to prevent these diseases. Essential oils from plants have been recognized as important natural resources of insecticides because some are selective, biodegrade to non-toxic products and have few effects on non-target organisms and environment. Essential oils are volatile mixtures of hydrocarbons with a diversity of functional groups, and their repellent activity has been linked to the presence of mono - terpenes and sesquiterpenes. In some cases, these chemicals can work synergistically, improving their effectiveness. The aim of this review is to highlight the significance of essential oil from Cymbopogon winterianus Jowitt, Azadirchata indica, Lavandula angustifolia, Mentha piperita for control of vector- borne disease

  18. Pest repellent properties of ant pheromones

    DEFF Research Database (Denmark)

    Offenberg, Joachim

    2012-01-01

    Many ant species are efficient control agents against a wide range of pest insects in many crops. They control pest insects via predation; however, ant communication is based on chemical cues which may be eavesdropped by potential prey and serve as chemical warning signals. Thus, the presence...... of ant pheromones may be sufficient to repel pest insects from ant territories. The study of ant semiochemicals is in its infancy, yet, evidence for their potential use in pest management is starting to build up. Pheromones from four of five tested ant species have been shown to deter herbivorous insect...... prey and competing ant species are also deterred by ant deposits, whereas ant symbionts may be attracted to them. Based on these promising initial findings, it seems advisable to further elucidate the signaling properties of ant pheromones and to test and develop their use in future pest management....

  19. Using Repellent Products to Protect against Mosquito-Borne Illnesses

    Science.gov (United States)

    ... Us Share Using Repellent Products to Protect against Mosquito-Borne Illnesses More Information CDC-Avoid Mosquito Bites ... safety precautions . Top of Page Finding EPA-Registered Mosquito Adulticides and Larvicides The National Pesticide Information Center's ...

  20. Prevention of vector transmitted diseases with clove oil insect repellent.

    Science.gov (United States)

    Shapiro, Rochel

    2012-08-01

    Vector repellent is one element in the prevention of vector-borne diseases. Families that neglect protecting their children against vectors risk their children contracting illnesses such as West Nile virus, eastern equine encephalitis, Lyme disease, malaria, dengue hemorrhagic fever, yellow fever, babesiosis, Crimean-Congo hemorrhagic fever, Rocky Mountain spotted fever, Southern tick-associated rash illness, ehrlichiosis, tick-borne relapsing fever, tularemia, and other insect and arthropod related diseases (CDC, 2011). Identification of families at risk includes screening of the underlying basis for reluctance to apply insect repellent. Nurses and physicians can participate in a positive role by assisting families to determine the proper prophylaxis by recommending insect repellent choices that are economical, safe, and easy to use. A holistic alternative might include the suggestion of clove oil in cases where families might have trepidations regarding the use of DEET on children. This article will explore the safety and effectiveness of clove oil and its use as an insect repellent.

  1. Comparative repellency of 38 essential oils against mosquito bites.

    Science.gov (United States)

    Trongtokit, Yuwadee; Rongsriyam, Yupha; Komalamisra, Narumon; Apiwathnasorn, Chamnarn

    2005-04-01

    The mosquito repellent activity of 38 essential oils from plants at three concentrations was screened against the mosquito Aedes aegypti under laboratory conditions using human subjects. On a volunteer's forearm, 0.1 mL of oil was applied per 30 cm2 of exposed skin. When the tested oils were applied at a 10% or 50% concentration, none of them prevented mosquito bites for as long as 2 h, but the undiluted oils of Cymbopogon nardus (citronella), Pogostemon cablin (patchuli), Syzygium aromaticum (clove) and Zanthoxylum limonella (Thai name: makaen) were the most effective and provided 2 h of complete repellency. From these initial results, three concentrations (10%, 50% and undiluted) of citronella, patchouli, clove and makaen were selected for repellency tests against Culex quinquefasciatus and Anopheles dirus. As expected, the undiluted oil showed the highest protection in each case. Clove oil gave the longest duration of 100% repellency (2-4 h) against all three species of mosquito.

  2. Relative efficacy of various oils in repelling mosquitoes.

    Science.gov (United States)

    Ansari, M A; Razdan, R K

    1995-09-01

    Field studies were carried out to determine the relative efficacy of repellant action of vegetable, essential and chemical base oils against vector mosquitoes. Results revealed that essential oils viz. Cymbopogan martinii martinii var. Sofia (palmarosa), Cymbopogan citratus (lemon grass) and Cymbopogan nardus (citronella) oils are as effective as chemical base oil namely mylol. These oils provide almost complete protection against Anopheles culicifacies and other anopheline species. Per cent protection against Culex quinquefasciatus ranged between 95-96%. Camphor (C. camphora) oil also showed repellent action and provided 97.6% protection against An. culicifacies and 80.7% against Cx. quinquefasciatus. Vegetable oils namely mustard (B. compestris) and coconut (C. nucisera) showed repellent action, however the efficacy of these oils was not much pronounced against Cx. quinquefasciatus. Results of statistical analysis revealed significant difference between vegetable and essential oils (p mosquitoes. Essential oils were found marginally superior in repellancy than camphor and mylol (p < 0.01) against An. culicifacies and Cx. quinquefasciatus.

  3. Surface Treatment of Building Materials with Water Repellent Agents

    OpenAIRE

    Wittman, F.H.; Siemes, T.A.J.M.; Verhoef, L.G.W.

    1995-01-01

    Water repellent agents have been applied to proteet building materials and structural elements for thousands ofyears. Initially, natural products, such as oils and fats were used exclusively. More recently, synthetic organic compounds are being developed for special applications.

  4. A Water-repellent Silanization Coating Technique for MEMS

    Science.gov (United States)

    Shimaoka, Keiichi; Hosokawa, Hideki; Funabashi, Hirohumi; Mitsushima, Yasuichi

    A gas-phase water-repellent silanization coating technique, which prevents the microscopic structures used for micro-sensors and micro-electro-mechanical systems (MEMS) from sticking to the silicon substrates and other microscopic structures during operation, have been developed. Use of a water-repellent coating is one method that prevents sticking by reducing the surface energy of the structure. The water-repellency characteristics of three types of organosilicon compounds were evaluated. It was found that a water-repellent silanization coating layer using (tridecafluoro - 1, 1, 2, 2 -tetrahydrooctyl) trichlorosilane (C8H4Cl3F13Si) had most excellent durability. It was confirmed that the water contact angle of C8H4Cl3F13Si coating layer is exceeding 90 degrees at surface of standard semiconductor materials except nickel. In addition, the C8H4Cl3F13Si coating layer can be patterned by ultraviolet irradiation.

  5. Microencapsulated citronella oil for mosquito repellent finishing of cotton textiles.

    Science.gov (United States)

    Specos, M M Miró; García, J J; Tornesello, J; Marino, P; Vecchia, M Della; Tesoriero, M V Defain; Hermida, L G

    2010-10-01

    Microcapsules containing citronella essential oil were prepared by complex coacervation and applied to cotton textiles in order to study the repellent efficacy of the obtained fabrics. Citronella released from treated textiles was indirectly monitored by the extractable content of its main components. Repellent activity was assessed by exposure of a human hand and arm covered with the treated textiles to Aedes aegypti mosquitoes. Fabrics treated with microencapsulated citronella presented a higher and longer lasting protection from insects compared to fabrics sprayed with an ethanol solution of the essential oil, assuring a repellent effect higher than 90% for three weeks. Complex coacervation is a simple, low cost, scalable and reproducible method of obtaining encapsulated essential oils for textile application. Repellent textiles were achieved by padding cotton fabrics with microcapsules slurries using a conventional pad-dry method. This methodology requires no additional investment for textile finishing industries, which is a desirable factor in developing countries.

  6. Evaluation of the Repellent and Insecticidal Activities of the Leaf ...

    African Journals Online (AJOL)

    ADOWIE PERE

    high repellent and insecticidal activities demonstrated by the root powder ... generally low as a result of serious insect pest attacks ..... to have clear insecticidal properties (DeGeyter, 2012) ... nematicidal ingredients from neem leaves, siam.

  7. Mitigation of water repellency in burned soils applying hydrophillic polymers

    Science.gov (United States)

    Neris, Jonay; de la Torre, Sara; Vidal-Vazquez, Eva; Lado, Marcos

    2017-04-01

    In this study, the effect of fire on water repellency was analyzed in soils from different parent materials, as well as the suitability of anionic polyacrylamide (PAM) to reduce water repellency in these soils. Samples were collected in four different sites where wildfires took place: two in the Canary Islands, with soils developed on volcanic materials, and two in Galicia (NW Spain), with soils developed on plutonic rocks. In Galicia, two soil samples were collected in each site, one in the burnt area and one in an adjacent unburnt area. In the Canary Islands, four samples were collected from each site, three inside the burnt area where the soils were affected by different fire intensities, and one in an unburnt adjacent area. Samples were air-dried and sieved by a 2-mm mesh sieve. Water repellency was measured using the Water Drop Penetration Time test. An amount of 10 g of soil was placed in a tray. Five drops of deionized water were place on the soil surface with a pipette, and the time for each drop to fully penetrate into the soil was recorded. PAM solution was applied to the burnt soils simulating a field application rate of 1gm-2. The polymer used was Superfloc A-110 (Kemira Water Solutions BV, Holland) with 1x107 Da molecular weigth and 15% hydrolysis. PAM was sprayed on the soil surface as solution with a concentration 0.2 g/L. After the application, the samples were dried and the WDPT test was performed. Three replicates for each treatment and soil were used, and the treatments included: dry soil, dry soil after a wetting treatment, dry PAM-treated soil. The results showed that water repellency was modified by fire differently in the various soils. In hydrophilic soils and soils with low water repellency, water repellency was increased after the action of fire. In soils with noticeable initial water repellency, this was reduced or eliminated after the fire. Wetting repellent soils caused a decrease in water repellency most probably because of the spatial

  8. Green lights

    DEFF Research Database (Denmark)

    Fisker, Peter Kielberg

    This study investigates the effect of drought on economic activity globally using remote sensing data. In particular, predicted variation in greenness is correlated with changes in the density of artificial light observed at night on a grid of 0.25 degree latitude-longitude pixels. I define drought...

  9. GLOBE at Night: Scientific Research outside of the Classroom

    Science.gov (United States)

    Henderson, S.; Walker, C. E.; Geary, E.; Pompea, S. M.

    2005-12-01

    participated in GLOBE workshops resulting in over 13 million environmental measurements reported by students to the GLOBE Web site. GLOBE at Night will utilize the GLOBE infrastructure and network to promote a week of night observations (February 2006) by teachers and students. The quality of the night sky for stellar observations is impacted by several factors, including human influences. GLOBE at Night will help scientists assess how the quality of the night sky varies around the world. The data that is collected will be accessible via the GLOBE Web site by scientists studying light pollution and will be available for use by teachers and students worldwide. GLOBE at Night is a collaborative effort of the NASA-sponsored GLOBE Program and the National Optical Astronomy Observatory (NOAO).

  10. A repellent for protecting corn seed from blackbirds and crows

    Science.gov (United States)

    Stickley, A.R.; Guarineo, J.L.

    1972-01-01

    Methiocarb [4-(methylthio)-3,-5-xylyl N-methylcarbamate] was tested as a seed treatment for repelling blackbirds and crows (Corvus sp.) from sprouting corn in South Carolina. The test was conducted on eight fields within a 0.25-square-mile area. Marked repellency occurred; sprout damage averaged 44 percent in the control fields and 0.3 percent in the fields treated with methiocarb.

  11. Strange Quasi-Repeller in a Kicked Rotor

    Institute of Scientific and Technical Information of China (English)

    姜玉梅; 何大韧

    2003-01-01

    A new kind of crisis was observed in a system where a transition from conservative toquasi-dissipative can be observed. The crisis signifies a sudden and intrinsic change of a stochasticweb, which is formed by the end-results of the images of the discontinuous borderlines of the systemfunction. In the crisis, a strange quasi-repeller can be defined. When changing the controllingparameter, the variation of the fractile dimension of the quasi-repeller obeys a logarithmic rule.

  12. Measurements of water repellency and infiltration of the soil

    OpenAIRE

    Žnidaršič, Petra

    2013-01-01

    Soil water repellency is a reduction in the rate of wetting caused by the presence of hydrophobic coatings on soil particles. The occurrence of the absorption of water from the surface of the ground in its interior is called infiltration. Water resistance and infiltration are dependent on a number of influences. All measurements were done on three different soil types at each at the ground level and in the trench. Water repellency measurements were performed by two methods, namely with wat...

  13. REPELLERS FOR MULTIFUNCTIONS OF SEMI-BORNOLOGICAL SPACES

    Institute of Scientific and Technical Information of China (English)

    M.R. Molaei; T. Waezizadeh

    2008-01-01

    In this article the notion of repeller for multifunctions from the viewpoints of semi-bornological spaces is considered. The concept of lower semi-continuous multifunc-tions is extended by the use of semi-bornological spaces. Semi-bornological vector spaces are studied. The notion of conjugacy for semi-bornological multifunctions is considered. The persistence of repeller under conjugate relation is proved.

  14. DEET Insect Repellent: Effects on Thermoregulatory Sweating and Physiological Strain

    Science.gov (United States)

    2011-01-01

    standard skin repellent, as it is effective against a wide variety of disease-transmitting insects, including mosquitoes, flies, fleas , ticks and chigger...evaporation, thus impeding evaporative heat loss. To our knowledge, only one study has experimentally examined the impact of an insect repellent on...body fat was then calculated using the Siri equation (1993). During heat acclimation and all experimental testing sessions, heart rate (HR) was

  15. Insect Repellents: Modulators of Mosquito Odorant Receptor Activity

    Science.gov (United States)

    2010-08-01

    products include the active ingredients N,N- diethyl -3-methylbenzamide (DEET), Insect Repellent 3535 (IR3535), and more recently Picaridin and 2...than the odorant. DEET and indole share an aromatic ring and a nitrogen-linked function. 2-U and octenol share a similar carbon backbone, and 2-U has a...effects of all four repellents were reversible upon fresh exposure to the odorant alone, suggesting that the interaction between the inhibitors and the ORs

  16. popscience - European Researchers Night 2014

    CERN Multimedia

    Jeanneret, Guillaume

    2014-01-01

    Vendredi 26 septembre 2014, le CERN célèbrera la Nuit européenne des chercheurs à Genève et à St-Genis-Pouilly. Le thème de l’édition 2014 est inspiré d’Andy Warhol : « Pop science is for everyone ». On Friday 26 September 2014, CERN will be celebrating European Researchers' Night at three venues in Geneva and St. Genis-Pouilly. Inspired by Andy Warhol, this year's theme is “Pop science is for everyone”.

  17. Sleep, ageing and night work

    Directory of Open Access Journals (Sweden)

    M.L.N. Pires

    2009-09-01

    Full Text Available Studies have shown that the frequency or worsening of sleep disorders tends to increase with age and that the ability to perform circadian adjustments tends to decrease in individuals who work the night shift. This condition can cause consequences such as excessive sleepiness, which are often a factor in accidents that occur at work. The present study investigated the effects of age on the daytime and nighttime sleep patterns using polysomnography (PSG of long-haul bus drivers working fixed night or day shifts. A total of 124 drivers, free of sleep disorders and grouped according to age (<45 years, N = 85, and ≥45 years, N = 39 and PSG timing (daytime (D PSG, N = 60; nighttime (N PSG, N = 64 participated in the study. We observed a significant effect of bedtime (D vs N and found that the length of daytime sleep was shorter [D: <45 years (336.10 ± 73.75 min vs N: <45 years (398 ± 78.79 min and D: ≥45 years (346.57 ± 43.17 min vs N: ≥45 years (386.44 ± 52.92 min; P ≤ 0.05]. Daytime sleep was less efficient compared to nighttime sleep [D: <45 years (78.86 ± 13.30% vs N: <45 years (86.45 ± 9.77% and D: ≥45 years (79.89 ± 9.45% and N: ≥45 years (83.13 ± 9.13%; P ≤ 0.05]. An effect of age was observed for rapid eye movement sleep [D: <45 years (18.05 ± 6.12% vs D: ≥45 years (15.48 ± 7.11% and N: <45 years (23.88 ± 6.75% vs N: ≥45 years (20.77 ± 5.64%; P ≤ 0.05], which was greater in younger drivers. These findings are inconsistent with the notion that older night workers are more adversely affected than younger night workers by the challenge of attempting to rest during the day.

  18. Field evaluation of traditionally used plant-based insect repellents and fumigants against the malaria vector Anopheles darlingi in Riberalta, Bolivian Amazon.

    Science.gov (United States)

    Moore, Sarah J; Hill, Nigel; Ruiz, Carmen; Cameron, Mary M

    2007-07-01

    Inexpensive insect repellents may be needed to supplement the use of impregnated bed-nets in the Amazon region, where the primary malaria vector, Anopheles darlingi (Root), is exophilic and feeds in the early evening. Three plants that are traditionally used to repel mosquitoes in Riberalta, Bolivian Amazon, were identified by focus group, and then they were tested against An. darlingi as well as Mansonia indubitans (Dyar & Shannon)/Mansonia titillans (Walker). Cymbopogon citratus (Staph), Guatemalan lemongrass, essential oil at 25% was used as a skin repellent, and it provided 74% protection for 2.5 h against predominantly An. darlingi and 95% protection for 2.5 h against Mansonia spp. Attalea princeps (name not verified) husks, burned on charcoal in the traditional way provided 35 and 51% protection against An. darlingi and Mansonia spp., respectively. Kerosene lamps, often used to light rural homes, were used as a heat source to volatilize 100% Mentha arvensis (Malinv ex. Bailey) essential oil, and they reduced biting by 41% inside traditional homes against Mansonia spp., although they were ineffective outdoors against An. darlingi. All three plant-based repellents provided significant protection compared with controls. Plant-based repellents, although less effective than synthetic alternatives, were shown by focus groups to be more culturally acceptable in this setting, in particular para-menthane-3, 8, idol derived from lemon eucalyptus, Corymbia citriodora (Hook). Plant-based repellents have the potential to be produced locally and therefore sold more cheaply than synthetic commercial repellents. Importantly, their low cost may encourage user compliance among indigenous and marginalized populations.

  19. Toxicity of a plant based mosquito repellent/killer.

    Science.gov (United States)

    Singh, Bhoopendra; Singh, Prakash Raj; Mohanty, Manoj Kumar

    2012-12-01

    The mission to make humans less attractive to mosquitoes has fuelled decades of scientific research on mosquito behaviour and control. The search for the perfect topical insect repellent/killer continues. This analysis was conducted to review and explore the scientific information on toxicity produced by the ingredients/contents of a herbal product. In this process of systemic review the following methodology was applied. By doing a MEDLINE search with key words of selected plants, plant based insect repellents/killers pertinent articles published in journals and authentic books were reviewed. The World Wide Web and the Extension Toxicity Network database (IPCS-ITOX) were also searched for toxicology data and other pertinent information. Repellents do not all share a single mode of action and surprisingly little is known about how repellents act on their target insects. Moreover, different mosquito species may react differently to the same repellent. After analysis of available data and information on the ingredient, of the product in relation to medicinal uses, acute and chronic toxicity of the selected medicinal plants, it can be concluded that the ingredients included in the herbal product can be used as active agents against mosquitoes. If the product which contains the powder of the above said plants is applied with care and safety, it is suitable fo use as a mosquito repellent/killer.

  20. Using Ethanol to Investigate Dynamic Soil Water Repellency

    Science.gov (United States)

    Smith, James E.; Beatty, Sarah M.

    2016-04-01

    Large gaps remain in our fundamental understanding of the behaviour of water in dynamically repellent soils. By investigating these systems using other miscible fluids that minimize or eliminate repellency, e.g. ethanol, we seek to better understand and quantify soil water repellency. The advantages of the enhanced wettability of water repellent soils to other miscible fluids, however, come with complications including shifts in effective pore water pressures induced through variable interfacial tensions as well as differences in fluid mobility due to variable fluid viscosities and densities. With these considerations in mind, we compare and contrast the observed behaviours of fluid infiltration and retention in dynamically hydrophobic soils and hydrophilic soils. We conducted field and laboratory studies using tension disc infiltrometers along with water and ethanol solutions to investigate dynamic repellency in post-wildfire soils from Northern Ontario, Canada. Tension infiltrometers maintain a constant negative liquid pressure at the surface which proved to be useful for isolating wettable behaviours sensitive to dynamic changes in wettability. We present the data and system conceptualised and explained through contact angle dynamics and variable fractional wettability of the soil. The limitations of extending hydrophilic concepts and hydraulic functions to hydrophobic soils are discussed along with persistent challenges to advance our ability to simulate and predict system behaviours in naturally occurring water repellent soils.

  1. Do topical repellents divert mosquitoes within a community? Health equity implications of topical repellents as a mosquito bite prevention tool.

    Science.gov (United States)

    Maia, Marta Ferreira; Onyango, Sangoro Peter; Thele, Max; Simfukwe, Emmanuel Titus; Turner, Elizabeth Louise; Moore, Sarah Jane

    2013-01-01

    Repellents do not kill mosquitoes--they simply reduce human-vector contact. Thus it is possible that individuals who do not use repellents but dwell close to repellent users experience more bites than otherwise. The objective of this study was to measure if diversion occurs from households that use repellents to those that do not use repellents. The study was performed in three Tanzanian villages using 15%-DEET and placebo lotions. All households were given LLINs. Three coverage scenarios were investigated: complete coverage (all households were given 15%-DEET), incomplete coverage (80% of households were given 15%-DEET and 20% placebo) and no coverage (all households were given placebo). A crossover study design was used and coverage scenarios were rotated weekly over a period of ten weeks. The placebo lotion was randomly allocated to households in the incomplete coverage scenario. The level of compliance was reported to be close to 100%. Mosquito densities were measured through aspiration of resting mosquitoes. Data were analysed using negative binomial regression models. Repellent-users had consistently fewer mosquitoes in their dwellings. In villages where everybody had been given 15%-DEET, resting mosquito densities were fewer than half that of households in the no coverage scenario (Incidence Rate Ratio [IRR]=0.39 (95% confidence interval [CI]: 0.25-0.60); pmosquitoes (IRR=4.17; 95% CI: 3.08-5.65; pmosquitoes are diverted from households that use repellent to those that do not. Therefore, if repellents are to be considered for vector control, strategies to maximise coverage are required.

  2. [Visual efficiency of pilot using of the night vision glasses].

    Science.gov (United States)

    Davydov, V V; Ivanov, A I; Lapa, V V; Romasiuk, S I; Riabinin, V A; Chuntul, A V; Prokof'ev, A B

    2007-01-01

    Questionnaires filled out by 24 helicopter pilots using the night vision glasses (NVG) showed that minimization of the risk of visual discomfort was, first of all achieved through proper adjustment of image brightness and setting NVG time limits. The experiments enabled determination of the most favorable range of brightness (0.67-1.79 cd/m2) and rationalization of the necessity of individual adjustment depending on the light conditions and flight objectives, and NVG usage regulations to preclude visual fatigue.

  3. Repellent activities of dichloromethane extract of Allium sativum (garlic (Liliaceae against Hyalomma rufipes (Acari

    Directory of Open Access Journals (Sweden)

    Felix Nchu

    2016-02-01

    Full Text Available Dichloromethane (DCM extract of garlic (Allium sativum Linn. bulbs was assessed for its repellent effect against the hard tick, Hyalomma rufipes (Acari: Ixodidae using two tick behavioural bioassays; Type A and Type B repellency bioassays, under laboratory conditions. These bioassays exploit the questing behaviour of H. rufipes, a tick that in nature displays ambush strategy, seeking its host by climbing up on vegetation and attaching to a passing host. One hundred microlitres (100 µL of the test solution containing DCM extract of garlic bulbs and DCM at concentrations of 0.35%, 0.7% or 1.4% w/v were evaluated. DCM only was used for control. Tick repellency increased significantly (R2 = 0.98 with increasing concentration (40.03% – 86.96% yielding an EC50 of 0.45% w/v in Type B repellency bioassay. At concentration of 1.4% w/v, the DCM extract of garlic bulbs produced high repellency index of 87% (male ticks and 87.5% (female ticks in the Type A repellency bioassay. Only 4% avoidance of male ticks or female ticks was recorded in the Type B repellency bioassay. In the corresponding controls, the mean numbers of non-repelled male or female ticks were 80% and 41 males or 38 females of 50 ticks in the Type A and Type B repellency bioassays, respectively. The variations in the results could be attributed to the difference in tick repellent behaviours that were assessed by the two repellency bioassays; the Type A repellency bioassay assessed repellent effect of garlic extracts without discriminating between deterrence and avoidance whereas the Type B repellency bioassay only assessed avoidance response. Generally, DCM extract of garlic was repellent against H. rufipes, albeit weak tick repellency was obtained in the Type B repellency bioassay. Furthermore, this study established that the tick repellent activity of garlic extracts is predominantly by deterrence.

  4. Repellent activities of dichloromethane extract of Allium sativum (garlic) (Liliaceae) against Hyalomma rufipes (Acari).

    Science.gov (United States)

    Nchu, Felix; Magano, Solomon R; Eloff, Jacobus N

    2016-12-02

    Dichloromethane (DCM) extract of garlic (Allium sativum Linn.) bulbs was assessed for its repellent effect against the hard tick, Hyalomma rufipes (Acari: Ixodidae) using two tick behavioural bioassays; Type A and Type B repellency bioassays, under laboratory conditions. These bioassays exploit the questing behaviour of H. rufipes, a tick that in nature displays ambush strategy, seeking its host by climbing up on vegetation and attaching to a passing host. One hundred microlitres (100 µL) of the test solution containing DCM extract of garlic bulbs and DCM at concentrations of 0.35%, 0.7% or 1.4% w/v were evaluated. DCM only was used for control. Tick repellency increased significantly (R2 = 0.98) with increasing concentration (40.03% - 86.96%) yielding an EC50 of 0.45% w/v in Type B repellency bioassay. At concentration of 1.4% w/v, the DCM extract of garlic bulbs produced high repellency index of 87% (male ticks) and 87.5% (female ticks) in the Type A repellency bioassay. Only 4% avoidance of male ticks or female ticks was recorded in the Type B repellency bioassay. In the corresponding controls, the mean numbers of non-repelled male or female ticks were 80% and 41 males or 38 females of 50 ticks in the Type A and Type B repellency bioassays, respectively. The variations in the results could be attributed to the difference in tick repellent behaviours that were assessed by the two repellency bioassays; the Type A repellency bioassay assessed repellent effect of garlic extracts without discriminating between deterrence and avoidance whereas the Type B repellency bioassay only assessed avoidance response. Generally, DCM extract of garlic was repellent against H. rufipes, albeit weak tick repellency was obtained in the Type B repellency bioassay. Furthermore, this study established that the tick repellent activity of garlic extracts is predominantly by deterrence.

  5. Housing under abnormal light-dark cycles attenuates day/night expression rhythms of the clock genes Per1, Per2, and Bmal1 in the amygdala and hippocampus of mice.

    Science.gov (United States)

    Moriya, Shunpei; Tahara, Yu; Sasaki, Hiroyuki; Ishigooka, Jun; Shibata, Shigenobu

    2015-10-01

    Although the results of previous studies have suggested that disruptions in circadian rhythms are involved in the pathogenesis of depression, no studies have examined the interaction of clock gene expression deficit and depression state. In this study, we examined clock gene expression levels and depressive-like behavior in mice housed under 3.5h light, 3.5h dark (T = 7) conditions to investigate the association between clock gene expression and depressive state. C57BL/6J mice were housed under a T = 24 cycle (12h light, 12h dark) or a T = 7 cycle and clock gene expression levels in the hippocampus and the amygdala were measured by real-time RT-PCR. Depressive state was evaluated by the forced swim test (FST). Although circadian rhythms of Per1 and Per2 clock gene expression in the hippocampus and amygdala were still detected under T = 7 conditions, rhythmicity and expression levels of both significantly decreased. Mice housed with a T = 7 cycle showed increased immobile time in the FST than those with a T = 24 cycle. The present results suggest that the presence of a depressive state around the early active phase of activity may be related to impairment of rhythmicity and expression levels of Per1 and Per2 genes under abnormal light-dark conditions.

  6. Night shift work and modifiable lifestyle factors

    Directory of Open Access Journals (Sweden)

    Beata Pepłońska

    2014-10-01

    Full Text Available Objectives: Night shift work has been linked to some chronic diseases. Modification of lifestyle by night work may partially contribute to the development of these diseases, nevertheless, so far epidemiological evidence is limited. The aim of the study was to explore association between night shift work and lifestyle factors using data from a cross-sectional study among blue-collar workers employed in industrial plants in Łódź, Poland. Material and Methods: The anonymous questionnaire was self-administered among 605 employees (236 women and 369 men, aged 35 or more - 434 individuals currently wor­king night shifts. Distribution of the selected lifestyle related factors such as smoking, alcohol drinking, physical activity, body mass index (BMI, number of main meals and the hour of the last meal was compared between current, former, and never night shift workers. Adjusted ORs or predicted means were calculated, as a measure of the associations between night shift work and lifestyle factors, with age, marital status and education included in the models as covariates. Results: Recreational inactivity (defined here as less than one hour per week of recreational physical activity was associated with current night shift work when compared to never night shift workers (OR = 2.43, 95% CI: 1.13-5.22 among men. Alcohol abstinence and later time of the last meal was associated with night shift work among women. Statistically significant positive relationship between night shift work duration and BMI was observed among men (p = 0.029. Conclusions: This study confirms previous studies reporting lower exercising among night shift workers and tendency to increase body weight. This finding provides important public health implication for the prevention of chronic diseases among night shift workers. Initiatives promoting physical activity addressed in particular to the night shift workers are recommended.

  7. The new world atlas of artificial night sky brightness

    CERN Document Server

    Falchi, Fabio; Duriscoe, Dan; Kyba, Christopher C M; Elvidge, Christopher D; Baugh, Kimberly; Portnov, Boris A; Rybnikova, Nataliya A; Furgoni, Riccardo

    2016-01-01

    Artificial lights raise night sky luminance, creating the most visible effect of light pollution-artificial skyglow. Despite the increasing interest among scientists in fields such as ecology, astronomy, health care, and land-use planning, light pollution lacks a current quantification of its magnitude on a global scale. To overcome this, we present the world atlas of artificial sky luminance, computed with our light pollution propagation software using new high-resolution satellite data and new precision sky brightness measurements. This atlas shows that more than 80% of the world and more than 99% of the U.S. and European populations live under light-polluted skies. The Milky Way is hidden from more than one-third of humanity, including 60% of Europeans and nearly 80% of North Americans. Moreover, 23% of the world's land surfaces between 75{\\deg}N and 60{\\deg}S, 88% of Europe, and almost half of the United States experience light-polluted nights.

  8. The new world atlas of artificial night sky brightness.

    Science.gov (United States)

    Falchi, Fabio; Cinzano, Pierantonio; Duriscoe, Dan; Kyba, Christopher C M; Elvidge, Christopher D; Baugh, Kimberly; Portnov, Boris A; Rybnikova, Nataliya A; Furgoni, Riccardo

    2016-06-01

    Artificial lights raise night sky luminance, creating the most visible effect of light pollution-artificial skyglow. Despite the increasing interest among scientists in fields such as ecology, astronomy, health care, and land-use planning, light pollution lacks a current quantification of its magnitude on a global scale. To overcome this, we present the world atlas of artificial sky luminance, computed with our light pollution propagation software using new high-resolution satellite data and new precision sky brightness measurements. This atlas shows that more than 80% of the world and more than 99% of the U.S. and European populations live under light-polluted skies. The Milky Way is hidden from more than one-third of humanity, including 60% of Europeans and nearly 80% of North Americans. Moreover, 23% of the world's land surfaces between 75°N and 60°S, 88% of Europe, and almost half of the United States experience light-polluted nights.

  9. Do topical repellents divert mosquitoes within a community? Health equity implications of topical repellents as a mosquito bite prevention tool.

    Directory of Open Access Journals (Sweden)

    Marta Ferreira Maia

    Full Text Available OBJECTIVES: Repellents do not kill mosquitoes--they simply reduce human-vector contact. Thus it is possible that individuals who do not use repellents but dwell close to repellent users experience more bites than otherwise. The objective of this study was to measure if diversion occurs from households that use repellents to those that do not use repellents. METHODS: The study was performed in three Tanzanian villages using 15%-DEET and placebo lotions. All households were given LLINs. Three coverage scenarios were investigated: complete coverage (all households were given 15%-DEET, incomplete coverage (80% of households were given 15%-DEET and 20% placebo and no coverage (all households were given placebo. A crossover study design was used and coverage scenarios were rotated weekly over a period of ten weeks. The placebo lotion was randomly allocated to households in the incomplete coverage scenario. The level of compliance was reported to be close to 100%. Mosquito densities were measured through aspiration of resting mosquitoes. Data were analysed using negative binomial regression models. FINDINGS: Repellent-users had consistently fewer mosquitoes in their dwellings. In villages where everybody had been given 15%-DEET, resting mosquito densities were fewer than half that of households in the no coverage scenario (Incidence Rate Ratio [IRR]=0.39 (95% confidence interval [CI]: 0.25-0.60; p<0.001. Placebo-users living in a village where 80% of the households used 15%-DEET were likely to have over four-times more mosquitoes (IRR=4.17; 95% CI: 3.08-5.65; p<0.001 resting in their dwellings in comparison to households in a village where nobody uses repellent. CONCLUSIONS: There is evidence that high coverage of repellent use could significantly reduce man-vector contact but with incomplete coverage evidence suggests that mosquitoes are diverted from households that use repellent to those that do not. Therefore, if repellents are to be considered for

  10. An investigation of stereopsis with AN/AVS-6 night vision goggles at varying levels of illuminance and contrast

    OpenAIRE

    Armentrout, Jeffrey J.

    1993-01-01

    The increased reliance on night operations by the military over the last few decades has led to the development of various night imaging devices. Night vision goggles (NVGs) are one device which have gained widespread use in nighttime helicopter operations. However, rotorcraft accident data have indicated an increased occurrence of "pilot error" type accidents when NVGs are in use. NVG related accidents often can be linked to extremely poor ambient lighting and contras...

  11. Night vision: changing the way we drive

    Science.gov (United States)

    Klapper, Stuart H.; Kyle, Robert J. S.; Nicklin, Robert L.; Kormos, Alexander L.

    2001-03-01

    A revolutionary new Night Vision System has been designed to help drivers see well beyond their headlights. From luxury automobiles to heavy trucks, Night Vision is helping drivers see better, see further, and react sooner. This paper describes how Night Vision Systems are being used in transportation and their viability for the future. It describes recent improvements to the system currently in the second year of production. It also addresses consumer education and awareness, cost reduction, product reliability, market expansion and future improvements.

  12. Night ventilation control strategies in office buildings

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhaojun; Yi, Lingli; Gao, Fusheng [School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090 (China)

    2009-10-15

    In moderate climates night ventilation is an effective and energy-efficient approach to improve the indoor thermal environment for office buildings during the summer months, especially for heavyweight construction. However, is night ventilation a suitable strategy for office buildings with lightweight construction located in cold climates? In order to answer this question, the whole energy-consumption analysis software EnergyPlus was used to simulate the indoor thermal environment and energy consumption in typical office buildings with night mechanical ventilation in three cities in northern China. The summer outdoor climate data was analyzed, and three typical design days were chosen. The most important factors influencing night ventilation performance such as ventilation rates, ventilation duration, building mass and climatic conditions were evaluated. When night ventilation operation time is closer to active cooling time, the efficiency of night ventilation is higher. With night ventilation rate of 10 ach, the mean radiant temperature of the indoor surface decreased by up to 3.9 C. The longer the duration of operation, the more efficient the night ventilation strategy becomes. The control strategies for three locations are given in the paper. Based on the optimized strategies, the operation consumption and fees are calculated. The results show that more energy is saved in office buildings cooled by a night ventilation system in northern China than ones that do not employ this strategy. (author)

  13. New Candidates for Plant-Based Repellents Against Aedes aegypti.

    Science.gov (United States)

    Misni, Norashiqin; Nor, Zurainee Mohamed; Ahmad, Rohani

    2016-06-01

    Based on an ethnobotanical study on use for plant species against mosquito bites in the Kota Tinggi District, Johor State, Malaysia, 3 plants selected for study, Citrus aurantifolia (leaves), Citrus grandis (fruit peel), and Alpinia galanga (rhizome), were extracted using hydrodistillation to produce essential oils. These essential oils were then formulated as a lotion using a microencapsulation process and then tested for their repellent effect against Aedes aegypti. N,N-diethyl-m-toluamide (deet) was also prepared in the same formulation and tested for repellency as controls. Four commercial plant-based repellent (KAPS(®), MozAway(®), BioZ Natural(®), and Mosiquard(®)) also were incorporated in the bioassay for comparison purposes. Bioassays revealed that at 20% concentration all repellent formulations demonstrated complete protection for 2 h and >90% for 4 h post-application. The A. galanga-based formulation provided the greatest level of protection (98.91%), which extended for 4 h post-application and was not significantly different from deet at similar concentration. When compared with commercial plant-based repellents (KAPS(®), MozAway(®), and BioZ Natural(®)), the 3 lotion formulations showed significantly better protection against Ae. aegypti bites, providing >90% protection for 4 h. In conclusion, our 3 plant-based lotion formulations provided acceptable levels of protection against host-seeking Ae. aegypti and should be developed.

  14. Mosquito repellent activity of volatile oils from selected aromatic plants.

    Science.gov (United States)

    Lalthazuali; Mathew, Nisha

    2017-02-01

    Essential oils from fresh leaves of four aromatic plants viz., Ocimum sanctum, Mentha piperita, Eucalyptus globulus and Plectranthus amboinicus were extracted by hydrodistillation. The test solutions were prepared as 20% essential oil in ethanol and positive control as 20% DEET in ethanol. Essential oil blend was prepared as 5% concentration. Nulliparous, 3-5-day-old female adult Aedes aegypti mosquitoes were used for repellency screening as per ICMR protocol. The study showed that the repellency of 20% essential oil of O. sanctum, M. piperita and P. amboinicus were comparable with that of the standard DEET (20%) as no mosquito landing on the test was observed up to 6 h. The E. globulus oil exhibited mosquito repellency only upto 1½ h. Considerable mosquito landing and feeding was displayed in negative control. In the case of the oil blend, no landing of mosquitoes was seen up to 6 h as that of positive control. The results showed that the essential oil blend from O. sanctum, M. piperita, E. globulus and P. amboinicus could repel Ae. aegypti mosquitoes or prevent from feeding as in the case of DEET even at a lower concentration of 5%. This study demonstrates the potential of essential oils from O. sanctum, M. piperita, E. globulus and P. amboinicus and their blend as mosquito repellents against Ae. aegypti, the vector of dengue, chikungunya and yellow fever.

  15. Approaches to characterize the degree of water repellency

    Science.gov (United States)

    Letey, J.; Carrillo, M. L. K.; Pang, X. P.

    2000-05-01

    Measurement techniques that quantify the degree of soil water repellency are important for research and for the communication of research findings. The water drop penetration time (WDPT) is a commonly used measurement. If a water drop does not enter the soil spontaneously, the soil-water contact angle is greater than 90° and the soil is considered to be water repellent. The time for the drop to enter the soil (WDPT) provides an indication of the stability of the repellency. The liquid-air surface tension of an aqueous ethanol concentration series that enters the soil in approximately 5 s is identified as the ninety degree (ND) surface tension, γND, of the soil. The γND number can be used to calculate the solid-air surface tension, γs, by γs= γND/4. The water-soil contact angle can also be calculated from the γs value by the relationship cos θ=[(γ ND/γ w) 1/2-1], where θ is the contact angle and γw the water-air surface tension. The water entry pressure, hp, which is a function of both the soil water repellency and pore size, is an important parameter for predicting infiltration and the stability of water flow in the field. Measurements of WDPT, γND, and hp provide a complete characterization of the degree of water repellency.

  16. Repellent effect of Lagenaria siceraria extracts against Culex pipiens.

    Science.gov (United States)

    Hassan, Mostafa I; Fouda, Mohamad A; Hammad, Kotb M; Tanani, Mohamad A; Shehata, Ahmed Z

    2014-04-01

    Ethanolic, acetone and petroleum ether extracts from leaves and stems of Lagenaria siceraria (Cucurbitaceae) were screened for their repellency effect against Culex pipiens L. mosquito. The repellent action of the present plant extracts were varied depending on the plant parts and the dose of extract. The petroleum ether extract of leaves showed the same repellency percent (100%) of commercial formulation, N. N.diethyl toulamide (DEET) at the higher dose (3.33 mg/cm2), while petroleum ether extract from stems exhibiting the repellent action (89.6%) at the same dose, respectively. Ethanolic extracts of leaves and stems exhibited the lowest repellent activity as it recorded (81.3% and 69.1%) at (6.67 mg/cm2), respectively. Results of this study may contribute to design an alternative way to control mosquitoes currently based on applications of synthetic insecticides. These extracts could be developed commercially as an effective personal protection measure against mosquito bites and thus to control diseases caused by mosquito-borne pathogens.

  17. Insect repellents and associated personal protection for a reduction in human disease

    Science.gov (United States)

    Personal protection measures against biting arthropods include topical insect repellents, area repellents, insecticide-treated bednets and treated clothing. The literature on the effectiveness of personal protection products against arthropods is mainly limited to studies of prevention of bites, rat...

  18. Plant-based insect repellents: a review of their efficacy, development and testing

    Directory of Open Access Journals (Sweden)

    Maia Marta

    2011-03-01

    Full Text Available Abstract Plant-based repellents have been used for generations in traditional practice as a personal protection measure against host-seeking mosquitoes. Knowledge on traditional repellent plants obtained through ethnobotanical studies is a valuable resource for the development of new natural products. Recently, commercial repellent products containing plant-based ingredients have gained increasing popularity among consumers, as these are commonly perceived as “safe” in comparison to long-established synthetic repellents although this is sometimes a misconception. To date insufficient studies have followed standard WHO Pesticide Evaluation Scheme guidelines for repellent testing. There is a need for further standardized studies in order to better evaluate repellent compounds and develop new products that offer high repellency as well as good consumer safety. This paper presents a summary of recent information on testing, efficacy and safety of plant-based repellents as well as promising new developments in the field.

  19. How do different definitions of night shift affect the exposure assessment of night work?

    DEFF Research Database (Denmark)

    Garde, Anne Helene; Hansen, Johnni; Kolstad, Henrik A

    2016-01-01

    The aim is to show how different definitions affect the proportion of shifts classified as night shifts. The Danish Working Hour Database was used to calculate number of night shifts according to eight definitions. More than 98% of the total night shifts were night shifts by use of both...... the reference definition (at least 3 h of work between 24:00 and 05:00) and definitions using a period during the night. The overlap with definitions based on starting and ending time was less pronounced (64-71 %). The proportion of classified night shifts differs little when night shifts are based...... on definitions including a period during the night. Studies based on other definitions may be less comparable....

  20. Metabolic syndrome in permanent night workers.

    Science.gov (United States)

    Biggi, Nicoletta; Consonni, Dario; Galluzzo, Valeria; Sogliani, Marco; Costa, Giovanni

    2008-04-01

    Night and shift work might be risk factors for metabolic and cardiovascular disorders due to interference with diet, circadian metabolic rhythms, and lifestyle. The relationship between permanent night work and metabolic and cardiovascular risk factors was explored in a retrospective longitudinal study of workers employed in a large municipal enterprise in charge of street cleaning and domestic waste collection. All subjects who had worked night shifts between 1976 and 2007 as hand sweepers, motor sweepers, and delivery tricar drivers were compared with subjects who always worked the same jobs but on day shifts. From the periodical medical surveillance files, we identified 488 male workers who had been examined on average five times (minimum 2, maximum 14) during the study period, for a total of 2,328 medical examinations; 157 always had worked day shifts, 12 always the night shift, and 319 both (initially day and subsequently night shifts). Their age ranged from 22 to 62 yrs, and work experience varied from 1 to 28 yrs. Lifestyle habits (smoking, alcohol consumption), body mass index, serum glucose, total cholesterol, tryglicerides, hepatic enzymes, blood pressure, resting electrocardiogram, diabetes, coronary heart disease, hypertension, and related drugs were taken into consideration for the analysis. We used generalized estimating equations (GEE) models (exchangeable correlation matrix) to analyze the relationship between night work and health effects while accounting for within-subject correlations and adjusting for study period, job, age, and lifestyle variables. As a whole, night workers smoked more and had significantly higher BMI, serum total cholesterol, and triglycerides than day workers. Both the inter-individual comparison between day and night workers and the intra-individual comparison among the workers, who were day workers at the beginning of their employment and later became night workers, showed a significant increase in BMI, total cholesterol

  1. The night sky brightness at Potsdam-Babelsberg including overcast and moonlit conditions

    Science.gov (United States)

    Puschnig, Johannes; Schwope, Axel; Posch, Thomas; Schwarz, Robert

    2014-05-01

    We analyze the results of 2 years (2011-2012) of night sky photometry performed at the Leibniz Institute for Astrophysics in Potsdam-Babelsberg. This institute is located 23 km to the southwest of the center of Berlin. Our measurements have been performed with a Sky Quality Meter. We find night sky brightness values ranging from 16.5 to 20.3 magSQM arcsec-2; the latter value corresponds to 4.8 times the natural zenithal night sky brightness. We focus on the influence of clouds and of the moon on the night sky brightness. It turns out that Potsdam-Babelsberg, despite its proximity to Berlin, still shows a significant correlation of the night sky brightness with the lunar phases. However, the light-pollution-enhancing effect of clouds dominates the night sky brightness by far: overcast nights (up to 16.5 magSQM arcsec-2) are much brighter than clear full moon nights (18-18.5 magSQM arcsec-2).

  2. Effect of Cultural Practices in Night on Weed Density and Weed Dry Matter

    Directory of Open Access Journals (Sweden)

    M.H Rashed Mohasel

    2011-01-01

    Full Text Available Abstract In order to evaluate the response of weed seeds to light, two experiments, at two different locations were conducted at Ferdowsi university of Mashhad in 2009. At the first experiment, field was ploughed in day and night. Weed density was evaluated 70 d after plough, with 1×1 quadrate. At the second experiment, at night treatment, ploughing, potato planting and weeding with cultivator were done at night. Weed sampling was done twice at 43 and 130 days after planting with 1×1 quadrate and weeds were identified and counted. Result showed pigweed (Amaranthus retroflexus L., sowthistle (Sonchus oleraceus L., crabgrass (Digitaria sanguinalis (L. scop, jimsonweed (Datura stramonium L. and mallow (Hibiscus trionum L. did not observed at night plough, in contrast, night plough has no significance influence on common lambsquarters (Chenopodium album L., and black nightshade (Solanum nigrum L.. Only common lambsquarters had similar appearance in two treatments, indicating insusceptibility of this weed to time of plough. Interestingly, at the second experiment, result was very similar. Potato yield was higher at night treatment, but not significant. This research showed that some cultural practice like plough, planting and weeding with cultivator in night can reduce weed density and weed dry matter. Keywords: Germination, Time of plough, Sustainable weeds management, Light

  3. Handling qualities comparison of panoramic night vision goggles and 46-deg. night vision goggles

    Science.gov (United States)

    Craig, Gregory; Jennings, Sion; Thorndycraft, David

    2003-09-01

    Night Vision Goggles allow the user to see in extremely low illumination levels but the visual information provided by Night Vision Goggles has a limited field-of-view that diminishes handling-qualities in the night flying environment. Panoramic Night Vision Goggles were designed to correct this problem by providing a 100° horizontal field-of-view which is larger than currently used Night Vision Goggles. However, in the first generation Panoramic Night Vision Goggle, the improved field of view came at the cost of diminished resolution, contrast and central overlap area when compared to conventional Night Vision Goggles. This paper describes an evaluation that was conducted in the variable stability NRC Bell-205 helicopter to examine the influence on system handling qualities of the Panoramic Night Vision Goggles and a 46° field-of-view UK Night Vision Goggle. Five pilots flew the ADS-33D hover, sidestep and pirouette manoeuvres in simulated night conditions with the UK Night Vision Goggle and the Panoramic Night Vision Goggle. Both subjective and objective measures of task performance were obtained. Handling-qualities ratings showed the pirouette was performed better with the Panoramic Night Vision Goggles. This was the only manoeuvre where there was a clear-cut handling qualities improvement when using the Panoramic Night Vision Goggles. Other manoeuvres such as the sidestep and hover did not show definitive handling qualities rating differences between the two Night Vision Goggle types. The flight test results were interpreted in terms of the design trade-offs of the two night vision systems, with regard to the different acuity, binocular overlaps and fields-of-view.

  4. Fifty years ago: the Vaiont night

    Directory of Open Access Journals (Sweden)

    Valerio Spagna

    2012-07-01

    Full Text Available A geologist at the beginning of his career in the early 1960’s was a teacher of mineralogy and geology at the Agordo “Follador” Mining Institute in the Dolomites area. It was 50 years ago now when he observed the building of the Vaiont dam, and here he tells us of the night of October 9, 1963, when he rushed to the Piave Valley together with the first-aid teams, to confront the remains of Longarone. Did the dam collapse? Everybody thinks so, but the moon was not shining enough to allow an understanding of what had happened. It was only the first faint light of dawn that revealed that the dam was still standing: it was only edged by the water, from the shaping of the tremendous wave that was raised by the Mount Toc landslide when it entered the basin at 100 km/h. The dam edge contributed to the projection of the wave onto the opposite slopes, where once the water mass was released from the narrow Vaiont canyon, it raised solidly into the air, grazing the Casso village and precipitated as a massive block on the Longarone area. Everybody looked upwards with hate and despair, at the residual water streamlets that were overflowing along the concrete wall of the dam. Over the white bare esplanade people appeared extremely small. Pitiful people, gathered around the bodies wrenched from the devastated houses, denuded and buried in the mud.

  5. Night-vision goggles for night-blind subjects : subjective evaluation after 2 years of use

    NARCIS (Netherlands)

    Hartong, D. T.; Kooijman, A. C.

    2006-01-01

    Purpose: To evaluate the usefulness of night-vision goggles (NVG) for night-blind subjects after 1 and 2 years of use. Methods: Eleven night-blind subjects with retinitis pigmentosa used NVG for a 2-year period. At the end of each year, they were requested to fill-in two questionnaires regarding the

  6. Coating for Nano Super Soil-repellency of Cashmere Fabric

    Institute of Scientific and Technical Information of China (English)

    WANG Jin-mei; ZHU Chang-chun

    2005-01-01

    The nano-size metal oxide was prepared by the single-disperse technique on liquid phase, and formed sol clusters, its uniform film was covered on the surface of cashmere fibers by coating, and it had good oil repellency and water repellency. The results of IR(infrared) Spectrometer analysis revealed: The nano material combines through the strong bonds with the surface of cashmere fibers by the live groups.These analyses by SEM techniques showed that the nano material was distributed on the fiber surface even, and the nano material formed the strong peak of the regular crystal phase structure using the X-Ray Diffractometry (XRD) to analysis the fabric. The optimum techniques were selected by a series of experiments, coated cashmere fabric not only has preserved original properties of softness and comfort,but also has good properties of Bi-repellency function.Therefore, the technique will have potential application in engineers.

  7. The Citizen-Scientist as Data Collector: GLOBE at Night, Part 2

    Science.gov (United States)

    Walker, C. E.; Pompea, S. M.; Ward, D.; Henderson, S.; Meymaris, K.; Gallagher, S.; Salisbury, D.

    2006-12-01

    An innovative program to realize light pollution education on two continents via Internet 2-based videoconferencing was begun 4 years ago by the National Optical Astronomy Observatory. Bilingual science teachers and their students in Arizona and Chile recorded the brightness of the night sky by matching its appearance toward the constellation Orion with one of 6 stellar maps of limiting magnitude. Students from both hemispheres would report their findings via videoconferences. In the last year the program has evolved in collaboration with UCAR and other partners into an international, user-friendly, web-based science event open to anyone in the world, known as GLOBE at Night. GLOBE at Night uses the same design to observe and record the visible stars toward Orion, as a means of measuring light pollution in a given location. The inaugural event occurred over 11 nights last March, when 18,000 citizen- scientists made over 4,500 observations from 96 countries. Analysis of the GLOBE at Night data set found that the brighter skies corresponded to areas with higher population density, and that most observations were taken in a location with some light pollution. The data also tended to confirm that satellite data is reliable in assessing light pollution. This session will describe our program to incorporate more technology into the GLOBE at Night program. Citizen-scientists will use sky quality meters (visible light photometers), calibrated digital photography, and GPS as a means to measure and map more accurately the brightness of the sky at selected urban and rural sites. This extension of the program is designed to aid further in teaching about the impact of artificial lighting on local environments and the ongoing loss of a dark night sky as a natural resource. We will also describe how detailed maps of selected urban areas can be used to assess lighting design, safety considerations and energy usage. Given the widespread interest in the inaugural GLOBE at Night

  8. Why Does Asthma Attack Severely at Night?

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The rhythmic changes of human physiological activities by day and at night may cause regular change of the patient's condition within one day. The following is the explanation with the theory of Chinese medicine for the reason why asthma attacks severely at night.

  9. Definitions of night eating in adolescent girls

    NARCIS (Netherlands)

    Striegel-Moore, RH; Thompson, D; Franko, DL; Barton, B; Affenito, S; Schreiber, GB; Daniels, [No Value

    2004-01-01

    Objective: To describe the prevalence of night eating in a community cohort of black and white girls, using different definitions of night eating as described in the literature. Research Methods and Procedures: Three-day food diaries collected as part of the National Growth and Health Study were exa

  10. Field testing driver night vision devices

    NARCIS (Netherlands)

    Kooi, F.L.; Kolletzki, D.

    2007-01-01

    This paper summarizes the available methodologies to field test driver night vision devices ranging from vehicle mounted camera’s to head-mounted NVG’s. As in flight trials, a formidable challenge is to collect meaningful performance measures. Night vision systems for land and air systems show many

  11. Definitions of night eating in adolescent girls

    NARCIS (Netherlands)

    Striegel-Moore, RH; Thompson, D; Franko, DL; Barton, B; Affenito, S; Schreiber, GB; Daniels, [No Value

    Objective: To describe the prevalence of night eating in a community cohort of black and white girls, using different definitions of night eating as described in the literature. Research Methods and Procedures: Three-day food diaries collected as part of the National Growth and Health Study were

  12. Night time blood pressure dip

    Institute of Scientific and Technical Information of China (English)

    Dennis; Bloomfield; Alex; Park

    2015-01-01

    The advent of ambulatory blood pressure monitoring permitted examination of blood pressures during sleep and recognition of the associated circadian fall in pressure during this period. The fall in pressure,called the "dip",is defined as the difference between daytime mean systolic pressure and nighttime mean systolic pressure expressed as a percentage of the day value. Ten percent to 20% is considered normal. Dips less than 10%,referred to as blunted or absent,have been considered as predicting an adverse cardiovascular event. This view and the broader concept that white coat hypertension itself is a forerunner of essential hypertension is disputable. This editorial questions whether mean arterial pressures over many hours accurately represent the systolic load,whether nighttime dipping varies from measure to measure or is a fixed phenomenon,whether the abrupt morning pressure rise is a risk factor or whether none of these issues are as important as the actual night time systolic blood pressure itself. The paper discusses the difference between medicated and nonmedicated white coat hypertensives in regard to the cardiovascular risk and suggests that further work is necessary to consider whether the quality and duration of sleep are important factors.

  13. Development of novel repellents using structure-activity modeling of compounds in the USDA archival database

    Science.gov (United States)

    The United States Department of Agriculture (USDA) has developed repellents and insecticides for the U.S. military since 1942. Repellency and toxicity data for over 30,000 compounds are contained within the USDA archive. Repellency data from subsets of similarly structured compounds were used to dev...

  14. Fire-induced water repellency: An erosional factor in wildland environments

    Science.gov (United States)

    Leonard F. DeBano

    2000-01-01

    Watershed managers and scientists throughout the world have been aware of fire-induced water-repellent soils for over three decades. Water repellency affects many hydrologic processes, including infiltration, overland flow, and surface erosion (rill and sheet erosion). This paper describes; the formation of fire-induced water-repellent soils, the effect of soil water...

  15. Antennal olfactory sensilla responses to insect chemical repellents in the common bed bug, Cimex lectularius.

    Science.gov (United States)

    Liu, Feng; Haynes, Kenneth F; Appel, Arthur G; Liu, Nannan

    2014-06-01

    Populations of the common bed bug Cimex lectularius (Hemiptera; Cimicidae), a temporary ectoparasite on both humans and animals, have surged in many developed countries. Similar to other haematophagous arthropods, C. lectularius relies on its olfactory system to detect semiochemicals in the environment, including both attractants and repellents. To elucidate the olfactory responses of the common bed bug to commonly used insect chemical repellents, particularly haematophagous repellents, we investigated the neuronal responses of individual olfactory sensilla in C. lectularius' antennae to 52 insect chemical repellents, both synthetic and botanic. Different types of sensilla displayed highly distinctive response profiles. While C sensilla did not respond to any of the insect chemical repellents, Dγ sensilla proved to be the most sensitive in response to terpene-derived insect chemical repellents. Different chemical repellents elicited neuronal responses with differing temporal characteristics, and the responses of the olfactory sensilla to the insect chemical repellents were dose-dependent, with an olfactory response to the terpene-derived chemical repellent, but not to the non-terpene-derived chemical repellents. Overall, this study furnishes a comprehensive map of the olfactory response of bed bugs to commonly used insect chemical repellents, providing useful information for those developing new agents (attractants or repellents) for bed bug control.

  16. Natural and fire-induced soil water repellency in a Portugese Shrubland

    NARCIS (Netherlands)

    Stoof, C.R.; Moore, D.; Ritsema, C.J.; Dekker, L.W.

    2011-01-01

    Post-fire land degradation is often attributed to fire-induced soil water repellency, despite the fact that soil water repellency is a natural phenomenon in many soils and is therefore not necessarily caused by fire. To improve our understanding of the role of soil water repellency in causing fire-i

  17. Development of Hydrophobic Coatings for Water-Repellent Surfaces Using Hybrid Methodology

    Science.gov (United States)

    2014-04-01

    windows, optical components, protective eyewear, and clothing, this type of surface is desired for the material to be soil repellent and water ...Development of Hydrophobic Coatings for Water - Repellent Surfaces Using Hybrid Methodology by Amanda S. Weerasooriya, Jacqueline Yim, Andres A...Proving Ground, MD 21005-5069 ARL-TR-6898 April 2014 Development of Hydrophobic Coatings for Water - Repellent Surfaces Using Hybrid

  18. Natural and fire-induced soil water repellency in a Portugese Shrubland

    NARCIS (Netherlands)

    Stoof, C.R.; Moore, D.; Ritsema, C.J.; Dekker, L.W.

    2011-01-01

    Post-fire land degradation is often attributed to fire-induced soil water repellency, despite the fact that soil water repellency is a natural phenomenon in many soils and is therefore not necessarily caused by fire. To improve our understanding of the role of soil water repellency in causing

  19. Night driving assistance system based on spatial perspective approach

    Science.gov (United States)

    Poh, Chung-Kiak; Poh, Chung-How

    2004-10-01

    In this paper we put forward and evaluate a near real-time night driving assistance system intended for use in land vehicles (cars in particular) to help with T-junctions crossing at night. The onboard system of the host vehicle computes the remaining distance between itself and the nearest approaching vehicle using spatial perspective method. The algorithm evaluates the interspacing of the incoming vehicle's headlights. This allows the distance-to-contact to be determined or estimated. This work emphasises techniques to obtain the required image quality for distance sensing. The image quality was achieved when work was focused primarily at the hardware levels. With polaroids in place, the acquired images show that the headlight signals are clearly distinguishable from other ambient lights. This significantly simplifies image processing. Road-testing shows rather promising results. The system can be generalised to intersection settings, prevent rear-front collisions and may be extended for daytime applications with the introduction of virtual references.

  20. Transfer color to night vision images

    Institute of Scientific and Technical Information of China (English)

    Shaoyuan Sun; Zhongliang Jing; Gang Liu; Zhenhua Li

    2005-01-01

    @@ Natural color appearance is the key problem of color night vision field. In this paper, the color mood of daytime color image is transferred to the monochromic night vision image. This method gives the night image a natural color appearance. For each pixel in the night vision image, the best matching pixel in the color image is found based on texture similarity measure. Entropy, energy, contrast, homogeneity, and correlation features based on co-occurrence matrix are combined as texture similarity measure to find the corresponding pixels between the two images. We use a genetic algorithm (GA) to find the optimistic weighting factors assigned to the five different features. GA is also employed in searching the matching pixels to make the color transfer algorithm faster. When the best matching pixel in the color image is found, the chromaticity values are transferred to the corresponding pixel of the night vision image. The experiment results demonstrate the efficiency of this natural color transfer technique.

  1. The Night Sky Spectrum of Xinglong Observatory: Changes from 2004 to 2015

    CERN Document Server

    Zhang, Ji-Cheng; Yan, Jing-Zhi; Kumar, Yerra Bharat; Li, Hong-Bin; Gao, Dong-Yang; Jiang, Xiao-Jun

    2016-01-01

    We present spectroscopic measurements on the night sky of Xinglong Observatory for a period of 12 years from 2004 to 2015. The spectra were obtained on moonless clear nights using the OMR spectrograph mounted on a 2.16-m reflector with a wavelength coverage of 4000-7000A. The night sky spectrum shows the presence of emission lines from Hg I and Na I due to local artificial sources, along with the atmospheric emission lines, i.e., O I and OH molecules, indicating the existence of light pollution. We have monitored the night sky brightness during the whole night and found some decrement in the sky brightness with time, but the change is not significant. Also, we monitored the light pollution level in different azimuthal directions and found that the influence of light pollution from the direction of Beijing is stronger compared with that from the direction of Tangshan and other areas. An analysis of night sky spectra for the entire data set suggested that the zenith sky brightness of Xinglong Observatory has br...

  2. Palavra do corpo: confluência de linguagens em Night Journey Body word: language confluence in Night Journey

    Directory of Open Access Journals (Sweden)

    Aguinaldo Moreira de Souza

    2001-01-01

    Full Text Available Trata-se de um exercício de leitura da coreografia Night Journey (1947, de Martha Graham, como reinvenção do texto de Édipo rei (século IV a. C., de Sófocles. Pretende-se esboçar um estudo em que se evidenciem os processos interartísticos entre literatura e dança.The text consists in an exercise of interpretation of Martha Graham's choreography Night Journey (1947 as a recreation of Sophocles'Oedipus Rex (4th Century B.C.. The aim is to sketch a study in which the inter-artistic processes between literature and dance are brought to light.

  3. The GLOBE at Night Campaign: Promoting Dark Skies Awareness Beyond IYA2009

    Science.gov (United States)

    Walker, Constance E.

    2010-01-01

    One of the most productive programs in the IYA2009 Dark Skies Awareness Cornerstone Project has been GLOBE at Night. The GLOBE at Night program has endeavored to promote social awareness of the dark sky by getting the general public to measure light pollution and submit results on-line. During IYA2009 alone, over 15,700 measurements from 70 countries were contributed during the 2-week campaign period. That amount is twice the number of measurements on average from previous years. The GLOBE at Night website explains clearly the simple-to-participate-in 5 step program and offers background information and interactive games on key concepts. The program has been expanded to include trainings of the general public, but especially educators in schools, museums and science centers, in unique ways. Education kits for Dark Skies Awareness have been distributed at these training workshops. The kit includes material for a light shielding demonstration, a digital Sky Quality Meter and Dark Skies Ranger Activities. The activities are on how unshielded light wastes energy, how light pollution affects wildlife and how you can participate in a citizen-science star-hunt like GLOBE at Night. In addition, projects are being developed for what to do with the data once it is taken. There were particularly spirited and creative GLOBE at Night campaigns around the world in 2009. One such "poster child” was carried out by 6500 students in northern Indiana. The students produced 3,391 GLOBE at Night measurements. To visualize the magnitudes of dark sky lost to light pollution, these students removed over 12,000 of the 35,000 stacked LEGO blocks that represented an ideal night sky across the school district. The presentation will provide an update with lessons learned, describe how people can become involved and take a look ahead at the program's sustainability. For further information, visit www.globe.gov/globeatnight.

  4. Organization and management of ATLAS nightly builds

    Science.gov (United States)

    Luehring, F.; Obreshkov, E.; Quarrie, D.; Rybkine, G.; Undrus, A.

    2010-04-01

    The automated multi-platform software nightly build system is a major component in the ATLAS collaborative software organization, validation and code approval schemes. Code developers from ATLAS participating Institutes spread all around the world use about 30 branches of nightly releases for testing new packages, verification of patches to existing software, and migration to new platforms and compilers. The nightly releases lead up to, and are the basis of, stable software releases used for data processing worldwide. The ATLAS nightly builds are managed by the fully automated NICOS framework on the computing farm with 44 powerful multiprocessor nodes. The ATN test tool is embedded within the nightly system and provides results shortly after full compilations complete. Other test frameworks are synchronized with NICOS jobs and run larger scale validation jobs using the nightly releases. NICOS web pages dynamically provide information about the progress and results of the builds. For faster feedback, e-mail notifications about nightly releases problems are automatically distributed to the developers responsible.

  5. Effect of carbohydrates and night temperature on night respiration in rice.

    Science.gov (United States)

    Peraudeau, Sébastien; Lafarge, Tanguy; Roques, Sandrine; Quiñones, Cherryl O; Clement-Vidal, Anne; Ouwerkerk, Pieter B F; Van Rie, Jeroen; Fabre, Denis; Jagadish, Krishna S V; Dingkuhn, Michael

    2015-07-01

    Global warming causes night temperature (NT) to increase faster than day temperature in the tropics. According to crop growth models, respiration incurs a loss of 40-60% of photosynthate. The thermal sensitivity of night respiration (R(n)) will thus reduce biomass. Instantaneous and acclimated effects of NT on R(n) of leaves and seedlings of two rice cultivars having a variable level of carbohydrates, induced by exposure to different light intensity on the previous day, were investigated. Experiments were conducted in a greenhouse and growth chambers, with R(n) measured on the youngest fully expanded leaves or whole seedlings. Dry weight-based R(n) was 2.6-fold greater for seedlings than for leaves. Leaf R(n) was linearly related to starch (positive intercept) and soluble sugar concentration (zero intercept). Increased NT caused higher R(n) at a given carbohydrate concentration. The change of R(n) at NT increasing from 21 °C to 31 °C was 2.4-fold for the instantaneous response but 1.2- to 1.7-fold after acclimation. The maintenance component of R(n) (R(m)'), estimated by assimilate starvation, averaged 28% in seedlings and 34% in leaves, with no significant thermal effect on this ratio. The acclimated effect of increased NT on R(m)' across experiments was 1.5-fold for a 10 °C increase in NT. No cultivar differences were observed in R(n) or R(m)' responses. The results suggest that the commonly used Q10=2 rule overestimates thermal response of respiration, and R(n) largely depends on assimilate resources.

  6. Night sky a falcon field guide

    CERN Document Server

    Nigro, Nicholas

    2012-01-01

    Night Sky: A Falcon Field Guide covers both summer and winter constellations, planets, and stars found in the northern hemisphere. Conveniently sized to fit in a pocket and featuring detailed photographs, this informative guide makes it easy to identify objects in the night sky even from one's own backyard. From information on optimal weather conditions, preferred viewing locations, and how to use key tools of the trade, this handbook will help you adeptly navigate to and fro the vast and dynamic nighttime skies, and you'll fast recognize that the night sky's the limit.

  7. Exponential increase of publications related to soil water repellency

    NARCIS (Netherlands)

    Dekker, L.W.; Oostindie, K.; Ritsema, C.J.

    2005-01-01

    Soil water repellency is much more wide-spread than formerly thought. During the last decades, it has been a topic of study for soil scientists and hydrologists in at least 21 States of the USA, in Canada, Australia, New Zealand, Mexico, Colombia, Chile, Congo, Nepal, India, Hong Kong, Taiwan, China

  8. Repelling periodic points of given periods of rational functions

    Institute of Scientific and Technical Information of China (English)

    CHANG Jianming; FANG Mingliang

    2006-01-01

    Let R(z) be a rational function of degree d ≥ 2. Then R(z) has at least one repelling periodic point of given period k ≥ 2, unless k = 4 and d=2, or k= 3 and d ≤ 3, or k=2 and d≤8. Examples show that all exceptional cases occur.

  9. Olfactory responses to attractants and repellents in tsetse

    NARCIS (Netherlands)

    Voskamp, KE; Everaarts, E; Den Otter, CJ

    1999-01-01

    The aims of this study were to investigate how antennal olfactory cells of tsetse (Diptera: Glossinidae) code odour quality and how they are able to discriminate between attractive and repellent odours. For Glossina pallidipes Austen, a survey is presented of the cells' responses to attractive (1-oc

  10. Visible NearInfrared Spectroscopy Predicts Water Repellency in Soil

    DEFF Research Database (Denmark)

    Hermansen, Cecilie; Møldrup, Per; Clothier, Brent;

    Soil water repellency (SWR) is a property which has consequences for agricultural water management. The SWR is caused by hydrophobic organic coatings on mineral particles and the severity is highly depending on the organic matter quantity and quality and on the moisture status of the soil...

  11. An autopsy case of fatal repellent air freshener poisoning.

    Science.gov (United States)

    Hitosugi, Masahito; Tsukada, Chie; Yamauchi, Shinobu; Matsushima, Kazumi; Furukawa, Satoshi; Morita, Satomu; Nagai, Toshiaki

    2015-09-01

    We describe a first fatal case of repellent air freshener ingestion. A 79-year-old Japanese man with Alzheimer-type senile dementia orally ingested repellent air freshener containing three surfactants: polyoxyethylene 9-lauryl ether, polyoxyethylene (40) hydrogenated castor oil, and lauric acid amidopropyl amine oxide (weight ratio of 1.3%). About 1h after the collapse, he was in cardiopulmonary arrest and subsequently died 10h after his arrival. The forensic autopsy performed 5.5h after death revealed the 380ml of stomach contents with a strong mint perfume identical to that of the repellent air freshener and the findings of acute death. Toxicologically, 9.1μg/ml and 558.2μg/ml of polyoxyethylene 9-lauryl ether were detected from the serum and stomach contents taken at autopsy. Generally, ingestion of anionic or non-ionic surfactants have been considered as safe. However, because the patient suffered from cardiac insufficiency with a low dose of repellent air freshener ingestion, medical staff members must evaluate the elderly patient for cardiac and circulatory problems regardless of the ingested dose. Not only medical and nursing staff members, but also families who are obliged to care for elderly persons must be vigilant to prevent accidental ingestion of toxic substances generally used in the household.

  12. Insect Repellents: Modulators of mosquito odorant receptor activity

    Science.gov (United States)

    Mosquitoes vector numerous pathogens that cause diseases including malaria, yellow fever, dengue fever and chikungunya. DEET, IR3535, Picaridin and 2-undecanone are insect repellents that are used to prevent interactions between humans and a broad array of disease vectors including mosquitoes. While...

  13. Exponential increase of publications related to soil water repellency

    NARCIS (Netherlands)

    Dekker, L.W.; Oostindie, K.; Ritsema, C.J.

    2005-01-01

    Soil water repellency is much more wide-spread than formerly thought. During the last decades, it has been a topic of study for soil scientists and hydrologists in at least 21 States of the USA, in Canada, Australia, New Zealand, Mexico, Colombia, Chile, Congo, Nepal, India, Hong Kong, Taiwan,

  14. Soil surfactant stops water repellency and preferential flow paths

    NARCIS (Netherlands)

    Oostindie, K.; Dekker, L.W.; Wesseling, J.G.; Ritsema, C.J.

    2008-01-01

    This study reports the effects of a soil surfactant on reduction and prevention of water repellency and preferential flow paths in a sandy soil of a golf course fairway, located at Bosch en Duin near Utrecht, the Netherlands. The golf course is constructed on inland dunes composed of fine sand with

  15. The role of repellents and hydrophobins in Ustilago maydis

    NARCIS (Netherlands)

    Teertstra, W.R.

    2009-01-01

    Ustilago maydis is an important model organism to study fungal pathogenicity. U. maydis can grow yeast-like and filamentous. In the latter form this fungus infects maize. In my Thesis the expression and function of hydrophobins and repellents of U. maydis were studied. Hydrophobins are produced by f

  16. Engineering Characteristics of Chemically Treated Water-Repellent Kaolin.

    Science.gov (United States)

    Choi, Youngmin; Choo, Hyunwook; Yun, Tae Sup; Lee, Changho; Lee, Woojin

    2016-12-02

    Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO) ranging from 0.5% to 10% by weight. As the CO increases, the specific gravity of treated clay tends to decrease, whereas the total organic carbon content of the treated clay tends to increase. The soil-water contact angle increases with an increase in CO until CO = 2.5%, and then maintains an almost constant value (≈134.0°). Resistance to water infiltration is improved by organosilane treatment under low hydrostatic pressure. However, water infiltration resistance under high hydrostatic pressure is reduced or exacerbated to the level of untreated clay. The maximum compacted dry weight density decreases with increasing CO. As the CO increases, the small strain shear modulus increases, whereas the effect of organosilane treatment on the constrained modulus is minimal. The results indicate that water-repellent kaolin clay possesses excellent engineering characteristics for a landfill cover material.

  17. Engineering Characteristics of Chemically Treated Water-Repellent Kaolin

    Directory of Open Access Journals (Sweden)

    Youngmin Choi

    2016-12-01

    Full Text Available Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO ranging from 0.5% to 10% by weight. As the CO increases, the specific gravity of treated clay tends to decrease, whereas the total organic carbon content of the treated clay tends to increase. The soil-water contact angle increases with an increase in CO until CO = 2.5%, and then maintains an almost constant value (≈134.0°. Resistance to water infiltration is improved by organosilane treatment under low hydrostatic pressure. However, water infiltration resistance under high hydrostatic pressure is reduced or exacerbated to the level of untreated clay. The maximum compacted dry weight density decreases with increasing CO. As the CO increases, the small strain shear modulus increases, whereas the effect of organosilane treatment on the constrained modulus is minimal. The results indicate that water-repellent kaolin clay possesses excellent engineering characteristics for a landfill cover material.

  18. Water repellency of two forest soils after biochar addition

    Science.gov (United States)

    D. S. Page-Dumroese; P. R. Robichaud; R. E. Brown; J. M. Tirocke

    2015-01-01

    Practical application of black carbon (biochar) to improve forest soil may be limited because biochar is hydrophobic. In a laboratory, we tested the water repellency of biochar application (mixed or surface applied) to two forest soils of varying texture (a granitic coarse-textured Inceptisol and an ash cap fine-textured Andisol) at four different application rates (0...

  19. The role of repellents and hydrophobins in Ustilago maydis

    NARCIS (Netherlands)

    Teertstra, W.R.

    2009-01-01

    Ustilago maydis is an important model organism to study fungal pathogenicity. U. maydis can grow yeast-like and filamentous. In the latter form this fungus infects maize. In my Thesis the expression and function of hydrophobins and repellents of U. maydis were studied. Hydrophobins are produced by f

  20. Causes and consequences of fire-induced soil water repellency

    Science.gov (United States)

    Letey, J.

    2001-10-01

    A wettable surface layer overlying a water-repellent layer is commonly observed following a fire on a watershed. High surface temperatures burn off organic materials and create vapours that move downward in response to a temperature gradient and then condense on soil particles causing them to become water repellent. Water-repellent soils have a positive water entry pressure hp that must be exceeded or all the water will runoff. Water ponding depths ho that exceeds hp will cause infiltration, but the profile is not completely wetted. Infiltration rate and soil wetting increase as the value of ho/hp increases. The consequence is very high runoff, which also contributes to high erosion on fire-induced water-repellent soils during rain storms. Grass establishment is impaired by seeds being eroded and lack of soil water for seeds that do remain and germinate. Extrapolation of these general findings to catchment or watershed scales is difficult because of the very high temporal and spatial variabilities that occur in the field.

  1. Fire-induced water-repellent soils, an annotated bibliography

    Science.gov (United States)

    Kalendovsky, M.A.; Cannon, S.H.

    1997-01-01

    The development and nature of water-repellent, or hydrophobic, soils are important issues in evaluating hillslope response to fire. The following annotated bibliography was compiled to consolidate existing published research on the topic. Emphasis was placed on the types, causes, effects and measurement techniques of water repellency, particularly with respect to wildfires and prescribed burns. Each annotation includes a general summary of the respective publication, as well as highlights of interest to this focus. Although some references on the development of water repellency without fires, the chemistry of hydrophobic substances, and remediation of water-repellent conditions are included, coverage of these topics is not intended to be comprehensive. To develop this database, the GeoRef, Agricola, and Water Resources Abstracts databases were searched for appropriate references, and the bibliographies of each reference were then reviewed for additional entries. Additional references will be added to this bibliography as they become available. The annotated bibliography can be accessed on the Web at http://geohazards.cr.usgs.gov/html_files/landslides/ofr97-720/biblio.html. A database consisting of the references and keywords is available through a link at the above address. This database was compiled using EndNote2 plus software by Niles and Associates, and is necessary to search the database.

  2. A Green Route for Substrate-Independent Oil-Repellent Coatings

    Science.gov (United States)

    Xu, Li-Ping; Han, Da; Wu, Xiuwen; Zhang, Qingqing; Zhang, Xueji; Wang, Shutao

    2016-11-01

    Oil repellent surface have lots of practical applications in many fields. Current oil repellent coating may suffer from limited liquid repellency to oils or environmental risks. In this work, we report an eco-friendly ‘green’ processes for preparing oil-repellent surface using a renewable and environmentally benign bioresource alginate. The oil-repellent coating was prepared by a two-step surface coating technique and showed stable oil repellency to many kinds of oils. The fabrication process was very simple with no need for special equipment, and this approach can be successfully employed to various substrates with different compositions, sizes and shapes, or even substrate-independent oil-repellent materials. The as-prepared coating of calcium alginate may have a good future in packaging oil-containing products and foods.

  3. Laboratory evaluation of four commercial repellents against larval Leptotrombidium deliense (Acari: Trombiculidae).

    Science.gov (United States)

    Hanifah, Azima Laili; Ismail, Siti Hazar Awang; Ming, Ho Tze

    2010-09-01

    Four commercial repellents were evaluated in the laboratory against Leptotrombidium deliense chiggers. Both in vitro and in vivo methods were used to determine repellency of the compounds. The repellents were Kellis (containing citronella oil, jojoba oil and tea tree oil), Kaps (containing citronella oil), BioZ (containing citronella oil, geranium oil and lemon grass oil) and Off (containing DEET). The combination of three active ingredients: citronella oil, geranium oil, lemon grass oil gave the highest repellency (87%) followed by DEET (84%). In vitro repellencies ranged from 73% to 87%. There was no significant difference between the four products. All the repellents had 100% in vivo repellency compared to 41-57% for the controls.

  4. Rotating night shift work, sleep quality, selected lifestyle factors and prolactin concentration in nurses and midwives.

    Science.gov (United States)

    Bukowska, Agnieszka; Sobala, Wojciech; Peplonska, Beata

    2015-04-01

    The pattern of secretion of many hormones, including prolactin, is dependent on the circadian rhythm. Night shift work involves exposure to artificial light at night and sleep deficiency, which in turn can affect prolactin synthesis. The aim of this study was to evaluate a possible association between night shift work characteristics, sleep quality, lifestyle factors and prolactin concentration, using data from a cross-sectional study of nurses and midwives. A cross-sectional study was conducted among 327 nurses and midwives currently working on rotating night shifts, and 330 nurses and midwives working during the day (aged 40-60 years) (388 premenopausal and 269 postmenopausal). Information about night shift work characteristics, lifestyle, reproductive factors, sleep pattern and other covariates was collected through a face-to-face interview, and from a one-week work and sleep diary completed by the subjects. Weight and height were measured. Prolactin concentration was measured in the morning blood sample using the electrochemiluminesence immunoassay method. Associations were analyzed using linear regression models adjusted for important confounders. Analyses were carried out separately in pre- and postmenopausal women. None of the night shift work or sleep characteristics was significantly associated with prolactin concentration. Prolactin concentration was significantly (p prolactin among premenopausal women, but inversely among postmenopausal. Age was related to prolactin among postmenopausal women only. Our study indicates that rotating night shift work is not associated with prolactin concentration. Smoking, parity, time of blood collection and age among postmenopausal women were significant determinants of prolactin.

  5. How a small enterprise improved the conditions of night and shift work using local resources.

    Science.gov (United States)

    Khai, T T; Kawakami, T; Kogi, K

    2001-12-01

    A small oxygen factory in Cantho Province located in the Mekong Delta Area in the southern part of Vietnam was studied to provide practical support measures to improve night and shift work. A direct observation study and a fatigue symptom survey during the work were conducted. The factory applied discontinuous two-shift systems in two teams. Depending on customers' demands, they frequently prolonged oxygen production until midnight. The study results showed work-related risks such as carrying heavy oxygen cylinders, workers' sleepiness during the night work, and increased fatigue feelings among production operators. Based on the study results, better strategies for night and shift work schedules such as regular work hours minimizing overtime and night work were discussed with the managers and workers. A follow-up visit three months later confirmed many improvements undertaken in the factory. Better work arrangements for night and shift workers were made including local lighting, resting corners, filling the height gaps on the work floors, and clear work instructions. Prolonged mid-night shift was stopped. It was concluded that local small enterprises in Vietnam have much potential to improve their conditions of shift and night work once practical support measures based on their local practice is given.

  6. LARVICIDAL POTENTIAL AND MOSQUITO REPELLENT ACTIVITY OF CASSIA MIMOSOIDES EXTRACTS.

    Science.gov (United States)

    Alayo, M A; Femi-Oyewo, M N; Bakre, L G; Fashina, A O

    2015-07-01

    This study aims to investigate larvicidal activities of extracts of Cassia mimosoides leaves and pods as a potential agent in vector control of malaria and to evaluate repellent effect against Anopheles gambiae mosquito of the extract formulated in an aqueous cream base. Petroleum spirit, ethanol, water and dichloromethane extracts were tested against third and fourth instar Anopheles gambiae larvae. The petroleum extract was formulated in an aqueous cream base and repellency determined using N-N-diethyl-m-toluamide (DEET) as control. Phytochemical analysis showed the presence of saponins, tannins, anthraquinones, steroids, and flavonoids but absence of cardiac glycosides and alkaloids in powdered C. mimosoides. A dose related response was observed in the mortality rate of the extracts, with 2 mg/ml petroleum ether and dichloromethane extracts achieving 100 % mortality. Larvicidal activity of extracts based on LC50 values was petroleum ether > dichloromethane > ethanol > water. The formulated petroleum ether extract cream had a characteristic odor, hard and smooth texture, skin feeling of smoothness, ease of application by rubbing, easy removal using soap and water, non-irritating effect on skin and an acceptable pH value. The cream containing 2%-6% (w/w) extract and control achieved 100% repellency against mosquitoes after an exposure time of 5 minutes. There was a linear relationship between percent concentration of plant extract in the cream samples and repellent activity. These results suggest that crude extracts of C. mimosoides can be developed as eco-friendly larvicide and mosquito repellent and encourage further effort to investigate the bioactive compounds in the extracts.

  7. Optimal management of night eating syndrome: challenges and solutions

    Directory of Open Access Journals (Sweden)

    Kucukgoncu S

    2015-03-01

    Full Text Available Suat Kucukgoncu, Margaretta Midura, Cenk Tek Department of Psychiatry, Yale University, New Haven, CT, USA Abstract: Night Eating Syndrome (NES is a unique disorder characterized by a delayed pattern of food intake in which recurrent episodes of nocturnal eating and/or excessive food consumption occur after the evening meal. NES is a clinically important disorder due to its relationship to obesity, its association with other psychiatric disorders, and problems concerning sleep. However, NES often goes unrecognized by both health professionals and patients. The lack of knowledge regarding NES in clinical settings may lead to inadequate diagnoses and inappropriate treatment approaches. Therefore, the proper diagnosis of NES is the most important issue when identifying NES and providing treatment for this disorder. Clinical assessment tools such as the Night Eating Questionnaire may help health professionals working with populations vulnerable to NES. Although NES treatment studies are still in their infancy, antidepressant treatments and psychological therapies can be used for optimal management of patients with NES. Other treatment options such as melatonergic medications, light therapy, and the anticonvulsant topiramate also hold promise as future treatment options. The purpose of this review is to provide a summary of NES, including its diagnosis, comorbidities, and treatment approaches. Possible challenges addressing patients with NES and management options are also discussed. Keywords: night eating, obesity, psychiatric disorders, weight, depression

  8. Modern night vision goggles for advanced infantry applications

    Science.gov (United States)

    Estrera, Joseph P.; Ostromek, Timothy E.; Isbell, Wayne; Bacarella, Antonio V.

    2003-09-01

    Northrop Grumman Electro-Optical Systems (NGEOS) has concentrated in recent years on the development of advanced night vision goggle (NVG) systems. These NVGs developments concentrate on past operational deficiencies such as high light/bright source conditions during military operations in urban terrain (MOUT), poor individual movement technique (IMT) infantry operations, and obscured battlefield and reduced weather conditions. The first area of NVG advancement involves direct image intensifier (I2) replacement involving automatic gated power supply technology for wide dynamic NVG operation and advanced Generation III halo free I2 technology for reduction of NVG image halo and "blooming" artifacts. The second significant development area is NVG individual movement technique (IMT) deficiencies such as reduced field of view, reduced depth perception, center of gravity problems, and limited operation flexibility. These issues of NVG IMT have resulted in the development of an IMT enhanced night vision goggle for the U.S. Army's enhanced night vision goggle (ENVG). Finally, Northrop Grumman EOS is developing a NVG with the capability of producing optimized real-time image fusion from an image intensified sensor and uncooled long wavelength infrared (LWIR) sensor. This new technology allows for optimum imaging in battlefield obscured and laser polluted environment. These image fusion NVG development efforts have concentrated on both optical overlay image fusion and digital image fusion. This paper will compare and contrast these two types of image fusion technologies.

  9. Starry Nights: The Great World Wide Star Count

    Science.gov (United States)

    Ward, Dennis; Meymaris, K.; Henderson, S.; Johnson, R.

    2008-05-01

    The Great World Wide Star Count is an international field campaign encouraging participants to go outside, look skyward after dark, count the stars they see in certain constellations, and report what they see online. This Windows to the Universe citizen science event is designed to raise awareness about light pollution and the night sky as well as promote learning in astronomy. Star Count benefits from the current excitement in citizen science. The 2007 pilot effort included 15 nights for observations in October & November. Utilizing the international networking capabilities of Windows to the Universe, Star Count is able to engage people from all countries. Data collection and online reporting is designed to be simple and user-friendly for citizen scientists of all ages. The collected data is available online in a variety of formats 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 our results and demonstrate how students and scientists worldwide can explore and analyze the data from the of the 2007 campaign. We will discuss how the Star Count team planned and executed the project in such a way that non-astronomers were able to make valid and useful contributions. We will also discuss lessons learned and best practices based on this inaugural campaign, as well as our plans for the future, including IYA 2009.

  10. Wet-dry cycles effect on ash water repellency. A laboratory experiment.

    Science.gov (United States)

    Pereira, Paulo; Cerdà, Artemi; Oliva, Marc; Mataix, Jorge; Jordán, Antonio

    2014-05-01

    In the immediate period after the fire, the ash layer has a strong influence on soil hydrological processes, as runoff, infiltration and erosion. Ash is very dynamic in the space and time. Until the first rainfall periods, ash is (re)distributed by the wind. After it can cover the soil surface, infiltrate or transported to other areas by water transport (Pereira et al., 2013a, b). This will have strong implications on nutrient redistribution and vegetation recovery. Ash layer may affect soil water repellency in different ways, depending on fire severity, soil properties and vegetation. Ash produced at low temperatures after low-severity burning is usually hydrophobic (Bodi et al., 2011, 2012). Wet-dry cycles have implications on ash physical and chemical properties, changing their effects in space and time. The aim of this study is to analyse the effects of fire temperature and severity on ash water repellency. Pinus sylvestris needles were collected in a Lithuania forest in Dzukija National Park (53º 54' N and 24º 22' E), transported to laboratory and washed with deionized water to remove soil particles and other residues. Needle samples were dried during 24 hours and exposed to different temperatures: 200, 300, 400 and 500 ºC, during 2 hours. Ash colour was analysed according to the Munsell Soil Color charts. Ash was black (10 YR 2/1) at 200 ºC, very dark grey (10YR 3/1) at 300 ºC, gray (10YR 5/1) at 400 ºC and light gray (10YR 7/1) at 500 ºC. Ten samples of ash released after each treatment were placed in plastic dishes (50 mm in diameter) in an amount enough to form a 5 mm thick layer, and ash water repellency was measured according to the Water Drop Penetration Test. Later, ash was carefully wetted with 15 ml of deionized water and placed in an oven during 4 days (96 hours), as in Bodí et al. (2012). This procedure was repeated 5 times in order to observe the effects of wet-dry cycles in ash water repellency. The results showed significant differences

  11. Evolution of the ATLAS Nightly Build System

    CERN Document Server

    Undrus, A; The ATLAS collaboration

    2012-01-01

    For over 10 years of development the ATLAS Nightly Build System has evolved into a factory for automatic release production and grid distribution. The numerous branches of ATLAS releases provide vast opportunities for testing new packages, verification of patches to existing software, and migration to new platforms and compilers for ATLAS code that currently contains ~2200 packages with 4 million C++ and 1.4 million python scripting lines written by ~1000 developers. The nightly releases lead up to stable releases used for data processing and analysis worldwide. The ATLAS Nightly System is managed by the NICOS control tool on the ATLAS Build Farm. The ATN testing framework runs unit and integration tests for the nightly releases.

  12. Smartphones May Hinder a Good Night's Sleep

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_161924.html Smartphones May Hinder a Good Night's Sleep Study suggests ... sleep, it might be wise to give your smartphone a rest from time to time. New research ...

  13. Evolution of the ATLAS Nightly Build System

    CERN Document Server

    Undrus, A

    2012-01-01

    The ATLAS Nightly Build System is a major component in the ATLAS collaborative software organization, validation, and code approval scheme. For over 10 years of development it has evolved into a factory for automatic release production and grid distribution. The 50 multi-platform branches of ATLAS releases provide vast opportunities for testing new packages, verification of patches to existing software, and migration to new platforms and compilers for ATLAS code that currently contains 2200 packages with 4 million C++ and 1.4 million python scripting lines written by about 1000 developers. Recent development was focused on the integration of ATLAS Nightly Builds and Installation systems. The nightly releases are distributed and validated and some are transformed into stable releases used for data processing worldwide. The ATLAS Nightly System is managed by the NICOS control tool on a computing farm with 50 powerful multiprocessor nodes. NICOS provides the fully automated framework for the release builds, test...

  14. TBT recommends : Courtney Pine. Hansa disco night

    Index Scriptorium Estoniae

    2005-01-01

    Inglise jazzsaksofonisti Courtney Pine heliplaadi "Resistance" esitluskontserdist 15. dets. Rock Cafés Tallinnas. Inglise laulja Chris Norman läti ansamblitega üritusel "Hansa disco night Nr.4" 9. dets. Kipsala Hallis Riias

  15. TBT recommends : Courtney Pine. Hansa disco night

    Index Scriptorium Estoniae

    2005-01-01

    Inglise jazzsaksofonisti Courtney Pine heliplaadi "Resistance" esitluskontserdist 15. dets. Rock Cafés Tallinnas. Inglise laulja Chris Norman läti ansamblitega üritusel "Hansa disco night Nr.4" 9. dets. Kipsala Hallis Riias

  16. Night sky photometry and spectroscopy performed at the Vienna University Observatory

    CERN Document Server

    Puschnig, Johannes; Uttenthaler, Stefan

    2013-01-01

    We present night sky brightness measurements performed at the Vienna University Observatory and at the Leopold-Figl-Observatorium fuer Astrophysik, which is located about 35km to the southwest of Vienna. The measurements have been performed with Sky Quality Meters made by Unihedron. They cover a time span of roughly one year and have been carried out every night, yielding a night sky brightness value every 7 seconds and thus delivering a large amount of data. In this paper, the level of light pollution at the Vienna University Observatory, which ranges from 15 to 19.25 magnitudes per square arcsecond, is presented for the very first time in a systematic way. We discuss the influence of different environmental conditions on the night sky brightness and implications for human vision. We show that the circalunar rhythm of night sky brightness is extinguished at our observatory due to light pollution. Additionally, we present spectra of the night sky in Vienna, taken with a 0.8m telescope. The goal of these spect...

  17. Night sky photometry and spectroscopy performed at the Vienna University Observatory

    Science.gov (United States)

    Puschnig, Johannes; Posch, Thomas; Uttenthaler, Stefan

    2014-05-01

    We present night sky brightness measurements performed at the Vienna University Observatory and at the Leopold-Figl-Observatorium für Astrophysik, which is located about 35 km to the southwest of Vienna. The measurements have been performed with Sky Quality Meters made by Unihedron. They cover a time span of roughly one year and have been carried out every night, yielding a luminance value every 7 s and thus delivering a large amount of data. In this paper, the level of skyglow in Vienna, which ranges from 15 to 19.25 magSQM arcsec-2 is presented for the very first time in a systematic way. We discuss the influence of different environmental conditions on the night sky brightness and implications for human vision. We show that the circalunar rhythm of night sky brightness is almost extinguished at our observatory due to light pollution. Additionally, we present spectra of the night sky in Vienna, taken with a 0.8 m telescope. The goal of these spectroscopic measurements was to identify the main types of light sources and the spectral lines which cause the skyglow in Vienna. It turned out that fluorescent lamps are responsible for the strongest lines of the night sky above Vienna (e.g. lines at 546 nm and at 611 nm).

  18. Night cough and general practice research.

    Science.gov (United States)

    Toop, L J; Howie, J G; Paxton, F M

    1986-02-01

    Thirty-four children, aged between three and nine years, presenting with nocturnal cough, were studied on successive nights using an automatic voice activated tape recorder system. Children with a family history of atopy coughed significantly more than children without such a family history. A wide variation in cough frequency was found both between and within subjects. No effects of treatment on cough frequency were demonstrated. Some of the physiological and pathological mechanisms underlying night cough are discussed.

  19. Work at night and breast cancer - report on evidence-based options for preventive actions

    DEFF Research Database (Denmark)

    Bonde, Jens Peter; Hansen, Johnni; Kolstad, Henrik A.

    2012-01-01

    actions, 16 researchers in basic, epidemiological and applied sciences convened at a workshop in Copenhagen 26-27 October 2011. This paper summarizes the evidence from epidemiological and experimental studies and presents possible recommendations for prevention of the effects of night work on breast...... cancer. Among those studies that quantified duration of shift work, there were statistically significant elevations in risk only after about 20 years working night shift. It is unclear from these studies whether or not there is a modest but real elevated risk for shorter durations. Hence, restriction...... by suppression of melatonin secretion. Work during the night is widespread worldwide. To provide additional evidence-based recommendations on prevention of diseases related to night shift work, large studies on the impact of various shift schedules and type of light on circadian rhythms need to be conducted...

  20. Investigative Poetics: In (night-Light of Akilah Oliver

    Directory of Open Access Journals (Sweden)

    Feliz Molina

    2011-06-01

    Full Text Available “Flesh Memory” according to Akilah Oliver is "that which my body recalls [...] everything has to do with the task of remembrance and its narrative reinvention [...] I was always translating an idea of the world as it presented itself at any given time. To write was a choice about how to be seen, how to enter the world as translator, actor, participant, in the dialogues that apparently made the real 'real'" (Levitsky. Flesh. Memory. The stuff some poems are made from. The stuff that gets abandoned, gleaned, and picked up by more flesh and memory. "My body, my life has always felt like a kaleidoscopic rip in the dominant fabric [...] has always been a dialogue with the impossible and the apparent” (Levitsky. The impossible-body or poet's body anticipates and performs (through language an irretrievable death.

  1. Insecticidal, repellent and fungicidal properties of novel trifluoromethylphenyl amides.

    Science.gov (United States)

    Tsikolia, Maia; Bernier, Ulrich R; Coy, Monique R; Chalaire, Katelyn C; Becnel, James J; Agramonte, Natasha M; Tabanca, Nurhayat; Wedge, David E; Clark, Gary G; Linthicum, Kenneth J; Swale, Daniel R; Bloomquist, Jeffrey R

    2013-09-01

    Twenty trifluoromethylphenyl amides were synthesized and evaluated as fungicides and as mosquito toxicants and repellents. Against Aedes aegypti larvae, N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-3,5-dinitrobenzamide (1e) was the most toxic compound (24 h LC50 1940 nM), while against adults N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-2,2,2-trifluoroacetamide (1c) was most active (24 h LD50 19.182 nM, 0.5 μL/insect). However, the 24 h LC50 and LD50 values of fipronil against Ae. aegypti larvae and adults were significantly lower: 13.55 nM and 0.787 × 10(-4) nM, respectively. Compound 1c was also active against Drosophila melanogaster adults with 24 h LC50 values of 5.6 and 4.9 μg/cm(2) for the Oregon-R and 1675 strains, respectively. Fipronil had LC50 values of 0.004 and 0.017 μg/cm(2) against the two strains of D. melanogaster, respectively. In repellency bioassays against female Ae. aegypti, 2,2,2-trifluoro-N-(2-(trifluoromethyl)phenyl)acetamide (4c) had the highest repellent potency with a minimum effective dosage (MED) of 0.039 μmol/cm(2) compared to DEET (MED of 0.091 μmol/cm(2)). Compound N-(2-(trifluoromethyl)phenyl)hexanamide (4a) had an MED of 0.091 μmol/cm(2) which was comparable to DEET. Compound 4c was the most potent fungicide against Phomopsis obscurans. Several trends were discerned between the structural configuration of these molecules and the effect of structural changes on toxicity and repellency. Para- or meta- trifluoromethylphenyl amides with an aromatic ring attached to the carbonyl carbon showed higher toxicity against Ae. aegypti larvae, than ortho- trifluoromethylphenyl amides. Ortho- trifluoromethylphenyl amides with trifluoromethyl or alkyl group attached to the carbonyl carbon produced higher repellent activity against female Ae. aegypti and Anopheles albimanus than meta- or para- trifluoromethylphenyl amides. The presence of 2,6-dichloro- substitution on the phenyl ring of the amide had an influence on larvicidal and repellent

  2. A Try to Import a New Basic Data for Fast Evaluation of Earthquake Hazards--Utilizing the DMSP/OLS Satellite Night-time Light Data%引入一种新型震害快速评估基础数据的尝试——DMSP/OLS卫星夜光数据的使用

    Institute of Scientific and Technical Information of China (English)

    刘双庆

    2012-01-01

    In order to analyze the feasibility of fast evaluation of the death induced by 4 M 〉 7.0 global earthquakes from L990 with DMSP/OLS data, in this paper the author makes best use of the three kinds of data resources, which are the night-time light data of latest twenty years from American DMSP/OLS, the model corresponding with the relation between night-time light strength and Chinese statistical spatial distribution of population, and the death rate model of strong earthquake based on population density. Through vectoring the official reported intensity map and population density transferred from the DMSP/OLS data and their spatial interaction area, the death of 4 earthquakes mentioned above are calculated and they are consisted with the fac;tual statistical result. Concretely, the evaluations of Turkey IZMIT and Taiwan Jiji earthquakes have few gaps opposite to the reality. The calculation of Wenehuan and Haiti are lower than the factual statistics, and the contradictions maybe due to the heavily seismic geological hazard in Wenchuan district and lack of protecting against and mitigating earthquake disasters in Haiti district respectively.%本文尝试性使用美国军事气象DMSP卫星20年来的夜光数据,并利用前人在夜光数据与中国人口统计分布的关系模型以及基于人员死亡率表示的地震生命易损性模型,分析国内外1990年来有影响的4次7级以上强地震的人员死亡情况.通过对正式公布的烈度图矢量化与通过DMSP/OLS夜光数据换算出的人口密度分布的空间相互覆盖情况,计算得出4次强地震理论计算的结果和实际人员死亡统计结果在一个数量级的误差范围内具有可信度。其中土耳其IZMIT市地震、中国台湾集集地震的计算结果比较吻合,而汶川地震与海地地震理论计算的结果比实际的偏小,这可能与汶川地震高烈度区地震地质灾害异常严重以及海地太子港地区缺乏抗震设防,房屋抗震性能薄弱有关。

  3. Let there be no light: the effect of bedside light on sleep quality and background electroencephalographic rhythms

    OpenAIRE

    Cho, Jounhong Ryan; Joo, Eun Yeon; Koo, Dae Lim; Hong, Seung Bong

    2013-01-01

    Objectives: Artificial lighting has been beneficial to society, but unnecessary light exposure at night may cause various health problems. We aimed to investigate how whole-night bedside light can affect sleep quality and brain activity. Patients and methods: Ten healthy sleepers underwent two polysomnography (PSG) sessions, one with the lights off and one with the lights on. PSG variables related to sleep quality were extracted and compared between lights-off and lights-on sleep. Sp...

  4. Supportive leadership in Swedish community night nursing.

    Science.gov (United States)

    Gustafsson, Christine; Fagerberg, Ingegerd; Asp, Margareta

    2010-10-01

    The aim of the present study was to examine the support night nurses' give to staff in community night nursing. Studies have shown that support given to staff is one of night registered nurses' (RNs') experiences of the meaning of caring. This support, that community RNs display for staff in night-time care, is sparsely described. All community night-duty nurses in a medium-sized municipal in Sweden participated in the present study. Thematic content analysis was used to analyse data from observations. The support given by RNs to staff is described using three themes: (1) a conditional supporting stance, (2) preparing propitious conditions for caring and (3) confidence in the abilities of individual staff members and adaptation to their individual needs. The results reveal that RNs consider support to staff in terms of nursing leadership. Out of 'concern for the staff' the RNs try to be there for them, which corresponds to nursing leadership. Such concern also arises from the RNs' awareness that by giving support to staff this affects the staffs' caring for older people. The current municipal social care organization of community nursing of older people in which RNs have extensive responsibilities with insufficient control, is a working condition with a risk for decreased quality of care and a high risk for work-related stress syndrome. © 2010 The Authors. Journal compilation © 2010 Blackwell Publishing Ltd.

  5. Studies toward the synthesis of the shark repellent pavoninin-5.

    Science.gov (United States)

    Williams, John R; Chai, Deping; Gong, Hua; Zhao, Wei; Wright, Dominic

    2002-12-01

    Sharks are the most dangerous predators of people in the sea, resulting in people being mauled and killed each year. A shark repellent could help to diminish this danger. The aglycone of the shark repellent pavoninin-5, (25R)-cholest-5-en-3beta,15alpha,26-triol (5a), was synthesized from diosgenin (9). Removing mercury from the Clemmensen reduction of 9 gave a higher yield of (25R)-cholest-5-en-3beta,16beta,26-triol, 10a, and was also more environmentally friendly. Attempted methods for the transposition of the C-16beta hydroxyl to the 15alpha position are described. A successful method for this transposition via the 15alpha-hydroxy-16-ketone, 8a, using the Barton deoxygenation reaction on the 16-alcohol 14b, is reported.

  6. Octanoic acid confers to royal jelly varroa-repellent properties

    Science.gov (United States)

    Nazzi, Francesco; Bortolomeazzi, Renzo; Della Vedova, Giorgio; Del Piccolo, Fabio; Annoscia, Desiderato; Milani, Norberto

    2009-02-01

    The mite Varroa destructor Anderson & Trueman is a parasite of the honeybee Apis mellifera L. and represents a major threat for apiculture in the Western world. Reproduction takes place only inside bee brood cells that are invaded just before sealing; drone cells are preferred over worker cells, whereas queen cells are not normally invaded. Lower incidence of mites in queen cells is at least partly due to the deterrent activity of royal jelly. In this study, the repellent properties of royal jelly were investigated using a lab bioassay. Chemical analysis showed that octanoic acid is a major volatile component of royal jelly; by contrast, the concentration is much lower in drone and worker larval food. Bioassays, carried out under lab conditions, demonstrated that octanoic acid is repellent to the mite. Field studies in bee colonies confirmed that the compound may interfere with the process of cell invasion by the mite.

  7. Insecticidal, Repellent and Fungicidal Properties of Novel Trifluoromethylphenyl Amides

    Science.gov (United States)

    2013-01-01

    Insecticidal, repellent and fungicidal properties of novel trifluoromethylphenyl amidesq Maia Tsikolia a,⇑, Ulrich R. Bernier a, Monique R. Coy a...Swale e, Jeffrey R. Bloomquist e aU.S. Department of Agriculture - Agricultural Research Service, Center for Medical, Agricultural , and Veterinary...dU.S. Department of Agriculture - Agricultural Research Service, Natural Products Utilization Research Unit, The University of Mississippi, University

  8. Facile Method to Prepare Superhydrophobic and Water Repellent Cellulosic Paper

    OpenAIRE

    Ioannis Karapanagiotis; Diana Grosu; Dimitra Aslanidou; Aifantis, Katerina E.

    2015-01-01

    Silica nanoparticles (7 nm) were dispersed in solutions of a silane/siloxane mixture. The dispersions were applied, by brush, on four types of paper: (i) modern, unprinted (blank) paper, (ii) modern paper where a text was printed using a common laser jet printer, (iii) a handmade paper sheet detached from an old book, and (iv) Japanese tissue paper. It is shown that superhydrophobicity and water repellency were achieved on the surface of the deposited films, when high particle concentrations ...

  9. Frequency of College Students' Night-Sky Watching Behaviors

    Science.gov (United States)

    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…

  10. 5 CFR 550.122 - Computation of night pay differential.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Computation of night pay differential... REGULATIONS PAY ADMINISTRATION (GENERAL) Premium Pay Night Pay § 550.122 Computation of night pay differential. (a) Absence on holidays or in travel status. An employee is entitled to a night pay differential...

  11. A repellent net as a new technology to protect cabbage crops.

    Science.gov (United States)

    Martin, T; Palix, R; Kamal, A; Delétré, E; Bonafos, R; Simon, S; Ngouajio, M

    2013-08-01

    Floating row covers or insect-proof nets with fine mesh are effective at protecting vegetable crops against aphids but negatively impact plant health, especially under warm conditions. Furthermore, in control of cabbage insect pests, aphid parasitoids cannot enter the fine-mesh nets, leading to frequent aphid outbreaks. To surmount these difficulties, a 40-mesh-size repellent net treated with alphacypermethrin was studied in laboratory and field tests. Results showed both irritant and repellent effects of the alphacypermethrin-treated net on Myzus persicae (Sulzer) (Hemiptera: Aphididae) and its parasitoid Aphidius colemani (Haliday) (Hymenoptera: Braconidae). Under field conditions, there were no pests on cabbage protected with the repellent net. The repellent net allowed combining a visual and repellent barrier against aphids. Because of this additive effect, repellent nets allowed covering cabbage permanently with adequate protection against all pests.

  12. Neurophysiological and behavioral responses of gypsy moth larvae to insect repellents: DEET, IR3535, and picaridin.

    Directory of Open Access Journals (Sweden)

    Jillian L Sanford

    Full Text Available The interactions between insect repellents and the olfactory system have been widely studied, however relatively little is known about the effects of repellents on the gustatory system of insects. In this study, we show that the gustatory receptor neuron (GRN located in the medial styloconic sensilla on the maxillary palps of gypsy moth larvae, and known to be sensitive to feeding deterrents, also responds to the insect repellents DEET, IR3535, and picaridin. These repellents did not elicit responses in the lateral styloconic sensilla. Moreover, behavioral studies demonstrated that each repellent deterred feeding. This is the first study to show perception of insect repellents by the gustatory system of a lepidopteran larva and suggests that detection of a range of bitter or aversive compounds may be a broadly conserved feature among insects.

  13. Mosquito repellent activity of essential oils of aromatic plants growing in Argentina.

    Science.gov (United States)

    Gillij, Y G; Gleiser, R M; Zygadlo, J A

    2008-05-01

    Mosquitoes are important vectors of diseases and nuisance pests. Repellents minimize contact with mosquitoes. Repellents based on essential oils (EO) are being developed as an alternative to DEET (N,N-diethyl-m-methylbenzamide), an effective compound that has disadvantages including toxic reactions, and damage to plastic and synthetic fabric. This work evaluated the repellency against Aedes aegypti of EO from aromatic plants that grow in Argentina: Acantholippia seriphioides, Achyrocline satureioides, Aloysia citriodora, Anemia tomentosa, Baccharis spartioides, Chenopodium ambrosioides, Eucalyptus saligna, Hyptis mutabilis, Minthostachys mollis, Rosmarinus officinalis, Tagetes minuta and Tagetes pusilla. Most EO were effective. Variations depending on geographic origin of the plant were detected. At a 90% EO concentration, A. satureoides and T. pusilla were the least repellent. At concentrations of 12.5% B. spartioides, R. officinalis and A. citriodora showed the longest repellency times. Comparisons of the principal components of each EO suggest that limonene and camphor were the main components responsible for the repellent effects.

  14. Repellence of essential oils of aromatic plants growing in Argentina against Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Gleiser, Raquel M; Bonino, Maria A; Zygadlo, Julio A

    2011-01-01

    Mosquitoes are vectors of pathogens to humans and domestic animals and may also have economical impacts. One approach to prevent mosquito-borne diseases is bite deterrence through the application of repellents. Currently, there is an interest to search for alternative bioactive products to the synthetic active ingredients most widely used in insect repellents. Repellence against Aedes aegypti of essential oils extracted from Acantholippia salsoloides, Aloysia catamarcensis, Aloysia polystachya, Lippia integrifolia, Lippia junelliana (Verbenaceae), Baccharis salicifolia, Euphatorium buniifolium, and Tagetes filifolia (Asteraceae) were assessed. Tests were conducted by alternatively exposing untreated and treated forehand to the mosquitoes and counting probing attempts. All essential oils tested were significantly repellent against A. aegypti when compared to untreated controls; L. junelliana was the most repellent and T. filifolia was the least based on the response of the mosquitoes to different concentrations of the essential oils (EO). Repellence may be attributed to the respective main components of each EO.

  15. Review of Virginia Woolf's Night and Day

    Directory of Open Access Journals (Sweden)

    Baker M Bani-Khair

    2017-01-01

    Full Text Available In this Review article, we have looked at different aspects that make Virginia Woolf's Night and Day one of the most interesting to read and analyze. We particularly focus on the familial and social patterns that distinguish this novel from other ones written by the same author. We also placed a good emphasis on the strength points the novel shows by looking at various elements such as themes of love relationships, modern treatment of plot and content, and more importantly on characterizations. The article revealed that Woolf's Night and Day is rich in terms of its modern and unconventional approach towards characters, plot, style, and thematic content which all make it a successful novel. Keywords: social stability, Virginia Woolf, Night and Day, techniques, styles, modernism, relationships, success, Marriage

  16. Water repellency in hydrophobic nanocapsules--molecular view on dewetting.

    Science.gov (United States)

    Müller, Achim; Garai, Somenath; Schäffer, Christian; Merca, Alice; Bögge, Hartmut; Al-Karawi, Ahmed Jasim M; Prasad, Thazhe Kootteri

    2014-05-26

    The hydrophobic effect plays a major role in a variety of important phenomena in chemistry, materials science and biology, for instance in protein folding and protein-ligand interactions. Studies--performed within cavities of the unique metal oxide based porous capsules of the type {(pentagon)12(linker)30}≡{(W)W5}12{Mo2(ligand)}30 with different acetate/water ligand ratios--have provided unprecedented results revealing segregation/repellency of the encapsulated "water" from the internal hydrophobic ligand walls of the capsules, while the disordered water molecules, interacting strongly with each other via hydrogen bonding, form in all investigated cases the same type of spherical shell. The present results can be (formally) compared--but only regarding the repellency effect--with the amazing "action" of the (super)hydrophobic Lotus (Nelumbo) leaves, which are self-cleaning based on water repellency resulting in the formation of water droplets picking up dirt. The present results were obtained by constructing deliberately suitable hydrophobic interiors within the mentioned capsules.

  17. Soil water repellency in long term drought and warming experiments

    Science.gov (United States)

    Urbanek, Emilia; Emmett, Bridget; Tietema, Albert; Robinson, David

    2017-04-01

    Increased global temperatures, altered rainfall patterns and frequently occurring extreme climatic events are already observed globally as a result of the climatic changes and further increases are predicted by the climatic models. Extreme weather events such as prolonged dry spells and heat waves can significantly affect soil ecosystem functions mainly due to decrease in soil moisture. Several studies suggested an increase in soil water repellency severity and spread as a consequence of the warming and drought, however, such understanding is based on the laboratory experimentations with soil treated as a 'black box'. In this study we tested the hypothesis of increased severity of soil water repellency subjected to drought and warming under field conditions. Occurrence and severity of soil water repellency was tested in soils subjected to a long-term (10 years) climatic simulation at two upland heathland sites in Oldebroek (Netherlands) and in Clocaenog (UK)[1]. Soil plots with similar vegetation were subjected to repeated drought and warming, compared with the control plots. Drought effect was created by a rainfall exclusion using an automatic self-retracting waterproof curtains while the warming effect was made by using a self-retracting curtains reflecting infrared radiation overnight. The results available to date provide a strong indication that climatic conditions do affect the development of SWR.

  18. Bacteria repelling on highly-ordered alumina-nanopore structures

    Science.gov (United States)

    Kim, Sunghan; Zhou, Yan; Cirillo, Jeffrey D.; Polycarpou, Andreas A.; Liang, Hong

    2015-04-01

    Bacteria introduce diseases and infections to humans by their adherence to biomaterials, such as implants and surgical tools. Cell desorption is an effective step to reduce such damage. Here, we report mechanisms of bacteria desorption. An alumina nanopore structure (ANS) with pore size of 35 nm, 55 nm, 70 nm, and 80 nm was used as substrate to grow Escherichia coli (E. coli) cells. A bacteria repelling experimental method was developed to quantitatively evaluate the area percentage of adherent bacterial cells that represent the nature of cell adhesion as well as desorption. Results showed that there were two crucial parameters: contact angle and contact area that affect the adhesion/desorption. The cells were found to be more easily repelled when the contact angle increased. The area percentage of adherent bacterial cells decreased with the decrease in the contact area of a cell on ANS. This means that cell accessibility on ANS depends on the contact area. This research reveals the effectiveness of the nanopored structures in repelling cells.

  19. Does Zika virus infection affect mosquito response to repellents?

    Science.gov (United States)

    Leal, Walter S.; Barbosa, Rosângela M. R.; Zeng, Fangfang; Faierstein, Gabriel B.; Tan, Kaiming; Paiva, Marcelo H. S.; Guedes, Duschinka R. D.; Crespo, Mônica M.; Ayres, Constância F. J.

    2017-01-01

    The World Health Organization (WHO) recommends that people travelling to or living in areas with Zika virus (ZIKV) outbreaks or epidemics adopt prophylactic measures to reduce or eliminate mosquito bites, including the use of insect repellents. It is, however, unknown whether repellents are effective against ZIKV-infected mosquitoes, in part because of the ethical concerns related to exposing a human subject’s arm to infected mosquitoes in the standard arm-in-cage assay. We used a previously developed, human subject-free behavioural assay, which mimics a human subject to evaluate the top two recommended insect repellents. Our measurements showed that DEET provided significantly higher protection than picaridin provided against noninfected, host-seeking females of the southern house mosquito, Culex quinquefasciatus, and the yellow fever mosquito, Aedes aegypti. When tested at lower doses, we observed a significant reduction in DEET-elicited protection against ZIKV-infected yellow fever mosquitoes from old and recent laboratory colonies. The reduction in protection is more likely associated with aging than the virus infection and could be compensated by applying a 5x higher dose of DEET. A substantial protection against ZIKV-infected and old noninfected mosquitoes was achieved with 5% DEET, which corresponds approximately to a 30% dose in the conventional arm-in-cage assays. PMID:28205633

  20. The Night-Death binomial as a poetic ploy - a cross-cultural look from the graveyard poets to expressionism

    Directory of Open Access Journals (Sweden)

    Lioba Simon-Schuhmacher

    2015-11-01

    Full Text Available The essay describes the use of the Night-Death binomial and tracks its evolution from the eighteenth century to Expressionism across Great Britain, Germany, Spain, and Austria, at the hand of poems such as Edward Young’s Night Thoughts (1745, Novalis’s Hymnen an die Nacht, (1800, José Blanco White’s sonnet “Night and Death” (1828, and Georg Trakl’s “Verwandlung des Bösen” (1914. Romanticism brought along a preference for the nocturnal: night, moonlight, shades and shadows, mist and mystery, somber mood, morbidity, and death, as opposed to the Enlightenment’s predilection for day, light, clarity, and life. The essay analyses how poets from different national contexts and ages employ images and symbols of the night to create an association with death. It furthermore shows how, with varying attitudes and results, they manage to convert this binomial into a poetic ploy.

  1. Snap-Back Repellers and Chaos in Time-delayed Chua's Circuit

    Institute of Scientific and Technical Information of China (English)

    Yu Chang

    2005-01-01

    The chaotic behavior of one-dimensional, 2-segment and 3-segment piecewise-linear maps is examined by using the concept of snap-back repellers introduced by Marotto and the parameters conditions of existence for snap-back repeller are obtained. Simulation results are presented to show the snap-back repeller,some periodic points and attracting interval cycles with chaotic intervals.

  2. From superhydrophobicity and water repellency to superhydrophilicity: smart polymer-functionalized surfaces.

    Science.gov (United States)

    Stratakis, Emmanuel; Mateescu, Anca; Barberoglou, Marios; Vamvakaki, Maria; Fotakis, Costas; Anastasiadis, Spiros H

    2010-06-21

    pH-responsive surfaces, reversibly switching between superhydrophilicity and superhydrophobicity/water repellency, are developed by "grafting from" a pH-sensitive polymer onto a hierarchically micro/nano-structured substrate. We quantify the water repellency by investigating the restitution coefficient of water droplets bouncing off the surfaces. The water repellent state requires appropriate hydrophobicity of the functionalizing polymer as well as very low values of contact angle hysteresis.

  3. Field Evaluation of Four Spatial Repellent Devices Against Arkansas Rice-Land Mosquitoes

    Science.gov (United States)

    2014-03-01

    FIELD EVALUATION OF FOUR SPATIAL REPELLENT DEVICES AGAINST ARKANSAS RICE-LAND MOSQUITOES DAVID A. DAME,1 MAX V. MEISCH,2 CAROLYN N. LEWIS,2 DANIEL L... mosquitoes to locate a host. There are many commercially available spatial repellent products currently on the market. These products include...a large rice growing area where late-spring and summer agricultural irriga- tion generates dense mosquito populations. Spatial repellent devices

  4. Multitudes attend the Night of Science

    CERN Multimedia

    2006-01-01

    The Night of Science, which took place in the Parc de la Perle du Lac in Geneva last weekend, was a great success, with 30 000 visitors attending according to the organisers. Many curious people flocked to the stands and animations until late on Saturday night and all afternoon on Sunday. The CERN stand (photo) received a great amount of interest from participants. Both kids and adults discovered the activities of the Laboratory and the data-processing revolution initiated by CERN, from the Web to the Computing Grid. Hats off to the CERN collaborators in the Communication Group and IT Department who made this event a success.

  5. Cockpit Readiness For Night Vision Goggles

    Science.gov (United States)

    Scholl, Marija S.; Scholl, James W.

    1987-09-01

    The introduction of night vision goggles into the cockpit environment may produce incompatibility with existing cockpit optoelectronic instrumentation. The methodology used to identify the origin of the spurious signal is demonstrated with the example of an electronic display. The amount of radiation emitted by a gray body in the wavelength region of goggle sensitivity is calculated. A simple procedure for preflight testing of cockpit instrumentation using a commercially available infrared camera is recommended. Other recommendations include the specification of cockpit instrumentation for compatibility with night vision devices.

  6. AMOLED image source for use in integrated panoramic night vision goggle (IPNVG)

    Science.gov (United States)

    Ross, Jeff A.; Parisi, Vince

    2004-09-01

    The objective of this paper is to present an overview of the active matrix organic light emitting diode (OLED) microdisplay used in the integrated panoramic night vision goggle (IPNVG). These devices will be used to insert independent and overlaid video imagery into the IPNVG. Interface and operational details of the microdisplay relative to the IPNVG implementation in military aircraft will be discussed.

  7. Dazzling Displays of Fireworks and Lanterns Shine the Night of Paris

    Institute of Scientific and Technical Information of China (English)

    LiShegxian

    2004-01-01

    The night of July 2, 2004. The Palace of Versaille. Chinese-style red palace lanterns glittered amid trees and lotus lights with oriental charm floated in the lake. Distinguished guests from China and thousands of French celebrities and officials gathered to await the closing of China Cultural Year. When the clock struck twelve, vigorous music suddenly sounded

  8. Substrate-Independent, Transparent Oil-Repellent Coatings with Self-Healing and Persistent Easy-Sliding Oil Repellency.

    Science.gov (United States)

    Yu, Li; Chen, George Y; Xu, Haolan; Liu, Xiaokong

    2016-01-26

    Herein we report a simple and substrate-independent approach to fabricate transparent oil-repellent coatings, which involves alternate deposition of poly(diallyldimethylammonium) (PDDA) and poly(styrenesulfonate) (PSS) onto substrates, followed by incubation of the coated objects into perfluorooctanoate (PFO) aqueous solutions for 2 min. Various low-surface-tension liquids can easily slide down the coating surfaces on flat substrates at a sliding angle lower than 12° for 10 μL droplets. The coatings are applicable to different substrates including Si, glass, plastic, steel, and wood, and those with complex shapes and large surface areas. They are also applicable to rough substrates with roughness at both micro/nanoscale and macroscopic scales to realize the easy-sliding oil repellency. Incubation of the PDDA/PSS polyelectrolyte multilayers (PEMs) into PFO solutions induces an effective but nondestructive substitution of PFO anions for PSS in the PEMs, which results in a composite coating with PFO anions homogeneously interspersed in both the coating surface and the bulk. Thanks to the as-described "repeating-layer" composition/structure of the coatings, their easy-sliding oil repellency can be self-healed after surface decomposition or well maintained after physical damages, due to the replenishing surface. Therefore, the advantageous characteristics of the as-developed oil-repellent coatings and the simplicity of the preparation protocol make the coatings highly practical for real-world applications. It is believed that the coatings can perform as antismudge coatings that shield against oil-borne contaminants, chemical-shield coatings that protect coated plastics from dissolution by organic solvents, and nonstick coatings (of oil tankers or pipelines) that enable loss-free oil transportation.

  9. Shift Work, Chronotype, and Melatonin Patterns among Female Hospital Employees on Day and Night Shifts.

    Science.gov (United States)

    Leung, Michael; Tranmer, Joan; Hung, Eleanor; Korsiak, Jill; Day, Andrew G; Aronson, Kristan J

    2016-05-01

    Shift work-related carcinogenesis is hypothesized to be mediated by melatonin; however, few studies have considered the potential effect modification of this underlying pathway by chronotype or specific aspects of shift work such as the number of consecutive nights in a rotation. In this study, we examined melatonin patterns in relation to shift status, stratified by chronotype and number of consecutive night shifts, and cumulative lifetime exposure to shift work. Melatonin patterns of 261 female personnel (147 fixed-day and 114 on rotations, including nights) at Kingston General Hospital were analyzed using cosinor analysis. Urine samples were collected from all voids over a 48-hour specimen collection period for measurement of 6-sulfatoxymelatonin concentrations using the Buhlmann ELISA Kit. Chronotypes were assessed using mid-sleep time (MSF) derived from the Munich Chronotype Questionnaire (MCTQ). Sociodemographic, health, and occupational information were collected by questionnaire. Rotational shift nurses working nights had a lower mesor and an earlier time of peak melatonin production compared to day-only workers. More pronounced differences in mesor and acrophase were seen among later chronotypes, and shift workers working ≥3 consecutive nights. Among nurses, cumulative shift work was associated with a reduction in mesor. These results suggest that evening-types and/or shift workers working ≥3 consecutive nights are more susceptible to adverse light-at-night effects, whereas long-term shift work may also chronically reduce melatonin levels. Cumulative and current exposure to shift work, including nights, affects level and timing of melatonin production, which may be related to carcinogenesis and cancer risk. Cancer Epidemiol Biomarkers Prev; 25(5); 830-8. ©2016 AACR. ©2016 American Association for Cancer Research.

  10. The efficacy of repellents against Aedes, Anopheles, Culex and Ixodes spp. - a literature review.

    Science.gov (United States)

    Lupi, Eleonora; Hatz, Christoph; Schlagenhauf, Patricia

    2013-01-01

    Travellers are confronted with a variety of vector-borne threats. Is one type of repellent effective against all biting vectors? The aim of this review is to examine the literature, up to December 31st, 2012, regarding repellent efficacy. We searched PubMed for relevant papers. Repellents of interest were DEET, Icaridin as well as other piperidine-derived products (SS220), Insect Repellent (IR) 3535 (ethyl-butylacetyl-amino-propionat, EBAAP) and plant-derived products, including Citriodora (para-menthane-3,8-diol). As vectors, we considered the mosquito species Anopheles, Aedes and Culex as well as the tick species Ixodes. We selected only studies evaluating the protective efficacy of repellents on human skin. We reviewed a total of 102 publications. Repellents were evaluated regarding complete protection time or as percentage efficacy [%] in a time interval. We found no standardized study for tick bite prevention. Regarding Aedes, DEET at concentration of 20% or more, showed the best efficacy providing up to 10 h protection. Citriodora repellency against this mosquito genus was lower compared to the other products. Also between subspecies a difference could be observed: Ae. aegypti proved more difficult to repel than Ae. Albopictus. Fewer studies have been conducted on mosquito species Anopheles and Culex. The repellency profile against Anopheles species was similar for the four principal repellents of interest, providing on average 4-10 h of protection. Culex mosquitoes are easier to repel and all four repellents provided good protection. Few studies have been conducted on the tick species Ixodes. According to our results, the longest protection against Ixodes scapularis was provided by repellents containing IR3535, while DEET and commercial products containing Icaridin or PMD showed a better response than IR3535 against Ixodes ricinus. Many plant-based repellents provide only short duration protection. Adding vanillin 5% to plant-based repellents and to DEET

  11. Evaluation of biological and chemical insect repellents and their potential adverse effects.

    Science.gov (United States)

    Semmler, Margit; Abdel-Ghaffar, Fathy; Schmidt, Jürgen; Mehlhorn, Heinz

    2014-01-01

    Plant extracts, particularly plant oils, had been used and were still in use as repellents against mosquitoes. Some of them (e.g., lavender, geraniol, and citriodiol) have been notified by the European Commission as active substances to be used in repellents, which are categorized as biocides in product type 19. In the literature, it is known that these substances must be added to repellent products in high concentrations (e.g., 20% and more) in order to reach repellent efficacy. Therefore, the question arose whether they also have repellent effects if they were added as fragrances at low concentrations of 0.25 or 1% to registered active substances in order to obtain a better scent of this product. In the present study, the repellent effects of 0.25 and 1% additions of 15 plant extracts (citronellol, cinerol, citral, menthol, linalyl acetate, Eucalyptus citriodora, Eucalyptus globulus, Cymbopogon nardus, lilac, sandalwood, Vitex agnus castus, rosewood, lavender, geraniol, and paramenthan diol) when exposed on skin to hungry Aedes aegypti mosquitoes. These experiments showed that there was no repellent effect in any of these compounds even when the test was done already 10 min after distributing any of the compounds onto the hands of volunteers. These experiments have proven that these 15 compounds do not produce repellent effects as long as they are used in low concentrations of 0.25 or 1% as fragrances to ameliorate the odor of a notified repellent that is brought onto the skin.

  12. Repellency of Plant Extracts against the Legume Flower Thrips Megalurothrips sjostedti (Thysanoptera: Thripidae

    Directory of Open Access Journals (Sweden)

    Andnet Abtew

    2015-06-01

    Full Text Available Megalurothrips sjostedti Trybom is an important pest of cowpea (Vigna unguiculata L. in Africa. To propose an alternative to chemical control, the repellency of 24 plant extracts was evaluated against adult female thrips of M. sjostedti in the laboratory. Plant extracts in ethanol were separately applied on a filter paper disk in a still air visual cue olfactometer. The results showed highly significant differences in repellency among extract type, concentration and their interactions. We classified the level of repellency into four categories as strong, good, moderate and weak or non- repellent based on hierarchical ascendant classification. We identified Piper nigrum, Cinnamomum zeylanicum, Cinnamomum cassia as strong repellents. Five extracts were classified as good, eight as moderate and the remaining eight extracts were weak or non-repellent. Repellency of the extracts increased with the concentration suggesting that the behavioral response of M. sjostedti was dose-dependent. Mono- and sesquiterpene hydrocarbon compounds from seven highly repellent extracts were identified by gas chromatography-mass spectrometry (GC/MS. The use of repellent extracts could be useful in developing integrated pest management strategies for thrips on legume crops. In this regard, the specific modes of action of the identified compounds need to be investigated to incorporate them into the existing crop protection strategies.

  13. Moisture characteristics of water-repellent consolidants and their applicability to existing buildings

    Science.gov (United States)

    Iba, Chiemi; Fukui, Kazuma; Hokoi, Shuichi

    2016-07-01

    Water-repellent agents are considered an effective measure of preventing moisture damage in building materials. However, data on the moisture transfer characteristics of repellent materials are insufficient. This study focused on the transfer of liquid water in a porous building material and quantitatively evaluated the applicability of a water-repellent consolidant as a protection agent via water infiltration experiments and numerical analysis. The experimental results could be reproduced by treating the water-repellent consolidant as having two layers with different water conductivities.

  14. Analysis of Thursday Night NFL Winning Margins

    Science.gov (United States)

    Vaughan, Timothy S.

    2015-01-01

    This paper introduces a dataset and associated analysis of the scores of National Football League (NFL) games over the 2012, 2013, and first five weeks of the 2014 season. In the face of current media attention to "lopsided" scores in Thursday night games in the early part of the 2014 season, t-test results indicate no statistically…

  15. What's crucial in night vision goggle simulation ?

    NARCIS (Netherlands)

    Kooi, F.L.; Toet, A.

    2005-01-01

    Training is required to correctly interpret NVG imagery. Training night operations with simulated intensified imagery has great potential. Compared to direct viewing with the naked eye, intensified imagery is relatively easy to simulate and the cost of real NVG training is high (logistics, risk,

  16. Behavioral management of night eating disorders

    Directory of Open Access Journals (Sweden)

    Berner LA

    2013-03-01

    Full Text Available Laura A Berner,1 Kelly C Allison2 1Department of Psychology, Drexel University, 2Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA Abstract: Night eating syndrome (NES is a form of disordered eating associated with evening hyperphagia (overeating at night and nocturnal ingestions (waking at night to eat. As with other forms of disordered eating, cognitive and behavioral treatment modalities may be effective in reducing NES symptoms. This review presents evidence for a variety of behavioral treatment approaches, including behavioral therapy, phototherapy, behavioral weight loss treatment, and cognitive-behavioral therapy. A more detailed overview of cognitive-behavioral therapy for NES is provided. All of these studies have been case studies or included small samples, and all but one have been uncontrolled, but the outcomes of many of these approaches are promising. Larger randomized controlled trials are warranted to advance NES treatment literature. With the inclusion of NES in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5 as a “Feeding or Eating Disorder Not Elsewhere Classified,” more sophisticated, empirically-supported, behaviorally-based treatment approaches are much needed. Keywords: night eating syndrome, cognitive-behavioral treatment, phototherapy, behavioral weight loss, behavior therapy

  17. Family Literacy Night: A Celebration of Reading!

    Science.gov (United States)

    Campbell, Becky; Morton, Shirley; Rumschlag, Hella

    2011-01-01

    Family Literacy Night is an exciting way to engage students and their parents in meaningful literacy activities while building community spirit and strengthening the partnership between school and home. It is an opportunity for students to show their parents what they do in school; how they create in the computer lab, how they work in the art…

  18. Invite an Alien to Astronomy Night

    Science.gov (United States)

    Governor, Donna; Richwine, Pebble

    2007-01-01

    Dozens of inflatable aliens recently "descended" upon the authors' middle school to kick-off their first school-wide Astronomy night. With an estimated attendance of over 500, their eighth-grade students hosted over a dozen activity-rich sessions designed to entertain and educate students and their families about the wonders of the solar system…

  19. Helicopter Night Vision System Simulation Evaluation

    Science.gov (United States)

    1981-12-01

    mision safety. The enroute evaluation indicates a con- sistent preference for the 4HMD-PMD configuration. The copilot felt that the virtual HUD...pilot but never allowed Cho copilot to slow in a hover. In edsencer the night cranpore mision appears wo be a two pilot task with a t consant verbal

  20. Methods and Strategies: Math and Science Night

    Science.gov (United States)

    Sullivan, Joan; Hatton, Mary

    2011-01-01

    Family Math and Science Nights engage students and parents in active investigations tied to the curriculum in a fun, informal environment. Through this program, families actively explore math and science ideas, discover together through guided inquiry, and apply their discoveries to solve a problem at the end. All activities are hands-on, use…

  1. Science by night – it's magic!

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    The control rooms of the LHC and its experiments threw open their doors to 150 youngsters on European Researchers Night and the place was buzzing with excitement all evening!    It's just possible that a few scientists' vocations were born last Friday night, as the sixth European Researchers Night took place across Europe. CERN was taking part for the first time and invited young people aged from 12 to 19 into the control rooms of the LHC machine and five experiments. From 5.00 in the afternoon until 1.00 in the morning, 150 youngsters and physics teachers got the opportunity to sit with scientists at the controls of the accelerator and experiments. This meeting of minds went down very well for all concerned, the scientists being only too happy to wax lyrical about their passion. The youngsters were thrilled with their visit and amazed at being allowed so close to the controls of these mighty machines. The night-time setting added an extra touch of magic to the whole event. Some just could...

  2. Sirius brightest diamond in the night sky

    CERN Document Server

    Holberg, Jay B

    2007-01-01

    This book describes why Sirius has been regarded as an important fixture of the night sky since the beginnings of history. It also examines the part that Sirius has played in how we came to achieve our current scientific understanding of stars.

  3. Portable real-time color night vision

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2008-01-01

    We developed a simple and fast lookup-table based method to derive and apply natural daylight colors to multi-band night-time images. The method deploys an optimal color transformation derived from a set of samples taken from a daytime color reference image. The colors in the resulting colorized mul

  4. What's crucial in night vision goggle simulation ?

    NARCIS (Netherlands)

    Kooi, F.L.; Toet, A.

    2005-01-01

    Training is required to correctly interpret NVG imagery. Training night operations with simulated intensified imagery has great potential. Compared to direct viewing with the naked eye, intensified imagery is relatively easy to simulate and the cost of real NVG training is high (logistics, risk, civ

  5. Portable real-time color night vision

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2008-01-01

    We developed a simple and fast lookup-table based method to derive and apply natural daylight colors to multi-band night-time images. The method deploys an optimal color transformation derived from a set of samples taken from a daytime color reference image. The colors in the resulting colorized mul

  6. Portable real-time color night vision

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2008-01-01

    We developed a simple and fast lookup-table based method to derive and apply natural daylight colors to multi-band night-time images. The method deploys an optimal color transformation derived from a set of samples taken from a daytime color reference image. The colors in the resulting colorized

  7. The Night Of Hennessy Paradis Extra Cognac

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正>The world-known Hennessy Paradis Extra Cognaclaunched its"dazzling night"on the evening of May 22 tolet guests enjoy to their hearts’content the fine wine andthe charming glamour of the diamond evening dress. A liquid,dating back to the 18th century,was called

  8. Why Is the Sky Dark at Night?

    Science.gov (United States)

    Stinner, Arthur

    2014-01-01

    The puzzle as to just why the sky is dark at night, given that there are so many stars, has been around at least since Newton. This article summarizes six cosmological models that have been used to attempt to give an account of this puzzle including the Copernican universe, the Newton-Halley universe, the nineteenth century "one galaxy"…

  9. Field evaluation of deet, Repel Care, and three plant based essential oil repellents against mosquitoes, black flies (Diptera: Simuliidae) and land leeches (Arhynchobdellida: Haemadipsidae) in Thailand.

    Science.gov (United States)

    Tawatsin, Apiwat; Thavara, Usavadee; Chansang, Uruyakorn; Chavalittumrong, Pranee; Boonruad, Thidarat; Wongsinkongman, Prapai; Bansidhi, Jaree; Mulla, Mir S

    2006-06-01

    Diethyl methyl benzamide, or deet, a commercial plant-based repellent (Repel Care), and essential ils from 3 species of plants (finger root rhizomes, guava leaves, and turmeric rhizomes), steam distillated and formulated as insect repellents, were evaluated in the field on human volunteers against hematophagous mosquitoes, black flies, and land leeches in Thailand. Field trials were conducted against wild mosquitoes in Bang Bua Thong District, Nonthaburi Province, and in the Thap Lan National Park Headquarters, Nadee District, Pranchinburi Province; anthroophilic black flies (Diptera: Simuliidae) at the Forestry Fire Control Station in Doi Inthanon National Park, Chomthong district, Chiang Mai Province; and land leeches (Arhynchobdellida: Haemadipsidae) in the Khao Yai National Park, Pak Chong District, Nakhon Ratchasima Province. The 3 experimental plant-based essential oil formulations as well as Repel Care and deet provided complete protection from mosquito landing and biting for up to 9 h (duration of the experiment). Similar results were obtained with the 5 products against black flies, providing 100% protection for 9 h but 96-82% protection after 10 and 11 h posttreatment. The 5 repellent products also provided 100% protection against land leeches for at least 8 h. Thi is the 1st report of repellency of plant-based repellents against black flies and land leeches in Thailand. The identification and availability of inexpensive sources of plant-based oils, i.e., finger root rhizomes, guava leaves, and turmeric rhizomes providing long-lasting repellency against blood-sucking organisms are promising leads into commercial production of relatively safe and effective repellents.

  10. New weather depiction technology for night vision goggle (NVG) training

    Science.gov (United States)

    Theleman, Scott; Hegarty, Jennifer; Vollmerhausen, Richard; Scott, Courtney; Schroeder, John; Colby, Frank P.; Napier, S.

    2006-08-01

    US Navy and Marine Corps pilots receive Night Vision Goggle (NVG) training as part of their overall training to maintain the superiority of our forces. This training must incorporate realistic targets; backgrounds; and representative atmospheric and weather effects they may encounter under operational conditions. An approach for pilot NVG training is to use the Night Imaging and Threat Evaluation Laboratory (NITE Lab) concept. The NITE Labs utilize a 10' by 10' static terrain model equipped with both natural and cultural lighting that are used to demonstrate various illumination conditions, and visual phenomena which might be experienced when utilizing night vision goggles. With this technology, the military can safely, systematically, and reliably expose pilots to the large number of potentially dangerous environmental conditions that will be experienced in their NVG training flights. This paper describes work that is being performed for NAVAIR to add realistic atmospheric and weather effects to the NVG NITE Lab training facility using the NVG-WDT (Weather Dipiction Technology) system. NVG-WDT consist of a high end multiprocessor server with weather simulation software, and several fixed and goggle mounted Heads Up Displays (HUDs). Atmospheric and weather effects are simulated using state-of-the-art computer codes such as the NCAR/Penn State Mesoscale Model (MM5); and the US Air Force Research Laboratory MODTRAN radiative transport model. Imagery for a variety of natural and man-made obscurations (e.g. rain, clouds, snow, dust, smoke, chemical releases) is being calculated and injected into the scene observed through the NVG via the fixed and goggle mounted HUDs.

  11. Anthropogenic disruption of the night sky darkness in urban and rural areas.

    Science.gov (United States)

    Bará, Salvador

    2016-10-01

    The growing emissions of artificial light to the atmosphere are producing, among other effects, a significant increase of the night sky brightness (NSB) above its expected natural values. A permanent sensor network has been deployed in Galicia (northwest of Iberian peninsula) to monitor the anthropogenic disruption of the night sky darkness in a countrywide area. The network is composed of 14 detectors integrated in automated weather stations of MeteoGalicia, the Galician public meteorological agency. Zenithal NSB readings are taken every minute and the results are openly available in real time for researchers, interested stakeholders and the public at large through a dedicated website. The measurements allow one to assess the extent of the loss of the natural night in urban, periurban, transition and dark rural sites, as well as its daily and monthly time courses. Two metrics are introduced here to characterize the disruption of the night darkness across the year: the significant magnitude (m1/3) and the moonlight modulation factor (γ). The significant magnitude shows that in clear and moonless nights the zenithal night sky in the analysed urban settings is typically 14-23 times brighter than expected from a nominal natural dark sky. This factor lies in the range 7-8 in periurban sites, 1.6-2.5 in transition regions and 0.8-1.6 in rural and mountain dark sky places. The presence of clouds in urban areas strongly enhances the amount of scattered light, easily reaching amplification factors in excess of 25, in comparison with the light scattered in the same places under clear sky conditions. The periodic NSB modulation due to the Moon, still clearly visible in transition and rural places, is barely notable at periurban locations and is practically lost at urban sites.

  12. Anthropogenic disruption of the night sky darkness in urban and rural areas

    Science.gov (United States)

    Bará, Salvador

    2016-10-01

    The growing emissions of artificial light to the atmosphere are producing, among other effects, a significant increase of the night sky brightness (NSB) above its expected natural values. A permanent sensor network has been deployed in Galicia (northwest of Iberian peninsula) to monitor the anthropogenic disruption of the night sky darkness in a countrywide area. The network is composed of 14 detectors integrated in automated weather stations of MeteoGalicia, the Galician public meteorological agency. Zenithal NSB readings are taken every minute and the results are openly available in real time for researchers, interested stakeholders and the public at large through a dedicated website. The measurements allow one to assess the extent of the loss of the natural night in urban, periurban, transition and dark rural sites, as well as its daily and monthly time courses. Two metrics are introduced here to characterize the disruption of the night darkness across the year: the significant magnitude (m1/3) and the moonlight modulation factor (γ). The significant magnitude shows that in clear and moonless nights the zenithal night sky in the analysed urban settings is typically 14-23 times brighter than expected from a nominal natural dark sky. This factor lies in the range 7-8 in periurban sites, 1.6-2.5 in transition regions and 0.8-1.6 in rural and mountain dark sky places. The presence of clouds in urban areas strongly enhances the amount of scattered light, easily reaching amplification factors in excess of 25, in comparison with the light scattered in the same places under clear sky conditions. The periodic NSB modulation due to the Moon, still clearly visible in transition and rural places, is barely notable at periurban locations and is practically lost at urban sites.

  13. Evolution of the ATLAS Nightly Build System

    Science.gov (United States)

    Undrus, A.

    2012-12-01

    The ATLAS Nightly Build System is a major component in the ATLAS collaborative software organization, validation, and code approval scheme. For over 10 years of development it has evolved into a factory for automatic release production and grid distribution. The 50 multi-platform branches of ATLAS releases provide vast opportunities for testing new packages, verification of patches to existing software, and migration to new platforms and compilers for ATLAS code that currently contains 2200 packages with 4 million C++ and 1.4 million python scripting lines written by about 1000 developers. Recent development was focused on the integration of ATLAS Nightly Build and Installation systems. The nightly releases are distributed and validated and some are transformed into stable releases used for data processing worldwide. The ATLAS Nightly System is managed by the NICOS control tool on a computing farm with 50 powerful multiprocessor nodes. NICOS provides the fully automated framework for the release builds, testing, and creation of distribution kits. The ATN testing framework of the Nightly System runs unit and integration tests in parallel suites, fully utilizing the resources of multi-core machines, and provides the first results even before compilations complete. The NICOS error detection system is based on several techniques and classifies the compilation and test errors according to their severity. It is periodically tuned to place greater emphasis on certain software defects by highlighting the problems on NICOS web pages and sending automatic e-mail notifications to responsible developers. These and other recent developments will be presented and future plans will be described.

  14. Substitution of PFAS chemistry in outdoor apparel and the impact on repellency performance.

    Science.gov (United States)

    Hill, Philippa J; Taylor, Mark; Goswami, Parikshit; Blackburn, Richard S

    2017-08-01

    Intensifying legislation and increased research on the toxicological and persistent nature of per- and polyfluoroalkyl substances (PFASs) have recently influenced the direction of liquid repellent chemistry use; environmental, social, and sustainability responsibilities are at the crux. Without PFAS chemistry, it is challenging to meet current textile industry liquid repellency requirements, which is a highly desirable property, particularly in outdoor apparel where the technology helps to provide the wearer with essential protection from adverse environmental conditions. Herein, complexities between required functionality, legislation and sustainability within outdoor apparel are discussed, and fundamental technical performance of commercially available long-chain (C8) PFASs, shorter-chain (C6) PFASs, and non-fluorinated repellent chemistries finishes are evaluated comparatively. Non-fluorinated finishes provided no oil repellency, and were clearly inferior in this property to PFAS-finished fabrics that demonstrated good oil-resistance. However, water repellency ratings were similar across the range of all finished fabrics tested, all demonstrating a high level of resistance to wetting, and several non-fluorinated repellent fabrics provide similar water repellency to long-chain (C8) PFAS or shorter-chain (C6) PFAS finished fabrics. The primary repellency function required in outdoor apparel is water repellency, and we would propose that the use of PFAS chemistry for such garments is over-engineering, providing oil repellency that is in excess of user requirements. Accordingly, significant environmental and toxicological benefits could be achieved by switching outdoor apparel to non-fluorinated finishes without a significant reduction in garment water-repellency performance. These conclusions are being supported by further research into the effect of laundering, abrasion and ageing of these fabrics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Night vision goggles, human factors aspects--a questionnaire survey of helicopter aircrew.

    Science.gov (United States)

    Manton, A G

    2000-02-01

    Night vision goggles have become an essential component of military aviation. They provide superior visual capability over unaided night vision, but there are several inherent limitations associated with human factors and systems limitations. This study used a questionnaire survey of Army helicopter aircrew to investigate the incidence of human factors problems which continued after NVG use, with particular reference to visual problems and neck discomfort. It also looked at hardware interaction problems, such as cockpit lighting, and other aspects of NVG use, such as training and aircrew concerns. The issues are described and analysed, and areas of concern, which may have bearings on operational effectiveness and/or safety, have been highlighted.

  16. Vegetation-induced soil water repellency as a strategy in arid ecosystems. A geochemical approach in Banksia woodlands (SW Australia)

    Science.gov (United States)

    Muñoz-Rojas, Miriam; Jiménez-Morillo, Nicasio T.; González-Pérez, Jose Antonio; Zavala, Lorena M.; Stevens, Jason; Jordan, Antonio

    2016-04-01

    research aims to study SWR and its impact on water economy in relation with soil functioning and plant strategies for water uptake in pristine BW. Results are expected to shed light on the origin and implications of SWR in the area and provide useful information for improving ongoing restoration plans. Materials and methods The study was conducted in natural BW of WA. Soil samples were collected at different soil depths (0-1, 1-10, 20-30 and 40-50 cm). Rationale for sampling depths was based on the different severities of SWR at each layer under field conditions. Soil water repellency was assessed under laboratory conditions in oven-dry samples (48 h, 105 °C) and the chemical organic assemblage of bulked soil subsamples from each layer was analysed by direct analytical pyrolysis (Py-GC/MS). Results and discussion Soil water repellency distributed discontinuously through the soil profile. The first thin layer (0-1 cm) composed of coarse sand and litter, located immediately above Banksia root clusters, showed wettable conditions. In contrast, the relatively well aggregated soil layer where the Banksia cluster root system is located (1-10 cm) was severely water-repellent. The 20-30 and 40-50 cm deep layers rendered wettable or subcritically water-repellent. After Py-GC/MS analysis, major compounds were identified and grouped according to their probable biogenic origin (lignin, polysaccharides, peptides, etc.). Among other soil organic compounds, well resolved bimodal alkane/akene (C8-C31, maxima at C13 and C26) and fatty acids series (short-chained, C5-C9, and long-chained even-numbered C12-C18) were associated to the root cluster soil layer (1-10 cm). Also, a relatively high contribution of fire-derived polycyclic aromatic hydrocarbons (PAHs) was observed (7%), which is consistent with frequent fires occurring in BW. These results point to possible indirect links between organic substances released by roots and soil wettability involving soil microorganisms. Further

  17. Evaluation of DEET and eight essential oils for repellency against nymphs of the lone star tick, Amblyomma americanum (Acari: Ixodidae)

    Science.gov (United States)

    Eight commercially available essential oils (oregano, clove, thyme, vetiver, sandalwood, cinnamon, cedarwood, and peppermint) were evaluated for repellency against host-seeking nymphs of the lone star tick, Amblyomma americanum. Concentration- repellency response was established using the vertical ...

  18. The first world atlas of the artificial night sky brightness

    CERN Document Server

    Cinzano, P; Elvidge, C D

    2001-01-01

    We present the first World Atlas of the zenith artificial night sky brightness at sea level. Based on radiance calibrated high resolution DMSP satellite data and on accurate modelling of light propagation in the atmosphere, it provides a nearly global picture of how mankind is proceeding to envelope itself in a luminous fog. Comparing the Atlas with the U.S. Department of Energy (DOE) population density database we determined the fraction of population who are living under a sky of given brightness. About two thirds of the World population and 99% of the population in US (excluding Alaska and Hawaii) and EU live in areas where the night sky is above the threshold set for polluted status. Assuming average eye functionality, about one fifth of the World population, more than two thirds of the US population and more than one half of the EU population have already lost naked eye visibility of the Milky Way. Finally, about one tenth of the World population, more than 40% of the US population and one sixth of the E...

  19. NV-CMOS HD camera for day/night imaging

    Science.gov (United States)

    Vogelsong, T.; Tower, J.; Sudol, Thomas; Senko, T.; Chodelka, D.

    2014-06-01

    SRI International (SRI) has developed a new multi-purpose day/night video camera with low-light imaging performance comparable to an image intensifier, while offering the size, weight, ruggedness, and cost advantages enabled by the use of SRI's NV-CMOS HD digital image sensor chip. The digital video output is ideal for image enhancement, sharing with others through networking, video capture for data analysis, or fusion with thermal cameras. The camera provides Camera Link output with HD/WUXGA resolution of 1920 x 1200 pixels operating at 60 Hz. Windowing to smaller sizes enables operation at higher frame rates. High sensitivity is achieved through use of backside illumination, providing high Quantum Efficiency (QE) across the visible and near infrared (NIR) bands (peak QE biofluorescence/microscopy imaging, day/night security and surveillance, and other high-end applications which require HD video imaging with high sensitivity and wide dynamic range. The camera comes with an array of lens mounts including C-mount and F-mount. The latest test data from the NV-CMOS HD camera will be presented.

  20. Application of minidisk infiltrometer to estimate soil water repellency

    Science.gov (United States)

    Alagna, Vincenzo; Iovino, Massimo; Bagarello, Vincenzo; Mataix-Solera, Jorge; Lichner, Ľubomír

    2016-04-01

    Soil water repellency (SWR) reduces affinity of soils to water resulting in detrimental implication for plants growth as well as for hydrological processes. During the last decades, it has become clear that SWR is much more widespread than formerly thought, having been reported for a wide variety of soils, land uses and climatic conditions. The repellency index (RI), based on soil-water to soil-ethanol sorptivity ratio, was proposed to characterize subcritical SWR that is the situation where a low degree of repellency impedes infiltration but does not prevent it. The minidisk infiltrometer allows adequate field assessment of RI inherently scaled to account for soil physical properties other than hydrophobicity (e.g., the volume, connectivity and the geometry of pores) that directly influence the hydrological processes. There are however some issues that still need consideration. For example, use of a fixed time for both water and ethanol sorptivity estimation may lead to inaccurate RI values given that water infiltration could be negligible whereas ethanol sorptivity could be overestimated due to influence of gravity and lateral diffusion that rapidly come into play when the infiltration process is very fast. Moreover, water and ethanol sorptivity values need to be determined at different infiltration sites thus implying that a large number of replicated runs should be carried out to obtain a reliable estimate of RI for a given area. Minidisk infiltrometer tests, conducted under different initial soil moisture and management conditions in the experimental sites of Ciavolo, Trapani (Italy) and Javea, Alicante (East Spain), were used to investigate the best applicative procedure to estimate RI. In particular, different techniques to estimate the water, Sw, and ethanol, Se, sorptivities were compared including i) a fixed 1-min time interval, ii) the slope of early-time 1D infiltration equation and iii) the two-term transient 3D infiltration equation that explicitly

  1. Solute leaching in a sandy soil with a water-repellent surface layer: a simulation.

    NARCIS (Netherlands)

    Rooij, de G.H.; Vries, de P.

    1996-01-01

    Many sandy soils in the Netherlands have a water-repellent surface layer covering a wettable soil with a shallow groundwater table. Fingers form in the water-repellent surface layer and rapidly transport water and solutes to the wettable soil in which the streamlines diverge. Although several field

  2. Odorant receptor modulation: Ternary paradigm for mode of action of insect repellents

    Science.gov (United States)

    The modulation of insect behavior for the purpose of controlling the spread of infectious diseases has been the task of a few insect repellents for which the mechanistic modes of action on odorant receptors (ORs) are unclear. Here, we study the effects of the repellents DEET and IR3535, and a novel ...

  3. Infodisruption of inducible anti-predator defenses through commercial insect repellents?

    Science.gov (United States)

    von Elert, Eric; Preuss, Katja; Fink, Patrick

    2016-03-01

    Commercial insect repellents like DEET (N,N-diethyl-m-toluamide), EBAAP (IR3535(®), (3-[N-butyl-N-acetyl]-aminopropionic acid, ethyl ester)) or Icaridine (picaridin, Bayrepel, 1-piperidinecarboxylic acid, 2-(2-hydroxyethyl), 1-methylpropyl ester) are used worldwide to protect against biting insects and ticks. The detection of these repellents in surface waters in concentrations up to several μg/L levels has caused concern that these substances might affect non-target organisms in freshwaters. Daphnia sp., a keystone organism in lakes and ponds, is known for diel vertical migration (DVM) and life-history changes (LHCs) as inducible defenses against predation by fish. Here we test whether (i) environmentally relevant concentrations of DEET, EBAPP or Icaridine have repellent effects on Daphnia magna and (ii) if these repellents are infodisruptors for DVM and LHCs. Using concentrations of up to 44 μg/L, the repellents neither had effects on juvenile somatic growth nor on clutch size. In thermally stratified water columns with a repellent-free hypolimnion, no repellent effects of the test compounds on D. magna were observed. The presence of fish-born infochemicals induced LHCs, which are characterized by a reduced size at first reproduction, and DVM in D. magna. These effects were not affected by the presence of either repellent. Hence no evidences for infodisruption of the chemical communication of fish and Daphnia by DEET, EBAAP or Icaridine were found.

  4. Neurophysiological and behavioral responses of gypsy moth larvae to insect repellents

    Science.gov (United States)

    The interactions between insect repellents and the olfactory system have been widely studied, however relatively little is known about the effects of repellents on the gustatory system of insects. In this study, we show that the gustatory receptor neuron (GRN) located in the medial styloconic sensi...

  5. Soil water repellency in an old and young pasture in relation to N application

    NARCIS (Netherlands)

    Sonneveld, M.P.W.

    2008-01-01

    Ageing of pastures is likely to affect the degree of potential water repellency in the long term, whereas seasonal variation on a shorter term affects the actual repellency of soils. A 1-year study on two pastures of different ages was conducted on a sandy soil to assess changes in the degree of

  6. Water repellency under natural conditions in sandy soils of southern Spain

    NARCIS (Netherlands)

    Moral García, F.J.; Dekker, L.W.; Oostindie, K.; Ritsema, C.J.

    2005-01-01

    The occurrence and consequences of fire-induced water repellency have been studied in several regions of Spain since 1989. The occurrence of water repellency formed under natural conditions, however, has only been described for a few areas in Spain since 1998. The purpose of the present study was to

  7. Improvement of Water Movement in an Undulating Sandy Soil Prone to Water Repellency

    NARCIS (Netherlands)

    Oostindie, K.; Dekker, L.W.; Wesseling, J.G.; Ritsema, C.J.

    2011-01-01

    The temporal dynamics of water repellency in soils strongly influence water flow. We investigated the variability of soil water content in a slight slope on a sandy fairway exhibiting water-repellent behavior. A time domain reflectometry (TDR) array of 60 probes measured water contents at 3-h

  8. Temporal fluctuations in soil water repellency following wildfire in chaparral steeplands, southern California

    Science.gov (United States)

    K.R. Hubbert; V. Oriol

    2005-01-01

    Soil water repellency is partularly common in unburned chaparral, and its degree and duration can be influenced by seasonal weather conditions. Water repellency tends to increase in dry soils, whil eit decreases or vanishes following precipitation or extended periods of soil moisture. The 15426 ha Williams Fire provided an opportunity to investigate post-fire...

  9. Water quality and surfactant effects on the water repellency of a sandy soil

    Science.gov (United States)

    Differences in irrigation water quality may affect the water repellency of soils treated or untreated with surfactants. Using simulated irrigations, we evaluated water quality and surfactant application rate effects upon the water repellency of a Quincy sand (Xeric Torripsamment). We used a split ...

  10. Water repellency and critical soil water content in a dune sand

    NARCIS (Netherlands)

    Dekker, L.W.; Doerr, S.H.; Oostindie, K.; Ziogas, A.K.; Ritsema, C.J.

    2001-01-01

    Assessments of water repellency of soils are commonly made on air-dried or oven-dried samples, without considering the soil water content. The objectives of this study were to examine the spatial and temporal variability of soil water content, actual water repellency over short distances, and the

  11. Pre- and postfire distribution of soil water repellency in a steep chaparral watershed

    Science.gov (United States)

    K. R. Hubbert; P. M. Wohlgemuth; H. K. Preisler

    2008-01-01

    The development and nature of water repellent soils and their spatial distribution on the landscape are not well understood relative to evaluating hillslope response to fire. Soil water repellency is particularly common in chaparral communities, due in part to the coarse-textured soils, and the high resin content of the organic litter. Objectives of this study were 1)...

  12. Surfactant seed coating - a strategy to improve turfgrass establishment on water repellent soils

    Science.gov (United States)

    Turfgrass managers can experience poor seeding success when trying to establish golf course greens and sports fields on water repellent soils. Nonionic soil surfactant formulations based on ethylene oxide-propylene oxide (EO/PO) block copolymers are commonly used to treat water repellent soils. Rece...

  13. In vitro repellency of DEET against the ticks Rhipicephalus sanguineus sensu lato and Amblyomma sculptum

    Science.gov (United States)

    Rhipicephalus sanguineus sensu lato and Amblyomma sculptum can parasite humans and domestic animals and are vectors of pathogens, including zoonoses. Repellents are an important tool of tick control. This study aimed to compare the efficacy of N,N-diethyl- 3-methylbenzamide (DEET), a standard repell...

  14. Comparative Study of Four Membranes for Evaluation of New Insect/Arthropod Repellents Using Aedes aegypti

    Science.gov (United States)

    2008-01-01

    test system, and (Armed Forces Pest Management Board. 1996) repellent potencial of the 3D pharmacophore- bascd newly designed and synthesized ten...ethyl- hexyl ester) Repellent test system: A modified inz:itro rest system was used to evaluate the potencial membrane altematives as shown in Fig. 1

  15. Measuring and understanding soil water repellency through novel interdisciplinary approaches

    Science.gov (United States)

    Balshaw, Helen; Douglas, Peter; Doerr, Stefan; Davies, Matthew

    2017-04-01

    Food security and production is one of the key global issues faced by society. It has become evermore essential to work the land efficiently, through better soil management and agronomy whilst protecting the environment from air and water pollution. The failure of soil to absorb water - soil water repellency - can lead to major environmental problems such as increased overland flow and soil erosion, poor uptake of agricultural chemicals and increased risk of groundwater pollution due to the rapid transfer of contaminants and nutrient leaching through uneven wetting and preferential flow pathways. Understanding the causes of soil hydrophobicity is essential for the development of effective methods for its amelioration, supporting environmental stability and food security. Organic compounds deposited on soil mineral or aggregate surfaces have long been recognised as a major factor in causing soil water repellency. It is widely accepted that the main groups of compounds responsible are long-chain acids, alkanes and other organic compounds with hydrophobic properties. However, when reapplied to sands and soils, the degree of water repellency induced by these compounds and mixtures varied widely with compound type, amount and mixture, in a seemingly unpredictable way. Our research to date involves two new approaches for studying soil wetting. 1) We challenge the theoretical basis of current ideas on the measured water/soil contact angle measurements. Much past and current discussion involves Wenzel and Cassie-Baxter models to explain anomalously high contact angles for organics on soils, however here we propose that these anomalously high measured contact angles are a consequence of the measurement of a water drop on an irregular non-planar surface rather than the thermodynamic factors of the Cassie-Baxter and Wenzel models. In our analysis we have successfully used a much simpler geometric approach for non-flat surfaces such as soil. 2) Fluorescent and phosphorescent

  16. A Modified Synthesis of the Insect Repellent DEET

    Science.gov (United States)

    Knoess, Peter H.; Neeland, Edward G.

    1998-10-01

    In the preparation of the insect repellent DEET, lab procedures prepare the intermediate m-toluoyl chloride by heating m-toluic acid with thionyl chloride for times ranging from 15 to 45 minutes. The acid chloride is then worked up under Schotten-Baumann conditions to yield DEET. In our students' hands, these procedures gave a darkly colored product which was contaminated with an anhydride by-product. We have shown that the m-toluoyl chloride can be prepared at room temperature in 8 minutes and that the eventual DEET product is obtained in excellent yield without the dark coloration or anhydride by-product.

  17. Breath figures of two immiscible substances on a repellent surface

    Science.gov (United States)

    Guadarrama-Cetina, J.; González-Viñas, W.

    2013-05-01

    The understanding of the competition between different substances while condensing on a cold surface is of high interest in situations in which it is desirable to control their condensation rates and the formed morphologies. We do the experiments for mixtures of water and hexamethyldisiloxane vapors at several concentrations. The dropwise condensation of the vapors forms breath figures on a substrate that is repellant to both substances. We report the average radius of the drops for each specie as a function of time. Also, we pay attention to the evolution of the corresponding morphologies and the appearance of hybrid clusters.

  18. Evaluation of Certain Insecticides and Repellents Against Ticks

    Directory of Open Access Journals (Sweden)

    D. Kapoor

    1972-07-01

    Full Text Available The susceptibility of two commonly occurring species of Ixodid ticks viz., the cattle tick, Hyalomma anatolicum anatolicum Koch and the brown dog tick, Rhipicephalus sanguineus Latr to certain newer insecticdes was investigated under controlled environmental conditions. The repellency of diethyl toluamide (Deet to the two species of ticks was also investigated by a specially devised laboratory technique. It was found that based on LC/sub 50/ values, the two species were most susceptible to pyrethrins followed by carbaryl whereas malathion was found least toxic to the ticks.

  19. Physicochemical characterization of fish protein adlayers with bacteria repelling properties

    DEFF Research Database (Denmark)

    Meyer, R. L.; Arpanaei, A.; Pillai, S.;

    2013-01-01

    Materials coated with aqueous fish protein extracts can reduce bacterial adhesion, but the mechanism behind the observed effect is not fully understood. In this study we explore the physicochemical properties of fish muscle protein adlayers on four substrates: gold, stainless steel, polystyrene...... and silicon dioxide. The aims were (i) to determine if the anti-adhesive effect is independent of the underlying substrate chemistry, (ii) to link the physicochemical properties of the adlayer to its ability to repel bacteria, and (iii) to elucidate the mechanism behind this effect. The main proteins on all...

  20. A thermodynamic geography: night-time satellite imagery as a proxy measure of emergy.

    Science.gov (United States)

    Coscieme, Luca; Pulselli, Federico M; Bastianoni, Simone; Elvidge, Christopher D; Anderson, Sharolyn; Sutton, Paul C

    2014-11-01

    Night-time satellite imagery enables the measurement, visualization, and mapping of energy consumption in an area. In this paper, an index of the "sum of lights" as observed by night-time satellite imagery within national boundaries is compared with the emergy of the nations. Emergy is a measure of the solar energy equivalent used, directly or indirectly, to support the processes that characterize the economic activity in a country. Emergy has renewable and non-renewable components. Our results show that the non-renewable component of national emergy use is positively correlated with night-time satellite imagery. This relationship can be used to produce emergy density maps which enable the incorporation of spatially explicit representations of emergy in geographic information systems. The region of Abruzzo (Italy) is used to demonstrate this relationship as a spatially disaggregate case.

  1. 75 FR 47592 - Final Test Guideline; Product Performance of Skin-applied Insect Repellents of Insect and Other...

    Science.gov (United States)

    2010-08-06

    ... AGENCY Final Test Guideline; Product Performance of Skin-applied Insect Repellents of Insect and Other... Product Performance of Skin-applied Insect Repellents of Insect and Other Arthropods Test Guidelines... ``Product Performance of Skin-applied Insect Repellents of Insects and Other Arthropods'' (OPPTS...

  2. Laboratory and semi-field evaluations of two (Transfluthrin) spatial repellent devices against Aedes aegypti (L.) (Diptera: Culicidae)

    Science.gov (United States)

    Two transfluthrin-based spatial repellent products (Raid Dual Action Insect Repellent and Home Freshener and Raid Shield (currently not commercially available), SC Johnson, Racine WI) were evaluated for spatial repellent effects against female Aedes aegypti (L.) mosquitoes underlaboratory (wind tunn...

  3. Use of repellents formulated in Specialized Pheromone and Lure Application Technology (SPLAT®) for effective insect pest management

    Science.gov (United States)

    Agenor Mafra-Neto; Christopher J. Fettig; A. Steven Munson; Lukasz L. Stelinski

    2014-01-01

    Despite the many impediments to commercialization of insect repellents in agriculture and forestry, there are some situations where the use of repellents is desirable and warranted. ISCA Technologies (Riverside, California), together with collaborators from academic, government, and private sectors, is actively developing repellent formulations against several...

  4. Geneva motorway bypass closed for two nights

    CERN Multimedia

    2006-01-01

    The carriageways heading towards France on the airport section of the motorway will be closed from 8.30 p.m. to 5.00 a.m. in the night of 1 to 2 October and those heading towards Lausanne during the same hours in the night of 2 to 3 October. This is to allow dry-surface road-marking and signage work to be performed. The work will be postponed in the event of bad weather, in which case the new date will be announced on Radio RSR and Radio Lac as well as on the telephone traffic news service 163. Diversions will be in operation. Thank you in advance for your understanding. For further information, tel. 163 or www.autoroute-aeroport.ch Civil Engineering Department, DCTI, State of Geneva

  5. Working night shifts affects surgeons' biological rhythm

    DEFF Research Database (Denmark)

    Amirian, Ilda; Andersen, Lærke T; Rosenberg, Jacob

    2015-01-01

    BACKGROUND: Chronic sleep deprivation combined with work during the night is known to affect performance and compromise residents' own safety. The aim of this study was to examine markers of circadian rhythm and the sleep-wake cycle in surgeons working night shifts. METHODS: Surgeons were monitored...... prospectively for 4 days: pre call, on call, post call day 1 (PC1), and post call day 2 (PC2). The urinary metabolite of melatonin and cortisol in saliva were measured to assess the circadian rhythm. Sleep and activity were measured by actigraphy. Subjective measures were assessed by the Karolinska Sleepiness...... Scale and Visual Analog Scale of fatigue, general well-being, and sleep quality. RESULTS: For both metabolite of melatonin and cortisol, a significant difference (P sleep time during the day on call...

  6. Statistical assessment of night vision goggle noise

    Science.gov (United States)

    Wales, Jesse G.; Marasco, Peter L.

    2006-05-01

    New advancements in charged-coupled device (CCD) technology allow for further investigation into the spatial nature of night vision goggle (NVG) noise distributions. This is significant because it is common practice in new NVG technology to combine image intensifiers with CCDs for night vision imaging. In this study, images of NVG noise are recorded by a CCD camera while varying input radiance and using multiple goggle types. Noise distributions characterized using histograms of these images are analyzed and fitted with curves. Using the changes in the distribution and relating distribution changes (coefficient changes) to input radiance and goggle performance provides a very accurate noise characterization. This study finds that a Weibull distribution seems more appropriate than a Poisson distribution, producing higher correlation coefficient fits. In addition, the paper suggests possible ways the noise models developed here can impact advancements in NVG image enhancement using this new technology.

  7. Illuminating the Nights in Rural Communities

    Directory of Open Access Journals (Sweden)

    Dr. Achara N

    2014-11-01

    Full Text Available Electric power supply in many cities in developing countries is erratic and can only be described as non-existent in the rural areas. Kerosene lantern, the main source of illuminating the night is associated with obnoxious fumes production and more especially the kerosene fuel is scarce to find. Rural dwellers who cannot afford the globed kerosene lanterns either use the locally fabricated globeless kerosene lanterns, ―atunja‖ or log fire. Log fire is associated with deforestation and desert encroachment. A solar lantern has been designed and built for illuminating the nights in rural communities. Battery and LED are part of the components used and it is recommended that appropriate safety measures are put in place not only in use but also in their disposal.

  8. The effect of land use on spatial variability of soil water repelency

    Science.gov (United States)

    Hrabovský, Andrej; Dlapa, Pavel; Chrenková, Katarína; Šimkovic, Ivan

    2016-04-01

    Soil water repellency was identified as a fundamental phenomenon during a soil survey dedicated to soil hydrological properties and processes in watersheds of the Little Carpathians Mts. (SW Slovakia). The investigated area represents the viticulture region with various soil management practices. Thus, soils of the region are influenced by deep ploughing during vineyard establishment, by cultivation of vineyards, by reforestation of abandoned vineyards as well as by long-term forestry practices. The soils developed from granitic rocks are naturally susceptible to water repellency development. The obtained results showed marked variability in physical and chemical soil properties. In particular, the soil pH values, the clay and organic carbon contents differed significantly depending on soil management. Due to these differences, the soil water repellency increased from wettable to extremely water repellent approximately in order: deeply ploughed vineyard soils water repellency on infiltration process was observed by means of field experiments.

  9. CMS Virtual Visit - Researchers Night in Portugal

    CERN Multimedia

    Abreu, Pedro

    2016-01-01

    Researchers Night at Planetarium Calouste Gulbenkian - Ciência Viva Centre in Lisbon. Organised by researchers from LIP (Laboratório de Instrumentação e Física Experimental de Partículas) and including CMS Virtual Visit during which André David Tinoco Mendes and José Rasteiro da Silva, based at Cessy, France, "virtually" discussed science and technology behind the CMS detector with the audience in Lisbon.

  10. The Mythology of the Night Sky

    Science.gov (United States)

    Falkner, David E.

    The word "planet" comes from the Latin word planeta and the Greek word planes, which means "wanderer." When the ancient Greeks studied the night sky they noticed that most of the stars remained in the same position relative to all the other stars, but a few stars seem to move in the sky from day to day, week to week, and month to month. The Greeks called these rogue stars "wanderers" because they wandered through the starry background.

  11. What's crucial in night vision goggle simulation ?

    OpenAIRE

    Kooi, F.L.; Toet, A

    2005-01-01

    Training is required to correctly interpret NVG imagery. Training night operations with simulated intensified imagery has great potential. Compared to direct viewing with the naked eye, intensified imagery is relatively easy to simulate and the cost of real NVG training is high (logistics, risk, civilian sleep deprivation, pollution). On the surface NVG imagery appears to have a structure similar to daylight imagery. However, in actuality its characteristics differ significantly from those of...

  12. The conformal transformation of the night sky

    Science.gov (United States)

    Minguzzi, E.

    2016-12-01

    We give a simple differential geometric proof of the conformal transformation of the night sky under change of observer. The proof does not use the four dimensionality of spacetime or spinor methods. Furthermore, it really shows that the result does not depend on Lorentz transformations. This approach, by giving a transparent covariant expression to the conformal factor, shows that in most situations it is possible to define a thermal sky metric independent of the observer.

  13. Sport Transition of JPSS VIIRS Imagery for Night-time Applications

    Science.gov (United States)

    Fuell, Kevin; LeRoy, Anita; Smith, Matt; Miller, Steve; Kann, Diedre; Bernhardt, David; Reydell, Nezette; Cox, Robert

    2014-01-01

    The NASA/Short-term Prediction, Research, and Transition (SPoRT) Program and NOAA/Cooperative Institute for Research in the Atmosphere (CIRA) work within the NOAA/Joint Polar Satellite System (JPSS) Proving Ground to demonstrate the unique capabilities of the VIIRS instrument. Very similar to MODIS, the VIIRS instrument provides many high-resolution visible and infrared channels in a broad spectrum. In addition, VIIRS is equipped with a low-light sensor that is able to detect light emissions from the land and atmosphere as well as reflected sunlight by the lunar surface. This band is referred to as the Day-Night Band due to the sunlight being used at night to see cloud and topographic features just as one would typically see in day-time visible imagery. NWS forecast offices that collaborate with SPoRT and CIRA have utilized MODIS imagery in operations, but have longed for more frequent passes of polar-orbiting data. The VIIRS instrument enhances SPoRT collaborations with WFOs by providing another day and night-time pass, and at times two additional passes due to its large swath width. This means that multi-spectral, RGB imagery composites are more readily available to prepare users for their use in GOES-R era and high-resolution imagery for use in high-latitudes is more frequently able to supplement standard GOES imagery within the SPoRT Hybrid GEO-LEO product. The transition of VIIRS also introduces the new Day-Night Band capability to forecast operations. An Intensive Evaluation Period (IEP) was conducted in Summer 2013 with a group of "Front Range" NWS offices related to VIIRS night-time imagery. VIIRS single-channel imagery is able to better analyze the specific location of fire hotspots and other land features, as well as provide a more true measurement of various cloud and aerosol properties than geostationary measurements, especially at night. Viewed within the SPoRT Hybrid imagery, the VIIRS data allows forecasters to better interpret the more frequent, but

  14. Agomelatine Efficacy in the Night Eating Syndrome

    Directory of Open Access Journals (Sweden)

    Walter Milano

    2013-01-01

    Full Text Available Night eating syndrome (NES is a nosographic entity included among the forms not otherwise specified (EDNOS in eating disorders (ED of the DSM IV. It is characterized by a reduced food intake during the day, evening hyperphagia, and nocturnal awakenings associated with conscious episodes of compulsive ingestion of food. Frequently, NES patients show significant psychopathology comorbidity with affective disorders. This paper describes a case report of an NES patient treated with agomelatine, an antidepressant analogue of melatonin, which acts by improving not only the mood but also by regulating sleep cycles and appetite. After three months of observation, the use of Agomelatine not only improved the mood of our NES patient (assessed in the HAM-D scores but it was also able to reduce the night eating questionnaire, by both reducing the number of nocturnal awakenings with food intake, the time of snoring, the minutes of movement during night sleep (assessed at polysomnography, and the weight (−5.5 kg and optimizing blood glucose and lipid profile. In our clinical case report, agomelatine was able both to reduce the NES symptoms and to significantly improve the mood of our NES patient without adverse side effects during the duration of treatment. Therefore, our case report supports the rationale for further studies on the use of Agomelatine in the NES treatment.

  15. The volunteer programme ‘Night Ravens’:

    DEFF Research Database (Denmark)

    Larsen, Britt Østergaard; Bendix Kleif, Helle; Kolodziejczyk, Christophe

    2015-01-01

    The volunteer programme ‘Night Ravens’ (NR) was founded in Sweden in 1987 and has, over the years, developed into a Scandinavian concept covering large areas of Sweden, Denmark, Norway, Greenland and the Faroe Islands. The NR programme is a crime prevention initiative with adults walking the stre......The volunteer programme ‘Night Ravens’ (NR) was founded in Sweden in 1987 and has, over the years, developed into a Scandinavian concept covering large areas of Sweden, Denmark, Norway, Greenland and the Faroe Islands. The NR programme is a crime prevention initiative with adults walking...... the streets at night in identifiable ‘uniforms’ in areas with high activity. The purpose of this study is to evaluate the effects of the NR programme in Denmark based on a volunteer set-up with a less intrusive approach to situational crime prevention than, for instance, hot spot policing. The analyses...... with NR organizations to districts without NR organizations. The results show no difference in the crime rates between Danish postcode districts with and without the NR programme. Hence, we cannot identify positive effects of situational crime prevention when evaluating this Scandinavian volunteer...

  16. Persepsi Wisatawan Terhadap Night Life Attraction

    Directory of Open Access Journals (Sweden)

    Hary Hermawan

    2017-04-01

    ABSTRACT Cabaret is a term performances of music, comedy, dance, drama, and other special mix of art perfomed by men who dressed in women (ladyboy on stage. Cabaret performances in Oyot Godhong Restaurant intended as new tourist attraction that is expected to increase the interest of tourists to visit Malioboro in Yogyakarta, especially to Oyot Godhong Restaurants. Based descriptive study shows that the characteristics travelers who viewed Kabaret show is very diverse, each of which has perceptions and motivations are different. Cabaret performances have qualified to become the cultural attractions are staged at night (night atraction in the city of Yogyakarta. Based on traveler perception indicates that the cabaret performances have beauty or aesthetics, uniqueness, and values that match the criteria criteria of the standard as a tourist attraction. Performances Cabaret in Oyot Godhong Restaurants able to increase the sale value. Oyot Godhong Restaurants previously only form of tourism facilities (amenities, but is now a restaurant that has a tourist attraction (atraction.   Keywords: Cabaret show, night life attractions, tourism attraction, tourists perception, tourism marketing

  17. Mothers' night work and children's behavior problems.

    Science.gov (United States)

    Dunifon, Rachel; Kalil, Ariel; Crosby, Danielle A; Su, Jessica Houston

    2013-10-01

    Many mothers work in jobs with nonstandard schedules (i.e., schedules that involve work outside of the traditional 9-5, Monday through Friday schedule); this is particularly true for economically disadvantaged mothers. In the present article, we used longitudinal data from the Fragile Families and Child Wellbeing Survey (n = 2,367 mothers of children ages 3-5 years) to examine the associations between maternal nonstandard work and children's behavior problems, with a particular focus on mothers' night shift work. We employed 3 analytic strategies with various approaches to adjusting for observed and unobserved selection factors; these approaches provided an upper and lower bound on the true relationship between night shift work and children's behavior. Taken together, the results provide suggestive evidence for modest associations between exposure to maternal night shift work and higher levels of aggressive and anxious or depressed behavior in children compared with children whose mothers who are not working, those whose mothers work other types of nonstandard shifts, and, for aggressive behavior, those whose mothers work standard shifts.

  18. Cancer treatment: dealing with hot flashes and night sweats

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000826.htm Cancer treatment: dealing with hot flashes and night sweats To ... this page, please enable JavaScript. Certain types of cancer treatments can cause hot flashes and night sweats. Hot ...

  19. Evaluation of Repellency Effect of Essential Oils of Satureja khuzestanica (Carvacrol, Myrtus communis (Myrtle, Lavendula officinalis and Salvia sclarea using Standard WHO Repellency Tests.

    Directory of Open Access Journals (Sweden)

    Mohammad Hassan Kayedi

    2014-06-01

    Full Text Available Using special lotions and repellent sprays on skin is one of the effective methods to prevent Arthropods biting which was verified in this study.Essential oils of four plants (Satureja khuzestanica, Salvia sclarea, Lavendula officinalis and Myrtus communis were separately extracted by Clevenger used hydro distillation method. Then separated solutions with 10%, 20% and 40% concentrations of essential oils of plants in 99.6 % ethanol were prepared. WHO guidelines for efficacy testing of mosquito repellents for human skin were used on different concentrations of essential oils of plants, traditional repellents (DEET, 50% and 33% as positive control, and ethanol 99.6% and naked hands as negative controls.In negative control groups, the number of bits were comparable (P= 0.42 and had decreasing time trends (naked hands P= 0.011, ethanol P< 0.001. In all time points, minimum bites were observed in traditional repellents and it was significantly less than the other groups (P< 0.001. The time trend in the number of bites in the other groups was positive and showed minimum number of bites in time zero in all groups. We also found that the concentration of repellents had association with the number of bites. The maximum and minimum numbers of bites were observed with 10% and 40% concentrations respectively in all groups.Essential oils of Salvia sclarea, Lavendula officinalis and Myrtus communis have repellency effect, even with 10% concentration of essential oils.

  20. Olfactory responses of the antennal trichoid sensilla to chemical repellents in the mosquito, Culex quinquefasciatus.

    Science.gov (United States)

    Liu, Feng; Chen, Li; Appel, Arthur G; Liu, Nannan

    2013-11-01

    Insect repellents are widely used to protect against insect bites and thus prevent allergic reaction and the spread of disease. To gain insight into the mosquito's response to chemicals repellents, we investigated the interaction between the olfactory system of the mosquito Culex quinquefasciatus Say and chemical repellents using single sensillum recording. The interactions of 50 repellent chemicals with olfactory receptor neurons were measured in six different types of mosquito sensilla: long sharp trichoid (LST), short sharp trichoid (SST), short blunt trichoid I (SBT-I), short blunt trichoid II (SBT-II), short blunt trichoid-curved (SBT-C), and grooved peg (GP). A single olfactory neuron reacted to the chemical repellents in each of the sensilla except for SBT-I and SBT-II, where two neurons were involved. Other than LST and GP, which showed no or very weak responses to the repellents tested, all the sensilla showed significant excitatory responses to certain types of repellents. Terpene-derived chemicals such as eucalyptol, α-pinene, and camphor, stimulated olfactory receptor neurons in a dose-dependent manner and mosquitoes responded more strongly to terpene-derived chemical repellents than to non-terpene-derived chemicals such as dimethyl phthalate. Mosquitoes also exhibited a similar response to stereoisomers of chemicals such as (-)-β-pinene versus (+)-β-pinene, and (-)-menthone versus (+)-menthone. This study not only demonstrates the effects of chemical repellents on the mosquito olfactory system but also provides important information that will assist those screening new mosquito repellents and designing new mosquito control agents.