WorldWideScience

Sample records for sunrise light intensity

  1. Orbital Sunrise

    Science.gov (United States)

    1994-01-01

    The STS-68 crew aboard the Space Shuttle Endeavour told a post-flight audience at JSC that this sunrise was one of the most scenic sunrises/ sunsets witnessed during the week and a half long Space Radar Laboratory (SRL-2) mission. Jutting clouds, back-lit by the dawn colors, are sandwiched between the blue airglow and the silhouetted horizon of Earth.

  2. Traffic light intensity meter, TIM®

    NARCIS (Netherlands)

    Leden, N. van der; Varkevisser, J.; Vroom, J. de; Oijen, T van

    2005-01-01

    The intensity of traffic lights decreases over time as a result of pollution and ageing. The Dutch Traffic Research Centre of the Ministry of Transport, Public Works and Water Management is searching for a convenient method for measuring the luminous intensity of traffic lights on the road, in order

  3. Perceiving the Intensity of Light

    Science.gov (United States)

    Purves, Dale; Williams, S. Mark; Nundy, Surajit; Lotto, R. Beau

    2004-01-01

    The relationship between luminance (i.e., the photometric intensity of light) and its perception (i.e., sensations of lightness or brightness) has long been a puzzle. In addition to the mystery of why these perceptual qualities do not scale with luminance in any simple way, "illusions" such as simultaneous brightness contrast, Mach bands,…

  4. Sunrise on Science.

    Science.gov (United States)

    Casto, James E.

    1994-01-01

    Sunrise Museum's Science Hall in Charleston, WV, offers 30 hands-on exhibits that introduce children to science. Museum programs use a 9-foot soft-sculptured, unzippable doll to teach children about nutrition and basic anatomy and recruit representatives from local businesses and industry to conduct weekend science workshops. (LP)

  5. Average Light Intensity Inside a Photobioreactor

    Directory of Open Access Journals (Sweden)

    Herby Jean

    2011-01-01

    Full Text Available For energy production, microalgae are one of the few alternatives with high potential. Similar to plants, algae require energy acquired from light sources to grow. This project uses calculus to determine the light intensity inside of a photobioreactor filled with algae. Under preset conditions along with estimated values, we applied Lambert-Beer's law to formulate an equation to calculate how much light intensity escapes a photobioreactor and determine the average light intensity that was present inside the reactor.

  6. Sunrise Mission Highlights

    CERN Document Server

    Riethmüller, Tino L

    2015-01-01

    Solar activity is controlled by the magnetic field, which also causes the variability of the solar irradiance that in turn is thought to influence the climate on Earth. The magnetic field manifests itself in the form of structures of different sizes, starting with sunspots (10-50 Mm) down to the smallest known magnetic features that often have spatial extents of 100 km or less. The study of the fine scale structure of the Sun's magnetic field has been hampered by the limited spatial resolution of the available observations. This has recently changed thanks to new space and ground-based telescopes. A significant step forward has been taken by the Sunrise observatory, built around the largest solar telescope to leave the ground, and containing two science instruments. Sunrise had two successful long-duration science flights on a stratospheric balloon in June 2009 (solar activity minimum) and in June 2013 (at a high activity level) and a number of scientific results have been obtained that have greatly advanced ...

  7. Sunrise, Earth Limb, SW Pacific Ocean

    Science.gov (United States)

    1992-01-01

    The colors of this sunrise/sunset scene provide insights into the relative density of the Earth's atmosphere (15.5S, 158.5E). This scene captures the silhouette of several thunderstorms with their cirrus anvil tops spreading out against the tropopause - the top of the lowest layer of atmosphere, the troposphere which is also the most dense and refracts light at the red end of the spectrum while the blues refract in the stratosphere, the highest layer.

  8. VISUAL ACUITY IN DIFFERENT INTENSITIES OF LIGHT

    Directory of Open Access Journals (Sweden)

    Shruthi

    2014-12-01

    Full Text Available : BACKGROUND: Visual acuity is the resolving power of eyes which enables to distinguish the details and shapes of the objects. It is influenced by the intensity (illumination of light falling on the object. Measuring visual acuity is a simple test in assessing-health of the eyes, the pathway and visual brain. Intact normal vision is mandatory for selection of posts related to driving and traffic services. Intactness of visual acuity is influenced by a number of factors and one among them is intensity of ambient light. Hence, this study is undertaken to assess optimum light intensity for better visual perception. AIM: To evaluate the association between visual acuity and intensity of light and the optimum intensity of light to carry out for better perception of vision. MATERIALS AND METHODS: 100 literate subjects - 50 males and 50 females between 15-45 years, act both as cases and controls. Subjects, instructed to read alphabets and numbers from Snellen chart in 15 watts, 20 watts, 40 watts, 60 watts, 100 watts, 200 watts were considered as the study group and the same subjects in this study in day light as controls. Chart was placed at 6m distance. Both right and left eyes were tested separately in dark room illuminated with controlled light intensities. Number of correct characters read were noted for different illuminations and compared with that of controls. RESULTS: Reduced illumination significantly increased the no of incorrect choices and was statistically significant (P < 0.05 between 15 - 100 W. Visual acuity was best in 200 W in comparison with day light but was not statistically significant. However Visual acuity showed no significant difference between males and females for different intensities of light.

  9. [Sunrise gold foil jacket crown].

    Science.gov (United States)

    Lecardonnel, A

    1989-09-01

    This technique permits the preparation of ceramic jacket crowns made on Sunrise laminated precious metal alloy. The Sunrise foil is gold-colored, made of 99% of precious metals and is 50 microns thick. The die is prepared in order to display a moderate and regular undercut beyond the cervical limit. The margin will be underlined with a red pencil. The Sunrise foil is cut according to predetermined templates. Then the foil is applied without burnishing, according to the technique of jacket crowns on platinum foil only by finger pressure. The double folding on closure is preferably done distally or mesially. Then, the metal base is disinserted, sandblasted with 100 microns aluminum oxide, replaced on its die, and placed in a rubber casing before being placed in the isostatic press, to be subjected to a pressure of 2,000 TSI (14 kg par cm2). Sunrise's orange color reinforces rather subtetly the overall color, making these reconstructions particularly esthetic. The color of the Sunrise metal does not require, therefore a too thick opaque. Any ceramic intended to be fired on a metal base, may be used in respecting its firing protocol. Sunrise, as any other technique of this type, require a careful preparation with a shoulder that has a rounded gingivoaxial line angle. Bridges may be built on the "thimbles" crowns, fitted on Sunrise cores, the pontics being made as a ceramo-metal framework.

  10. Dynamic light intensity detection system of aerodrome assistance light

    Science.gov (United States)

    Gao, Jianshu; Song, Jiye; Yu, Zhijing; Chen, Fei; Shi, Xudong; Gao, Qingji

    2007-11-01

    The techniques used in dynamic detection of airfield lighting intensity are introduced in this paper. These techniques can take place of the old method of checking all manually, and the system can detect the lights intensity online quickly and exactly, so as to find out the light faults and ensure the safety of planes taking off, landing and slipping. The system uses a car with a string of sensors which have been cosine calibrated and v(λ) calibrated to detect the light intensity. When the car is moving, the sensors can detect the lights' horizontal section. To accurately measure the distance from the measured aerodrome assistance light to the moving car, and then calculate the light intensity and protract the iso-candela curve, the Doppler ranging radar system is used. To guarantee the dependability of the system and the measurement precision, a video monitoring and guiding system is used to assure the car to run along the airfield lights line, then light orientation sensors are used to eliminate the radar's cumulating errors. The experiment indicates that this system is feasible and has high detecting precision.

  11. Martian Sunrise at Utopia Planitia

    Science.gov (United States)

    1978-01-01

    A Martian sunrise was captured in this Viking 2 Lander picture taken June 14, 1978, at the spacecraft's Utopia Planitia landing site. The data composing this image were acquired just as the Sun peaked over the horizon on the Lander's 631st sol (Martian solar day). Pictures taken at dawn (or dusk) are quite dark except where the sky is brightened above the Sun's position. The glow in the sky results as light from the Sun is scattered and preferentially absorbed by tiny particles of dust and ice in the atmosphere. When the Viking cameras are calibrated for darker scenes, the 'sky glow' tends to saturate their sensitivity and produce the bright regions seen here. The 'banding' and color separation effects are also artifacts, rather than real features, and are introduced because the cameras are not able to record continuous gradations of light. The cameras must represent such gradations in steps (bands) of brightness and color, and the process sometimes produces some 'false' colors within the bands. The scattering of light closest to the Sun's position tends to enhance blue wavelengths. The narrowing sky glow nearer the horizon above the Sun's position occurs as a result of light extinction. At that elevation, the optical path of sunlight through the atmosphere is at its longest penetration angle, and a substantial portion of the light is simply prevented from reaching the cameras by the dust, ice particles and other material in its way.NASA's Langley Research Center was the primary and extended mission manager; JPL assumed management for continued mission operations.

  12. Light intensity of 5 or 20 lux on broiler behavior, welfare and productivity.

    Science.gov (United States)

    Rault, Jean-Loup; Clark, Katie; Groves, Peter J; Cronin, Greg M

    2017-04-01

    Light intensity can influence broiler behavior, but discrepancies in the scientific literature remain. Furthermore, few studies have investigated the welfare implications induced by varying light intensity. We investigated the effects of providing 5 or 20 lux light intensity on broiler behavior, welfare and productivity. A total of 1,872 Ross 308 broilers of mixed sex were studied across 2 replicates. Treatments began on d 8 with one of 2 light intensity levels: 5 lux or 20 lux, using LED lights on a 16L:8D photoperiod with 30 min sunrise and sunset periods. Production data, behavioral activity, and plasma samples for corticosterone concentration analysis were collected weekly from 8 to 46 d of age. Eye weight was collected at 42 d of age. Leg strength was assessed at 35, 42 and 45 d of age using the latency to lie test and leg and foot conditions (foot pad dermatitis, hock burn, leg straightness) were assessed at 46 d. Live weight differed between light treatments, with broilers kept at 20 lux being lighter than broilers kept at 5 lux at 46 d of age (males: -5.1%, females: -2.8%, P lux were more active during the photophase than broilers kept at 5 lux throughout the rearing period (P lux compared to 5 lux (P = 0.001). Nonetheless, there was no significant effect of light intensity on other measures of broiler welfare: mortality and culls, plasma corticosterone concentrations, or latency to lie reflective of leg strength. Hence, broilers kept at 20 lux compared to 5 lux were found to be more active, had slower growth, and had lighter eye weight, but other welfare measures reflective of biological functioning or leg health did not show significant changes.

  13. Forgotten Sunrise "Forgotten Sunrise. Behind The Abysmal Sky / Forever Sleeping Greystones". "The Moments When God Was Wrong" / Siim Nestor

    Index Scriptorium Estoniae

    Nestor, Siim, 1974-

    2009-01-01

    Arvustus: Forgotten Sunrise. Behind The Abysmal Sky / Forever Sleeping Greystones. [Tallinn] : Nailboard, 2009. Forgotten Sunrise. The Moments When God Was Wrong. [Tallinn] : Forgotten Sunrise, 2009. Uutest heliplaatidest

  14. Forgotten Sunrise "Forgotten Sunrise. Behind The Abysmal Sky / Forever Sleeping Greystones". "The Moments When God Was Wrong" / Siim Nestor

    Index Scriptorium Estoniae

    Nestor, Siim, 1974-

    2009-01-01

    Arvustus: Forgotten Sunrise. Behind The Abysmal Sky / Forever Sleeping Greystones. [Tallinn] : Nailboard, 2009. Forgotten Sunrise. The Moments When God Was Wrong. [Tallinn] : Forgotten Sunrise, 2009. Uutest heliplaatidest

  15. Intense, ultrashort light and dense, hot matter

    Indian Academy of Sciences (India)

    G Ravindra Kumar

    2009-07-01

    This article presents an overview of the physics and applications of the interaction of high intensity laser light with matter. It traces the crucial advances that have occurred over the past few decades in laser technology and nonlinear optics and then discusses physical phenomena that occur in intense laser fields and their modeling. After a description of the basic phenomena like multiphoton and tunneling ionization, the physics of plasma formed in dense matter is presented. Specific phenomena are chosen for illustration of the scientific and technological possibilities – simulation of astrophysical phenomena, relativistic nonlinear optics, laser wakefield acceleration, laser fusion, ultrafast real time X-ray diffraction, application of the particle beams produced from the plasma for medical therapies etc. A survey of the Indian activities in this research area appears at the end.

  16. Lasers and Intense Pulsed Light Hidradenitis Suppurativa.

    Science.gov (United States)

    Saunte, Ditte M; Lapins, Jan

    2016-01-01

    Lasers and intense pulsed light (IPL) treatment are useful for the treatment of hidradenitis suppurativa (HS). Carbon dioxide lasers are used for cutting or vaporization of the affected area. It is a effective therapy for the management of severe and recalcitrant HS with persistent sinus tract and scarring, and can be performed under local anesthesia. HS has a follicular pathogenesis. Lasers and IPL targeting the hair have been found useful in treating HS by reducing the numbers of hairs in areas with HS. The methods have few side effects, but the studies are preliminary and need to be repeated.

  17. Vitiligo following intense pulsed light treatment.

    Science.gov (United States)

    Shin, Jung U; Roh, Mi Ryung; Lee, Ju Hee

    2010-07-01

    Vitiligo is an acquired depigmenting disorder characterized by the progressive loss of melanocytes from the epidermis and epidermal appendages, which results in milky-white macular lesions. Various factors are suspected to affect the induction and progression of vitiligo such as emotional shock, sunburn, pregnancy, physical illness and trauma. The intense pulsed light (IPL) device which mostly affects redness and dyspigmentation has a broad spectrum of emissions of white light with wavelengths between approximately 515 and 1200 nm. Adverse effects such as purpura and pigmentary changes are known to be rare. We present a 41-year-old woman who developed multiple round, hypopigmented macules on both the cheek and mandibular area following the treatment with IPL for lentigines and dyspigmentation. Based on biopsy and Wood's lamp examination, diagnosis as vitiligo was made. She was treated with a 308-nm excimer laser. After 3 months of treatment, almost complete repigmentation was seen but another coin-sized hypopigmented patch was noted after 5 months later. Herein, we report a case of vitiligo which developed after IPL treatment. This is the first case to be reported which vitiligo developed after IPL treatment. Therefore, dermatologists should be aware of unsighted vitiligo lesion before IPL treatment.

  18. Design of Greenhouse Temperature and Light Intensity Control Circuit

    Institute of Scientific and Technical Information of China (English)

    Chao; ZHANG

    2014-01-01

    In view of domestic scientific and technological achievements at present,real-time control circuit for greenhouse temperature and light intensity has been designed in line with the principle of cost saving and easy control.With advanced temperature sensor and light sensor applied to measure the temperature and light intensity,an execution unit is controlled by single-chip microcomputer(SCM)to regulate the temperature and light intensity,creating a hardware design scheme and software design idea.In case of high temperature and high light intensity in greenhouse,the sunshade net will be put down and the blower will be started automatically;in case of low temperature and light intensity,the sunshade net will be folded up and the heating valve will be turned up automatically.In this way,the temperature and light intensity in greenhouse will be controlled within the designed range.

  19. Unconventional Use of Intense Pulsed Light

    Directory of Open Access Journals (Sweden)

    D. Piccolo

    2014-01-01

    Full Text Available According to the literature, intense pulsed light (IPL represents a versatile tool in the treatment of some dermatological conditions (i.e., pigmentation disorders, hair removal, and acne, due to its wide range of wavelengths. The authors herein report on 58 unconventional but effective uses of IPL in several cutaneous diseases, such as rosacea (10 cases, port-wine stain (PWS (10 cases, disseminated porokeratosis (10 cases, pilonidal cyst (3 cases, seborrheic keratosis (10 cases, hypertrophic scar (5 cases and keloid scar (5 cases, Becker’s nevus (2 cases, hidradenitis suppurativa (2 cases, and sarcoidosis (1 case. Our results should suggest that IPL could represent a valid therapeutic support and option by providing excellent outcomes and low side effects, even though it should be underlined that the use and the effectiveness of IPL are strongly related to the operator’s experience (acquired by attempting at least one specific course on the use of IPL and one-year experience in a specialized centre. Moreover, the daily use of these devices will surely increase clinical experience and provide new information, thus enhancing long-term results and improving IPL effectiveness.

  20. Intense Pulsed Light (IPL) in Aesthetic Dermatology

    Science.gov (United States)

    Pytras, B.; Drozdowski, P.; Zub, K.

    2011-08-01

    Introduction. Newer and newer technologies have been widely developed in recent years due to increasing need for aesthetic medicine procedures. Less invasive methods of skin imperfection and time-related lesions removal, IPL (Intense Pulse Light) being one of them, are gaining more and more interest. The shorter the "downtime" for the patient is and the more efficient the procedure results, the more popular the method becomes. Materials and methods_Authors analyse the results of treatment of a 571 patients-group (501 women and 70 men) aged 5-72 years in the period: October 2006-August 2010. IPL™ Quantum (Lumenis Ltd.) device with 560 nm. cut-off filter was used. Results. The results were regarded as: very good, good or satisfying (%):Skin photoaging symptomes 37/40/23, Isolated facial dyschromia 30/55/25, Isolated facial erythema 62/34/4, Lower limbs teleangiectasia 12/36/52, Keratosis solaris on hands 100/-/-. Approximately half of the patients developed transitory erythema and 25%- transitory, mild, circumscribed oedema. Following undesirable effects were noted: skin thermal irritation (6,1% of the patients) and skin hypopigmentation (2% of the patients). Discussion. Results and post-treatment management proposed by authors are similar to those reported by other authors. Conclusions. Treatment results of the 571-patients group prove IPL to be a very efficient method of non-ablative skin rejuvenation. It turned out effective also in lower limbs teleangiectasia treatment. It presents low risk of transitory and mild side effects. Futhermore, with short or no downtime, it is well-tolerated by the patients.

  1. effect of light intensity on the cure characteristics of photo ...

    African Journals Online (AJOL)

    2012-05-05

    May 5, 2012 ... Design: A laboratory based cross sectional study. Setting: Public and ... set out to determine the light intensity emitted by light curing units ... polymerised with it. MATERIAL AND METHODS ..... J. of Oral Rehab. 2005; 32:.

  2. Effects of the El Chichon volcanic cloud in the stratosphere on the intensity of light from the sky.

    Science.gov (United States)

    Coulson, K L

    1983-08-01

    This is the second of two papers dealing with the effects of volcanic debris from the eruption of El Chichon on light from the sunlit sky. The polarization of skylight was considered in the first of the two, whereas this one is devoted to skylight intensity. It is shown here that the magnitude of the skylight intensity is modified very significantly from its clear sky value by the volcanic cloud, as is its change with solar depression angle during twilight and its distribution over the sky during the day. Emphasis is on measurements at a wavelength of 0.07 microm. Generally the volcanic cloud produces a diminution of zenith intensity during twilight with a considerable enhancement of intensity over the sky throughout the main part of the day. The solar aureole is not as sharp as it is in normally clear conditions, but the volcanic cloud causes a very diffuse type of aureole which covers a large portion of the sky. The preferential scattering of the longer wavelengths of sunlight, which is made evident by brilliant red and yellow colors in the sunrise period, causes a pronounced change of longwave/shortwave color ratios during twilight from their values in clear atmospheric conditions. The combination of intensity data shown here with polarization data in the previous paper should give a relatively complete picture of the effects of volcanic debris on solar radiation in the atmosphere and be useful in the verification of radiative transfer models of atmospheric turbidity.

  3. IR microscopy utilizing intense supercontinuum light source

    DEFF Research Database (Denmark)

    Dupont, Sune; Petersen, Christian; Thøgersen, Jan;

    2012-01-01

    . The supercontinuum light source has a high brightness and spans the infrared region from 1400 nm to 4000 nm. This combination allows contact free high resolution hyper spectral infrared microscopy. The microscope is demonstrated by imaging an oil/water sample with 20 μm resolution.......Combining the molecular specificity of the infrared spectral region with high resolution microscopy has been pursued by researchers for decades. Here we demonstrate infrared supercontinuum radiated from an optical fiber as a promising new light source for infrared microspectroscopy...

  4. Sunrise deploys mobile network for CERN

    CERN Multimedia

    2004-01-01

    Sunrise, the alternative telecoms provider in Switzerland, is finalizing the installation of a mobile network comprising about forty sites located around the new particle accelerator at CERN (1 paragraph)

  5. Sunrise over Mars - electronic transmission

    Science.gov (United States)

    1976-01-01

    Caption: 'Taken during the Viking Orbiter 1's 40th revolution of Mars, this electronically transmitted image shows sunrise over the tributary canyons of a high plateau region. The white areas are bright clouds of water ice.' As the sun rises over Noctis Labryinthus (the labyrinth of the night), bright clouds of water ice can be observed in and around the tributary canyons of this high plateau region of Mars. This color composite image, reconstructed from three individual black and white frames taken through violet, green, and orange filters, vividly shows the distribution of the clouds against the rust colored background of this Martian desert. The picture was reconstructed by JPL's Image Processing Laboratory using in-flight calibration data to correct the color balance. Scientists have puzzled why the clouds cling to the canyon areas and, only in certain areas, spill over onto the plateau surface. One possibility is that water which condensed during the previous afternoon in shaded eastern-facing slopes of the canyon floor is vaporized as the early morning sun falls on those same slopes. The area covered is about 10,000 square kilometers (4000 square miles), centered at 9 degrees South, 95 degrees West, and the large partial crater at lower right is Oudemans. The picture was taken on Viking Orbiter 1's 40th revolution of the planet. Photograph and caption published in Winds of Change, 75th Anniversary NASA publication (pages 108-109), by James Schultz.

  6. Measurement of Dynamic Light Scattering Intensity in Gels

    CERN Document Server

    Rochas, Cyrille

    2015-01-01

    In the scientific literature little attention has been given to the use of dynamic light scattering (DLS) as a tool for extracting the thermodynamic information contained in the absolute intensity of light scattered by gels. In this article we show that DLS yields reliable measurements of the intensity of light scattered by the thermodynamic fluctuations, not only in aqueous polymer solutions, but also in hydrogels. In hydrogels, light scattered by osmotic fluctuations is heterodyned by that from static or slowly varying inhomogeneities. The two components are separable owing to their different time scales, giving good experimental agreement with macroscopic measurements of the osmotic pressure. DLS measurements in gels are, however, tributary to depolarised light scattering from the network as well as to multiple light scattering. The paper examines these effects, as well as the instrumental corrections required to determine the osmotic modulus. For guest polymers trapped in a hydrogel the measured intensity...

  7. effect of light curing unit characteristics on light intensity output ...

    African Journals Online (AJOL)

    2013-09-09

    Sep 9, 2013 ... Objective: To determine the characteristics of light curing units (LCUs) in dental clinics in Nairobi and ... generation which has dogged the new generation of. LEDs without ..... Knezevic A, Tarle Z, Meniga A, Sutalo J, Pichler G.

  8. Response of Cassava canopy to mid-day pseudo sunrise induced by solar eclipse.

    Science.gov (United States)

    Latha, R; Murthy, B S

    2013-07-01

    Variations in CO(2) concentration over a cassava canopy were measured during a solar eclipse at Thiruvananthapuram, India. The analysis presented attempts to differentiate between the eclipse effect and the possible effect of thick clouds, taking CO(2) as a proxy for photosynthesis. CO(2) and water vapor were measured at a rate of 10 Hz, and radiation at 1 Hz, together with other meteorological parameters. A rapid reduction in CO(2) observed post-peak eclipse, due apparently to intense photosynthesis, appears similar to what happens at daybreak/post-sunrise. The increase in CO(2) (4 ppm) during peak eclipse, with radiation levels falling below the photosynthesis cut-off for cassava, indicates domination of respiration due to the light-limiting conditions.

  9. Response of Cassava canopy to mid-day pseudo sunrise induced by solar eclipse

    Science.gov (United States)

    Latha, R.; Murthy, B. S.

    2013-07-01

    Variations in CO2 concentration over a cassava canopy were measured during a solar eclipse at Thiruvananthapuram, India. The analysis presented attempts to differentiate between the eclipse effect and the possible effect of thick clouds, taking CO2 as a proxy for photosynthesis. CO2 and water vapor were measured at a rate of 10 Hz, and radiation at 1 Hz, together with other meteorological parameters. A rapid reduction in CO2 observed post-peak eclipse, due apparently to intense photosynthesis, appears similar to what happens at daybreak/post-sunrise. The increase in CO2 (4 ppm) during peak eclipse, with radiation levels falling below the photosynthesis cut-off for cassava, indicates domination of respiration due to the light-limiting conditions.

  10. Performance analysis of solar cell arrays in concentrating light intensity

    Institute of Scientific and Technical Information of China (English)

    Xu Yongfeng; Li Ming; Wang Liuling; Lin Wenxian; Xiang Ming; Zhang Xinghua; Wang Yunfeng; Wei Shengxian

    2009-01-01

    tage in concentrating light intensity. The output power has a -20 W/V coefficient and so cooling fluid must be used. Both heat energy and electrical power are then obtained with a solar trough concentrating photovoltaic/thermal system.

  11. Remote Controlling of Light Intensity Using Phone Devices

    Directory of Open Access Journals (Sweden)

    Beza Negash Getu

    2015-08-01

    Full Text Available In this study, we investigate the design and simulation of an electronic system for remote controlling the level of light intensity of an electrical lighting system used for a certain desired application. The remote controlling is done using the keypad of any Dual Tone Multi Frequency (DTMF based telephone handset. A DTMF tone command sent from a transmitting fixed or mobile phone terminal will be used to activate a system of relays that control the required level of light intensity. An appropriate active bandpass filters are designed for recognition of the DTMF tones of the transmitted digit. The bandpass filters and the additional subsequent stages of the overall electronic system are simulated and tested using MULTISM. Light intensity controlling is useful to avoid unnecessary electrical power wastage and the remote controlling eliminates the physical presence of a person for adjusting the required level of lighting at the desired location.

  12. LED intense headband light source for fingerprint analysis

    Energy Technology Data Exchange (ETDEWEB)

    Villa-Aleman, Eliel

    2005-03-08

    A portable, lightweight and high-intensity light source for detecting and analyzing fingerprints during field investigation. On-site field analysis requires long hours of mobile analysis. In one embodiment, the present invention comprises a plurality of light emitting diodes; a power source; and a personal attachment means; wherein the light emitting diodes are powered by the power source, and wherein the power source and the light emitting diodes are attached to the personal attachment means to produce a personal light source for on-site analysis of latent fingerprints. The present invention is available for other applications as well.

  13. LED intense headband light source for fingerprint analysis

    Science.gov (United States)

    Villa-Aleman, Eliel

    2005-03-08

    A portable, lightweight and high-intensity light source for detecting and analyzing fingerprints during field investigation. On-site field analysis requires long hours of mobile analysis. In one embodiment, the present invention comprises a plurality of light emitting diodes; a power source; and a personal attachment means; wherein the light emitting diodes are powered by the power source, and wherein the power source and the light emitting diodes are attached to the personal attachment means to produce a personal light source for on-site analysis of latent fingerprints. The present invention is available for other applications as well.

  14. Laser and intense pulsed light hair removal technologies

    DEFF Research Database (Denmark)

    Haedersdal, M; Beerwerth, F; Nash, J F

    2011-01-01

    Light-based hair removal (LHR) is one of the fastest growing, nonsurgical aesthetic cosmetic procedures in the United States and Europe. A variety of light sources including lasers, e.g. alexandrite laser (755 nm), pulsed diode lasers (800, 810 nm), Nd:YAG laser (1064 nm) and broad-spectrum intense...

  15. Carcinogenesis related to intense pulsed light and UV exposure

    DEFF Research Database (Denmark)

    Hedelund, L; Lerche, C; Wulf, H C;

    2006-01-01

    This study examines whether intense pulsed light (IPL) treatment has a carcinogenic potential itself or may influence ultraviolet (UV)-induced carcinogenesis. Secondly, it evaluates whether UV exposure may influence IPL-induced side effects. Hairless, lightly pigmented mice (n=144) received three...

  16. Relationship between normalized light intensity and attenuated total reflection ratio

    Institute of Scientific and Technical Information of China (English)

    Yingcai Wu; Zhengtian Gu

    2008-01-01

    Attenuated total reflection (ATR) ratio is usually utilized to study the properties of surface plasmon resonance (SPR) sensors. The relationship between normalized light intensity and ATR ratio is investigated, and a modification coefficient is put forward to describe the relationship. A mathematical expression is built up for the coefficient based on Fresnel principle. The result shows that the ATR ratio, which cannot be measured directly in experiments, can be determined with the coefficient and the normalized intensity of light. The characteristic of the coefficient is also discussed.

  17. Laser and intense pulsed light hair removal technologies

    DEFF Research Database (Denmark)

    Haedersdal, M; Beerwerth, F; Nash, J F

    2011-01-01

    Light-based hair removal (LHR) is one of the fastest growing, nonsurgical aesthetic cosmetic procedures in the United States and Europe. A variety of light sources including lasers, e.g. alexandrite laser (755 nm), pulsed diode lasers (800, 810 nm), Nd:YAG laser (1064 nm) and broad-spectrum intense...... and discuss the efficacy and human safety implications of home-use devices....

  18. The sunrise integral and elliptic polylogarithms

    CERN Document Server

    Adams, Luise; Weinzierl, Stefan

    2016-01-01

    We summarize recent computations with a class of elliptic generalizations of polylogarithms, arising from the massive sunrise integral. For the case of arbitrary masses we obtain results in two and four space-time dimensions. The iterated integral structure of our functions allows us to furthermore compute the equal mass case to arbitrary order.

  19. Dynamics of fluid and light intensity in mechanically stirred photobioreactor.

    Science.gov (United States)

    Zhang, T

    2013-10-10

    Turbulent flows in a single-stage and a two-stage impeller-stirred photobioreactor with a simple geometric configuration were analyzed using computational fluid dynamics. The trajectories of the microorganisms entrained in the flow field were traced by the particle tracking method. By projecting these trajectories onto a radial-axial (r-z) plane with a given azimuth angle, we were able to observe four different dynamics zones: circulation, pure rotation, trap, and slow-motion. Within the pure rotation zone, turbulence can be observed near the edges of the impeller. The light intensity and the light/dark cycles subjected by the microorganisms differ significantly in these zones. These differences can be further changed by providing different incident light illuminations on the reactor surface. The dynamics zones can be altered by modifying the geometric configuration of the reactor and the impeller stirring mechanism. In combination with the utilization of different incident light illuminations, the light intensity dynamics and the light/dark cycles subjected by the microorganisms can be controlled such that an optimal photobioreactor design with a high efficiency of light utilization and a high formation rate of the biochemical products can be realized.

  20. Battery Charge Affects the Stability of Light Intensity from Light-emitting Diode Light-curing Units.

    Science.gov (United States)

    Tongtaksin, A; Leevailoj, C

    This study investigated the influence of battery charge levels on the stability of light-emitting diode (LED) curing-light intensity by measuring the intensity from fully charged through fully discharged batteries. The microhardness of resin composites polymerized by the light-curing units at various battery charge levels was measured. The light intensities of seven fully charged battery LED light-curing units-1) LY-A180, 2) Bluephase, 3) Woodpecker, 4) Demi Plus, 5) Saab II, 6) Elipar S10, and 7) MiniLED-were measured with a radiometer (Kerr) after every 10 uses (20 seconds per use) until the battery was discharged. Ten 2-mm-thick cylindrical specimens of A3 shade nanofilled resin composite (PREMISE, Kerr) were prepared per LED light-curing unit group. Each specimen was irradiated by the fully charged light-curing unit for 20 seconds. The LED light-curing units were then used until the battery charge fell to 50%. Specimens were prepared again as described above. This was repeated again when the light-curing units' battery charge fell to 25% and when the light intensity had decreased to 400 mW/cm(2). The top/bottom surface Knoop hardness ratios of the specimens were determined. The microhardness data were analyzed by one-way analysis of variance with Tukey test at a significance level of 0.05. The Pearson correlation coefficient was used to determine significant correlations between surface hardness and light intensity. We found that the light intensities of the Bluephase, Demi Plus, and Elipar S10 units were stable. The intensity of the MiniLED unit decreased slightly; however, it remained above 400 mW/cm(2). In contrast, the intensities of the LY-A180, Woodpecker, and Saab II units decreased below 400 mW/cm(2). There was also a significant decrease in the surface microhardnesses of the resin composite specimens treated with MiniLED, LY-A180, Woodpecker, and Saab II. In conclusion, the light intensity of several LED light-curing units decreased as the battery was

  1. Crystalline silicon cell performance at low light intensities

    NARCIS (Netherlands)

    Reich, N.H.|info:eu-repo/dai/nl/30483453X; van Sark, W.G.J.H.M.|info:eu-repo/dai/nl/074628526; Alsema, E.A.|info:eu-repo/dai/nl/073416258; Lof, R.W.; Schropp, R.E.I.|info:eu-repo/dai/nl/072502584; Sinke, W.C.|info:eu-repo/dai/nl/071641009; Turkenburg, W.C.|info:eu-repo/dai/nl/073416355

    2009-01-01

    Measured and modelled JV characteristics of crystalline silicon cells below one sun intensity have been investigated. First, the JV characteristics were measured between 3 and 1000 W/m2 at 6 light levels for 41 industrially produced mono- and multi-crystalline cells from 8 manufacturers, and at 29 i

  2. Increased collection efficiency of LIFI high intensity electrodeless light source

    Science.gov (United States)

    Hafidi, Abdeslam; DeVincentis, Marc; Duelli, Markus; Gilliard, Richard

    2008-02-01

    Recently, RF driven electrodeless high intensity light sources have been implemented successfully in the projection display systems for HDTV and videowall applications. This paper presents advances made in the RF waveguide and electric field concentrator structures with the purpose of reducing effective arc size and increasing light collection. In addition, new optical designs are described that further improve system efficiency. The results of this work demonstrate that projection system light throughput is increased relative to previous implementations and performance is optimized for home theater and other front projector applications that maintain multi-year lifetime without re-lamping, complete spectral range, fast start times and high levels of dynamic contrast due to dimming flexibility in the light source system.

  3. SiPM response to long and intense light pulses

    Science.gov (United States)

    Vinogradov, S.; Arodzero, A.; Lanza, R. C.; Welsch, C. P.

    2015-07-01

    Recently Silicon Photomultipliers (SiPMs) have become well recognized as the detector of choice for various applications which demand good photon number resolution and time resolution of short weak light pulses in the nanosecond time scale. In the case of longer and more intensive light pulses, SiPM performance gradually degrades due to dark noise, afterpulsing, and non-instant cell recovering. Nevertheless, SiPM benefits are expected to overbalance their drawbacks in applications such as X-ray cargo inspection using Scintillation-Cherenkov detectors and accelerator beam loss monitoring with Cherenkov fibres, where light pulses of a microsecond time scale have to be detected with good amplitude and timing resolution in a wide dynamic range of 105-106. This report is focused on transient characteristics of a SiPM response on a long rectangular light pulse with special attention to moderate and high light intensities above the linear dynamic range. An analytical model of the transient response and an initial consideration of experimental results in comparison with the model are presented.

  4. SiPM response to long and intense light pulses

    Energy Technology Data Exchange (ETDEWEB)

    Vinogradov, S., E-mail: Sergey.Vinogradov@liverpool.ac.uk [University of Liverpool and Cockcroft Institute, Sci-Tech Daresbury, Keckwick Lane, Warrington WA4 4AD (United Kingdom); P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 119991 Leninskiy prospekt 53, Moscow (Russian Federation); Arodzero, A. [Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139 (United States); RadiaBeam Technologies Inc., 1717 Stewart St., Santa Monica, CA 90404 (United States); Lanza, R.C. [Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139 (United States); Welsch, C.P. [University of Liverpool and Cockcroft Institute, Sci-Tech Daresbury, Keckwick Lane, Warrington WA4 4AD (United Kingdom)

    2015-07-01

    Recently Silicon Photomultipliers (SiPMs) have become well recognized as the detector of choice for various applications which demand good photon number resolution and time resolution of short weak light pulses in the nanosecond time scale. In the case of longer and more intensive light pulses, SiPM performance gradually degrades due to dark noise, afterpulsing, and non-instant cell recovering. Nevertheless, SiPM benefits are expected to overbalance their drawbacks in applications such as X-ray cargo inspection using Scintillation-Cherenkov detectors and accelerator beam loss monitoring with Cherenkov fibres, where light pulses of a microsecond time scale have to be detected with good amplitude and timing resolution in a wide dynamic range of 10{sup 5}–10{sup 6}. This report is focused on transient characteristics of a SiPM response on a long rectangular light pulse with special attention to moderate and high light intensities above the linear dynamic range. An analytical model of the transient response and an initial consideration of experimental results in comparison with the model are presented.

  5. Light induced modulation instability of surfaces under intense illumination

    KAUST Repository

    Burlakov, V. M.

    2013-12-17

    We show that a flat surface of a polymer in rubber state illuminated with intense electromagnetic radiation is unstable with respect to periodic modulation. Initial periodic perturbation is amplified due to periodic thermal expansion of the material heated by radiation. Periodic heating is due to focusing-defocusing effects caused by the initial surface modulation. The surface modulation has a period longer than the excitation wavelength and does not require coherent light source. Therefore, it is not related to the well-known laser induced periodic structures on polymer surfaces but may contribute to their formation and to other phenomena of light-matter interaction.

  6. Carcinogenesis related to intense pulsed light and UV exposure

    DEFF Research Database (Denmark)

    Hedelund, L; Lerche, C; Wulf, H C;

    2006-01-01

    This study examines whether intense pulsed light (IPL) treatment has a carcinogenic potential itself or may influence ultraviolet (UV)-induced carcinogenesis. Secondly, it evaluates whether UV exposure may influence IPL-induced side effects. Hairless, lightly pigmented mice (n=144) received three...... observation period. Side effects were evaluated clinically. No tumors appeared in untreated control mice or in just IPL-treated mice. Skin tumors developed in UV-exposed mice independently of IPL treatments. The time it took for 50% of the mice to first develop skin tumor ranged from 47 to 49 weeks...

  7. Sunrise alarm clock for the hearing impaired - biomed 2011.

    Science.gov (United States)

    Follum, James D; Catchpole, Jennifer M

    2011-01-01

    The Sunrise Alarm Clock is a device designed to be more effective than standard alarm clocks and more pleasant than specialty devices in waking the hearing impaired. This is accomplished with the inclusion of visual, physical, and audio alarms. The visual alarm stimulus is created by manipulating the light output of a bedside lamp to mimic the sunrise. This is achieved by varying the duty cycle of a pulse width modulated signal supplied through a standard three-prong receptacle located on the side of the alarm clock. Physical alarms are in the form of wristbands containing vibrating motors. Finally, audio alarms are provided with both volume and pitch control to match the user’s specific needs. The entire system is designed with two users in mind by providing two independently controlled receptacles, wristbands, and audio systems. At the conclusion of development, a nearly fully functional prototype has been produced. The prototype’s audio and physical alarm system along with one visual alarm are fully functional. Shortcomings include poor timekeeping accuracy and problems clearly displaying the time. Even so, this development in sleep technology is capable of performing its task and waking its user with all three alarm systems.

  8. Crystalline silicon cell performance at low light intensities

    Energy Technology Data Exchange (ETDEWEB)

    Reich, N.H.; van Sark, W.G.J.H.M.; Alsema, E.A.; Turkenburg, W.C. [Utrecht University, Faculty of Science, Copernicus Institute for Sustainable Development and Innovation, Department of Science, Techonology and Society, Heidelberglaan 2, 3584 CS Utrecht (Netherlands); Lof, R.W.; Schropp, R.E.I. [Utrecht University, Faculty of Science, Debye Institute for Nanomaterials Science, Nanophotonics - Physics of Device, Utrecht University, P.O. Box 80.000, 3508 TA Utrecht (Netherlands); Sinke, W.C. [Energy research Centre of the Netherlands (ECN), P.O. Box 1, 1755 ZG Petten (Netherlands)

    2009-09-15

    Measured and modelled JV characteristics of crystalline silicon cells below one sun intensity have been investigated. First, the JV characteristics were measured between 3 and 1000 W/m{sup 2} at 6 light levels for 41 industrially produced mono- and multi-crystalline cells from 8 manufacturers, and at 29 intensity levels for a single multi-crystalline silicon between 0.01 and 1000 W/m{sup 2}. Based on this experimental data, the accuracy of the following four modelling approaches was evaluated: (1) empirical fill factor expressions, (2) a purely empirical function, (3) the one-diode model and (4) the two-diode model. Results show that the fill factor expressions and the empirical function fail at low light intensities, but a new empirical equation that gives accurate fits could be derived. The accuracy of both diode models are very high. However, the accuracy depends considerably on the used diode model parameter sets. While comparing different methods to determine diode model parameter sets, the two-diode model is found to be preferred in principle: particularly its capability in accurately modelling V{sub OC} and efficiency with one and the same parameter set makes the two-diode model superior. The simulated energy yields of the 41 commercial cells as a function of irradiance intensity suggest unbiased shunt resistances larger than about 10 k{omega} cm{sup 2} may help to avoid low energy yields of cells used under predominantly low light intensities. Such cells with diode currents not larger than about 10{sup -9} A/cm{sup 2} are excellent candidates for Product Integrated PV (PIPV) appliances. (author)

  9. Effects of light propagation in middle intensity atmospheric turbulence

    Institute of Scientific and Technical Information of China (English)

    Xiubua YUAN; Dexiu HUANG; Bangxu LI

    2009-01-01

    The purpose of this report is to present an experimental study of the effects of light propagation through atmospheric turbulence.Free space optical communication is a line-of-sight technology that transmits a modulated beam of visible light through the atmosphere for broadband communication.The fundamental limitations of free space optical communications arise from the environment through which it propagates.However these systems are vulnerable to atmospheric turbulence, such as attenuation and scintillation, Scintillation is due to the air index variation under the temperature effects.These factors cause an attenuated receiver signal and lead to higher bit error rate (BER).An experiment of laser propagation was carried out to characterize the light intensity through turbulent air in the laboratory environment.The experimental results agree with the calculation based on Rytov for the case of weak to intermediate turbulence.Also, we show the characteristics of irradiance scintillation, intensity distribution and atmospheric turbulence strength.By means of laboratory simulated turbulence, the turbulence box is constructed with the following measurements: 0.5 m wide, 2m long and 0.5m high.The simulation box consists of three electric heaters and is well described for understanding the experimental set up.The fans and heaters are used to increase the homogeneity of turbulence and to create different scintillation indices.The received intensity scintillation and atmosphere turbulence strength were obtained and the variation of refractive index, with its corresponding structure parameter, is calculated from the experimental results.

  10. Multifractal analysis of light scattering-intensity fluctuations

    Science.gov (United States)

    Shayeganfar, F.; Jabbari-Farouji, S.; Movahed, M. Sadegh; Jafari, G. R.; Tabar, M. Reza Rahimi

    2009-12-01

    We provide a simple interpretation of non-Gaussian nature of the light scattering-intensity fluctuations from an aging colloidal suspension of Laponite using the multiplicative cascade model, Markovian method, and volatility correlations. The cascade model and Markovian method enable us to reproduce most of recent empirical findings: long-range volatility correlations and non-Gaussian statistics of intensity fluctuations. We provide evidence that the intensity increments Δx(τ)=I(t+τ)-I(t) , upon different delay time scales τ , can be described as a Markovian process evolving in τ . Thus, the τ dependence of the probability density function p(Δx,τ) on the delay time scale τ can be described by a Fokker-Planck equation. We also demonstrate how drift and diffusion coefficients in the Fokker-Planck equation can be estimated directly from the data.

  11. Fast and effective: intense pulse light photodynamic inactivation of bacteria.

    Science.gov (United States)

    Maisch, Tim; Spannberger, Franz; Regensburger, Johannes; Felgenträger, Ariane; Bäumler, Wolfgang

    2012-07-01

    The goal of this study was to investigate the photodynamic toxicity of TMPyP (5, 10, 15, 20-Tetrakis (1-methylpyridinium-4-yl)-porphyrin tetra p-toluenesulfonate) in combination with short pulses (ms) of an intense pulse light source within 10 s against Bacillus atrophaeus, Staphylococcus aureus, Methicillin-resistant S. aureus and Escherichia coli, major pathogens in food industry and in health care, respectively. Bacteria were incubated with a photoactive dye (TMPyP) that is subsequently irradiated with visible light flashes of 100 ms to induce oxidative damage immediately by generation of reactive oxygen species like singlet oxygen. A photodynamic killing efficacy of up to 6 log(10) (>99.9999%) was achieved within a total treatment time of 10 s using a concentration range of 1-100 μmol TMPyP and multiple light flashes of 100 ms (from 20 J cm(-2) up to 80 J cm(-2)). Both incubation of bacteria with TMPyP alone or application of light flashes only did not have any negative effect on bacteria survival. Here we could demonstrate for the first time that the combination of TMPyP as the respective photosensitizer and a light flash of 100 ms of an intense pulsed light source is enough to generate sufficient amounts of reactive oxygen species to kill these pathogens within a few seconds. Increasing antibiotic resistance requires fast and efficient new approaches to kill bacteria, therefore the photodynamic process seems to be a promising tool for disinfection of horizontal surfaces in industry and clinical purposes where savings in time is a critical point to achieve efficient inactivation of microorganisms.

  12. High-intensity light-emitting diode vs fluorescent tubes for intensive phototherapy in neonates.

    Science.gov (United States)

    Sherbiny, Hanan S; Youssef, Doaa M; Sherbini, Ahmad S; El-Behedy, Rabab; Sherief, Laila M

    2016-05-01

    Special blue fluorescent tubes are recommended by the American Academy of Pediatrics (AAP) as the most effective light source for lowering serum bilirubin. A high-intensity light-emitting diode ('super LED') could render intensive phototherapy more effective than the above conventional methods. This study compared the efficacy and safety of a high-intensity light-emitting diode bed vs conventional intensive phototherapy with triple fluorescent tube units as a rescue treatment for severe unconjugated neonatal hyperbilirubinaemia. This was a randomised, prospective trial. Two hundred jaundiced neonates ≥ 35 weeks gestation who met the criteria for intensive phototherapy as per AAP guidelines were randomly assigned to be treated either with triple fluorescent tube units (group 1, n = 100) or a super LED bed (group 2, n = 100). The outcome was the avoidance of exchange transfusion by successful control of hyperbilirubinaemia. Statistically significant higher success rates of intensive phototherapy were achieved among neonates treated with super LED (group 2) than in those treated conventionally (group 1) (87% vs 64%, P = 0.003). Significantly higher 'bilirubin decline' rates were reported in both haemolytic and non-haemolytic subgroups treated with the super LED bed compared with a similar sub-population in the conventionally treated group. Comparable numbers of neonates in both groups developed rebound jaundice (8% vs 10% of groups 1 and 2, respectively). Side-effects were mild in both groups, but higher rates of hyperthermia (12% vs 0%, P = 0.03), dehydration (8% vs 2%, P = 0.26) and skin rash (39% vs 1%, P = 0.002) were reported in the fluorescent tubes-treated group compared with the LED group. Super LED is a safe rescue treatment for severe neonatal hyperbilirubinaemia, and its implementation may reduce the need for exchange transfusion.

  13. The Sun Radio Imaging Space Experiment (SunRISE) Mission

    Science.gov (United States)

    Lazio, Joseph; Kasper, Justin; Maksimovic, Milan; Alibay, Farah; Amiri, Nikta; Bastian, Tim; Cohen, Christina; Landi, Enrico; Manchester, Ward; Reinard, Alysha; Schwadron, Nathan; Cecconi, Baptiste; Hallinan, Gregg; Hegedus, Alex; Krupar, Vratislav; Zaslavsky, Arnaud

    2017-04-01

    Radio emission from coronal mass ejections (CMEs) is a direct tracer of particle acceleration in the inner heliosphere and potential magnetic connections from the lower solar corona to the larger heliosphere. Energized electrons excite Langmuir waves, which then convert into intense radio emission at the local plasma frequency, with the most intense acceleration thought to occur within 20 RS. The radio emission from CMEs is quite strong such that only a relatively small number of antennas is required to detect and map it, but many aspects of this particle acceleration and transport remain poorly constrained. Ground-based arrays would be quite capable of tracking the radio emission associated with CMEs, but absorption by the Earth's ionosphere limits the frequency coverage of ground-based arrays (ν ≳ 15 MHz), which in turn limits the range of solar distances over which they can track the radio emission (≲ 3RS). The state-of-the-art for tracking such emission from space is defined by single antennas (Wind/WAVES, Stereo/SWAVES), in which the tracking is accomplished by assuming a frequency-to-density mapping; there has been some success in triangulating the emission between the spacecraft, but considerable uncertainties remain. We describe the Sun Radio Imaging Space Experiment (SunRISE) mission concept: A constellation of small spacecraft in a geostationary graveyard orbit designed to localize and track radio emissions in the inner heliosphere. Each spacecraft would carry a receiving system for observations below 25 MHz, and SunRISE would produce the first images of CMEs more than a few solar radii from the Sun. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  14. What Time Is Sunrise? Revisiting the Refraction Component of Sunrise/set Prediction Models

    Science.gov (United States)

    Wilson, Teresa; Bartlett, Jennifer L.; Hilton, James Lindsay

    2017-01-01

    Algorithms that predict sunrise and sunset times currently have an error of one to four minutes at mid-latitudes (0° - 55° N/S) due to limitations in the atmospheric models they incorporate. At higher latitudes, slight changes in refraction can cause significant discrepancies, even including difficulties determining when the Sun appears to rise or set. While different components of refraction are known, how they affect predictions of sunrise/set has not yet been quantified. A better understanding of the contributions from temperature profile, pressure, humidity, and aerosols could significantly improve the standard prediction. We present a sunrise/set calculator that interchanges the refraction component by varying the refraction model. We then compare these predictions with data sets of observed rise/set times to create a better model. Sunrise/set times and meteorological data from multiple locations will be necessary for a thorough investigation of the problem. While there are a few data sets available, we will also begin collecting this data using smartphones as part of a citizen science project. The mobile application for this project will be available in the Google Play store. Data analysis will lead to more complete models that will provide more accurate rise/set times for the benefit of astronomers, navigators, and outdoorsmen everywhere.

  15. Light-intensity and high-intensity interval training improve cardiometabolic health in rats.

    Science.gov (United States)

    Batacan, Romeo B; Duncan, Mitch J; Dalbo, Vincent J; Connolly, Kylie J; Fenning, Andrew S

    2016-09-01

    Physical activity has the potential to reduce cardiometabolic risk factors but evaluation of different intensities of physical activity and the mechanisms behind their health effects still need to be fully established. This study examined the effects of sedentary behaviour, light-intensity training, and high-intensity interval training on biometric indices, glucose and lipid metabolism, inflammatory and oxidative stress markers, and vascular and cardiac function in adult rats. Rats (12 weeks old) were randomly assigned to 1 of 4 groups: control (CTL; no exercise), sedentary (SED; no exercise and housed in small cages to reduce activity), light-intensity trained (LIT; four 30-min exercise bouts/day at 8 m/min separated by 2-h rest period, 5 days/week), and high-intensity interval trained (HIIT, four 2.5-min work bouts/day at 50 m/min separated by 3-min rest periods, 5 days/week). After 12 weeks of intervention, SED had greater visceral fat accumulation (p < 0.01) and slower cardiac conduction (p = 0.04) compared with the CTL group. LIT and HIIT demonstrated beneficial changes in body weight, visceral and epididymal fat weight, glucose regulation, low-density lipoprotein cholesterol, total cholesterol, and mesenteric vessel contractile response compared with the CTL group (p < 0.05). LIT had significant improvements in insulin sensitivity and cardiac conduction compared with the CTL and SED groups whilst HIIT had significant improvements in systolic blood pressure and endothelium-independent vasodilation to aorta and mesenteric artery compared with the CTL group (p < 0.05). LIT and HIIT induce health benefits by improving traditional cardiometabolic risk factors. LIT improves cardiac health while HIIT promotes improvements in vascular health.

  16. SUNRISE WORLD WAR英雄谭

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    SUNRISE WORLD WAR》是一款集合了历代 SUNRISE 作品的 S·RPG 类游戏(下面简称 SWW),今年暑假就会登场与我们见面。相信所有机战游戏迷们对于制作厂商 BANPRESTO 这个名字一定不会陌生吧,本作将继续由其顶头公司 BANDAI 亲自出马制作,游戏来到第三集,在阵容和系统上再现突破。紧张的故事剧情和多部精彩动画中的主人公使游戏更为引人。而且在游戏剧情介绍后还会有全作品登场表,相信这是所有动画和机战迷们不可错过的—项。

  17. Rhodopsin gene expression regulated by the light dark cycle, light spectrum and light intensity in the dinoflagellate Prorocentrum

    OpenAIRE

    Shi, Xinguo; Li, Ling; Guo, Chentao; Lin, Xin; Li, Meizhen; Lin, Senjie

    2015-01-01

    The proton pump rhodopsin is widely found in marine bacteria and archaea, where it functions to capture light energy and convert it to ATP. While found in several lineages of dinoflagellates, this gene has not been studied in Prorocentrales species and whether it functionally tunes to light spectra and intensities as in bacteria remains unclear. Here we identified and characterized this gene in the bloom-forming Prorocentrum donghaiense. It is a 7-helix transmembrane polypeptide containing co...

  18. ELVES light intensity studies at the Pierre Auger Observatory

    Science.gov (United States)

    Mussa, Roberto; Maiorana, Carolina

    2016-04-01

    The Pierre Auger Observatory, located in Malargüe (Argentina), is the largest facility (3000 km2) for the study of Ultra High Energy Cosmic Rays (E>1018 eV). The four sites of the Fluorescence Detector (FD) are continuously observing the night sky with moon fraction below 50% (13% duty cycle) with 100 ns time resolution and a space resolution below one degree. The fluorescence light (λ = 300 nm to 420 nm) produced by shower in the atmosphere is proportional to the energy of the primary cosmic ray. The atmospheric optical properties are continuously monitored by the Observatory with a set of dedicated instruments (lidars, cloud cameras, weather stations). The energy of each cosmic ray can therefore be measured with a systematic energy resolution about 14%. After the serendipitous discovery of an ELVES candidate event in 2005, a special trigger has been implemented to detect these phenomena with high efficiency, fully operational since March 2013. Since January 2014 the ELVES candidates are read out with a modified DAQ scheme, to observe the light emission from above the vertical of the causative lightning. This paper will report about the analysis of the correlation between light emission and lightning intensity as recorded by lightning detection networks, on data taken in the last three years of operation.

  19. Acne treatment by methyl aminolevulinate photodynamic therapy with red light vs. intense pulsed light.

    Science.gov (United States)

    Hong, Jong Soo; Jung, Jae Yoon; Yoon, Ji Young; Suh, Dae Hun

    2013-05-01

    Various methods of photodynamic therapy (PDT) for acne have been introduced. However, comparative studies among them are still needed. We performed this study to compare the effect of methyl aminolevulinate (MAL) PDT for acne between red light and intense pulsed light (IPL). Twenty patients were enrolled in this eight-week, prospective, split-face study. We applied MAL cream over the whole face with a three-hour incubation time. Then patients were irradiated with 22 J/cm(2) of red light on one-half of the face and 8-10 J/cm(2) of IPL on the other half during each treatment session. We performed three treatment sessions at two-week intervals and followed-up patients until four weeks after the last session. Inflammatory and non-inflammatory acne lesions were reduced significantly on both sides. The red light side showed a better response than the IPL side after the first treatment. Serious adverse effects after treatment were not observed. MAL-PDT with red light and IPL are both an effective and safe modality in acne treatment. Red light showed a faster response time than IPL. After multiple sessions, both light sources demonstrated satisfactory results. We suggest that reducing the total dose of red light is desirable when performing MAL-PDT in Asian patients with acne compared with Caucasians.

  20. The sunrise amplitude equation applied to an Egyptian temple

    CERN Document Server

    Sparavigna, Amelia Carolina

    2012-01-01

    An equation, fundamental for solar energy applications, can be used to determine the sunrise amplitude at given latitude. It is therefore suitable for being applied to archaeoastronomical calculations concerning the orientation of towns, worship places and buildings. Here it is discussed the case of the Great Temple of Amarna, Egypt, oriented toward the sunrise on the winter solstice.

  1. Position Detection Based on Intensities of Reflected Infrared Light

    DEFF Research Database (Denmark)

    Christensen, Henrik Vie

    This thesis focuses on development of methods for using infrared sensors for position detection. There exist various methods where optical sensors are used to give position estimates, many utilizing multiple cameras. The overall approach in this thesis is to base a position detection sensor system...... challenge of this work is to reconstruct the object position based on knowledge of the emitted and received signals. Methods for reconstructing the object position has been developed for both 3D space and 2D space. The method for position reconstruction in 3D space is based on a 3D Reflection Map Model....... The 3D Reflection Map Model is developed to model the intensities of light reflected by a spherical object. The 3D object position is reconstructed by searching the parameter space of the 3D Reflection Map Model. The position reconstruction for the 2D space is based on simple calculations on the direct...

  2. The risk of retina damage from high intensity light sources.

    Science.gov (United States)

    Pollak, V A; Romanchuk, K G

    1980-05-01

    The risk of thermal damage to the retina of the eye by exposure to excessive light intensities from continuous and pulsed man-made sources is discussed. The probability of injury increases, the larger the radiant power absorbed by the retina and the smaller the size of the retinal image of the source. A mehtod of estimating the temperature increase of the immediately affected area of the retina is presented. The time constants involved are also briefly considered. Using numerical values from literature for the relevant parameters of the eye, threshold values for a variety of conditions can be established. Below these values little risk of retina damage should exist. The degree of hazard when these values are exceeded depends upon the circumstances. A case study of a welding accident showed good agreement between the conclusions of the theoretical analysis and clinical findings.

  3. Intense pulsed light sintering of copper nanoink for printed electronics

    Science.gov (United States)

    Kim, Hak-Sung; Dhage, Sanjay R.; Shim, Dong-Eun; Hahn, H. Thomas

    2009-12-01

    An intense pulsed light (IPL) from a xenon flash lamp was used to sinter copper nanoink printed on low-temperature polymer substrates at room temperature in ambient condition. The IPL can sinter the copper nanoink without damaging the polymer substrates in extremely short time (2 ms). The microstructure of the sintered copper film was investigated using X-ray powder diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), X-ray micro tomography, and atomic force microscopy (AFM). The sintered copper film has a grainy structure with neck-like junctions. The resulting resistivity was 5 μΩ cm of electrical resistivity which is only 3 times as high as that of bulk copper. The IPL sintering technique allows copper nanoparticles to be used in inkjet printing on low-temperature substrates such as polymers in ambient conditions.

  4. Granulomatous tattoo reaction induced by intense pulse light treatment.

    Science.gov (United States)

    Tourlaki, Athanasia; Boneschi, Vinicio; Tosi, Diego; Pigatto, Paolo; Brambilla, Lucia

    2010-10-01

    Cosmetic tattooing involves implantation of pigments into the dermis in order to create a permanent makeup. Here, we report a case of sarcoidal granulomatous reaction to old cosmetic tattoos after an intense pulsed light (IPL) treatment for facial skin rejuvenation. We consider this case as a peculiar example of photo-induced reaction to tattoo. In addition, we hypothesize that an underlying immune dysfunction was present, and acted as a predisposing factor for this unusual response, as the patient had suffered from an episode of acute pulmonary sarcoidosis 15 years before. Overall, our observation suggests that IPL treatment should be used cautiously in patients with tattoos, especially when a history of autoimmune disease is present.

  5. Intense pulsed light sintering of copper nanoink for printed electronics

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hak-Sung; Dhage, Sanjay R.; Shim, Dong-Eun [University of California, Mechanical and Aerospace Engineering Department, Los Angeles, CA (United States); Hahn, H.T. [University of California, Mechanical and Aerospace Engineering Department, Los Angeles, CA (United States); University of California, Material Science and Engineering Department, California NanoSystems Institute, Los Angeles, CA (United States)

    2009-12-15

    An intense pulsed light (IPL) from a xenon flash lamp was used to sinter copper nanoink printed on low-temperature polymer substrates at room temperature in ambient condition. The IPL can sinter the copper nanoink without damaging the polymer substrates in extremely short time (2 ms). The microstructure of the sintered copper film was investigated using X-ray powder diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), X-ray micro tomography, and atomic force microscopy (AFM). The sintered copper film has a grainy structure with neck-like junctions. The resulting resistivity was 5{mu}{omega} cm of electrical resistivity which is only 3 times as high as that of bulk copper. The IPL sintering technique allows copper nanoparticles to be used in inkjet printing on low-temperature substrates such as polymers in ambient conditions. (orig.)

  6. Rhodopsin gene expression regulated by the light dark cycle, light spectrum and light intensity in the dinoflagellate Prorocentrum.

    Science.gov (United States)

    Shi, Xinguo; Li, Ling; Guo, Chentao; Lin, Xin; Li, Meizhen; Lin, Senjie

    2015-01-01

    The proton pump rhodopsin is widely found in marine bacteria and archaea, where it functions to capture light energy and convert it to ATP. While found in several lineages of dinoflagellates, this gene has not been studied in Prorocentrales species and whether it functionally tunes to light spectra and intensities as in bacteria remains unclear. Here we identified and characterized this gene in the bloom-forming Prorocentrum donghaiense. It is a 7-helix transmembrane polypeptide containing conserved domains and critical amino acid residues of PPR. This gene is phylogenetically affiliated to the xanthorhodopsin clade, but seems to have a distinct evolutionary origin. Quantitative reverse transcription PCR showed that in regular cultures, the transcript abundance of the gene exhibited a clear diel pattern, high abundance in the light period and low in the dark. The same diel pattern was observed for protein abundance with a Western blot using specific antiserum. The rhythm was dampened when the cultures were shifted to continuous dark or light condition, suggesting that this gene is not under circadian clock control. Rhodopsin transcript and protein abundances varied with light intensity, both being highest at a moderate illumination level. Furthermore, the expression of this gene responded to different light spectra, with slightly higher transcript abundance under green than blue light, and lowest abundance under red light. Transformed Escherichia coli over-expressing this rhodopsin gene also exhibited an absorption maximum in the blue-green region with slightly higher absorption in the green. These rhodopsin-promoting light conditions are similar to the relatively turbid marine habitat where the species forms blooms, suggesting that this gene may function to compensate for the light-limited photosynthesis in the dim environment.

  7. Rhodopsin gene expression regulated by the light dark cycle, light spectrum and light intensity in the dinoflagellate Prorocentrum

    Directory of Open Access Journals (Sweden)

    Xinguo eShi

    2015-06-01

    Full Text Available The proton pump rhodopsin (PPR is widely found in marine bacteria and archaea, where it functions to capture light energy and convert it to ATP. While found in several lineages of dinoflagellates, this gene has not been studied in Prorocentrales species and whether it functionally tunes to light spectra and intensities as in bacteria remains unclear. Here we identified and characterized this gene in the bloom-forming Prorocentrum donghaiense. It is a 7-helix transmembrane polypeptide containing conserved domains and critical amino acid residues of PPR. This gene is phylogenetically affiliated to the xanthorhodopsin clade, but seems to have a distinct evolutionary origin. Quantitative reverse transcription PCR (qRT-PCR showed that in regular cultures, the transcript abundance of the gene exhibited a clear diel pattern, high abundance in the light period and low in the dark. The same diel pattern was observed for protein abundance with a Western blot using specific antiserum. The rhythm was dampened when the cultures were shifted to continuous dark or light condition, suggesting that this gene is not under circadian clock control. Rhodopsin transcript and protein abundances varied with light intensity, both being highest at a moderate illumination level. Furthermore, the expression of this gene responded to different light spectra, with slightly higher transcript abundance under green than blue light, and lowest abundance under red light. Transformed E. coli over-expressing this rhodopsin gene also exhibited an absorption maximum in the blue-green region with slightly higher absorption in the green. These rhodopsin-promoting light conditions are similar to the relatively turbid marine habitat where the species forms blooms, suggesting that this gene may function to compensate for the light-limited photosynthesis in the dim environment.

  8. Light-dependent magnetoreception in birds: the effect of intensity of 565-nm green light

    Science.gov (United States)

    Wiltschko, W.; Wiltschko, R.; Munro, U.

    In a previous study, Australian silvereyes tested in autumn under monochromatic 565-nm green light at intensities of 2.1 and 7.5mWm-2 preferred their normal northerly migratory direction, whereas they showed a significantly different tendency towards northwest at 15.0mWm-2. Repeating these experiments in spring with silvereyes migrating southward, we again observed well-oriented tendencies in the migratory direction at 2.1 and 7.5mWm-2. At 15.0mWm-2, however, the birds once more preferred northwesterly directions, i.e. their response under this condition proved to be independent of the migratory direction. This contradicts the interpretation that monochromatic green light of this high intensity leads to a rotation of compass information; instead, it appears to produce sensory input that causes birds to give up their migratory direction in favor of a fixed direction of as yet unknown origin.

  9. Directional migration of cancer cells induced by a blue light intensity gradient.

    Science.gov (United States)

    Lan, Chien-Chih; Lu, Eugene Youjhen; Pan, Huei-Jyuan; Lee, Chau-Hwang

    2015-07-01

    We used a spatial light modulator to project an optical micropattern of 473 nm light with a quartic intensity gradient on a single lung cancer cell. We observed that the intracellular amounts of reactive oxygen species (ROS) of the cancer cells were proportional to the intensity of the blue light, and the blue light intensity gradients could drive directional cell migration. This optically induced directional cell migration was inhibited by a ROS scavenger in the culture medium in a dose-dependent manner. In contrast, the ROS levels in fibroblasts were saturated by the blue light at low intensity and therefore the fibroblasts did not exhibit directional migration in the intensity gradient.

  10. 'In a dark place, we find ourselves': light intensity in critical care units.

    Science.gov (United States)

    Durrington, Hannah J; Clark, Richard; Greer, Ruari; Martial, Franck P; Blaikley, John; Dark, Paul; Lucas, Robert J; Ray, David W

    2017-12-01

    Intensive care units provide specialised care for critically ill patients around the clock. However, intensive care unit patients have disrupted circadian rhythms. Furthermore, disrupted circadian rhythms are associated with worse outcome. As light is the most powerful 're-setter' of circadian rhythm, we measured light intensity on intensive care unit. Light intensity was low compared to daylight during the 'day'; frequent bright light interruptions occurred over 'night'. These findings are predicted to disrupt circadian rhythms and impair entrainment to external time. Bright lighting during daytime and black out masks at night might help maintain biological rhythms in critically ill patients and improve clinical outcomes.

  11. Experimental Effective Intensity of Steady and Flashing Light Emitting Diodes for Aircraft Anti-Collision Lighting

    Science.gov (United States)

    2013-08-01

    Human Factors Division, (ANG-C1). The authors of this paper acknowledge the support of Dr. Yoshi Ohno of the National Institute of Standards and...and analytically ( Ohno & Couzin, 2002) for use with LEDs. In addition, other models have been proposed as alternatives for measuring the effective...intensity of a pulsed light source such as the Allard method (Allard, 1876) and the form-factor method (Schmidt-Clausen, 1968). Ohno and Couzin (2002

  12. Daytime light intensity affects seasonal timing via changes in the nocturnal melatonin levels

    Science.gov (United States)

    Kumar, Vinod; Rani, Sangeeta; Malik, Shalie; Trivedi, Amit K.; Schwabl, Ingrid; Helm, Barbara; Gwinner, Eberhard

    2007-08-01

    Daytime light intensity can affect the photoperiodic regulation of the reproductive cycle in birds. The actual way by which light intensity information is transduced is, however, unknown. We postulate that transduction of the light intensity information is mediated by changes in the pattern of melatonin secretion. This study, therefore, investigated the effects of high and low daytime light intensities on the daily melatonin rhythm of Afro-tropical stonechats ( Saxicola torquata axillaris) in which seasonal changes in daytime light intensity act as a zeitgeber of the circannual rhythms controlling annual reproduction and molt. Stonechats were subjected to light conditions simulated as closely as possible to native conditions near the equator. Photoperiod was held constant at 12.25 h of light and 11.75 h of darkness per day. At intervals of 2.5 to 3.5 weeks, daytime light intensity was changed from bright (12,000 lux at one and 2,000 lux at the other perch) to dim (1,600 lux at one and 250 lux at the other perch) and back to the original bright light. Daily plasma melatonin profiles showed that they were linked with changes in daytime light intensity: Nighttime peak and total nocturnal levels were altered when transitions between light conditions were made, and these changes were significant when light intensity was changed from dim to bright. We suggest that daytime light intensity could affect seasonal timing via changes in melatonin profiles.

  13. Lighting intensity of the soilsurface and restocking of oak groves

    Science.gov (United States)

    Slepykh, Victor; Zubko, Anna; Povolotckaia, Nina

    2016-04-01

    Oak groves of Caucasian Mineral Vody region (CMVR) possess a high ecological and balneological potential which defines the significance of their preservation and reproduction [1]. The role assessment of lighting intensity on renewal of oak groves was carried out on four trial squares (ts) in natural sixty-seven years old forest stand with prevalence of English oak (Quercus robur L.) with unimodal sity (type of the habitat - C1). The illumination was measured at the grass level by the universal measuring instrument of meteoparameters ATT-9508 with an illumination sensor of ATA-1591. The assessment of reforestation was carried out according to the established standards [2]. In the winter of 2005 there was conducted a selecting cutting cabin of the forest stand according to a local method on ts2 with intensity 30%, on ts4 - 50% after which the illumination on the soil surface in relation to illumination of an open place in the summer of 2005 increased from 4.9% to 33.9% on ts2, and from 5.9% to 24.4% on ts4. But by 2014 the illumination decreased till 3.0% on ts2, till 5.4% on ts4 because of an intensive soil grassing down. The control was carried out by ts1 and ts3 on which from 2005 to 2014 the illumination of the soil surface decreased from 4 to 2% as a result of the development of all storeys. As a result due to an intensive soil grassing-down, the total quantity of young oak trees decreased from 2005 to 2014 from 25.6 thousand pcs/ha to 5.9 thousand pcs/ha on ts2; on from 17.3 thousand pcs/ha to 4.0 thousand pcs/ha on ts4. At the same time the total quantity of young oak trees on control squares increased respectively for 1.4% (from 18.8 thousand pcs/ha to 19.1 thousand pcs/ha) on ts1, for 38.7% (from 25.2 thousand pcs/ha to 41.1 thousand pcs/ha). The experiment showed that small young oak trees perishes in the first years of their life from a lack of light and competition from grasland vegetation without providing successful reforestation. Conclusion. So it is

  14. White-throated sparrows calibrate their magnetic compass by polarized light cues during both autumn and spring migration.

    Science.gov (United States)

    Muheim, Rachel; Phillips, John B; Deutschlander, Mark E

    2009-11-01

    The interaction and hierarchy of celestial and magnetic compass cues used by migratory songbirds for orientation has long been the topic of an intense debate. We have previously shown that migratory Savannah sparrows, Passerculus sandwichensis, use polarized light cues near the horizon at sunrise and sunset to recalibrate their magnetic compass. Birds exposed to a +/-90 deg. shifted artificial polarization pattern at sunrise or sunset recalibrated their magnetic compass, but only when given full access to celestial cues, including polarized light cues near the horizon. In the current study, we carried out cue conflict experiments with white-throated sparrows, Zonotrichia albicollis, during both spring and autumn migration in a transition zone between the species' breeding and wintering areas on the south shore of Lake Ontario. We show that white-throated sparrows also recalibrate their magnetic compass by polarized light cues at sunrise and sunset. Sunrise exposure to an artificial polarization pattern shifted relative to the natural magnetic field or exposure to a shift of the magnetic field relative to the natural sky both led to recalibration of the magnetic compass, demonstrating that artificial polarizing filters do not create an anomalous, unnatural orientation response. Our results further indicate that there is no evidence for a difference in compass hierarchy between different phases of migration, confirming previous work showing that polarized light cues near the horizon at sunrise and sunset provide the primary calibration reference both in the beginning and at the end of migration.

  15. The Physiologic Reaction of Cucumber to Low Temperature and Low Light Intensity

    Institute of Scientific and Technical Information of China (English)

    CHEN Qing-jun; ZHANG Fu-man; WANG Yong-jian; Kurata Kenji

    2003-01-01

    The dynamics of chlorophyll content, leaf area and photosynthesis of cucumber seedlings were studied under sole stress of two low temperatures and low light intensity as well as combined stresses of low light intensity and the two low temperatures. The results showed that low light intensity reduced sensitivity of cucumber to low temperature and improved chlorophyll content, leaf area and chlorophyll fluorescence quantum yield. The photosynthesis rate was reduced under low light intensity. The intensity of light played the leading role in growth of cucumber under the low temperature condition, while the low temperature played the leading role under the critical low temperature condition. There were differences in reaction to light and temperature among different varieties. The tolerance to low temperature and low light intensity was not always synergetic for the same cucumber variety.

  16. 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

  17. Morphological Properties of Slender Ca ii H Fibrils Observed by Sunrise II

    Science.gov (United States)

    Gafeira, R.; Lagg, A.; Solanki, S. K.; Jafarzadeh, S.; van Noort, M.; Barthol, P.; Blanco Rodríguez, J.; del Toro Iniesta, J. C.; Gandorfer, A.; Gizon, L.; Hirzberger, J.; Knölker, M.; Orozco Suárez, D.; Riethmüller, T. L.; Schmidt, W.

    2017-03-01

    We use seeing-free high spatial resolution Ca ii H data obtained by the Sunrise observatory to determine properties of slender fibrils in the lower solar chromosphere. In this work we use intensity images taken with the SuFI instrument in the Ca ii H line during the second scientific flight of the Sunrise observatory to identify and track elongated bright structures. After identification, we analyze theses structures to extract their morphological properties. We identify 598 slender Ca ii H fibrils (SCFs) with an average width of around 180 km, length between 500 and 4000 km, average lifetime of ≈400 s, and average curvature of 0.002 arcsec‑1. The maximum lifetime of the SCFs within our time series of 57 minutes is ≈2000 s. We discuss similarities and differences of the SCFs with other small-scale, chromospheric structures such as spicules of type I and II, or Ca ii K fibrils.

  18. Morphological properties of slender Ca II H fibrils observed by SUNRISE II

    CERN Document Server

    Gafeira, R; Solanki, Sami K; Jafarzadeh, Shahin; Van Noort, M; Barthol, P; Rodriguez, J Blanco; Iniesta, J C del Toro; Gandorfer, A; Gizon, L; Hirzberger, J; Knolker, M; Suarez, D Orozco; Riethmüller, T L; Schmidt, W

    2016-01-01

    We use seeing-free high spatial resolution Ca II H data obtained by the SUNRISE observatory to determine properties of slender fibrils in the lower solar chromosphere. In this work we use intensity images taken with the SUFI instrument in the Ca II H line during the second scientific flight of the SUNRISE observatory to identify and track elongated bright structures. After the identification, we analyze theses structures in order to extract their morphological properties. We identify 598 slender Ca II H fibrils (SCFs) with an average width of around 180 km, a length between 500 km and 4000 km, an average lifetime of ~400 s, and an average curvature of 0.002 arcsec^-1. The maximum lifetime of the SCFs within our time series of 57 minutes is ~2000 s. We discuss similarities and differences of the SCFs with other small-scale, chromospheric structures such as spicules of type I and II, or Ca II K fibrils.

  19. Human wavelength discrimination of monochromatic light explained by optimal wavelength decoding of light of unknown intensity.

    Directory of Open Access Journals (Sweden)

    Li Zhaoping

    Full Text Available We show that human ability to discriminate the wavelength of monochromatic light can be understood as maximum likelihood decoding of the cone absorptions, with a signal processing efficiency that is independent of the wavelength. This work is built on the framework of ideal observer analysis of visual discrimination used in many previous works. A distinctive aspect of our work is that we highlight a perceptual confound that observers should confuse a change in input light wavelength with a change in input intensity. Hence a simple ideal observer model which assumes that an observer has a full knowledge of input intensity should over-estimate human ability in discriminating wavelengths of two inputs of unequal intensity. This confound also makes it difficult to consistently measure human ability in wavelength discrimination by asking observers to distinguish two input colors while matching their brightness. We argue that the best experimental method for reliable measurement of discrimination thresholds is the one of Pokorny and Smith, in which observers only need to distinguish two inputs, regardless of whether they differ in hue or brightness. We mathematically formulate wavelength discrimination under this wavelength-intensity confound and show a good agreement between our theoretical prediction and the behavioral data. Our analysis explains why the discrimination threshold varies with the input wavelength, and shows how sensitively the threshold depends on the relative densities of the three types of cones in the retina (and in particular predict discriminations in dichromats. Our mathematical formulation and solution can be applied to general problems of sensory discrimination when there is a perceptual confound from other sensory feature dimensions.

  20. Lectures on configuration space methods for sunrise-type diagrams

    CERN Document Server

    Groote, S

    2003-01-01

    In this lecture series I will give a fundamental insight into configuration space techniques which are of help to calculate a broad class of Feynman diagrams, the sunrise-type diagrams. Applications are shown along with basic concepts and techniques.

  1. Physiological and molecular responses to variation of light intensity in rubber Tree (Hevea brasiliensis Muell. Arg..

    Directory of Open Access Journals (Sweden)

    Li-feng Wang

    Full Text Available Light is one of most important factors to plants because it is necessary for photosynthesis. In this study, physiological and gene expression analyses under different light intensities were performed in the seedlings of rubber tree (Hevea brasiliensis clone GT1. When light intensity increased from 20 to 1000 µmol m(-2 s(-1, there was no effect on the maximal quantum yield of photosystem II (PSII photochemistry (Fv/Fm, indicating that high light intensity did not damage the structure and function of PSII reaction center. However, the effective photochemical quantum yield of PSII (Y(II, photochemical quenching coefficient (qP, electron transfer rate (ETR, and coefficient of photochemical fluorescence quenching assuming interconnected PSII antennae (qL were increased significantly as the light intensity increased, reached a maximum at 200 µmol m(-2 s(-1, but decreased from 400 µmol m(-2 s(-1. These results suggested that the PSII photochemistry showed an optimum performance at 200 µmol m(-2 s(-1 light intensity. The chlorophyll content was increased along with the increase of light intensity when it was no more than 400 µmol m(-2 s(-1. Since increasing light intensity caused significant increase in H2O2 content and decreases in the per unit activity of antioxidant enzymes SOD and POD, but the malondialdehyde (MDA content was preserved at a low level even under high light intensity of 1000 µmol m(-2 s(-1, suggesting that high light irradiation did not induce membrane lipid peroxidation in rubber tree. Moreover, expressions of antioxidant-related genes were significantly up-regulated with the increase of light intensity. They reached the maximum expression at 400 µmol m(-2 s(-1, but decreased at 1000 µmol m(-2 s(-1. In conclusion, rubber tree could endure strong light irradiation via a specific mechanism. Adaptation to high light intensity is a complex process by regulating antioxidant enzymes activities, chloroplast formation, and related

  2. Recording A Sunrise: A Citizen Science Project to Enhance Sunrise/set Prediction Times

    Science.gov (United States)

    Wilson, Teresa; Chizek Frouard, Malynda; Bartlett, Jennifer L.

    2017-01-01

    Smartphones, with their ever increasing capabilities, are becoming quite instrumental for data acquisition in a number of fields. Understanding refraction and how it affects what we see on the horizon is no exception. Current algorithms that predict sunrise and sunset times have an error of one to four minutes at mid-latitudes (0° - 55° N/S) due to limitations in the atmospheric models they incorporate. At higher latitudes, slight changes in refraction can cause significant discrepancies, even including difficulties determining when the Sun appears to rise or set. A thorough investigation of the problem requires a substantial data set of observed rise/set times and corresponding meteorological data from around the world, which is currently lacking. We have developed a mobile application so that this data can be taken using smartphones as part of a citizen science project. The app allows the viewer to submit a video of sunrise/set and attaches geographic location along with meteorological data taken from a local weather station. The project will help increase scientific awareness in the public by allowing members of the community to participate in the data-taking process, and give them a greater awareness of the scientific significance of phenomenon they witness every day. The data from the observations will lead to more complete rise/set models that will provide more accurate times to the benefit of astronomers, navigators, and outdoorsmen. The app will be available on the Google Play Store.

  3. Disruptive effects of light pollution on sleep in free-living birds: Season and/or light intensity-dependent?

    Science.gov (United States)

    Raap, Thomas; Sun, Jiachen; Pinxten, Rianne; Eens, Marcel

    2017-09-01

    Light pollution or artificial light at night (ALAN) is an increasing anthropogenic environmental pollutant posing an important potential threat for wildlife. Evidence of its effects on animal physiology and behaviour is accumulating. However, in order to effectively mitigate light pollution it is important to determine which factors contribute to the severity of effects of ALAN. In this experimental study we explored whether there are seasonal-dependent effects of ALAN on sleep in free-living great tits (Parus major), an important model species. Additionally, we looked at whether light intensity determined the severity of effects of ALAN on sleep. We therefore exposed animals to artificial light inside the nest box (3lx) in December (winter) and February (pre-breeding season). Results from February were compared with the results from a previous study in February, using a lower light intensity (1.6lx). We found little evidence for a season-dependent response. Effects of ALAN hardly differed between high and low light intensity. ALAN disrupted sleep with as main effect a decrease in sleep duration (≈-40min) as animals woke up earlier (≈-24min). However, compared to a natural dark situation sleep onset was delayed by high but not by low light intensity of ALAN. Our study underlines earlier found disruptive effects of ALAN on sleep of free-living animals. While we found no conclusive evidence for seasonal or light intensity-dependent effects of ALAN, additional experimental work using lower light intensities might show such differences. Examining potential management options is crucial in mitigating disruptive effects of light pollution, which will be an important focus for future studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Growth of shredders on leaf litter biofilms: the effect of light intensity

    NARCIS (Netherlands)

    Franken, R.J.M.; Waluto, B.; Peeters, E.T.H.M.; Gardeniers, J.J.P.; Beijer, J.A.J.; Scheffer, M.

    2005-01-01

    1. The effect of light intensity on the decomposition of poplar (Populus nigra) leaves and growth of the shredders, Asellus aquaticus and Gammarus pulex, was studied in a laboratory experiment. The response was studied along a gradient of six light intensities of 0, 5, 23, 54, 97 and 156 ¿mol m -2 s

  5. Forage and seed production of Puero (Pueraria javanica in a Different Light intensity level

    Directory of Open Access Journals (Sweden)

    Fanindi A

    2016-06-01

    Full Text Available Puero (Pueraria javanica is forage that can serve as a cover crop in plantations. The limiting factor for plant growth in the plantation is the light intensity, therefore the influence of light intensity on forage and seed production of Puero needs to be examined. Research was conducted at Kaum Pandak Research station of Indonesian Research Institute for Animal Production Bogor and Laboratory of Agrostology Faculty of Animal Husbandry, Bogor Agricultural University, for 16 months. Four levels of light intensity,i.e 100, 80,60 and 40% were applied, leguminosainous species Puero (Pueraria javanica, was used. The treatments were arangged in Randomized Complete Block Design with 3 replications. Data collected were analyzed by ANOVA and Duncan’s Multiple Range Test. Forage production was evaluated in one year. The forage quality and digestibility (invitro were assessed. Seed production was recorded accumulatively from seasonal seed production during one year. Results show that light intensity affected (P 0.05 quality and digestibility of Puero. The highest forage and seed production of Puero were obtained from full light intensity (100%. and seed production of Puero was affected (P < 0.05 by light intensity. The seed quality of Puero was also affected by light intensity. The best seed quality of Puero was achieved by from 80% light intensity.

  6. Dynamics of triacylglycerol and EPA production in Phaeodactylum tricornutum under nitrogen starvation at different light intensities

    NARCIS (Netherlands)

    Remmers, Ilse M.; Martens, Dirk E.; Wijffels, René H.; Lamers, Packo P.

    2017-01-01

    Lipid production in microalgae is highly dependent on the applied light intensity. However, for the EPA producing model-diatom Phaeodactylum tricornutum, clear consensus on the impact of incident light intensity on lipid productivity is still lacking. This study quantifies the impact of different

  7. The effect of light intensity on growth and development of turkey toms.

    Science.gov (United States)

    Yahav, S; Hurwitz, S; Rozenboim, I

    2000-03-01

    1. The effect of light intensities from 10 to 700 lux on the performance of 5 to 18 week-old turkey males was studied in 2 trials. 2. Body weight of 18 week-old turkeys, in both experiments, was highest under the lowest light intensity This coincided with higher weight gain and lower food intake, which resulted in significantly better food conversion efficiency 3. Light intensity affected heart muscle weight but not weight of breast muscle, abdominal fat or testis as proportions of body weight. 4. The decline in plasma T3 concentration with age differed from other treatments at the low light intensity, which resulted in a significantly higher T3 concentration in turkeys exposed to 10 lux at the age of 10 to 15 weeks. 5. It is concluded that light intensity significantly affects food conversion efficiency in turkey males. This is likely to be related to differential investment of energy expenditure for maintenance.

  8. The Flux of Euglena gracilis Cells Depends on the Gradient of Light Intensity

    Science.gov (United States)

    Ogawa, Takuma; Shoji, Erika; Suematsu, Nobuhiko J.; Nishimori, Hiraku; Izumi, Shunsuke; Awazu, Akinori; Iima, Makoto

    2016-01-01

    We have quantified the photomovement behavior of a suspension of Euglena gracilis representing a behavioral response to a light gradient. Despite recent measurements of phototaxis and photophobicity, the details of macroscopic behavior of cell photomovements under conditions of light intensity gradients, which are critical to understand recent experiments on spatially localized bioconvection patterns, have not been fully understood. In this paper, the flux of cell number density under a light intensity gradient was measured by the following two experiments. In the first experiment, a capillary containing the cell suspension was illuminated with different light intensities in two regions. In the steady state, the differences of the cell numbers in the two regions normalized by the total number were proportional to the light difference, where the light intensity difference ranged from 0.5–2.0 μmol m−2 s−1. The proportional coefficient was positive (i.e., the bright region contained many microorganisms) when the mean light intensity was weak (1.25 μmol m−2 s−1), whereas it was negative when the mean intensity was strong (13.75 μmol m−2 s−1). In the second experiment, a shallow rectangular container of the suspension was illuminated with stepwise light intensities. The cell number density distribution exhibited a single peak at the position where the light intensity was about Ic ≃ 3.8 μmol m−2 s−1. These results suggest that the suspension of E. gracilis responded to the light gradient and that the favorable light intensity was Ic. PMID:28033336

  9. Effects of light intensity on photosynthesis and photoprotective mechanisms in apple under progressive drought

    Institute of Scientific and Technical Information of China (English)

    MA Ping; BAI Tuan-hui; WANG Xiao-qian; MA Feng-wang

    2015-01-01

    The effects of light intensity on photosynthesis and photoprotective mechanisms under progressive drought were studied on apple trees (Malus domestica Borkh.) Fuji. The potted trees were exposed to drought stress for 12 days and different light conditions (100, 60 and 25% sunlight). During the progressive drought, the relative water content (RWC) in leaf declined and was faster in full light than in 60 and 25% sunlight. However, the decrease in the net photosynthetic rate (Pn), stomatal conductance (Gs) and Rubisco activity were slower under 100% sunlight condition than other light conditions. After the 6 days of drought, the maximum PSII quantum yield (Fv/Fm), the capacity of electrons move beyond QA- (1-Vj) and electron move from intersystem to PSI acceptor side (1-VI)/(1-VJ) decreased, with greater decline extent in brighter light. While RWCs were 〉75%, the variations in different light intensities of Gs and Rubisco activity at identical RWC, suggested the direct effects of light. While the little difference in the state of photosynthetic electron transport chain among tested light intensities indicates the results of faster water loss rate of light. Our results also demonstrated that the enhancement the de-epoxidations of xanthophyll cycle, activities of ascorbate peroxidase (APX) and catalase (CAT) were directly regulated by light intensity. While the higher photorespiration rate (Pr) under stronger light condition was mainly caused by faster water loss rate of light.

  10. Effects of light intensity on photosynthesis and photoprotective mechanisms in apple under progressive drought

    Institute of Scientific and Technical Information of China (English)

    MA Ping; BAI Tuan-hui; WANG Xiao-qian; MA Feng-wang

    2015-01-01

    The effects of light intensity on photosynthesis and photoprotective mechanisms under progressive drought were studied on apple trees (Malus domestica Borkh.) Fuji. The potted trees were exposed to drought stress for 12 days and different light conditions (100, 60 and 25%sunlight). During the progressive drought, the relative water content (RWC) in leaf declined and was faster in ful light than in 60 and 25%sunlight. However, the decrease in the net photosynthetic rate (Pn), stomatal conductance (Gs) and Rubisco activity were slower under 100%sunlight condition than other light conditions. After the 6 days of drought, the maximum PSII quantum yield (Fv/Fm), the capacity of electrons move beyond QA−(1–VJ) and electron move from intersystem to PSI acceptor side (1–VI)/(1–VJ) decreased, with greater decline extent in brighter light. While RWCs were>75%, the variations in different light intensities of Gs and Rubisco activity at identical RWC, suggested the direct effects of light. While the little difference in the state of photosynthetic electron transport chain among tested light intensities indicates the results of faster water loss rate of light. Our results also demonstrated that the enhancement the de-epoxidations of xanthophyl cycle, activities of ascorbate peroxidase (APX) and catalase (CAT) were directly regulated by light intensity. While the higher photorespiration rate (Pr) under stronger light condition was mainly caused by faster water loss rate of light.

  11. Effects of crepuscular photoenvironment on light-induced behavior of Daphnia.

    Science.gov (United States)

    Grover, P B; Miller, R J

    1984-11-01

    Phototactic response rates in the aquatic crustacean Daphnia magna were found to increase greatly when cultured under a lighting regime that included simulation of sunset and sunrise. The changes in intensity and color of the crepuscular periods are known to be the primary stimulus for vertical migrations of many planktonic forms, and may have importance to many other animals as well. The value of this type of lighting to investigators of animal behavior and physiology is discussed.

  12. Response Characteristics of Plant Bioelectric Potential to Light Intensity Indoor and Outdoor

    Science.gov (United States)

    Shimbo, Tatsuya; Fujii, Masaki; Sawada, Ayako; Oyabu, Takashi; Kimura, Haruhiko

    Plant is affected by environmental factors. For example, these are temperature, humidity and light intensity. The light intensity affected strongly to the plant. The plant produces glucose and oxygen with photosynthesis. Moreover, light intensity is important to purify the contaminants in the atmosphere. In this study, it was examined whether the plant is affected by temperature, wind grade and soil moisture using bioelectric potential characteristics of the plant. Especially plant bioelectric potential to light intensity change was measured. The measurement was carried out in indoor and outdoor. As for the result, the differences of plant bioelectric potential characteristics in the indoor and outdoor were recognized. At that analysis, the integrated value of plant bioelectric potential for 1 minute (vm1) was adopted. Moreover, a high correlation was indicated between the vm1 and light intensity. The correlation coefficient was R2=0.94. It becomes obvious that the plant is affected strongly by light intensity and the plant can understand the environmental factors like light intensity. The characteristics are found by measuring bioelectric potential of the plant. The environmental sensing can be possible by the use of the plant bioelectric potential.

  13. Effects of light intensity on components and topographical structures of extracellular polysaccharides from the cyanobacteria Nostoc sp.

    Science.gov (United States)

    Ge, Hongmei; Xia, Ling; Zhou, Xuping; Zhang, Delu; Hu, Chunxiang

    2014-02-01

    A study on the effects of light intensity (40 and 80 μE/m(2)/sec) on the components and topographical structures of extracellular polysaccharides (EPS) was carried out in cyanobacteria Nostoc sp.. EPS yield increased with light intensity. However, light intensity did not significantly affect the EPS fractions and monosaccharide composition. Higher light intensity generally resulted in higher protein content of EPS in similar fractions. The topographical structure of EPS, investigated by atomic force microscopy, appeared as spherical lumps, chains and networks. The long chains were observed at higher light intensity. Thus, light intensity affected the yield and nature of EPS.

  14. Photosensitivity control of an isotropic medium through polarization of light pulses with tilted intensity front.

    Science.gov (United States)

    Kazansky, Peter G; Shimotsuma, Yasuhiko; Sakakura, Masaaki; Beresna, Martynas; Gecevičius, Mindaugas; Svirko, Yuri; Akturk, Selcuk; Qiu, Jianrong; Miura, Kiyotaka; Hirao, Kazuyuki

    2011-10-10

    We present the first experimental evidence of anisotropic photosensitivity of an isotropic homogeneous medium under uniform illumination. Our experiments reveal fundamentally new type of light induced anisotropy originated from the hidden asymmetry of pulsed light beam with a finite tilt of intensity front. We anticipate that the observed phenomenon, which enables employing mutual orientation of a light polarization plane and pulse front tilt to control interaction of matter with ultrashort light pulses, will open new opportunities in material processing.

  15. Fifty Cases of Chloasma Treated by Acupuncture plus Intensive Pulse Light Irradiation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: To observe the clinical therapeutic effect of acupuncture plus intensive pulse light irradiation on chloasma. Methods: Ninety-six cases of chloasma were randomly divided into two groups, the control group of 46 cases treated by simple acupuncture and the treatment group of 50 cases treated by acupuncture and intensive pulse light irradiation. Results: The total effective rate was 89.1% and 98.0% in the control group and treatment group respectively, with a significant difference between the two groups (P<0.05). Conclusion: For chloasma, the effect of treatment with acupuncture plus intensive pulse light irradiation is superior to that with simple acupuncture.

  16. The effect of temperature and light intensity on hydrogen production by Rhodobacter capsulatus

    Energy Technology Data Exchange (ETDEWEB)

    Eroglu, Inci [Middle East Technical Univ., Ankara (Turkey). Dept. of Chemical Engineering; Sevinc, Pelin [Middle East Technical Univ., Ankara (Turkey). Dept. of Biotechnology; Guenduez, Ufuk; Yucel, Meral [Middle East Technical Univ., Ankara (Turkey). Dept. of Biological Sciences

    2010-07-01

    Rhodobacter capsulatus is a purple non-sulfur photosynthetic bacterium which can produce hydrogen by photofermentation on acetate and lactate. Hydrogen productivity depends on several parameters such as medium composition, pH, light intensity and temperature. In the present study, the effects of temperature and light intensity on hydrogen production were investigated. The cell growth curve has been fitted to the logistic model and hydrogen productivity was interpreted by Modified Gompertz Equation. The maximum productivity was obtained at 30 C and light intensity of 4000 lux. (orig.)

  17. Effect of the light spectrum of various substrates for inkjet printed conductive structures sintered with intense pulsed light

    Science.gov (United States)

    Weise, Dana; Mitra, Kalyan Yoti; Ueberfuhr, Peter; Baumann, Reinhard R.

    2015-02-01

    In this work, the novel method of intense pulsed light (IPL) sintering of a nanoparticle silver ink is presented. Various patterns are printed with the Inkjet technology on two flexible foils with different light spectra. One is a clear Polyethylenterephthalat [PET] foil and the second is a light brownish Polyimide [PI] foil. The samples are flashed with different parameters regarding to pulse intensity and pulse length. Microscopic images are indicating the impact of the flashing parameters and the different light spectra of the substrates on the sintered structures. Sheet and line resistance are measured and the conductivity is calculated. A high influence of the property of the substrate with respect to light absorption and thermal conductivity on the functionality of printed conductive structures could be presented. With this new method of IPL sintering, highly conductive inkjet printed silver patterns could be manufactured within milliseconds on flexible polymeric foils without damaging the substrate.

  18. Intensity noise and spontaneous emission coupling in superluminescent light sources

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, H.F. (Dept. of Electrical Engineering, Texas A and M Univ., College Station, TX (US))

    1990-01-01

    A simple expression for the noise in the photocurrent generated by the detection of light from an ideal superluminescent source is derived using a quantum amplifier model. The excess noise factor {ital X} is found to be related to the photocurrent {ital I{sub d}}, electronic charge, {ital e}, spontaneous emission coupling factor {ital K}, and full width at half maximum power of the emission spectrum {Delta}{ital v}{sub 1/2} by the expression {ital X} = 0.664 {ital I{sub d}/eK}{Delta}{ital v}{sub 1/2}. Implications of this result for the performance of fiberoptic gyroscopes using superluminescent diode (SLD) light sources and for the design of low-noise SLD's are discussed.

  19. Light intensity distribution of a new type of contact laser scalpel

    Institute of Scientific and Technical Information of China (English)

    Jin Fan; Kun Yang; Chuanqing Zhou; Xinyu Chai; Qiushi Ren

    2008-01-01

    The emergent light distribution of a new type of contact laser scalpel is measured in three different states using a light sensor. The relationship between the angle and the light intensity is analyzed. The results show that the strongest light is emitted from two sides and the front of the scalpel. The light from the front mainly plays a role of cutting. The light from two sides contributes to stanch the wound so as to remain a clear visual field during the surgery. It also helps to increase the cutting efficiency.

  20. Influence of light intensity on growth and physiological characteristics of common sage (Salvia officinalis L.

    Directory of Open Access Journals (Sweden)

    George Zervoudakis

    2012-02-01

    Full Text Available The aim of this work was to investigate the effects of four different light intensities on the growth characteristics, physiological parameters and leaf photosynthetic pigments of Salvia officinalis L. The plant's dry mass, number of the leaves and physiological parameters indicated a strong positive correlation with the light intensity. On the other hand, the plant's height and leaf photosynthetic pigments were increased at low light treated plants. These results suggest that the aromatic herb Salvia officinalis L. is adaptable to different light environments.

  1. The Luminous Intensity Requirements of Vehicle Front Lights for Use in Towns.

    Science.gov (United States)

    Fisher, A J

    1974-01-01

    Previous studies suggest that the use of the dipped headlights on urban traffio routes lit by street lighting is undesirable because of glare, yet it is often contended that present marker lights are not adequately conspicuous. An investigation was therefore carried out, using appraisal techniques, to determine the intensity of vehicle front lights which will be adequately conspicuous without being too bright. It was found that the intensity requirements were largely independent of observer attributes, the luminance of the road surface and its surrounds and the number and movement of the vehicles. However, the results suggest that conspicuity and brightness are different attributes of a light. While both increased with increasing luminous intensity, the observers found that, for a given intensity, a larger source was the more conspicuous but that a smaller caused t he more discomfort. Optimum lighting appears to be a town beam, based on dimming the present dipped headlight, giving a straight ahead intensity of 80 ed. If the light is based on the small diameter marker light this value needs to be doubled to give adequate conspicuity, but then this light will be regarded as too bright in about one observation in twenty.

  2. The effects of season, daylight saving and time of sunrise on serum cortisol in a large population.

    Science.gov (United States)

    Hadlow, Narelle C; Brown, Suzanne; Wardrop, Robert; Henley, David

    2014-03-01

    occur 58 minutes later than non-DST peak. In summary, we found that time of sunrise and time of cortisol collection were the most important factors influencing median cortisol. For each hour later that the sun rose there was an almost 5% increase in median cortisol. There was significant seasonal variability with lowest cortisol noted in summer coinciding with the earliest sunrise time. This is an important finding which is consistent with the understanding that light is the major zeitgeber in entrainment of the human circadian cortisol rhythm. Our data suggest this rhythm is resistant to the arbitrary changes in clock time with daylight saving.

  3. High intensity Discharge lighting; Alumbrado de alta intensidad de descarga

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza E, Ernesto J. [Manufacturera de Reactores, S. A., Mexico, D. F. (Mexico)

    1993-12-31

    This paper gets into contact with some fundamentals in the operation of high discharge intensity lamps. There are useful definitions, as well as the study of the operation of high pressure sodium lamps and of metallic additives operating at less than nominal power. [Espanol] Este trabajo pone al lector en contacto con algunos fundamentos de la operacion de las lamparas de alta intensidad de descarga (HID). Se encuentra con definiciones utiles, asi como el estudio de la operacion de las lamparas de sodio en alta presion y de aditivos metalicos operando a una potencia menor que la nominal.

  4. Microsecond pulse width, intense, light-ion beam accelerator

    Science.gov (United States)

    Rej, D. J.; Bartsch, R. R.; Davis, H. A.; Faehl, R. J.; Greenly, J. B.; Waganaar, W. J.

    1993-10-01

    A relatively long-pulse width (0.1-1 μs) intense ion beam accelerator has been built for materials processing applications. An applied Br, magnetically insulated extraction ion diode with dielectric flashover ion source is installed directly onto the output of a 1.2 MV, 300-kJ Marx generator. The diode is designed with the aid of multidimensional particle-in-cell simulations. Initial operation of the accelerator at 0.4 MV indicates satisfactory performance without the need for additional pulse shaping. The effect of a plasma opening switch on diode behavior is considered.

  5. Intense pulsed light in treatment of nevus spilus: brief report of a clinical trial

    Directory of Open Access Journals (Sweden)

    Amir Houshang Ehsani

    2014-10-01

    Conclusion: Intense pulsed light is seemed an effective and safe treatment for nevus spilus Treatment; however randomized control trials with longer follow-up periods are required to evaluate the efficacy and safety.

  6. Novel method for correcting light intensity fluctuation in the TDLAS system

    Institute of Scientific and Technical Information of China (English)

    Guojie Tu; Yu Wang; Fengzhong Dong; Hua Xia; Tao Pang; Zhirong Zhang; Bian Wu

    2012-01-01

    A novel method for online correction of light intensity fluctuation in a practical tunable diode laser absorption spectroscopy (TDLAS) system with wavelength modulation is presented.The proposed method is developed according to the linear relation between peaks at multiple frequencies of sine modulation in the power spectral density of the demodulated second-harmonic (2f) signal and the incident light intensity.Those peaks are demonstrated experimentally and explained as residual power at the first-harmonic and third-harmonic frequencies after 2f demodulation of the residual amplitude modulation signal due to the limited integrating time constant of the lock-in-amplifier.This method can achieve real-time correction of light intensity fluctuations with only little calculation.It can work well in a very large range of light intensity and has great potential applications in the wavelength modulation spectroscopy system.

  7. Light Intensity Affects Pungency of Hot Pepper (Capsicum annuum L.) Fruits

    Institute of Scientific and Technical Information of China (English)

    LV Chang-shan; WANG Jin-ling; YU Guang-jian

    2005-01-01

    This study was carried out both laboratory and field experiment to research the effects of three different light intensity on capsaicin content of hot pepper fruits during the growing stage, the varieties in the study were in different hot levels named No.4 Xiangyan (mid-hot) and No.3 Jingjianjiao (very hot). The study showed that capsaicin content increased accompanied with light intensity weakening. There was an inverse relationship between capsaicin content and peroxidase activity.

  8. Detecting quantum coherence of Bose gases in optical lattices by scattering light intensity in cavity.

    Science.gov (United States)

    Zhou, Xiaoji; Xu, Xu; Yin, Lan; Liu, W M; Chen, Xuzong

    2010-07-19

    We propose a new method of detecting quantum coherence of a Bose gas trapped in a one-dimensional optical lattice by measuring the light intensity from Raman scattering in cavity. After pump and displacement process, the intensity or amplitude of scattering light is different for different quantum states of a Bose gas, such as superfluid and Mott-Insulator states. This method can also be useful to detect quantum states of atoms with two components in an optical lattice.

  9. Modeling spatiotemporal patterns of understory light intensity using airborne laser scanner (LiDAR)

    Science.gov (United States)

    Peng, Shouzhang; Zhao, Chuanyan; Xu, Zhonglin

    2014-11-01

    This study described a spatiotemporally explicit 3D raytrace model to provide spatiotemporal patterns of understory light (light intensity in the forest floor and along the vertical gradient). The model was built based on voxels derived from LiDAR and field investigation data, geographical information (elevation and location), and solar position (azimuth and altitude angles). We calculated the distance (L, in meters) traveled by solar ray in the crowns based on the model, and then calibrated and verified the light attenuation function using L based on Beer's law. L and the ratio of below canopy light intensity to above canopy light intensity showed obviously exponential relationship, with R2 = 0.94 and P competition, soil evaporation, plant transpiration, and snowmelt in the forest.

  10. Particle acceleration studies with intense lasers and advanced light sources

    Science.gov (United States)

    Murphy, C. D.; Gray, R. J.; MacLellan, D. A.; Rusby, D.; McKenna, P.; Ridgers, C. P.; Booth, N.; Robinson, A. P. L.; Wilson, L.; Green, J. S.

    2013-10-01

    The interaction of lasers with matter is a subject which has progressed rapidly over the last two decades as higher intensity lasers are found to have possible applications in inertial fusion, laboratory astrophysics and ion acceleration for oncology or ultrafast proton probing. All of these applications require a good understanding of laser-electron coupling and fast electron transport in solid targets which has proven difficult to diagnose. Here we present data from an experiment carried out on the Astra Gemini laser system at STFC-Rutherford Appleton Laboratory, where novel targets and diagnostics illuminate the complex processes at play. An outline of how x-ray free electron lasers may further expand our understanding of such processes will also be described.

  11. The velocity of light intensity increase modulates the photoprotective response in coastal diatoms.

    Directory of Open Access Journals (Sweden)

    Vasco Giovagnetti

    Full Text Available In aquatic ecosystems, the superimposition of mixing events to the light diel cycle exposes phytoplankton to changes in the velocity of light intensity increase, from diurnal variations to faster mixing-related ones. This is particularly true in coastal waters, where diatoms are dominant. This study aims to investigate if coastal diatoms differently activate the photoprotective responses, xanthophyll cycle (XC and non-photochemical fluorescence quenching (NPQ, to cope with predictable light diel cycle and unpredictable mixing-related light variations. We compared the effect of two fast light intensity increases (simulating mixing events with that of a slower increase (corresponding to the light diel cycle on the modulation of XC and NPQ in the planktonic coastal diatom Pseudo-nitzschia multistriata. During each light treatment, the photon flux density (PFD progressively increased from darkness to five peaks, ranging from 100 to 650 µmol photons m-2 s-1. Our results show that the diel cycle-related PFD increase strongly activates XC through the enhancement of the carotenoid biosynthesis and induces a moderate and gradual NPQ formation over the light gradient. In contrast, during mixing-related PFD increases, XC is less activated, while higher NPQ rapidly develops at moderate PFD. We observe that together with the light intensity and its increase velocity, the saturation light for photosynthesis (Ek is a key parameter in modulating photoprotection. We propose that the capacity to adequately regulate and actuate alternative photoprotective 'safety valves' in response to changing velocity of light intensity increase further enhances the photophysiological flexibility of diatoms. This might be an evolutionary outcome of diatom adaptation to turbulent marine ecosystems characterized by unpredictable mixing-related light changes over the light diel cycle.

  12. Intense pulsed light treatment of hirsutism: case reports of skin phototypes V and VI.

    Science.gov (United States)

    Johnson, F; Dovale, M

    1999-12-01

    Removal of unwanted hair is a common cosmetic concern. For hirsute women, treatment often requires drug therapy and various methods to physically remove the hair. Traditional methods of hair removal include shaving, waxing, tweezing, depilatory creams and electrolysis. Hair removal methods based on light technology, such as lasers and intense pulsed light systems, are alternative methods for longer-term hair removal. Intense pulsed light has been used in our clinic during the past 2 years to treat light-to-dark skinned patients, including skin types V and VI. We present here the treatment, using an intense pulsed light source, of three dark skinned patients with hirsutism. Patients were treated during multiple sessions (five to seven) for unwanted facial hair. Sessions were conducted monthly and patients were evaluated at follow-up sessions 2-7 months after the final treatment. Successful clearance of unwanted hair was achieved in all three patients with no pigmentary changes observed during the final follow-up sessions. Folliculitis and hyperpigmentation from tweezing were also treated by the intense pulsed light source. These results suggest that intense pulsed light is an effective source for hair removal and may, with proper parameter selection, be useful in the treatment of very dark skin types.

  13. Relationships Between the Distribution of Relative Canopy Light Intensity and the Peach Yield and Quality

    Institute of Scientific and Technical Information of China (English)

    HE Feng-li; WANG Fei; WEI Qin-ping; WANG Xiao-wei; ZHANG Qiang

    2008-01-01

    The aim of the present experiment was to study the relationship between the distribution of relative light intensity in canopy and yield and quality of Wanmi peach.The optimum relative canopy light intensity was judged to be 36.3% for high quality peaches,when canopy volumes of Wanmi peach trees with a relative light intensity<30%accounted for 7.7 and 47.9%of the total canopy volume in June and September,respectively.The canopy volume with a relative light intensity>80%was 27.7 and 3.1%of the total canopy volume in June and September.respectively.Peach canopies were divided into 0.5m×0.5m×0.5m cubes.with the relative light intensity being measured at different positions of the canopy during the growing season.Yield and fruit quality were also measured at these positions at harvest.The results showed that the relative light intensity decreased gradually from outside to inside and from top to bottom of the tree canopy.Fruit were mainly distributed in the upper and middle portions of the canopy,1.5-3.0m above ground. Regression results showed that single fruit weight and soluble solid content were positively related to relative light intensity.

  14. High light intensity mediates a shift from allochthonous to autochthonous carbon use in phototrophic stream biofilms

    Science.gov (United States)

    Wagner, Karoline; Bengtsson, Mia M.; Findlay, Robert H.; Battin, Tom J.; Ulseth, Amber J.

    2017-07-01

    Changes in the riparian vegetation along stream channels, diurnal light availability, and longitudinal fluctuations in the local light regime in streams influence primary production and carbon (C) cycling in benthic stream biofilms. To investigate the influence of light availability on the uptake dynamics of autochthonous and allochthonous dissolved organic carbon (DOC) in benthic biofilms, we experimentally added 13C-labeled allochthonous DOC to biofilms grown under light intensities ranging from 5 to 152 μmol photons m-2 s-1. We calculated the net C flux, which showed that benthic biofilms released autochthonous DOC across the entire light gradient. Light availability and diurnal light patterns influenced C uptake by benthic biofilms. More allochthonous DOC was respired under low light availability and at night, whereas under high light availability and during the day mainly autochthonous C was respired by the benthic biofilm community. Furthermore, phenol oxidase activity (indicative of allochthonous DOC uptake) was more elevated under low light availability, whereas beta-glucosidase activity (indicative of autochthonous DOC use) increased with light intensity. Collectively, our results suggest that biofilms exposed to high light inputs preferentially used autochthonous DOC, whereas biofilms incubated at attenuated levels showed greater use of allochthonous DOC. This has implications for the spatial dynamics of DOC uptake in streams and speaks against the occurrence of priming effects in algal-dominated stream biofilms.

  15. Seed vigor, antioxidant metabolism and initial growth characteristics of red rice seedlings under different light intensities

    Directory of Open Access Journals (Sweden)

    Tiago Zanatta Aumonde

    2013-06-01

    Full Text Available This work aimed to evaluate the effect that different intensities of light have on the physiological attributes of red rice seeds and seedlings. Before and after emergence, seedlings were exposed to light levels of 35%; 65% and 100% in a greenhouse. We evaluated shoots and roots, in terms of length and dry mass, as well as leaf area and content of chlorophyll (a,b and total. In leaves and roots, we quantified the activity of superoxide dismutase (SOD, ascorbate peroxidase (APX, catalase (CAT and guaiacol peroxidase (POX. We determined the leaf area ratio (F A, leaf mass ratio (F W, specific leaf area (S A, and shoot/root ratio (P W. At higher light intensities, shoot length decreased, whereas root length, dry mass and number of tillers increased. Leaf area was greatest in seedlings exposed to a 65% light level. The F A, F W, S A and P W were lowest at a light intensity of 100%. Differences in light intensity had qualitative and quantitative effects on chlorophyll contents. The activity of SOD and CAT was higher at lower light levels, whereas the inverse was true for APX and POX activity. Extremes of light availability alter the activity of antioxidant enzymes, negatively affecting the initial growth characteristics and photosynthetic pigments of red rice seedlings.

  16. Responses of fen plant species to groundwater level and light intensity

    NARCIS (Netherlands)

    Kotowski, W; van Andel, J; van Diggelen, R; Hogendorf, J.

    Characteristic species of sedge-moss fen communities occur in constantly wet, nutrient-poor sites with a high penetration of light through the vegetation canopy. We studied the effects of water table depth and differences in light intensity on the performance of fen species. Three fen species (Carex

  17. The application of (RCA 1P 28)-photomultiplier tubes to the detection of weak light intensities

    NARCIS (Netherlands)

    Boeschoten, F.; Milatz, J.M.W.; Smit, C.

    1954-01-01

    Two methods are discussed of measuring weak light intensities (varying but slowly with time) with the aid of a photomultiplier tube. 1°. the light-chopping method in combination with a phase- and frequency-sensitive measuring device (i.c. alternating current galvanometer 1) 2) 3) 4) 16). 2°. the c

  18. Light Intensity is Important for Hydrogen Production in NaHSO3-Treated Chlamydomonas reinhardtii.

    Science.gov (United States)

    Wei, Lanzhen; Yi, Jing; Wang, Lianjun; Huang, Tingting; Gao, Fudan; Wang, Quanxi; Ma, Weimin

    2017-03-01

    Chlamydomonas reinhardtii is a unicellular green alga that can use light energy to produce H2 from H2O in the background of NaHSO3 treatment. However, the role of light intensity in such H2 production remains elusive. Here, light intensity significantly affected the yield of H2 production in NaHSO3-treated C. reinhardtii, which was consistent with its effects on the content of O2 and the expression and activity of hydrogenase. Further, NaHSO3 was found to be able to remove O2 via a reaction of bisulfite with superoxide anion produced at the acceptor side of PSI, and light intensity affected the reaction rate significantly. Accordingly, high light and strong light but not low light can create an anaerobic environment, which is important to activate hydrogenase and produce H2. Based on the above results, we conclude that light intensity plays an important role in removing O2 and consequently activating hydrogenase and producing H2 in NaHSO3-treated C. reinhardtii. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  19. Effect of light intensity and irradiation time on the polymerization process of a dental composite resin

    Directory of Open Access Journals (Sweden)

    Discacciati José Augusto César

    2004-01-01

    Full Text Available Polymerization shrinkage is a critical factor affecting the longevity and acceptability of dental composite resins. The aim of this work was to evaluate the effect of light intensity and irradiation time on the polymerization process of a photo cured dental composite resin by measuring the Vickers hardness number (VHN and the volumetric polymerization shrinkage. Samples were prepared using a dental manual light-curing unit. The samples were submitted to irradiation times of 5, 10, 20 and 40 s, using 200 and 400 mW.cm-2 light intensities. Vickers hardness number was obtained at four different moments after photoactivation (immediate, 1 h, 24 h and 168 h. After this, volumetric polymerization shrinkage values were obtained through a specific density method. The values were analyzed by ANOVA and Duncan's (p = 0.05. Results showed increase in hardness values from the immediate reading to 1 h and 24 h readings. After 24 h no changes were observed regardless the light intensities or activation times. The hardness values were always smaller for the 200 mW.cm-2 light intensity, except for the 40 s irradiation time. No significant differences were detected in volumetric polymerization shrinkage considering the light intensity (p = 0.539 and the activation time (p = 0.637 factors. In conclusion the polymerization of the material does not terminate immediately after photoactivation and the increase of irradiation time can compensate a lower light intensity. Different combinations between light intensity and irradiation time, i.e., different amounts of energy given to the system, have not affected the polymerization shrinkage.

  20. Light-dependent magnetoreception in birds: increasing intensity of monochromatic light changes the nature of the response

    Directory of Open Access Journals (Sweden)

    Bischof Hans-Joachim

    2007-02-01

    Full Text Available Abstract Background The Radical Pair model proposes that magnetoreception is a light-dependent process. Under low monochromatic light from the short-wavelength part of the visual spectrum, migratory birds show orientation in their migratory direction. Under monochromatic light of higher intensity, however, they showed unusual preferences for other directions or axial preferences. To determine whether or not these responses are still controlled by the respective light regimes, European robins, Erithacus rubecula, were tested under UV, Blue, Turquoise and Green light at increasing intensities, with orientation in migratory direction serving as a criterion whether or not magnetoreception works in the normal way. Results The birds were well oriented in their seasonally appropriate migratory direction under 424 nm Blue, 502 nm Turquoise and 565 nm Green light of low intensity with a quantal flux of 8·1015 quanta s-1 m-2, indicating unimpaired magnetoreception. Under 373 nm UV of the same quantal flux, they were not oriented in migratory direction, showing a preference for the east-west axis instead, but they were well oriented in migratory direction under UV of lower intensity. Intensities of above 36·1015 quanta s-1 m-2 of Blue, Turquoise and Green light elicited a variety of responses: disorientation, headings along the east-west axis, headings along the north-south axis or 'fixed' direction tendencies. These responses changed as the intensity was increased from 36·1015 quanta s-1 m-2 to 54 and 72·1015 quanta s-1 m-2. Conclusion The specific manifestation of responses in directions other than the migratory direction clearly depends on the ambient light regime. This implies that even when the mechanisms normally providing magnetic compass information seem disrupted, processes that are activated by light still control the behavior. It suggests complex interactions between different types of receptors, magnetic and visual. The nature of the

  1. The role of lasers and intense pulsed light technology in dermatology

    Science.gov (United States)

    Husain, Zain; Alster, Tina S

    2016-01-01

    The role of light-based technologies in dermatology has expanded dramatically in recent years. Lasers and intense pulsed light have been used to safely and effectively treat a diverse array of cutaneous conditions, including vascular and pigmented lesions, tattoos, scars, and undesired hair, while also providing extensive therapeutic options for cosmetic rejuvenation and other dermatologic conditions. Dermatologic laser procedures are becoming increasingly popular worldwide, and demand for them has fueled new innovations and clinical applications. These systems continue to evolve and provide enhanced therapeutic outcomes with improved safety profiles. This review highlights the important roles and varied clinical applications that lasers and intense pulsed light play in the dermatologic practice. PMID:26893574

  2. Accelerometer-assessed light-intensity physical activity and mortality among those with mobility limitations.

    Science.gov (United States)

    Frith, Emily; Loprinzi, Paul D

    2017-08-31

    Emerging research demonstrates that light-intensity physical activity is favorably associated with numerous health outcomes among the general population, even independent of high-intensity physical activity. To examine the association between accelerometer-assessed light-intensity physical activity and mortality in a national sample of American adults with mobility limitations. Data from the 2003-2006 National Health and Nutrition Examination Survey were utilized. Participants were followed through 2011. Based on self-report, analyzed participants included those with mobility limitations (N = 1369). Light-intensity physical activity was assessed via waist-mounted accelerometry. For the sample, 108,010 person-months occurred with an all-cause mortality rate of 2.07 per 1000 person-months. After adjustments, for every 60 min/day increase in light-intensity physical activity, participants with mobility limitations had a 14% reduced risk of all-cause mortality (HR = 0.86; 95% CI: 0.75-0.98; P = 0.03). These findings underscore the importance of promoting light-intensity physical activity to those with mobility limitations. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Marginal eyespots on butterfly wings deflect bird attacks under low light intensities with UV wavelengths.

    Directory of Open Access Journals (Sweden)

    Martin Olofsson

    Full Text Available BACKGROUND: Predators preferentially attack vital body parts to avoid prey escape. Consequently, prey adaptations that make predators attack less crucial body parts are expected to evolve. Marginal eyespots on butterfly wings have long been thought to have this deflective, but hitherto undemonstrated function. METHODOLOGY/PRINCIPAL FINDINGS: Here we report that a butterfly, Lopinga achine, with broad-spectrum reflective white scales in its marginal eyespot pupils deceives a generalist avian predator, the blue tit, to attack the marginal eyespots, but only under particular conditions-in our experiments, low light intensities with a prominent UV component. Under high light intensity conditions with a similar UV component, and at low light intensities without UV, blue tits directed attacks towards the butterfly head. CONCLUSIONS/SIGNIFICANCE: In nature, birds typically forage intensively at early dawn, when the light environment shifts to shorter wavelengths, and the contrast between the eyespot pupils and the background increases. Among butterflies, deflecting attacks is likely to be particularly important at dawn when low ambient temperatures make escape by flight impossible, and when insectivorous birds typically initiate another day's search for food. Our finding that the deflective function of eyespots is highly dependent on the ambient light environment helps explain why previous attempts have provided little support for the deflective role of marginal eyespots, and we hypothesize that the mechanism that we have discovered in our experiments in a laboratory setting may function also in nature when birds forage on resting butterflies under low light intensities.

  4. The role of lasers and intense pulsed light technology in dermatology

    Directory of Open Access Journals (Sweden)

    Husain Z

    2016-02-01

    Full Text Available Zain Husain,1 Tina S Alster1,2 1Department of Dermatology, Georgetown University Hospital, 2Washington Institute of Dermatologic Laser Surgery, Washington, DC, USA Abstract: The role of light-based technologies in dermatology has expanded dramatically in recent years. Lasers and intense pulsed light have been used to safely and effectively treat a diverse array of cutaneous conditions, including vascular and pigmented lesions, tattoos, scars, and undesired hair, while also providing extensive therapeutic options for cosmetic rejuvenation and other dermatologic conditions. Dermatologic laser procedures are becoming increasingly popular worldwide, and demand for them has fueled new innovations and clinical applications. These systems continue to evolve and provide enhanced therapeutic outcomes with improved safety profiles. This review highlights the important roles and varied clinical applications that lasers and intense pulsed light play in the dermatologic practice. Keywords: laser, intense pulsed light, treatment, dermatology, technology

  5. Growth and biopigment accumulation of cyanobacterium Spirulina platensis at different light intensities and temperature

    Science.gov (United States)

    Kumar, Manoj; Kulshreshtha, Jyoti; Singh, Gajendra Pal

    2011-01-01

    In order to find out optimum culture condition for algal growth, the effect of light irradiance and temperature on growth rate, biomass composition and pigment production of Spirulina platensis were studied in axenic batch cultures. Growth kinetics of cultures showed a wide range of temperature tolerance from 20 °C to 40 °C. Maximum growth rate, cell production with maximum accumulation of chlorophyll and phycobilliproteins were found at temperature 35 °C and 2,000 lux light intensity. But with further increase in temperature and light intensity, reduction in growth rate was observed. Carotenoid content was found maximum at 3,500 lux. Improvement in the carotenoid content with increase in light intensity is an adaptive mechanism of cyanobacterium S.platensis for photoprotection, could be a good basis for the exploitation of microalgae as a source of biopigments. PMID:24031731

  6. Effect of different light intensities on performance, welfare and behavior of turkey poults

    Directory of Open Access Journals (Sweden)

    Hesham Mohammed

    2016-03-01

    Full Text Available Objective: Lighting requirements of birds have to be considered for choosing the optimal light intensity. Therefore, the experiment was carried out to study the effects of the different light intensities on performance, welfare and behavior of turkey poults. Materials and Methods: A total of 81 turkey poults aging 3 weeks were randomly selected and divided into three equal groups. The birds were subjected for 3 different light intensities (5, 25 and 50 lux with 12 h photoperiod in 3 separate rooms. The growth performance parameters of the poults were measured; the parameters were body weight (BW, average feed intake (FI, average body weight gain (ABWG, relative growth rate (RGR, and feed conversion ratio (FCR. Besides, blood parameters and behavioral characters were observed. Results: Our results revealed that poults reared in low intensity (5 lux had better performance (body weight gain, relative growth rate and feed intake. Also, final body weight was significantly higher in 5 lux. The cortisol level was lower in 5 lux than other 25 and 50 lux. Behavior of poults is affected by light intensities in our study, where feather preening, feather pecking and aggressive behaviors were significantly higher in birds housed in the highest intensity (50 lux. In the same way, drinking time was significantly higher in 25 lux. The poults tended to lay and rest on perches more under the lowest intensity (5 lux. Conclusion: It was concluded that, it is better to use moderate light intensity to improve previous parameters with avoiding abnormal behavior. [J Adv Vet Anim Res 2016; 3(1.000: 18-23

  7. Controlling the intensity of light in large areas at the interfaces of a scattering medium

    CERN Document Server

    Ojambati, Oluwafemi S; Gorter, Klaas-Jan; Mosk, Allard P; Vos, Willem L

    2016-01-01

    The recent advent of wave-shaping methods has demonstrated the focusing of light through and inside even the most strongly scattering materials. Typically in wavefront shaping, light is focused in an area with the size of one speckle spot. It has been shown that the intensity is not only increased in the target speckle spot, but also in an area outside the optimized speckle spot. Consequently, the total transmission is enhanced, even though only the intensity in a single speckle spot is controlled. Here, we experimentally study how the intensity enhancement on both interfaces of a scattering medium depends on the optimization area on the transmission side. We observe that as the optimization radius increases, the enhancement of the total transmitted intensity increases. We find a concomitant decrease of the total reflected intensity, which implies an energy redistribution between transmission and reflection channels. In addition, we find a qualitative evidence of a long-range reflection-transmission correlati...

  8. Red rainbows at sunset/sunrise

    Science.gov (United States)

    Ricard, J. L.

    2016-12-01

    The rainbow model deveeloped at CEPAL is based on the Airy theory. The outputs show that a pure red rainbow could only observed from a hill or a mountain when the sun is below the horizon. When the sun is on the horizon, there should be a juxtaposition of a red band on the outside and of a yellow band on the inside (upper figures). However, observers report pure red bows at sea level (lower left figure). In these rare cases, it is possible to still see the sun after it has set. As sunlight passes through more and more dense atmosphere at sunset the light slows and bends closer and closer toward the normal. When the eye traces the light ray it appears to be higher in the sky (lower right figure).

  9. Changes in manganese superoxide dismutase expression after exposure of the retina to intense light.

    Science.gov (United States)

    Yamamoto, M; Lidia, K; Gong, H; Onitsuka, S; Kotani, T; Ohira, A

    1999-02-01

    Manganese superoxide dismutase (Mn-SOD) is a naturally-occurring scavenger of superoxide, one of several reactive oxygen intermediates. To determine if Mn-SOD expression is enhanced as a defensive mechanism against oxidative challenges, such as intense light exposure, rats were exposed to cyclic light (80 lux) for 2 weeks, intense light (1,800 lux) for 24 h, and then again to cyclic light. Experimental and control (exposed to cyclic light only) eyes were enucleated 3 h, 1, 3, 7, and 14 days after light challenge. Protein expression was examined immunohistochemically using rabbit antisera against rat Mn-SOD. There was no significant difference between the light-exposed and the control groups in the thickness of the outer nuclear layers. Both retinal pigment epithelial cells and photoreceptor inner segments in the normal retina were labeled for Mn-SOD. Mn-SOD labeling was lost 3 h and day 1 after light challenge. It was re-expressed in the retinal pigment epithelial cells 3, 7, and 14 days after the light challenge, and in the photoreceptor inner segments after day 14. These results suggest that the retina might have a protective potential against light damage, in which Mn-SOD may play an important role.

  10. Photoprotective and antioxidant responses to light spectrum and intensity variations in the coastal diatom Skeletonema marinoi.

    Science.gov (United States)

    Smerilli, Arianna; Orefice, Ida; Corato, Federico; Gavalás Olea, Antonio; Ruban, Alexander V; Brunet, Christophe

    2017-02-01

    Photosynthesis is known to produce reactive oxygen species together with the transformation of light into biochemical energy. To fill the gap of the knowledge on the protective antioxidant network of microalgae, a series of experiments to explore the role of spectral composition and intensity of light in the modulation of the photodefence mechanisms developed by the coastal diatom Skeletonema marinoi were performed. The modulation of the total phenolic content, ascorbic acid and the enzymes glutathione reductase, catalase, ascorbate peroxidase and superoxide dismutase together with xanthophyll cycle and non-photochemical quenching in response to variations in the light environment were analysed. Most of the enzymes' activity was promptly affected by the red light. Yet, the monochromatic high intensity blue light enhanced the synthesis of total phenolic content and ascorbic acid in parallel to the xanthophyll cycle activity. This study reveals the dual effects of spectral composition and intensity of light on the modulation of photoprotective mechanisms. Diatoms developed a complementary and/or alternative tuning processes to cope with the variable light environment they experience in the water column. They also provided valuable insights into light manipulation regimes for diatom cultivation that will help to maximize production of bioactive molecules. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  11. Light colour and intensity alters reproductive/seasonal responses in Japanese quail.

    Science.gov (United States)

    Yadav, Suneeta; Chaturvedi, Chandra Mohini

    2015-08-01

    An extensive literature is available on the photoperiodic responses of avian species but studies on light colour and wavelength from light emitting diode (LED) sources on reproduction are limited. Hence, an experiment was designed to study the effect of different colours and intensities of light on the reproductive responses of Japanese quail. Three-week old quail were exposed to five different light conditions with a long photoperiod (LD 16:8): WT (white fluorescent light 100 lux as control), W LED (white light emitting diode, 30 lux), B LED (blue LED, 30 lux), G LED (green LED, 30 lux) and R-LED (red LED, 30 lux). The cloacal gland size, an indicator of androgenic activity, was monitored weekly. The results indicated an early initiation of gonadal growth in WT quail which continued and maintained a plateau throughout the period of study. On the other hand, in general low intensity light, there was a decreased amplitude of the reproductive cycle and the quail exposed to different colour lights (green, red and blue lights) used different incubation times to initiate their gonadal growth and exhibited a gonadal cycle of a different duration up to 15.5 weeks. Thereafter, the gonad of quail of all the LED groups started developing again (including the blue LED exposed quail which remained undeveloped until this age) and attained the increased degree of growth until 26.5 weeks of age. During the second cycle, gonads of green and red light exposed quail continued to increase and maintained a plateau of development similar to WT exposed control while white and blue LED exposed quail exhibited spontaneous regression and attained complete sexual quiescence. Based on our study, it is suggested that long term exposure to blue LED light of low intensity may induce gonadal regression even under long-day conditions (LD 16:8), while exposure to green and red lights appears to maintain a constant photosensitivity after one complete gonadal cycle.

  12. Electrodynamics of the equatorial F-region ionosphere during pre-sunrise period

    Directory of Open Access Journals (Sweden)

    S. R. Prabhakaran Nayar

    2009-01-01

    Full Text Available The electrodynamics of the pre-sunrise equatorial F-region is investigated using HF Doppler radar and digital ionosonde. The observations are limited to those days for which the radar probing frequency is below the foF2 value. The ionosphere observation using HF Doppler radar exhibit interesting features during pre-sunrise period similar to the post sunset pre-reversal enhancement. The most striking feature observed during pre-sunrise period is the sudden downward excursion in the vertical drift around local sunrise followed by an upward turning. Pre-sunrise observations of vertical plasma drift and the sunrise downward excursion followed by an upward turning after the ground sunrise related to the zonal electric field at the equatorial F-region are the most significant results not reported earlier.

  13. EFFECT OF LIGHT INTENSITY ON THE TOTAL LIPID AND FATTY ACID COMPOSITION OF SIX STRAINS OF

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The effect of light intensity (1500 lx and 5000 lx) on the total lipid and fatty acid composition of six strains of marine diatoms Cylindrotheca fusiformis (B211), Phaeodactylum tricornutum (B114, B118 and B221) Nitzschia closterium (B222) and Chaetoceros gracilis (B13) was investigated. The total lipids of B13, B114, and B211 grown at 5000 lx were lower than those grown at 1500 lx. No evident changes were observed in B118, B221 and B222. Fatty acid composition changed considerably at different light intensity although no consistent correlation between the relative proportion of a single FA and light intensity. The major fatty acids of the 6 strains were 14:0, 16:0, 16:1(n-7) and 20:5(n-3). Cylindrotheca fusiformis had high percentage of 20:4n-6 (9.2-10.9%). The total polyunsaturated fatty acid in all 6 strains decreased with increasing light intensity. The percentage of the highly unsaturated fatty acid eicosapentaenoic acid (EPA) decreased with increasing light intensity in all strains except Chaetoceros gracilis.

  14. Photolysis of Caged-GABA Rapidly Terminates Seizures In Vivo: Concentration and Light Intensity Dependence.

    Science.gov (United States)

    Wang, Dan; Yu, Zhixin; Yan, Jiaqing; Xue, Fenqin; Ren, Guoping; Jiang, Chenxi; Wang, Weimin; Piao, Yueshan; Yang, Xiaofeng

    2017-01-01

    The therapy of focal epilepsy remains unsatisfactory for as many as 25% of patients. The photolysis of caged-γ-aminobutyric acid (caged-GABA) represents a novel and alternative option for the treatment of intractable epilepsy. Our previous experimental results have demonstrated that the use of blue light produced by light-emitting diode to uncage ruthenium-bipyridine-triphenylphosphine-c-GABA (RuBi-GABA) can rapidly terminate paroxysmal seizure activity both in vitro and in vivo. However, the optimal concentration of RuBi-GABA, and the intensity of illumination to abort seizures, remains unknown. The aim of this study was to explore the optimal anti-seizure effects of RuBi-GABA by using implantable fibers to introduce blue light into the neocortex of a 4-aminopyridine-induced acute seizure model in rats. We then investigated the effects of different combinations of RuBi-GABA concentrations and light intensity upon seizure. Our results show that the anti-seizure effect of RuBi-GABA has obvious concentration and light intensity dependence. This is the first example of using an implantable device for the photolysis of RuBi-GABA in the therapy of neocortical seizure, and an optimal combination of RuBi-GABA concentration and light intensity was explored. These results provide important experimental data for future clinical translational studies.

  15. The effect of low light intensity on the maintenance of circadian synchrony in human subjects

    Science.gov (United States)

    Winget, C. M.; Lyman, J.; Beljan, J. R.

    1977-01-01

    The light-intensity threshold for humans is not known. In past space flights owing to power restrictions, light intensities have been minimal and reported to be as low as 15 ft. c. This study was conducted to determine whether the light (L)/dark (D) environment of 16L : 8D at the relatively low light intensity of 15 ft. c. was adequate for the maintenance of circadian synchrony in human subjects. Six healthy male subjects aged 20-23 years were exposed for 21 days to a 16L : 8D photoperiod. During the first 7 days the light intensity was 100 ft. c.; it was reduced to 15 ft. c. during the next 7 days and increased again to 100 ft. c. during the last 7 days of the study. Rectal temperature (RT) and heart rate (HR) were recorded continuously throughout the 21 days of the study. In the 100 ft. c. 16L : 8D the RT and HR rhythms remained stable and circadian throughout. When the light intensity was decreased to 15 ft. c. the periodicity of the HR rhythm was significantly decreased and this rhythm showed marked instability. In contrast the period of the RT rhythm did not change but a consistent phase delay occurred due to a delay in the lights-on associated rise in RT. These divergent effects on these two rhythms in internal desynchronization and performance decrement during the 15 ft. c. exposure. The data emphasize the need for establishing accurately the minimal lighting requirements for the maintenance of circadian rhythms of humans in confined environments.

  16. Methodology for assessing the lighting of pedestrian crossings based on light intensity parameters

    Directory of Open Access Journals (Sweden)

    Tomczuk Piotr

    2017-01-01

    Full Text Available One of the possible preventive measures that could improve safety at crossings is to assess the state of illumination of the lighting installation located in the transition area for pedestrians. The City of Warsaw has undertaken to comprehensively assess the pedestrian crossings to determine the level of road safety and the condition of lighting. The lighting conditions related to pedestrian crossings without traffic lights in three central districts of the city were investigated. The conducted field research and the work of the team of experts lead to the development of tools to assess the level of risk due to the lighting conditions measured at night. The newly developed and used method of assessment and the experience gained should provide a valuable contribution to the development of uniform risk assessment rules for pedestrian crossings in Poland. The authors of this paper have attempted to systematize the description of the method of evaluation of the lighting installed in the area of pedestrian crossings.

  17. True Color of Mars - Pathfinder Sol 39 Sunrise

    Science.gov (United States)

    1999-01-01

    Sunrise, sol 39. This true color, pre-sunrise image (approximately 0530LST) is composed of six images extending 30 o in azimuth and 45 o in elevation and shows the brownish gray predawn sky. A description of the techniques used to generate this color image from IMP data can be found in Maki et al., 1999. Note: a calibrated output device is required accurately reproduce the correct colors.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The IMP was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal investigator.

  18. A Tale of Two Emergences: Sunrise II Observations of Emergence Sites in a Solar Active Region

    Science.gov (United States)

    Centeno, R.; Blanco Rodríguez, J.; Del Toro Iniesta, J. C.; Solanki, S. K.; Barthol, P.; Gandorfer, A.; Gizon, L.; Hirzberger, J.; Riethmüller, T. L.; van Noort, M.; Orozco Suárez, D.; Berkefeld, T.; Schmidt, W.; Martínez Pillet, V.; Knölker, M.

    2017-03-01

    In 2013 June, the two scientific instruments on board the second Sunrise mission witnessed, in detail, a small-scale magnetic flux emergence event as part of the birth of an active region. The Imaging Magnetograph Experiment (IMaX) recorded two small (∼ 5\\prime\\prime ) emerging flux patches in the polarized filtergrams of a photospheric Fe i spectral line. Meanwhile, the Sunrise Filter Imager (SuFI) captured the highly dynamic chromospheric response to the magnetic fields pushing their way through the lower solar atmosphere. The serendipitous capture of this event offers a closer look at the inner workings of active region emergence sites. In particular, it reveals in meticulous detail how the rising magnetic fields interact with the granulation as they push through the Sun’s surface, dragging photospheric plasma in their upward travel. The plasma that is burdening the rising field slides along the field lines, creating fast downflowing channels at the footpoints. The weight of this material anchors this field to the surface at semi-regular spatial intervals, shaping it in an undulatory fashion. Finally, magnetic reconnection enables the field to release itself from its photospheric anchors, allowing it to continue its voyage up to higher layers. This process releases energy that lights up the arch-filament systems and heats the surrounding chromosphere.

  19. Inactivation of microalgae in ballast water with pulse intense light treatment.

    Science.gov (United States)

    Feng, Daolun; Shi, Jidong; Sun, Dan

    2015-01-15

    The exotic emission of ballast water has threatened the coastal ecological environment and people's health in many countries. This paper firstly introduces pulse intense light to treat ballast water. 99.9 ± 0.09% inactivation of Heterosigma akashiwo and 99.9 ± 0.16% inactivation of Pyramimonas sp. are observed under treatment conditions of 350 V pulse peak voltage, 15 Hz pulse frequency, 5 ms pulse width and 1.78 L/min flow rate. The energy consumption of the self-designed pulse intense light treatment system is about 2.90-5.14 times higher than that of the typical commercial UV ballast water treatment system. The results indicate that pulse intense light is an effective technique for ballast water treatment, while it is only a competitive one when drastic decreasing in energy consumption is accomplished. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. The two-loop sunrise integral and elliptic polylogarithms

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Luise; Weinzierl, Stefan [Institut fuer Physik, Johannes Gutenberg-Universitaet Mainz (Germany); Bogner, Christian [Institut fuer Physik, Humboldt-Universitaet zu Berlin (Germany)

    2016-07-01

    In this talk, we present a solution for the two-loop sunrise integral with arbitrary masses around two and four space-time dimensions in terms of a generalised elliptic version of the multiple polylogarithms. Furthermore we investigate the elliptic polylogarithms appearing in higher orders in the dimensional regularisation ε of the two-dimensional equal mass solution. Around two space-time dimensions the solution consists of a sum of three elliptic dilogarithms where the arguments have a nice geometric interpretation as intersection points of the integration region and an elliptic curve associated to the sunrise integral. Around four space-time dimensions the sunrise integral can be expressed with the ε{sup 0}- and ε{sup 1}-solution around two dimensions, mass derivatives thereof and simpler terms. Considering higher orders of the two-dimensional equal mass solution we find certain generalisations of the elliptic polylogarithms appearing in the ε{sup 0}- and ε{sup 1}-solutions around two and four space-time dimensions. We show that these higher order-solutions can be found by iterative integration within this class of functions.

  1. Effect of light intensity on ovarian gene expression, reproductive performance and body weight of rabbit does.

    Science.gov (United States)

    Sun, Liangzhan; Wu, Zhenyu; Li, Fuchang; Liu, Lei; Li, Jinglin; Zhang, Di; Sun, Chaoran

    2017-08-01

    The objective of the experiment was to find the minimum light intensity which could improve reproduction by examining its effect on ovarian gene expression, reproductive performance and body weight of rabbit does with three different light intensities: 60 (L), 80 (M), and 100 (H)lx. A total of 144 Rex-rabbits submitted to a 49-day reproductive regimen were used in this study. Ovaries were collected and relative abundance of mRNA for ovarian proteins of interest was examined with real-time PCR. Amount of protein for proteins of interest was examined by immunohistochemistry. Reproductive performance and doe bodyweight of the first three consecutive reproductive periods after initiation of the light intensity treatments were evaluated. The results provided evidence that light intensity had no effect on relative abundance of estradiol receptor-α (ER-α), follicle stimulating hormone receptor (FSHR), luteinizing hormone receptor (LHR), gonadotropin releasing hormone receptor 1 (GnRHR1) and progesterone receptor (PGR) mRNA. The relative abundance of growth hormone receptor (GHR) mRNA was, however, greater in Group L than M and H (P0.05). The bodyweight of the does in Group L was greater than the other two groups at first insemination, second insemination and the second postpartum period (P0.05). These observations suggest that light intensity between 60 and 100lx has no effect on the reproductive performance of rabbit does, however, the amounts of GHR mRNA and growth hormone (GH) protein were affected and the greater light intensity had a negative effect on bodyweight between the time of the first insemination and the second partum period. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Effect of ambient temperature and light intensity on physiological reactions of heavy broiler chickens.

    Science.gov (United States)

    Olanrewaju, H A; Purswell, J L; Collier, S D; Branton, S L

    2010-12-01

    The effects of ambient temperature, light intensity, and their interaction on blood acid-base balance, metabolites, and electrolytes in broiler chickens under environmentally controlled conditions were examined in 2 trials. The experiment consisted of a factorial arrangement of treatments in a randomized complete block design. The 9 treatments consisted of 3 levels of temperatures (low = 15.6°C; moderate = 21.1°C; high = 26.7°C) from 21 to 56 d of age and 3 levels of light intensities (0.5, 3.0, 20 lx) from 8 to 56 d of age at 50% RH. A total of 540 Ross 708 chicks were randomly distributed into 9 environmentally controlled chambers (30 male and 30 female chicks/chamber) at 1 d of age. Feed and water were provided ad libitum. Venous blood samples were collected on d 21 (baseline), 28, 42, and 56. High ambient temperature significantly (P ≤ 0.05) reduced BW, partial pressure of CO(2), bicarbonate, hematocrit, hemoglobin, K(+), and Na(+) along with significantly (P ≤ 0.05) elevated pH level, Cl(-), glucose, osmolality, and anion gap concentrations. Partial pressure of O(2) was slightly increased in response to increased ambient temperature. There was no effect of light intensity on most of the blood variables examined. Acid-base regulation during high ambient temperature and light intensity exposure did not deteriorate despite a lower partial pressure of CO(2), which consequently increased blood pH because of a compensatory decrease in HCO(3)(-) concentration. Plasma corticosterone was not affected by temperature, light intensity, or their interaction. These results indicate that continuous exposure of broiler chickens to varying light intensities had a minor effect on physiological blood variables, whereas high ambient temperature markedly affected various blood variables without inducing stress in broilers.

  3. Photon counting range-intensity image strategy in low-light level environments.

    Science.gov (United States)

    Zhang, Zijing; Xu, Yuannan; Wu, Long; Zhang, Yong; Zhao, Yuan; Su, Jianzhong

    2014-04-15

    We present a photon counting range-intensity image strategy based on a single-photon detector in low-light level environments. In this Letter, a composite modulation method over the pulse sequence was used for the first time, to the best of our knowledge, which combined pulse-position modulation and pulse-intensity modulation. This composite modulation method could obtain range and intensity of the detected target at the same time. Besides, angle-angle information could be provided from the scanner or detector array. Thus, a range-intensity image of the target became feasible. For demonstrating this photon counting range-intensity image strategy, a proof-of-principle laboratory system was established. In low-light level environments, a range-intensity image of multiple similar targets was obtained successfully with the range accuracy of centimeter level and intensity error of 1%. Compared with the range image, a range-intensity image could better reorganize and identify similar targets.

  4. Construction and temporal behaviour study of multi RLC intense light pulses for dermatological applications.

    Science.gov (United States)

    Hamoudi, Walid K; Ismail, Raid A; Shakir, Hussein A

    2017-10-01

    Driving a flash lamp in an intense pulsed light system requires a high-voltage DC power supply, capacitive energy storage and a flash lamp triggering unit. Single, double, triple and quadruple-mesh discharge and triggering circuits were constructed to provide intense light pulses of variable energy and time durations. The system was treated as [Formula: see text] circuit in some cases and [Formula: see text] circuit in others with a light pulse profile following the temporal behaviour of the exciting current pulse. Distributing the energy delivered to one lamp onto a number of LC meshes permitted longer current pulses, and consequently increased the light pulse length. Positive results were obtained when using the system to treat skin wrinkles.

  5. Light fields with an axially expanded intensity distribution for stable three-dimensional optical trapping.

    Science.gov (United States)

    Zwick, Susanne; Schaub, Christian; Haist, Tobias; Osten, Wolfgang

    2010-09-13

    We introduce a new kind of light field to improve and simplify the trapping process of axially displaced particles. To this end we employ a light field with an axially expanded intensity distribution, which at the same time enables stable axial trapping. We present simulations of the axial intensity distribution of the novel trapping field and first experimental results, which demonstrate the improvement of the reliability of the axial trapping process. The method can be used to automate trapping of particles that are located outside of the focal plane of the microscope.

  6. Performance of amorphous and microcrystalline silicon pin solar cells under variable light intensity

    Energy Technology Data Exchange (ETDEWEB)

    Nath, M.; Chakraborty, S.; Chatterjee, P. [Energy Research Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India); Kim, K.H.; Johnson, E.V.; Roca i Cabarrocas, P. [Laboratoire de Physique des Interfaces et des Couches Minces, Ecole Polytechnique, CNRS, 91128 Palaiseau (France)

    2010-04-15

    We have studied the solar cell behaviour under variable light intensity (VLI) of a standard a-Si:H pin solar cell with a wide band gap a-SiC:H emitter layer, and microcrystalline ({mu}c)-Si:H solar cells of different degrees of crystallinity, using experiments in conjunction with detailed electrical-optical modelling. Both experiments and modelling reveal that whereas the fill factor (FF) of the a-Si:H pin cell decreases with increasing light intensity, starting from a low applied light bias, that of the {mu}c-Si:H cells increases with light intensity over a major part of this range. This fact enables one to attain the maximum of the open-circuit voltage - fill factor product (V{sub oc} x FF) at 1 to 2 suns intensity for the latter case; however this is not achieved for the a-Si:H cell. Using modelling we try to understand this difference in behaviour of the FF under VLI for the two types of cells. We also predict under what conditions it would be possible to shift the (V{sub oc} x FF){sub max} for the a-Si:H cell towards one sun intensity. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. Fractional CO2laser versus intense pulsed light in treating striae distensae

    Directory of Open Access Journals (Sweden)

    Moustafa Adam El Taieb

    2016-01-01

    Full Text Available Context: Striae distensae are linear atrophic dermal scars covered with flat atrophic epidermis. They may cause disfigurement, especially in females. Many factors may cause striae distensae such as steroids, obesity, and pregnancy. Although there is no standard treatment for striae; many topical applications, peeling, and light and laser systems have been tried. Aims: To evaluate and compare the efficacy of fractional CO2laser with intense pulse light in treating striae distensae. Subjects and Methods: Forty patients with striae distensae were recruited. Twenty of them were treated by fractional CO2laser and 20 were treated with intense pulse light. Length and width of the largest striae were measured pre- and post-treatment. Patient satisfaction was also evaluated and graded. Patients were photographed after each treatment session and photos were examined by a blinded physician who had no knowledge about the cases. Results: Both groups showed significant improvement after treatments (P 0.05. Conclusions: The current study has provided supportive evidence to the effectiveness of both fractional CO2laser and intense pulse light as treatments for striae distensae. Fractional CO2laser was found to be more effective in the treatment of striae distensae compared with intense pulse light.

  8. Contrast in light intensity, rather than day length, influences the behavior and health of broiler chickens.

    Science.gov (United States)

    Blatchford, R A; Archer, G S; Mench, J A

    2012-08-01

    Day length and intensity are commonly manipulated aspects of the light environment in commercial broiler production. Both influence circadian rhythms, but it is unclear if they do this independently or synergistically. The effect of light:dark (20L:4D, 16L:8D) and intensity contrasts (1 lx:0.5 lx, 200 lx:0.5 lx) on broiler behavior and health (n=1,004, 4 replicates/treatment) was evaluated. Activity was measured using passive infrared detection, and feeding activity was measured by the amount of feed consumed/h over one 24-h period each week. Broilers were gait scored and weighed at 6 wk of age. Following euthanasia, eyes were dissected from 30 birds/treatment. Behavior and performance were analyzed using the GLM, gait score using the Kruskal-Wallis test, and eye measures using a MANOVA. The 200 lx birds were more active (P=0.03) and fed more (P=0.001) during the photophase but were less active (P=0.02) and fed less (Plight:dark, with 16:8 having greater back-to-front eye diameters than 20:4 (13.30±0.10 mm vs. 13.00±0.10 mm, P=0.02). There were no interactions. These results indicated that light intensity, not day length, was the major factor affecting broiler behavior and health under these lighting conditions. Low contrast light intensity dampened behavioral rhythms and had possible health effects.

  9. Light intensity alters the extent of arsenic toxicity in Helianthus annuus L. seedlings.

    Science.gov (United States)

    Yadav, Geeta; Srivastava, Prabhat Kumar; Singh, Vijay Pratap; Prasad, Sheo Mohan

    2014-06-01

    The present study is aimed at assessing the extent of arsenic (As) toxicity under three different light intensities-optimum (400 μmole photon m(-2) s(-1)), sub-optimum (225 μmole photon m(-2) s(-1)), and low (75 μmole photon m(-2) s(-1))-exposed to Helianthus annuus L. var. DRSF-113 seedlings by examining various physiological and biochemical parameters. Irrespective of the light intensities under which H. annuus L. seedlings were grown, there was an As dose (low, i.e., 6 mg kg(-1) soil, As1; and high, i.e., 12 mg kg(-1) soil, As2)-dependent decrease in all the growth parameters, viz., fresh mass, shoot length, and root length. Optimum light-grown seedlings exhibited better growth performance than the sub-optimum and low light-grown seedlings; however, low light-grown plants had maximum root and shoot lengths. Accumulation of As in the plant tissues depended upon its concentration used, proximity of the plant tissue, and intensity of the light. Greater intensity of light allowed greater assimilation of photosynthates accompanied by more uptake of nutrients along with As from the medium. The levels of chlorophyll a, b, and carotenoids declined with increasing concentrations of As. Seedlings acquired maximum Chl a and b under optimum light which were more compatible to face As1 and As2 doses of As, also evident from the overall status of enzymatic (SOD, POD, CAT, and GST) and non-enzymatic antioxidant (Pro).

  10. Effects of plant size, temperature, and light intensity on flowering of Phalaenopsis hybrids in Mediterranean greenhouses.

    Science.gov (United States)

    Paradiso, Roberta; De Pascale, Stefania

    2014-01-01

    Mediterranean greenhouses for cultivation of Phalaenopsis orchids reproduce the warm, humid, and shaded environment of tropical underbrush. Heating represents the highest production cost, due to the high thermal requirements and the long unproductive phase of juvenility, in which plants attain the critical size for flowering. Our researches aimed to investigate the effect of plant size, temperature, and light intensity, during the phase of flower induction, on flowering of modern genotypes selected for Mediterranean greenhouses. Three experiments were carried out to compare (i) plant size: reduced size versus size considered optimal for flowering (hybrids "Sogo Yukidian," "Chain Xen Diamond," and "Pinlong"); (ii) temperature: moderate reduction of temperature versus standard thermal regime (hybrid "Premium"); (iii) light intensity: supplemental lighting versus reference light intensity (hybrid "Premium"). The premature exposure of plants to the inductive treatment delayed the beginning of flowering and reduced the flower stem quality, in all the tested hybrids. In "Premium," the lower temperature did not affect flowering earliness and commercial quality of flower stems compared to the standard regime, whereas it promoted stem branching. In the same hybrid, supplemental lighting anticipated flowering and promoted the emission of the second stem and the stem branching, compared to the reference light regime.

  11. Temporal intensity correlation of light scattered by a hot atomic vapor

    CERN Document Server

    Dussaux, A; Guerin, W; Alibart, O; Tanzilli, S; Vakili, F; Kaiser, R

    2016-01-01

    We present temporal intensity correlation measurements of light scattered by a hot atomic vapor. Clear evidence of photon bunching is shown at very short time-scales (ns) imposed by the Doppler broadening of the hot vapor. Moreover, we demonstrate that some relevant information about the scattering process, such as the ratio of single to multiple scattering, can be deduced from the measured intensity correlation function. These measurements confirm the interest of temporal intensity correlation measurements to access non-trivial spectral features, with potential applications in astrophysics.

  12. Low-intensity treadmill exercise and/or bright light promote neurogenesis in adult rat brain

    Institute of Scientific and Technical Information of China (English)

    Sung Jin Kwon; Jeongsook Park; So Yun Park; Kwang Seop Song; Sun Tae Jung; So Bong Jung; Ik Ryeul Park; Wan Sung Choi; Sun Ok Kwon

    2013-01-01

    The hippocampus is a brain region responsible for learning and memory functions. The purpose of this study was to investigate the effects of low-intensity exercise and bright light exposure on neurogenesis and brain-derived neurotrophic factor expression in adult rat hippocampus. Male Sprague-Dawley rats were randomly assigned to control, exercise, light, or exercise + light groups (n = 9 per group). The rats in the exercise group were subjected to treadmill exercise (5 days per week, 30 minutes per day, over a 4-week period), the light group rats were irradiated (5 days per week, 30 minutes per day, 10 000 lx, over a 4-week period), the exercise + light group rats were subjected to treadmill exercise in combination with bright light exposure, and the control group rats remained sedentary over a 4-week period. Compared with the control group, there was a significant increase in neurogenesis in the hippocampal dentate gyrus of rats in the exercise, light, and exercise + light groups. Moreover, the expression level of brain-derived neurotrophic factor in the rat hippocampal dentate gyrus was significantly higher in the exercise group and light group than that in the control group. Interestingly, there was no significant difference in brain-derived neurotrophic factor expression between the control group and exercise + light group. These results indicate that low-intensity treadmill exercise (first 5 minutes at a speed of 2 m/min, second 5 minutes at a speed of 5 m/min, and the last 20 minutes at a speed of 8 m/min) or bright-light exposure therapy induces positive biochemical changes in the brain. In view of these findings, we propose that moderate exercise or exposure to sunlight during childhood can be beneficial for neural development.

  13. INFLUENCE OF HIGH LIGHT INTENSITY ON THE CELLS OF CYANOBACTERIA ANABAENA VARIABILIS SP. ATCC 29413

    Directory of Open Access Journals (Sweden)

    OPRIŞ SANDA

    2012-12-01

    Full Text Available In this article is presented the result of research regardind the effect of high light intensity on the cells of Anabaena variabilis sp. ATCC 29413, the main objective is to study the adaptation of photosynthetic apparatus to light stress. Samples were analyzed in the present of herbicide diuron (DCMU which blocks electron flow from photosystem II and without diuron. During treatment maximum fluorescence and photosystems efficiency are significantly reduced, reaching very low values compared with the blank, as a result of photoinhibition installation. Also by this treatment is shown the importance of the mechanisms by which cells detect the presence of light stress and react accordingly.

  14. Photoprotective capacity of non-photochemical quenching in plants acclimated to different light intensities.

    Science.gov (United States)

    Ware, Maxwell A; Belgio, Erica; Ruban, Alexander V

    2015-12-01

    Arabidopsis plants grown at low light were exposed to a gradually increasing actinic light routine. This method allows for the discerning of the photoprotective component of NPQ, pNPQ and photoinhibition. They exhibited lower values of Photosystem II (PSII) yield in comparison to high-light grown plants, and higher calculated dark fluorescence level (F'o calc.) than the measured one (F'o act.). As a result, in low-light grown plants, the values of qP measured in the dark appeared higher than 1. Normally, F'o act. and F'o calc. match well at moderate light intensities but F'o act. becomes higher at increasing intensities due to reaction centre (RCII) damage; this indicates the onset of photoinhibition. To explain the unusual increase of qP in the dark in low-light grown plants, we have undertaken an analysis of PSII antenna size using biochemical and spectroscopic approaches. Sucrose gradient separation of thylakoid membrane complexes and fast fluorescence induction experiments illustrated that the relative PSII cross section does not increase appreciably with the rise in PSII antenna size in the low-light grown plants. This suggests that part of the increased LHCII antenna is less efficiently coupled to the RCII. A model based upon the existence of an uncoupled population LHCII is proposed to explain the discrepancies in calculated and measured values of F'o.

  15. Light intensity on growth, leaf micromorphology and essential oil production of Ocimum gratissimum

    Directory of Open Access Journals (Sweden)

    Valéria Ferreira Fernandes

    2013-06-01

    Full Text Available Light conditions can promote the growth and development of plants and contribute to increase the essential oil production of commercially cultivated medicinal and aromatic species. In view of the great importance of Ocimum gratissimum L., Lamiaceae, as an aromatic plant, the objective of this work was to determine the effect of light intensities (approximately 4, 7, 11 and 20 mol m-2 d-1 on growth, foliar micromorphology, essential oil content, yield and chemical composition of O. gratissimum. Biomass production of different organs, root:shoot ratio and leaf mass per area were found to linearly increase with increased light availability, whereas stem dry matter fraction, number of leaves, leaf area and plant height have increased up to 10 mol m-2 d-1 and decreased from this value. The tector trichomes density increased with increased light availability, but there was no effect of light treatments on the glandular trichomes density and essential oil content. Regardless of the light level, the major component of the essential oil was eugenol. The essential oil yield per plant increased linearly with light intensity as a direct effect of increased leaf biomass under similar conditions.

  16. Genetic analysis of biomass and photosynthetic parameters in wheat grown in different light intensities

    Institute of Scientific and Technical Information of China (English)

    Hongwei Li; Gui Wang; Qi Zheng; Bin Li; Ruilian Jing; Zhensheng Li

    2014-01-01

    Growth light intensities largely determine photo-synthesis, biomass, and grain yield of cereal crops. To explore the genetic basis of light responses of biomass and photosynthetic parameters in wheat (Triticum aestivum L.), a quantitative trait locus (QTL) analysis was carried out in a doubled haploid (DH) population grown in low light (LL), medium light (ML), and high light (HL), respectively. The results showed that the wheat seedlings grown in HL produced more biomass with lower total chlorophyll content (Chl), carotenoid content, and maximum photochemical efficiency of photosystem II (Fv/Fm) while the wheat seed-lings grown in LL produced less biomass with higher Chl compared with those grown in ML. In total, 48 QTLs were identified to be associated with the investigated parameters in relation to growth light intensities. These QTLs were mapped to 15 chromosomes which individually explained 6.3%-36.0% of the phenotypic variance, of which chromo-somes 3A, 1D, and 6B were specifically involved in LL response, 5D and 7A specifically involved in ML response, and 4B specifically involved in HL response. Several light-responsive QTLs were co-located with QTLs for photosyn-thetic parameters, biomass, and grain weight under various conditions which may provide new hints to uncover the genetic control of photosynthesis, biomass, and grain weight.

  17. Monitoring of transient cavitation induced by ultrasound and intense pulsed light in presence of gold nanoparticles.

    Science.gov (United States)

    Sazgarnia, Ameneh; Shanei, Ahmad; Shanei, Mohammad Mahdi

    2014-01-01

    One of the most important challenges in medical treatment is invention of a minimally invasive approach in order to induce lethal damages to cancer cells. Application of high intensity focused ultrasound can be beneficial to achieve this goal via the cavitation process. Existence of the particles and vapor in a liquid decreases the ultrasonic intensity threshold required for cavitation onset. In this study, synergism of intense pulsed light (IPL) and gold nanoparticles (GNPs) has been investigated as a means of providing nucleation sites for acoustic cavitation. Several approaches have been reported with the aim of cavitation monitoring. We conducted the experiments on the basis of sonochemiluminescence (SCL) and chemical dosimetric methods. The acoustic cavitation activity was investigated by determining the integrated SCL signal acquired over polyacrylamide gel phantoms containing luminol in the presence and absence of GNPs in the wavelength range of 400-500 nm using a spectrometer equipped with cooled charged coupled devices (CCD) during irradiation by different intensities of 1 MHz ultrasound and IPL pulses. In order to confirm these results, the terephthalic acid chemical dosimeter was utilized as well. The SCL signal recorded in the gel phantoms containing GNPs at different intensities of ultrasound in the presence of intense pulsed light was higher than the gel phantoms without GNPs. These results have been confirmed by the obtained data from the chemical dosimetry method. Acoustic cavitation in the presence of GNPs and intense pulsed light has been suggested as a new approach designed for decreasing threshold intensity of acoustic cavitation and improving targeted therapeutic effects. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Light Intensity and Carbon Dioxide Availability Impact Antioxidant Activity in Green Onions (Allium fistulosumm L)

    Science.gov (United States)

    Levine, Lanfang; Bisbee, Patricia; Pare, Paul

    The prospect of long-duration manned space missions poses many challenges, including the development of a sustainable life support system and effective methods of space-radiation protection. To mitigate the risk of increased space-radiation, functional foods rich in antioxidant properties such as green onions are of particular interest. However it has yet to be established whether antioxidant properties can be preserved or enhanced in space environment where carbon dioxide, lighting intensity, gravity and pressure differ from which plants have acclimated to on earth. In this study, green onions (Allium fistulosumm L. cultivar Kinka) rich in antioxidant flavonoids are used as a model system to investigate variations in antioxidant capacity with plants grown under varying light intensities and CO2 concentrations. The antioxidant potential is determined using both radical cation scavenging and oxygen radical absorbance assays. For all light intensities assayed, antioxidant potential in water extract of green onions per gram biomass declined with CO2 increases up to 1200 ppm, and then leveled off with further CO2 increase to 4000 ppm. This inverse carbon dioxide versus antioxidant activity correlation suggests lower accumulation rates for water soluble antioxidant compounds compared to total biomass under increasing CO2 concentrations. The effect of increasing atmospheric CO2 concentration on antioxidant activity of ethanol extracts were light intensity dependent. The implications of these findings are discussed in the context of traditional plant antioxidants including vitamin C and the major onion flavonoid quercetin.

  19. Influence of ammonium chloride feeding time and light intensity on the cultivation of Spirulina (Arthrospira) platensis.

    Science.gov (United States)

    Bezerra, Raquel Pedrosa; Matsudo, Marcelo Chuei; Converti, Attilio; Sato, Sunao; de Carvalho, João Carlos Monteiro

    2008-06-01

    This study dealt with the influence of both the feeding time and light intensity on the fed-batch culture of the cyanobacterium Spirulina (Arthrospira) platensis using ammonium chloride as a nitrogen source. For this purpose, a 2(2) plus star central composite experimental design combined with response surface methodology was employed, and the maximum cell concentration (X(m)), the cell productivity (P(X)), and the yield of biomass on nitrogen (Y(X/N)) were selected as the response variables. The optimum values of X(m) (1,833 mg L(-1)) and Y(X/N) (5.9 g g(-1)) estimated by the model at light intensity of 13 klux and feeding time of 17.2 days were very close to those obtained experimentally under these conditions (X(m) = 1,771 +/- 41 mg L(-1); Y(X/N) = 5.7 +/- 0.17 g g(-1)). The cell productivity was a decreasing function of the ammonium chloride feeding time and a quadratic function of the light intensity. The protein and lipid contents of dry biomass collected at the end of cultivations were shown to decrease with increasing light intensity.

  20. Intense pulsed light therapy (IPL) induced iritis following treatment for a medial canthal capillary malformation.

    Science.gov (United States)

    Crabb, Matthew; Chan, Weng Onn; Taranath, Deepa; Huilgol, Shyamala C

    2014-11-01

    The popularity of intense pulsed light (IPL) therapy continues to increase due to its relative safety, high skin coverage rate and ability to treat both vascular and pigmented lesions. An often-overlooked risk is the potential for IPL-induced ocular damage. The damage sustained can cause significant, persistent morbidity and can occur even with very limited IPL exposure to the eye.

  1. Selected List of Low Energy Beam Transport Facilities for Light-Ion, High-Intensity Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Prost, L. R. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)

    2016-02-17

    This paper presents a list of Low Energy Beam Transport (LEBT) facilities for light-ion, high-intensity accelerators. It was put together to facilitate comparisons with the PXIE LEBT design choices. A short discussion regarding the importance of the beam perveance in the choice of the transport scheme follows.

  2. An evaluation of light intensity functions for determination of shaded reference stream metabolism.

    Science.gov (United States)

    Zell, Chris; Hubbart, Jason A

    2012-04-30

    The performance of three single-station whole stream metabolism models were evaluated within three shaded, seasonally hypoxic, Missouri reference streams using high resolution (15-minute) dissolved oxygen (DO), temperature, and light intensity data collected during the summers (July-September) of 2006-2008. The model incorporating light intensity data consistently achieved a lower root mean square error (median RMSE = 0.20 mg L(-1)) relative to models assuming sinusoidal light intensity functions (median RMSE = 0.28 mg L(-1)) and constant diel temperature (median RMSE = 0.53 mg L(-1)). Incorporation of site-specific light intensity into metabolism models better predicted morning DO concentrations and exposure to hypoxic conditions in shaded study streams. Model choice significantly affected (p streams. Quantifying these process combinations in best-available or least-disturbed (i.e., reference) systems advances our understanding of regional dissolved oxygen expectations and informs environmental management policy. Additional research is warranted to better link landscape processes with distributed sources that contribute to community respiration.

  3. The intense pulsed light systems : new treatment possibilities for vascular, pigmented lesions and hair removal

    NARCIS (Netherlands)

    C.A. Schroeter (Careen)

    2004-01-01

    textabstractGiven all of the differences in between laser and IPLS devices and the need for additional information in IPLS treatment applications, the aim of this study was to evaluate new treatment possibilities using Intense Pulsed Light Sources and to address the following questions: 1. What are

  4. Effects of phosphorus concentration and light intensity on the biomass composition of Arthrospira (Spirulina) platensis.

    Science.gov (United States)

    Markou, Giorgos; Chatzipavlidis, Iordanis; Georgakakis, Dimitris

    2012-08-01

    This paper presents the effects of various phosphorus concentrations (10, 50, 250 and 500 mg l(-1) K(2)HPO(4)) on the biomass production and composition of Arthrospira (Spirulina) platensis in relation to light intensity (24, 42 and 60 μE m(-2) s(-1)). The maximum biomass production was 3,592 ± 392 mg l(-1) and this was observed in 250 mg l(-1) K(2)HPO(4) at 60 μE m(-2) s(-1) light intensity after 32 days of cultivation. A maximum specific growth rate (μ(max)) of 0.55 d(-1) was obtained in 500 mg l(-1) K(2)HPO(4) at 60 μE m(-2) s(-1). The protein, lipid and chlorophyll contents of the biomass varied from 33.59 to 60.57 %, 5.34 to 13.33 % and 0.78 to 2.00 %, respectively. The most significant finding was that phosphorus limitation (10 mg l(-1) K(2)HPO(4)) caused a drastic increase of the carbohydrate content (59.64 %). The effect of phosphorus limitation on the carbohydrate content was independent of the light intensity. The accumulated carbohydrates are proposed to be used as substrate for biofuel generation via one of the appropriate biomass energy conversion technologies. Also, it was observed that phosphorus removal is a function of biomass density, phosphorus concentration and light intensity.

  5. Detection of light and vibration modulates bioluminescence intensity in the glowworm, Arachnocampa flava.

    Science.gov (United States)

    Mills, Rebecca; Popple, Julie-Anne; Veidt, Martin; Merritt, David John

    2016-04-01

    Glowworms are larval fungus gnats that emit light from a specialised abdominal light organ. The light attracts small arthropod prey to their web-like silk snares. Larvae glow throughout the night and can modulate their bioluminescence in response to sensory input. To better understand light output regulation and its ecological significance, we examined the larvae's reaction to light exposure, vibration and sound. Exposure to a 5-min light pulse in the laboratory causes larvae to exponentially decrease their light output over 5-10 min until they completely switch off. They gradually return to pre-exposure levels but do not show a rebound. Larvae are most sensitive to ultraviolet light, then blue, green and red. Vibration of the larval snares results in a several-fold increase in bioluminescence over 20-30 s, followed by an exponential return to pre-exposure levels over 15-30 min. Under some conditions, larvae can respond to vibration by initiating bioluminescence when they are not glowing; however, the response is reduced compared to when they are glowing. We propose that inhibitory and excitatory mechanisms combine to modulate bioluminescence intensity by regulating biochemical reactions or gating the access of air to the light organ.

  6. Associations of Low- and High-Intensity Light Activity with Cardiometabolic Biomarkers.

    Science.gov (United States)

    Howard, Bethany; Winkler, Elisabeth A H; Sethi, Parneet; Carson, Valerie; Ridgers, Nicola D; Salmon, J O; Healy, Genevieve N; Owen, Neville; Dunstan, David W

    2015-10-01

    Light-intensity physical activity (LIPA) accounts for much of adults' waking hours (≈40%) and substantially contributes to overall daily energy expenditure. Encompassing activity behaviors of low intensity (standing with little movement) to those of higher intensity (slow walking), LIPA is ubiquitous, yet little is known about how associations with health may vary depending on its intensity. We examined the associations of objectively assessed LIPA (categorized as either low LIPA [LLPA] or high LIPA [HLPA]) and moderate- to vigorous-intensity activity with cardiometabolic risk biomarkers. Cardiometabolic biomarkers were measured in 4614 US adults (47 ± 17 yr) who participated in the 2003-2004 and 2005-2006 National Health and Nutrition Examination Survey cycles. Multiple linear regression analyses examined the associations of three accelerometer-derived physical activity (SD increment per day) intensity categories (LLPA, 100-761 counts per minute; HLPA, 762-1951 counts per minute; moderate-intensity physical activity [MPA], 1952-5724 counts per minute; vigorous-intensity physical activity [VPA], ≥5725 counts per minute) with cardiometabolic biomarkers, adjusting for potential sociodemographic, behavioral, and medical confounders. All intensities of physical activity were beneficially associated with waist circumference, C-reactive protein, triglycerides, fasting insulin, β-cell function, and insulin sensitivity (P activity intensities showed significant associations with systolic blood pressure (LLPA), body mass index, HDL cholesterol, fasting glucose, and 2-h plasma glucose (HLPA, MPA, and VPA). Generally, effect size increased with intensity of physical activity. Overall, further adjustment for waist circumference attenuated associations with MPA and VPA to a greater extent than associations with LLPA and HLPA. The cross-sectional findings provide novel evidence for the potential benefits of increasing both LLPA and HLPA. They further reinforce the

  7. A high-fidelity photon gun: intensity-squeezed light from a single molecule

    CERN Document Server

    Chu, Xiao-Liu; Sandoghdar, Vahid

    2016-01-01

    A two-level atom cannot emit more than one photon at a time. As early as the 1980s, this quantum feature was identified as a gateway to "single-photon sources", where a regular excitation sequence would create a stream of light particles with photon number fluctuations below the shot noise. Such an intensity squeezed beam of light would be desirable for a range of applications such as quantum imaging, sensing, enhanced precision measurements and information processing. However, experimental realizations of these sources have been hindered by large losses caused by low photon collection efficiencies and photophysical shortcomings. By using a planar metallo-dielectric antenna applied to an organic molecule, we demonstrate the most regular stream of single photons reported to date. Measured intensity fluctuations reveal 2.2 dB squeezing limited by our detection efficiency, equivalent to 6.2 dB intensity squeezing right after the antenna.

  8. Economic analysis of greenhouse lighting: light emitting diodes vs. high intensity discharge fixtures.

    Directory of Open Access Journals (Sweden)

    Jacob A Nelson

    Full Text Available Lighting technologies for plant growth are improving rapidly, providing numerous options for supplemental lighting in greenhouses. Here we report the photosynthetic (400-700 nm photon efficiency and photon distribution pattern of two double-ended HPS fixtures, five mogul-base HPS fixtures, ten LED fixtures, three ceramic metal halide fixtures, and two fluorescent fixtures. The two most efficient LED and the two most efficient double-ended HPS fixtures had nearly identical efficiencies at 1.66 to 1.70 micromoles per joule. These four fixtures represent a dramatic improvement over the 1.02 micromoles per joule efficiency of the mogul-base HPS fixtures that are in common use. The best ceramic metal halide and fluorescent fixtures had efficiencies of 1.46 and 0.95 micromoles per joule, respectively. We also calculated the initial capital cost of fixtures per photon delivered and determined that LED fixtures cost five to ten times more than HPS fixtures. The five-year electric plus fixture cost per mole of photons is thus 2.3 times higher for LED fixtures, due to high capital costs. Compared to electric costs, our analysis indicates that the long-term maintenance costs are small for both technologies. If widely spaced benches are a necessary part of a production system, the unique ability of LED fixtures to efficiently focus photons on specific areas can be used to improve the photon capture by plant canopies. Our analysis demonstrates, however, that the cost per photon delivered is higher in these systems, regardless of fixture category. The lowest lighting system costs are realized when an efficient fixture is coupled with effective canopy photon capture.

  9. Reflected light intensity profile of two-layer tissues: phantom experiments.

    Science.gov (United States)

    Ankri, Rinat; Taitelbaum, Haim; Fixler, Dror

    2011-08-01

    Experimental measurements of the reflected light intensity from two-layer phantoms are presented. We report, for the first time, an experimental observation of a typical reflected light intensity behavior for the two-layer structure characterized by two different slopes in the reflected light profile of the irradiated tissue. The point in which the first slope changes to the second slope, named as the crossover point, depends on the upper layer thickness as well as on the ratio between the absorption coefficients of the two layers. Since similar experiments from one-layer phantoms present a monotonic decay behavior, the existence and the location of the crossover point can be used as a diagnostic fingerprint for two-layer tissue structures. This pertains to two layers with greater absorptivity in the upper layer, which is the typical biological case in tissues like skin.

  10. Image quality in double- and triple-intensity ghost imaging with classical partially polarized light

    CERN Document Server

    Kellock, Henri; Shirai, Tomohiro; Friberg, Ari T

    2012-01-01

    Classical ghost imaging is a correlation-imaging technique in which the image of the object is found through intensity correlations of light. We analyze three different quality parameters, namely the visibility, the signal-to-noise ratio (SNR), and the contrast-to-noise ratio (CNR), to assess the performance of double- and triple-intensity correlation-imaging setups. The source is a random partially polarized beam of light obeying Gaussian statistics and the image quality is evaluated as a function of the degree of polarization (DoP). We show that the visibility improves when the DoP and the order of imaging increase, while the SNR behaves oppositely. The CNR is for the most part independent of DoP and the imaging order. The results are important for the development of new imaging devices using partially polarized light.

  11. Universal sensitivity of speckle intensity correlations to wavefront change in light diffusers

    CERN Document Server

    Kim, KyungDuk; Lee, KyeoReh; Park, YongKeun

    2016-01-01

    Here, we present a concept based on the realization that a complex medium can be used as a simple interferometer. Changes in the wavefront of an incident coherent beam can be retrieved by analyzing changes in speckle patterns when the beam passes through a light diffuser. We demonstrate that the spatial intensity correlations of the speckle patterns are independent of the light diffusers, and are solely determined by the phase changes of an incident beam. With numerical simulations using the random matrix theory, and an experimental pressure-driven wavefront-deforming setup using a microfluidic channel, we theoretically and experimentally confirm the universal sensitivity of speckle intensity correlations, which is attributed to the conservation of optical field correlation despite multiple light scattering. This work demonstrates that a complex media is a simple interferometer, and presents opportunities to replace complicated reference-beam-assisted interferometers with a simple and compact scattering layer...

  12. Comparison of solar photospheric bright points between SUNRISE observations and MHD simulations

    CERN Document Server

    Riethmüller, T L; Berdyugina, S V; Schüssler, M; Pillet, V Mart\\'\\inez; Feller, A; Gandorfer, A; Hirzberger, J

    2014-01-01

    Bright points (BPs) in the solar photosphere are radiative signatures of magnetic elements described by slender flux tubes located in the darker intergranular lanes. They contribute to the ultraviolet (UV) flux variations over the solar cycle and hence may influence the Earth's climate. Here we combine high-resolution UV and spectro-polarimetric observations of BPs by the SUNRISE observatory with 3D radiation MHD simulations. Full spectral line syntheses are performed with the MHD data and a careful degradation is applied to take into account all relevant instrumental effects of the observations. It is demonstrated that the MHD simulations reproduce the measured distributions of intensity at multiple wavelengths, line-of-sight velocity, spectral line width, and polarization degree rather well. Furthermore, the properties of observed BPs are compared with synthetic ones. These match also relatively well, except that the observations display a tail of large and strongly polarized BPs not found in the simulation...

  13. High-frequency oscillations in small magnetic elements observed with Sunrise/SuFI

    CERN Document Server

    Jafarzadeh, Shahin; Stangalini, M; Steiner, O; Cameron, R H; Danilovic, S

    2016-01-01

    We characterize waves in small magnetic elements and investigate their propagation in the lower solar atmosphere from observations at high spatial and temporal resolution. We use the wavelet transform to analyze oscillations of both horizontal displacement and intensity in magnetic bright points found in the 300 nm and the Ca II H 396.8 nm passbands of the filter imager on board the Sunrise balloon-borne solar observatory. Phase differences between the oscillations at the two atmospheric layers corresponding to the two passbands reveal upward propagating waves at high-frequencies (up to 30 mHz). Weak signatures of standing as well as downward propagating waves are also obtained. Both compressible and incompressible (kink) waves are found in the small-scale magnetic features. The two types of waves have different, although overlapping, period distributions. Two independent estimates give a height difference of approximately 450+-100 km between the two atmospheric layers sampled by the employed spectral bands. ...

  14. Effects of Light Intensity and Color on the Biomass, Extracellular Red Pigment, and Citrinin Production of Monascus ruber.

    Science.gov (United States)

    Wang, Liling; Dai, Yang; Chen, Wanping; Shao, Yanchun; Chen, Fusheng

    2016-12-21

    Light is a crucial environmental signal for fungi. In this work, the effects of different light intensities and colors on biomass, Monascus pigments (MPs) and citrinin production of Monascus ruber M7 were investigated. We have demonstrated that low intensity of blue light (500 lx) decreased Monascus biomass, increased MPs accumulation via upregulation of MpigA, MpigB, and MpigJ genes expression, but had no significant influence on citrinin production. High intensity of blue light (1500 lx) decreased citrinin accumulation but had no significant influence on biomass and MPs production after 14 days cultivation. Low intensity of green light (500 lx) stimulated citrinin production via upregulation of pksCT, mrl1, mrl2, and ctnA genes expression. One putative red light photoreceptor and two putative green light photoreceptors were identified in M. ruber M7. These observations will not only guide the practical production of Monascus but also contribute to our understanding light effects on Monascus.

  15. Response to variable light intensity in photoacclimated algae and cyanobacteria exposed to atrazine

    Energy Technology Data Exchange (ETDEWEB)

    Deblois, Charles P.; Dufresne, Karine [Department of Biological Sciences-TOXEN, Ecotoxicology of Aquatic Microorganisms Laboratory, Universite du Quebec a Montreal, Succ. Centre-Ville, Montreal, Quebec (Canada); Juneau, Philippe, E-mail: juneau.philippe@uqam.ca [Department of Biological Sciences-TOXEN, Ecotoxicology of Aquatic Microorganisms Laboratory, Universite du Quebec a Montreal, Succ. Centre-Ville, Montreal, Quebec (Canada)

    2013-01-15

    Atrazine is frequently detected in freshwater ecosystems exposed to agricultural waste waters and runoffs worldwide and it can affect non-target organisms (mainly photoautotrophic) and modify community structure. Meanwhile, light environment is known to vary between aquatic ecosystems, but also before and during the exposure to atrazine and these variations may modify the sensitivity to atrazine of photoautotroph organisms. In this study, 10 species of phytoplankton (chlorophytes, baccilariophytes and cyanophytes) acclimated to low or high light intensities were exposed to atrazine and light of different intensities to compare their combined effect. Our data showed that chlorophytes and baccilariophytes were more resistant to atrazine compared to cyanophytes for all light conditions. Atrazine was found to inhibit {Phi}{sup Prime }{sub M}, {Psi}{sub 0}, P{sub M} and non-photochemical quenching for all species indicating an effect on electron transport, primary production and photoregulation processes. These data also indicate a higher sensitivity of {Psi}{sub 0} (average {Psi}{sub 0}-EC{sub 50} of 91 {+-} 11 nM or 19.6 {+-} 0.9 {mu}g L{sup -1}) compared to {Phi}{sup Prime }{sub M} (average {Phi}{sup Prime }{sub M}-EC{sub 50} of 217 {+-} 19 nM or 46.8 {+-} 4.1 {mu}g L{sup -1}) and suggest that photoregulation processes activated in presence of light decrease the effect of atrazine. We also showed that increasing light intensity decreased {Phi}{sup Prime }{sub M}-EC{sub 50} in both low (except baccilariophytes) and high light acclimated conditions. Despite this similarity, most species acclimated to high light were found to have higher or similar {Phi}{sup Prime }{sub M}-EC{sub 50} compared to low light acclimated cells and thus, were less sensitive to atrazine in low light and high light environments. We concluded that an increase in the plastoquinone pool induced by acclimation to high light decreased the sensitivity to atrazine in phytoplankton and we hypothesized

  16. Impact of light intensity on flowering time and plant quality of Antirrhinum majus L.cultivar Chimes White

    Institute of Scientific and Technical Information of China (English)

    MUNIR Muhammad; JAMIL Muhammad; BALOCH Jalal-ud-din; KHATTAK Khalid Rehman

    2004-01-01

    Shades of different light intensities (29%, 43%, 54%, 60% or 68%) along with control (no shade) were studied to observe their effects on the flowering time and plant quality. A hyperbolic relationship was observed between different light intensities under shade, and time to flowering. The total number of flower buds showed a curvilinear relationship with light intensities. Growth parameters related to the plant characteristics such as plant height, leaf area and plant fresh weight were improved under shading treatments at the expense of flowering time and number of flower buds. However, both linear and polynomial models applied assumed that cultivar Chimes White was equally sensitive to light intensity throughout development.

  17. Effects of light intensity and temperature on Cryptomonas ovata (Cryptophyceae) growth and nutrient uptake rates

    Science.gov (United States)

    Cloern, James E.

    1977-01-01

    Specific growth rate of Cryptomonas ovata var. palustris Pringsheim was measured in batch culture at 14 light-temperature combinations. Both the maximum growth rate (μm) and optimum light intensity (Iopt) fit an empirical function that increases exponentially with temperature up to an optimum (Topt), then declines rapidly as temperature exceeds Topt. Incorporation of these functions into Steele's growth equation gives a good estimate of specific growth rate over a wide range of temperature and light intensity. Rates of phosphate, ammonium and nitrate uptake were measured separately at 16 combinations of irradiance and temperature and following a spike addition of all starved cells initially took up nutrient at a rapid rate. This transitory surge was followed by a period of steady, substrate-saturated uptake that persisted until external nutrient concentration fell. Substrate-saturated NO3−-uptake proceeded at very slow rates in the dark and was stimulated by both increased temperature and irradiance; NH4+-uptake apparently proceeded at a basal rate at 8 and l4 C and was also stimulated by increased temperature and irradiance. Rates of NH4−-uptake were much higher than NO3−-uptake at all light-temperature combinations. Below 20 C, PO4−3-uptake was more rapid in dark than in light, but was light enhanced at 26 C.

  18. Improvement of photosynthetic CO2 fixation at high light intensity through reduction of chlorophyll antenna size.

    Science.gov (United States)

    Lee, James W; Mets, Laurens; Greenbau, Elias

    2002-01-01

    At elevated light intensities (greater than approximately 200 microE/[m2 x s]), the kinetic imbalance between the rate of photon excitation and thermally activated electron transport results in saturation of the rate of photosynthesis. Since maximum terrestrial solar radiation can reach 200 microE/(m2 x s), a significant opportunity exists to improve photosynthetic efficiency at elevated light intensities by achieving a kinetic balance between photon excitation and electron transport, especially in designed large-scale photosynthetic reactors in which a low-cost and efficient biomass production system is desired. One such strategy is a reduction in chlorophyll (chl) antenna size in relation to the reaction center that it serves. In this article, we report recent progress in this area of research. Light-saturation studies for CO2 fixation were performed on an antenna-deficient mutant of Chlamydomonas (DS521) and the wild type (DES15) with 700 ppm of CO2 in air. The light-saturated rate for CO2 assimilation in the mutant DS521 was about two times higher (187 micromol/[h x mg of chl]) than that of the wild type, DES15 (95 micromol/[h x mg of chl]). Significantly, a partial linearization of the light-saturation curve was also observed. These results confirmed that DS521 has a smaller relative chl antenna size and demonstrated that reduction of relative antenna size can improve the overall efficiency of photon utilization at higher light intensities. The antenna-deficient mutant DS521 can provide significant resistance to photoinhibition, in addition to improvement in the overall efficiency of CO2 fixation at high light. The experimental data reported herein support the idea that reduction in chl antenna size could have significant implications for both fundamental understanding of photosynthesis and potential application to improve photosynthetic CO2 fixation efficiency.

  19. [Effects of light intensity on Quercus liaotungensis seed germination and seedling growth].

    Science.gov (United States)

    Yan, Xing-fu; Wang, Jian-li; Zhou, Li-biao

    2011-07-01

    This paper studied the effects of different shading (55.4%, 18.9%, 5.5%, 2.2%, 0.5% , and 0.3% natural sunlight) on the seed germination and seedling growth of Quercus liaotungensis. The seed germination rate and germination index were the highest (72.5% and 0.22, respectively) at 55.4% natural sunlight, declined with decreasing light intensity, and were the lowest (42.5% and 0.11, respectively) at 0.3% natural sunlight. Strong light had definite delaying effect on the germination. The index of germination vigor increased with decreasing light intensity, being the maximum at 0.5% natural sunlight. The delay of seed germination under strong light could be the selective tradeoff on varied seed fates. Strong light benefited the basal stem diameter and root system growth and dry mass accumulation of Q. liaotunensis seedling, but resulted in the minimum seedlings height (6.06 cm). Greater morphological plasticity was observed for the seedlings under different shading, which lent support to the higher adaptability of the seedlings to light environment. For example, the specific leaf area, specific shoot length, specific root length, and chlorophyll b and total chlorophyll contents were the maximum at 0.5% natural sunlight, being 142.57 cm2 x g(-1), 156.86 cm x g(-1), 271.87 cm x g(-1), 0.07 g x cm(-2), and 0.24 g x cm(-2), respectively, and the minimum at 55.4% natural sunlight, being 44.89 cm2 x g(-1), 52.84 cm x g(-1), 101.98 cm x g(-1), 0.04 g x cm(-2), and 0.15 g x cm(-2), respectively. The variation of the root/shoot ratio of Q. liaotungensis seedlings under different shading could be the effects of the combination of light intensity and water availability.

  20. Is light deflected by light ? A proposal to observe a vacuum refractive index gradient induced by intense laser pulses

    CERN Document Server

    Couchot, F; Guilbaud, O; Kazamias, S; Pittman, M; Sarazin, X; Urban, M

    2016-01-01

    In very intense electromagnetic fields, the vacuum refractive index is expected to be modified due to non linear QED properties. Up to now, these predictions are tested by searching phase shifts in the propagation of polarized light through uniform magnetic fields. We propose a new approach which consists in producing a vacuum index gradient and send a light beam trough it in order to detect its angular deviation. The vacuum index gradient, similar to a "prismatic vacuum", is created by the interaction of two very intense and ultra short laser pulses, used as pump pulses. At the maximum of the index gradient, the deflection angle of the probe pulse is estimated to be $2 \\ 10^{-13} \\times (\\frac{w_0}{10 \\mu\\mathrm{m}})^{-3} \\times \\frac{I}{1 \\mathrm{J}}$ radians, where $I$ is the total energy of the two pump pulses and $w_0$ is the minimum waist (fwhm) at the interaction area of the two pump pulses. Assuming the most intense laser pulses attainable by the LASERIX facility ($I = 25$ J, 30 fs fwhm duration, 800 ...

  1. Influence of green, red and blue light emitting diodes on multiprotein complex proteins and photosynthetic activity under different light intensities in lettuce leaves (Lactuca sativa L.).

    Science.gov (United States)

    Muneer, Sowbiya; Kim, Eun Jeong; Park, Jeong Suk; Lee, Jeong Hyun

    2014-03-17

    The objective of this study was to investigate the response of light emitting diodes (LEDs) at different light intensities (70 and 80 for green LEDs, 88 and 238 for red LEDs and 80 and 238 μmol m-2 s-1 for blue LEDs) at three wavelengths in lettuce leaves. Lettuce leaves were exposed to (522 nm), red (639 nm) and blue (470 nm) LEDs of different light intensities. Thylakoid multiprotein complex proteins and photosynthetic metabolism were then investigated. Biomass and photosynthetic parameters increased with an increasing light intensity under blue LED illumination and decreased when illuminated with red and green LEDs with decreased light intensity. The expression of multiprotein complex proteins including PSII-core dimer and PSII-core monomer using blue LEDs illumination was higher at higher light intensity (238 μmol m-2 s-1) and was lowered with decreased light intensity (70-80 μmol m-2 s-1). The responses of chloroplast sub-compartment proteins, including those active in stomatal opening and closing, and leaf physiological responses at different light intensities, indicated induced growth enhancement upon illumination with blue LEDs. High intensity blue LEDs promote plant growth by controlling the integrity of chloroplast proteins that optimize photosynthetic performance in the natural environment.

  2. The effects of light intensity on the growth of Japanese Gambierdiscus spp. (Dinophyceae).

    Science.gov (United States)

    Yoshimatsu, Takamichi; Tie, Chaoyu; Yamaguchi, Haruo; Funaki, Hiroshi; Honma, Chiho; Tanaka, Kouki; Adachi, Masao

    2016-12-01

    Marine toxic dinoflagellates of the genus Gambierdiscus are the causative agents of ciguatera fish poisoning (CFP), a form of seafood poisoning that is widespread in tropical, subtropical and temperate regions worldwide. The distributions of Gambierdiscus australes, Gambierdiscus scabrosus and two phylotypes of Gambierdiscus spp. type 2 and type 3 have been reported for the waters surrounding the main island of Japan. To explore the bloom dynamics and the vertical distribution of these Japanese species and phylotypes of Gambierdiscus, the effects of light intensity on their growth were tested, using a photoirradiation-culture system. The relationship between the observed growth rates and light intensity conditions for the four species/phylotypes were formulated at R>0.92 (p<0.01) using regression analysis and photosynthesis-light intensity (P-L) model. Based on this equation, the optimum light intensity (Lmax) and the semi-optimum light intensity range (Ls-opt) that resulted in the maximum growth rate (μmax) and ≥80% μmax values of the four species/phylotypes, respectively, were as follows: (1) the Lmax and Ls-opt of G. australes were 208μmol photons m(-2)s(-1) and 91-422μmol photons m(-2)s(-1), respectively; (2) those of G. scabrosus were 252 and 120-421μmol photons m(-2)s(-1), respectively; (3) those of Gambierdiscus sp. type 2 were 192 and 75-430μmol photons m(-2)s(-1), respectively; and (4) those of Gambierdiscus sp. type 3 were ≥427 and 73-427μmol photons m(-2)s(-1), respectively. All four Gambierdiscus species/phylotypes required approximately 10μmol photons m(-2)s(-1) to maintain growth. The light intensities in coastal waters at a site in Tosa Bay were measured vertically at 1m intervals once per season. The relationships between the observed light intensity and depth were formulated using Beer's Law. Based on these equations, the range of the attenuation coefficients at Tosa Bay site was determined to be 0.058-0.119m(-1). The values 1700

  3. Sunrise coal, an innovative New Indiana player continues to grow

    Energy Technology Data Exchange (ETDEWEB)

    Buchsbaum, L.

    2009-07-15

    Sunrise Coal LLC's Carliste (Indiana) underground mine began development in 2006. Today, the room and pillar operation has grown to a 3 million tpy four unit continuous miner mine. Its coal has low (0.06%) chlorine level and is now being purchased to blend down high chlorine in Illinois Basin coal. The article describes the mining operation and equipment traces the growth of the company, founded in the 1970s by Row and Steve Laswell, emphasizing its focus on employee safety. 5 photos.

  4. Study on the backscattered light intensity to airborne laser range-gated imaging

    Science.gov (United States)

    Wang, Ling; Yu, Lei; Kou, Tian; Wu, Xueming

    2016-10-01

    Based on the range-gated technology in the application of airborne laser detection imaging system, sequence relations of the parameters in the model of range gating in detail was analyzed. The effective scope of atmospheric backscatter and the moment before or after pulsing of the unit section was obtained. Horizontal range-gated imaging model was established and the calculation method of backscattered light intensity was given. Then slant distance detection of airborne laser active imaging was revised. By the object-image relation of points on the scattering section, the light path diagram of imaging detection system was built and the corresponding relation of light intensity between scattering points and receiving points was given. The variation regularity and distribution of light intensity on the detector under horizontal and slant detection were gained. Under the idea, the outfield testing platform was set up, and the relative error of data between measured and simulated results was controlled within 5%. The two kinds of data achieved a good coincident, which demonstrated the effectiveness of the built model. The two kinds of data achieved a good coincident, which demonstrated the effectiveness of the built model.

  5. Continuous cultures of spirulina platensis under photoautotrophic conditions with change in light intensity

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, S. [Osaka Univ., Suita (Japan)532600; Taya, M.; Tone, S. [Kawasaki Heavy Industries Ltd., Kobe (Japan)

    1998-08-01

    In continuous cultures of Spirulina platensis under photoautotrophic conditions, the operation mode to maintain constant cell concentration is examined using culture apparatuses with light path lengths of 0.02 and 0.156 m. The values of dilution rates in the continuous cultures are determined by employing specific growth rates of the cells corresponding to light intensity distribution in liquid medium. When incident light intensity is fixed at 25, 50 or 400 W m{sup minus2}, it is found that the cell concentration in the continuous culture is kept almost constant, and agrees fairly well with the prescribed value of the cell concentration in the range of 0.09 to 2.43 kg m{sup minus3}. It is also demonstrated that the operation mode is valid to obtain stable cell concentrations in the continuous cultures associated with the change in incident light intensity ranging from 25 to 400 W m{sup minus2} during the cultures. 7 refs., 3 figs., 1 tabs.

  6. Effects of soil moisture and light intensity on ecophysiological characteristics of Amorpha fruticosa seedlings

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiu-ru; TAN Xiang-feng; WANG Ren-qing; XU Nan-nan; GUO Wei-hua

    2013-01-01

    We investigated the combined effects of soil moisture and light intensity on the growth,development and ecophysiological characteristics of one-year old Amorpha fruticosa seedlings.Soil moisture and light intensity influenced the ecophysiological characteristics of Amorphafruticosa seedlings.Soil moisture resulted in the decreases of growth rate,individual size,net photosynthetic rate,transpiration rate,leaf water loss rate (WLR),and biomass accumulation of plant parts,and led to increased leaf water saturation deficit (WSD).Under water stress,more photosynthetic products were allocated to root growth.With decreasing light intensity,net photosynthetic rate,transpiration rate,chla/b,water saturation deficit,water use efficiency,water loss rate and biomass accumulation declined,while Chla,Chlb,Chla+b and carotenoids (Car)increased and more photosynthetic products were allocated to stem and leaf growth.Maximum growth vigor,net photosynthetic rate and total biomass accumulation in Amorpha fruticosa seedlings was recorded at 75-80% soil water-holding capacity and 100% light density in greenhouse environments.

  7. Effects of light intensity of photosynthesis and dark respiration in six species of marine phytoplankton

    Energy Technology Data Exchange (ETDEWEB)

    Falkowski, P.G.; Owens, T.G.

    1978-01-01

    Using an oxygen polarographic electrode, the shapes of photosynthetic curves and the effects of light on dark respiration in 6 species of marine phytoplankton were examined. The species used were Skeletonema costatum, Ditylum brightwellii, Cyclotella nana (Thalassiosira pseudonana) (all Bacillariophyceae), Dunaliella tertiolecta (Chlorophyceae), Isochrysis galbana (Haptophyceae), and Gonyaulax tamarensis (Dinophyceae). A hysteresis was observed in all species examined with respect to increasing and decreasing light. Compensation light intensities varied by over 4 orders of magnitude, suggesting that the 1% light depth is an ambiguous measure of the euphotic zone. The data suggest that dark respiration accounts for ca. 25% of gross photosynthesis, but is species-dependent. In addition, respiration versus cell size does not describe an inverse exponential function over the size scales examined.

  8. Antioxidant capacity reduced in scallions grown under elevated CO 2 independent of assayed light intensity

    Science.gov (United States)

    Levine, Lanfang H.; Paré, Paul W.

    2009-10-01

    Long-duration manned space missions mandate the development of a sustainable life support system and effective countermeasures against damaging space radiation. To mitigate the risk of inevitable exposure to space radiation, cultivation of fresh fruits and vegetables rich in antioxidants is an attractive alternative to pharmacological agents. However it has yet to be established whether antioxidant properties of crops can be preserved or enhanced in a space environment where environmental conditions differ from that which plants have acclimated to on earth. Scallion ( Allium fistulosum) rich in antioxidant vitamins C and A, and flavonoids was used as a model plant to study the impact of a range of CO 2 concentrations and light intensities that are likely encountered in a space habitat on food quality traits. Scallions were hydroponically grown in controlled environmental chambers under a combination of 3 CO 2 concentrations of 400, 1200 and 4000 μmol mol -1 and 3 light intensity levels of 150, 300, 450 μmol m -2 s -1. Total antioxidant activity (TAA) of scallion extracts was determined using a radical cation scavenging assay. Both elevated CO 2 and increasing light intensity enhanced biomass accumulation, but effects on TAA (based on dry weight) differed. TAA was reduced for plants grown under elevated CO 2, but remained unchanged with increases in light intensity. Elevated CO 2 stimulated greater biomass production than antioxidants, while an increase in photosynthetic photo flux promoted the synthesis of antioxidant compounds at a rate similar to that of biomass. Consequently light is a more effective stimulus than CO 2 for antioxidant production.

  9. Development of terminal hair following skin lesion treatments with an intense pulsed light source.

    Science.gov (United States)

    Vlachos, Spiros P; Kontoes, Paraskevas P

    2002-01-01

    Laser and other light sources have been used to treat vascular and pigmented skin lesions and to remove tattoos and unwanted hair, with varying degrees of success and various side effects. It has not yet been reported that hair growth can occur as a side effect of such treatments. In this paper two cases are presented, one port wine stain and one tattoo, that were each treated several times with an intense pulsed light source (IPLS) for removal. Terminal hair, not present before treatment, partially developed in treated areas of both lesions. Local inflammatory reactions are believed to trigger such outcomes.

  10. Relationship between caffeine content and flavor with light intensity of several coffee Robusta clones

    Directory of Open Access Journals (Sweden)

    Novie Pranata Erdiansyah

    2012-05-01

    Full Text Available Coffee is a refreshing beverage product and its price is determined by physical quality and flavor. An excellent coffee flavor is resulted only from qualified coffee beans, produced by well managed plantation. The objective of this experiment was to study the effect of sunlight intensity entering coffee farm on flavor profiles and caffeine content of Robusta coffee. The experiment was conducted at the field experimental Kaliwining Estate of Indonesian Coffee and Cocoa Research Institute (ICCRI during 2009–2011. Treatments were Robusta coffee clones and sunlight intensity. Experimental design was split plot design with three replications. Robusta clones used were BP 409, BP 534, BP 936 and BP 939, planted in 2002. The sunligt intensity treatments were 100% (without shade tree, 50—60% (Leucaena leucocephala shade, and 20—30% (Hibiscus macrophyllus and Melia azedarach L. shades. Only red coffee cherries were harvested for flavor and caffeine analysis. Coffee cherries were washed, depulped and sundried until moisture content of less than 12%. The green coffee bean samples were roasted at medium level (Agtron Scale at 65# for cupping test which involved five expert panelists by using ICCRI protocol. Caffeine content was determined by spectrophotometric method. The experiment result indicated that high sunlight intensity resulted in strong aroma of Robusta coffee, while good flavor coffee need medium light intensity. Cafein content had positive correlation with light intensity entering the coffee farm, whereas cafein content had no direct effect on Robusta coffee flavor.Key words: Coffea canephora, clone, sunlight intensity, flavor, caffeine. 

  11. A coordinate transformation method for calculating the 3D light intensity distribution in ICF hohlraum

    Science.gov (United States)

    Lin, Zhili; Li, Xiaoyan; Zhao, Kuixia; Chen, Xudong; Chen, Mingyu; Pu, Jixiong

    2016-06-01

    For an inertial confinement fusion (ICF) system, the light intensity distribution in the hohlraum is key to the initial plasma excitation and later laser-plasma interaction process. Based on the concept of coordinate transformation of spatial points and vector, we present a robust method with a detailed procedure that makes the calculation of the three dimensional (3D) light intensity distribution in hohlraum easily. The method is intuitive but powerful enough to solve the complex cases of random number of laser beams with arbitrary polarization states and incidence angles. Its application is exemplified in the Shenguang III Facility (SG-III) that verifies its effectiveness and it is useful for guiding the design of hohlraum structure parameter.

  12. A comparative study of hair removal at an NHS hospital: Luminette intense pulsed light versus electrolysis.

    Science.gov (United States)

    Harris, Karen; Ferguson, Janice; Hills, Samantha

    2014-04-01

    Twenty-five women, referred for hair removal by electrolysis, were enrolled in a split face study to treat facial hirsutism. Each patient was treated on six occasions: one-half of the face with electrolysis and the other side with an intense pulsed light source. Patients were evaluated with respect to reduction in hair counts, side effects and discomfort during treatment. Re-growth was assessed at 3, 6 and 9 months following treatment. All patients, except one with very sparse, fair hair growth, preferred treatment with the Intense Pulsed Light and rated their average hair reduction with this method as 77% after five treatments. The overall patient satisfaction rates as determined by visual analogue scales were 8.3 out of 10 for IPL and 5.4 out of 10 for electrolysis.

  13. Chronic neuropathic facial pain after intense pulsed light hair removal. Clinical features and pharmacological management

    Science.gov (United States)

    Párraga-Manzol, Gabriela; Sánchez-Torres, Alba; Moreno-Arias, Gerardo

    2015-01-01

    Intense Pulsed Light (IPL) photodepilation is usually performed as a hair removal method. The treatment is recommended to be indicated by a physician, depending on each patient and on its characteristics. However, the use of laser devices by medical laypersons is frequent and it can suppose a risk of damage for the patients. Most side effects associated to IPL photodepilation are transient, minimal and disappear without sequelae. However, permanent side effects can occur. Some of the complications are laser related but many of them are caused by an operator error or mismanagement. In this work, we report a clinical case of a patient that developed a chronic neuropathic facial pain following IPL hair removal for unwanted hair in the upper lip. The specific diagnosis was painful post-traumatic trigeminal neuropathy, reference 13.1.2.3 according to the International Headache Society (IHS). Key words:Neuropathic facial pain, photodepilation, intense pulse light. PMID:26535105

  14. A single molecule as a high-fidelity photon gun for producing intensity-squeezed light

    Science.gov (United States)

    Chu, Xiao-Liu; Götzinger, Stephan; Sandoghdar, Vahid

    2017-01-01

    A two-level atom cannot emit more than one photon at a time. As early as the 1980s, this quantum feature was identified as a gateway to 'single-photon sources', where a regular excitation sequence would create a stream of light particles with photon number fluctuations below the shot noise. Such an intensity-squeezed beam of light would be desirable for a range of applications, such as quantum imaging, sensing, enhanced precision measurements and information processing. However, experimental realizations of these sources have been hindered by large losses caused by low photon-collection efficiencies and photophysical shortcomings. By using a planar metallodielectric antenna applied to an organic molecule, we demonstrate the most regular stream of single photons reported to date. The measured intensity fluctuations were limited by our detection efficiency and amounted to 2.2 dB squeezing.

  15. Measuring acoustic energy density in microchannel acoustophoresis using a simple and rapid light-intensity method

    DEFF Research Database (Denmark)

    Barnkob, Rune; Iranmanesh, Ida; Wiklund, Martin;

    2012-01-01

    We present a simple and rapid method for measuring the acoustic energy density in microchannel acoustophoresis based on light-intensity measurements of a suspension of particles. The method relies on the assumption that each particle in the suspension undergoes single-particle acoustophoresis....... It is validated by the single-particle tracking method, and we show by proper re-scaling that the re-scaled light intensity plotted versus re-scaled time falls on a universal curve. The method allows for analysis of moderate-resolution images in the concentration range encountered in typical experiments......, and it is an attractive alternative to particle tracking and particle image velocimetry for quantifying acoustophoretic performance in microchannels....

  16. The use of lasers and intense pulsed light sources for the treatment of pigmentary lesions.

    Science.gov (United States)

    Chan, H H L; Kono, T

    2004-10-01

    Lasers and intense pulsed light sources are frequently used for the treatment of pigmented lesions, and the appropriate selection of devices for different lesions is vital to achieving satisfactory clinical outcomes. In dark-skinned patients, the risk of post-inflammatory hyperpigmentation is of particular importance. In general, long-pulse laser and intense pulsed light sources can be effective with a low risk of post-inflammatory hyperpigmentation (PIH) when used for the treatment of lentigines. However, for dermal pigmentation and tattoo, Q-switched lasers are effective, with a lower risk of complications. In the removal of melanocytic nevi, a combined approach with a long-pulse pigmented laser and a Q-switched laser is particularly applicable.

  17. Long-pulsed dye laser vs. intense pulsed light for the treatment of facial telangiectasias: a randomized controlled trial

    DEFF Research Database (Denmark)

    Nymann, Peter; Hedelund, Lene; Haedersdal, M

    2010-01-01

    This study aims to compare the efficacy and adverse effects of long-pulsed dye laser (LPDL) and intense pulsed light (IPL) in the treatment of facial telangiectasias.......This study aims to compare the efficacy and adverse effects of long-pulsed dye laser (LPDL) and intense pulsed light (IPL) in the treatment of facial telangiectasias....

  18. Simultaneous Effects of Light Intensity and Phosphorus Supply on the Sterol Content of Phytoplankton

    OpenAIRE

    Maike Piepho; Dominik Martin-Creuzburg; Alexander Wacker

    2010-01-01

    Sterol profiles of microalgae and their change with environmental conditions are of great interest in ecological food web research and taxonomic studies alike. Here, we investigated effects of light intensity and phosphorus supply on the sterol content of phytoplankton and assessed potential interactive effects of these important environmental factors on the sterol composition of algae. We identified sterol contents of four common phytoplankton genera, Scenedesmus, Chlamydomonas, Cryptomonas ...

  19. Effect of oxygen at low and high light intensities on the growth of Neochloris oleoabundans

    NARCIS (Netherlands)

    Sousa, C.A.; Compadre, A.; Vermuë, M.H.; Wijffels, R.H.

    2013-01-01

    The effect of partial oxygen pressure on growth of Neochloris oleoabundans was studied at near-saturating light intensity in a fully-controlled photobioreactor. At the partial oxygen pressures tested (PO2=0.24; 0.42; 0.63; 0.84 bar), the specific growth rate was 1.36; 1.16; 0.93 and 0.68 day-1,

  20. Effect of oxygen at low and high light intensities on the growth of Neochloris oleoabundans

    NARCIS (Netherlands)

    Sousa, C.A.; Compadre, A.; Vermuë, M.H.; Wijffels, R.H.

    2013-01-01

    The effect of partial oxygen pressure on growth of Neochloris oleoabundans was studied at near-saturating light intensity in a fully-controlled photobioreactor. At the partial oxygen pressures tested (PO2=0.24; 0.42; 0.63; 0.84 bar), the specific growth rate was 1.36; 1.16; 0.93 and 0.68 day-1, resp

  1. Sedentary behaviors and light-intensity activities in relation to colorectal cancer risk.

    Science.gov (United States)

    Keum, NaNa; Cao, Yin; Oh, Hannah; Smith-Warner, Stephanie A; Orav, John; Wu, Kana; Fuchs, Charles S; Cho, Eunyoung; Giovannucci, Edward L

    2016-05-01

    A recent meta-analysis found that sedentary behaviors are associated with an increased colorectal cancer (CRC) risk. Yet, the finding on TV viewing time, the most widely used surrogate of sedentary behaviors, was based on only two studies. Furthermore, light-intensity activities (e.g., standing and slow walking), non-sedentary by posture but close to sedentary behaviors by Metabolic Equivalent Task values, have not been investigated in relation to CRC risk. Thus, we prospectively analyzed the relationships based on 69,715 women from Nurses' Health Study (1992-2010) and 36,806 men from Health Professionals Follow-Up Study (1988 - 2010). Throughout follow-up, time spent on sedentary behaviors including sitting watching TV and on light-intensity activities were assessed repeatedly; incidence of CRC was ascertained. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models from each cohort. A total of 1,119 and 913 incident cases were documented from women and men, respectively. The multivariable HR comparing ≥ 21 versus sedentary and physically less active had an approximately 41% elevated risk of CRC (95% CI = 1.03 to 1.92) compared with those less sedentary and physically more active. The other sedentary behaviors and light-intensity activities were not related to CRC risk in women or men. In conclusion, we found that prolonged sitting time watching TV was associated with an increased CRC risk in women but not in men.

  2. Effect of Light Intensity and Photoperiod on Growth and Biochemical Composition of a Local Isolate of Nostoc calcicola.

    Science.gov (United States)

    Khajepour, Fateme; Hosseini, Seyed Abbas; Ghorbani Nasrabadi, Rasoul; Markou, Giorgos

    2015-08-01

    A study was conducted to investigate the effect of light intensity (21, 42, and 63 μmol photons m(-2) s(-1)) and photoperiod (8:16, 12:12, and 16:8 h light/dark) on the biomass production and its biochemical composition (total carotenoids, chlorophyll a, phycoerythrin (PE), phycocyanin (PC) and allophycocyanin (APC), total protein, and carbohydrates) of a local isolate of Nostoc calcicola. The results revealed that N. calcicola prefers dim light; however, the most of the levels of light intensity and photoperiod investigated did not have a significant impact on biomass production. Increasing light intensity biomass content of chlorophyll a, PE, PC, APC, and total protein decreased, while total carotenoids and carbohydrate increased. The same behavior was observed also when light duration (photoperiod) increased. The interaction effect of increasing light intensity and photoperiod resulted in an increase of carbohydrate and total carotenoids, and to the decrease of chlorophyll a, PE, PC, APC, and total protein content. The results indicate that varying the light regime, it is capable to manipulate the biochemical composition of the local isolate of N. calcicola, producing either valuable phycobiliproteins or proteins under low light intensity and shorter photoperiods, or producing carbohydrates and carotenoids under higher light intensities and longer photoperiods.

  3. INDUCTION OF ANTIMICROBIAL ACTIVITY OF SOME MACROMYCETES BY LOW-INTENSITY LIGHT

    Directory of Open Access Journals (Sweden)

    N. L. Poyedinok

    2015-02-01

    Full Text Available The aim of the work was to study the induction of antimicrobial activity of macromycetes by low-intensity light of different wavelengths and coherence. The objects of investigation were the strains of Flammulina velutipes 3923, Pleurotus ostreatus 531, Ganoderma lucidum 1908 and G. applanatum 1552 from Mushrooms Collection of the Kholodny Institute of Botany of the National Academy of Sciences of Ukraine, the test-cultures from Cultural Collections of the Gause Institute of New Antibiotics, All-Union Research Institute of Antibiotics and the All-Russian Collection of Industrial microorganisms. Helium-neon laser with a wavelength of 632.8 nm and an argon ion laser with wavelengths of 488.0 nm and 514.5 nm were used as a source of coherent visible light lasers. For obtaining incoherent light LEDs with emission at a wavelength of 490.0, 520.0 and 634.0 nm were used. It was found that short-term exposure of sowing mycelium by low intensity light with the energy density of 230 MJ/cm2 in the red and blue wavelength ranges reduced the cultivation period before the appearance of antimicrobial activity and induced the increasing of the culture fluid inhibitory activity against different test-cultures from 20 to 238%. Selected modes of antimicrobial activity photostimulation could be used in biotechnology of submerged cultivation of macromycetes for intensification of technological stages and increasing the yield of the final product.

  4. Influence of the excitation light intensity on the rate of fluorescence quenching reactions: pulsed experiments.

    Science.gov (United States)

    Angulo, Gonzalo; Milkiewicz, Jadwiga; Kattnig, Daniel; Nejbauer, Michał; Stepanenko, Yuriy; Szczepanek, Jan; Radzewicz, Czesław; Wnuk, Paweł; Grampp, Günter

    2017-02-22

    The effect of multiple light excitation events on bimolecular photo-induced electron transfer reactions in liquid solution is studied experimentally. It is found that the decay of fluorescence can be up to 25% faster if a second photon is absorbed after a first cycle of quenching and recombination. A theoretical model is presented which ascribes this effect to the enrichment of the concentration of quenchers in the immediate vicinity of fluorophores that have been previously excited. Despite its simplicity, the model delivers a qualitative agreement with the observed experimental trends. The original theory by Burshtein and Igoshin (J. Chem. Phys., 2000, 112, 10930-10940) was created for continuous light excitation though. A qualitative extrapolation from the here presented pulse experiments to the continuous excitation conditions lead us to conclude that in the latter the order of magnitude of the increase of the quenching efficiency upon increasing the light intensity of excitation, must also be on the order of tens of percent. These results mean that the rate constant for photo-induced bimolecular reactions depends not only on the usual known factors, such as temperature, viscosity and other properties of the medium, but also on the intensity of the excitation light.

  5. Computer analysis of environmental temperature, light and noise in intensive care: chaos or chronome nurseries?

    Science.gov (United States)

    Ardura, J; Andrés, J; Aldana, J; Revilla, M A; Cornélissen, G; Halberg, F

    1997-09-01

    Lighting, noise and temperature were monitored in two perinatal nurseries. Rhythms of several frequencies were found, including prominent 24-hour rhythms with acrophases around 13:00 (light intensity) and 16:00 (noise). For light and noise, the ratio formed by dividing the amplitude of a 1-week (circaseptan) or half-week (circasemiseptan) fitted cosine curve by the amplitude of a 24-hour fitted cosine curve is smaller than unity, since 24-hour rhythms are prominent for these variables. The amplitude ratios are larger than unity for temperature in the newborns' unit but not in the infants' unit. Earlier, the origin of the about-7-day rhythms of neonatal physiologic variables was demonstrated to have, in addition to a major endogenous, also a minor exogenous component. Hence, the possibility of optimizing maturation by manipulating environmental changes can be considered, using, as gauges of development, previously mapped chronomes (time structures of biologic multifrequency rhythms, trends and noise).

  6. Effect of photoperiod, light intensity and carbon sources on biomass and lipid productivities of Isochrysis galbana.

    Science.gov (United States)

    Babuskin, Srinivasan; Radhakrishnan, Kesavan; Babu, Packirisamy Azhagu Saravana; Sivarajan, Meenakshisundaram; Sukumar, Muthusamy

    2014-08-01

    Biomass and lipid productivities of Isochrysis galbana were optimized using nutrients of molasses (4, 8, 12 g l(-1)), glucose (4, 8, 12 g l(-1)), glycerol (4, 8, 12 g l(-1)) and yeast extract (2 g l(-1)). Combinations of carbon sources at different ratios were evaluated in which the alga was grown at three different light intensities (50, 100 and 150 μmol m(-2) s(-1)) under the influence of three different photoperiod cycles (12/12, 18/6 and 24/0 h light/dark). A maximum cell density of 8.35 g l(-1) with 32 % (w/w) lipid was achieved for mixotrophic growth at 100 μmol m(-2) s(-1) and 18/6 h light/dark with molasses/glucose (20:80 w/w). Mixotrophic cultivation using molasses, glucose and glycerol was thus effective for the cultivation of I. galbana.

  7. The effect of intense light pulses on the sensory quality and instrumental color of meat from different animal breeds

    OpenAIRE

    Tomašević I.

    2015-01-01

    Intense light pulses (ILP) are an emerging processing technology, which has a potential to decontaminate food products. The light generated by ILP lamps consists of a continuum broadband spectrum from deep UV to the infrared, especially rich in UV range below 400 nm, which is germicidal. Evaluation of the effect of intense light pulses (ILP) on sensory quality of meat, game and poultry was performed using two kinds of red meat (beef and pork), two kinds of ...

  8. Effects of Light Intensity on the Growth, Photosynthetic Characteristics, and Flavonoid Content of Epimedium pseudowushanense B.L.Guo

    Directory of Open Access Journals (Sweden)

    Junqian Pan

    2016-11-01

    Full Text Available Epimedium pseudowushanense B.L.Guo is used in traditional medicine as an aphrodisiac and to strengthen muscles and bones. Several recent reports have shown that flavonoids from Epimedium also significantly affect the treatment of breast cancer, liver cancer, and leukemia. However, few studies have examined the medicinal-ingredient yield of Epimedium, a light-demanding shade herb, under different light intensities. To investigate the effects of light intensity on medicinal-ingredient yields, Epimedium was exposed to five levels of light intensity until harvest time. Leaf dry biomass under L4 was the highest among different light treatments. L4 was also associated with the highest net photosynthetic rate. Quantification of epimedin A, epimedin B, epimedin C, and icariin showed that L3 produced the highest amount of epimedin C, and that flavonoid content responded to light levels differently. Results indicated that L3 and L4 were the optimal light levels for medicinal-ingredient yield.

  9. The efficiency, energy intensity and visual impact of the accent lighting in the retail grocery stores

    Directory of Open Access Journals (Sweden)

    Ľudmila Nagyová

    2014-11-01

    Full Text Available Over the last few years, topics of displaying, presentation, lighting, energy saving and issues related to the environment while selling the fresh food (fruits, vegetable, bakery products, meat are becoming an important matter among traders. However, just bigger companies with transnational capital have devoted their attention to this issue yet. Generally, the energy costs make up 70% of operating costs in retail stores where the cooling system and lighting are the most energy consuming. Accent lighting in modern retails is largely involved in the overall design and atmosphere in shops and plays a crucial role in presenting the goods as well. Using of accent lighting can draw the customer's attention to a specific part of the sales area and achieve the overall harmonization in the store. With the rational using of combination of energy saving and effective accent lighting retailers can achieve not only attractive presentation of displayed products but also appreciable savings in the operation of their stores. It is the only factor that can be exactly measured and controlled. Using a Colour and Lux Meters we found out the intensity and color temperature of accent lighting used in domestic and foreign retail chains for the different kinds of fresh food products. Based on the obtained values we have compiled graphs, which are showing visual comfort. We also identified different types of accent lighting, which we assigned to their impact on emotional involvement of consumers. The starting points were the tests we conducted in simulated laboratory conditions. While searching of a compromise between effective and energy efficient accent lighting we take into consideration consumers' emotional response as well as the annual electricity consumption of different types of light sources. At the end we recommend options for energy-efficient, effective and spectacular lighting while using the optimal number of light sources and their logical organization

  10. Long lifetime, low intensity light source for use in nighttime viewing of equipment maps and other writings

    Science.gov (United States)

    Frank, Alan M.; Edwards, William R.

    1983-01-01

    A long-lifetime light source with sufficiently low intensity to be used for reading a map or other writing at nighttime, while not obscuring the user's normal night vision. This light source includes a diode electrically connected in series with a small power source and a lens properly positioned to focus at least a portion of the light produced by the diode.

  11. Intensity-dependent change in polarization state of light in normal incidence on an isotropic nonlinear Kerr medium

    Indian Academy of Sciences (India)

    Hari Prakash; Devendra K Singh

    2010-03-01

    It is shown that all optical polarization states of light except plane and circular polarization states undergo an intensity-dependent change in normal incidence of light in an isotropic nonlinear Kerr medium. This effect should be detectable and we propose an experiment for detecting nonlinear susceptibility involved in that part of nonlinear polarization, which depends on the polarization state of light also.

  12. The influence of low intensities of light pollution on bat communities in a semi-natural context.

    Directory of Open Access Journals (Sweden)

    Aurelie Lacoeuilhe

    Full Text Available Anthropogenic light pollution is an increasingly significant issue worldwide. Over the past century, the use of artificial lighting has increased in association with human activity. Artificial lights are suspected to have substantial effects on the ecology of many species, e.g., by producing discontinuities in the territories of nocturnal animals. We analyzed the potential influence of the intensity and type of artificial light on bat activity in a semi-natural landscape in France. We used a species approach, followed by a trait-based approach, to light sensitivity. We also investigated whether the effect of light could be related to foraging traits. We performed acoustic surveys at sites located along a gradient of light intensities to assess the activity of 15 species of bats. We identified 2 functional response groups of species: one group that was light-tolerant and one group that was light-intolerant. Among the species in the latter group that appear to be disadvantaged by lighting conditions, many are rare and threatened in Europe, whereas the species from the former group are better able to thrive in disturbed habitats such as lighted areas and may actually benefit from artificial lighting. Finally, several methods of controlling light pollution are suggested for the conservation of bat communities. Recommendations for light management and the creation of dim-light corridors are proposed; these strategies may play an important role in protecting against the impact of light pollution on nocturnal animals.

  13. Spectral analysis of red scattered sunlight at sunrise

    CERN Document Server

    Zagury, F; Zagury, Frederic; Fujii, Mitsugu

    2003-01-01

    We analyze and fit visible spectra of a red horizon at sunrise. The shape of the spectra consist of a blue continuum followed by a red bump. The reddest spectra are well fitted by the product of a spectrum of extinguished sunlight (Rayleigh extinction + ozone absorption) and 1/lambda^4. The former is essentially the radiation field in the outer atmosphere, at the scattering volume location; the latter corresponds to Rayleigh scattering by the gas. Moving to higher altitudes, a second component, corresponding to the spectrum of a blue sky, must be added. The spectra we have obtained are similar to spectra of red nebulae, suggesting there may be other explanations than an emission process to the red color of some nebulae.

  14. Parameter study for polymer solar modules based on various cell lengths and light intensities

    Energy Technology Data Exchange (ETDEWEB)

    Slooff, L.H.; Burgers, A.R.; Bende, E.E.; Kroon, J.M. [ECN Solar Energy, P.O. Box 1, 1755 ZG Petten (Netherlands); Veenstra, S.C. [ECN Solar Energy, Solliance, High Tech Campus 5, P63, 5656AE Eindhoven (Netherlands)

    2013-10-15

    Polymer solar cells may be applied in portable electronic devices, where light intensity and spectral distribution of the illuminating source can be very different compared to outdoor applications. As the power output of solar cells depends on temperature, light intensity and spectrum, the design of the module must be optimized for the specific illumination conditions in the different applications. The interconnection area between cells in a module must be as narrow as possible to maximize the active area, also called geometrical fill factor, of the module. Laser scribing has the potential to realize this. The optimal width of the interconnection zone depends both on technological limitations, e.g. laser scribe width and the minimal distance between scribes, and electrical limitations like resistive losses. The latter depends on the generated current in the cell and thus also on illumination intensity. Besides that, also the type of junction, i.e. a single or tandem junction, will influence the optimal geometry. In this paper a calculation model is presented that can be used for electrical modeling of polymer cells and modules in order to optimize the performance for the specific illumination conditions.

  15. Pigment-targeted light wavelength and intensity promotes efficient photoautotrophic growth of Cyanobacteria.

    Science.gov (United States)

    Bland, Erik; Angenent, Largus T

    2016-09-01

    A consensus is lacking whether monochromatic rather than broad-spectrum illumination is more efficient for photosynthetic microbe production platforms. Light wavelength and intensity were tuned to pigment composition for growth of the Cyanobacterium Synechocystis PCC 6803. Phycocyanin (PC)-targeting LEDs (620nm) provided more than 6times the peak efficiency of white LEDs, with peak efficiency growth rates of 0.063h(-1) at 81μEm(-2)s(-1) and 0.039h(-1) at 126μEm(-2)s(-1) for red and white LEDs, respectively. Chlorophyll a (Chl a)-targeting LEDs (680- and 440-nm) performed poorly. Indeed, 10 times greater mass abundance was observed for PC than Chl a. PC levels did not change while Chl a levels decreased when Synechocystis transitioned from white light at 50μEm(-2)s(-1) to 250μEm(-2)s(-1) with 620nm, 680nm, or white LEDs. This work demonstrates that light wavelengths and intensity need to be optimized for each strain.

  16. Dependence of parameters of silicon-type photoelectric converters on temperature and light intensity

    Energy Technology Data Exchange (ETDEWEB)

    Borisov, S.N.; Gorodetskiy, S.M.; Grigoreva, G.M.; Zvyagina, K.N.; Kasymakhunova, A.M.

    The performance of silicon-type photoelectric converters with 1 ohm cm nominal electrical resistivity of the material were measured at +20/sup 0/C, using a variable-intensity solar radiation simulator as a light source and keeping the device temperature constant. The data yielded current-voltage curves for various levels of the photocurrent; the total current is equal to the sum of the photocurrent and diode current, also the dependence of current and voltage as well as efficiency on the density of incident radiation power. The current-voltage curves were found to flatten out with increasing light intensity. The results are used for an evaluation of the equivalent-circuit series resistance and its leakage component. The former is calculated from the ideal current-voltage characteristics with correction for a real device. The latter is calculated on the basis of Ohm's law and current balance in a thin front layer, taking into account the presence of a substrate as well as of metal contact tabs on both front and back sides. The current dependence of the resistance thus established indicates that the series resistance consists almost solely of its leakage component under light loads, but becomes increasingly larger than this component under heavier loads. 5 references, 4 figures.

  17. Fresh and evolutionary-type field-aligned irregularities generated near sunrise terminator due to overshielding electric fields

    Science.gov (United States)

    Tulasi Ram, S.; Ajith, K. K.; Yamamoto, M.; Otsuka, Y.; Yokoyama, T.; Niranjan, K.; Gurubaran, S.

    2015-07-01

    The unusual evolution of fresh and intense field-aligned irregularities (FAI) near sunrise terminator which further sustained for more than 90 min of postsunrise period was observed by Equatorial Atmosphere Radar at Kototabang during a minor geomagnetic storm period. These FAI echoes were initially observed around 250-350 km altitudes, growing upward under eastward polarization electric fields indicating the plasma bubbles that are fully depleted along the flux tube. The background low-latitude F layer dynamics that lead to the development of these dawn time FAI have been investigated from two ionosondes at near magnetic conjugate low-latitude locations. A minor geomagnetic storm was in progress which did not appear to cause any large electric field perturbations at preceding postsunset to midnight period over Indonesian sector. However, the prompt penetration of overshielding electric fields associated with sudden northward turning of interplanetary magnetic field Bz caused spectacular ascent of F layer and development of fresh, intense, and upward evolutionary plasma bubbles near sunrise terminator.

  18. Effects of different green light intensities on the growth performance and endocrine properties of barfin flounder Verasper moseri.

    Science.gov (United States)

    Takahashi, Akiyoshi; Kasagi, Satoshi; Murakami, Naoto; Furufuji, Sumihisa; Kikuchi, Shigeto; Mizusawa, Kanta; Andoh, Tadashi

    2017-04-17

    We previously reported that the somatic growth of barfin flounder, Verasper moseri, was effectively stimulated by the green light compared to the blue and red lights. Herein, we report the effects of different green light intensities on the growth and endocrine system of the fish. Fish were reared in a dark room with light from a light-emitting diode (LED) at a peak wavelength of 518nm under controlled photoperiod (10.5:13.5h, light:dark cycle; 06:00-16:30, light) with three levels of photon flux density (PFD)-2 (low), 7 (medium), or 21 (high) μmol·m(-2)·s(-1) at the water surface. The average water temperature was 10.2°C, and the fish were fed until satiety. The fish reared under high PFD of green light showed the highest specific growth rates, followed by the medium PFD group. Under high PFD, the fish showed the highest amount of melanin-concentrating hormone mRNA in their brains and insulin in plasma, while the lowest amount of growth hormone was observed in their pituitary glands. These results suggest that the green light stimulated the growth of barfin flounders in a light intensity-dependent manner in association with their central and peripheral endocrine systems. However, when the fish were reared in an ordinary room where they received both ambient and green LED lights, the fish under LED and ambient light grew faster than those under ambient light only (control). Moreover, no difference was observed in the specific growth rate of the fish reared under the three different green LED light intensities, suggesting that the growth was equally stimulated by the green light within a certain range of intensities under ambient light. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. High-Intensity Discharge Industrial Lighting Design Strategies for the Minimization of Energy Usage and Life-Cycle Cost

    OpenAIRE

    Flory IV, Isaac L.

    2008-01-01

    Worldwide, the electrical energy consumed by artificial lighting is second only to the amount consumed by electric machinery. Of the energy usage attributed to lighting in North America, approximately fifteen percent is consumed by those lighting products that are classified as High-Intensity Discharge (HID). These lighting products, which are dominated by Metal-Halide and High-Pressure Sodium technologies, range in power levels from 35 to 2000 watts and are used in both indoor and outdoor ...

  20. Effects of light intensity and quality on phycobiliprotein accumulation in the cyanobacterium Nostoc sphaeroides Kützing.

    Science.gov (United States)

    Ma, Rui; Lu, Fan; Bi, Yonghong; Hu, Zhengyu

    2015-08-01

    To assess the effects of light intensity and quality on the growth and phycobiliproteins (PBP) accumulation in Nostoc sphaeroides Kützing (N. sphaeroides). Dry weights, dry matter, protein, chlorophyll and PBP contents were higher under 90 μmol m(-2) s(-1) than under other intensities (both higher and lower). Phycocyanin and allophycocyanin increased with light intensity while phycoerythrin decreased. Fresh weights, protein and PBP contents increased at the highest rates under blue light. Red light resulted in higher values of dry matter, phycocyanin and chlorophyll a. White light at 90 μmol m(-2) s(-1) or blue light 30 μmol m(-2) s(-1) were optimal for the growth and phycobiliprotein accumulation in N. sphaeroides.

  1. Membrane development in purple photosynthetic bacteria in response to alterations in light intensity and oxygen tension.

    Science.gov (United States)

    Niederman, Robert A

    2013-10-01

    Studies on membrane development in purple bacteria during adaptation to alterations in light intensity and oxygen tension are reviewed. Anoxygenic phototrophic such as the purple α-proteobacterium Rhodobacter sphaeroides have served as simple, dynamic, and experimentally accessible model organisms for studies of the photosynthetic apparatus. A major landmark in photosynthesis research, which dramatically illustrates this point, was provided by the determination of the X-ray structure of the reaction center (RC) in Blastochloris viridis (Deisenhofer and Michel, EMBO J 8:2149-2170, 1989), once it was realized that this represented the general structure for the photosystem II RC present in all oxygenic phototrophs. This seminal advance, together with a considerable body of subsequent research on the light-harvesting (LH) and electron transfer components of the photosynthetic apparatus has provided a firm basis for the current understanding of how phototrophs acclimate to alterations in light intensity and quality. Oxygenic phototrophs adapt to these changes by extensive thylakoid membrane remodeling, which results in a dramatic supramolecular reordering to assure that an appropriate flow of quinone redox species occurs within the membrane bilayer for efficient and rapid electron transfer. Despite the high level of photosynthetic unit organization in Rba. sphaeroides as observed by atomic force microscopy (AFM), fluorescence induction/relaxation measurements have demonstrated that the addition of the peripheral LH2 antenna complex in cells adapting to low-intensity illumination results in a slowing of the rate of electron transfer turnover by the RC of up to an order of magnitude. This is ascribed to constraints in quinone redox species diffusion between the RC and cytochrome bc1 complexes arising from the increased packing density as the intracytoplasmic membrane (ICM) bilayer becomes crowded with LH2 rings. In addition to downshifts in light intensity as a paradigm

  2. A simple method for correcting spatially resolved solar intensity oscillation observations for variations in scattered light

    Science.gov (United States)

    Jefferies, S. M.; Duvall, T. L., Jr.

    1991-01-01

    A measurement of the intensity distribution in an image of the solar disk will be corrupted by a spatial redistribution of the light that is caused by the earth's atmosphere and the observing instrument. A simple correction method is introduced here that is applicable for solar p-mode intensity observations obtained over a period of time in which there is a significant change in the scattering component of the point spread function. The method circumvents the problems incurred with an accurate determination of the spatial point spread function and its subsequent deconvolution from the observations. The method only corrects the spherical harmonic coefficients that represent the spatial frequencies present in the image and does not correct the image itself.

  3. The effects of light emitting diode therapy following high intensity exercise.

    Science.gov (United States)

    Denis, Romain; O'Brien, Christopher; Delahunt, Eamonn

    2013-05-01

    To determine the effects of light emitting diode therapy (LEDT) irradiation on blood lactate concentration ([La]) clearance, peak power output and fatigue index (FI) following high intensity fatiguing exercise. Single-blinded randomised cross-over placebo controlled trial. University College Dublin, Institute for Sport and Health, Human performance laboratory. Eighteen healthy male athletes were recruited from field-based sports (including soccer, hockey and rugby union) and participated in the present study. Dependent variables were the peak power output elicited during the Wingate Anaerobic Test (WAnT), FI and [La] before and after each exercise. WAnT performance was measured prior to high intensity fatiguing exercise (Yo-Yo IR2), prior to LEDT or placebo, and following LEDT or placebo. [La] was measured at baseline, immediately after the Yo-Yo IR2, and in the 3rd, 9th, and 15th min following LEDT or placebo condition. No significant group by treatment interactions were observed for any outcome measures (P > 0.05). We conclude that LEDT irradiation applied following high intensity exercise was not effective and has no immediate effect on [La] clearance, peak power and FI, and thus has no significant effect on muscle recovery in athletes at the intensity and irradiation parameters used in the present study. Further research using different parameters is required to determine how LEDT may contribute to post-exercise recovery. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Intense Pulsed Light Sintering of CH3NH3PbI3 Solar Cells.

    Science.gov (United States)

    Lavery, Brandon W; Kumari, Sudesh; Konermann, Hannah; Draper, Gabriel L; Spurgeon, Joshua; Druffel, Thad

    2016-04-06

    Perovskite solar cells utilizing a two-step deposited CH3NH3PbI3 thin film were rapidly sintered using an intense pulsed light source. For the first time, a heat treatment has shown the capability of sintering methylammonium lead iodide perovskite and creating large crystal sizes approaching 1 μm without sacrificing surface coverage. Solar cells with an average efficiency of 11.5% and a champion device of 12.3% are reported. The methylammonium lead iodide perovskite was subjected to 2000 J of energy in a 2 ms pulse of light generated by a xenon lamp, resulting in temperatures significantly exceeding the degradation temperature of 150 °C. The process opens up new opportunities in the manufacturability of perovskite solar cells by eliminating the rate-limiting annealing step, and makes it possible to envision a continuous roll-to-roll process similar to the printing press used in the newspaper industry.

  5. Influence of NaNO3 concentration and incident light intensity on Nannochloropsis oculata lipid accumulation

    OpenAIRE

    Lara Regina Soccol Gris; Anderson de Campos Paim; Marcelo Farenzena; Jorge Otávio Trierweiler

    2013-01-01

    This study aimed at evaluating the best conditions for lipid accumulation in the marine microalga Nannochloropsis oculata in an airlift photobioreactor. Experiments were carried out following a central composite design with the following variables: temperature (19 to 29°C), sodium nitrate concentration (NaNO3) in the culture medium (f/2) (25 to 125 mg.L-1) and incident light intensity (49 to 140 µE.m-2s-1). The maximum lipid production was 132.4 mg.L-1 under the following conditions: 27°C, Na...

  6. Thermo chemical stability of cadmium sulfide nanoparticles under intense pulsed light irradiation and high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Colorado, H.A., E-mail: hcoloradolopera@ucla.edu [Materials Science and Engineering Department, University of California, Los Angeles, CA 90095 (United States); Universidad de Antioquia, Mechanical Engineering, Medellin (Colombia); Dhage, S.R. [International Advanced Research Center for Powder Metallurgy and New Materials (ARCI), Hyderabad 500005 (India); Hahn, H.T. [Materials Science and Engineering Department, University of California, Los Angeles, CA 90095 (United States); Mechanical and Aerospace Engineering Department, University of California, Los Angeles (United States)

    2011-09-15

    Highlights: > In this paper is about the thermochemical stability of CdS nanoparticles under Intense Pulsed Light (IPL) irradiation. > After few irradiation shots over the nano-particles, CdS pillars appeared without phase transformation. > No oxidation was observed during the treatment process. > CdS nanoparticles are thermally stable until around 400 deg. C and 600 deg. C for air and argon atmospheres respectively. > It has been studied and demonstrated the stability of CdS nanoparticles under intense pulsed light and under high temperature conditions. - Abstract: Thermo chemical stability of CdS nanoparticles under an Intense Pulsed Light from a xenon flash lamp and high temperature X-ray Diffraction (XRD) were investigated. The CdS nanoparticles were obtained with a chemical bath method. The CdSO{sub 4} (0.16 M) solution was added to an NH{sub 3} (7.5 M) solution under constant stirring. Afterwards, a thiourea (0.6 M) solution was added. The bath temperature and pH were maintained at 65 deg. C and 10, respectively and the mixture was stirred constantly until a solid precipitate of yellow CdS was produced. Its microstructure was investigated with Scanning Electron Microscopy, and its electronic properties were determined by UV-visible and Photo luminescence Spectroscopy. The microstructure of the sintered CdS nanoparticles, obtained the high temperature XRD, was investigated with EDAX and X-ray micro Tomography. In addition, high temperature XRD and Themogravimetric Analysis tests were conducted over the samples. The CdS nanoparticles' crystallinity increased with the irradiation exposure and they were thermally stable until 600 deg. C in argon atmosphere. However new phases start to appear after annealing at 400 deg. C for 30 min in air atmosphere. The main contribution of this paper was to investigate the stability of CdS nanoparticles under intense light and high temperature conditions. It was found that the number of irradiation shots conducted with the

  7. Low-cost vibration sensor based on dual fiber Bragg gratings and light intensity measurement.

    Science.gov (United States)

    Gao, Xueqing; Wang, Yongjiao; Yuan, Bo; Yuan, Yinquan; Dai, Yawen; Xu, Gang

    2013-09-20

    A vibration monitoring system based on light intensity measurement has been constructed, and the designed accelerometer is based on steel cantilever frame and dual fiber Bragg gratings (FBGs). By using numerical simulations for the dual FBGs, the dependence relationship of the area of main lobes on the difference of initial central wavelengths is obtained and the most optimal choice for the initial value and the vibration amplitude of the difference of central wavelengths of two FBGs is suggested. The vibration monitoring experiments are finished, and the measured data are identical to the simulated results.

  8. Effects of light intensity on the morphology and CAM photosynthesis of Vanilla planifolia Andrews

    Directory of Open Access Journals (Sweden)

    María Claudia Díez

    2017-01-01

    Full Text Available Vanilla planifolia is a neotropical orchid, whose fruits produce the natural vanilla, a fundamental ingredient for the food and cosmetic industry. Because of its importance in the world market, it is cultivated in many tropical countries and recently its cultivation has started in Colombia. This species requires shade for its development; however, the optimal of light conditions are unknown. This work evaluates the effect of different light intensities on CAM photosynthesis, physiology, morphology, and growth of this species. For this, vanilla seedlings were subjected to four treatments of relative illumination (RI (T1=8%, T2=17%, T3=31% and T4=67%. Most CO2 assimilation occurred along night in all treatments, which confirms that vanilla is a strong CAM species. Plants grown under high lighting (67% RI had almost half of the photosynthesis in treatments of intermediate lighting (17 and 31%, which is consistent with the lower nocturnal acid accumulation in that treatment. Likewise, the photochemical efficiency of photosystem II (Fv / Fm showed that in plants of the 67% RI occurred high radiation stress. On the other hand, vanilla plants reached greater length, leaf area, and total biomass when grown under intermediate radiation (17 and 31% RI. These results suggest that high radiation alters the functioning of vanilla plants, inhibiting photosynthesis and growth, and that highly shaded environments not significantly affected the CAM photosynthesis of vanilla; however, in the long-term this species showed higher photosynthesis and growth under intermediate levels of radiation

  9. Phenotypic plasticity of Neonotonia wightii and Pueraria phaseoloidesgrown under different light intensities

    Directory of Open Access Journals (Sweden)

    LEONARDO D.T. SANTOS

    2015-03-01

    Full Text Available Plants have the ability to undergo morphophysiological changes based on availability of light. The present study evaluated biomass accumulation, leaf morphoanatomy and physiology of Neonotonia wightii andPueraria phaseoloides grown in full sunlight, as well as in 30% and 50% shade. Two assays were performed, one for each species, using a randomized block design with 10 replicates. A higher accumulation of fresh mass in the shoot of the plants was observed for both species under cultivation in 50% shade, while no differences were detected between the full sunlight and 30% shade. N. wightii and P. phaseoloides showed increase in area and reduction in thickness leaf when cultivated in 50% shade. There were no changes in photosynthetic rate, stomatal conductance, water use efficiency and evapotranspiration of P. phaseoloidesplants because growth environment. However, the shade treatments caused alterations in physiological parameters of N. wightii. In both species, structural changes in the mesophyll occurred depending on the availability of light; however, the amount of leaf blade tissue remained unaltered. Despite the influence of light intensity variation on the morphophysiological plasticity ofN. wightiiand P. phaseoloides, no effects on biomass accumulation were observed in response to light.

  10. Detection of internal structure by scattered light intensity: Application to kidney cell sorting

    Science.gov (United States)

    Goolsby, C. L.; Kunze, M. E.

    1985-01-01

    Scattered light measurements in flow cytometry were sucessfully used to distinguish cells on the basis of differing morphology and internal structure. Differences in scattered light patterns due to changes in internal structure would be expected to occur at large scattering angles. Practically, the results of these calculations suggest that in experimental situations an array of detectors would be useful. Although in general the detection of the scattered light intensity at several intervals within the 10 to 60 region would be sufficient, there are many examples where increased sensitivity could be acheived at other angles. The ability to measure at many different angular intervals would allow the experimenter to empirically select the optimum intervals for the varying conditions of cell size, N/C ratio, granule size and internal structure from sample to sample. The feasibility of making scattered light measurements at many different intervals in flow cytometry was demonstrated. The implementation of simplified versions of these techniques in conjunction with independant measurements of cell size could potentially improve the usefulness of flow cytometry in the study of the internal structure of cells.

  11. Ultrasound modulated light blood flow measurement using intensity autocorrelation function: a Monte-Carlo simulation

    Science.gov (United States)

    Tsalach, A.; Metzger, Y.; Breskin, I.; Zeitak, R.; Shechter, R.

    2014-03-01

    Development of techniques for continuous measurement of regional blood flow, and in particular cerebral blood flow (CBF), is essential for monitoring critical care patients. Recently, a novel technique, based on ultrasound modulation of light was developed for non-invasive, continuous CBF monitoring (termed ultrasound-tagged light (UTL or UT-NIRS)), and shown to correlate with readings of 133 Xe SPECT1 and laser Doppler2. Coherent light is introduced into the tissue concurrently with an Ultrasound (US) field. Displacement of scattering centers within the sampled volume induced by Brownian motion, blood flow and the US field affects the photons' temporal correlation. Hence, the temporal fluctuations of the obtained speckle pattern provide dynamic information about the blood flow. We developed a comprehensive simulation, combining the effects of Brownian motion, US and flow on the obtained speckle pattern. Photons trajectories within the tissue are generated using a Monte-Carlo based model. Then, the temporal changes in the optical path due to displacement of scattering centers are determined, and the corresponding interference pattern over time is derived. Finally, the light intensity autocorrelation function of a single speckle is calculated, from which the tissue decorrelation time is determined. The simulation's results are compared with in-vitro experiments, using a digital correlator, demonstrating decorrelation time prediction within the 95% confidence interval. This model may assist in the development of optical based methods for blood flow measurements and particularly, in methods using the acousto-optic effect.

  12. Structure and Dynamics of Isolated Internetwork Ca II H Bright Points Observed by Sunrise

    CERN Document Server

    Jafarzadeh, S; Feller, A; Lagg, A; Pietarila, A; Danilovic, S; Riethmüller, T L; Pillet, V Martínez

    2012-01-01

    We aim to improve our picture of the low chromosphere in the quiet-Sun internetwork by investigating the intensity, horizontal velocity, size and lifetime variations of small bright points (BPs; diameter smaller than 0.3 arcsec) observed in the Ca II H 3968 {\\AA} passband along with their magnetic field parameters, derived from photospheric magnetograms. Several high-quality time series of disc-centre, quiet-Sun observations from the Sunrise balloon-borne solar telescope, with spatial resolution of around 100 km on the solar surface, have been analysed to study the dynamics of BPs observed in the Ca II H passband and their dependence on the photospheric vector magnetogram signal. Parameters such as horizontal velocity, diameter, intensity and lifetime histograms of the isolated internetwork and magnetic Ca II H BPs were determined. Mean values were found to be 2.2 km/s, 0.2 arcsec (150 km), 1.48 average Ca II H quiet-Sun and 673 sec, respectively. Interestingly, the brightness and the horizontal velocity of B...

  13. Detection of vortex tubes in solar granulation from observations with Sunrise

    CERN Document Server

    Steiner, O; Gonzalez, N Bello; Nutto, Ch; Rezaei, R; Pillet, V Martinez; Navarro, J A Bonet; Iniesta, J C del Toro; Domingo, V; Solanki, S K; Knolker, M; Schmidt, W; Barthol, P; Gandorfer, A

    2010-01-01

    We have investigated a time series of continuum intensity maps and corresponding Dopplergrams of granulation in a very quiet solar region at the disk center, recorded with the Imaging Magnetograph eXperiment (IMaX) on board the balloon-borne solar observatory Sunrise. We find that granules frequently show substructure in the form of lanes composed of a leading bright rim and a trailing dark edge, which move together from the boundary of a granule into the granule itself. We find strikingly similar events in synthesized intensity maps from an ab initio numerical simulation of solar surface convection. From cross sections through the computational domain of the simulation, we conclude that these `granular lanes' are the visible signature of (horizontally oriented) vortex tubes. The characteristic optical appearance of vortex tubes at the solar surface is explained. We propose that the observed vortex tubes may represent only the large-scale end of a hierarchy of vortex tubes existing near the solar surface.

  14. Effect of light intensity on respiration rate of Spirulina plantensis; Spirulina no kokyu sokudo no oyobosu shodo no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Ohira, Y.; Obata, E.; Kuga, Y.; Ando, K. [Muroran Institute of Technology, Hokkaido (Japan)

    1997-07-10

    Effects of light intensity and irradiation time on respiration rate in the dark period after irradiating are discussed. The specific respiration rate of S. platensis in the dark is a constant value Q1, up to 15-30 minutes, and then rapidly decreases to Q2 after 30 minutes. The specific respiration rate Q1 increases with light intensity. No significant effect of Q1 on irradiation time and Q2 on light intensity is observed. The respiration rate for a long dark time, Q0(=1.2 mg-O2{center_dot}kg-Spirulina{sup -1}centre dots{sup -1}), is almost the same as Q2. The effect of the logarithmic mean light intensity I{sub 1m}[klx] on Q1 is described by the following equation. Q1-Q0 = 13 and I{sub 1m}/(15+I{sub 1m}) 12 refs., 11 figs.

  15. Impact of light intensity on flowering time and plant quality of Antirrhinum majus L. cultivar Chimes White

    Institute of Scientific and Technical Information of China (English)

    MUNIRMuhammad; JAMILMuhammad[; BALOCHJalal-ud-din; KHATTAKKhalidRehman

    2004-01-01

    Shades of different light intensities (29%, 43%, 54%,60% or 68%) along with control (no shade) were studied to observe their effects on the flowering time and plant quality. A hyperbolic relationship was observed between different light intensities under shade,and time to flowering.The total number of flower buds showed a curvilinear relationship with light intensities. Growth parameters related to the plant characteristics such as plant height,leaf area and plant fresh weight were improved under shading treatments at the expense of flowering time and number of flower buds.However,both linear and polynomial models applied assumed that cultivar Chimes White was equally sensitive to light intensity throughout development.

  16. Intensity of blue LED light: a potential stimulus for biomass and lipid content in fresh water microalgae Chlorella vulgaris.

    Science.gov (United States)

    Atta, Madiha; Idris, Ani; Bukhari, Ataullah; Wahidin, Suzana

    2013-11-01

    Light quality and the intensity are key factors which render microalgae as a potential source of biodiesel. In this study the effects of various intensities of blue light and its photoperiods on the growth and lipid content of Chlorella vulgaris were investigated by using LED (Light Emitting Diode) in batch culture. C. vulgaris was grown for 13 days at three different light intensities (100, 200 and 300 μmol m(-2)s(-1)). Effect of three different light and dark regimes (12:12, 16:08 and 24:00 h Light:Dark) were investigated for each light intensity at 25°C culture temperature. Maximum lipid content (23.5%) was obtained due to high efficiency and deep penetration of 200 μmol m(-2)s(-1) of blue light (12:12 L:D) with improved specific growth (1.26 d(-1)) within reduced cultivation time of 8 days. White light could produce 20.9% lipid content in 10 days at 16:08 h L:D.

  17. Insights into the differences in leaf functional traits of heterophyllous Syringa oblata under different light intensities

    Institute of Scientific and Technical Information of China (English)

    Hongguang Xiao; Congyan Wang; Jun Liu; Lei Wang; Daolin Du

    2015-01-01

    Many plants exhibit heterophylly; the spatially and temporally remarkable ontogenetic differences in leaf morphology may play an adaptative role in their success under diverse habitats. Thus, this study aimed to gain insights into differences in leaf functional traits of heterophyllous Syringa oblata Lindl., which has been widely used as an ornamental tree around the world under different light intensities in East China. No significant differences existed in specific leaf area (SLA) between lanceolate-and heart-shaped leaves. Differ-ences in the investment per unit of light capture surface area deployed between lanceolate-and heart-shaped leaves may be not obvious. This may be attributing to the fact that single leaf wet and dry weight of heart-shaped leaves were significantly higher than those of lanceolate leaves but leaf length and leaf thickness of heart-shaped leaves were significantly lower than those of lanceolate leaves. The SLA of shade trees was sig-nificantly higher than that of sun trees. The investment per unit of light capture surface of shade trees was lower than that of sun trees, making it possible to increase light capture and use efficiency in low-light environments. The phenotypic plas-ticity of most leaf functional traits of lanceolate leaves was higher than those of heart-shaped leaves because the former is the juvenile and the latter is the adult leaf shape during the process of phylogenetic development of S. oblate. The higher range of phenotypic plasticity of leaf thickness and leaf moisture for sun trees may be beneficial to obtain a more efficient control of water loss and nutrient deprivation in high-light environments, and the lower range of phenotypic plas-ticity of single leaf wet and dry weight, and SLA for shade trees may gain an advantage to increase resource (especially light) capture and use efficiency in low-light environments. In brief, the successfully ecological strategy of plants is to find an optimal mode for the trade

  18. Productivity of duckweed (Lemna minor as alternative forage feed for livestock in different light intensities

    Directory of Open Access Journals (Sweden)

    Uti Nopriani

    2015-12-01

    Full Text Available Duckweed (Lemna minor is a small aquatic plant that grow and float in water and spread extensively. Lemna minor is potential as a source of high quality forage. This study aimed to determine optimal light intensity on Lemna minor to generate maximum productivity. Parameters observed were physical-biological and chemical characteristics of the media (pH value, temperature, cover area, decreased of media volume, BOD, COD, nitrate, nitrite and phosphate, plant growth acceleration (number of shoots, leaf diameter and chlorophyll-a, biomass production, doubling time of cover area and the number of daughters. This study was done based on a completely randomized design with 4 levels of shading. While treatment was: without shading, shading 30%, shading 50% and shading 70% using paranet shade. Each treatment consisted of 4 replications. Result showed that the productivity of Lemna minor included the number of daughters, chlorophyll-a, biomass production, cover area, absorbed phosphate and doubling time the number of daughters reached the highest level without shading treatment (1007,21-2813,57 lux. The decrease of intensity of light, the increase the diameter of leaf. Decrease of media volume was positively correlated to size of cover area. Biomass production influenced by a wide doubling time of cover area and number of daughters.

  19. Effect of intense pulsed light on immature burn scars: A clinical study

    Directory of Open Access Journals (Sweden)

    Arindam Sarkar

    2014-01-01

    Full Text Available Introduction: As intense pulsed light (IPL is widely used to treat cutaneous vascular malformations and also used as non-ablative skin rejunuvation to remodel the skin collagen. A study has been undertaken to gauze the effect of IPL on immature burn scars with regard to vascularity, pliability and height. Materials and Methods: This study was conducted between June 2013 and May 2014, among patients with immature burn scars that healed conservatively within 2 months. Photographic evidence of appearance of scars and grading and rating was done with Vancouver Scar Scale parameters. Ratings were done for both case and control scar after the completion of four IPL treatment sessions and were compared. Results: Out of the 19 cases, vascularity, pliability and height improved significantly (P < 0.05 in 13, 14 and 11 scars respectively following IPL treatment. Conclusions: Intense pulsed light was well-tolerated by patients, caused good improvement in terms of vascularity, pliability, and height of immature burn scar.

  20. Characterization of material ablation driven by laser generated intense extreme ultraviolet light

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Nozomi, E-mail: tanaka-n@ile.osaka-u.ac.jp; Masuda, Masaya; Deguchi, Ryo; Murakami, Masakatsu; Fujioka, Shinsuke; Yogo, Akifumi; Nishimura, Hiroaki [Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Sunahara, Atsushi [Institute for Laser Technology, 2-6 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2015-09-14

    We present a comparative study on the hydrodynamic behaviour of plasmas generated by material ablation by the irradiation of nanosecond extreme ultraviolet (EUV or XUV) or infrared laser pulses on solid samples. It was clarified that the difference in the photon energy deposition and following material heating mechanism between these two lights result in the difference in the plasma parameters and plasma expansion characteristics. Silicon plate was ablated by either focused intense EUV pulse (λ = 9–25 nm, 10 ns) or laser pulse (λ = 1064 nm, 10 ns), both with an intensity of ∼10{sup 9 }W/cm{sup 2}. Both the angular distributions and energy spectra of the expanding ions revealed that the photoionized plasma generated by the EUV light differs significantly from that produced by the laser. The laser-generated plasma undergoes spherical expansion, whereas the EUV-generated plasma undergoes planar expansion in a comparatively narrow angular range. It is presumed that the EUV radiation is transmitted through the expanding plasma and directly photoionizes the samples in the solid phase, consequently forming a high-density and high-pressure plasma. Due to a steep pressure gradient along the direction of the target normal, the EUV plasma expands straightforward resulting in the narrower angular distribution observed.

  1. Nutritional quality of ten leafy vegetables harvested at two light intensities.

    Science.gov (United States)

    Colonna, Emma; Rouphael, Youssef; Barbieri, Giancarlo; De Pascale, Stefania

    2016-05-15

    The nutritional composition of ten leafy vegetables (chicory, green lettuce, lamb's lettuce, mizuna, red chard, red lettuce, rocket, spinach, Swiss chard, and tatsoi) and quality traits of the selected leafy vegetables in relation to the light intensity (low and high Photosynthetically Active Radiation; PAR) at time of harvest were determined. Irrespective of the light intensity at time of harvest, the highest leaf dry matter (DM), proteins, nitrate, P, K and Ca contents were observed in rocket followed by mizuna. The highest lipophilic antioxidant activity (LAA) was recorded in red lettuce and rocket, whereas ascorbic acid (AA) and total phenolic (TP) contents of red lettuce were higher compared to the other leafy vegetables. When leafy vegetables were harvested at low as opposed to high PAR, the leaf content was higher in DM, protein, K, Ca and Mg, hydrophilic antioxidant activity (HAA), and LAA by 12.5%, 10.0%, 12.6%, 23.7%, 14.1%, 11.9%, and 18.5%, respectively. The highest values in TP for chicory, green lettuce, lamb's lettuce, mizuna, red chard, and red lettuce, were observed under high PAR.

  2. Light intensity regulation of cab gene transcription is signaled by the redox state of the plastoquinone pool

    Energy Technology Data Exchange (ETDEWEB)

    Escoubas, J.M.; Lomas, M.; LaRoche, J. [Brookhaven National Lab., Upton, NY (United States)] [and others

    1995-10-24

    The eukaryotic green alga Dunaliella tertiolecta acclimates to decreased growth irradiance by increasing cellular levels of light-harvesting chlorophyll protein complex apoproteins associated with photosystem II (LHCIIs), whereas increased growth irradiance elicits the opposite response. Nuclear run-on transcription assays and measurements of cab mRNA stability established that light intensity-dependent changes in LHCII are controlled at the level of transcription. cab gene transcription in high-intensity light was partially enhanced by reducing plastoquinone with 3-(3,4-dichlorophenyl)-1,1-dimethyl urea (DCMU), whereas it was repressed in low-intensity light by partially inhibiting the oxidation of plastoquinol with 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB). Uncouplers of photosynthetic electron transport and inhibition of water splitting had no effect on LHCII levels. These results strongly implicate the redox state of the plastoquinone pool in the chloroplast as a photon-sensing system that is coupled to the light-intensity regulation of nuclear-encoded cab gene transcription. The accumulation of cellular chlorophyll at low-intensity light can be blocked by cytoplasmically directed phosphatase inhibitors, such as okadaic acid, microcystin L-R, and tautomycin. Gel mobility-shift assays revealed that cells grown in high-intensity light contained proteins that bind to the promoter region of a cab gene carrying sequences homologous to higher plant light-responsive elements. On the basis of these experimental results, we propose a model for a light intensity signaling system where cab gene expression is reversibly repressed by a phosphorylated factor coupled to the redox status of plastoquinone through a chloroplast protein kinase. 54 refs., 5 figs.

  3. Transition from coherent to incoherent acceleration of nonthermal relativistic electron induced by an intense light pulse

    Science.gov (United States)

    Liu, Y. L.; Kuramitsu, Y.; Moritaka, T.; Chen, S. H.

    2017-03-01

    Nonthermal acceleration of relativistic electrons due to the wakefield induced by an intense light pulse is investigated. The spectra of the cosmic rays are well represented by power-law. Wakefield acceleration has been considered as a candidate for the origins of cosmic rays. The wakefield can be excited by an intense laser pulse as large-amplitude precursor waves in collisionless shocks in the universe. National Central University (NCU) 100-TW laser facility in Taiwan is able to provide high-repetition rate and short intense laser. To experimentally study the wakefield acceleration for the spectrum of the cosmic rays, particle-in-cell simulations are performed to calculate the energy distribution functions of electrons in fixed laser conditions with various plasma densities. The transitions of wakefields from coherent to inherent are observed as the plasma density increases. The distribution functions indicate that the smooth nonthermal power-law spectra with an index of -2 appear when the incoherent wakefields are excited. In contrast, the mono-peak appear in the spectra when the coherent wakefields are excited. The incoherent wakefields yielding the power-law spectra imply the stochastic accelerating of electrons. To explain the universal nonthermal power-law spectra with an index of -2, we described and extended the stochastic acceleration model based on Fokker-Planck equation by assuming the transition rate as an exponential function.

  4. A NUMERICAL MODEL OF THE LASER LIGHT INTENSITY TRANSVERSAL DISTRIBUTION INTO UNDEFORMED/DEFORMED OPTICAL FIBERS

    Directory of Open Access Journals (Sweden)

    Paula COPĂESCU

    2009-12-01

    Full Text Available Preliminary results obtained in developing a numerical model of laser light intensity transversedistribution into undeformed/deformed step index optical fiber are presented. The main purpose ofthe presented preliminary numerical modelling results consists in developing a simple method offiber optical sensors interrogation, especially concerning strain and pressure measurements. It is apotential important matter for aeronautical research and industry because of the more extendeduse of fibre optic sensors in aircraft manufacturing. The developed numerical model relies onsolving the equations of electromagnetic waves propagation into optical fibers by using the finiteelement method technique (FEM. The results of numerical simulation obtained by consideringsingle mode or multimode and various laser wavelengtsh are presented. One importantachievement reported in this paper consists in preliminary experimental results concerning themodification of laser intensity transverse distribution observed for multimode optical fiber with andwithout perpendicular mechanical load. The reported preliminary experimental results confirm tosome extent the predictions of numerical simulations regarding laser intensity distribution underlow and medium transverse mechanical load. One important conclusion of this paper consists inthe future development of fiber optic sensor interrogation techniques based on the reportedpreliminary experimental and numerical simulation results.

  5. Effects of low-intensity polarized visible laser radiation on skin burns: a light microscopy study.

    Science.gov (United States)

    Ribeiro, Martha Simões; Da Silva, Daniela De Fátima Teixeira; De Araújo, Carlos Eugênio Nabuco; De Oliveira, Sérgio Ferreira; Pelegrini, Cleusa Maria Raspantini; Zorn, Telma Maria Tenório; Zezell, Denise Maria

    2004-02-01

    This study was carried out to investigate the influence of low-intensity polarized visible laser radiation on the acceleration of skin wound healing. Low-level laser therapy (LLLT) at adequate wavelength, intensity, and dose can accelerate tissue repair. However, there is still unclear information about light characteristics, such as coherence and polarization. Some studies indicate that linearly polarized light can survive through long propagation distance in biological tissue. Three burns about 6 mm in diameter were created on the back of rats with liquid N(2). Lesion "L(//)" was irradiated by He-Ne laser (lambda = 632.8 nm), D= 1.0 J/cm(2), with linear polarization parallel to the spinal column of the rat. Lesion "L(inverted v)" was irradiated using the same laser and dose, but the light polarization was aligned perpendicularly to the relative orientation. Lesion "C" was not irradiated in order to be considered as control. The animals were sacrificed at day 3-17 after lesion creation. Samples were collected and prepared for histological analysis. Histological analysis showed that the healing of irradiated wounds was faster than that of non-irradiated wounds. Moreover, it was observed that skin wound repair is dependent on polarization orientation with respect to a referential axis as the animal's spinal column. Consequently, "L(//)" was completely healed after 17 days, whereas "L (perpendicular) " showed a moderate degree of healing after the same period. These results indicate that the relative direction of the laser polarization plays an important role in the wound healing process when highly coherent He-Ne laser is used.

  6. Influence of iron precipitated condition and light intensity on microalgae activated sludge based wastewater remediation.

    Science.gov (United States)

    Anbalagan, Anbarasan; Schwede, Sebastian; Lindberg, Carl-Fredrik; Nehrenheim, Emma

    2017-02-01

    The indigenous microalgae-activated sludge (MAAS) process during remediation of municipal wastewater was investigated by studying the influence of iron flocculation step and light intensity. In addition, availability of total phosphorous (P) and photosynthetic activity was examined in fed-batch and batch mode under northern climatic conditions and limited lighting. This was followed by a semi-continuous operation with 4 d of hydraulic retention time and mean cell residence time of 6.75 d in a photo-bioreactor (PBR) with varying P availability. The fed-batch condition showed that P concentrations of 3-4 mg L(-1) were effective for photosynthetic chl. a development in iron flocculated conditions. In the PBR, the oxygen evolution rate increased with increase in the concentration of MAAS (from 258 to 573 mg TSS L(-1)) at higher surface photosynthetic active radiation (250 and 500 μmol m(-2) s(-1)). Additionally, the rate approached a saturation phase at low MAAS (110 mg L(-1)) with higher light intensities. Semi-continuous operation with luxury P uptake and effective P condition showed stable average total nitrogen removal of 88 and 92% respectively, with residual concentrations of 3.77 and 2.21 mg L(-1). The corresponding average P removal was 68 and 59% with residual concentrations of 2.32 and 1.75 mg L(-1). The semi-continuous operation produced a rapidly settleable MAAS under iron flocculated condition with a settling velocity of 92-106 m h(-1) and sludge volume index of 31-43 ml g(-1) in the studied cases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Study on light intensity in the process of photocatalytic degradation of indoor gaseous formaldehyde for saving energy

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Liping [Research Center of Combustion and Environmental Technology, School of Mechanical and Power Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030 (China); Liu, Zhenyan [Research Center of Combustion and Environmental Technology, School of Mechanical and Power Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030 (China)]. E-mail: yanglp@sjtu.edu.cn

    2007-03-15

    The light intensity, one of the most important factors for photocatalysis, directly influences the photocatalytic reaction rate and the utilization ratio of energy. Its rational selection has vital significance for saving energy. In the present paper, light energy losses in the heterogeneous photocatalysis process were analyzed. A method was presented to determine appropriate light intensities for the photocatalytic degradation of indoor gaseous volatile organic compounds (VOCs) based on the degradation mechanism. For simplifying the method, an excess coefficient of light intensity was defined based on the assumption of complete utilization of excited electron-hole pairs. The excess coefficients and the appropriate light intensities for degrading formaldehyde were determined according to the data from a titania-coated glass plate reactor and a titania-coated reticular foam nickel reactor. The results showed that the derived light intensities according to our method were appropriate. Good degradation performance and high utilization ratio of light energy can be attained simultaneously when the excess coefficient was 1.3-1.5 for formaldehyde with the concentration from 20.45 {mu}mol/m{sup 3} (0.5 ppm) to 81.8 {mu}mol/m{sup 3} (2 ppm), which is the concentration range of formaldehyde in 'sick buildings'.

  8. Profiling of Indoor Plant to Deteriorate Carbon Dioxide Using Low Light Intensity

    Directory of Open Access Journals (Sweden)

    Suhaimi Shamsuri Mohd Mahathir

    2016-01-01

    Full Text Available Reasonable grounds that human needs the plants because their abilities reduce carbon dioxide (CO2. However, it is not constantly human with the plants, especially in the building. This paper intends to study the abilities of seven plants (Anthurium, Dumb Cane, Golden Pothos, Prayer Plants, Spider Plant, and Syngonium to absorb CO2 gas. The research was conducted in chambers (one cubic meter with temperature, lux intensity and CO2 concentration at 25±10C, 300 lux, and 450±10 ppm. Before experimental were carried out, all plants selected should be assimilated with an indoor setting for performance purpose, and the experiment was conducted during daytime (9 am-5 pm. The experiments run in triplicate. Based on the results that are using extremely low light that ever conducted on plants, only Spider Plants are not capable to absorb CO2, instead turn up the CO2 rate during respiration. Meanwhile, Prayer Plant is the most plant performed with CO2 reduction is 7.62%, and this plant also has equivalent results in triplicate study based on an ANOVA test with significant value at 0.072. The conclusions of this research, only Spider Plant cannot survive at indoor condition with extremely low light for plants live and reduce CO2 concentration for indoor air quality (IAQ. The rate of 300 lux is a minimum light at indoor that are set by the Department of Occupational Safety and Health (DOSH, Malaysia.

  9. Intense pulsed light treatment of cadmium telluride nanoparticle-based thin films.

    Science.gov (United States)

    Dharmadasa, Ruvini; Lavery, Brandon; Dharmadasa, I M; Druffel, Thad

    2014-04-09

    The search for low-cost growth techniques and processing methods for semiconductor thin films continues to be a growing area of research; particularly in photovoltaics. In this study, electrochemical deposition was used to grow CdTe nanoparticulate based thin films on conducting glass substrates. After material characterization, the films were thermally sintered using a rapid thermal annealing technique called intense pulsed light (IPL). IPL is an ultrafast technique which can reduce thermal processing times down to a few minutes, thereby cutting production times and increasing throughput. The pulses of light create localized heating lasting less than 1 ms, allowing films to be processed under atmospheric conditions, avoiding the need for inert or vacuum environments. For the first time, we report the use of IPL treatment on CdTe thin films. X-ray diffraction (XRD), optical absorption spectroscopy (UV-Vis), scanning electron microscopy (SEM) and room temperature photoluminescence (PL) were used to study the effects of the IPL processing parameters on the CdTe films. The results found that optimum recrystallization and a decrease in defects occurred when pulses of light with an energy density of 21.6 J cm(-2) were applied. SEM images also show a unique feature of IPL treatment: the formation of a continuous melted layer of CdTe, removing holes and voids from a nanoparticle-based thin film.

  10. Angular intensity of nonequilibrium interfacial dynamic light scattering: Succinonitrile and naphthalene

    Science.gov (United States)

    Williams, L. M.; Cummins, H. Z.; Ladeira, L. O.; Mesquita, O. N.

    1992-03-01

    We have investigated the phenomenon of intense dynamic light scattering at the nonequilibrium crystal-melt interface in succinonitrile and naphthalene, in order to resolve the ongoing controversy over its origin. Of the several models that have been proposed to explain this phenomenon, the microbubble model of H. Z. Cummins et al. [Solid State Commun. 60, 857 (1986)] and the mesophase model proposed by J. Bilgram and co-workers [P. Boni, J. H. Bilgram, and W. Kanzig, Phys. Rev. A 28, 2953 (1983)] are the only two still considered to be consistent with most of the experimental observations. In these experiments the angular dependence of the scattered light was investigated. In the mesophase model the angular dependence of the scattered light is described by the Ornstein-Zernike form I(q)=I0(1+q2ξ2)-1, whereas light scattered by bubbles can be modeled by the Mie scattering theory. The data for both materials were found to be incompatible with the Ornstein-Zernike form, but could be reasonably well fit by the Mie theory. The behavior of the onset of scattering was also investigated, and it was found that the product R0t0v2g was a constant, where R0 is the onset radius, t0 the onset time, and vg the crystal growth velocity. This result is consistent with the analysis of Mesquita et al. [Phys. Rev. B 38, 1550 (1988)], in which the onset of the scattering was modeled by considering the rate of buildup of dissolved gas at the advancing crystal-melt interface. The time taken for the disappearance of the scattering after growth was terminated was also investigated. Lastly, the gases dissolved in our samples of succinonitrile were identified by mass spectroscopy and found to have a composition similar to air.

  11. Modeling the interaction of light intensity, nutrient concentration and uranium toxicity in Lemna minor

    Energy Technology Data Exchange (ETDEWEB)

    Zimmer, E.; Horemans, N.; Vandenhove, H. [Belgian Nuclear Research Centre SCK-CEN (Belgium); Cedergreen, N. [University of Copenhagen (Denmark); Jager, T. [Vrije Universiteit Amsterdam (Netherlands)

    2014-07-01

    Radioecology aims at assessing the effect of radionuclides and radiation on the environment. Since we cannot test every possible environmental situation in the laboratory, we need modeling approaches to extrapolate the results of toxicity assays to environmentally relevant scenarios. Therefore, it is of crucial importance to understand the effect of relevant environmental factors, such as nutrients, temperature and light on the toxicity of the test. Radionuclides are often found to induce the production of reactive oxygen species (ROS). In plants, an overload of ROS can lead to disturbances of the photosynthetic system. Since the light intensity determines the efficiency of the photo-systems in plants, it can be expected to interact with the effect of radionuclides. The nutrient concentration of the test medium determines the physiological state of the plant, affecting in turn the plant's capability of dealing with stress and hence influences the toxicity of the contaminant. To study the interaction of stressors with environmental conditions, mechanistic effect modeling is promoted widely in ecotoxicology. In principle, the modelling aims at a mechanistic understanding of the different processes causing the stress individually, and integrating them in one framework to study their joint effect and possible interaction. We here present a mechanistic effect model for Lemna minor (common duckweed), which is based on Dynamic Energy Budget (DEB) theory. Models based on DEB have been used widely to study the effects of compounds on animals. Due to its general applicability to all types of organisms, it holds potential to be used for comparison of species and compounds in a broad context. Energy uptake from the environment is modeled explicitly, and metabolic rates are set to depend on temperature in DEB models. Therefore, they can be used to extrapolate effects to a wide range of environmentally relevant scenarios. Until now, the DEB research in ecotoxicology has

  12. Clinical application of intense pulsed light depilation technology in total auricular reconstruction.

    Science.gov (United States)

    Guo, Ying; Shan, Jing; Zhang, Tianyu

    2017-08-01

    Although ear reconstruction technology has been highly developed in recent years, hair growth on the reconstructed ear has plagued both surgeons and patients. In this paper, the authors introduce a clinical application of intense pulsed light depilation in total auricular reconstruction. From August 2012 to August 2013, 27 patients (28 ears) suffering from congenital microtia were treated by intense pulsed light depilation (650-950-nm filter, initial fluence of 14-16 J/cm(2) and gradually increased, pulse width of 30-50 ms, spot size of 20 × 30 mm(2), intervals of 6-8 weeks, a total of four sessions) either before or after auricular reconstruction. According to the treatment situation at diagnosis, the patients were divided into two groups: the preoperative group and the postoperative group. There were no differences between the two groups in terms of age or initial fluence for hair removal; however, there were less treatments in the former than in the latter group (preoperative group 4.1 ± 0.3, postoperative group 4.7 ± 0.7, F = 9.10, P = 0.006), and the maximum fluence used for hair removal was lower in the former than in the latter group (preoperative group 18-20 J/cm(2), postoperative group 19-22 J/cm(2), F = 22.31, P < 0.001). After follow-up for ≥4-6 months, the effective rate was 100% in the preoperative group, and the effective rate was 80% in the postoperative group. Intense pulsed light depilation technology is a reasonable complementary approach to total auricular reconstruction. And preoperative depilation is recommended over postoperative depilation. The non-invasive modern photonic technology can resolve the problem of postoperative residual hair on the reconstructed auricle, improving auricular shape and increasing patient satisfaction. In addition, an adequately set preoperative hair removal area can provide surface skin that is most similar to normal auricle skin for auricular reconstruction.

  13. New findings regarding light intensity and its effects as a zeitgeber in the Sprague-Dawley rat

    Science.gov (United States)

    Tischler, A. C.; Winget, C. M.; Holley, D. C.; Deroshia, C. W.; Gott, J.; Mele, G.; Callahan, P. X.

    1993-01-01

    In most mammals, the suprachiasmatic nucleus of the anterior hypothalamus has been implicated as the central driving mechanism of circadian rhythmicity. The photic input from the retina, via the retino-hypothalamic tract, and modulation from the pineal gland help regulate the clock. In this study, we investigated the effects of low light intensity on the circadian system of the Sprague-Dawley rat. A series of light intensity experiments were conducted to determine if a light level of 0.1 Lux will maintain entrained circadian rhythms of feeding, drinking, and locomotor activity.

  14. STS-56 Earth observation of a Canadian sunrise taken aboard Discovery, OV-103

    Science.gov (United States)

    1993-01-01

    STS-56 Earth observation taken aboard Discovery, Orbiter Vehicle (OV) 103, is of a Canadian sunrise. Low clouds on the eastern horizon are blocking most of the direct sunlight as the sun climbs over the northern Atlantic in this Canadian sunrise scene. Bright yellow colors are sun rays which penetrate through the cloud-free areas while the reds in the scene are primarily illuminated clouds in the troposphere.

  15. A foraging advantage for dichromatic marmosets (Callithrix geoffroyi) at low light intensity.

    Science.gov (United States)

    Caine, Nancy G; Osorio, Daniel; Mundy, Nicholas I

    2010-02-23

    Most New World monkey species have both dichromatic and trichromatic individuals present in the same population. The selective forces acting to maintain the variation are hotly debated and are relevant to the evolution of the 'routine' trichromatic colour vision found in catarrhine primates. While trichromats have a foraging advantage for red food compared with dichromats, visual tasks which dichromats perform better have received less attention. Here we examine the effects of light intensity on foraging success among marmosets. We find that dichromats outperform trichomats when foraging in shade, but not in sun. The simplest explanation is that dichromats pay more attention to achromatic cues than trichromats. However, dichromats did not show a preference for foraging in shade compared with trichromats. Our results reveal several interesting parallels with a recent study in capuchin monkeys (Cebus capucinus), and suggest that dichromat advantage for certain tasks contributes to maintenance of the colour vision polymorphism.

  16. Light intensity simulation in real space by viewing locations for autostereoscopic display design

    Science.gov (United States)

    Jo, Jungguen; Lee, Kwang-Hoon; Lee, Dong-Su; Park, Min-Chul; Son, Jung-Young; Ju, Byeong-Kwon

    2013-05-01

    Autostereoscopy is a common method for providing 3D perception to viewers without glasses. They produce 3D images with a wide perspective, and can achieve the effect of observing different images visible on the same plane from difference point of view. In autostereoscopic displays, crosstalk occurs when incomplete isolation of the left and right images so that one leakage into the other. This paper addresses a light intensity simulator that can calculate crosstalk according to variable viewing positions by automatically tracking heads of viewers. In doing so, we utilize head tracking technique based on infrared laser sensors to detect the observers' viewing positions. Preliminary results show that the proposed system was appropriate to be operated in designing the autostereoscopic displays ensuring human safety.

  17. Recent Developments in UV Optics for Ultra-Short, Ultra-Intense Coherent Light Sources

    Directory of Open Access Journals (Sweden)

    Daniele Cocco

    2015-01-01

    Full Text Available With the advent of Free Electron Lasers and general UV ultra-short, ultra-intense sources, optics needed to transport such radiation have evolved significantly to standard UV optics. Problems like surface damage, wavefront preservation, beam splitting, beam shaping, beam elongation (temporal stretching pose new challenges for the design of beam transport systems. These problems lead to a new way to specify optics, a new way to use diffraction gratings, a search for new optical coatings, to tighter and tighter polishing requirements for mirrors, and to an increased use of adaptive optics. All these topics will be described in this review article, to show how optics could really be the limiting factor for future development of these new light sources.

  18. Investigation of super-resolution processing algorithm by target light-intensity search in digital holography

    Science.gov (United States)

    Neo, Atsushi; Kakue, Takashi; Shimobaba, Tomoyoshi; Masuda, Nobuyuki; Ito, Tomoyoshi

    2017-04-01

    Digital holography is expected to be useful in the analysis of moving three-dimensional (3D) image measurement. In this technique, a two-dimensional interference fringe recorded using a 3D image is captured with an image sensor, and the 3D image is reproduced on a computer. To obtain the reproduced 3D images with high spatial resolution, a high-performance image sensor is required, which increases the system cost. We propose an algorithm for super-resolution processing in digital holography that does not require a high-performance image sensor. The proposed algorithm wherein 3D images are considered as the aggregation of object points improves spatial resolution by performing a light-intensity search of the reproduced image and the object points.

  19. High-resolution and wide-bandwidth light intensity fiber optic displacement sensor for MEMS metrology.

    Science.gov (United States)

    Orłowska, Karolina; Świątkowski, Michał; Kunicki, Piotr; Kopiec, Daniel; Gotszalk, Teodor

    2016-08-01

    We report on the design, properties, and applications of a high-resolution and wide-bandwidth light intensity fiber optic displacement sensor for microelectromechanical system (MEMS) metrology. There are two types of structures that the system is dedicated to: vibrating with both high and low frequencies. In order to ensure high-frequency and high-resolution measurements, frequency down mixing and selective signal processing were applied. The obtained effective measuring bandwidth ranges from single hertz to 1 megahertz. The achieved resolution presented here is 116  pm/Hz1/2 and 138  pm/Hz1/2 for low-frequency and high-frequency operation modes, respectively, whereas the measurement of static displacement is 100 μm.

  20. Lighting up the Christmas tree: high-intensity laser interactions with a nano-structured target

    CERN Document Server

    Gonoskov, A; Ilderton, A; Mackenroth, F; Marklund, M

    2014-01-01

    We perform a numerical study of the interaction of a high-intensity laser pulse with a nano-structured target. In particular, we study a target where the nano-structuring increases the absorption rate as compared to the flat target case. The transport of electrons within the target, and in particular in the nano-structure, is analysed. It is shown that it is indeed possible, using a terawatt class laser, to light up a nano-scale Christmas tree. Due to the form of the tree we achieve very strong edge fields, in particular at the top where the star is located. Such edge fields, as here located at ion rich spots, makes strong acceleration gradients possible. It also results in a nice, warm glow suitable for the holiday season.

  1. Laser-induced photo emission detection: data acquisition based on light intensity counting

    Science.gov (United States)

    Yulianto, N.; Yudasari, N.; Putri, K. Y.

    2017-04-01

    Laser Induced Breakdown Detection (LIBD) is one of the quantification techniques for colloids. There are two ways of detection in LIBD: optical detection and acoustic detection. LIBD is based on the detection of plasma emission due to the interaction between particle and laser beam. In this research, the changing of light intensity during plasma formations was detected by a photodiode sensor. A photo emission data acquisition system was built to collect and transform them into digital counts. The real-time system used data acquisition device National Instrument DAQ 6009 and LABVIEW software. The system has been tested on distilled water and tap water samples. The result showed 99.8% accuracy by using counting technique in comparison to the acoustic detection with sample rate of 10 Hz, thus the acquisition system can be applied as an alternative method to the existing LIBD acquisition system.

  2. High Precision Stokes Polarimetry for Scattering Light using Wide Dynamic Range Intensity Detector

    Directory of Open Access Journals (Sweden)

    Shibata Shuhei

    2015-01-01

    Full Text Available This paper proposes a Stokes polarimetry for scattering light from a sample surface. To achieve a high accuracy measurement two approaches of an intensity detector and analysis algorism of a Stokes parameter were proposed. The dynamic range of this detector can achieve up to 1010 by combination of change of neutral-density (ND filters having different density and photon counting units. Stokes parameters can be measured by dual rotating of a retarder and an analyzer. The algorism of dual rotating polarimeter can be calibrated small linear diattenuation and linear retardance error of the retarder. This system can measured Stokes parameters from −20° to 70° of its scattering angle. It is possible to measure Stokes parameters of scattering of dust and scratch of optical device with high precision. This paper shows accuracy of this system, checking the polarization change of scattering angle and influence of beam size.

  3. Electromagnetic Coupling Between High Intensity LHC Beams and the Synchrotron Radiation Monitor Light Extraction System

    CERN Document Server

    Andreazza, W; Bravin, E; Caspers, F; Garlasch`e, M; Gras, J; Goldblatt, A; Lefevre, T; Jones, R; Metral, E; Nosych, A; Roncarolo_, F; Salvant, B; Trad, G; Veness, R; Vollinger, C; Wendt, M

    2013-01-01

    The CERN LHC is equipped with two Synchrotron Radiation Monitor (BSRT) systems used to characterise transverse and longitudinal beam distributions. Since the end of the 2011 LHC run the light extraction system, based on a retractable mirror, has suffered deformation and mechanical failure that is correlated to the increase in beam intensity. Temperature probes have associated these observations to a strong heating of the mirror support with a dependence on the longitudinal bunch length and shape, indicating the origin as electromagnetic coupling between the beam and the structure. This paper combines all this information with the aim of characterising and improving the system in view of its upgrade during the current LHC shutdown. Beam-based observations are presented along with electromagnetic and thermomechanical simulations and complemented by laboratory measurements, including the study of the RF properties of different mirror bulk and coating materials.

  4. Different roles of cyclic electron flow around photosystem I under sub-saturating and saturating light intensities in tobacco leaves

    Directory of Open Access Journals (Sweden)

    Wei eHuang

    2015-10-01

    Full Text Available In higher plants, the generation of proton gradient across the thylakoid membrane (pH through cyclic electron flow (CEF has mainly two functions: 1 to generate ATP and balance the ATP/NADPH energy budget, and 2 to protect photosystems I and II against photoinhibition. The intensity of light under which plants are grown alters both CEF activity and the ATP/NADPH demand for primary metabolic processes. However, it is unclear how the role of CEF is affected by the level of irradiance that is applied during the growth and measurement periods. We studied the role of CEF at different light intensities in leaves from sun- and shade-grown plants. At 849 μmol photons m-2 s-1, both types of leaves had nearly the same degree of CEF activation. Modeling of the ATP/NADPH demand revealed that, at this light intensity, the contribution of CEF toward supplying ATP was much higher in the sun leaves. Meanwhile, the shade leaves showed higher levels of non-photochemical quenching and the P700 oxidation ratio. Therefore, at 849 μmol photons m-2 s-1, CEF mainly helped in the synthesis of ATP in the sun leaves, but functioned in photoprotection for the shade leaves. When the light intensity increased to 1976 μmol photons m-2 s-1, CEF activation was greatly enhanced in the sun leaves, but its contribution to supplying ATP changed slightly. These results indicate that the main role of CEF is altered flexibly in response to light intensity. In particular, CEF mainly contributes to balancing the ATP/NADPH energy budget under sub-saturating light intensities. When exposed to saturating light intensities, CEF mainly protects photosynthetic apparatus against photoinhibition.

  5. Contributions of DPOR at Low Light Intensity to Chlorophyll Biosynthesis and Growth in the Synechocystis sp.PCC 6803

    Institute of Scientific and Technical Information of China (English)

    黄卫; 吴庆余; 余久久

    2004-01-01

    The chlL gene encoding one component of light-independent (dark) protochlorophyllide oxido reductase (DPOR) was deleted in cyanobacterium Synechocystis sp. PCC 6803 (S.6803). The resulting chlL mutant lost DPOR activity. No significant differences of chlorophyll (Chi) content and growth rate were observed between the wild and the mutant strains grown at 50 μE · m-2· s-1 light intensity for photomixtrophic and photoautotrophic growth. However, differences were observed at 1 μE · m-2 · s-1 light intensity. For photomixtrophic growth, the mutant Chi content was 50% of the wild content with continuous light and 35.7% of the wild content with a 10 h light/14 h dark cycle. For photoautotriphic growth, the mutant Chi level was 76.3% of the wild content with continuous light and 63.2% with a 10 h light/14 h dark cycle. The results indicate that DPOR contributes to Chi synthesis and increases the growth rate in cyanobacteria phototrophically cultured at 1μE · m-2 ·s-1 light intensity. In contrast, the photosynthetic capacity on a per-cell basis of the mutant is 5% higher than that of the wild strain with continuous light and 27% higher than that of the wild strain with a 10 h light/14 h dark cycle at 1 μE · m-2 · s-1 light intensity for photoautotrophic growth. With the low Chi content, the cyanobacteria have the ability to improve their photosynthetic capacity by decreasing the ratio of PSI to PSII by unknown morphological or physiological means.

  6. [Species-dependence of the pattern of plant photosynthetic rate response to light intensity transition from saturating to limiting one].

    Science.gov (United States)

    Chen, Yue; Xu, Da-Quan

    2007-12-01

    By observing the photosynthetic responses of leaves to changes in light intensity and CO(2) concentration it was found that among the more than 50 plant species examined 32 species and 25 species showed respectively the V pattern and L pattern of the photosynthetic response to light intensity transition from saturating to limiting one (Figs.1 and 2 and Table 1). The pattern of photosynthetic response to light intensity transition is species-dependent but not leaf developmental stage-dependent (Fig.3). The species-dependence was not related to classification in taxonomy because the photosynthetic response might display the two different patterns (V and L) in plants of the same family, for example, rice and wheat (Gramineae), soybean and peanut (Leguminosae). It seemed to be related to the pathway of photosynthetic carbon assimilation because all of the C(4) plants examined (maize, green bristlegrass and thorny amaranth) displayed the L pattern. It might be related to light environment where the plants originated. The V pattern of photosynthetic response to light intensity transition was often observed in some plants grown in shade habitats, for example, sweet viburnum and Japan fatsia, while the L pattern was frequently observed in those plants grown in sunny habitats, for example, ginkgo and cotton. Furthermore, the ratio of electron transport rate to carboxylation rate in vivo measured at limiting light was far higher in the V pattern plants (mostly higher than 10) than in the L pattern plants (mostly lower than 5), but the ratio measured at saturating light had no significant difference between the two kinds of plants (Table 2). These results can be explained in part by that the V pattern plant species have larger light-harvesting complex (LHCII) and at saturating light the reversible dissociation of some LHCIIs from PSII reaction center complex occurs. The pattern of photosynthetic response to light intensity transition and the ratio of electron transport rate

  7. High-frequency Oscillations in Small Magnetic Elements Observed with Sunrise/SuFI

    Science.gov (United States)

    Jafarzadeh, S.; Solanki, S. K.; Stangalini, M.; Steiner, O.; Cameron, R. H.; Danilovic, S.

    2017-04-01

    We characterize waves in small magnetic elements and investigate their propagation in the lower solar atmosphere from observations at high spatial and temporal resolution. We use the wavelet transform to analyze oscillations of both horizontal displacement and intensity in magnetic bright points found in the 300 nm and the Ca ii H 396.8 nm passbands of the filter imager on board the Sunrise balloon-borne solar observatory. Phase differences between the oscillations at the two atmospheric layers corresponding to the two passbands reveal upward propagating waves at high frequencies (up to 30 mHz). Weak signatures of standing as well as downward propagating waves are also obtained. Both compressible and incompressible (kink) waves are found in the small-scale magnetic features. The two types of waves have different, though overlapping, period distributions. Two independent estimates give a height difference of approximately 450 ± 100 km between the two atmospheric layers sampled by the employed spectral bands. This value, together with the determined short travel times of the transverse and longitudinal waves provide us with phase speeds of 29 ± 2 km s‑1 and 31 ± 2 km s‑1, respectively. We speculate that these phase speeds may not reflect the true propagation speeds of the waves. Thus, effects such as the refraction of fast longitudinal waves may contribute to an overestimate of the phase speed.

  8. The influence of photoperiod and light intensity on the growth and photosynthesis of Dunaliella salina (chlorophyta) CCAP 19/30.

    Science.gov (United States)

    Xu, Yanan; Ibrahim, Iskander M; Harvey, Patricia J

    2016-09-01

    The green microalga Dunaliella salina survives in a wide range of salinities via mechanisms involving glycerol synthesis and degradation and is exploited for large amounts of nutraceutical carotenoids produced under stressed conditions. In this study, D. salina CCAP 19/30 was cultured in varying photoperiods and light intensities to study the relationship of light with different growth measurement parameters, with cellular contents of glycerol, starch and carotenoids, and with photosynthesis and respiration. Results show CCAP 19/30 regulated cell volume when growing under light/dark cycles: cell volume increased in the light and decreased in the dark, and these changes corresponded to changes in cellular glycerol content. The decrease in cell volume in the dark was independent of cell division and biological clock and was regulated by the photoperiod of the light/dark cycle. When the light intensity was increased to above 1000 μmol photons m(-2) s(-1), cells displayed evidence of photodamage. However, these cells also maintained the maximum level of photosynthesis efficiency and respiration possible, and the growth rate increased as light intensity increased. Significantly, the intracellular glycerol content also increased, >2-fold compared to the content in light intensity of 500 μmol photons m(-2) s(-1), but there was no commensurate increase in the pool size of carotenoids. These data suggest that in CCAP 19/30 glycerol stabilized the photosynthetic apparatus for maximum performance in high light intensities, a role normally attributed to carotenoids.

  9. Front versus rear side light-ion acceleration from high-intensity laser-solid interactions

    Science.gov (United States)

    Willingale, L.; Petrov, G. M.; Maksimchuk, A.; Davis, J.; Freeman, R. R.; Matsuoka, T.; Murphy, C. D.; Ovchinnikov, V. M.; Van Woerkom, L.; Krushelnick, K.

    2011-01-01

    The source of ions accelerated from high-intensity laser interactions with thin foil targets is investigated by coating a deuterated plastic layer either on the front, rear or both surfaces of thin foil targets. The originating surface of the deuterons is therefore known and this method is used to assess the relative source contributions and maximum energies using a Thomson parabola spectrometer to obtain high-resolution light-ion spectra. Under these experimental conditions, laser intensity of (0.5-2.5) × 1019 W cm-2, pulse duration of 400 fs and target thickness of 6-13 µm, deuterons originating from the front surface can gain comparable maximum energies as those from the rear surface and spectra from either side can deviate from Maxwellian. Two-dimensional particle-in-cell simulations model the acceleration and show that any presence of a proton rich contamination layer over the surface is detrimental to the deuteron acceleration from the rear surface, whereas it is likely to be less influential on the front side acceleration mechanism.

  10. Emotion differentiation and intensity during acute tobacco abstinence: A comparison of heavy and light smokers.

    Science.gov (United States)

    Sheets, Erin S; Bujarski, Spencer; Leventhal, Adam M; Ray, Lara A

    2015-08-01

    The ability to recognize and label discrete emotions, termed emotion differentiation, is particularly pertinent to overall emotion regulation abilities. Patterns of deficient emotion differentiation have been associated with mood and anxiety disorders but have yet to be examined in relation to nicotine dependence. This study employed ecological momentary assessment to examine smokers' subjective experience of discrete emotions during 24-h of forced tobacco abstinence. Thirty daily smokers rated their emotions up to 23 times over the 24-hour period, and smoking abstinence was biologically verified. From these data, we computed individual difference measures of emotion differentiation, overall emotion intensity, and emotional variability. As hypothesized, heavy smokers reported poorer negative emotion differentiation than light smokers (d=0.55), along with more intense negative emotion (d=0.97) and greater negative emotion variability (d=0.97). No differences were observed in positive emotion differentiation. Across the sample, poorer negative emotion differentiation was associated with greater endorsement of psychological motives to smoke, including negative and positive reinforcement motives, while positive emotion differentiation was not.

  11. Intense pulsed light: A promising therapy in treatment of acne vulgaris

    Directory of Open Access Journals (Sweden)

    Manjunatha Puttaiah

    2017-01-01

    Full Text Available Background: Medical treatment of acne vulgaris includes a variety of topical and oral medications. Poor compliance, lack of durable remission, potential side effects are common drawbacks to these treatment. Therefore, there is a growing demand for a fast, safe and side effect free novel therapy. Light-based therapies are an attractive alternative acne therapy because they potentially offer more rapid onset and better patient compliance with a low incidence of adverse events. Aim: To study the efficacy of intense pulsed light in treatment of acne vulgaris. Materials and Methods: Twenty five patients with acne vulgaris were subjected to IPL. Baseline grading of acne was done. IPL was administered every 2weeks for 4 sessions. Grading was done after the end of treatment. Clinical photographs were taken for evaluation. Results: All patients showed a reduction in the number of acne lesions after 4 sessions of IPL. No significant side effects were noted. Patients also noted an improvement in skin texture. Conclusion: IPL showed beneficial effects in the treatment of acne.

  12. Treatment of Persistent Facial Postinflammatory Hyperpigmentation With Novel Pulse-in-Pulse Mode Intense Pulsed Light.

    Science.gov (United States)

    Park, Ji-Hye; Kim, Jung-In; Kim, Won-Serk

    2016-02-01

    Postinflammatory hyperpigmentation (PIH) is an acquired hypermelanosis induced by various causes including inflammatory dermatoses, injury, or cosmetic procedures, such as lasers or chemical peels, and it tends to affect dark-skinned people with greater frequency and severity. There are a variety of treatment options for PIH, including topical agents, chemical peels, laser, and light therapy. However, the results are not up to expectation. The purpose of this study was to examine the clinical efficacy and safety of novel pulse-in-pulse mode intense pulsed light (IPL) for the treatment of persistent facial PIH in Korean patients. Twenty-five Korean female patients (Fitzpatrick skin types III-V) with persistent facial PIH were enrolled in the study. The patients were treated with novel pulse-in-pulse mode IPL for 4 sessions at 1-week interval and 4 sessions at 2-week intervals. Treatment efficacy and patient satisfaction were evaluated using photographs and questionnaires. After 2 months of all treatments, 23 patients (92%) had more than 50% improvement and 22 patients (88%) were satisfied with the treatments. No adverse effects or aggravations were reported. The pulse-in-pulse mode IPL treatment is effective and safe for persistent facial PIH in dark-skinned patients.

  13. Photodissociation dynamics of weakly bound He H2 + in intense light fields

    Science.gov (United States)

    Szidarovszky, Tamás; Yamanouchi, Kaoru

    2016-12-01

    Photoinduced dynamics of a weakly bound triatomic molecule He H2 + exposed to electromagnetic radiation is investigated by time-dependent quantum wave-packet propagation. Adopting a two-dimensional linear H-H-He model, the three lowest-lying potential energy surfaces (PESs) and corresponding dipole moment surfaces are constructed. One of the two characteristic excited PESs of He H2 + leads to the charge-transfer reaction H2 ++He → H2+H e+ and the other corresponds to the first excited state of H2 + perturbed by the presence of He. When He H2 + is exposed to a femtosecond intense ultraviolet light pulse (I =4 ×1014W c m-2 , λ =400 nm ), both of the two excited PESs are found to be coupled with the light field and a variety of reaction pathways become opened so that HeH, He H+ , H2, H2 +,H , H+ , He, and H e+ are produced. Simulations also show that the anharmonic coupling between the two stretching vibrational modes in He H2 + leads to the stabilization of the H2 + moiety against the decomposition into H + H+ compared with bare H2 +. The theoretical findings of the formation of He H+ composed of the most abundant elements in the universe are also discussed in view of the theoretical modeling of the chemical reactions proceeding in the primordial gas and in the interstellar medium.

  14. Periodic Variations in the Coronal Green Line Intensity and their Connection with the White-light Coronal Structures

    Indian Academy of Sciences (India)

    Milan Minarovjech; Milan Rybansky; Vojtech Rusin

    2000-09-01

    We present an analysis of short time-scale intensity variations in the coronal green line as obtained with high time resolution observations. The observed data can be divided into two groups. The first one shows periodic intensity variations with a period of 5 min. the second one does not show any significant intensity variations. We studied the relation between regions of coronal intensity oscillations and the shape of whitelight coronal structures. We found that the coronal green-line oscillations occur mainly in regions where open white-light coronal structures are located.

  15. Photosynthetic recovery and acclimation to excess light intensity in the rehydrated lichen soil crusts

    Science.gov (United States)

    Wu, Li; Lei, Yaping; Lan, Shubin; Hu, Chunxiang

    2017-01-01

    As an important successional stage and main type of biological soil crusts (BSCs) in Shapotou region of China (southeastern edge of Tengger Desert), lichen soil crusts (LSCs) often suffer from many stresses, such as desiccation and excess light intensity. In this study, the chlorophyll fluorescence and CO2 exchange in the rehydrated LSCs were detected under a series of photosynthetically active radiation (PAR) gradients to study the photosynthetic acclimation of LSCs. The results showed that although desiccation leaded to the loss of photosynthetic activity in LSCs, the fluorescence parameters including Fo, Fv and Fv/Fm of LSCs could be well recovered after rehydration. After the recovery of photosynthetic activity, the effective photosynthetic efficiency ΦPSII detected by Imaging PAM had declined to nearly 0 within both the lichen thallus upper and lower layers when the PAR increased to 200 μE m-2 s-1, however the net photosynthesis detected by the CO2 gas analyzer in the LSCs still appeared when the PAR increased to 1000 μE m-2 s-1. Our results indicate that LSCs acclimating to high PAR, on the one hand is ascribed to the special structure in crust lichens, making the incident light into the lichen thallus be weakened; on the other hand the massive accumulation of photosynthetic pigments in LSCs also provides a protective barrier for the photosynthetic organisms against radiation damage. Furthermore, the excessive light energy absorbed by crust lichens is also possibly dissipated by the increasing non-photochemical quenching, therefore to some extent providing some protection for LSCs. PMID:28257469

  16. Eutrophication and algal blooms in channel type reservoirs: A novel enclosure experiment by changing light intensity

    Institute of Scientific and Technical Information of China (English)

    Chengjin Cao; Binghui Zheng; Zhenlou Chen; Minsheng Huang; Jialei Zhang

    2011-01-01

    To explore eutrophication and algal bloom mechanisms in channel type reservoirs,a novel enclosure experiment was conducted by changing light intensity (LI) in the Daning River of the Three Gorges Reservoir (TGR).Square enclosures (side 5.0 m) were covered on the surface with shading materials of different thickness,and with their bases open to the river.Changes and characteristics of the main eutrophication factors under the same water quality and hydrodynamic conditions but different LI were evaluated.All experimental water samples were neutral and alkalescent,with high nitrogen and phosphate concentrations,low potassium permanganate index,stable water quality,and different LI.At the same water depth,LI decreased with increasing shade material,while dissolved oxygen and water temperature were both stable.The growth peak of phytoplankton was with light of 345-4390 lux underwater or 558-7450lux above the water surface,and water temperature of 25.6-26.5℃.Algae were observed in all water samples,accounting for 6 phylum and 57 species,with algal density changing frequently.The results showed that significantly strong or weak light was unfavorable for phytoplankton growth and the function together with suitable temperature and LI and ample sunshine encouraged algal blooms under the same water quality and hydrodynamic conditions.Correlation analysis indicated that algae reduced gradually lengthwise along water depth in the same enclosure while pH became high.The power exponent relationship between chlorophyll a (Chl-a) and LI was found by curve fitting,that is Chi-a =K(LI)n.

  17. Influence of Light Intensity on Growth and Pigment Production by Monascus ruber in Submerged Fermentation.

    Science.gov (United States)

    Bühler, Rose Marie Meinicke; Müller, Bruna Luíse; Moritz, Denise Esteves; Vendruscolo, Francielo; de Oliveira, Debora; Ninow, Jorge Luiz

    2015-07-01

    To reduce environmental problems caused by glycerine accumulation and to make the production of biodiesel more profitable, crude glycerin without treatment was used as substrate for obtaining higher value-added bioproducts. Monascus ruber is a filamentous fungus that produces pigments, particularly red ones, which are used for coloring foods (rice wine and meat products). The interest in developing pigments from natural sources is increasing due to the restriction of using synthetic dyes. The effects of temperature, pH, microorganism morphology, aeration, nitrogen source, and substrates have been studied in the cultivation of M. ruber. In this work, it was observed that light intensity is also an important factor that should be considered for understanding the metabolism of the fungus. In M. ruber cultivation, inhibition of growth and pigment production was observed in Petri dishes and blaffed flasks exposed to direct illumination. Growth and pigment production were higher in Petri dishes and flasks exposed to red light and in the absence of light. Radial growth rate of M. ruber in plates in darkness was 1.50 mm day(-1) and in plates exposed to direct illumination was 0.59 mm day(-1). Maximum production of red pigments (8.32 UA) and biomass (8.82 g L(-1)) were obtained in baffled flasks covered with red film and 7.17 UA of red pigments, and 7.40 g L(-1) of biomass was obtained in flasks incubated in darkness. Under conditions of 1248 lux of luminance, the maximum pigment production was 4.48 UA, with production of 6.94 g L(-1) of biomass, indicating that the fungus has photoreceptors which influence the physiological responses.

  18. Influence of light intensity on surface free energy and dentin bond strength of core build-up resins.

    Science.gov (United States)

    Shimizu, Y; Tsujimoto, A; Furuichi, T; Suzuki, T; Tsubota, K; Miyazaki, M; Platt, J A

    2015-01-01

    We examined the influence of light intensity on surface free energy characteristics and dentin bond strength of dual-cure direct core build-up resin systems. Two commercially available dual-cure direct core build-up resin systems, Clearfil DC Core Automix with Clearfil Bond SE One and UniFil Core EM with Self-Etching Bond, were studied. Bovine mandibular incisors were mounted in acrylic resin and the facial dentin surfaces were wet ground on 600-grit silicon carbide paper. Adhesives were applied to dentin surfaces and cured with light intensities of 0 (no irradiation), 200, 400, and 600 mW/cm(2). The surface free energy of the adhesives (five samples per group) was determined by measuring the contact angles of three test liquids placed on the cured adhesives. To determine the strength of the dentin bond, the core build-up resin pastes were condensed into the mold on the adhesive-treated dentin surfaces according to the methods described for the surface free energy measurement. The resin pastes were cured with the same light intensities as those used for the adhesives. Ten specimens per group were stored in water maintained at 37°C for 24 hours, after which they were shear tested at a crosshead speed of 1.0 mm/minute in a universal testing machine. Two-way analysis of variance (ANOVA) and a Tukey-Kramer test were performed, with the significance level set at 0.05. The surface free energies of the adhesive-treated dentin surfaces decreased with an increase in the light intensity of the curing unit. Two-way ANOVA revealed that the type of core build-up system and the light intensity significantly influence the bond strength, although there was no significant interaction between the two factors. The highest bond strengths were achieved when the resin pastes were cured with the strongest light intensity for all the core build-up systems. When polymerized with a light intensity of 200 mW/cm(2) or less, significantly lower bond strengths were observed. CONClUSIONS: The

  19. EFFECT OF LIGHT INTENSITY ON THE TOTAL LIPID AND FATTY ACID COMPOSITION OF SIX STRAINS OF MARINE DIATOMS

    Institute of Scientific and Technical Information of China (English)

    梁英; 麦康森; 孙世春; 于道展

    2001-01-01

    The effect of light intensity ( 1500 Ix and 5000 Ix) on the total lipid and fatty acid composition of six strains of marine diatoms Cylindrotheca fusiformis (B211 ), Phaeodactylum tricornutum (Bl14, Bl18 and B221) Nitzschia closterium (B222) and Chaetoceros gracilis (B13) was investigated.The total lipids of B13, Bl14, and B211 grown at 5000 Ix were lower than those grown at 1500 Ix. No evident changes were observed in Bl18, B221 and B222. Fatty acid composition changed considerably at different light intensity although no consistent correlation between the relative proportion of a single FA and light intensity. The major fatty acids of the 6 strains were 14:0, 16:0, 16:l(n- 7) and 20:5(n-3) . Cylindrothecafusiformis had high percentage of 20:4n - 6 (9.2 - 10.9% ) . The total polyunsaturated fatty acid /rl all 6 strains decreased with increasing light intensity. The percentage of the highly unsaturated fatty acid eicosapentaenoic acid (EPA) decreased with increasing light intensity in all strains except Chaetoceros gracilis.

  20. Cystic acne improved by photodynamic therapy with short-contact 5-aminolevulinic acid and sequential combination of intense pulsed light and blue light activation.

    Science.gov (United States)

    Melnick, Stuart

    2005-01-01

    Photodynamic therapy with short-contact 5-aminolevulinic acid (Levulan Kerastick, Dusa Pharmaceuticals, Inc.) and activation by intense pulsed light in an initial treatment and blue light in 3 subsequent treatments has resulted in significant improvement in severity of acne, reduction in the number of lesions, improvement in skin texture, and smoothing of scar edges in an Asian patient with severe (class 4) facial cystic acne and scarring.

  1. Interactive effects of photoperiod and light intensity on blood physiological and biochemical reactions of broilers grown to heavy weights.

    Science.gov (United States)

    Olanrewaju, H A; Purswell, J L; Collier, S D; Branton, S L

    2013-04-01

    The effects of photoperiod, light intensity, and their interaction on blood acid-base balance, metabolites, and electrolytes in broiler chickens under environmentally controlled conditions were examined in 2 trials. A 3 × 3 factorial experiment in a randomized complete block design was used in this study. In each trial, all treatment groups were provided 23L:1D with 20 lx of intensity from placement to 7 d, and then subjected to the treatments. The 9 treatments consisted of 3 photoperiods [long/continuous (23L:1D) from d 8 to 56, regular/intermittent (2L:2D), and short/nonintermittent (8L:16D) from d 8 to 48 and 23L:1D from d 49 to 56, respectively] and exposure to 3 light intensities (10, 5.0, and 0.5 lx) from d 8 through d 56 at 50% RH. Feed and water were provided ad libitum. Venous blood samples were collected on d 7, 14, 28, 42, and 56. Main effects indicated that short/nonintermittent photoperiod significantly (P light intensity, or their interaction. There was no effect of light intensity on most of the blood variables examined. Acid-base regulation during photoperiod and light intensity exposure did not deteriorate despite a lower pH and higher partial pressure of CO2 with normal HCO3(-). These results indicate that continuous exposure of broiler chickens to varying light intensities had a minor effect on blood physiological variables, whereas the short photoperiod markedly affected most blood physiological variables without inducing physiological stress in broilers.

  2. Purifying Synthetic High-Strength Wastewater by Microalgae Chlorella Vulgaris Under Various Light Emitting Diode Wavelengths and Intensities

    Directory of Open Access Journals (Sweden)

    Zhigang Ge

    2013-06-01

    Full Text Available The high-strength wastewater is now well known as a threat to the natural water since it is highly possible to arouse water eutrophication or algal blooms. The effects of various light emitting diode wavelengths and intensities on the microalgae biological wastewater treatment system was studied in this research. The various nutrient removals and economic efficiencies represented similar variation trends, and these variations under both high C and N loading treatments were similar too. The order for microalgae C. vulgaris reproduction in terms of dry weight and nutrient removal efficiency both were red > white > yellow > blue, under high carbon and nitrogen loading treatments, indicating that the red light was the optimum light wavelength. Furthermore, considering the optimal light intensity in terms of nutrient removal efficiency was 2500 and 2000 μmol/m2•s, while in terms of economic efficiency was 1000, 1500 and 2000 μmol/m2•s. Therefore, the optimum light intensity was found to be 2000 μmol/m2•s. In addition, the optimal experimental illumination time was determined as 120 h. The Chlorella vulgaris microalgae biological wastewater treatment system utilized in this research was able to purify the high-strength carbon and nitrogen wastewater effectively under optimum light wavelength and intensity.

  3. New technologies in lighting systems for high-speed film and photography regarding high-intensity and heat problems

    Science.gov (United States)

    Severon, Burkhard

    1991-04-01

    Increasing frame rates and the heat sensibility of test objects forced the development of new lighting systems. For example at the automotive industry, where continuous light sources are indispensable for the high speed photography of car crash tests and automobile components tests, the further development of high efficient safety systems, so as Air-Bag systems, needs very datailed analysis of the accelerated motions. Frame rates from 2.000 up to 10.000 frames per second are requested and beside adequate camera systems and film material, this also means high intensive lighting systems. The need for high intensity could be easy achieved by the use of additional light fixtures but the request for more intensity comes along with the problem of heat. The test objects and the auxiliary materials become more and more temperature- sensitive. Very offen they have to be used under strict climate conditions. Mainly there where the test objects are already placed inside the illuminated area, the heat radiation of the light sources to the test objects have to be reduced. So high intensive, flicker free and less heat are today's requirements of light performance. This paper will present solutions to meet those demands.

  4. Effect of light intensity on food detection in captive great fruit-eating bats, Artibeus lituratus (Chiroptera: Phyllostomidae).

    Science.gov (United States)

    Gutierrez, Eduardo de A; Pessoa, Valdir F; Aguiar, Ludmilla M S; Pessoa, Daniel M A

    2014-11-01

    Bats are known for their well-developed echolocation. However, several experiments focused on the bat visual system have shown evidence of the importance of visual cues under specific luminosity for different aspects of bat biology, including foraging behavior. This study examined the foraging abilities of five female great fruit-eating bats, Artibeus lituratus, under different light intensities. Animals were given a series of tasks to test for discrimination between a food target against an inedible background, under light levels similar to the twilight illumination (18lx), the full moon (2lx) and complete darkness (0lx). We found that the bats required a longer time frame to detect targets under a light intensity similar to twilight, possibly due to inhibitory effects present under a more intense light level. Additionally, bats were more efficient at detecting and capturing targets under light conditions similar to the luminosity of a full moon, suggesting that visual cues were important for target discrimination. These results demonstrate that light intensity affects foraging behavior and enables the use of visual cues for food detection in frugivorous bats. This article is part of a Special Issue entitled: Neotropical Behaviour.

  5. A clinical survey of the output intensity of 200 light curing units in dental offices across Maharashtra

    Directory of Open Access Journals (Sweden)

    Hegde Vivek

    2009-01-01

    Full Text Available Aim: The purpose of this study is to examine the intensity of light curing units and factors affecting it in dental offices. Materials and Methods: The output intensity of 200 light curing units in dental offices across Maharashtra were examined. The collection of related information (thenumber of months of use of curing unit, the approximate number of times used in a day, and presence or absence of composite build-ups and measurement of the intensity was performed by two operators. L.E.D Radiometer (Kerr was used for measuring the output intensity. The average output intensity was divided into three categories (< 200 mW/cm 2 , 200-400 mW/ cm 2 and> 400 mW/cm 2 . Results: Among the 200 curing units examined, 81 were LED units and 119 were QTH units. Only 10% LED machines and 2% QTH curing units had good intensities (>400 mW/cm 2 . Conclusion: Most of the examined curing lights had low output intensity ranging from 200 to 400 mW/cm 2 , and most of the curing units had composite build-ups on them.

  6. [Effects of forest gap size and light intensity on herbaceous plants in Pinus koraiensis-dominated broadleaved mixed forest].

    Science.gov (United States)

    Duan, Wen-Biao; Wang, Li-Xia; Chen, Li-Xin; Du, Shan; Wei, Quan-Shuai; Zhao, Jian-Hui

    2013-03-01

    1 m x 1 m fixed quadrats were parallelly arranged with a space of 2 m in each of six forest gaps in Pinus koraiensis-dominated broadleaved mixed forest, taking the gap center as the starting point and along east-west and south-north directions. In each quadrat, the coverage and abundance of herbaceous plants at different height levels were investigated by estimation method in June and September 2011, and the matrix characteristics within the quadrats were recorded. Canopy analyzer was used to take fish-eye photos in the selected overcast days in each month from June to September, 2011, and the relative light intensity was calculated by using Gap Light Analyzer 2.0 software. The differences in the relative light intensity and herbaceous plants coverage and richness between different gaps as well as the correlations between the coverage of each species and the direct light, diffuse light, and matrix were analyzed. The results showed that in opening areas and under canopy, the relative light intensity in large gaps was higher than that in small gaps, and the variation ranges of diffuse light and direct light from gap center to gap edge were bigger in large gaps than in small gaps. The direct light reaching at the ground both in large gaps and in small gaps was higher in the north than in the south direction. In the Z1, Z2, Z3, and Z4 zones, both the coverage and the richness of herbaceous plants were larger in large gaps than in small gaps, and the differences of species richness between large and small gaps reached significant level. The coverage of the majority of the herbaceous plants had significant correlations with diffuse light and matrix, and only the coverage of a few herbaceous plants was correlated with direct light.

  7. Effect of light intensity on the degree of ammonia toxicity on PSII activity of Arthrospira platensis and Chlorella vulgaris.

    Science.gov (United States)

    Markou, Giorgos; Muylaert, Koenraad

    2016-09-01

    Herein the effect of increasing light intensity on the degree of ammonia toxicity and its impact on the photosynthetic performance of Arthrospira and Chlorella was investigated using Chl fluorescence as a technique to characterize their photosystem II (PSII) activity. The results revealed that the increase of light intensity amplifies the ammonia toxicity on PSII. Chl fluorescence transients shown that at a given free ammonia (FA) concentration (100mg-N/L), the photochemistry potential decreased by increasing light intensity. The inhibition of the PSII was not reversible either by re-incubating the cells under dark or under decreased FA concentration. Moreover, the decrease of photochemical and non-photochemical quenching (NPQ) of fluorescence suggest that ammonia toxicity decreases the open available PSII centers, as well the inability of PSII to transfer the generated electrons beyond QA. The collapse of NPQ suggests that ammonia toxicity inhibits the photoprotection mechanism(s) and hence renders PSII more sensitive to photoinhibition.

  8. The Effect of Shaking, CO2 Concentration and Light Intensity on Biomass Growth of Green Microalgae Desmodesmus communis

    Directory of Open Access Journals (Sweden)

    J. Vanags

    2015-01-01

    Full Text Available There are many factors that can affect microalgae growth. In this research, four different groups of experiments were set up in order to determine the influence of different mixing conditions, CO2 concentration and light intensities on Desmodesmus communis growth. The range of CO2 concentration in the air - CO2 mixture was 0–16 v/v%, light intensities ranged between 100 µmol m-2s-1 and 300 µmol m-2s-1. The best biomass productivity and biomass yield of 0.54 g d-1 and 3.53 g l-1 respectively were achieved when mixing was provided by using shaker as well as gas bubbling with air - CO2 mixture of 96:4 v/v% and light intensity of 300 µmol m-2s-1. DOI: http://dx.doi.org/10.5755/j01.erem.70.4.8437

  9. [Effects of light intensity on associated enzyme activity and gene expression during callus formation of Vitis vinifera].

    Science.gov (United States)

    Liu, Rong; Yang, Guowei; Wu, Yueyan; Rao, Huiyun; Li, Xuefu; Li, Meiqin; Qian, Pingxian

    2015-08-01

    We analyzed the best light intensity for callus induction and maintenance in Vitis vinifera and explored the mechanism of grape callus browning. Tender stem segments of grape cultivar "gold finger" were used to study the effects of different light intensities (0, 500, 1 000, 1 500, 2 000, 2 500, 3 000 and 4 000 Lx) on the induction rate, browning rate and associated enzyme activity and gene expression during Vitis vinifera callus formation. The callus induction rate under 0, 500, 1 000 and 1 500 Lx was more than 92%, significantly higher than in other treatments (P Vitis vinifera was 1 000-1 500 Lx, higher or lower light intensities significantly impaired normal callus growth.

  10. Sunrise-driven movements of dust on the Moon: Apollo 12 Ground-truth measurements

    Science.gov (United States)

    O'Brien, Brian J.; Hollick, Monique

    2015-12-01

    The first sunrise after Apollo 12 astronauts left the Moon caused dust storms across the site where rocket exhausts had disrupted about 2000 kg of smooth fine dust. The next few sunrises started progressively weaker dust storms, and the Eastern horizon brightened, adding to direct sunlight for half an hour. These Ground truth measurements were made 100 cm above the surface by the 270 g Apollo 12 Dust Detector Experiment we invented in 1966. Dust deposited on the horizontal solar cell during two lunar days after the first sunrise was almost 30% of the total it then measured over 6 years. The vertical east-facing solar cell measured horizon brightening on 14 of the first 17 lunations, with none detected on the following 61 Lunar Days. Based on over 2 million such measurements we propose a new qualitative model of sunrise-driven transport of individual dust particles freed by Apollo 12 activities from strong particle-to-particle cohesive forces. Each sunrise caused sudden surface charging which, during the first few hours, freshly mobilised and lofted the dust remaining free, microscopically smoothing the disrupted local areas. Evidence of reliability of measurements includes consistency among all 6 sensors in measurements throughout an eclipse. We caution Google Lunar XPrize competitors and others planning missions to the Moon and large airless asteroids that, after a spacecraft lands, dust hazards may occur after each of the first few sunrises. Mechanical problems in its first such period stranded Chinese lunar rover Yutu in 2014, although we would not claim yet that the causes were dust. On the other hand, sunrise-driven microscopic smoothing of disturbed areas may offer regular natural mitigations of dust consequences of mining lunar resources and reduce fears that many expeditions might cause excessive fine dust globally around the Moon.

  11. Effects of strain and light intensity on growth performance and carcass characteristics of broilers grown to heavy weights.

    Science.gov (United States)

    Olanrewaju, H A; Miller, W W; Maslin, W R; Collier, S D; Purswell, J L; Branton, S L

    2014-08-01

    Effects of genetic strain and light intensity on growth performance and carcass characteristics of broilers grown to heavy weights were investigated. The experimental design was a randomized complete block design. Treatment structure was a 2 × 5 factorial arrangement with the main factors being strain (Ross × Ross 308, Ross × Ross 708) and light intensity (25, 10, 5, 2.5, and 0.2 lx) with trial as replicates. In each of the 5 trials, chicks of 2 different strains of the same commercial hatchery were equally and randomly distributed into 10 environmentally controlled rooms (5 rooms/strain) at 1 d of age at 50% RH. Each room was randomly assigned 1 of 5 light intensities from 22 to 56 d of age. Feed and water were provided ad libitum. Birds and feed were weighed on 0, 14, 28, 42, and 56 d of age for growth performance. Humoral immune response was determined on d 28, whereas ocular and blood samples were performed on d 42 and 55, respectively. On d 56, 20 (10 males and 10 females) birds/strain from each room were processed to determine weights and yields. Genetic strain was significant (P ≤ 0.05) for most of the examined variables, where Ross × Ross 308 had better growth performance and meat yield in comparison with Ross × Ross 708. Although, there was no main effect of light intensity on growth performance and meat yield, results indicated that birds under 10 and 5 lx intensities showed slightly better growth performance and meat yield compared with birds under 25, 2.5, and 0.2 lx in both strains. There was no effect of strain and light intensity on ocular indices, immune response, plasma corticosterone levels, and mortality. This study shows the positive influence on profits to commercial poultry facilities that are using a low lighting environment to reduce energy cost, optimize feed conversion, and maximize production without compromising the welfare of the broilers.

  12. Light intensity stabilization based on the second harmonic of the photoelastic modulator detection in the atomic magnetometer.

    Science.gov (United States)

    Duan, Lihong; Fang, Jiancheng; Li, Rujie; Jiang, Liwei; Ding, Ming; Wang, Wei

    2015-12-14

    The fluctuations of the probe light intensity seriously affect the performance of the sensitive atomic magnetometer. Here we propose a novel method for the intensity stabilization based on the second harmonic component of the photoelastic modulator (PEM) detection in the atomic magnetometer. The method not only could be used to eliminate the intensity fluctuations of the laser source, but also remove the fluctuations from the optical components caused by the environment. A relative fluctuation of the light intensity of 0.035% was achieved and the corresponding fluctuation of the output signal of the atomic magnetometer has decreased about two orders of magnitude from 4.06% to 0.041%. As the scheme proposed here only contains optical devices and does not require additional feedback controlled equipments, it is especially suitable for the integration of the atomic magnetometer.

  13. Global effects on Ionospheric Weather over the Indian subcontinent at Sunrise and Sunset

    Science.gov (United States)

    Basak, Tamal; Chakrabarti, S. K.; Pal, S.

    2010-10-01

    Study of Very Low Frequency (VLF) electromagnetic wave is very important for knowing the behavior of the Ionospheric layers due to Sunrise-Sunset, Earthquakes, Solar flares, Solar eclipses and other terrestrial and extra terrestrial radiations. We study the properties of the variation of the VLF signal strength theoretically all over Indian sub-continent. As an example, we concentrate on the VLF signal transmitted by Indian Naval Transmitter VTX at Vijayanarayanam (Latitude 08°23', Longitude 77°45') near the southern tip of Indian subcontinent. As has been noticed, several receiving stations placed during the VLF campaign in all over India, the VLF signal strength varies significantly with place and time. To understand the diurnal and seasonal variation of the received signal, a complete knowledge of physics of intensity distribution of the VLF signal is essential. The spatial variation of VLF signal plays an important role in selecting future VLF stations. In the wave-hop theoretical model presented here, horizontally stratified ionospheric layers have been considered. The VLF wave emitted by the transmitter has both the ground wave and the sky wave components. The ground wave attenuates during propagation. The sky wave component experiences reflections by the ionosphere on its way to the receiver and its attenuation depends on the degree of ionization. Intensity variation occurs at a given receiver location for interference among singly and multiply reflected waves. This has been simulated considering some simplified and justifiable assumptions. This spatial variation wave-hop theoretical model developed here has been compared with LWPC code generated results.

  14. Intense light pulses decontamination of minimally processed vegetables and their shelf-life.

    Science.gov (United States)

    Gómez-López, V M; Devlieghere, F; Bonduelle, V; Debevere, J

    2005-08-15

    Intense light pulses (ILP) is a new method intended for decontamination of food surfaces by killing microorganisms using short time high frequency pulses of an intense broad spectrum, rich in UV-C light. This work studied in a first step the effect of food components on the killing efficiency of ILP. In a second step, the decontamination of eight minimally processed (MP) vegetables by ILP was evaluated, and thirdly, the effect of this treatment on the shelf-life of MP cabbage and lettuce stored at 7 degrees C in equilibrium modified atmosphere packages was assessed by monitoring headspace gas concentrations, microbial populations and sensory attributes. Proteins and oil decreased the decontamination effect of ILP, whilst carbohydrates and water showed variable results depending on the microorganism. For this reason, high protein and fat containing food products have little potential to be efficiently treated by ILP. Vegetables, on the other hand, do not contain high concentrations of both compounds and could therefore be suitable for ILP treatment. For the eight tested MP vegetables, log reductions up to 2.04 were achieved on aerobic mesophilic counts. For the shelf-life studies, respiration rates at 3% O2 and 7 degrees C were 14.63, 17.89, 9.17 and 16.83 ml O2/h kg produce for control and treated cabbage, and control and treated lettuce respectively; used packaging configurations prevented anoxic conditions during the storage times. Log reductions of 0.54 and 0.46 for aerobic psychrothrophic count (APC) were achieved after flashing MP cabbage and lettuce respectively. APC of treated cabbage became equal than that from control at day 2, and higher at day 7, when the tolerance limit (8 log) was reached and the panel detected the presence of unacceptable levels of off-odours. Control never reached 8 log in APC and were sensory acceptable until the end of the experiment (9 days). In MP lettuce, APC of controls reached rejectable levels at day 2, whilst that of treated

  15. Optical diffraction tomography microscopy with transport of intensity equation using a light-emitting diode array

    Science.gov (United States)

    Li, Jiaji; Chen, Qian; Zhang, Jialin; Zhang, Zhao; Zhang, Yan; Zuo, Chao

    2017-08-01

    Optical diffraction tomography (ODT) is an effective label-free technique for quantitatively refractive index imaging, which enables long-term monitoring of the internal three-dimensional (3D) structures and molecular composition of biological cells with minimal perturbation. However, existing optical tomographic methods generally rely on interferometric configuration for phase measurement and sophisticated mechanical systems for sample rotation or beam scanning. Thereby, the measurement is suspect to phase error coming from the coherent speckle, environmental vibrations, and mechanical error during data acquisition process. To overcome these limitations, we present a new ODT technique based on non-interferometric phase retrieval and programmable illumination emitting from a light-emitting diode (LED) array. The experimental system is built based on a traditional bright field microscope, with the light source replaced by a programmable LED array, which provides angle-variable quasi-monochromatic illumination with an angular coverage of ±37 degrees in both x and y directions (corresponding to an illumination numerical aperture of ∼0.6). Transport of intensity equation (TIE) is utilized to recover the phase at different illumination angles, and the refractive index distribution is reconstructed based on the ODT framework under first Rytov approximation. The missing-cone problem in ODT is addressed by using the iterative non-negative constraint algorithm, and the misalignment of the LED array is further numerically corrected to improve the accuracy of refractive index quantification. Experiments on polystyrene beads and thick biological specimens show that the proposed approach allows accurate refractive index reconstruction while greatly reduced the system complexity and environmental sensitivity compared to conventional interferometric ODT approaches.

  16. Performance of photoperiod and light intensity on biogas upgrade and biogas effluent nutrient reduction by the microalgae Chlorella sp.

    Science.gov (United States)

    Yan, Cheng; Zheng, Zheng

    2013-07-01

    Biogas is an environment-friendly fuel but that must be upgraded before being utilized. The method about removing CO2 from biogas by microalgal culturing using biogas effluent as nutrient medium in this study could effectively upgrade biogas and simultaneously reduce the biogas effluent nutrient. Results showed that the optimum parameters for microalgal growth and biogas effluent nutrient reduction was moderate light intensity with middle photoperiod. While low light intensity with long photoperiod and moderate light intensity with middle photoperiod obtained the best biogas CO2 removal and biogas upgrade effects. Therefore, the optimal parameters were moderate light intensity 350 μmol m(-2)s(-1) with middle photoperiod 14 h light:10h dark. Under this condition, the microalgal dry weight, CH4 concentration, reduction efficiency of chemical oxygen demand, total nitrogen, and total phosphorus was 615.84 ± 33.07 mg L(-1), 92.16 ± 2.83% (v/v), 88.74 ± 3.45%, 83.94 ± 3.51%, and 80.43 ± 4.17%, respectively.

  17. THE CYTOTOXIC EFFECTS OF LOW INTENSITY VISIBLE AND INFRARED LIGHT ON HUMAN BREAST CANCER (MCF7 CELLS

    Directory of Open Access Journals (Sweden)

    P Peidaee

    2013-03-01

    Full Text Available A concept of using low intensity light therapy (LILT as an alternative approach to cancer treatment is at early stages of development; while the therapeutic effects of LILT as a non-invasive treatment modality for localized joint and soft tissue wound healing are widely corroborated. The LEDs-based exposure system was designed and constructed to irradiate the selected cancer and normal cells and evaluate the biological effects induced by light exposures in visible and infrared light range. In this study, human breast cancer (MCF7 cells and human epidermal melanocytes (HEM cells (control were exposed to selected far infrared light (3400nm, 3600nm, 3800nm, 3900nm, 4100nm and 4300nm and visible and near infrared wavelengths (466nm, 585nm, 626nm, 810nm, 850nm and 950nm. The optical intensities of LEDs used for exposures were in the range of 15µW to 30µW. Cellular morphological changes of exposed and sham-exposed cells were evaluated using light microscopy. The cytotoxic effects of these low intensity light exposures on human cancer and normal cell lines were quantitatively determined by Lactate dehydrogenase (LDH cytotoxic activity and PrestoBlueTM cell viability assays. Findings reveal that far-infrared exposures were able to reduce cell viability of MCF7 cells as measured by increased LDH release activity and PrestoBlueTM assays. Further investigation of the effects of light irradiation on different types of cancer cells, study of possible signaling pathways affected by electromagnetic radiation (EMR and in vivo experimentation are required in order to draw a firm conclusion about the efficacy of low intensity light as an alternative non-invasive cancer treatment.

  18. The Cytotoxic Effects of Low Intensity Visible and Infrared Light on Human Breast Cancer (MCF7 cells

    Directory of Open Access Journals (Sweden)

    P Peidaee

    2013-03-01

    Full Text Available A concept of using low intensity light therapy (LILT as an alternative approach to cancer treatment is at early stages of development; while the therapeutic effects of LILT as a non-invasive treatment modality for localized joint and soft tissue wound healing are widely corroborated. The LEDs-based exposure system was designed and constructed to irradiate the selected cancer and normal cells and evaluate the biological effects induced by light exposures in visible and infrared light range. In this study, human breast cancer (MCF7 cells and human epidermal melanocytes (HEM cells (control were exposed to selected far infrared light (3400nm, 3600nm, 3800nm, 3900nm, 4100nm and 4300nm and visible and near infrared wavelengths (466nm, 585nm, 626nm, 810nm, 850nm and 950nm. The optical intensities of LEDs used for exposures were in the range of 15µW to 30µW. Cellular morphological changes of exposed and sham-exposed cells were evaluated using light microscopy. The cytotoxic effects of these low intensity light exposures on human cancer and normal cell lines were quantitatively determined by Lactate dehydrogenase (LDH cytotoxic activity and PrestoBlueTM cell viability assays. Findings reveal that far-infrared exposures were able to reduce cell viability of MCF7 cells as measured by increased LDH release activity and PrestoBlueTM assays. Further investigation of the effects of light irradiation on different types of cancer cells, study of possible signaling pathways affected by electromagnetic radiation (EMR and in vivo experimentation are required in order to draw a firm conclusion about the efficacy of low intensity light as an alternative non-invasive cancer treatment.

  19. Measuring the fusion cross-section of light nuclei with low-intensity beams

    Energy Technology Data Exchange (ETDEWEB)

    Steinbach, T.K.; Rudolph, M.J.; Gosser, Z.Q.; Brown, K.; Floyd, B.; Hudan, S. [Department of Chemistry and Center for Exploration of Energy and Matter, Indiana University, 2401 Milo B. Sampson Lane, Bloomington, IN 47408 (United States); Souza, R.T. de, E-mail: desouza@indiana.edu [Department of Chemistry and Center for Exploration of Energy and Matter, Indiana University, 2401 Milo B. Sampson Lane, Bloomington, IN 47408 (United States); Liang, J.F.; Shapira, D. [Oak Ridge National Laboratory, Physics Division, Oak Ridge, TN 37831 (United States); Famiano, M. [Department of Physics, Western Michigan University, Kalamazoo, MI 49008 (United States)

    2014-04-11

    We demonstrate an approach to measure the total fusion cross-section for beams of low-intensity light nuclei. Fusion residues resulting from the fusion of {sup 20,16}O+{sup 12}C are directly measured and distinguished from unreacted beam particles on the basis of their energy and time-of-flight. The time-of-flight is measured between a microchannel plate (MCP) detector, which serves as a start, and a segmented silicon detector, which provides a stop. The two main difficulties associated with the initial implementation of this approach are charge trapping in the silicon detector and slit scattering in the MCP detector. Both these obstacles have been characterized and overcome. To reduce atomic slit scattering in the measurement we have eliminated wires from the beam path by developing a gridless MCP detector. The total fusion cross-section for {sup 16}O+{sup 12}C in the energy range E{sub CM}=8.0–12.0 MeV has been measured in agreement with established literature values (down to the 100 mb level)

  20. Reconstructing the fractal dimension of granular aggregates from light intensity spectra.

    Science.gov (United States)

    Tang, Fiona H M; Maggi, Federico

    2015-12-21

    There has been growing interest in using the fractal dimension to study the hierarchical structures of soft materials after realising that fractality is an important property of natural and engineered materials. This work presents a method to quantify the internal architecture and the space-filling capacity of granular fractal aggregates by reconstructing the three-dimensional capacity dimension from their two-dimensional optical projections. Use is made of the light intensity of the two-dimensional aggregate images to describe the aggregate surface asperities (quantified by the perimeter-based fractal dimension) and the internal architecture (quantified by the capacity dimension) within a mathematical framework. This method was tested on control aggregates of diffusion-limited (DLA), cluster-cluster (CCA) and self-correlated (SCA) types, stereolithographically-fabricated aggregates, and experimentally-acquired natural sedimentary aggregates. Statistics of the reconstructed capacity dimension featured correlation coefficients R ≥ 98%, residuals NRMSE ≤ 10% and percent errors PE ≤ 4% as compared to controls, and improved earlier approaches by up to 50%.

  1. Radioprotective Action of Low-Intensity Light into the Red Absorption Band of Endogenous Molecular Oxygen

    Science.gov (United States)

    Ivanov, A. V.; Mashalov, A. A.; Zakharov, S. D.

    2016-08-01

    Application of ionizing radiation in oncology (radiation therapy) is a widespread way to eliminate malignant tumors. Normal tissues are inevitable included in any radiation field, and their reliable protection is actual till now. All attempts to solve the problem are based on search of effective radioprotectors, i.e. chemical compounds of various classes, which should be entered into the patient. To date about 50,000 compounds with some radioprotection properties had been tested, but the most effective of them have been simultaneously the most toxic. Here the preliminary results of researches devoted to development of an optical technique on basis of the light-oxygen effect for the protection of women with breast cancer from side effects of the radiation therapy are presented. A low intensity emission of the semiconductor laser in a red spectral interval was used to excite a very small quantity of endogenous molecular oxygen in O2(1Δg) state. It is shown, that application of the method at occurrence of earliest signs of radiation injury allows notably reducing dangerous breaks in radiation therapy course.

  2. The Retrospective Evaluation of the Efficacy and Safety of IPL (Intense Pulse Light in Hair Removal

    Directory of Open Access Journals (Sweden)

    İlgen Ertam

    2012-06-01

    Full Text Available Background and Design: There are numerous therapeutic methods for hair removal with various success rates. The aim of this study was to evaluate the efficacy of Intense Pulse Light (IPL method for hair removal.Materials and Methods: Ninety patients, who applied for their unwanted hair, were included in the study. IPL was applied to the face, neck, axillary areas, bikini line, sternal area, periareolar areas, and upper and lower extremities. An IPL device (L900 A&M, France was used for hair removal. The results were evaluated according to the clinical improvement (0-25%, 25-50%, 50-75%, 75% and more and patients? satisfaction (very satisfied, satisfied, less satisfied, not satisfied. All results were analyzed using Chi-square test and statistical analysis was performed by SPSS 15.0 for Windows. Results: There were eighty-eight female (97.8% and two male (2.2% patients. The mean age of the patients was 33.62±11.11 (15- 55 years. 13.3% of patients had polycystic ovary syndrome. The mean number of treatments was 6.5 (min-max= 2-11. 53.2% of patients had 50-75% clinical response and 53.2% of patients were satisfied. There were no side effects except mild erythema. Conclusion: We observed that IPL for hair removal was safe and moderately effective in our patients.

  3. Polishing of anaerobic secondary effluent by Chlorella vulgaris under low light intensity

    KAUST Repository

    Cheng, Tuoyuan

    2017-05-29

    To investigate anaerobic secondary effluent polishing by microalgae (Chlorella vulgaris) under low light intensity (14 μmol/m2/s), bubbling column reactors were operated in batches of 8 d with initial ammonium nitrogen 10-50 mg/L, initial phosphate phosphorus 2-10 mg/L and microalgal seed 40 mg/L. Maximum microalgal biomass and minimum generation time were 370.9 mg/L and 2.5 d, respectively. Nitrogen removal (maximum 99.6%) was mainly attributed to microalgal growth rate, while phosphorus removal (maximum 49.8%) was related to microalgal growth rate, cell phosphorus content (maximum 1.5%) and initial nutrients ratio. Dissolved microalgal organics release in terms of chemical oxygen demand (maximum 63.2 mg/L) and hexane extractable material (i.e., oil and grease, maximum 8.5 mg/L) was firstly reported and mainly affected by nitrogen deficiency and deteriorated effluent quality. Ultrafiltration critical flux (16.6-39.5 L/m2/h) showed negative linear correlation to microalgal biomass. Anaerobic membrane bioreactor effluent polishing showed similar results with slight inhibition to synthetic effluent.

  4. Cultivation of Scenedesmus obliquus in photobioreactors: effects of light intensities and light-dark cycles on growth, productivity, and biochemical composition.

    Science.gov (United States)

    Gris, Barbara; Morosinotto, Tomas; Giacometti, Giorgio M; Bertucco, Alberto; Sforza, Eleonora

    2014-03-01

    One of the main parameters influencing microalgae production is light, which provides energy to support metabolism but, if present in excess, can lead to oxidative stress and growth inhibition. In this work, the influence of illumination on Scenedesmus obliquus growth was assessed by cultivating cells at different light intensities in a flat plate photobioreactor. S. obliquus showed a maximum growth rate at 150 μmol photons m(-2) s(-1). Below this value, light was limiting for growth, while with more intense illumination photosaturation effects were observed, although cells still showed the ability to duplicate. Looking at the biochemical composition, light affected the pigment contents only while carbohydrate, lipid, and protein contents remained stable. By considering that in industrial photobioreactors microalgae cells are subjected to light-dark cycles due to mixing, algae were also grown under pulsed illumination (5, 10, and 15 Hz). Interestingly, the ability to exploit pulsed light with good efficiency required a pre-acclimation to the same conditions, suggesting the presence of a biological response to these conditions.

  5. The intensity threshold of colour vision in a passerine bird, the blue tit (Cyanistes caeruleus).

    Science.gov (United States)

    Gomez, Doris; Grégoire, Arnaud; Del Rey Granado, Maria; Bassoul, Marine; Degueldre, David; Perret, Philippe; Doutrelant, Claire

    2014-11-01

    Many vertebrates use colour vision for vital behaviour but their visual performance in dim light is largely unknown. The light intensity threshold of colour vision is known only for humans, horses and two parrot species. Here, we first explore this threshold in a passerine bird, the blue tit (Cyanistes caeruleus). Using classic conditioning of colour cues to food rewards in three individuals, we find a threshold ranging from 0.05 to 0.2 cd m(-2). Results are comparable to the two previously tested bird species. For tits, nest light conditions probably exceed that threshold, at least after sunrise. These results shed new light on the lively debate questioning the visual performance of cavity nesters and the evolutionary significance of egg and chick coloration. Although this needs further investigation, it is possible that blue tits exploit both colour and brightness cues when viewing their eggs, chicks or conspecifics in their nests.

  6. Light-Intensity-Induced Characterization of Elastic Constants and d33 Piezoelectric Coefficient of PLZT Single Fiber Based Transducers

    Directory of Open Access Journals (Sweden)

    Jiri Erhart

    2013-02-01

    Full Text Available Enhanced functionality of electro-optic devices by implementing piezoelectric micro fibers into their construction is proposed. Lanthanum-modified lead zirconate titanate (PLZT ceramics are known to exhibit high light transparency, desirable electro-optic properties and fast response. In this study PLZT fibers with a diameter of around 300 microns were produced by a thermoplastic processing method and their light-induced impedance and piezoelectric coefficient were investigated at relatively low light intensity (below 50 mW/cm2. The authors experimentally proved higher performance of light controlled microfiber transducers in comparison to their bulk form. The advantage of the high surface area to volume ratio is shown to be an excellent technique to design high quality light sensors by using fibrous materials. The UV absorption induced change in elastic constants of 3% and 4% for the piezoelectric coefficient d33.

  7. Light-intensity-induced characterization of elastic constants and d33 piezoelectric coefficient of PLZT single fiber based transducers.

    Science.gov (United States)

    Kozielski, Lucjan; Erhart, Jiri; Clemens, Frank Jörg

    2013-02-12

    Enhanced functionality of electro-optic devices by implementing piezoelectric micro fibers into their construction is proposed. Lanthanum-modified lead zirconate titanate (PLZT) ceramics are known to exhibit high light transparency, desirable electro-optic properties and fast response. In this study PLZT fibers with a diameter of around 300 microns were produced by a thermoplastic processing method and their light-induced impedance and piezoelectric coefficient were investigated at relatively low light intensity (below 50 mW/cm2). The authors experimentally proved higher performance of light controlled microfiber transducers in comparison to their bulk form. The advantage of the high surface area to volume ratio is shown to be an excellent technique to design high quality light sensors by using fibrous materials. The UV absorption induced change in elastic constants of 3% and 4% for the piezoelectric coefficient d(33).

  8. Proteomic study related to vascular connections in watermelon scions grafted onto bottle-gourd rootstock under different light intensities.

    Directory of Open Access Journals (Sweden)

    Sowbiya Muneer

    Full Text Available Although grafting is broadly used in the production of crops, no information is available about the proteins involved in vascular connections between rootstock and scion. Similarly, proteome changes under the light intensities widely used for grafted seedlings are of practical use. The objective of this study was to determine the proteome of vascular connections using watermelon (Citrullus vulgaris Schrad. 'Sambok Honey' and 'Speed' as the scion and bottle gourd (Lagenaria siceraria Stanld. 'RS Dongjanggun' as the rootstock grown under different light intensities (25, 50, 75 and 100 μmol m-2 s-1. Our proteomic analysis revealed 24 and 27 differentially expressed proteins in 'Sambok Honey' and 'Speed', respectively, under different light intensities. The identified proteins were largely involved in ion binding, amino acid metabolism, transcriptional regulation and defense response. The enhancement of ion-binding, transcriptional regulation, amino acid metabolism, and defense response proteins suggests a strengthening of the connection between the rootstock and scion under high light intensity. Indeed, the accumulation of key enzymes in the biological processes described above appears to play an important role in the vascular connections of grafted seedlings. Moreover, it appears that 100 μmol m-2 s-1 results in better protein expression responses in grafted seedlings.

  9. Proteomic study related to vascular connections in watermelon scions grafted onto bottle-gourd rootstock under different light intensities.

    Science.gov (United States)

    Muneer, Sowbiya; Ko, Chung Ho; Soundararajan, Prabhakaran; Manivnnan, Abinaya; Park, Yoo Gyeong; Jeong, Byoung Ryong

    2015-01-01

    Although grafting is broadly used in the production of crops, no information is available about the proteins involved in vascular connections between rootstock and scion. Similarly, proteome changes under the light intensities widely used for grafted seedlings are of practical use. The objective of this study was to determine the proteome of vascular connections using watermelon (Citrullus vulgaris Schrad.) 'Sambok Honey' and 'Speed' as the scion and bottle gourd (Lagenaria siceraria Stanld.) 'RS Dongjanggun' as the rootstock grown under different light intensities (25, 50, 75 and 100 μmol m-2 s-1). Our proteomic analysis revealed 24 and 27 differentially expressed proteins in 'Sambok Honey' and 'Speed', respectively, under different light intensities. The identified proteins were largely involved in ion binding, amino acid metabolism, transcriptional regulation and defense response. The enhancement of ion-binding, transcriptional regulation, amino acid metabolism, and defense response proteins suggests a strengthening of the connection between the rootstock and scion under high light intensity. Indeed, the accumulation of key enzymes in the biological processes described above appears to play an important role in the vascular connections of grafted seedlings. Moreover, it appears that 100 μmol m-2 s-1 results in better protein expression responses in grafted seedlings.

  10. Light-activation through indirect ceramic restorations: does the overexposure compensate for the attenuation in light intensity during resin cement polymerization?

    Directory of Open Access Journals (Sweden)

    Albano Luis Novaes Bueno

    2011-02-01

    Full Text Available OBJECTIVES: This study evaluated the effects of light exposure through simulated indirect ceramic restorations (SICR on hardness (KHN of dual-cured resin cements (RCs, immediately after light-activation and 24 h later. MATERIAL AND METHODS: Three dual-cured RCs were evaluated: Eco-Link (Ivoclar Vivadent, Rely X ARC (3M ESPE, and Panavia F (Kuraray Medical Inc.. The RCs were manipulated in accordance to the manufacturers' instructions and were placed into cylindrical acrylic matrixes (1-mm-thick and 4-mm diameter. The RC light-activation (Optilux 501; Demetron Kerr was performed through a glass slide for 120 s (control group, or through 2-mm or 4-mm thick SICRs (IPS Empress II; Ivoclar Vivadent. The specimens were submitted to KHN analysis immediately and 24 h after light-activation. The data obtained at the 2 evaluation intervals were submitted to 2-way ANOVA repeated measures and post-hoc Tukey's test (pre-set alpha of 5%. RESULTS: Lower KHN was observed when light-activation was performed through SICRs for Eco-Link at all evaluation intervals and for Rely X ARC 24 h later. For Panavia F, no significant difference in KHN was observed between control and experimental groups, regardless of evaluation interval. Most groups exhibited higher KHN after 24 h than immediately after light-activation, with the exception of Rely X ARC light-activated through SICR, as no significant difference in KHN was found between evaluation intervals. CONCLUSIONS: Light overexposure did not compensate for light intensity attenuation due to the presence of SICR when Rely X and Eco-Link were used. Although hardness of such RCs increased over a 24-h interval, the RCs subjected to light overexposure did not reach the hardness values exhibited after direct light exposure.

  11. The light intensity under which cells are grown controls the type of peripheral light-harvesting complexes that are assembled in a purple photosynthetic bacterium

    Energy Technology Data Exchange (ETDEWEB)

    Brotosudarmo, Tatas H. P. [Univ. of Glasgow, Scotland (United Kingdom). Inst. of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences; Collins, Aaron M. [Washington Univ., St. Louis, MO (United States). Depts. of Biology and Chemistry; Gall, Andrew [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA-Saclay), Gif-sur-Yvette (France). Inst. de Biologie et Technologies de Saclay et CNRS; Roszak, Aleksander W. [Univ. of Glasgow, Scotland (United Kingdom). Dept. of Chemistry, WestChem; Gardiner, Alastair T. [Univ. of Glasgow, Scotland (United Kingdom). Inst. of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences; Blankenship, Robert E. [Washington Univ., St. Louis, MO (United States). Depts. of Biology and Chemistry; Cogdell, Richard J. [Univ. of Glasgow, Scotland (United Kingdom). Inst. of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences

    2011-11-15

    The differing composition of LH2 (peripheral light-harvesting) complexes present in Rhodopseudomonas palustris 2.1.6 have been investigated when cells are grown under progressively decreasing light intensity. Analysis of the absorption spectra reveals there must be more than two types of LH2 complexes present. Purified HL (high-light) and LL (low-light) LH2 complexes have mixed apoprotein compositions. The HL complexes contain PucABa and PucABb apoproteins. The LL complexes contain PucABa, PucABd and PucBb-only apoproteins. This mixed apoprotein composition can explain their resonance Raman spectra.

  12. The light intensity under which cells are grown controls the type of peripheral light-harvesting complexes that are assembled in a purple photosynthetic bacterium.

    Science.gov (United States)

    Brotosudarmo, Tatas H P; Collins, Aaron M; Gall, Andrew; Roszak, Aleksander W; Gardiner, Alastair T; Blankenship, Robert E; Cogdell, Richard J

    2011-11-15

    The differing composition of LH2 (peripheral light-harvesting) complexes present in Rhodopseudomonas palustris 2.1.6 have been investigated when cells are grown under progressively decreasing light intensity. Detailed analysis of their absorption spectra reveals that there must be more than two types of LH2 complexes present. Purified HL (high-light) and LL (low-light) LH2 complexes have mixed apoprotein compositions. The HL complexes contain PucAB(a) and PucAB(b) apoproteins. The LL complexes contain PucAB(a), PucAB(d) and PucB(b)-only apoproteins. This mixed apoprotein composition can explain their resonance Raman spectra. Crystallographic studies and molecular sieve chromatography suggest that both the HL and the LL complexes are nonameric. Furthermore, the electron-density maps do not support the existence of an additional Bchl (bacteriochlorophyll) molecule; rather the density is attributed to the N-termini of the α-polypeptide.

  13. Light intensity-dependent modulation of chlorophyll b biosynthesis and photosynthesis by overexpression of chlorophyllide a oxygenase in tobacco.

    Science.gov (United States)

    Biswal, Ajaya K; Pattanayak, Gopal K; Pandey, Shiv S; Leelavathi, Sadhu; Reddy, Vanga S; Govindjee; Tripathy, Baishnab C

    2012-05-01

    Chlorophyll b is synthesized by the oxidation of a methyl group on the B ring of a tetrapyrrole molecule to a formyl group by chlorophyllide a oxygenase (CAO). The full-length CAO from Arabidopsis (Arabidopsis thaliana) was overexpressed in tobacco (Nicotiana tabacum) that grows well at light intensities much higher than those tolerated by Arabidopsis. This resulted in an increased synthesis of glutamate semialdehyde, 5-aminolevulinic acid, magnesium-porphyrins, and chlorophylls. Overexpression of CAO resulted in increased chlorophyll b synthesis and a decreased chlorophyll a/b ratio in low light-grown as well as high light-grown tobacco plants; this effect, however, was more pronounced in high light. The increased potential of the protochlorophyllide oxidoreductase activity and chlorophyll biosynthesis compensated for the usual loss of chlorophylls in high light. Increased chlorophyll b synthesis in CAO-overexpressed plants was accompanied not only by an increased abundance of light-harvesting chlorophyll proteins but also of other proteins of the electron transport chain, which led to an increase in the capture of light as well as enhanced (40%-80%) electron transport rates of photosystems I and II at both limiting and saturating light intensities. Although the quantum yield of carbon dioxide fixation remained unchanged, the light-saturated photosynthetic carbon assimilation, starch content, and dry matter accumulation increased in CAO-overexpressed plants grown in both low- and high-light regimes. These results demonstrate that controlled up-regulation of chlorophyll b biosynthesis comodulates the expression of several thylakoid membrane proteins that increase both the antenna size and the electron transport rates and enhance carbon dioxide assimilation, starch content, and dry matter accumulation.

  14. Versatile microscope-coupled high-intensity pulsed light source for high-speed cine photomicrography of microactuators

    Science.gov (United States)

    Krehl, Peter; Engemann, Stephan; Rembe, Christian; Hofer, Eberhard P.

    1997-05-01

    A compact high-intensity pulsed light source has been developed in order to match a microdynamic test facility for high-speed motion analysis of micromechanical components. The test stand encompasses a universal microscope Zeiss Axioplan, the new light source and an electronic ultra high- speed multiple framing camera Hadland Imacon 468. The light source consists of a narrow cylindrical Xe-filled discharge tube, thus providing a locally stable emission. Since the small-size flashlamp easily fits into a standard microscope lamphousing, it allows to maintain the advantages of Koehler illumination as well as switching to other types of lamphousings. The flash tube is operated via an artificial asymmetric transmission line and delivers a square light pulse with a flash duration of 110 microsecond(s) FWHM and a peak intensity of 50 Med. The light source illuminates the object uniformly within the interesting time window; image shuttering is provided in the camera by gated micro-channel- plate intensifiers. To test the efficiency of the total system for various standard visualization methods (transmitted light, reflected light and differential interference contrast), microscopic still images have been taken at magnification up to 500X and with exposure times down to 10 ns. In addition, two microscopic darkfield methods which provide a high contrast but a low light intensity of the image, have been selected to test their applicability down to an exposure time of 100 ns. Two examples for real-time cinematography of high-speed phenomena in microactuators are shown: the bouncing behavior of an electro-magnetic microrelay and the bubble/jet formation of a thermal ink jet printhead.

  15. Refining Sunrise/set Prediction Models by Accounting for the Effects of Refraction

    Science.gov (United States)

    Wilson, Teresa; Bartlett, Jennifer L.

    2016-01-01

    Current atmospheric models used to predict the times of sunrise and sunset have an error of one to four minutes at mid-latitudes (0° - 55° N/S). At higher latitudes, slight changes in refraction may cause significant discrepancies, including determining even whether the Sun appears to rise or set. While different components of refraction are known, how they affect predictions of sunrise/set has not yet been quantified. A better understanding of the contributions from temperature profile, pressure, humidity, and aerosols, could significantly improve the standard prediction. Because sunrise/set times and meteorological data from multiple locations will be necessary for a thorough investigation of the problem, we will collect this data using smartphones as part of a citizen science project. This analysis will lead to more complete models that will provide more accurate times for navigators and outdoorsman alike.

  16. Variation in pupil diameter in North American Gartersnakes (Thamnophis) is regulated by immersion in water, not by light intensity.

    Science.gov (United States)

    Fontenot, Clifford L

    2008-07-01

    A variable pupil generally regulates the amount of incoming light available for image formation on the retina. However, some of the semi-aquatic snakes (North American Gartersnakes, Thamnophis) that forage in relatively low light conditions reduce the pupil aperture in response to submergence underwater at the expense incoming light. Given that these snakes have all-cone retinas, reduction of incoming light because of pupillary constriction upon immersion seems counterintuitive. To test the effect of light and water on pupil aperture, three species of North American Gartersnakes (T. atratus, T. hammondii, and T. sirtalis) were exposed to nine light intensities in air and water. There was no effect of light on relative pupil aperture for any species. However, all three species showed a significant reduction in pupil aperture upon submergence underwater. The lack of a light response is surprising, and may be related to the method of accommodation in snakes. Snakes lack a ciliary muscle, and move the lens by constricting the pupil, which increases pressure in the posterior chamber and pushes the lens forward. Upon submergence, the snakes may be attempting to overcome the change in refractive index and defocus imposed by the water, by constricting the pupil. Thus, having the iris muscle involved in accommodation may preclude it from much of a light regulating function.

  17. Intense pulsed light annealing of copper zinc tin sulfide nanocrystal coatings

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Bryce A.; Smeaton, Michelle A.; Holgate, Collin S.; Trejo, Nancy D.; Francis, Lorraine F., E-mail: francis@umn.edu; Aydil, Eray S., E-mail: aydil@umn.edu [Department of Chemical Engineering and Materials Science, University of Minnesota, 151 Amundson Hall, 421 Washington Avenue SE, Minneapolis, Minnesota 55455 (United States)

    2016-09-15

    A promising method for forming the absorber layer in copper zinc tin sulfide [Cu{sub 2}ZnSnS{sub 4} (CZTS)] thin film solar cells is thermal annealing of coatings cast from dispersions of CZTS nanocrystals. Intense pulsed light (IPL) annealing utilizing xenon flash lamps is a potential high-throughput, low-cost, roll-to-roll manufacturing compatible alternative to thermal annealing in conventional furnaces. The authors studied the effects of flash energy density (3.9–11.6 J/cm{sup 2}) and number of flashes (1–400) during IPL annealing on the microstructure of CZTS nanocrystal coatings cast on molybdenum-coated soda lime glass substrates (Mo-coated SLG). The annealed coatings exhibited cracks with two distinct linear crack densities, 0.01 and 0.2 μm{sup −1}, depending on the flash intensity and total number of flashes. Low density cracking (0.01 μm{sup −1}, ∼1 crack per 100 μm) is caused by decomposition of CZTS at the Mo-coating interface. Vapor decomposition products at the interface cause blisters as they escape the coating. Residual decomposition products within the blisters were imaged using confocal Raman spectroscopy. In support of this hypothesis, replacing the Mo-coated SLG substrate with quartz eliminated blistering and low-density cracking. High density cracking is caused by rapid thermal expansion and contraction of the coating constricted on the substrate as it is heated and cooled during IPL annealing. Finite element modeling showed that CZTS coatings on low thermal diffusivity materials (i.e., SLG) underwent significant differential heating with respect to the substrate with rapid rises and falls of the coating temperature as the flash is turned on and off, possibly causing a build-up of tensile stress within the coating prompting cracking. Use of a high thermal diffusivity substrate, such as a molybdenum foil (Mo foil), reduces this differential heating and eliminates the high-density cracking. IPL annealing in presence of sulfur

  18. Effectiveness of Intense Pulsed Light treatment in solar lentigo: a retrospective study

    Directory of Open Access Journals (Sweden)

    İlgen Ertam

    2014-03-01

    Full Text Available Intense Pulsed Light (IPL; is a light system of 500-1200 nm wavelength which is used for the treatment of hair removal, hyperpigmentation, non-ablative skin resurfacing and superficial vascular lesions. The mechanism of action is thought to be the focal epidermal coagulation due to selective photothermolysis in the epidermal keratinocytes and melanocytes. A variety of laser systems can be used in the treatment of lsolar entigo. The aim of this study is to investigate the effectiveness of IPL in solar lentigo. Materials and Methods: The archives of Cosmetology Unit retrospectively reviewed for the patients with the diagnosis of solar lentigo from March 2007 to November 2010. There were 139 files of patients who were diagnosed as solar lentigo clinically and dermoscopically and treated by IPL (L900 a & m IPL. Informed consent was taken from all patients. Among them, 42 patients who had come to controls regularly and had photographed before and after treatment included into the study. Results: A total of 52 lesions of 42 female and 1 male patient included into the study. Patients’ mean age was 42±9.6 years, ranging between 33 to 88. Of the lesions, 27 lesions(51.9% were on cheek, 7 lesions (13.5% were on zygoma, 6 lesions (11.5% were on chin, 4 lesions (7.7% were on hands, 4 lesions (7.7% were on forehead, 2 lesions(3.8% were on nose, 2 lesions (3.8% were on forearm. The mean number of sessions was 3.28 ranging between 1 and 7. After treatment, improvement was over 75% in 57,7% lesions, 50-75% in 17.3% of the lesions, 25-50% in 17.3% of the lesions, under 25% in 7.7% of the lesions. Conclusion: According to the results of our work, IPL can be accepted as an effective, cheap and safety method in terms of its side effects in treatment of solar lentigo.

  19. Generation of two-lobe light fields with a rotating intensity distribution under propagation for single emitter spectroscopy

    Science.gov (United States)

    Volostnikov, V. G.; Vorontsov, E. N.; Kotova, S. P.; Losevsky, N. N.; Prokopova, D. V.; Razueva, E. V.; Samagin, S. A.

    2016-12-01

    The paper outlines the results of studies on the generation of two-lobe light fields with the intensity distribution rotating during the field propagation. Such fields are needed to determine the depth of bedding of single emitters in spectral studies of substance properties. On the base of the spiral beam optics, the phase distributions were obtained for the synthesis of two-lobe fields with different speeds of rotation of the intensity distribution. The light fields have been formed by using a liquid-crystal spatial phase modulator HOLOEYE HEO-1080P. The influence of the illuminating beam parameters and the aberrations of the system on the quality of the formed light field was also studied.

  20. Generation of two-lobe light fields with a rotating intensity distribution under propagation for single emitter spectroscopy

    Directory of Open Access Journals (Sweden)

    Volostnikov V.G.

    2017-01-01

    Full Text Available The paper outlines the results of studies on the generation of two-lobe light fields with the intensity distribution rotating during the field propagation. Such fields are needed to determine the depth of bedding of single emitters in spectral studies of substance properties. On the base of the spiral beam optics, the phase distributions were obtained for the synthesis of two-lobe fields with different speeds of rotation of the intensity distribution. The light fields have been formed by using a liquid-crystal spatial phase modulator HOLOEYE HEO-1080P. The influence of the illuminating beam parameters and the aberrations of the system on the quality of the formed light field was also studied.

  1. The effects of taurine on vigabatrin, high light intensity and mydriasis induced retinal toxicity in the pigmented rat.

    Science.gov (United States)

    Rasmussen, Allan D; Truchot, Nathalie; Pickersgill, Nigel; Thale, Zia Irene; Rosolen, Serge G; Botteron, Catherine

    2015-01-01

    The overall purpose of this study was to establish a model that may be used for examining the effect of Vigabatrin-induced retinal toxicity in pigmented rats, and subsequently examine the possible effects of taurine on the retinal toxicity. In the first part of the study, pigmented Long Evans rats were subjected to combinations of induced mydriasis, low/high light intensities (40/2000 lx) and oral administration of near-MTD (Maximum Tolerated Dose) doses (200 mg/kg/day) of Vigabatrin for up to 6 weeks. The combination of mydriasis and high light intensity applied to Long Evans rats resulted in retinal damage that was increased by the administration of Vigabatrin. In the second part of the study Long Evans rats were subjected to combinations of induced mydriasis and high/low light intensity (40/2000 lx) while being orally administered low (30 mg/kg/day) or high (200 mg/kg/day) doses of Vigabatrin for up to 6 weeks. In addition, selected groups of animals were administered taurine via the drinking water (20 mg/ml), resulting in systemic taurine concentrations of approximately threefold the endogenous concentration. The combined results of the studies demonstrate that retinal damage can be induced in pigmented animals when combining mydriasis and high light intensity. Retinal damage was functionally evaluated by electroretinography (ERG), then confirmed by histopathology. While depending on mydriasis and high light intensity, administration of Vigabatrin increased the retinal toxicity and resulted in the formation of rosette-like structures in the retina in a dose-related manner. Administration of taurine did not alleviate the Vigabatrin-induced retinal toxicity, as demonstrated either functionally by ERG or morphologically, although systemic concentrations of 3-fold the endogenous levels were reached, and it was thus not possible to demonstrate a protective effect of taurine in these pigmented animals. Copyright © 2014 Elsevier GmbH. All rights reserved.

  2. MEASURING COLOR HUE IN ‘SUNRISE SOLO’ PAPAYA USING A FLATBED SCANNER

    Directory of Open Access Journals (Sweden)

    THIAGO DE PAULA OLIVEIRA

    Full Text Available ABSTRACT Color hue is a variable frequently used postharvest to assess the physiological maturity of various fruits. In general, mean color hue is quantified by visual techniques, but this method, based on human grading, is tedious and may be erroneous. The color of fruit peel is frequently determined at four points randomly distributed on the equatorial region of a fruit, but this practice can lead to biased results because these points represent the equatorial region only and not the total area of the fruit peel. Consequently, this bias is not due to equipment measurement errors, but to the bias in the sampling process of the points on the fruit epidermis. An alternative to such methods is the digital image which provides information about all regions of the fruit peel, and results in a more accurate mean hue. However, this technique requires calibration to correct the values of luminance, hue and intensity obtained through the scanner. This calibration can be performed from color patterns such that each pattern is assessed by means of a scanner and a colorimeter. Thus, an experiment was conducted using 297 color patterns based on the Munssel color chart for plant tissue. The results showed that the scanner could be used as a device for color assessment where the determination coefficients were above 0.9 for all color components. Next, a second experiment was conducted in order to compare the scanner and colorimeter methodologies. For this, we used a papaya fruit, cv. Sunrise Solo, which was assessed by these two devices for a period of 19 days. The results showed that the image analysis measures have a different mean hue when compared with the mean hue obtained by the method using a colorimeter. Therefore, it is recommended that digital image analysis be used for the evaluation of the hue of fruit peel color when fruit presents non-uniform coloration.

  3. Absolute phase recovery in structured light illumination systems: Sinusoidal vs. intensity discrete patterns

    Science.gov (United States)

    Porras-Aguilar, Rosario; Falaggis, Konstantinos

    2016-09-01

    Structured light illumination is a well-established technology for noncontact 3D surface measurements. A common challenge in those systems is to obtain the absolute surface information using few measurement frames. This work discusses techniques based on the projection of multiple sinusoidal fringe patterns with different fringe period, as well as the projection of intensity discrete Gray Code and grey-level coded patterns. The use of sinusoidal multi-frequency techniques has been since years an on-going area of research, where various algorithms have been developed based on beats, look-up tables, or number-theoretical approaches. This work shows that a related technique, the so-called algebraic reconstruction technique that is borrowed from the area of multi-wavelength interferometry can be used for this purpose. This approach provides a robust analytical solution to the phase-unwrapping problem. However, this work argues that despite these advances, the acquisition of additional phase maps obtained with different fringe periods requires too many measurement frames, and hence is inefficient. Motivated by that, this work proposes a new grey level coding scheme that uses only few measurement frames, overcomes typical defocus errors, and has an error detecting feature. The latter feature makes the need of separate error detecting algorithms obsolete. This so-called closed-loop space filling curve can be implemented with an arbitrary number of N grey-levels enabling to code up to (2N) code-words. The performance of this so-called closed-loop space filling curve is demonstrated using experimental data.

  4. The success of the cyanobacterium Cylindrospermopsis raciborskii in freshwaters is enhanced by the combined effects of light intensity and temperature

    Directory of Open Access Journals (Sweden)

    Sylvia Bonilla

    2016-06-01

    Full Text Available Toxic cyanobacterial blooms in freshwaters are thought to be a consequence of the combined effects of anthropogenic eutrophication and climate change. It is expected that climate change will affect water mixing regimes that alter the water transparency and ultimately the light environment for phytoplankton. Blooms of the potentially toxic cyanobacterium Cylindrospermopsis raciborskii are expanding from tropical towards temperate regions. Several hypotheses have been proposed to explain this expansion, including an increase in water temperature due to climate change and the high phenotypic plasticity of the species that allows it to exploit different light environments. We performed an analysis based on eight lakes in tropical, subtropical and temperate regions to examine the distribution and abundance of C. raciborskii in relation to water temperature and transparency. We then conducted a series of short-term factorial experiments that combined three temperatures and two light intensity levels using C. raciborskii cultures alone and in interaction with another cyanobacterium to identify its growth capacity. Our results from the field, in contrast to predictions, showed no differences in dominance (>40% to the total biovolume of C. raciborskii between climate regions. C. raciborskii was able to dominate the phytoplankton in a wide range of light environments (euphotic zone = 1.5 to 5 m, euphotic zone/mixing zone ratio <0.5 to >1.5. Moreover, C. raciborskii was capable of dominating the phytoplankton at low temperatures (<15°C. Our experimental results showed that C. raciborskii growing in interaction was enhanced by the increase of the temperature and light intensity. C. raciborskii growth in high light intensities and at a wide range of temperatures, suggests that any advantage that this species may derive from climate change that favors its dominance in the phytoplankton is likely due to changes in the light environment rather than changes in

  5. The impact of architectural design upon the environmental sound and light exposure of neonates who require intensive care: an evaluation of the Boekelheide Neonatal Intensive Care Nursery.

    Science.gov (United States)

    Stevens, D C; Akram Khan, M; Munson, D P; Reid, E J; Helseth, C C; Buggy, J

    2007-12-01

    To evaluate the differences in environmental sound, illumination and physiological parameters in the Boekelheide Neonatal Intensive Care Unit (BNICU), which was designed to comply with current recommendations and standards, as compared with a conventional neonatal intensive care unit (CNICU). Prospectively designed observational study. Median sound levels in the unoccupied BNICU (37.6 dBA) were lower than the CNICU (42.1 dBA, P<0.001). Median levels of minimum (6.4 vs 48.4 lux, P<0.05) and maximum illumination (357 vs 402 lux, P<0.05) were lower in the BNICU. A group of six neonates delivered at 32 weeks gestation showed significantly less periodic breathing (14 vs 21%) and awake time (17.6 vs 29.3%) in the BNICU as compared to the CNICU. Light and sound were both significantly reduced in the BNICU. Care in the BNICU was associated with improved physiological parameters.

  6. Dose-response relationship for light intensity and ocular and electroencephalographic correlates of human alertness

    Science.gov (United States)

    Cajochen, C.; Zeitzer, J. M.; Czeisler, C. A.; Dijk, D. J.

    2000-01-01

    Light can elicit both circadian and acute physiological responses in humans. In a dose response protocol men and women were exposed to illuminances ranging from 3 to 9100 lux for 6.5 h during the early biological night after they had been exposed to dose response curve. Half of the maximum alerting response to bright light of 9100 lux was obtained with room light of approximately 100 lux. This sensitivity to light indicates that variations in illuminance within the range of typical, ambient, room light (90-180 lux) can have a significant impact on subjective alertness and its electrophysiologic concomitants in humans during the early biological night.

  7. The effect of visible-light intensity on shape evolution and antibacterial properties of triangular silver nanostructures

    Science.gov (United States)

    Ashkarran, Ali Akbar

    2016-08-01

    Triangular silver nanostructures represent a novel class of nanomaterials with tunable surface plasmon resonance (SPR). By controlling the size and geometry of these structures, their SPR peaks could be tuned from the visible to the near-infrared region with numerous applications in optoelectronic, sensors, nanomedicine and specially cancer diagnosis and treatment. In this study, triangular silver nanostructures were prepared by photoinducing of spherical silver nanoparticles (NPs) with an average diameter of 10 nm. Transmission electron microscopy (TEM) and ultra violet visible (UV-Vis) spectroscopy were used to characterize silver triangles. We have found that uniform triangular silver nanostructures can be obtained using an appropriate visible-light illumination to the primary spherical silver NPs. TEM images indicated that formation of triangular structures depends on the intensity of light source. The effect of intensity of visible-light source on the geometry and size distribution of silver triangles was investigated. It was found that formation of triangular structures in addition to their size and shape evolution strongly depends on the intensity of the light illumination. Furthermore, a comparative study on the antibacterial activities of silver triangles of different sizes reveals that silver triangles experience a size-dependent interaction with the gram-negative Escherichia coli bacteria.

  8. THE METHOD OF CAR HEADLIGHTS LUMINOUS INTENSITY MEASURING FOR NON-POINT SOURCES OF LIGHT

    Directory of Open Access Journals (Sweden)

    A. Kupko

    2015-12-01

    Full Text Available It is shown that the measurements of luminous intensity of car headlights luminous intensity for non-point sources have pecularities. A simplified method for correction the luminous intensity at various distances is developed. The applicability of the given method with possible measurement errors is studied. The results were obtained, using a stand of the National Scientific Center “Institute of Metroligy”.

  9. Effects of age, strain, and illumination intensity on activity and self-selection of light-dark schedules in mice.

    Science.gov (United States)

    Wax, T M

    1977-02-01

    Young and senescent albino A/J mice, pigmented C57BL/6J pure inbred mice, and their hybrid F1S were tested under low or high illumination intensities to observe differences in self-selected wheel running, bar pressing, and durations of light and dark over time. The animals (N = 120) were always allowed ad lib access to food, water, running wheel, and bar-press levers. During the pre- and postexperimental phases, the mice were kept under a standard 12:12 hr light/dark cycle; during the experimental phase, however, they were allowed to select their own light and dark schedules by pressing on either of two accessible bars, one light contingent and the other dark contingent. Measures of general running and bar-pressing activities, motivational aspects of illumination change and intensity preferences, time-series analyses of periodicities, power ratios, and significant other multiples were obtained from the subjects during a total of three experimental phases. Age differences were found for most of the measures studied and in general showed declines in activity levels, inccreases in motivation to change illumination conditions, lengthening of activity cycles (slower periods), and decreases in the strengths of the oscillations underlying these behaviors as well as an increase in the number of other periodic components in old mice relative to young. Genetic group and illumination-intensity differences were also found, and the results are discussed in light of theories concerning illumination preference and stimulus change, earlier work involving voluntary light selection behavior, and aging studies.

  10. Intensity of bitterness of processed yerba mate leaves originated in two contrasted light environments

    Directory of Open Access Journals (Sweden)

    Miroslava Rakocevic

    2008-06-01

    Full Text Available The bitterness intensity of beverage prepared from the leaves produced on the males and females of yerba mate (Ilex paraguariensis, grown in the forest understory and monoculture, was evaluated. The leaves were grouped by their position (in the crown and on the branch tips and by the leaf age. The leaf gas exchange, leaf temperature and photosynthetic photon flux density were observed. Inter and intra-specific competition for light and self-shading showed the same effect on yerba mate beverage taste. All the shading types resulted in bitterer taste of the processed yerba mate leaves compared to the leaves originated under the direct sun exposure. The leaves from the plants grown in the monoculture showed less bitterness than those grown in the forest understory. This conclusion was completely opposite to the conventionally accepted paradigm of the yerba mate industries. The leaves from the tips (younger leaves of the plants grown in the monoculture resulted a beverage of softer taste; the males produced less bitter leaves in any light environment (forest understory or in the crown in monoculture. The taste was related to the photosynthetic and transpiration rate, and leaf temperature. Stronger bitterness of the leaves provided from the shade conditions was related to the decreased leaf temperature and transpiration in the diurnal scale.Mediu-se a intensidade de amargor da bebida preparada a partir de folhas da erva-mate (Ilex paraguariensis de diversas idades, situadas em duas posições na copa (interior e ponteiras, produzidas por plantas masculinas e femininas cultivadas na floresta antropizada e em monocultura. As trocas gasosas foliares, a temperatura de folhas e a densidade de fluxo de fótons fotossinteticamente ativos também foram medidas. Com isso verificou-se que a idéia corrente de que o sombreamento está diretamente relacionado ao sabor suave do chimarrão é completamente equivocada, já que as competições inter- e intra

  11. Improvement of luminous intensity of InGaN light emitting diodes grown on hemispherical patterned sapphire

    Science.gov (United States)

    Lee, Jae-Hoon; Oh, Jeong-Tak; Park, Jin-Sub; Kim, Je-Won; Kim, Yong-Chun; Lee, Jeong-Wook; Cho, Hyung-Koun

    2006-06-01

    To improve the external quantum efficiency, high quality GaN film was grown on hemispherical patterned sapphire by controlling the V/III ratio during the initial growth stage. The luminous intensity of white flash light emitting diode (LED) grown on hemispherical patterned sapphire (HPS) was estinated to be 5.8 cd at a forward current of 150 mA, which is improved by 20% more than that of LED grown on conventional sapphire substrate. The improvement of luminous intensity was explained by considering not only an increase of the extraction efficiency via the suppressed total internal reflection at the corrugated interface but also a decrease of dislocation density.

  12. The Russian Federation and the Arctic Sunrise Case: Hot Pursuit and Other Issues under the LOSC

    NARCIS (Netherlands)

    Oude Elferink, A.G.|info:eu-repo/dai/nl/090439309

    2016-01-01

    The Arctic Sunrise case was brought unilaterally by the Netherlands against the Russian Federation under the United Nations Convention on the Law of the Sea on October 4, 2013 after the Russian Federation had boarded the vessel and arrested it and its crew. The article discusses the subsequent

  13. The Sunrise project: An R&D project for a national information infrastructure prototype

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Juhnyoung

    1995-02-01

    Sunrise is a Los Alamos National Laboratory (LANL) project started in October 1993. It is intended to a prototype National Information Infrastructure (NII) development project. A main focus of Sunrise is to tie together enabling technologies (networking, object-oriented distributed computing, graphical interfaces, security, multimedia technologies, and data mining technologies) with several specific applications. A diverse set of application areas was chosen to ensure that the solutions developed in the project are as generic as possible. Some of the application areas are materials modeling, medical records and image analysis, transportation simulations, and education. This paper provides a description of Sunrise and a view of the architecture and objectives of this evolving project. The primary objectives of Sunrise are three-fold: (1) To develop common information-enabling tools for advanced scientific research and its applications to industry; (2) To enhance the capabilities of important research programs at the Laboratory; and (3) To define a new way of collaboration between computer science and industrially relevant research.

  14. Light-intensity-dependent expression of Lhc gene family encoding light-harvesting chlorophyll-a/b proteins of photosystem II in Chlamydomonas reinhardtii.

    Science.gov (United States)

    Teramoto, Haruhiko; Nakamori, Akira; Minagawa, Jun; Ono, Taka-aki

    2002-09-01

    Excessive light conditions repressed the levels of mRNAs accumulation of multiple Lhc genes encoding light-harvesting chlorophyll-a/b (LHC) proteins of photosystem (PS)II in the unicellular green alga, Chlamydomonas reinhardtii. The light intensity required for the repression tended to decrease with lowering temperature or CO(2) concentration. The responses of six LhcII genes encoding the major LHC (LHCII) proteins and two genes (Lhcb4 and Lhcb5) encoding the minor LHC proteins of PSII (CP29 and CP26) were similar. The results indicate that the expression of these Lhc genes is coordinately repressed when the energy input through the antenna systems exceeds the requirement for CO(2) assimilation. The Lhc mRNA level repressed under high-light conditions was partially recovered by adding the electron transport inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea, suggesting that redox signaling via photosynthetic electron carriers is involved in the gene regulation. However, the mRNA level was still considerably lower under high-light than under low-light conditions even in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea. Repression of the Lhc genes by high light was prominent even in the mutants deficient in the reaction center(s) of PSII or both PSI and PSII. The results indicate that two alternative processes are involved in the repression of Lhc genes under high-light conditions, one of which is independent of the photosynthetic reaction centers and electron transport events.

  15. Effect of light intensity on partitioning of photosynthetic electron transport to photorespiration in four subtropical forest plants

    Institute of Scientific and Technical Information of China (English)

    林植芳; 彭长连; 孙梓建; 林桂珠

    2000-01-01

    Photosynthetic rate (Pn) and the partitioning of noncyclic photosynthetic electron transport to photorespiration (Jo) in seedlings of four subtropical woody plants growing at three light intensities were studied in the summer time by measurements of chlorophyll fluorescence and CO2 exchange. Except Schima superba, an upper canopy tree species, the tree species Castanopsis fissa and two understory shrubs Psychotria rubra, Ardisia quinquegona had the highest Pn at 36% of sunlight intensity. The total photosynthetic electron transport rate (JF) and the ratio of Jo/JF were elevated in leaves under full sunlight. Jo/JF ratio reached 0.5-0.6 and coincided with the increasing of oxygenation rate of Rubisco (Vo), the activity of glycolate oxidase and photorespiration rate at full sunlight. It is suggested that an increasing partitioning proportion of photosynthetic electron transport to photorespiration might be one of the protective regulation mechanisms in forest plant under strong summer light and high tempe

  16. Effect of light intensity on partitioning of photosynthetic electron transport to photorespiration in four subtropical forest plants

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Photosynthetic rate (Pn) and the partitioning of noncyclic photosynthetic electron transport to photorespiration (Jo) in seedlings of four subtropical woody plants growing at three light intensities were studied in the summer time by measurements of chlorophyll fluorescence and CO2 exchange. Except Schima superba, an upper canopy tree species, the tree species Castanopsis fissa and two understory shrubs Psychotria rubra, Ardisia quinquegona had the highest Pn at 36% of sunlight intensity. The total photosynthetic electron transport rate (JF) and the ratio of Jo/JF were elevated in leaves under full sunlight. Jo/JF ratio reached 0.5-0.6 and coincided with the increasing of oxygenation rate of Rubisco (Vo), the activity of glycolate oxidase and photorespiration rate at full sunlight. It is suggested that an increasing partitioning proportion of photosynthetic electron transport to photorespiration might be one of the protective regulation mechanisms in forest plant under strong summer light and high temperature conditions.

  17. Effect of illumination intensity and light application time on secondary organic aerosol formation from the photooxidation of α-pinene

    Institute of Scientific and Technical Information of China (English)

    LIU Xianyun; ZHANG Weijun; HUANG Mingqiang; WANG Zhenya; HAO Liqing; ZHAO Wenwu

    2009-01-01

    Secondary organic aerosol (SOA) formation from hydroxyl radical (OH·) initiated photooxidation of α-pinene was investigated in a home-made smog chamber. The size distribution of SOA particles was measured using aerodynamic particle sizer spectrometer. The effect of illumination intensity and light application time on SOA formation for α-pinene was evaluated. Experimental results show that the concentration of SOA particles increased significantly with the increasing of illumination intensity, and the light application time, the concentration, and the size of SOA particals were also increased. The factors influencing the formation of SOA were also discussed. This atricle compared the effect of α-pinene with that of toluene, and discussed the contribution of α-pinene to SOA formation.

  18. High-intensity urban light installation dramatically alters nocturnal bird migration.

    Science.gov (United States)

    Van Doren, Benjamin M; Horton, Kyle G; Dokter, Adriaan M; Klinck, Holger; Elbin, Susan B; Farnsworth, Andrew

    2017-10-02

    Billions of nocturnally migrating birds move through increasingly photopolluted skies, relying on cues for navigation and orientation that artificial light at night (ALAN) can impair. However, no studies have quantified avian responses to powerful ground-based light sources in urban areas. We studied effects of ALAN on migrating birds by monitoring the beams of the National September 11 Memorial & Museum's "Tribute in Light" in New York, quantifying behavioral responses with radar and acoustic sensors and modeling disorientation and attraction with simulations. This single light source induced significant behavioral alterations in birds, even in good visibility conditions, in this heavily photopolluted environment, and to altitudes up to 4 km. We estimate that the installation influenced ≈1.1 million birds during our study period of 7 d over 7 y. When the installation was illuminated, birds aggregated in high densities, decreased flight speeds, followed circular flight paths, and vocalized frequently. Simulations revealed a high probability of disorientation and subsequent attraction for nearby birds, and bird densities near the installation exceeded magnitudes 20 times greater than surrounding baseline densities during each year's observations. However, behavioral disruptions disappeared when lights were extinguished, suggesting that selective removal of light during nights with substantial bird migration is a viable strategy for minimizing potentially fatal interactions among ALAN, structures, and birds. Our results also highlight the value of additional studies describing behavioral patterns of nocturnally migrating birds in powerful lights in urban areas as well as conservation implications for such lighting installations.

  19. The sensory quality of meat, game, poultry, seafood and meat products as affected by intense light pulses: a systematic review

    OpenAIRE

    2015-01-01

    The effect of intense light pulses (ILP) on sensory quality of 16 different varieties of meat, meat products, game, poultry and seafood are reviewed. Changes induced by ILP are animal species, type of meat product and fluences applied dependent. ILP significantly deteriorates sensory quality of cooked meat products. It causes less change in the sensory properties of dry cured than cooked meat products while fermented sausage is least affected. The higher fluence applied significantly changes ...

  20. Photo-enhanced toxicity of fluoranthene to Gulf of Mexico marine organisms at different larval ages and ultraviolet light intensities.

    Science.gov (United States)

    Finch, Bryson E; Stubblefield, William A

    2016-05-01

    Significant increases in toxicity have been observed as a result of polycyclic aromatic hydrocarbon (PAH) absorption of ultraviolet (UV) radiation in aquatic organisms. Early life stage aquatic organisms are predicted to be more susceptible to PAH photo-enhanced toxicity as a result of their translucence and tendency to inhabit shallow littoral or surface waters. The objective of the present study was to evaluate the sensitivity of varying ages of larval mysid shrimp (Americamysis bahia), inland silverside (Menidia beryllina), sheepshead minnow (Cyprinodon variegatus), and Gulf killifish (Fundulus grandis) to photo-enhanced toxicity and to examine the correlation between photo-enhanced toxicity and organism pigmentation. Organisms were exposed to fluoranthene and artificial UV light at different larval ages and results were compared using median lethal concentrations (LC50s) and the lethal time-to-death (LT50s). In addition, a high UV light intensity, short-duration (4-h) experiment was conducted at approximately 24 W/m(2) of ultraviolet radiation A (UV-A) and compared with a low-intensity, long-duration (12-h) experiment at approximately 8 W/m(2) of UV-A. The results indicated decreased toxicity with increasing age for all larval organisms. The amount of organism pigmentation was correlated with observed LC50 and LT50 values. High-intensity short-duration exposure resulted in greater toxicity than low-intensity long-duration UV treatments for mysid shrimp, inland silverside, and sheepshead minnow. Data from these experiments suggest that toxicity is dependent on age, pigmentation, UV light intensity, and fluoranthene concentration.

  1. Intensive Plasmonic Flash Light Sintering of Copper Nanoinks Using a Band-Pass Light Filter for Highly Electrically Conductive Electrodes in Printed Electronics.

    Science.gov (United States)

    Hwang, Yeon-Taek; Chung, Wan-Ho; Jang, Yong-Rae; Kim, Hak-Sung

    2016-04-06

    In this work, an intensive plasmonic flash light sintering technique was developed by using a band-pass light filter matching the plasmonic wavelength of the copper nanoparticles. The sintering characteristics, such as resistivity and microstructure, of the copper nanoink films were studied as a function of the range of the wavelength employed in the flash white light sintering. The flash white light irradiation conditions (e.g., wavelength range, irradiation energy, pulse number, on-time, and off-time) were optimized to obtain a high conductivity of the copper nanoink films without causing damage to the polyimide substrate. The wavelength range corresponding to the plasmonic wavelength of the copper nanoparticles could efficiently sinter the copper nanoink and enhance its conductivity. Ultimately, the sintered copper nanoink films under optimal light sintering conditions showed the lowest resistivity (6.97 μΩ·cm), which was only 4.1 times higher than that of bulk copper films (1.68 μΩ·cm).

  2. Effect of Light Intensity for Optimum Biomass and Lipid Production from Scenedesmus dimorphus (Turpin) Kützing

    Science.gov (United States)

    Kurniawati, F. N.; Mahajoeno, E.; Sunarto; Sari, S. L. A.

    2017-07-01

    One source of alternative energy substitute for petroleum raw materials is renewable vegetable oils known as biodiesel. Biodiesel can be produced from microalgae, since it was more efficient and environmentally friendly. Scenedesmus dimorphus (Turpin) Kützing was developed as a source of biodiesel since it had potential of high lipid production. The aims of this research were to know the rate of growth of Scenedesmus dimorphus in different lighting and the optimimum light intensity for biomass and lipid production. This research used a completely randomized design consisting of 3 treatments with 3 replications. Treatments in this research were the light intensity, i.e. 7,500, 10,000, and 12,500 lux. Scenedesmus dimorphus was grew in Bold’s Basal Medium (BBM). Parameters observed in this research were the cell number, biomass and lipid production of S. dimorphus. Data were analyzed by ANOVA followed by DMRT 5%. The results showed that the optimum growth rate of S. dimorphus was in the intensity of 12,500 lux that was 100.80 x 106 cells.ml-1. The optimum production of biomass and lipids was in treatment 12,500 lux i.e; 1.1407 g.L-1 and 0.2520 g.L-1 (22.28% dry weight).

  3. High light intensity plays a major role in emergence of population level variation in Arabidopsis thaliana along an altitudinal gradient.

    Science.gov (United States)

    Tyagi, Antariksh; Yadav, Amrita; Tripathi, Abhinandan Mani; Roy, Sribash

    2016-05-23

    Environmental conditions play an important role in the emergence of genetic variations in natural populations. We identified genome-wide patterns of nucleotide variations in the coding regions of natural Arabidopsis thaliana populations. These populations originated from 700 m to 3400 m a.m.s.l. in the Western Himalaya. Using a pooled RNA-Seq approach, we identified the local and global level population-specific SNPs. The biological functions of the SNP-containing genes were primarily related to the high light intensity prevalent at high-altitude regions. The novel SNPs identified in these genes might have arisen de novo in these populations. In another approach, the FSTs of SNP-containing genes were correlated with the corresponding climatic factors. 'Radiation in the growing season' was the only environmental factor found to be strongly correlated with the gene-level FSTs. In both the approaches, the high light intensity was identified as the primary abiotic stress associated with the variations in these populations. The differential gene expression analysis between field and controlled condition grown plants also showed high light intensity as the primary abiotic stress, particularly for the high altitude populations. Our results provide a genome-wide perspective of nucleotide variations in populations along altitudinal gradient and their putative role in emergence of these variations.

  4. Removal of Low-Molecular Weight Aldehydes by Selected Houseplants under Different Light Intensities and CO2 Concentrations

    Directory of Open Access Journals (Sweden)

    Jian Li

    2016-11-01

    Full Text Available The removal of five low-molecular weight aldehydes by two houseplants (Schefflera octophylla (Lour. Harms and Chamaedorea elegans were investigated in a laboratory simulation environment with short-term exposure to different low light intensities and CO2 concentrations. Under normal circumstances, the C1–C5 aldehyde removal rates of Schefflera octophylla (Lour. Harms and Chamaedorea elegans (Lour. Harms ranged from 0.311 μmol/m2/h for valeraldehyde to 0.677 μmol/m2/h for formaldehyde, and 0.526 μmol/m2/h for propionaldehyde to 1.440 μmol/m2/h for formaldehyde, respectively. However, when the light intensities varied from 0 to 600 lx, a significant correlation between the aldehyde removal rate and the light intensity was found. Moreover, the CO2 experiments showed that the total aldehyde removal rates of Schefflera octophylla (Lour. Harms and Chamaedorea elegans (Lour. Harms decreased 32.0% and 43.2%, respectively, with increasing CO2 concentrations from 350 ppmv to 1400 ppmv. This might be explained by the fact that the excessive CO2 concentration decreased the stomatal conductance which limited the carbonyl uptake from the stomata.

  5. The Comparison of Experimental and Analytical Study of the Gaussian IntensityDistribution for Light Emitting Diodes Beam

    Directory of Open Access Journals (Sweden)

    Harry Ramza

    2012-01-01

    Full Text Available Problem statement: Wireless communication using white Light Emitting Diodes (LEDs is the latest research field for next-generation communication. This study studies the comparison of Gaussian intensity distribution of the white LED using experimental and analytical method. The white LEDs are conducted to transmit an audio signal to the receiver. The receiver circuit consist of solar cell connected to the speaker to recover the audio signal. From the comparison of experimental and analytical data, the Gaussian plot of experimental data is steeper than the analytical data, meaning that the LED has small-divergence beam. Conclusion/Recommendations: The output voltage of experimental works decrease exponentially with the distance whiles the Full Width Half Maximum (FWHM value increase exponentially with the distance. The gradual increment and decrement of the analytical signal can be applicable to visible light communication implementation as such light source can cover wide area for signal transmission.

  6. Effect of high wavelengths low intensity light during dark period on physical exercise performance, biochemical and haematological parameters of swimming rats.

    Science.gov (United States)

    Beck, W; Gobatto, C

    2016-03-01

    Nocturnal rodents should be assessed at an appropriate time of day, which leads to a challenge in identifying an adequate environmental light which allows animal visualisation without perturbing physiological homeostasis. Thus, we analysed the influence of high wavelength and low intensity light during dark period on physical exercise and biochemical and haematological parameters of nocturnal rats. We submitted 80 animals to an exhaustive exercise at individualised intensity under two different illuminations during dark period. Red light (> 600 nm; experiments.

  7. Dynamic compartment specific changes in glutathione and ascorbate levels in Arabidopsis plants exposed to different light intensities

    Science.gov (United States)

    2013-01-01

    Background Excess light conditions induce the generation of reactive oxygen species (ROS) directly in the chloroplasts but also cause an accumulation and production of ROS in peroxisomes, cytosol and vacuoles. Antioxidants such as ascorbate and glutathione occur in all cell compartments where they detoxify ROS. In this study compartment specific changes in antioxidant levels and related enzymes were monitored among Arabidopsis wildtype plants and ascorbate and glutathione deficient mutants (vtc2-1 and pad2-1, respectively) exposed to different light intensities (50, 150 which was considered as control condition, 300, 700 and 1,500 μmol m-2 s-1) for 4 h and 14 d. Results The results revealed that wildtype plants reacted to short term exposure to excess light conditions with the accumulation of ascorbate and glutathione in chloroplasts, peroxisomes and the cytosol and an increased activity of catalase in the leaves. Long term exposure led to an accumulation of ascorbate and glutathione mainly in chloroplasts. In wildtype plants an accumulation of ascorbate and hydrogen peroxide (H2O2) could be observed in vacuoles when exposed to high light conditions. The pad2-1 mutant reacted to long term excess light exposure with an accumulation of ascorbate in peroxisomes whereas the vtc2-1 mutant reacted with an accumulation of glutathione in the chloroplasts (relative to the wildtype) and nuclei during long term high light conditions indicating an important role of these antioxidants in these cell compartments for the protection of the mutants against high light stress. Conclusion The results obtained in this study demonstrate that the accumulation of ascorbate and glutathione in chloroplasts, peroxisomes and the cytosol is an important reaction of plants to short term high light stress. The accumulation of ascorbate and H2O2 along the tonoplast and in vacuoles during these conditions indicates an important route for H2O2 detoxification under these conditions. PMID

  8. A Bloch equation approach to intensity dependent optical spectra of light harvesting complex II: excitation dependence of light harvesting complex II pump-probe spectra.

    Science.gov (United States)

    Richter, Marten; Renger, Thomas; Knorr, Andreas

    2008-01-01

    On the basis of the recent progress in the resolution of the structure of the antenna light harvesting complex II (LHC II) of the photosystem II, we propose a microscopically motivated theory to predict excitation intensity-dependent spectra. We show that optical Bloch equations provide the means to include all 2( N ) excited states of an oligomer complex of N coupled two-level systems and analyze the effects of Pauli Blocking and exciton-exciton annihilation on pump-probe spectra. We use LHC Bloch equations for 14 Coulomb coupled two-level systems, which describe the S (0) and S (1) level of every chlorophyll molecule. All parameter introduced into the Hamiltonian are based on microscopic structure and a quantum chemical model. The derived Bloch equations describe not only linear absorption but also the intensity dependence of optical spectra in a regime where the interplay of Pauli Blocking effects as well as exciton-exciton annihilation effects are important. As an example, pump-probe spectra are discussed. The observed saturation of the spectra for high intensities can be viewed as a relaxation channel blockade on short time scales due to Pauli blocking. The theoretical investigation is useful for the interpretation of the experimental data, if the experimental conditions exceed the low intensity pump limit and effects like strong Pauli Blocking and exciton-exciton annihilation need to be considered. These effects become important when multiple excitations are generated by the pump pulse in the complex.

  9. Determination of eye safety filter protection factors associated with retinal thermal hazard and blue light photochemical hazard for intense pulsed light sources

    Energy Technology Data Exchange (ETDEWEB)

    Clarkson, D McG [Department of Clinical Physics and Bioengineering, Arden Cancer Centre, Walsgrave Hospital, UHCW NHS Trust, Coventry, CV2 2DX (United Kingdom)

    2006-02-21

    An assessment is provided of protection factors afforded for retinal thermal hazard and blue light photochemical hazard for a range of filters used with intense pulsed light sources (IPLs). A characteristic IPL spectrum based on black body radiation at 5000 K with a low cut filter at 515 nm was identified as suitable for such estimations. Specific filters assessed included types with idealized transmission properties and also a range of types whose transmission characteristics were measured by means of a Bentham DMc150 spectroradiometer. Predicted behaviour based on these spectra is outlined which describes both the effectiveness of protection and the level of luminous transmittance afforded. The analysis showed it was possible to describe a figure of merit for a particular filter material relating the degree of protection provided and corresponding value of luminous transmittance. This consideration is important for providing users of IPL equipment with safety eyewear with adequate level of visual transmittance. (note)

  10. Measuring anisotropy ellipse of atmospheric turbulence by intensity correlations of laser light.

    Science.gov (United States)

    Wang, Fei; Toselli, Italo; Li, Jia; Korotkova, Olga

    2017-03-15

    An experimental study has been performed of a laser beam propagating horizontally through the near-ground atmosphere above a grassy field at the University of Miami (UM) Coral Gables campus. The average intensity, scintillation index, and intensity correlation function are measured in the receiver plane for three channels with different turbulent conditions and at three different heights above the ground. Our results reveal that along short links (210 m) only the intensity correlation function captures the anisotropic information of turbulence, corresponding to the refractive index anisotropy ellipse of atmospheric fluctuations. In addition, we report an interesting phenomenon relating to turbulence eddy orientation near the ground. We confirmed that the experimental results are in agreement with the numerical simulations based on the multiple phase-screen method. Our findings provide an efficient method of determining the anisotropic parameters of atmospheric turbulence.

  11. Measurement of Concentration Distribution of Hydrogen Gas Flow by Measuring the Intensity of Raman Scattering Light

    Science.gov (United States)

    Asahi, Ippei; Ninomiya, Hideki

    An experimental study to visualize and measure the concentration distribution of hydrogen gas flow using the Raman scattering was performed. A Nd:YAG laser of wavelength at 355 nm was used, and the beam pattern was transformed into a rectangle and a sheet beam was formed. The Raman scattered light was observed at a right angle with respect to the laser beam axis using a gated ICCD camera and an interference filter. Shadowgraph images were obtained at the same condition. The Raman scattering light image from atmospheric nitrogen was first acquired and the function of Raman scattering light acquisition and the background light suppression was confirmed. Next, images of the Raman scattering light image and shadowgraph of hydrogen gas discharged from a nozzle into the atmosphere were acquired. The two obtained Raman images were compared and the spatial concentration distribution of the flow of the hydrogen gas at different flow rates was calculated. This method is effective for visualizing the gas flow and measuring the concentration distribution of the Raman active molecules, such as hydrogen gas.

  12. Timing and intensity of light correlate with body weight in adults.

    Directory of Open Access Journals (Sweden)

    Kathryn J Reid

    Full Text Available Light exposure can influence sleep and circadian timing, both of which have been shown to influence weight regulation. The goal of this study was to evaluate the relationship between ambient light, sleep and body mass index. Participants included 54 individuals (26 males, mean age 30.6, SD = 11.7 years. Light levels, sleep midpoint and duration were measured with wrist actigraphy (Actiwatch-L for 7 days. BMI was derived from self-reported height and weight. Caloric intake was determined from 7 days of food logs. For each participant, light and activity data were output in 2 minute epochs, smoothed using a 5 point (10 minute moving average and then aggregated over 24 hours. The mean light timing above 500 lux (MLiT500 was defined as the average clock time of all aggregated data points above 500 lux. MLiT500 was positively correlated with BMI (r = 0.51, p<0.001, and midpoint of sleep (r = 0.47, p<0.01. In a multivariable linear regression model including MLiT500 and midpoint of sleep, MLiT500 was a significant predictor of BMI (B = 1.26 SE = 0.34, β = 0.53 p = 0.001, r2Δ = 0.22. Adjusting for covariates, MLiT500 remained an independent predictor of BMI (B = 1.28 SE = 0.36, β = 0.54, p = 0.002, r2Δ = 0.20. The full model accounted for 34.7% of the variance in BMI (p = 0.01. Exposure to moderate levels of light at biologically appropriate times can influence weight, independent of sleep timing and duration.

  13. Ponderomotive dressing of doubly-excited states with intensity-controlled laser light

    Directory of Open Access Journals (Sweden)

    Ding Thomas

    2013-03-01

    Full Text Available We laser-dress several doubly-excited states in helium. Tuning the coupling-laser intensity from perturbative to the strong-coupling regime, we are able to measure phases imprinted on the two-electron wavefunctions, and observe a new continuum coupling mechanism.

  14. Describing the light intensity dependence of polymer : fullerene solar cells using an adapted Shockley diode model

    NARCIS (Netherlands)

    Slooff, L. H.; Veenstra, S. C.; Kroon, J. M.; Verhees, W.; Koster, L. J. A.; Galagan, Y.

    2014-01-01

    Solar cells are generally optimised for operation under AM1.5 100 mW cm(-2) conditions. This is also typically done for polymer solar cells. However, one of the entry markets for this emerging technology is portable electronics. For this market, the spectral shape and intensity of typical illuminati

  15. Reduced irradiation time in slow-curing of resin composite using an intensity-changeable light source.

    Science.gov (United States)

    Abo, Tomoko; Uno, Shigeru; Tagami, Junji

    2005-06-01

    Possibility to shorten the total irradiation time in slow-curing with an intensity-changeable light source, Curetron 7 (CT-7), was investigated for four hybrid-type resin composites. Irradiation condition with CT-7 was assigned as 10 or 20 seconds at low light intensity (230 mW/cm2) and followed by 20 or 10 seconds at high intensity (600 mW/cm2) respectively (i.e., a total of 30 seconds). For a reference, irradiation was carried out for 30 seconds using a halogen lamp (900 mW/cm2). After irradiation, mechanical properties of the cured composites--in terms of microhardness and flexural strength--were evaluated. Also, cavity adaptation was examined in standardized, cylindrical dentin cavities treated with an adhesive system. Compared to the reference irradiation, slow-curing with CT-7 produced acceptable mechanical properties and better adaptation. These results suggested that total exposure time of slow-curing with CT-7 could be shortened to 30 seconds.

  16. Myogenic response of human skeletal muscle to 12 weeks of resistance training at light loading intensity

    DEFF Research Database (Denmark)

    Mackey, Abigail; Holm, L; Reitelseder, S

    2011-01-01

    There is strong evidence for enhanced numbers of satellite cells with heavy resistance training. The satellite cell response to very light muscle loading is, however, unknown. We, therefore, designed a 12-week training protocol where volunteers trained one leg with a high load (H) and the other leg....... A significant main effect of time was observed (Pinduce an increase in the number of satellite...

  17. A Tale of Two Emergences: Sunrise II Observations of Emergence Sites in a Solar Active Region

    CERN Document Server

    Centeno, Rebecca; Iniesta, Jose Carlos Del Toro; Solanki, Sami K; Barthol, Peter; Gandorfer, Achim; Gizon, Laurent; Hirzberger, Johann; Riethmuller, Tino L; van Noort, Michiel; Suarez, David Orozco; Schmidt, Wolfgang; Pillet, Valentin Martinez; Knolker, Michael

    2016-01-01

    In June 2013, the two scientific instruments onboard the second Sunrise mission witnessed, in detail, a small-scale magnetic flux emergence event as part of the birth of an active region. The Imaging Magnetograph Experiment (IMaX) recorded two small (~5 arcsec) emerging flux patches in the polarized filtergrams of a photospheric Fe I spectral line. Meanwhile, the Sunrise Filter Imager (SuFI) captured the highly dynamic chromospheric response to the magnetic fields pushing their way through the lower solar atmosphere. The serendipitous capture of this event offers a closer look at the inner workings of active region emergence sites. In particular, it reveals in meticulous detail how the rising magnetic fields interact with the granulation as they push through the Sun's surface, dragging photospheric plasma in their upward travel. The plasma that is burdening the rising field slides along the field lines, creating fast downflowing channels at the footpoints. The weight of this material anchors this field to the...

  18. The Effect of the Cool Intense Pulsed Light (CIPL on Hair Removal of Chin Area in Hirsute Women

    Directory of Open Access Journals (Sweden)

    SH Njafei Dolatabadi

    2012-12-01

    Full Text Available Abstract Background & aim: Hirsutism can esthetically cause significant psychosocial consequences in hirsute women. Different methods, so far, have been applied for hair removal, and the Cool Intense Pulsed Light (CIPL system is one of them. The aim of this study was to determine the effect and side effects of the CIPL method on removing the hairs of the chin area in hirsute women. Methods: This is a interventional study in which 30 women suffering from hirsutism referred to a dermatologist's clinic in Yasuj, Iran were participated during 2009-2010. A convenience sampling method was used for data collection. Subjects underwent the Cool Intense Pulsed Light method over 6 months, one session per month . To compare the effect of the applied intervention, number of hair on the chin area were compared before and after the intervention Collected data were analyzed by the SPSS software using descriptive and analytic statistics such as t-test, paired t-test and ANOVA, considering α=0.05. Results: The duration of affliction with hirsutism was 1-15 year. The mean number of hairs of the chin area before and after the intervention were 288.2± 229.2 and 56.4± 43.8 respectively. Paired T-test analysis revealed that the difference is significant (p=0.001. None of the participants reported any specific problems related to the applied intervention. Conclusion: treatment efficacy of CIPL for hirsutism was 80 percent. However, we suggest further studies to confirm these findings. Key words: Cool Intense Pulsed Light, Hirsutism, Hair removal

  19. Efficacy and safety of intense pulsed light in the treatment of mild-to-moderate acne vulgaris

    Directory of Open Access Journals (Sweden)

    Waheed Zaman Khan

    2017-04-01

    Full Text Available Acne vulgaris is a very common chronic inflammatory disease of pilosebaceous units. It can be associated with considerable loss of self-esteem and psychological morbidity when left untreated. With the emergence of lasers and intense pulsed light, long-term reduction of acne lesions is now possible. The success of these optical devices depends on the selected parameters and biologic variables of patient. The objective of this study is to determine the efficacy and safety of intense pulsed light (IPL in the treatment of mild-to-moderate acne vulgaris. This interventional study was conducted for a period of one year after approval of synopsis. A total of 75 patients of mild-to-moderate acne vulgaris were included through non-probability, convenience sampling. Patients were subjected to intense pulsed light (IPL therapy once a week for four weeks. Digital photography was done at the baseline and at the sixth week. Follow-up was done after two weeks of completion of four sessions. Repeated measurement ANOVA was used for significance of IPL at six weeks of follow-up. The p value 50% reduction with therapy. Percentage reduction was observed as 49 ± 20% at final follow-up. Papules count was reduced from 11.95 ± 2.89 to 6.69 ± 2.96, pustules count was reduced from 2.55 ± 1.54 to 0.79 ± 1.02 from baseline to final follow-up visit. 16 subjects showed mild erythema that resolved within 24 h. None of the patients showed any severe side effects at final follow-up visit. We conclude from the results of this study that IPL is safe and efficacious in more than half of the patients in the treatment of mild and moderate acne vulgaris. A long-term follow-up is required to determine long-term safety on skin following such procedures.

  20. Effects of water stress and light intensity on chlorophyll fluorescence parameters and pigments of Aloe vera L.

    Science.gov (United States)

    Hazrati, Saeid; Tahmasebi-Sarvestani, Zeinolabedin; Modarres-Sanavy, Seyed Ali Mohammad; Mokhtassi-Bidgoli, Ali; Nicola, Silvana

    2016-09-01

    Aloe vera L. is one of the most important medicinal plants in the world. In order to determine the effects of light intensity and water deficit stress on chlorophyll (Chl) fluorescence and pigments of A. vera, a split-plot in time experiment was laid out in a randomized complete block design with four replications in a research greenhouse. The factorial combination of three light intensities (50, 75 and 100% of sunlight) and four irrigation regimes (irrigation after depleting 20, 40, 60 and 80% of soil water content) were considered as main factors. Sampling time was considered as sub factor. The first, second and third samplings were performed 90, 180 and 270 days after imposing the treatments, respectively. The results demonstrated that the highest light intensity and the severe water stress decreased maximum fluorescence (Fm), variable fluorescence (Fv)/Fm, quantum yield of PSII photochemistry (ФPSII), Chl and photochemical quenching (qP) but increased non-photochemical quenching (NPQ), minimum fluorescence (F0) and Anthocyanin (Anth). Additionally, the highest Fm, Fv/Fm, ФPSII and qP and the lowest NPQ and F0 were observed when 50% of sunlight was blocked and irrigation was done after 40% soil water depletion. Irradiance of full sunlight and water deficit stress let to the photoinhibition of photosynthesis, as indicated by a reduced quantum yield of PSII, ФPSII, and qP, as well as higher NPQ. Thus, chlorophyll florescence measurements provide valuable physiological data. Close to half of total solar radiation and irrigation after depleting 40% of soil water content were selected as the most efficient treatments.

  1. EFFECT OF Cu AND Mn TOXICITY ON CHLOROPHYLL FLUORESCENCE AND GAS EXCHANGE IN RICE AND SUNFLOWER UNDER DIFFERENT LIGHT INTENSITIES

    Directory of Open Access Journals (Sweden)

    Hajiboland R.

    2007-06-01

    Full Text Available Copper (Cu and manganese (Mn are essential micronutrients for plants, but toxic at high concentrations. Responses of rice (Oryza sativa L. and sunflower (Helianthus annuus L. to toxic concentrations of Mn and Cu (up to 100 μM were studied under three light intensities including low (LL, PPFD=100, intermediate (IL, PPFD=500 and high (HL, PPFD=800 light intensities in hydroponic medium. Rice plants showed higher susceptibility than sunflower to both heavy metals concerning dry matter of shoot and root. Growing under higher light intensity strengthened the effect of Cu toxicity while ameliorated that of Mn, the latter was attributed to the lower Mn accumulation of HL plants in both shoot and root. Chlorophyll content of leaves was influenced negatively only by Cu treatment and that at the highest concentration in the medium (100 μM. Similar with growth results, reduction of net assimilation rate (A was higher in HL than LL plants treated by excess Cu, but in contrast to growth response, reduction was more prominent in sunflower than rice. Excess Mn-induced reduction of A was similar between LL and HL plants and was greater in sunflower than rice. Reduction of A was partly attributable to stomatal limitation, but non-stomatal mechanisms were also involved in this reduction. Copper and Mn treatment did not change the optimal quantum efficiency of PSII in dark-adapted chloroplasts (Fv/Fm ratio, but Fv/F0 was influenced particularly by Cu treatment, the reduction was higher in rice than sunflower and in HL compared to LL plants. Regarding excess Cu and Mn-mediated alterations in chlorophyll concentration, Fv/F0 and Tm values, it was suggested that, Cu and Mn toxicity depress the leaf photosynthetic capacity primarily by causing a significant alteration of the composition and functional competence of the photosynthetic units rather a reduction in the number of photosynthetic units (PSUs per unit leaf area.

  2. Relationship between caffeine content and flavor with light intensity of several coffee Robusta clones

    OpenAIRE

    Novie Pranata Erdiansyah; Yusianto Yusianto

    2012-01-01

    Coffee is a refreshing beverage product and its price is determined by physical quality and flavor. An excellent coffee flavor is resulted only from qualified coffee beans, produced by well managed plantation. The objective of this experiment was to study the effect of sunlight intensity entering coffee farm on flavor profiles and caffeine content of Robusta coffee. The experiment was conducted at the field experimental Kaliwining Estate of Indonesian Coffee and Cocoa Research Institute (ICCR...

  3. Report from the NSLS workshop: Sources and applications of high intensity uv-vuv light

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, E.D.; Hastings, J.B. [eds.

    1990-12-31

    A workshop was held to evaluate sources and applications of high intensity, ultra violet (UV) radiation for biological, chemical, and materials sciences. The proposed sources are a UV free electron laser (FEL) driven by a high brightness linac and undulators in long, straight sections of a specially designed low energy (400 MeV) storage ring. These two distinct types of sources will provide a broad range of scientific opportunities that were discussed in detail during the workshop.

  4. Report from the NSLS workshop: Sources and applications of high intensity uv-vuv light

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, E.D.; Hastings, J.B. (eds.)

    1990-01-01

    A workshop was held to evaluate sources and applications of high intensity, ultra violet (UV) radiation for biological, chemical, and materials sciences. The proposed sources are a UV free electron laser (FEL) driven by a high brightness linac and undulators in long, straight sections of a specially designed low energy (400 MeV) storage ring. These two distinct types of sources will provide a broad range of scientific opportunities that were discussed in detail during the workshop.

  5. Interplay between radiation pressure force and scattered light intensity in the cooperative scattering by cold atoms

    CERN Document Server

    Bienaime, Tom; Chabe, Julien; Rouabah, Mohamed-Taha; Bellando, Louis; Courteille, Philippe W; Piovella, Nicola; Kaiser, Robin

    2013-01-01

    The interplay between the superradiant emission of a cloud of cold two-level atoms and the radiation pressure force is discussed. Using a microscopic model of coupled atomic dipoles driven by an external laser, the radiation field and the average radiation pressure force are derived. A relation between the far-field scattered intensity and the force is derived, using the optical theorem. Finally, the scaling of the sample scattering cross section with the parameters of the system is studied.

  6. 3D PIC simulations of electron beams created via reflection of intense laser light from a water target

    CERN Document Server

    Ngirmang, Gregory K; Feister, Scott; Morrison, John T; Chowdhury, Enam A; Frische, Kyle; Roquemore, W M

    2015-01-01

    We present 3D Particle-in-Cell (PIC) modeling of an ultra-intense laser experiment by the Extreme Light group at the Air Force Research Laboratory (AFRL) using the PIC code LSP. This is the first time PIC simulations have been performed in 3D for this experiment which involves an ultra-intense, short-pulse (30 fs) laser interacting with a water jet target at normal incidence. These 3D PIC simulation results are compared to results from 2D(3$v$) PIC simulations for both $5.4\\cdot10^{17}$ W cm$^{-2}$ and $3\\cdot10^{18}$ W cm$^{-2}$ intensities. Comparing the 2D(3$v$) and 3D simulation results, the laser-energy-to-ejected-electron-energy conversion efficiencies were comparable, but the angular distribution of ejected electrons show interesting differences with qualitative differences at higher intensity. An analytic plane-wave model is provided that provides some explanation for the angular distribution and energies of ejected electrons in the 2D(3$v$) simulations. We also performed a 3D simulation with circular...

  7. Sunrise and Sunset Azimuths in the Planning of Ancient Chinese Towns

    OpenAIRE

    Sparavigna, Amelia Carolina

    2013-01-01

    Abstract: In the planning of some Chinese towns we can see an evident orientation with the cardinal direction north-south. However, other features reveal a possible orientation with the directions of sunrise and sunset on solstices too, as in the case of Shangdu (Xanadu), the summer capital of Kublai Khan. Here we discuss some other examples of a possible solar orientation in the planning of ancient towns. We will analyse the plans of Xi'an, Khanbalik and Dali

  8. A possible role of sunrise/sunset azimuth in the planning of ancient Chinese towns

    CERN Document Server

    Sparavigna, Amelia Carolina

    2013-01-01

    In the planning of some Chinese towns we can see an evident orientation with the cardinal north-south direction. However, other features reveal a possible orientation with the sunrise/sunset azimuth on solstices too, as in the case of Shangdu (Xanadu), the summer capital of Kublai Khan. Here we discuss some other examples of a possible solar orientation in the planning of ancient towns. We will analyze the plans of Xi'an, Khanbalik and Dali.

  9. Organic dyes with intense light absorption especially suitable for application in thin-layer dye-sensitized solar cells.

    Science.gov (United States)

    Dessì, Alessio; Calamante, Massimo; Mordini, Alessandro; Peruzzini, Maurizio; Sinicropi, Adalgisa; Basosi, Riccardo; Fabrizi de Biani, Fabrizia; Taddei, Maurizio; Colonna, Daniele; Di Carlo, Aldo; Reginato, Gianna; Zani, Lorenzo

    2014-11-21

    Three new thiazolo[5,4-d]thiazole-based organic dyes have been designed and synthesized for employment as DSSC sensitizers. Alternation of the electron poor thiazolothiazole unit with two propylenedioxythiophene (ProDOT) groups ensured very intense light absorption in the visible region (ε up to 9.41 × 10(4) M(-1) cm(-1) in THF solution). The dyes were particularly suitable for application in transparent and opaque thin-layer DSSCs (TiO2 thickness: 5.5-6.5 μm, efficiencies up to 7.71%), thus being good candidates for production of solar cells under simple fabrication conditions.

  10. Prediction of the Bandgap of a Core-Shell Microsphere via Light Intensity Fluctuations

    Directory of Open Access Journals (Sweden)

    Moon Kyu Choi

    2011-01-01

    Full Text Available It has been experimentally observed that in the case of microspheres irradiated by light, the absorption wavelength shift occurs, known as the blueshift, with changing shell materials (i.e., by decreasing the refractive index of the shell. In the present investigation, we want to demonstrate it numerically by using the boundary element method. The material used for the simulation is a core-shell (SiO2 and another material of a larger refractive index microsphere and it is irradiated by unpolarized monochromatic light wave. This paper intends to demonstrate that it is possible to predict the bandgap of a core-shell microsphere resulting from two different bandgap materials and that the numerical simulation employed produces the blueshift.

  11. Optical coherence tomography imaging of telangiectasias during intense pulsed light treatment

    DEFF Research Database (Denmark)

    Ring, Hans Christian; Mogensen, Mette; Banzhaf, Christina

    2013-01-01

    Vascular malformations commonly occur in the facial region, and can be associated with significant stigma and embarrassment. Studies have shown that even recommended light-based treatments do not always result in complete clearance. This indicates the need for more accurate pre-treatment assessment...... and minutes after IPL treatment. OCT images of the telangiectasias before treatment were displayed as hyporeflective/signal poor bands clearly demarcated from the surrounding tissue. Minutes after treatment, OCT images demonstrated two different reactions. (1) Narrow hyperreflective bands surrounding...... the vessels, which may indicate edema or insufficient coagulation. (2) Hyperreflective signals within the lumen of the vessels, compatible with the expected irreversible microthrombus formation in the vessels. OCT imaging is capable of real-time assessment of tissue damage during light and laser treatment...

  12. Laser Heating of Solid Matter by Light-Pressure-Driven Shocks at Ultrarelativistic Intensities

    Energy Technology Data Exchange (ETDEWEB)

    Akli, K.U.; Hansen, S.B.; Kemp, A.J.; Freeman, R.R.; Beg, F.N.; Clark, D.C.; Chen, S.D.; Hey, D.; Hatchett, S.P.; Highbarger, K.; Giraldez, E.; Green, J.S.; Gregori, G.; Lancaster, K.L.; Ma, T.; MacKinnon, A.J.; Norreys, P.; Patel, N.; Pasley, J.; Shearer, C.; Stephens, R.B.; Stoeckl, C.; Storm, M.; Theobald, W.; Van Woerkom, L.D.; Weber, R.; Key, M.H.

    2008-04-29

    The heating of solid targets irradiated by 5 x 10^20 W cm^-2, 0.8 ps, 1.05 um wavelength laser light is studied by x-ray spectroscopy of the K-shell emission from thin layers of Ni, Mo, and V. A surface layer is heated to ~5 keV with an axial temperature gradient of 0.6 um scale length. Images of Ni Ly sub-alpha show the hot region has <25 um diameter. These data are consistent with collisional particle-in-cell simulations using preformed plasma density profiles from hydrodynamic modeling which show that the >100 Gbar light pressure compresses the preformed plasma and dries a shock into the solid, heating a thin layer.

  13. Effects of nutrients and light intensity on the growth and biochemical composition of a marine microalga Odontella aurita

    Science.gov (United States)

    Xia, Song; Wan, Linglin; Li, Aifen; Sang, Min; Zhang, Chengwu

    2013-11-01

    Algal biotechnology has advanced greatly in the past three decades. Many microalgae are now cultivated to produce bioactive substances. Odontella aurita is a marine diatom industrially cultured in outdoor open ponds and used for human nutrition. For the first time, we have systematically investigated the effects of culture conditions in cylindrical glass columns and flat-plate photobioreactors, including nutrients (nitrogen, phosphorus, silicon, and sulfur), light intensity and light path, on O. aurita cell growth and biochemical composition (protein, carbohydrate, β-1,3-glucan, lipids, and ash). The optimal medium for photoautotrophic cultivation of O. aurita contained 17.65 mmol/L nitrogen, 1.09 mmol/L phosphorus, 0.42 mmol/L silicon, and 24.51 mmol/L sulfur, yielding a maximum biomass production of 6.1-6.8 g/L and 6.7-7.8 g/L under low and high light, respectively. Scale-up experiments were conducted with flat-plate photobioreactors using different light-paths, indicating that a short light path was more suitable for biomass production of O. aurita. Analyses of biochemical composition showed that protein content decreased while carbohydrate (mainly composed of β-1,3-glucan) increased remarkably to about 50% of dry weight during the entire culture period. The highest lipid content (19.7% of dry weight) was obtained under 0.11 mmol/L silicon and high light conditions at harvest time. Fatty acid Profiles revealed that 80% were C14, C16, and C20, while arachidonic acid and eicosapentaenoic acid (EPA) accounted for 1.6%-5.6% and 9%-20% of total fatty acids, respectively. High biomass production and characteristic biochemical composition Profiles make O. aurita a promising microalga for the production of bioactive components, such as EPA and β-1,3-glucan.

  14. The Intensity of the Light Diffraction by Supersonic Longitudinal Waves in Solid

    Directory of Open Access Journals (Sweden)

    Minasyan V.

    2010-04-01

    Full Text Available First, we predict existence of transverse electromagnetic field created by supersonic longitudinal waves in solid. This electromagnetic wave with frequency of ultrasonic field is moved by velocity of supersonic field toward of direction propagation of one. The average Poynting vector of superposition field is calculated by presence of the transverse electromagnetic and the optical fields which in turn provides appearance the diffraction of light.

  15. Myogenic response of human skeletal muscle to 12 weeks of resistance training at light loading intensity.

    Science.gov (United States)

    Mackey, A L; Holm, L; Reitelseder, S; Pedersen, T G; Doessing, S; Kadi, F; Kjaer, M

    2011-12-01

    There is strong evidence for enhanced numbers of satellite cells with heavy resistance training. The satellite cell response to very light muscle loading is, however, unknown. We, therefore, designed a 12-week training protocol where volunteers trained one leg with a high load (H) and the other leg with a light load (L). Twelve young healthy men [mean age 25 ± 3 standard deviation (SD) years] volunteered for the study. Muscle biopsies were collected from the m. vastus lateralis of both legs before and after the training period and satellite cells were visualized by CD56 immunohistochemistry. A significant main effect of time was observed (Pfiber (L: from 0.11 ± 0.02 to 0.13 ± 0.03; H: from 0.12 ± 0.03 to 0.15 ± 0.05, mean ± SD). The finding that 12 weeks of training skeletal muscle even with very light loads can induce an increase in the number of satellite cells reveals a new aspect of myogenic precursor cell activation and suggests that satellite cells may play a role in skeletal muscle adaptation over a broad physiological range.

  16. Light Intensity Affects Chlorophyll Synthesis During Greening Process by Metabolite Signal from Mitochondrial Alternative Oxidase in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Dawei; YUAN; Shu; 徐飞; ZHU; Feng; YUAN; Ming; YE; Huaxun; GUO; Hongqing; LV; Xin; YIN; Yanhai; 林宏辉

    2015-01-01

    Although mitochondrial alternative oxidase(AOX)has been proposed to play essential roles in high light stress tolerance,the effects of AOX on chlorophyll synthesis are unclear.Previous studies indicated that during greening,chlorophyll accumulation was largely delayed in plants whose mitochondrial cyanide-resistant respiration was inhibited by knocking out nuclear encoded AOX gene.Here we show that this delay of chlorophyll accumulation was more significant under high light condition.Inhibition of cyanide-resistant respiration was also accompanied by the increase of plastid NADPH/NADP~+ratio,especially under high light treatment which subsequently blocked the import of multiple plastidial proteins,such as some components of the photosynthetic electron transport chain,the Calvin-Benson cycle enzymes and malate/oxaloacetate shuttle components.Over expression of AOXla rescued the aoxla mutant phenotype,including the chlorophyll accumulation during greening and plastidial protein import.It thus suggests that light intensity affects chlorophyll synthesis during greening process by a metabolic signal,the AOX-derived plastidial NADPH/NADP~+ratio change.And our results thus revealed a molecular mechanism of chloroplast-mitochondria interactions.

  17. Starch and lipid accumulation in eight strains of six Chlorella species under comparatively high light intensity and aeration culture conditions.

    Science.gov (United States)

    Takeshita, Tsuyoshi; Ota, Shuhei; Yamazaki, Tomokazu; Hirata, Aiko; Zachleder, Vilém; Kawano, Shigeyuki

    2014-04-01

    The microalgae family Chlorella species are known to accumulate starch and lipids. Although nitrogen or phosphorous deficiencies promote starch and lipids formation in many microalgae, these deficiencies also limit their growth and productivity. Therefore, the Chlorellaceae strains were attempted to increase starch and lipids productivity under high-light-intensity conditions (600-μmol photons m(-2)s(-1)). The 12:12-h light-dark (LD) cycle conditions elicited more stable growth than the continuous light (LL) conditions, whereas the starch and lipids yields increased in LL conditions. The amount of starch and lipids per cell increased in Chlorella viscosa and Chlorella vulgaris in sulfur-deficient medium, and long-chain fatty acids with 20 or more carbon atoms accumulated in cells grown in sulfur-deficient medium. Accumulation of starch and lipids was investigated in eight strains. The accumulation was strain-dependent, and varied according to the medium and light conditions. Five of the eight Chlorella strains exhibited similar accumulation patterns.

  18. A portable smart phone-based plasmonic nanosensor readout platform that measures transmitted light intensities of nanosubstrates using an ambient light sensor.

    Science.gov (United States)

    Fu, Qiangqiang; Wu, Ze; Xu, Fangxiang; Li, Xiuqing; Yao, Cuize; Xu, Meng; Sheng, Liangrong; Yu, Shiting; Tang, Yong

    2016-05-21

    Plasmonic nanosensors may be used as tools for diagnostic testing in the field of medicine. However, quantification of plasmonic nanosensors often requires complex and bulky readout instruments. Here, we report the development of a portable smart phone-based plasmonic nanosensor readout platform (PNRP) for accurate quantification of plasmonic nanosensors. This device operates by transmitting excitation light from a LED through a nanosubstrate and measuring the intensity of the transmitted light using the ambient light sensor of a smart phone. The device is a cylinder with a diameter of 14 mm, a length of 38 mm, and a gross weight of 3.5 g. We demonstrated the utility of this smart phone-based PNRP by measuring two well-established plasmonic nanosensors with this system. In the first experiment, the device measured the morphology changes of triangular silver nanoprisms (AgNPRs) in an immunoassay for the detection of carcinoembryonic antigen (CEA). In the second experiment, the device measured the aggregation of gold nanoparticles (AuNPs) in an aptamer-based assay for the detection of adenosine triphosphate (ATP). The results from the smart phone-based PNRP were consistent with those from commercial spectrophotometers, demonstrating that the smart phone-based PNRP enables accurate quantification of plasmonic nanosensors.

  19. Estimation of the magnetic flux emergence rate in the quiet Sun from Sunrise data

    CERN Document Server

    Smitha, H N; Solanki, S K; Riethmueller, T

    2016-01-01

    The small-scale internetwork (IN) features are thought to be the major source of fresh magnetic flux in the quiet Sun. During its first science flight in 2009, the balloon-borne observatory Sunrise captured images of the magnetic fields in the quiet Sun at a high spatial resolution. Using these data we measure the rate at which the IN features bring magnetic flux to the solar surface. In a previous paper it was found that the lowest magnetic flux in small-scale features detected using the Sunrise observations is 9 x 10^14 Mx. This is nearly an order of magnitude smaller than the smallest fluxes of features detected in observations from Hinode satellite. In this paper, we compute the flux emergence rate (FER) by accounting for such small fluxes, which was not possible before Sunrise. By tracking the features with fluxes in the range 10^15-10^18 Mx, we measure an FER of 1100 Mx cm^-2 day^-1. The smaller features with fluxes less than or equal to 10^16 Mx are found to be the dominant contributors to the solar ma...

  20. Observational Accuracy of Sunrise and Sunset Times in the Sixth Century China

    Institute of Scientific and Technical Information of China (English)

    Yong Li

    2006-01-01

    The Daye Calendar was compiled in AD 597 in the Sui Dynasty. We investigate the records of sunrise and sunset times on the 24 solar-term days in the calendar. By converting the ancient Chinese time units, Chen, Ke and Fen to hour, minute and second, and carrying out a comparison between the ancient records and values computed with modern astronomical theory, we find that the accuracy of solar measurements in the Sui period is remarkably high:for sunrise times, the average absolute deviation is 3.63 min (this value can be further reduced to 3.03 min when erroneous data are excluded), and for sunset times it is 3.48 min. We also find that the observed sunrise and sunset times are strictly symmetrically distributed with respect to both the Winter Solstice and the Summer Solstice, with their deviations showing a similar symmetrical distribution as well. We give a discussion on the date of observation, the feature of the data, and possible reasons of the deviation.

  1. Kaks kanget: Forgotten Sunrise ning Tharaphitha enne ja nüüd / Anders Melts, Ants Lill ; intervjueerinud Mart Kalvet

    Index Scriptorium Estoniae

    Melts, Anders

    2009-01-01

    Küsimustele vastavad dark-elektro-bändi Forgotten Sunrise laulja Anders Melts ja pagan-metal-bändi Tharaphita laulja-kitarrist Ants Lill. Ansamblitest ja nende esimestest heliplaatidest, mis üllitati hiljuti uuesti plaadifirma Nailboard Records poolt: Tharaphita albumi "Raev" digipack-CD, millele on lisatud 1996. aastal ilmunud neljalooline demosalvestis "Kui varjud põlevad" ja Forgotten Sunrise demo "Behind The Abysmal Sky" (1993) ja minialbumi "Forever Sleeping Greystones" (1994) lood

  2. Kaks kanget: Forgotten Sunrise ning Tharaphitha enne ja nüüd / Anders Melts, Ants Lill ; intervjueerinud Mart Kalvet

    Index Scriptorium Estoniae

    Melts, Anders

    2009-01-01

    Küsimustele vastavad dark-elektro-bändi Forgotten Sunrise laulja Anders Melts ja pagan-metal-bändi Tharaphita laulja-kitarrist Ants Lill. Ansamblitest ja nende esimestest heliplaatidest, mis üllitati hiljuti uuesti plaadifirma Nailboard Records poolt: Tharaphita albumi "Raev" digipack-CD, millele on lisatud 1996. aastal ilmunud neljalooline demosalvestis "Kui varjud põlevad" ja Forgotten Sunrise demo "Behind The Abysmal Sky" (1993) ja minialbumi "Forever Sleeping Greystones" (1994) lood

  3. SUNrises on the International Plant Nucleus Consortium: SEB Salzburg 2012.

    Science.gov (United States)

    Graumann, Katja; Bass, Hank W; Parry, Geraint

    2013-01-01

    The nuclear periphery is a dynamic, structured environment, whose precise functions are essential for global processes-from nuclear, to cellular, to organismal. Its main components-the nuclear envelope (NE) with inner and outer nuclear membranes (INM and ONM), nuclear pore complexes (NPC), associated cytoskeletal and nucleoskeletal components as well as chromatin are conserved across eukaryotes (Fig. 1). In metazoans in particular, the structure and functions of nuclear periphery components are intensely researched partly because of their involvement in various human diseases. While far less is known about these in plants, the last few years have seen a significant increase in research activity in this area. Plant biologists are not only catching up with the animal field, but recent findings are pushing our advances in this field globally. In recognition of this developing field, the Annual Society of Experimental Biology Meeting in Salzburg kindly hosted a session co-organized by Katja Graumann and David E. Evans (Oxford Brookes University) highlighting new insights into plant nuclear envelope proteins and their interactions. This session brought together leading researchers with expertise in topics such as epigenetics, meiosis, nuclear pore structure and functions, nucleoskeleton and nuclear envelope composition. An open and friendly exchange of ideas was fundamental to the success of the meeting, which resulted in founding the International Plant Nucleus Consortium. This review highlights new developments in plant nuclear envelope research presented at the conference and their importance for the wider understanding of metazoan, yeast and plant nuclear envelope functions and properties.

  4. The Imaging Magnetograph eXperiment (IMaX) for the Sunrise balloon-borne solar observatory

    CERN Document Server

    Pillet, V Martinez; Alvarez-Herrero, A; Domingo, V; Bonet, J A; Fernandez, L Gonzalez; Jimenez, A Lopez; Pastor, C; Blesa, J L Gasent; Mellado, P; Piqueras, J; Aparicio, B; Balaguer, M; Ballesteros, E; Belenguer, T; Rubio, L R Bellot; Berkefeld, T; Collados, M; Deutsch, W; Feller, A; Girela, F; Grauf, B; Heredero, R L; Herranz, M; Jeronimo, J M; Laguna, H; Meller, R; Menendez, M; Morales, R; Suarez, D Orozco; Ramos, G; Reina, M; Ramos, J L; Rodriguez, P; Sanchez, A; Uribe-Patarroyo, N; Barthol, P; Gandorfer, A; Knoelker, M; Schmidt, W; Solanki, S K; Dominguez, S Vargas

    2010-01-01

    The Imaging Magnetograph eXperiment (IMaX) is a spectropolarimeter built by four institutions in Spain that flew on board the Sunrise balloon-borne telesocope in June 2009 for almost six days over the Arctic Circle. As a polarimeter IMaX uses fast polarization modulation (based on the use of two liquid crystal retarders), real-time image accumulation, and dual beam polarimetry to reach polarization sensitivities of 0.1%. As a spectrograph, the instrument uses a LiNbO3 etalon in double pass and a narrow band pre-filter to achieve a spectral resolution of 85 mAA. IMaX uses the high Zeeman sensitive line of Fe I at 5250.2 AA and observes all four Stokes parameters at various points inside the spectral line. This allows vector magnetograms, Dopplergrams, and intensity frames to be produced that, after reconstruction, reach spatial resolutions in the 0.15-0.18 arcsec range over a 50x50 arcsec FOV. Time cadences vary between ten and 33 seconds, although the shortest one only includes longitudinal polarimetry. The s...

  5. Darwinian adaptation of proteorhodopsin to different light intensities in the marine environment

    Science.gov (United States)

    Bielawski, Joseph P.; Dunn, Katherine A.; Sabehi, Gazalah; Béjà, Oded

    2004-01-01

    Proteorhodopsin, a retinal-binding protein, represents a potentially significant source of light-driven energy production in the world's oceans. The distribution of photochemically divergent proteorhodopsins is stratified according to depth. Here, we present evidence that such photochemical diversity was tuned by Darwinian selection. By using a Bayesian method, we identified sites targeted by Darwinian selection and mapped them to three-dimensional models of proteorhodopsins. We suggest that spectral fine-tuning results from the combined effect of amino acids that directly interact with retinal and those that influence the confirmation of the retinal-binding pocket. PMID:15466697

  6. Response of vegetable organisms to quasi-monochromatic light of different duration, intensity and wavelength

    Energy Technology Data Exchange (ETDEWEB)

    Budagovsky, A V; Solovykh, N V [I.V.Michurin All-Russian Recearch Institute of Fruit Crops Genetics and Breeding (Russian Federation); Budagovskaya, O N [I.V.Michurin All-Russia Research and Development Institute of Gardening, Michurinsk, Tambov region (Russian Federation); Budagovsky, I A [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2015-04-30

    By the example of vegetable organisms differing in structure and functional properties it is shown that their response to the action of quasi-monochromatic light from laser sources does not obey the Bunsen – Roscoe dose law. The dependence of biological effect on the irradiation time has the multimodal (multiextremal) form with alternating maxima and minima of the stimulating effect. Such a property manifests itself in the spectral ranges, corresponding to photoinduced conversion of chromoproteins of photocontrol systems and is probably related to the cyclic variations of metabolic activity in vegetable cells. (biophotonics)

  7. Photosynthetic response of seagrasses to ultraviolet-a radiation and the influence of visible light intensity.

    Science.gov (United States)

    Trocine, R P; Rice, J D; Wells, G N

    1982-02-01

    Inhibition of photosynthesis by ultraviolet-A radiation (UV-A, 315-380 nanometers) was examined in three marine angiosperms: Halophila engelmannii Aschers, Halodule wrightii Aschers, and Syringodium filiforme Kütz. Sensitivity to UV-A and photosensitization to UV-A by photosynthetically active radiation (PAR, 380-700 nanometers) were characterized.Net photosynthesis by Halodule and Syringodium was unaffected by UV-A irradiation in the absence of PAR. Irradiation of Syringodium by a combined beam of UV-A and PAR resulted in photosynthetic inhibition. The depression of net photosynthesis was found to be a function of PAR intensity at a fixed level of UV-A irradiation. Inhibition of photosynthesis in Halodule by the combined beam was minimal and suggests adaptation to environmental irradiation levels.Halophila was the only species examined, subject to photosynthetic inhibition by UV-A in the absence of PAR. Irradiation with PAR intensities characteristic to Halophila in the natural system as the combined beam, appeared to negate the inhibition. Increasing the PAR component of the combined beam above environmental norms resulted in photosynthetic inhibition greater than that observed for UV-A alone.

  8. Adaptability of free-floating green tide algae in the Yellow Sea to variable temperature and light intensity.

    Science.gov (United States)

    Cui, Jianjun; Zhang, Jianheng; Huo, Yuanzi; Zhou, Lingjie; Wu, Qing; Chen, Liping; Yu, Kefeng; He, Peimin

    2015-12-30

    In this study, the influence of temperature and light intensity on the growth of seedlings and adults of four species of green tide algae (Ulvaprolifera, Ulvacompressa, Ulva flexuosa and Ulvalinza) from the Yellow Sea was evaluated. The results indicated that the specific growth rate (SGR) of seedlings was much higher than that of adults for the four species. The adaptability of U. prolifera is much wider: Adult daily SGRs were the highest among the four species at 15-20 °C with 10-600 μmol · m(-2) · s(-1) and 25-30 °C with 200-600 μmol · m(-2) · s(-1). SGRs were 1.5-3.5 times greater than the other three species at 15-25 °C with 200-600 μmol · m(-2) · s(-1). These results indicate that U. prolifera has better tolerance to high temperature and light intensity than the other three species, which may in part explain why only U. prolifera undergoes large-scale outbreaks and floats to the Qingdao coast while the other three species decline and disappear at the early stage of blooming. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Using antibrowning agents to enhance quality and safety of fresh-cut avocado treated with intense light pulses.

    Science.gov (United States)

    Ramos-Villarroel, Ana Y; Martín-Belloso, Olga; Soliva-Fortuny, Robert

    2011-01-01

    The effect of antibrowning compounds on the color and firmness of fresh-cut avocado treated with intense light pulses (ILP), as well as their impact on the survival of Listeria innocua, was investigated in this study. Dipping solutions containing 2% (w/v) L-cysteine without ascorbic acid and combined with 1% (w/v) citric acid and 1% w/v calcium lactate most effectively preserved the initial color and texture of ILP-treated fresh-cut avocado. On the other hand, ILP treatments caused a reduction of more than 3 log cycles in the populations of L. innocua inoculated on fresh-cut avocado. Log reduction levels increased when antibrowning agents were combined with ILP treatments. In conclusion, the use of quality-stabilizing agents is a good option to guarantee both the microbiological safety of fresh-cut avocado treated with ILP as well as to improve its physical and chemical quality. Intense light pulses (ILP) have received considerable attention during the last years after its approval by the U.S. Food and Drug Administration (FDA) in 1996 as a decontamination method for food or food surfaces. This article presents relevant information regarding the effect of ILP treatments combined with quality-stabilizing compounds as a feasible alternative to improve the physical and chemical quality of fresh-cut avocado as well as to guarantee its microbiological safety. © 2011 Institute of Food Technologists®

  10. Sub-high Temperature and High Light Intensity Induced Irreversible Inhibition on Photosynthesis System of Tomato Plant (Solanum lycopersicum L.)

    Science.gov (United States)

    Lu, Tao; Meng, Zhaojuan; Zhang, Guoxian; Qi, Mingfang; Sun, Zhouping; Liu, Yufeng; Li, Tianlai

    2017-01-01

    High temperature and high light intensity is a common environment posing a great risk to organisms. This study aimed to elucidate the effects of sub-high temperature and high light intensity stress (HH, 35°C, 1000 μmol⋅m-2⋅s-1) and recovery on the photosynthetic mechanism, photoinhibiton of photosystem II (PSII) and photosystem I (PSI), and reactive oxygen (ROS) metabolism of tomato seedlings. The results showed that with prolonged stress time, net photosynthetic rate (Pn), Rubisco activity, maximal photochemistry efficiency (Fv/Fm), efficient quantum yield and electron transport of PSII [Y(II) and ETR(II)] and PSI [Y(I) and ETR(I)] decreased significantly whereas yield of non-regulated and regulated energy dissipation of PSII [Y(NO) and Y(NPQ)] increased sharply. The donor side limitation of PSI [Y(ND)] increased but the acceptor side limitation of PSI [Y(NA)] decreased. Content of malondialdehyde (MDA) and hydrogen peroxide (H2O2) were increased while activity of superoxide dismutase (SOD) and peroxidase (POD) were significantly inhibited compared with control. HH exposure affected photosynthetic carbon assimilation, multiple sites in PSII and PSI, ROS accumulation and elimination of Solanum lycopersicum L.

  11. Light intensity and N/P nutrient affect the accumulation of lipid and unsaturated fatty acids by Chlorella sp.

    Science.gov (United States)

    Guo, Xiaoyi; Su, Gaomin; Li, Zheng; Chang, Jingyu; Zeng, Xianhai; Sun, Yong; Lu, Yinghua; Lin, Lu

    2015-09-01

    In this study, different light intensities (80, 160, 240 and 320 μmol/m(2) s) and various mediums including control medium (CM), N/P rich medium (NPM), N rich medium (NM), and P rich medium (PM) were applied for cultivation of Chlorella sp. It was revealed that cultivation of Chlorella sp. in CM under the light intensity of 320 μmol/m(2) s led to a lipid content up to 30% enhancement, which was higher than the results of other cases. A rather high unsaturated fatty acid (UFA) content of 7.5% and unsaturated fatty acid/total fatty acid (UFA/TFA) ratio of 0.73 were obtained under 320 μmol/m(2) s in CM, indicating that the CM-320 system was applicable for the generation of UFA. Moreover, Chlorella sp. cultivated in PM under 320 μmol/m(2) s provided higher TFA content (7.3%), which was appropriate for biofuel production.

  12. [Effects of soil moisture content and light intensity on the plant growth and leaf physiological characteristics of squash].

    Science.gov (United States)

    Du, She-ni; Bai, Gang-shuan; Liang, Yin-li

    2011-04-01

    A pot experiment with artificial shading was conducted to study the effects of soil moisture content and light intensity on the plant growth and leaf physiological characteristics of squash variety "Jingyingyihao". Under all test soil moisture conditions, 30% shading promoted the growth of "Jingyingyihao", with the highest yield at 70% - 80% soil relative moisture contents. 70% shading inhibited plant growth severely, only flowering and not bearing fruits, no economic yield produced. In all treatments, there was a similar water consumption trend, i. e., both the daily and the total water consumption decreased with increasing shading and decreasing soil moisture content. Among all treatments, 30% shading and 70% - 80% soil relative moisture contents had the highest water use efficiency (2.36 kg mm(-1) hm(-2)) and water output rate (1.57 kg mm(-1) hm(-2)). The net photosynthetic rate, transpiration rate, stomatal conductance, and chlorophyll content of squash leaves decreased with increasing shading, whereas the intercellular CO2 concentration was in adverse. The leaf protective enzyme activity and proline content decreased with increasing shading, and the leaf MAD content decreased in the order of 70% shading, natural radiation, and 30% shading. Under the three light intensities, the change characteristics of squash leaf photosynthesis, protective enzyme activity, and proline and MAD contents differed with the increase of soil relative moisture content.

  13. Studies on Changes of Phenolics in the Apple Fruit Peel in Response to Light Intensity

    Institute of Scientific and Technical Information of China (English)

    HAO Yan-yan; HUANG Wei-dong; ZHANG Wen-he

    2004-01-01

    Fruits from 9-year-old apple trees (Malus domestic Borkh. cv. Fuji) were wrappedby two-layer bag in middle of June, and bags were removed in middle of September. The bag-removed treatment was performed in following three ways: once-removing all inner and outer bags; twice-removing bag (removing inner bag 3 d after removing outer bag); dipping 5 s in 1 mM salicylic acid (SA)after once-removing all bags. Changes of phenolic compounds in fruit peel in response to light environment were studied before or after removing bag. The results showed that the bagged treatment could significantly decrease the contents of UV (ultraviolet) absorbing compounds,rutin and anthocyanins of the fruit peel, but increased chlorogenic acid level. After removal of bag, the level of SA and quercetin in the fruit peel appeared peak 1 d after bag-removed,except that quercetin was decreased in SA-treated fruits. UVabsorbing compounds, anthocyanins and rutin were kept increasing all along after the removal of bag, except that chlorogenic acid was decreased during being retained inner bag in the treatment of twice removing bag. The positive correlations existed between changes of UV absorbing compounds and changes of anthocyanins or rutin. It was suggested that light played an important role in phenolics metabolism.

  14. Toward efficient light diffraction and intensity variations by using wide bandwidth surface acoustic wave

    Science.gov (United States)

    Lee, Young Ok; Chen, Fu; Lee, Kee Keun

    2016-06-01

    We have developed acoustic-optic (AO) based display units for implementing a handheld hologram display by modulating light deflection through wide bandwidth surface acoustic wave (SAW). The developed AO device consists of a metal layer, a ZnS waveguide layer, SAW inter digital transducers (IDTs), and a screen for display. When RF power with a particular resonant frequency was applied to IDTs, SAW was radiated and interfered with confined beam propagating along ZnS waveguide layer. The AO interacted beam was deflected laterally toward a certain direction depending on Bragg diffraction condition, exited out of the waveguide layer and then directed to the viewing screen placed at a certain distance from the device to form a single pixel. The deflected angles was adjusted by modulating the center frequency of the SAW IDT (SAW grating), the RF power of SAW, and the angles between propagating light beam path along waveguide and radiating SAW. The diffraction efficiency was also characterized in terms of waveguide thickness, SAW RF input power, and aperture length. Coupling of mode (COM) modeling was fulfilled to find optimal device parameters prior to fabrication. All the parameters affecting the deflection angle and efficiency to form a pixel for a three-dimensional (3D) hologram image were characterized and then discussed.

  15. Continuous ultra-low-intensity artificial daylight is not as effective as red LED light in photodynamic therapy of multiple actinic keratoses

    DEFF Research Database (Denmark)

    Wiegell, Stine Regin; Heydenreich, Jakob; Fabricius, Susanne;

    2011-01-01

    Daylight-mediated photodynamic therapy (PDT) is a simple and tolerable treatment of nonmelanoma skin cancer. It is of interest which light intensity is sufficient to prevent accumulation of protoporphyrin IX (PpIX) and effectively treat actinic keratoses (AKs). We compared the efficacy of PDT...... with light-emitting diode (LED) to daylight-mediated PDT with very low-intensity artificial daylight ('daylight') in the treatment of multiple AKs in the face or scalp....

  16. Flash kinetics and light intensity dependence of oxygen evolution in the blue-green alga Anacystis nidulans.

    Science.gov (United States)

    Ley, A C; Babcock, G T; Sauer, K

    1975-05-15

    Patterns of oxygen evolution in flashing light for the glue-green alga Anacystis nidulans are compared with those for broken spinach chloroplasts and whole cells of the green alga Chlorella pyrenoidosa. The oscillations of oxygen yield with flash number that occur in both Anacystis and Chlorella, display a greater degree of damping than do those of isolated spinach chloroplasts. The increase in damping results from a two- to threefold increase in the fraction (alpha) of reaction centers "missed" by a flash. The increase in alpha cannot be explained by non-saturing flash intensities or by the dark reduction of the oxidized intermediates formed by the flash. Anaerobic conditions markedly increase alpha in Anacystis and Chlorella but have no effect on alpha in broken spinach chloroplasts. The results signify that the mechanism of charge separation and water oxidation involved in all three orgainsms is the same, but that the pool of secondary electron acceptors between Photosystem II and Photosystem I is more reduced in the dark, in the algal cells, than in the isolated spinach chloroplasts. Oxygen evolution in flashing light for Anacystis and Chlorella show light saturation curves for the oxygen yield of the third flash (Y3) that differ markedly from those of the steady-state flashes(YS). In experiments in which all flashes are uniformly attenuated, Y3 requires nearly twice as much light as YS to reach half-saturation. Under these conditions Y3 has a sigmoidal dependence on intensity, while that of YS is hyperbolic. These differences depend on the number of flashes attenuated. When any one of the first three flashes is attenuated, the variation of Y3 with intensity resembles that of YS. When two of the first three flashes are attenuated, Y3 is intermediate in shape between the two extremes. A quantitative interpretation of these results based on the model of Kok et al. (Kik, B., Forbush, B.and McGloin, M. (1970) Photochem. Photobiol. 14, 307-321) fits the experimental

  17. Rewriting the rules governing high intensity interactions of light with matter

    Science.gov (United States)

    Borisov, Alex B.; McCorkindale, John C.; Poopalasingam, Sankar; Longworth, James W.; Simon, Peter; Szatmári, Sándor; Rhodes, Charles K.

    2016-04-01

    The trajectory of discovery associated with the study of high-intensity nonlinear radiative interactions with matter and corresponding nonlinear modes of electromagnetic propagation through material that have been conducted over the last 50 years can be presented as a landscape in the intensity/quantum energy [I-ħω] plane. Based on an extensive series of experimental and theoretical findings, a universal zone of anomalous enhanced electromagnetic coupling, designated as the fundamental nonlinear domain, can be defined. Since the lower boundaries of this region for all atomic matter correspond to ħω ~ 103 eV and I  ≈  1016 W cm-2, it heralds a future dominated by x-ray and γ-ray studies of all phases of matter including nuclear states. The augmented strength of the interaction with materials can be generally expressed as an increase in the basic electromagnetic coupling constant in which the fine structure constant α  →  Z 2 α, where Z denotes the number of electrons participating in an ordered response to the driving field. Since radiative conditions strongly favoring the development of this enhanced electromagnetic coupling are readily produced in self-trapped plasma channels, the processes associated with the generation of nonlinear interactions with materials stand in natural alliance with the nonlinear mechanisms that induce confined propagation. An experimental example involving the Xe (4d105s25p6) supershell for which Z  ≅  18 that falls in the specified anomalous nonlinear domain is described. This yields an effective coupling constant of Z 2 α  ≅  2.4  >  1, a magnitude comparable to the strong interaction and a value rendering as useless conventional perturbative analyses founded on an expansion in powers of α. This enhancement can be quantitatively understood as a direct consequence of the dominant role played by coherently driven multiply-excited states in the dynamics of the coupling. It is also

  18. Enhancement of x-ray yields from heteronuclear cluster plasmas irradiated by intense laser light

    Energy Technology Data Exchange (ETDEWEB)

    Jha, J; Mathur, D; Krishnamurthy, M [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India)

    2005-09-28

    We report a new method to enhance the x-ray emission from nano-cluster plasmas formed upon irradiation by intense femtosecond-duration laser pulses. Our experiments demonstrate that when Ar clusters are doped with H{sub 2}O the time-integrated yield of Ar K x-ray emission is enhanced by approximately 12-fold in comparison to that obtained from pure Ar clusters under otherwise identical experimental conditions. A significant alteration in the time-dependent electron density is achieved by the presence of an H{sub 2}O dopant, and this could be the possible reason for the enhancement that is observed. (letter to the editor)

  19. Light intensity and production parameters of phytocenoses cultivated on soil-like substrate under controled environment conditions

    Science.gov (United States)

    Tikhomirov, A. A.; Ushakova, S. A.; Gribovskaya, I. A.; Tirranen, L. S.; Manukovsky, N. S.; Zolotukhin, I. G.; Karnachuk, R. A.; Gros, J.-B.; Lasseur, Ch.

    To increase the degree of closure of biological life support systems of a new generation, we used vermicomposting to involve inedible phytomass in the intra-system mass exchange. The resulting product was a soil-like substrate, which was quite suitable for growing plants (Manukovsky et al. 1996, 1997). However, the soil like substrate can be regarded as a candidate for inclusion in a system only after a comprehensive examination of its physical, chemical, and other characteristics. An important criterion is the ability of the soil-like substrate to supply the necessary mineral elements to the photosynthesizing component under the chosen cultivation conditions. Thus, the purpose of this work was to study the feasibility of enhancing the production activity of wheat and radish crops by varying the intensity of photosynthetically active radiation, without decreasing the harvest index. The increase of light intensity from 920 to 1150 μmol·m -2·s -1 decreased the intensity of apparent photosynthesis of the wheat crops and slightly increased the apparent photosynthesis of the radish crops The maximum total and grain productivity (kg/m -2) of the wheat crops was attained at the irradiance of 920 μmol·m -2·s -1. Light intensity of 1150 μmol·m -2·s -1 decreased the productivity of wheat plants and had no significant effect on the productivity of the radish crops (kg/m 2) as compared to 920 μmol·m -2·s -1. The qualitative and quantitative composition of microflora of the watering solution and substrate was determined by the condition of plants, developmental phase and light intensity. By the end of wheat growth under 1150 μmol·m -2·s -1 the numbers of bacteria of the coliform family and phytopathogenic bacteria in the watering solution and substrate were an order of magnitude larger than under other illumination conditions. The obtained data suggest that the cultivation of plants in a life support system on soil-like substrate from composts has a number of

  20. Modeling and simulation of a 3D-CMOS silicon photodetector for low-intensity light detection

    Science.gov (United States)

    Sabri Alirezaei, Iman; Burte, Edmund P.

    2016-03-01

    This paper presents a design and simulation of a novel high performance 3D-silicon photodetector for implementing in the low intensity light detection at room temperature (300K). The photodetector is modeled by inspiration of general MEMS fabrication to make a 3D- structure in the silicon substrate using a bulk micromachining process, and based on a complementary metal-oxide semiconductor (CMOS) technology. The design includes a vertical n+/p junction as an optical window for lateral illumination. The simulation is carried out using COMSOL Multiphysics relying on theoretical and physical concepts, and then, the assessment of the results is done by the numerical analysis with SILVACO (Atlas) device simulator. Light is regarded as a monochromatic beam with a wavelength of 633nm that is placed 1μm far from the optical window. The simulation is considered under the reverse bias dc voltage in the steadystate. We present photocurrent-voltage (Iph-V) characteristics under different light intensities (2… 10[mW/cm2]), and dark current-voltage (Id-V) characteristics. Comparative studies of sensitivity dependence on the dopant concentration in the substrate as an intrinsic region are accomplished utilizing two different p-type silicon substrates with 1×1015 [1/cm3] and 4×1012 [1/cm3] doping concentration. Moreover, the sensitivity is evaluated with respect to the active substrate thickness. The simulated results confirmed that the high optical sensitivity of the photodetector with low dark current can be realized in this model.

  1. An Identifiable State Model To Describe Light Intensity Influence on Microalgae Growth.

    Science.gov (United States)

    Bernardi, A; Perin, G; Sforza, E; Galvanin, F; Morosinotto, T; Bezzo, F

    2014-04-23

    Despite the high potential as feedstock for the production of fuels and chemicals, the industrial cultivation of microalgae still exhibits many issues. Yield in microalgae cultivation systems is limited by the solar energy that can be harvested. The availability of reliable models representing key phenomena affecting algae growth may help designing and optimizing effective production systems at an industrial level. In this work the complex influence of different light regimes on seawater alga Nannochloropsis salina growth is represented by first principles models. Experimental data such as in vivo fluorescence measurements are employed to develop the model. The proposed model allows description of all growth curves and fluorescence data in a reliable way. The model structure is assessed and modified in order to guarantee the model identifiability and the estimation of its parametric set in a robust and reliable way.

  2. Thermal analysis of high intensity organic light-emitting diodes based on a transmission matrix approach

    Science.gov (United States)

    Qi, Xiangfei; Forrest, Stephen R.

    2011-12-01

    We use a general transmission matrix formalism to determine the thermal response of organic light-emitting diodes (OLEDs) under high currents normally encountered in ultra-bright illumination conditions. This approach, based on Laplace transforms, facilitates the calculation of transient coupled heat transfer in a multi-layer composite characteristic of OLEDs. Model calculations are compared with experimental data on 5 cm × 5 cm green and red-emitting electrophosphorescent OLEDs under various current drive conditions. This model can be extended to study other complex optoelectronic structures under a wide variety of conditions that include heat removal via conduction, radiation, and convection. We apply the model to understand the effects of using high-thermal- conductivity substrates, and the transient thermal response under pulsed-current operation.

  3. LIPID PRODUCTION BY DUNALIELLA SALINA IN BATCH CULTURE: EFFECTS OF NITROGEN LIMITATION AND LIGHT INTENSITY

    Energy Technology Data Exchange (ETDEWEB)

    Weldy, C.S.; Huesemann, M.

    2007-01-01

    Atmospheric carbon dioxide (CO2) concentrations are increasing and may cause unknown deleterious environmental effects if left unchecked. The Intergovernmental Panel on Climate Change (IPCC) has predicted in its latest report a 2°C to 4°C increase in global temperatures even with the strictest CO2 mitigation practices. Global warming can be attributed in large part to the burning of carbon-based fossil fuels, as the concentration of atmospheric CO2 is directly related to the burning of fossil fuels. Biofuels which do not add CO2 to the atmosphere are presently generated primarily from terrestrial plants, i.e., ethanol from corn grain and biodiesel from soybean oil. The production of biofuels from terrestrial plants is severely limited by the availability of fertile land. Lipid production from microalgae and its corresponding biodiesel production have been studied since the late 1970s but large scale production has remained economically infeasible due to the large costs of sterile growing conditions required for many algal species. This study focuses on the potential of the halophilic microalgae species Dunaliella salina as a source of lipids and subsequent biodiesel production. The lipid production rates under high light and low light as well as nitrogen suffi cient and nitrogen defi cient culture conditions were compared for D. salina cultured in replicate photobioreactors. The results show (a) cellular lipid content ranging from 16 to 44% (wt), (b) a maximum culture lipid concentration of 450mg lipid/L, and (c) a maximum integrated lipid production rate of 46mg lipid/L culture*day. The high amount of lipids produced suggests that D. salina, which can be mass-cultured in non-sterile outdoor ponds, has strong potential to be an economically valuable source for renewable oil and biodiesel production.

  4. Invasive submerged freshwater macrophytes are more plastic in their response to light intensity than to the availability of free CO2 in air-equilibrated water

    DEFF Research Database (Denmark)

    Eller, Franziska; Alnoee, Anette B.; Boderskov, Teis

    2015-01-01

    compensation point, and with higher concentrations of photosynthetic pigments and quantum yield. The bicarbonate uptake capacity was generally highest at the high light intensity and high concentrations of free CO2. Plasticity indices for light intensity were consistently higher than for CO2 availability......L, c. 150 lmol m 2 s 1) or low (LowL, c. 21 lmol m2 s 1) light intensity in a 2 9 2 factorial experiment. We compared the relative growth rate (RGR), several morphological traits, the photosynthetic response to light intensity and the bicarbonate uptake capacity of the four species. For every trait...... measured, we established plasticity indices for light and CO2 availability. 3. Light intensity had a greater effect than CO2 concentration on all species. The RGR of all four species was higher at high light intensity, and photosynthetic light responses acclimated to low light with a lower light...

  5. Invasive submerged freshwater macrophytes are more plastic in their response to light intensity than to the availability of free CO2 in air-equilibrated water

    DEFF Research Database (Denmark)

    Eller, Franziska; Alnoee, Anette B.; Boderskov, Teis

    2015-01-01

    compensation point, and with higher concentrations of photosynthetic pigments and quantum yield. The bicarbonate uptake capacity was generally highest at the high light intensity and high concentrations of free CO2. Plasticity indices for light intensity were consistently higher than for CO2 availability......L, c. 150 lmol m 2 s 1) or low (LowL, c. 21 lmol m2 s 1) light intensity in a 2 9 2 factorial experiment. We compared the relative growth rate (RGR), several morphological traits, the photosynthetic response to light intensity and the bicarbonate uptake capacity of the four species. For every trait...... measured, we established plasticity indices for light and CO2 availability. 3. Light intensity had a greater effect than CO2 concentration on all species. The RGR of all four species was higher at high light intensity, and photosynthetic light responses acclimated to low light with a lower light...

  6. Effects of light sources and intensity on broilers grown to heavy weights. Part 1: growth performance, carcass characteristics, and welfare indices

    Science.gov (United States)

    This study investigated the effects of light sources and light intensity on growth performance, carcass characteristics, and welfare indices of heavy broilers (> 3.0 kg) in 4 trials with 2 replications per trial. A total of 960 1-d-old Ross × Ross 708 chicks (30 males/30 females/room) were randomly ...

  7. A microsatellite library for Carica papaya L. cv. Sunrise solo Marcadores microssatélites para Carica papaya L. cv. Sunrise solo

    Directory of Open Access Journals (Sweden)

    Silvia Correa Santos

    2003-08-01

    Full Text Available In experimental areas of the Education and Researches Ilha Solteira and Jaboticabal UNESP/Campus farms were selected and tagged 20 hermaphrodite plants and 20 feminine of cultivar Sunrise Solo, Improved Sunrise Solo cv.72/12 and Baixinho of Santa Amália.The seeds origined of the selected fruits were cropped to be analysed the self-pollination efficiency and frequency of the sex in the progenies. After that, samples of the young leaf of the matrix plants were colected for the extration of the DNA. It was built five library enriched of microsatellite sequencies, using probes (TCA10, (TC13, (GATA4, (CAC10 e (TGAG8.It was possible the development of the primers only in the library that has utilized the probe (TCA10. This probe allowed the design of 32 primer pairs. From these, 31 presented pattern of unique band in agarose Metaphor and in acrilamide. For primer S36 were observed 2 bands, but with no polymorphism to differentiation in the sexual form at papaya tree culture. However, these primers can be tested, in the futures, in the investigation of the others features in segregated populations of this specie and the related species, germoplasm analysis, cultivars identification, parent evolution and molecular markers for the assisted plant breeding programs.Em áreas experimentais das Fazendas de Ensino e Pesquisa da UNESP/Campus de Ilha Solteira e Jaboticabal foram selecionadas e marcadas 20 plantas hermafroditas e 20 femininas dos cultivares Sunrise Solo, Improved Sunrise Solo cv.72/12 e Baixinho de Santa Amália. As sementes provenientes dos frutos selecionados foram plantadas para analisar-se a eficiência da autofecundação e a freqüência dos sexos nas progênies. Posteriormente, amostras de tecido foliar jovem das plantas matrizes foram coletadas para a extração de DNA. Foram construídas cinco bibliotecas enriquecidas de seqüências microsatélites, utilizando-se as sondas (TCA10, (TC13, (GATA4, (CAC10 e (TGAG8. Foi possível o

  8. The effect of nitrogen nutrition on growth and on plant hormones content in Scots pine (Pinus silvestris L. seedlings grown under light of different intensity

    Directory of Open Access Journals (Sweden)

    Marian Michniewicz

    2014-02-01

    Full Text Available Pine seedlings were cultivated in the Ingested nutrient solution containing N as NH4Cl at concentrations of 0 and 500 ppm, under a 16-hr day, at a light intensity of 1500 and 500 lx and temperature ± 20°C. Measurements of seedlings and determination of plant hormones were performed 8 weeks after sowing. It was found that more intensive light stimulated initiation of needles and lateral roots as well as elongation of needles and roots, and increased the fresh weight and dry matter of these organs. Growth stimulation of needles was correlated with an increase in free gibberellins, cytokinins, an ABA-like inhibitor and with a decrease in auxins and water content of tissues. A similar effect of light on plant hormones (except ABA was also observed in roots. The level of this inhibitor depended on N nutrition. Nitrogen bad a similar effect as light on the growth and initiation of needles and lateral roots. However, it strongly inhibited elongation of roots and increased the water content of the tissues. In needles N increased the level of GAs and auxins, under both light variants, as well as the level of cytokinins, under more intensive light. It decreased the amount of ABA-like inhibitor. In roots the effect of N nutrition on the level of plant hormones depended upon the light intensity. Under light of low intensity N decreased the level of GAs and ABA, increased the level of auxins and had nonsignificant influence on the level of cytokinins. Under more intensive light it had no effect on the GAs and auxin levels and increased the level of cytoikinins and the ABA-like inhibitor.

  9. Generation of intense circularly polarized attosecond light bursts from relativistic laser plasmas

    CERN Document Server

    Ma, Guangjin; Yu, M Y; Shen, Baifei; Veisz, Laszlo

    2016-01-01

    We have investigated the polarization of attosecond light bursts generated by nanobunches of electrons from relativistic few-cycle laser pulse interaction with the surface of overdense plasmas. Particle-in-cell simulation shows that the polarization state of the generated attosecond burst depends on the incident-pulse polarization, duration, carrier envelope phase, as well as the plasma scale length. Through laser and plasma parameter control, without compromise of generation efficiency, a linearly polarized laser pulse with azimuth $\\theta^i=10^\\circ$ can generate an elliptically polarized attosecond burst with azimuth $|\\theta^r_{\\rm atto}|\\approx61^\\circ$ and ellipticity $\\sigma^r_{\\rm atto}\\approx0.27$; while an elliptically polarized laser pulse with $\\sigma^i\\approx0.36$ can generate an almost circularly polarized attosecond burst with $\\sigma^r_{\\rm atto}\\approx0.95$. The results propose a new way to a table-top circularly polarized XUV source as a probe with attosecond scale time resolution for many a...

  10. PSB27: A thylakoid protein enabling Arabidopsis to adapt to changing light intensity

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Xin [Univ. of California, Berkeley, CA (United States). Dept of Plant and Microbial Biology; Garcia, Veder J. [Univ. of California, Berkeley, CA (United States). Dept of Plant and Microbial Biology; Buchanan, Bob B. [Univ. of California, Berkeley, CA (United States). Dept of Plant and Microbial Biology; Luan, Sheng [Univ. of California, Berkeley, CA (United States). Dept of Plant and Microbial Biology

    2016-08-22

    Project Title: Immunophilins in the assembly and maintenance of photosynthetic electron transport chain in Arabidopsis Applicant: The Regents of the University of California PI: Sheng Luan, University of California at Berkeley Photosynthetic light energy conversion entails coordinated function of complex molecular machines that capture and convert light energy into chemical forms through photosynthetic electron transport chain. Each molecular machine, such as photosystem II (PSII), may consist of dozens of protein subunits and small molecule cofactors. Despite advanced understanding of the structure and function of these complexes, little is known about “How individual proteins and cofactors assemble into a functional machine and how do these molecular machines maintain their structure and function under a highly hazardous lumenal environment.” Our studies on immunophilins have unexpectedly contributed to the understanding of this question. Originally defined as cellular receptors for immunosuppressants, immunophilins have been discovered in a wide range of organisms from bacteria, fungi, plants, to animals. Immunophilins function in protein folding processes as chaperones and foldases. Arabidopsis genome encodes ca. 50 immunophilins. The most striking finding is that 16 immunophilin members are targeted to chloroplast thylakoid lumen, by far the largest group in the lumenal proteome. What is the function of immunophilins in the thylakoid lumen? Our studies have demonstrated critical roles for several immunophilins in the biogenesis and maintenance of photosynthetic complexes such as PSII. These studies have made a critical link between immunophilins and the assembly of photosynthetic machines and thus opened up a new area of research in photosynthesis. Our goal is to dissect the roles of immunophilins and their partners in the assembly and maintenance of the photosynthetic electron transport chain. The specific objectives for this funding period will be: 1. To

  11. A new high dynamic range ROIC with smart light intensity control unit

    Science.gov (United States)

    Yazici, Melik; Ceylan, Omer; Shafique, Atia; Abbasi, Shahbaz; Galioglu, Arman; Gurbuz, Yasar

    2017-05-01

    This journal presents a new high dynamic range ROIC with smart pixel which consists of two pre-amplifiers that are controlled by a circuit inside the pixel. Each pixel automatically decides which pre-amplifier is used according to the incoming illumination level. Instead of using single pre-amplifier, two input pre-amplifiers, which are optimized for different signal levels, are placed inside each pixel. The smart circuit mechanism, which decides the best input circuit according to the incoming light level, is also designed for each pixel. In short, an individual pixel has the ability to select the best input amplifier circuit that performs the best/highest SNR for the incoming signal level. A 32 × 32 ROIC prototype chip is designed to demonstrate the concept in 0.18 μ m CMOS technology. The prototype is optimized for NIR and SWIR bands. Instead of a detector, process variation optimized current sources are placed inside the ROIC. The chip achieves minimum 8.6 e- input referred noise and 98.9 dB dynamic range. It has the highest dynamic range in the literature in terms of analog ROICs for SWIR band. It is operating in room temperature and power consumption is 2.8 μ W per pixel.

  12. Morphologic Changes of Zebrafish Melanophore after Intense Pulsed Light and Q-Switched Nd:YAG Laser Irradiation

    Science.gov (United States)

    Ryu, Hwa Jung; Lee, Ji Min; Jang, Hee Won; Park, Hae Chul; Rhyu, Im Joo

    2016-01-01

    Background Recently, the pulse-in-pulse mode of intense pulsed light (IPL) has been used increasingly for the treatment of melasma. Objective To observe the morphologic changes in the melanophore in adult zebrafish after irradiation with conventional and pulse-in-pulse IPL and Q-switched Nd:YAG (QSNY) laser. Methods Adult zebrafish were irradiated with conventional and pulse-in-pulse mode of IPL. The conditions for conventional IPL were 3 mJ/cm2, 560 nm filter, and pulse widths of 7, 20, and 35 msec. The pulse-in-pulse conditions were 3 mJ/cm2 and on-time 1/off-time 2. The QSNY laser was used with the settings of 1,064 nm, 0.4 J/cm2, a 7 mm spot size, and one shot. Specimens were observed using a light microscope, a transmission electron microscope (TEM), a scanning electron microscope (SEM) and a confocal microscope. Results After conventional IPL irradiation with a 7 msec pulse width, melanophore breakage was observed using light microscopy. Under TEM, irradiation with conventional IPL for 7 msec and pulse-in-pulse IPL induced melanophore thermolysis with vacuolization. However, changes in the melanophore were not observed with 35 msec IPL. Under SEM, unlike the control and QSNY groups, IPL-irradiated zebrafish showed finger-like fusion in the protein structure of scales. Specimens examined by a confocal microscope after conventional IPL irradiation showed a larger green-stained area on TUNEL staining than that after pulse-in-pulse mode IPL irradiation. Conclusion Zebrafish irradiated with long pulse-IPL showed no morphologic changes using light microscopy, while morphological changes in melanophores were evident with use of TEM. Pulse-in-pulse mode IPL caused less damage than conventional IPL. PMID:27904270

  13. Matrix formalism for calculation of the light beam intensity in stratified multilayered films, and its use in the analysis of emission spectra.

    Science.gov (United States)

    Ohta, K; Ishida, H

    1990-06-01

    Matrix formulation to describe the light propagation in stratified multilayered films has been extended to a system with phase incoherence. Several equations for the reflectance, transmittance, and light beam intensity in the film system are derived from the formulation. Some formulas previously proposed are corrected in reference to the present method. The beam intensity description is used for the calculation of light emissive power from multilayered films having a temperature gradient. It is found that the equations derived here are exactly equivalent to those derived from the radiative transfer equation. However, the present method is more tractable, and can be readily used for a film system with any number of layers.

  14. Roll-to-roll-compatible, flexible, transparent electrodes based on self-nanoembedded Cu nanowires using intense pulsed light irradiation

    Science.gov (United States)

    Zhong, Zhaoyang; Woo, Kyoohee; Kim, Inhyuk; Hwang, Hyewon; Kwon, Sin; Choi, Young-Man; Lee, Youngu; Lee, Taik-Min; Kim, Kwangyoung; Moon, Jooho

    2016-04-01

    Copper nanowire (Cu NW)-based flexible transparent conductive electrodes (FTCEs) have been investigated in detail for use in various applications such as flexible touch screens, organic photovoltaics and organic light-emitting diodes. In this study, hexadecylamine (HDA) adsorbed onto the surface of NWs is changed into polyvinylpyrrolidone (PVP) via a ligand exchange process; the high-molecular-weight PVP enables high dispersion stability. Intense pulsed light (IPL) irradiation is used to remove organic species present on the surface of the NWs and to form direct connections between the NWs rapidly without any atmospheric control. NWs are self-nanoembedded into a plastic substrate after IPL irradiation, which results in a smooth surface, strong NW/substrate adhesion, excellent mechanical flexibility and enhanced oxidation stability. Moreover, Cu NW FTCEs with high uniformities are successfully fabricated on a large area (150 mm × 200 mm) via successive IPL irradiation that is synchronized with the motion of the sample stage. This study demonstrates the possibility of roll-to-roll-based, large-scale production of low-cost, high-performance Cu NW-based FTCEs.Copper nanowire (Cu NW)-based flexible transparent conductive electrodes (FTCEs) have been investigated in detail for use in various applications such as flexible touch screens, organic photovoltaics and organic light-emitting diodes. In this study, hexadecylamine (HDA) adsorbed onto the surface of NWs is changed into polyvinylpyrrolidone (PVP) via a ligand exchange process; the high-molecular-weight PVP enables high dispersion stability. Intense pulsed light (IPL) irradiation is used to remove organic species present on the surface of the NWs and to form direct connections between the NWs rapidly without any atmospheric control. NWs are self-nanoembedded into a plastic substrate after IPL irradiation, which results in a smooth surface, strong NW/substrate adhesion, excellent mechanical flexibility and enhanced

  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 intensity at the return place and encirclement power ratio for the distorted reflected beam based on cat-eye effect

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yan-zhong; SUN Hua-yan; ZHANG Lai-xian; ZHENG Yong-hui

    2011-01-01

    Based on the definition of second order moment and the approximate three-dimensional analytical formula for probe detected laser beam passing through a cat-eye optical lens with center shelter and oblique detector,the analytical expression of the encirclement power ratio of the cat-eye effect reflected light under far-field condition has been deduced.Variable laws of light intensity at the return place and encirclement power ratio are performed by numerical calculation,and are analyzed physically.The results show that the light intensity at the return place decreases monotonically with the increases of the diameter,incidence angle,tilted angle of the detector and the center shelter ratio,but the relationships between these parameters and the encirclement power ratio are all nonmonotonic.The reasonable choice of the focal shift size would result in the largest light intensity at the return place and the largest erirclenent power ratio.

  17. Effect of kinetin and chloramphenicol on chlorophyll synthesis and chloroplast development in detached lupin cotyledons under low light intensity

    Directory of Open Access Journals (Sweden)

    Fortunat Młodzianowski

    2015-01-01

    Full Text Available Chlorophyll synthesis in detached lupin cotyledons under low light intensity was stimulated by kinetin at 20 mg/l and inhibited by chloramphenicol at 50 mg/1. Kinetin not only conteracted the inhibitory effect of chloramphenicol, but stimulated1 the chlorophyll syntesis to a greater level than in the control material. Kinetin accelerated the starch degradation and the development of chloroplast; its prolonged, action, however, produced some abnormalities, such as an excessive growth of plastids resulting in some cases in bursting of their envelopes, the formation and release f r om plastids of numerous membrane - bound bodies and the accumulation in released and swollen thylakoids of electron - dense substance. In the presence of chloramphenicol, some disturbances in structure of the stroma thylakoids and the appearance of vesicular structures in the stroma and the enlargement of grana and swelling of their thylakoids were observed. Kinetin prevented some of these abnormalities.

  18. An intense reddish-orange emitting Eu2SiS4:Er3+ for light emitting diodes

    Science.gov (United States)

    Zhang, Gongguo; Lu, Xifeng; Hu, Ang

    2017-09-01

    An intense reddish-orange phosphor, Eu2SiS4:Er3+, was developed. The photoluminescence excitation and emission spectra, the lifetime, and the concentration effect are investigated. The results show that an efficient energy transfer occurs from Eu2+ to Er3+, and its efficiency is about 81.0%. The phosphors exhibit an efficient broad absorption band and give reddish-orange emitting light with higher color purity. These results demonstrate that Er3+ ion with low 4f - 4f absorption efficiency can play a role of activator in narrow reddish-orange emitting phosphor, potentially useful in n-UV/blue GaN-based LED through efficient energy feeding by a strong excitation band of Eu2+.

  19. Optical coherence photoacoustic microscopy (OC-PAM) with an intensity-modulated continuous-wave broadband light source

    Science.gov (United States)

    Liu, Xiaojing; Wen, Rong; Li, Yiwen; Jiao, Shuliang

    2016-06-01

    We developed an optical coherence photoacoustic microscopy system using an intensity-modulated continuous-wave superluminescent diode with a center wavelength of 840 nm. The system can accomplish optical coherence tomography (OCT) and photoacoustic microscopy (PAM) simultaneously. Compared to the system with a pulsed light source, this system is able to achieve OCT imaging with quality as high as conventional spectral-domain OCT. Since both of the OCT and PAM images are generated from the same group of photons, they are intrinsically registered in the lateral directions. The system was tested for multimodal imaging the vasculature of mouse ear in vivo by using gold nanorods as contrast agent for PAM, as well as excised porcine eyes ex vivo. The OCT and PAM images showed complimentary information of the sample.

  20. Dimer formation in radiation-irradiated aqueous solution of lysozyme studied by light-scattering-intensity measurement

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, S.; Masuda, T.; Kondo, M. (Institute of Physical and Chemical Research, Wako, Saitama (Japan); Tokyo Metropolitan Univ. (Japan). Faculty of Science); Seki, H.; Imamura, M. (Institute of Physical and Chemical Research, Wako, Saitama (Japan))

    1981-07-01

    The reaction of lysozyme with OH radical, Br/sub 2/ anion radical, and e/sup -/sub(aq), produced in an aqueous solution by pulsed electrons and ..gamma..-rays, were investigated. Irradiated enzymes showed an increase in the light scattering intensity (LSI) which is proportional to the absorbed dose. Results obtained from SDS gel electrophoresis confirm dimerization of lysozyme, which is considered to be responsible for the increase in LSI. It was found that the rate constant of the dimerization of protein radicals produced in the reaction with OH radical is 2k = (1.0+-0.3) x 10/sup 6/M/sup -1/s/sup -1/ and the yield of the dimerization is 0.6 in G. The enzymatic activity of the dimer is shown to be reduced to about 30 per cent of that of the intact enzyme. It is concluded that the radiation-induced inactivation of lysozyme is largely due to dimerization.

  1. Dimer formation in radiation-irradiated aqueous solution of lysozyme studied by light-scattering-intensity measurement.

    Science.gov (United States)

    Hashimoto, S; Seki, H; Masuda, T; Imamura, M; Kondo, M

    1981-07-01

    The reaction of lysozyme with OH., Br.-2 and e-aq, produced in an aqueous solution by pulsed electrons and gamma-rays, were investigated. Irradiated enzymes showed an increase in the light scattering intensity (LSI) which is proportional to the absorbed dose. Results obtained from SDS gel electrophoresis confirm dimerization of lysozyme, which is considered to be responsible for the increase in LSI. It was found that the rate constant of the dimerization of protein radicals produced in the reaction with OH. is 2K=(1.0 +/- 0.3) X 10(6)M-1 s-1 and the yield of the dimerization is 0.6 in G. The enzymatic activity of the dimer is shown to be reduced to about 30 per cent of that of the intact enzyme. It is concluded that the radiation-induced inactivation of lysozyme is largely due to dimerization.

  2. The inter-comparison of major satellite aerosol retrieval algorithms using simulated intensity and polarization characteristics of reflected light

    Directory of Open Access Journals (Sweden)

    A. A. Kokhanovsky

    2010-07-01

    Full Text Available Remote sensing of aerosol from space is a challenging and typically underdetermined retrieval task, requiring many assumptions to be made with respect to the aerosol and surface models. Therefore, the quality of a priori information plays a central role in any retrieval process (apart from the cloud screening procedure and the forward radiative transfer model, which to be most accurate should include the treatment of light polarization and molecular-aerosol coupling. In this paper the performance of various algorithms with respect to the of spectral aerosol optical thickness determination from optical spaceborne measurements is studied. The algorithms are based on various types of measurements (spectral, angular, polarization, or some combination of these. It is confirmed that multiangular spectropolarimetric measurements provide more powerful constraints compared to spectral intensity measurements alone, particularly those acquired at a single view angle and which rely on a priori assumptions regarding the particle phase function in the retrieval process.

  3. Effects of Light Intensity and Fertilization on the Growth of Andean Oak Seedlings at Nursery

    Directory of Open Access Journals (Sweden)

    Yira Lucia Sepúlveda

    2014-03-01

    Full Text Available Quercus humboldtii is a native plant species of great importance in Colombia for use in reforestation and restoration of degraded Andean highlands. The species is highly threatened and it is necessary to establish programs of propagation and planting. However, little is known about their nutritional and light requirements. The aim of this study was to determine the effects of single and combined relative illumination (IR and fertilization on the growth of seedlings of  Q. humboldtii at nursery. For this purpose three contrasting IR regimes (high, medium, and low IR and nine fertilization treatments were established: complete (TC, a missing nutrient (-N,-P,-K,-Ca,-Mg, -S,-B and a control without fertilization (T0. The best development of seedlings was showed in the medium IR condition. All treatments with a lacking nutrient showed decreases in seedling development regarding TC, except in the –B treatment. Nitrogen was the most limiting nutrient yielding biomass similar to that of T0. The impact of nutrient limitation on seedling performance was in the following order:-N>-Ca,-K,-P>-Mg,-S>-B. No significant interaction IR x Fertilization was detected on seedling development.EFECTOS DE LA ILUMINACIÓN RELATIVA Y LA FERTILIZACIÓN SOBRE EL CRECIMIENTO DE PLÁNTULAS DE ROBLE ANDINO EN VIVEROQuercus humboldtii es una especie vegetal nativa de mucha importancia en Colombia por su uso en repoblamiento forestal y restauración de tierras altoandinas degradadas. La especie se encuentra fuertemente amenazada y es necesario establecer programas de propagación de la misma. Sin embargo, poco se conoce sobre sus exigencias nutricionales y lumínicas. El objetivo de este estudio fue determinar los efectos simples y combinados de la iluminación relativa (IR y la fertilización sobre el crecimiento de plántulas de  Q. humboldtii en vivero. Para esto se establecieron en combinación tres condiciones contrastantes de iluminación relativa (alta, media y baja

  4. On the light intensity transmitted through water and aqueous supersaturated ammonium dihydrogen phosphate solutions containing different antisolvents

    Science.gov (United States)

    Sangwal, Keshra

    2017-02-01

    Experimental data of the dependence of transmitted laser light intensity I of aqueous ADP solutions saturated at 303.15 K on feeding time t of three antisolvents (i.e. acetone, methanol and ethanol) are analyzed using mathematical equations based on two approaches. The first approach is based on exponential decrease in I with increasing t whereas the second one is based on the concept of adsorption of antisolvent molecules onto solvent and solute molecules. It was found that: (1) the latter approach is superior to the former one for explaining the observed dependence of transmitted laser-beam intensities of pure solvent and aqueous saturated ADP solutions, (2) the parameter A of the second approach provides better insight into the processes of adsorption of antisolvents in terms of the differential heat Qdiff of adsorption, and (3) the trends of changes in the values Qdiff for different antisolvents in water and aqueous solutions are associated with the dielectric constants of different antisolvents and are directly connected with the chemical constitution of the methanol, ethanol and acetone molecules.

  5. Dynamic oxidation of gaseous mercury in the Arctic troposphere at polar sunrise

    DEFF Research Database (Denmark)

    Lindberg, Steve E; Brooks, Steve; Lin, C J

    2002-01-01

    Gaseous elemental mercury (Hg0) is a globally distributed air toxin with a long atmospheric residence time. Any process that reduces its atmospheric lifetime increases its potential accumulation in the biosphere. Our data from Barrow, AK, at 71 degrees N show that rapid, photochemically driven...... oxidation of boundary-layer Hg0 after polar sunrise, probably by reactive halogens, creates a rapidly depositing species of oxidized gaseous mercury in the remote Arctic troposphere at concentrations in excess of 900 pg m(-3). This mercury accumulates in the snowpack during polar spring at an accelerated...

  6. Precise numerical evaluation of the two loop sunrise graph Master Integrals in the equal mass case

    CERN Document Server

    Pozzorini, Stefano

    2006-01-01

    We present a double precision routine in Fortran for the precise and fast numerical evaluation of the two Master Integrals (MIs) of the equal mass two-loop sunrise graph for arbitrary momentum transfer in d=2 and d=4 dimensions. The routine implements the accelerated power series expansions obtained by solving the corresponding differential equations for the MIs at their singular points. With a maximum of 22 terms for the worst case expansion a relative precision of better than a part in 10^{15} is achieved for arbitrary real values of the momentum transfer.

  7. 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...

  8. 1,213 Cases of Treatment of Facial Acne Using Indocyanine Green and Intense Pulsed Light in Asian Skin

    Directory of Open Access Journals (Sweden)

    Kui Young Park

    2015-01-01

    Full Text Available Background. Photodynamic therapy (PDT has been used for acne, with various combinations of photosensitizers and light sources. Objective. We evaluated the effectiveness and safety of indocyanine green (ICG and intense pulsed light (IPL in the treatment of acne. Materials and Methods. A total of 1,213 patients with facial acne were retrospectively reviewed. Patients received three or five treatments of ICG and IPL at two-week intervals. Clinical response to treatment was assessed by comparing pre- and posttreatment clinical photographs and patient satisfaction scores. Results. Marked to excellent improvement was noted in 483 of 1,213 (39.8% patients, while minimal to moderate improvement was achieved in the remaining 730 (60.2% patients. Patient satisfaction scores revealed that 197 (16.3% of 1,213 patients were highly satisfied, 887 (73.1% were somewhat satisfied, and 129 (10.6% were unsatisfied. There were no significant side effects. Conclusion. These results suggest that PDT with ICG and IPL can be effectively and safely used in the treatment of acne.

  9. How diffusivity, thermocline and incident light intensity modulate the dynamics of deep chlorophyll maximum in Tyrrhenian Sea.

    Science.gov (United States)

    Valenti, Davide; Denaro, Giovanni; Spagnolo, Bernardo; Conversano, Fabio; Brunet, Christophe

    2015-01-01

    During the last few years theoretical works have shed new light and proposed new hypotheses on the mechanisms which regulate the spatio-temporal behaviour of phytoplankton communities in marine pelagic ecosystems. Despite this, relevant physical and biological issues, such as effects of the time-dependent mixing in the upper layer, competition between groups, and dynamics of non-stationary deep chlorophyll maxima, are still open questions. In this work, we analyze the spatio-temporal behaviour of five phytoplankton populations in a real marine ecosystem by using a one-dimensional reaction-diffusion-taxis model. The study is performed, taking into account the seasonal variations of environmental variables, such as light intensity, thickness of upper mixed layer and profiles of vertical turbulent diffusivity, obtained starting from experimental findings. Theoretical distributions of phytoplankton cell concentration was converted in chlorophyll concentration, and compared with the experimental profiles measured in a site of the Tyrrhenian Sea at four different times (seasons) of the year, during four different oceanographic cruises. As a result we find a good agreement between theoretical and experimental distributions of chlorophyll concentration. In particular, theoretical results reveal that the seasonal changes of environmental variables play a key role in the phytoplankton distribution and determine the properties of the deep chlorophyll maximum. This study could be extended to other marine ecosystems to predict future changes in the phytoplankton biomass due to global warming, in view of devising strategies to prevent the decline of the primary production and the consequent decrease of fish species.

  10. 1,213 Cases of Treatment of Facial Acne Using Indocyanine Green and Intense Pulsed Light in Asian Skin.

    Science.gov (United States)

    Park, Kui Young; Kim, Ji Young; Hyun, Moo Yeol; Oh, Won Jong; Jeong, Se Yeong; Han, Tae Young; Ahn, Ji Young; Kim, Beom Joon; Kim, Myeung Nam

    2015-01-01

    Photodynamic therapy (PDT) has been used for acne, with various combinations of photosensitizers and light sources. We evaluated the effectiveness and safety of indocyanine green (ICG) and intense pulsed light (IPL) in the treatment of acne. A total of 1,213 patients with facial acne were retrospectively reviewed. Patients received three or five treatments of ICG and IPL at two-week intervals. Clinical response to treatment was assessed by comparing pre- and posttreatment clinical photographs and patient satisfaction scores. Marked to excellent improvement was noted in 483 of 1,213 (39.8%) patients, while minimal to moderate improvement was achieved in the remaining 730 (60.2%) patients. Patient satisfaction scores revealed that 197 (16.3%) of 1,213 patients were highly satisfied, 887 (73.1%) were somewhat satisfied, and 129 (10.6%) were unsatisfied. There were no significant side effects. These results suggest that PDT with ICG and IPL can be effectively and safely used in the treatment of acne.

  11. Fast fabrication of copper nanowire transparent electrodes by a high intensity pulsed light sintering technique in air.

    Science.gov (United States)

    Ding, Su; Jiu, Jinting; Tian, Yanhong; Sugahara, Tohru; Nagao, Shijo; Suganuma, Katsuaki

    2015-12-14

    Copper nanowire transparent electrodes have received increasing interest due to the low price and nearly equal electrical conductivity compared with other TEs based on silver nanowires and indium tin oxide (ITO). However, a post-treatment at high temperature in an inert atmosphere or a vacuum environment was necessary to improve the conductivity of Cu NW TEs due to the easy oxidation of copper in air atmosphere, which greatly cancelled out the low price advantage of Cu NWs. Here, a high intensity pulsed light technique was introduced to sinter and simultaneously deoxygenate these Cu NWs into a highly conductive network at room temperature in air. The strong light absorption capacity of Cu NWs enabled the welding of the nanowires at contact spots, as well as the removal of the thin layer of residual organic compounds, oxides and hydroxide of copper even in air. The Cu NW TE with a sheet resistance of 22.9 Ohm sq(-1) and a transparency of 81.8% at 550 nm has been successfully fabricated within only 6 milliseconds exposure treatment, which is superior to other films treated at high temperature in a hydrogen atmosphere. The HIPL process was simple, convenient and fast to fabricate easily oxidized Cu NW TEs in large scale in an air atmosphere, which will largely extend the application of cheap Cu NW TEs.

  12. [Effects of light intensity heterogeneity in gaps of broadleaved Korean pine forest in Changbai Mountains on Pinus koraiensis seedings growth].

    Science.gov (United States)

    Wang, Zhuo; Fan, Xiu-Hua

    2009-05-01

    By using a Li-6400 portable photosynthesis system, this paper studied the heterogeneity of light intensity in four different size gaps of a broadleaved Korean pine forest in Changbai Mountains, and analyzed the diurnal change of the photosynthesis of Pinus koraiensis saplings in the gaps. In the nine orientations within the gaps, the peak value of the photosynthetically active radiation (PAR) varied in the sequence of west of actual gap, north of extended gap, gap center > south of actual gap, south of extended gap, east of extended gap, east of actual gap > west of extended gap, north of actual gap. Light distribution was dissymmetry in the orientations of east-west and south-north, with the variation in west and north being more significant than that in other orientations. There was no significant difference in the average PAR among the positions within specific orientations. The average PAR of the four gaps from I to IV was 21.85, 45.57, 66.02, and 23.48 micromol x m(-2) x s(-1), respectively, and the difference was statistically significant (P < 0.05). PAR had a significant positive correlation with net photosynthetic rate (P(n)), and the correlation coefficient increased with increasing PAR. With the increase of gap size, both the PAR and the P(n) of P. koraiensis saplings increased first and decreased then, with the maximum values appeared at 267 m2 of gap size.

  13. 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.

  14. Application of immobilized TiO2 photocatalysis to improve the inactivation of Heterosigma akashiwo in ballast water by intense pulsed light.

    Science.gov (United States)

    Feng, Daolun; Xu, Shihong; Liu, Gang

    2015-04-01

    Ballast water exotic discharge has been identified as a leading vector for marine species invasion. Here immobilized TiO2 photocatalysis is introduced to improve the performance of intense pulsed light. For intense pulsed light/TiO2 photocatalysis, a typical inactivation of 99.89±0.46% can be achieved under treatment condition of 1.78 L min(-1) flow rate, 300 V pulse peak voltage, 15 Hz pulse frequency and 5 ms pulse width. Moreover, within tested 220-260 V peak voltage, 18.37-40.51% elevation in inactivation is observed in comparison with intense pulsed light treatment alone. The rough energy consumption of the tested intense pulsed light/TiO2 treatment system is about 1.51-2.51 times higher than that of the typical commercial UV ballast water treatment system. The stability of the photocatalytic reactivity and intactness of loaded TiO2 film is proved within 20-d's test, while local erosion on stainless steel support is observed after 30-d's test. The results indicate that intense pulsed light/TiO2 photocatalysis is likely to be a competitive ballast water treatment technique, while further measures is needed to reduce the energy consumption and ensure the performance of TiO2 film in a long run.

  15. Sub-lambda gratings, surface plasmons, hotter electrons and brighter x-ray sources- enhanced absorption of intense, ultrashort laser light by tiny surface modulations

    CERN Document Server

    Kahaly, S; Kahaly, Subhendu

    2007-01-01

    We observe near 100 % absorption of light in intense ultrashort laser plasma interaction in a metal coated (Au on glass) sub-lambda grating structure under suitable conditions and the subsequent 'hot' electron generation from the grating plasma. In the low intensity regime we determine the conditions in which a monochromatic infrared light (lambda = 800nm corresponding to the central wavelength of the ultrashort laser that we used in subsequent experiments) efficiently excites surface plasmon in the grating. Then we study how the surface plasmon resonance condition changes when we excite them using low intensity ultrashort pulses. We look at the reflectivity of light varying the incident light intensity over a wide range (2x10e12Wcm-2-2x10e15Wcm-2). The reflectivity of grating with the resonance condition satisfied is the lowest over the whole range of intensity. We compare the data with those obtained from highly polished (lambda/5) Au mirror target under identical conditions. At high intensities we look at ...

  16. Fast algal eco-toxicity assessment: Influence of light intensity and exposure time on Chlorella vulgaris inhibition by atrazine and DCMU.

    Science.gov (United States)

    Camuel, Alexandre; Guieysse, Benoit; Alcántara, Cynthia; Béchet, Quentin

    2017-06-01

    In order to develop a rapid assay suitable for algal eco-toxicity assessments under conditions representative of natural ecosystems, this study evaluated the short-term (atrazine and DCMU using oxygen productivity measurements. When Chlorella vulgaris was exposed to these herbicides under 'standard' low light intensity (as prescribed by OECD201 guideline), the 20min-EC50 values recorded via oxygen productivity (atrazine: 1.32±0.07μM; DCMU: 0.31±0.005μM) were similar the 96-h EC50 recorded via algal growth (atrazine: 0.56μM; DCMU: 0.41μM), and within the range of values reported in the literature. 20min-EC50 values increased by factors of 3.0 and 2.1 for atrazine and DCMU, respectively, when light intensity increased from 60 to 1400μmolm(-2)s(-1) of photosynthetically active radiation, or PAR. Further investigation showed that exposure time significantly also impacted the sensitivity of C. vulgaris under high light intensity (>840μmolm(-2)s(-1) as PAR) as the EC50 for atrazine and DCMU decreased by up to 6.2 and 2.1 folds, respectively, after 50min of exposure at a light irradiance of 1400μmolm(-2)s(-1) as PAR. This decrease was particularly marked at high light intensities and low algae concentrations and is explained by the herbicide disruption of the electron transfer chain triggering photo-inhibition at high light intensities. Eco-toxicity assessments aiming to understand the potential impact of toxic compounds on natural ecosystems should therefore be performed over sufficient exposure times (>20min for C. vulgaris) and under light intensities relevant to these ecosystems. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Effects of light radiation intensity on photosynthetic characteristics and water use efficiency of Platycladus orientalis and Pinus tabulaeformis seedlings

    Institute of Scientific and Technical Information of China (English)

    ZHANG Weiqiang; HE Kangning; WANG Yunqi; WANG Baitian; DENG Juntao; ZHOU Yi; ZHONG Xijun; LI Zhaoqing

    2007-01-01

    In order to offer a scientific basis for cultivation and management of forests,effects of light radiation intensity on photosynthetic characteristics and water use efficiency of Platycladus orientalis and Pinus tabulaeformis were studied under different soil moisture contents.By adopting artificial control methods to soil moisture,and under simulated photosynthetic radiation (SPR),the net photosynthetic rate (PN),transpiration rate (Tr),water use efficiency (WUE) and intercellular CO2 concentration (Ci,) of Platycladus orientalis and Pinus tabulaeformis in the semi-arid region of the Loess Plateau,were studied.Results are as follows:within the photon range of 0-2,200 μmol/(m2·s),PN,Tr and WUE were enhanced with an increase in SPR in both species.PN and WUE of Platycladus orientalis and Pinus tabulaeformis,however,declined with continued increase in SPR.PN,Tr,WUE and light saturation point (LSP) of Platycladus orientalis were higher than those of Pinus tabulaeformis,while light compensation point (LCP) of Platycladus orientalis was lower than that of Pinus tabulaeformis at the same soil moisture content.The efficiency of light energy utilization of Platycladus orientalis was higher than that of Pinus tabulaeformis;PN,Tr and Ci of Platycladus orientalis and Pinus tabulaeformis were enhanced by increasing soil moisture content,whereas WUE declined.At soil moistures of 7.90%,13.00% and 19.99%,LSP of Platycladus orientalis LCP was 42,25 and 13 μmol/(m2·s) respectively,with corresponding maximal net CO2 photosynthetic rates (Pmax)of 3.04,4.06 and 5.53 μmol(m2·s).At soil moistures of 7.83%,13.04% and 20.15%, the LSP of Pinus tabulaeformis was 1,100, 1,325 and 1,500 μmol/(m2·s) respectively and LCP was 60,30 and 23μmol/(m2·s), with Pmas of 1.08, 3.35 and 4.36 μmol/(m2·s)respectively.

  18. Light intensity and quality from sole-source light-emitting diodes impact growth, morphology, and nutrient content of Brassica microgreens

    Science.gov (United States)

    Multi-layer vertical production systems using sole-source (SS) lighting can be used for microgreen production; however, traditional SS lighting can consume large amounts of electrical energy. Light-emitting diodes (LEDs) offer many advantages over conventional light sources including: high photoelec...

  19. Light intensity, photoperiod duration, daily light flux and coral growth of Galaxea fascicularis in an aquarium setting: a matter of photons?

    NARCIS (Netherlands)

    Schutter, M.; Ven, R.M.; Janse, M.; Verreth, J.A.J.; Wijffels, R.H.; Osinga, R.

    2012-01-01

    Light is one of the most important abiotic factors influencing the (skeletal) growth of scleractinian corals. Light stimulates coral growth by the process of light-enhanced calcification, which is mediated by zooxanthellar photosynthesis. However, the quantity of light that is available for daily

  20. Light intensity, photoperiod duration, daily light flux and coral growth of Galaxea fascicularis in an aquarium setting: a matter of photons?

    NARCIS (Netherlands)

    Schutter, M.; Ven, R.M.; Janse, M.; Verreth, J.A.J.; Wijffels, R.H.; Osinga, R.

    2012-01-01

    Light is one of the most important abiotic factors influencing the (skeletal) growth of scleractinian corals. Light stimulates coral growth by the process of light-enhanced calcification, which is mediated by zooxanthellar photosynthesis. However, the quantity of light that is available for daily co

  1. Kinetic characteristics and modeling of microalgae Chlorella vulgaris growth and CO2 biofixation considering the coupled effects of light intensity and dissolved inorganic carbon.

    Science.gov (United States)

    Chang, Hai-Xing; Huang, Yun; Fu, Qian; Liao, Qiang; Zhu, Xun

    2016-04-01

    Understanding and optimizing the microalgae growth process is an essential prerequisite for effective CO2 capture using microalgae in photobioreactors. In this study, the kinetic characteristics of microalgae Chlorella vulgaris growth in response to light intensity and dissolved inorganic carbon (DIC) concentration were investigated. The greatest values of maximum biomass concentration (Xmax) and maximum specific growth rate (μmax) were obtained as 2.303 g L(-1) and 0.078 h(-1), respectively, at a light intensity of 120 μmol m(-2) s(-1) and DIC concentration of 17 mM. Based on the results, mathematical models describing the coupled effects of light intensity and DIC concentration on microalgae growth and CO2 biofixation are proposed. The models are able to predict the temporal evolution of C. vulgaris growth and CO2 biofixation rates from lag to stationary phases. Verification experiments confirmed that the model predictions agreed well with the experimental results.

  2. Online Ephemerides – the Equation of Time and True Solar Time, Sunrise and Sunset and the Corresponding Azimuths

    Directory of Open Access Journals (Sweden)

    Goran Tomac

    2015-12-01

    Full Text Available The paper describes the Croatian web page Online ephemerides with its applications for calculating and visualising the equation of time and the analemma, converting zone time (zone or civil time into true solar time (the time shown by sundials and calculating the time of sunrise and sunset and the corresponding azimuths. The calculated values for the equation of time, ephemeris transit and the true solar time of ±4 seconds, sunrise and sunset times of ±30 seconds and the azimuth of ±30” must meet the accuracy needed by both amateur and professional astronomers. The web applications described are also adapted for smart phones.

  3. Low light intensity effects on the growth, photosynthetic characteristics, antioxidant capacity, yield and quality of wheat (Triticum aestivum L.) at different growth stages in BLSS

    Science.gov (United States)

    Dong, Chen; Fu, Yuming; Liu, Guanghui; Liu, Hong

    2014-06-01

    Minimizing energy consumption and maximizing crop productivity are major challenges to growing plants in Bioregenerative Life Support System (BLSS) for future long-term space mission. As a primary source of energy, light is one of the most important environmental factors for plant growth. The purpose of this study is to investigate the effects of low light intensity at different stages on growth, pigment composition, photosynthetic efficiency, biological production and antioxidant defence systems of wheat (Triticum aestivum L.) cultivars during ontogenesis. Experiments were divided into 3 intensity-controlled stages according to growth period (a total of 65 days): seedling stage (first 20 days), heading and flowering stage (middle 30 days) and grain filling stage (last 15 days). Initial light condition of the control was 420 μmol m-2 s-1 and the light intensity increased with the growth of wheat plants. The light intensities of group I and II at the first stage and the last stage were adjusted to the half level of the control respectively. For group III, the first and the last stage were both adjusted to half level of the control. During the middle 30 days, all treatments were kept the same intensity. The results indicated that low-light treatment at seedling stage, biomass, nutritional contents, components of inedible biomass and healthy index (including peroxidase (POD) activity, malondialdehyde (MDA) and proline content) of wheat plants have no significant difference to the control. Furthermore, unit kilojoule yield of group I reached 0.591 × 10-3 g/kJ and induced the highest energy efficiency. However, low-light treatment at grain filling stage affected the final production significantly.

  4. Guidelines of care for vascular lasers and intense pulse light sources from the European Society for Laser Dermatology.

    Science.gov (United States)

    Adamič, M; Pavlović, M D; Troilius Rubin, A; Palmetun-Ekbäck, M; Boixeda, P

    2015-09-01

    Lasers and non-coherent intense pulse light sources (IPLS) are based on the principle of selective photothermolysis and can be used for the treatment of many vascular skin lesions. A variety of lasers has been developed for the treatment of congenital and acquired vascular lesions which incorporate these concepts into their design. Although laser and light sources are very popular due to their non-invasive nature, caution should be considered by practitioners and patients to avoid permanent side-effects. The aim of these guidelines is to give evidence-based recommendations for the use of lasers and IPLS in the treatment of vascular lesions. These guidelines were produced by a Consensus Panel made up of experts in the field of vascular laser surgery under the auspices of the European Society of Laser Dermatology. Recommendations on the use of vascular lasers and IPLS were made based on the quality of evidence for efficacy, safety, tolerability, cosmetic outcome, patient satisfaction/preference and, where appropriate, on the experts' opinion. The recommendations of these guidelines are graded according to the American College of Chest Physicians Task Force recommendations on Grading Strength of Recommendations and Quality of Evidence in Clinical Guidelines. Lasers and IPLS are very useful and sometimes the only available method to treat various vascular lesions. It is of a paramount importance that the type of laser or IPLS and their specific parameters are adapted to the indication but also that the treating physician is familiar with the device to be used. The crucial issue in treating vascular lesions is to recognize the immediate end-point after laser treatment. This is the single most important factor to ensure both the efficacy of the treatment and avoidance of serious side-effects. © 2015 European Academy of Dermatology and Venereology.

  5. Efficacy of Intense Pulsed Light Therapy in the Treatment of Facial Acne Vulgaris: Comparison of Two Different Fluences

    Science.gov (United States)

    Patidar, Monika V; Deshmukh, Ashish Ramchandra; Khedkar, Maruti Yadav

    2016-01-01

    Background: Acne vulgaris is the most common disease of the skin affecting adolescents and young adults causing psychological distress. The combination of antibiotic resistance, adverse effects of topical and systemic anti acne medications and desire for high tech approaches have all led to new enthusiasm for light based acne treatment. Intense pulse light (IPL) therapy has three modes of action in acne vulgaris i.e., photochemical, photo thermal and photo immunological. Aims: (1) to study efficacy of IPL therapy in facial acne vulgaris. (2) To compare two fluences - one normal and other subnormal on right and left side of face respectively. Methods: (Including settings and design and statistical analysis used). Total 45 patients in age group 16 to 28 years with inflammatory facial acne vulgaris were included in prospective study. Baseline data for each patient was recorded. All patients were given 4 sittings of IPL at 2 weeks interval and were followed for 2 months every 2 weeks. Fluence used was 35J/cm2 on right and 20J/cm2 on left side. Percentage reduction in lesion count was calculated at each sitting and follow up and graded as mild (0-25%), moderate (26-50%), good (51-75%) and excellent (76-100%). Side effects were noted. The results were analysed using Mann-Whitney Test. Results: On right side, excellent results were achieved in 10(22%), good in 22(49%) and moderate in 13(29%) patients. On left side excellent were results achieved in 7(15%), good in 19(42%) and moderate in 16(43%) patients. There was no statically significant difference noted in efficacy of two fluences used in treatment of facial acne vulgaris. Conclusions: IPL is a effective and safe option for inflammatory acne vulgaris with minimal reversible side effects. Subnormal fluence is as effective as normal fluence in Indian skin. PMID:27688446

  6. Efficacy of intense pulsed light therapy in the treatment of facial acne vulgaris: Comparison of two different fluences

    Directory of Open Access Journals (Sweden)

    Monika V Patidar

    2016-01-01

    Full Text Available Background: Acne vulgaris is the most common disease of the skin affecting adolescents and young adults causing psychological distress. The combination of antibiotic resistance, adverse effects of topical and systemic anti acne medications and desire for high tech approaches have all led to new enthusiasm for light based acne treatment. Intense pulse light (IPL therapy has three modes of action in acne vulgaris i.e., photochemical, photo thermal and photo immunological. Aims: (1 to study efficacy of IPL therapy in facial acne vulgaris. (2 To compare two fluences - one normal and other subnormal on right and left side of face respectively. Methods: (Including settings and design and statistical analysis used. Total 45 patients in age group 16 to 28 years with inflammatory facial acne vulgaris were included in prospective study. Baseline data for each patient was recorded. All patients were given 4 sittings of IPL at 2 weeks interval and were followed for 2 months every 2 weeks. Fluence used was 35J/cm2 on right and 20J/cm2 on left side. Percentage reduction in lesion count was calculated at each sitting and follow up and graded as mild (0-25%, moderate (26-50%, good (51-75% and excellent (76-100%. Side effects were noted. The results were analysed using Mann-Whitney Test. Results: On right side, excellent results were achieved in 10(22%, good in 22(49% and moderate in 13(29% patients. On left side excellent were results achieved in 7(15%, good in 19(42% and moderate in 16(43% patients. There was no statically significant difference noted in efficacy of two fluences used in treatment of facial acne vulgaris. Conclusions: IPL is a effective and safe option for inflammatory acne vulgaris with minimal reversible side effects. Subnormal fluence is as effective as normal fluence in Indian skin.

  7. Interactive influence of leaf age, light intensity, and girdling on green ash foliar chemistry and emerald ash borer development.

    Science.gov (United States)

    Chen, Yigen; Poland, Therese M

    2009-07-01

    Biotic and abiotic environmental factors affect plant nutritional quality and defensive compounds that confer plant resistance to herbivory. Influence of leaf age, light availability, and girdling on foliar nutrition and defense of green ash (Fraxinus pennsylvanica Marsh) was examined in this study. Longevity of the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), adults reared on green ash foliage subjected to these factors was assayed. Mature leaves generally were more nutritious with greater amino acids and a greater ratio of protein to non-structural carbohydrate (P:C) than young leaves, in particular when trees were grown in shade. On the other hand, mature leaves had lower amounts of trypsin and chymotrypsin inhibitors, and total phenolics compared to young leaves. Lower defense of mature leaves alone, or along with higher nutritional quality may lead to increased survival and longevity of emerald ash borer feeding on mature leaves. Sunlight reduced amino acids and P:C ratio, irrespective of leaf age and girdling, and elevated total protein of young foliage, but not protein of mature leaves. Sunlight also dramatically increased all investigated defensive compounds of young, but not mature leaves. Girdling reduced green ash foliar nutrition, especially, of young leaves grown in shade and of mature leaves grown in sun. However emerald ash borer performance did not differ when fed leaves from trees grown in sun or shade, or from girdled or control trees. One explanation is that emerald ash borer reared on lower nutritional quality food may compensate for nutrient deficiency by increasing its consumption rate. The strong interactions among leaf age, light intensity, and girdling on nutrition and defense highlight the need for caution when interpreting data without considering possible interactions.

  8. Effects of Light Intensity on Germination of Light Sensitive and Insensitive Tobacco Seed%光照强度对光敏感型和光不敏感型烟草种子发芽的影响

    Institute of Scientific and Technical Information of China (English)

    宋碧清; 郑昀晔; 马文广; 李元君; 牛永志; 索文龙

    2013-01-01

    为研究光照强度对光敏感型和光不敏感型烟草种子发芽的影响,选用19个烟草品种种子分别于光照和黑暗条件下发芽,筛选出光照敏感型品种NC297、光照较敏感型品种NC102和光照不敏感型品种MS云烟87、云烟97等。以光照敏感型品种NC297和光照不敏感型品种MS云烟87种子为材料,研究其在不同光照强度下的发芽情况。结果表明,2个类型的种子发芽势、发芽率以及发芽指数均随着光照强度的增强而提高,当光照强度超过3730 lx后,又逐渐降低,发芽时间则呈相反趋势。研究认为光敏感型和光不敏感型烟草种子发芽的最适光照强度均为3730 lx。%To study the effects of light intensity on germination of light sensitive and insensitive tobacco seed, seeds of 19 cultivars were germinated under light and dark conditions. The results showed that seed germination varied with tobacco cultivars under dark condition. According to the cluster analysis, 19 tobacco cultivars were clustered into three groups: light sensitive cultivar, intermediate light sensitive cultivar and light insensitive cultivar. NC297 and MS Yunyan 87 were used as the light sensitive cultivar and the light insensitive cultivar to study the effects of light intensity on tobacco seed germination. The results showed that the seed germination energy, germination percentage and germination index of the two cultivars increased with the enhancement of light intensity, and reduced gradually when the light intensity was more than 3730 lx. The reverse case was found in germination time. It can be concluded that the best light intensity for light sensitive and insensitive tobacco seed germination is 3730 lx.

  9. Measurement of water column primary production using photosynthesis-irradiance relations for surface phytoplankton, the vertical chlorophyll profile, and underwater light intensity

    Science.gov (United States)

    Demidov, A. B.; Gagarin, V. I.; Mosharov, S. A.

    2016-09-01

    A method has been developed to measure water column integrated primary production (PPint) in the water column using photosynthesis-irradiance relations for surface phytoplankton, the vertical profile of chlorophyll a concentration, and the underwater light intensity. Good correlation has been found for the results calculated with this method and light dependences in situ. The advantages of this method are the independence of PPint calculation from CTD profiling and water sampling, and thus optimization (reduction) of the station working time.

  10. Recent Developments of Versatile Photoinitiating Systems for Cationic Ring Opening Polymerization Operating at Any Wavelengths and under Low Light Intensity Sources.

    Science.gov (United States)

    Lalevée, Jacques; Mokbel, Haifaa; Fouassier, Jean-Pierre

    2015-04-20

    Photoinitiators (PI) or photoinitiating systems (PIS) usable in light induced cationic polymerization (CP) and free radical promoted cationic polymerization (FRPCP) reactions (more specifically for cationic ring opening polymerization (ROP)) together with the involved mechanisms are briefly reviewed. The recent developments of novel two- and three-component PISs for CP and FRPCP upon exposure to low intensity blue to red lights is emphasized in details. Examples of such reactions under various experimental conditions are provided.

  11. Sunrise as a tourist attraction in the context of tourist motivation theory: a case study of the peak of Babia Góra (Western Carpathians

    Directory of Open Access Journals (Sweden)

    Mocior Ewelina

    2015-12-01

    Full Text Available Tourist ascents of mountain peaks before sunrise are increasingly popular. Babia Góra (Western Carpathians is a peak on the Polish-Slovak border frequently visited by a great number of tourists at sunrise. The main objective of our research, based on the case study of Babia Gora, was to answer a more general question whether the sunrise can be considered a tourist attraction. The research included the observation and description of every sunrise at summer holiday weekends during 2012 from the peak of Babia Góra as well as the collection of data on the number of tourists and weather conditions. Survey interviews, using questionnaire, with randomly selected hikers present on the peak of Babia Góra at sunrise (269 were conducted. The investigation showed that during summer holiday sunrises there were a maximum of 130 people on the summit of Babia Góra at the same time. Most of the surveyed people (84% agreed that the opportunity to observe the sunrise was one of the pull factors for them. This confirms the hypothesis that sunrise constitutes a tourist attraction.

  12. Leaf plasticity to light intensity in Italian cypress (Cupressus sempervirens L.): adaptability of a Mediterranean conifer cultivated in the Alps.

    Science.gov (United States)

    Baldi, Paolo; Muthuchelian, Krishnasamy; La Porta, Nicola

    2012-12-05

    Italian cypress (Cupressus sempervirens L.) is native to the eastern Mediterranean, an area characterised by hot, dry summers and mild winters. Over the centuries, however, the species has been introduced into more northerly regions, a long way from its native range. The current, generally warmer climatic conditions brought about by global warming have favoured its cultivation in even more northerly areas in the Alps and other European alpine regions. Given that not only temperature, but also light availability are limiting factors for the spread of cypress in these environments, it is important to ascertain how this species copes with low light conditions. The photosynthetic characteristics of cypress leaves collected from different portions of the crown with contrasting light availability were evaluated by several methods. Chlorophyll a (Chl a), chlorophyll b (Chl b) and carotenoid (Car) content was found to be higher in shade leaves than in sun leaves when measured on a fresh mass basis, although enzymatic activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) and nitrate reductase were lower in shade leaves. When the efficiency of PSII was measured by chlorophyll fluorescence, a marked reduction in F(m) was found in shade leaves, while F(o) remained unchanged. The use of exogenous electron donors diphenyl carbazide (DPC) and NH(2)OH actually improved the photosynthetic efficiency of shade leaves, and the same effect was found when PSII electron transport activity was measured as O(2) evolution. Altogether, these results seem to indicate lesser photosynthetic efficiency in shade leaves, probably an impairment on the donor side of the PSII. At the same time, analysis by SDS-PAGE revealed differences in the polypeptide composition of the thylakoid membranes of sun and shade leaves: the bands corresponding to 23 kDa, 28-25 kDa and 33 kDa polypeptides were less intense in the thylakoid membranes extracted from shade leaves. These results were

  13. Effects of spectral composition, photoperiod and light intensity on the gonadal development of Atlantic salmon Salmo salar in recirculating aquaculture systems (RAS)

    Science.gov (United States)

    Qiu, Denggao; Xu, Shihong; Song, Changbin; Chi, Liang; Li, Xian; Sun, Guoxiang; Liu, Baoliang; Liu, Ying

    2015-01-01

    Artificial lighting regimes have been successfully used to inhibit sexual maturity of Atlantic salmon in confinement. However, when these operations are applied in commercial recirculating aquaculture systems (RAS) using standard lighting technology, sexual maturation is not suppressed. In this study, an L9 (33) orthogonal design was used to determine the effects of three factors (spectral composition, photoperiod, and light intensity) on the gonadal development of Atlantic salmon in RAS. We demonstrated that the photoperiod at the tested levels had a much greater effect on the gonadosomatic index and female Fulton condition factor than spectral composition and light intensity. The photoperiod had a significant effect on the secretion of sex steroids and melatonin ( P0.05). The optimum lighting levels in female and male Atlantic salmon were LD 8:16, 455 nm (or 625 nm), 8.60 W/m2; and LD 8:16, 8.60 W/m2, 455 nm respectively. These conditions not only delayed gonadal development, but also had no negative effects on Atlantic salmon growth in RAS. These results demonstrate that a combination of spectral composition, photoperiod and light intensity is effective at delaying the gonadal development of both male and female salmon in RAS.

  14. Intense Pulsed Light and Low-Fluence Q-Switched Nd:YAG Laser Treatment in Melasma Patients

    Science.gov (United States)

    Na, Se Young; Cho, Soyun

    2012-01-01

    Background Recently, low fluence collimated Q-switched (QS) Nd:YAG laser has drawn attention for the treatment of melasma. However, it needs a lot of treatment sessions for the substantial results and repetitive laser exposures may end up with unwanted depigmentation. Objective We evaluated the clinical effects and safety of the combinational treatment, using intense pulsed light (IPL) and low fluence QS Nd:YAG laser. Methods Retrospective case series of 20 female patients, with mixed type melasma, were analyzed using medical records. They were treated with IPL one time, and 4 times of weekly successive low fluence Nd:YAG laser treatments. At each visit, digital photographs were taken under the same condition. Melanin index (MI) and erythema index (EI) were measured on the highest point on the cheekbones. Modified melasma area and severity index (MASI) scores were calculated by two investigators using digital photographs. Results The mean values of MI and EI decreased significantly after treatments. The modified MASI score has decreased by 59.35%, on average. Sixty percents of the participants did not require any more treatments, and no clinical aggravations were observed during the follow-up period (mean 5.9 months). Conclusion IPL and low fluence laser may elicit a clinical resolution in the mixed type melasma with long term benefits. PMID:22879709

  15. Significant reduction of inflammation and sebaceous glands size in acne vulgaris lesions after intense pulsed light treatment.

    Science.gov (United States)

    Barakat, Manal T; Moftah, Noha H; El Khayyat, Mohammad A M; Abdelhakim, Zainab A

    2017-01-01

    Intense pulsed light (IPL) has been used for years in treatment of acne vulgaris. However, quantitative evaluation of histopathological changes after its use as a sole therapy was poorly investigated. Accordingly, this study aims to objectively evaluate inflammatory infiltrate and sebaceous glands in acne vulgaris after IPL. Twenty-four patients of acne were treated with six IPL sessions. Clinical evaluation was done at 2 weeks after last session by counting acne lesions. Patient satisfaction using Cardiff Acne Disability Index (CADI) was recorded at baseline, 2 weeks and 3 months after IPL. Using histopathological and computerized morphometric analysis, quantitative evaluation of inflammatory infiltrate and measurement of surface area of sebaceous glands were performed for skin biopsies at baseline and 2 weeks after last session. After IPL, there was significant reduction of all acne lesions especially inflammatory variety with significant decrease of CADI score at 2 weeks and 3 months after IPL (p acne vulgaris especially inflammatory variety. The results suggest that IPL could improve acne lesions through targeting both inflammation and sebaceous glands.

  16. Effects of temperature, CO 2/O 2 concentrations and light intensity on cellular multiplication of microalgae, Euglena gracilis

    Science.gov (United States)

    Kitaya, Y.; Azuma, H.; Kiyota, M.

    Microalgae culture is likely to play an important role in aquatic food production modules in bioregenerative systems for producing feeds for fish, converting CO 2 to O 2 and remedying water quality as well as aquatic higher plants. In the present study, the effects of culture conditions on the cellular multiplication of microalgae, Euglena gracilis, was investigated as a fundamental study to determine the optimum culture conditions for microalgae production in aquatic food production modules including both microalgae culture and fish culture systems. E. gracilis was cultured under conditions with five levels of temperatures (25-33 °C), three levels of CO 2 concentrations (2-6%), five levels of O 2 concentrations (10-30%), and six levels of photosynthetic photon flux (20-200 μmol m -2 s -1). The number of Euglena cells in a certain volume of solution was monitored with a microscope under each environmental condition. The multiplication rate of the cells was highest at temperatures of 27-31 °C, CO 2 concentration of 4%, O 2 concentration of 20% and photosynthetic photon flux of about 100 μmol m -2 s -1. The results demonstrate that E. gracilis could efficiently produce biomass and convert CO 2 to O 2 under relatively low light intensities in aquatic food production modules.

  17. Comparison of tubular and panel type photobioreactors for biohydrogen production utilizing Chlamydomonas reinhardtii considering mixing time and light intensity.

    Science.gov (United States)

    Oncel, S; Kose, A

    2014-01-01

    Two different photobioreactor designs; tubular and panel, were investigated for the biohydrogen production utilizing a green microalgae Chlamydomonas reinhardtii strain CC124 following the two stage protocol. Mixing time and light intensity of the systems were adjusted to compare the productivity of both aerobic culture phase and the following anaerobic biohydrogen production phase. The results showed there was an effect on both phases related with the design. During the aerobic phase bigger illumination area serving more energy, tubular photobioreactor reached higher biomass productivity of 31.8±2.1 mg L(-1) h(-1) which was about 11% higher than the panel photobioreactor. On the other hand biohydrogen productivity in the panel photobioreactor reached a value of 1.3±0.05 mL L(-1) h(-1) based on the efficient removal of biohydrogen gas. According to the results it would be a good approach to utilize tubular design for aerobic phase and panel for biohydrogen production phase.

  18. Effects of Culture Media and Light Intensity on in vitro Growth of Oncidium under CO2 Enrichment Condition

    Institute of Scientific and Technical Information of China (English)

    He Songlin; Pan Huitang; Yang Qiusheng; Kong Dezheng; Zhang Qixiang; Michio Tanaka

    2003-01-01

    The effects of culture media and light intensity on in vitro growth of Oncidium 'Aloha Iwanga' were investigated under CO2 enrichment condition. Height, fresh and dry weight of the Oncidium seedlings were measured, and the leaf number per plant, shoot number per plant, leaf width and leaf chlorophyll content were also investigated. The results were as follows: 1) The seedling height, fresh and dry weight, leaf number per plant, leaf width and leaf chlorophyll content of the shoots growing on MS complete culture medium were higher than those on 1/2MS, VW and 1/2VW media. The root number per plant and ratio of dry matter of the seedlings cultured on 1/2MS and 1/2VW media were higher than those on MS and VW; 2) The seedling height, fresh weight, dry weight, dry matter ratio and leaf chlorophyll content, leaf length, leaf width, root length, leaf number per plant, root number per plant of seedlings of Oncidium growing under 4 500 lx and 1 700 lx were higher than those under 750 lx. However, there was no significant difference in those growth parameters mentioned above while dealing with 4 500 lx and 1 700 lx except for the seedling height. Nevertheless, the leaf color of plants under 4 500 lx was lighter and the leaves of the lower parts became yellowish in comparison with those growing under 1 700 lx.

  19. Room temperature synthesis of a copper ink for the intense pulsed light sintering of conductive copper films.

    Science.gov (United States)

    Dharmadasa, Ruvini; Jha, Menaka; Amos, Delaina A; Druffel, Thad

    2013-12-26

    Conducting films are becoming increasingly important for the printed electronics industry with applications in various technologies including antennas, RFID tags, photovoltaics, flexible electronics, and displays. To date, expensive noble metals have been utilized in these conductive films, which ultimately increases the cost. In the present work, more economically viable copper based conducting films have been developed for both glass and flexible PET substrates, using copper and copper oxide nanoparticles. The copper nanoparticles (with copper(I) oxide impurity) are synthesized by using a simple copper reduction method in the presence of Tergitol as a capping agent. Various factors such as solvent, pH, and reductant concentration have been explored in detail and optimized in order to produce a nanoparticle ink at room temperature. Second, the ink obtained at room temperature was used to fabricate conducting films by intense pulse light sintering of the deposited films. These conducting films had sheet resistances as low as 0.12 Ω/□ over areas up to 10 cm(2) with a thickness of 8 μm.

  20. Effect of vegetal cover on runoff and soil erosion under light intensity events. Rainfall simulation over USLE plots.

    Science.gov (United States)

    Marques, María José; Bienes, Ramón; Jiménez, Luis; Pérez-Rodríguez, Raquel

    2007-05-25

    The erosive power of frequent light rainfalls is studied in this paper. Field experiments of simulated rainfall (Intensity, 21 mm h(-1) and kinetic energy, 13.5 J m(-2) mm(-1)) were conducted over 8 bounded USLE plots (80 m(2) each) with a slope of 10%. In 4 plots the soil was almost bare (<4% vegetation cover); the other 4 plots had almost full cover with natural vegetation in one year. Runoff and sediment yield was recorded. The results revealed the efficiency of vegetation cover reducing runoff and sediments. Runoff and sediments were negligible in covered plots. Therefore, in bare plots, although sediment yield was generally low, averaging 74+/-43 kg ha(-1), the mean of runoff achieved a coefficient of 35%, this magnitude has to be taken into consideration in this region verging on aridity. Rains around 13.5 J m(-2) mm(-1) of kinetic energy are quite frequent in the study area (34% of recorded rains en 12 years). If we would consider the usual lower limits from the literature, we would be ignoring an important percent of natural rainfall episodes.

  1. Combinations of High Intensity Light Pulses and Thermosonication for the inactivation of Escherichia coli in orange juice.

    Science.gov (United States)

    Muñoz, A; Palgan, I; Noci, F; Morgan, D J; Cronin, D A; Whyte, P; Lyng, J G

    2011-09-01

    The non-thermal technologies High Intensity Light Pulses (HILP) and Thermosonication (TS) were applied alone and in combination to study their effect on Escherichia coli inactivation in orange juice. Two different energy settings were chosen in the current study, 'Low' (L) and 'High' (H), being the combinations applied: HILP(L) (4.03 J/cm(2)), HILP(H) (5.1 J/cm(2)), TS(L) (2.8 min residence time at 40 °C) and TS(H) (5 min residence time at 50 °C). Both the individual technologies and their combinations (HILP&TS and TS&HILP) were studied. Results showed inactivation ranging from 1.10 (TS(H)) to 2.42 (HILP(H)) log cfu/ml for the hurdles when applied individually and from 2.5 (HILP(L)&TS(H)) to 3.93 (HILP(H)&TS(L)) log cfu/ml for the combined treatments. Similar reductions in E. coli populations were achieved in orange juice by all treatment combinations irrespective of the sequence in which they were applied. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Image Tracking for the High Similarity Drug Tablets Based on Light Intensity Reflective Energy and Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Zhongwei Liang

    2014-01-01

    Full Text Available It is obvious that tablet image tracking exerts a notable influence on the efficiency and reliability of high-speed drug mass production, and, simultaneously, it also emerges as a big difficult problem and targeted focus during production monitoring in recent years, due to the high similarity shape and random position distribution of those objectives to be searched for. For the purpose of tracking tablets accurately in random distribution, through using surface fitting approach and transitional vector determination, the calibrated surface of light intensity reflective energy can be established, describing the shape topology and topography details of objective tablet. On this basis, the mathematical properties of these established surfaces have been proposed, and thereafter artificial neural network (ANN has been employed for classifying those moving targeted tablets by recognizing their different surface properties; therefore, the instantaneous coordinate positions of those drug tablets on one image frame can then be determined. By repeating identical pattern recognition on the next image frame, the real-time movements of objective tablet templates were successfully tracked in sequence. This paper provides reliable references and new research ideas for the real-time objective tracking in the case of drug production practices.

  3. Effects of temperature, CO2/O2 concentrations and light intensity on cellular multiplication of microalgae, Euglena gracilis

    Science.gov (United States)

    Kitaya, Y.; Azuma, H.; Kiyota, M.

    2005-01-01

    Microalgae culture is likely to play an important role in aquatic food production modules in bioregenerative systems for producing feeds for fish, converting CO2 to O2 and remedying water quality as well as aquatic higher plants. In the present study, the effects of culture conditions on the cellular multiplication of microalgae, Euglena gracilis, was investigated as a fundamental study to determine the optimum culture conditions for microalgae production in aquatic food production modules including both microalgae culture and fish culture systems. E. gracilis was cultured under conditions with five levels of temperatures (25-33 degrees C), three levels of CO2 concentrations (2-6%), five levels of O2 concentrations (10-30%), and six levels of photosynthetic photon flux (20-200 micromoles m-2 s-1). The number of Euglena cells in a certain volume of solution was monitored with a microscope under each environmental condition. The multiplication rate of the cells was highest at temperatures of 27-31 degrees C, CO2 concentration of 4%, O2 concentration of 20% and photosynthetic photon flux of about 100 micromoles m-2 s-1. The results demonstrate that E. gracilis could efficiently produce biomass and convert CO2 to O2 under relatively low light intensities in aquatic food production modules. c2005 Published by Elsevier Ltd on behalf of COSPAR.

  4. 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.

  5. The effects of low-intensity narrow-band blue-light treatment compared to bright white-light treatment in sub-syndromal seasonal affective disorder

    NARCIS (Netherlands)

    Meesters, Ybe; Winthorst, Wim H.; Duijzer, Wianne; Bos, Elisabeth; V, Hommes,

    2016-01-01

    Background The discovery of a novel photoreceptor in the retinal ganglion cells with a highest sensitivity of 470-490 nm blue light has led to research on the effects of short-wavelength light in humans. Several studies have explored the efficacy of monochromatic blue or blue-enriched light in the

  6. The effects of low-intensity narrow-band blue-light treatment compared to bright white-light treatment in sub-syndromal seasonal affective disorder

    OpenAIRE

    Meesters, Ybe; Winthorst, Wim H; Duijzer, Wianne B.; Hommes, Vanja

    2016-01-01

    Background The discovery of a novel photoreceptor in the retinal ganglion cells with a highest sensitivity of 470-490 nm blue light has led to research on the effects of short-wavelength light in humans. Several studies have explored the efficacy of monochromatic blue or blue-enriched light in the treatment of SAD. In this study, a comparison has been made between the effects of broad-wavelength light without ultraviolet (UV) wavelengths compared to narrow-band blue light in the treatment of ...

  7. The effects of low-intensity narrow-band blue-light treatment compared to bright white-light treatment in sub-syndromal seasonal affective disorder

    OpenAIRE

    Meesters, Ybe; Winthorst, Wim H; Duijzer, Wianne; Bos, Elisabeth; V, Hommes,

    2016-01-01

    Background The discovery of a novel photoreceptor in the retinal ganglion cells with a highest sensitivity of 470-490 nm blue light has led to research on the effects of short-wavelength light in humans. Several studies have explored the efficacy of monochromatic blue or blue-enriched light in the treatment of SAD. In this study, a comparison has been made between the effects of broad-wavelength light without ultraviolet (UV) wavelengths compared to narrow-band blue light in the treatment of ...

  8. Heme oxygenase 2 of the cyanobacterium Synechocystis sp. PCC 6803 is induced under a microaerobic atmosphere and is required for microaerobic growth at high light intensity.

    Science.gov (United States)

    Yilmaz, Mete; Kang, Ilgu; Beale, Samuel I

    2010-01-01

    Cyanobacteria, red algae, and cryptomonad algae utilize phycobilin chromophores that are attached to phycobiliproteins to harvest solar energy. Heme oxygenase (HO) in these organisms catalyzes the first step in phycobilin formation through the conversion of heme to biliverdin IXalpha, CO, and iron. The Synechocystis sp. PCC 6803 genome contains two open reading frames, ho1 (sll1184) and ho2 (sll1875), whose products have in vitro HO activity. We report that HO2, the protein encoded by ho2, was induced in the cells growing under a microaerobic atmosphere [0.2% (v/v) O(2)], whereas HO1 was constitutively expressed under both aerobic and microaerobic atmospheres. Light intensity did not have an effect on the expression of both the HOs. Cells, in which ho2 was disrupted, were unable to grow microaerobically at a light intensity of 40 micromol m(-2) s(-1), but did grow microaerobically at 10 micromol m(-2) s(-1) light intensity. These cells grew normally aerobically at both light intensities. Comparative analysis of complete cyanobacterial genomes revealed that possession of two HOs is common in cyanobacteria. In phylogenetic analysis of their amino acid sequences, cyanobacterial HO1 and HO2 homologs formed distinct clades. HO sequences of cyanobacteria that have only one isoform were most similar to HO1 sequences. We propose that HO2 might be the more ancient HO homolog that functioned under low O(2) tension, whereas the derived HO1 can better accommodate increased O(2) tension in the environment.

  9. Growth and content of Spirulina platensis biomass chlorophyll cultivated at different values of light intensity and temperature using different nitrogen sources

    Directory of Open Access Journals (Sweden)

    Eliane Dalva Godoy Danesi

    2011-03-01

    Full Text Available The effects of light intensity and temperature in S. platensis cultivation with potassium nitrate or urea as nitrogen source were investigated, as well as the biomass chlorophyll contents of this cyanobacteria, through the Response Surface Methodology. Experiments were performed at temperatures from 25 to 34.5ºC and light intensities from 15 to 69 µmol photons m-2 s-1, in mineral medium. In cultivations with both sources of nitrogen, KNO3 and urea, statistic evaluation through multiple regression, no interactions of such independent variables were detected in the results of the dependent variables maximum cell concentration, chlorophyll biomass contents, cell and chlorophyll productivities, as well as in the nitrogen-cell conversion factor. In cultivation performed with both sources of nitrogen, it was possible to obtain satisfactory adjustments to relate the dependent variables to the independent variables. The best results were achieved at temperature of 30ºC, at light intensity of 60 µmol photons m-2s-1, for cell growth, with cell productivity of approximately 95 mg L-1 d-1 in cultivations with urea. For the chlorophyll biomass content, the most adequate light intensity was 24 µmol photons m-2 s-1.

  10. Effects of light intensity on Tropical Soda Apple and the consequences for performance of its biological control agent, Gratiana boliviana (Chrysomelidae).

    Science.gov (United States)

    The current research was directed at determining the impact of light intensity on the architecture, amino acid content and trichome density and characteristics of Tropical Soda Apple (TSA), Solanum viarum (Solanaceae). TSA plants were grown in a greenhouse either covered with a shade cloth (75% bloc...

  11. Paring and intense pulsed light versus paring alone for recalcitrant hand and foot warts: a randomized clinical trial with blinded outcome evaluation

    DEFF Research Database (Denmark)

    Togsverd-Bo, Katrine; Gluud, Christian; Winkel, Per

    2010-01-01

    Treatment of recalcitrant viral warts remains a therapeutic challenge. Intense pulsed light (IPL) has been suggested effective to clear wart tissue. The objective was in a randomized controlled trial to assess the efficacy of paring followed by IPL versus paring alone for recalcitrant hand and foot...... warts....

  12. Growth and Content of Spirulina Platensis Biomass Chlorophyll Cultivated at Different Values of Light Intensity and Temperature Using Different Nitrogen Sources

    Science.gov (United States)

    Godoy Danesi, Eliane Dalva; Oliveira Rangel-Yagui, Carlota; Sato, Sunao; Monteiro de Carvalho, João Carlos

    2011-01-01

    The effects of light intensity and temperature in S. platensis cultivation with potassium nitrate or urea as nitrogen source were investigated, as well as the biomass chlorophyll contents of this cyanobacteria, through the Response Surface Methodology. Experiments were performed at temperatures from 25 to 34.5ºC and light intensities from 15 to 69 µmol photons m−2 s−1, in mineral medium. In cultivations with both sources of nitrogen, KNO3 and urea, statistic evaluation through multiple regression, no interactions of such independent variables were detected in the results of the dependent variables maximum cell concentration, chlorophyll biomass contents, cell and chlorophyll productivities, as well as in the nitrogen-cell conversion factor. In cultivation performed with both sources of nitrogen, it was possible to obtain satisfactory adjustments to relate the dependent variables to the independent variables. The best results were achieved at temperature of 30ºC, at light intensity of 60 µmol photons m−2s−1, for cell growth, with cell productivity of approximately 95 mg L−1 d−1 in cultivations with urea. For the chlorophyll biomass content, the most adequate light intensity was 24 µmol photons m−2 s−1. PMID:24031643

  13. Intense pulsed light vs. long-pulsed dye laser treatment of telangiectasia after radiotherapy for breast cancer: a randomized split-lesion trial of two different treatments

    DEFF Research Database (Denmark)

    Nymann, P.; Hedelund, L.; Hædersdal, Merete

    2009-01-01

    Background Chronic radiodermatitis is a common sequela of treatment for breast cancer and potentially a psychologically distressing factor for the affected women. Objectives To evaluate the efficacy and adverse effects of treatments with a long-pulsed dye laser (LPDL) vs. intense pulsed light (IPL...

  14. Paring and intense pulsed light versus paring alone for recalcitrant hand and foot warts: a randomized clinical trial with blinded outcome evaluation

    DEFF Research Database (Denmark)

    Togsverd-Bo, Katrine; Gluud, Christian; Winkel, Per

    2010-01-01

    Treatment of recalcitrant viral warts remains a therapeutic challenge. Intense pulsed light (IPL) has been suggested effective to clear wart tissue. The objective was in a randomized controlled trial to assess the efficacy of paring followed by IPL versus paring alone for recalcitrant hand and foot...

  15. F-15B ACTIVE with thrust vectoring nozzles on test stand at sunrise

    Science.gov (United States)

    1995-01-01

    This November 13, 1995, photograph of the F-15 Advanced Controls Technology for Integrated Vehicles (ACTIVE) at NASA's Dryden Flight Research Center, Edwards, California, shows the aircraft on a test stand at sunrise. Not shown in this photograph are the aircraft's two new Pratt & Whitney nozzles that can turn up to 20 degrees in any direction. These nozzles give the aircraft thrust control in the pitch (up and down) and yaw (left and right) directions. This will reduce drag and increase fuel economy or range as compared with conventional aerodynamic controls, which increase the retarding forces (drag) acting upon the aircraft. These tests could result in significant performance increases for military and commercial aircraft. The research program is the product of a collaborative effort by NASA, the Air Force's Wright Laboratory, Pratt & Whitney, and McDonnell Douglas Aerospace. The aircraft was originally built as an F-15B (Serial #71-0290).

  16. Supersonic Magnetic Upflows in Granular Cells Observed with Sunrise/IMaX

    CERN Document Server

    Borrero, J M; Schlichenmaier, R; Solanki, S K; Bonet, J A; Iniesta, J C del Toro; Schmidt, W; Barthol, P; Gandorfer, A; Domingo, V; Knoelker, M

    2010-01-01

    Using the IMaX instrument on-board the Sunrise stratospheric balloon-telescope we have detected extremely shifted polarization signals around the Fe I 5250.217 {\\AA} spectral line within granules in the solar photosphere. We interpret the velocities associated with these events as corresponding to supersonic and magnetic upflows. In addition, they are also related to the appearance of opposite polarities and highly inclined magnetic fields. This suggests that they are produced by the reconnection of emerging magnetic loops through granular upflows. The events occupy an average area of 0.046 arcsec$^2$ and last for about 80 seconds, with larger events having longer lifetimes. These supersonic events occur at a rate of $1.3\\times10^{-5}$ occurrences per second per arcsec$^{2}$.

  17. Statistical evolution of quiet-Sun small scale magnetic features using Sunrise observations

    CERN Document Server

    Anusha, L S; Hirzberger, Johann; Feller, Alex

    2016-01-01

    The evolution of small magnetic features in quiet regions of the Sun provides a unique window to probing solar magneto-convection. Here we analyze small scale magnetic features in the quiet Sun, using the high resolution, seeing-free observations from the Sunrise balloon borne solar observatory. Our aim is to understand the contribution of different physical processes, such as splitting, merging, emergence and cancellation of magnetic fields to the rearrangement, addition and removal of magnetic flux in the photosphere. We employ a statistical approach for the analysis and the evolution studies are carried out using a feature tracking technique. In this paper we provide a detailed description of the feature tracking algorithm that we have newly developed and we present the results of a statistical study of several physical quantities. The results on the fractions of the flux in the emergence, appearance, splitting, merging, disappearance and cancellation qualitatively agrees with other recent studies. To summ...

  18. Changes of alternative oxidase activity, capacity and protein content in leaves of Cucumis sativus wild-type and MSC16 mutant grown under different light intensities.

    Science.gov (United States)

    Florez-Sarasa, Igor; Ostaszewska, Monika; Galle, Alexander; Flexas, Jaume; Rychter, Anna M; Ribas-Carbo, Miquel

    2009-12-01

    In vitro studies demonstrated that alternative oxidase (AOX) is biochemically regulated by a sulfhydryl-disulfide system, interaction with alpha-ketoacids, ubiquinone pool redox state and protein content among others. However, there is still scarce information about the in vivo regulation of the AOX. Cucumis sativus wild-type (WT) and MSC16 mutant plants were grown under two different light intensities and were used to analyze the relationship between the amount of leaf AOX protein and its in vivo capacity and activity at night and day periods. WT and MSC16 plants presented lower total respiration (V(t)), cytochrome oxidase pathway (COP) activity (v(cyt)) and alternative oxidase pathway (AOP) activity (v(alt)) when grown at low light (LL), although growth light intensity did not change the amount of cytochrome oxidase (COX) nor AOX protein. Changes of v(cyt) related to growing light conditions suggested a substrate availability and energy demand control. On the other hand, the total amount of AOX protein present in the tissue does not play a role in the regulation neither of the capacity nor of the activity of the AOP in vivo. Soluble carbohydrates were directly related to the activity of the AOP. However, although differences in soluble sugar contents mostly regulate the capacity of the AOP at different growth light intensities, additional regulatory mechanisms are necessary to fully explain the observed results.

  19. Interactions of carbon and nitrogen metabolism with changing light intensity in natural populations and cultures of planktonic blue-green algae

    Energy Technology Data Exchange (ETDEWEB)

    Ward, A.K.

    1978-01-01

    This study dealt with the factors contributing to the occurrence of blue-green algae in the plankton of lakes. Blue-green algal populations were examined in two different aquatic systems, moderately productive Lawrence Lake and hypereutrophic Wintergreen Lake, with regard to inorganic nitrogen source, light intensity and regime, and species of blue-green algae present. In order to understand the relationship between light and nitrogen source better among natural populations, representative species of blue-green algae, including isolates of Aphanizomenon flos-aquae, Microcystis aeruginosa, and Anabaena flos-aquae, were grown in laboratory cultures under continuously high, variable, and continuously low light at intensities similar to those in the lakes.

  20. Relationship between 3-Methyl-2,4-nonanedione Concentration and Intensity of Light-induced Off-odor in Soy Bean Oil.

    Science.gov (United States)

    Sano, Takashi; Iwahashi, Maiko; Imagi, Jun; Sato, Toshiro; Yamashita, Toshiyuki; Fukusaki, Eiichiro; Bamba, Takeshi

    2016-05-01

    A beany and green off-odor is developed in soy bean oil (SBO) under light-induced oxidative conditions. 3-Methyl-2,4-nonanedione (3-MND) was inferred as the compound responsible for the off-odor. In this study, we designed a simple quantification method for 3-MND in SBO, and evaluated the relationship between the 3-MND concentration and the intensity of the off-odor. 3-MND was analyzed by GC/MS with a thermal desorption unit system. By our method, the 3-MND concentration was found to increase with storage days and the SBO content under light exposure, and there was a high correlation between the measured 3-MND concentration and the intensity of the light-induced off-odor in SBO (R = 0.9586).

  1. Understanding the molecular mechanisms underlying the effects of light intensity on flavonoid production by RNA-seq analysis in Epimedium pseudowushanense B.L.Guo.

    Science.gov (United States)

    Pan, Junqian; Chen, Haimei; Guo, Baolin; Liu, Chang

    2017-01-01

    Epimedium pseudowushanense B.L.Guo, a light-demanding shade herb, is used in traditional medicine to increase libido and strengthen muscles and bones. The recognition of the health benefits of Epimedium has increased its market demand. However, its resource recycling rate is low and environmentally dependent. Furthermore, its natural sources are endangered, further increasing prices. Commercial culture can address resource constraints of it.Understanding the effects of environmental factors on the production of its active components would improve the technology for cultivation and germplasm conservation. Here, we studied the effects of light intensities on the flavonoid production and revealed the molecular mechanism using RNA-seq analysis. Plants were exposed to five levels of light intensity through the periods of germination to flowering, the flavonoid contents were measured using HPLC. Quantification of epimedin A, epimedin B, epimedin C, and icariin showed that the flavonoid contents varied with different light intensity levels. And the largest amount of epimedin C was produced at light intensity level 4 (I4). Next, the leaves under the treatment of three light intensity levels ("L", "M" and "H") with the largest differences in the flavonoid content, were subjected to RNA-seq analysis. Transcriptome reconstruction identified 43,657 unigenes. All unigene sequences were annotated by searching against the Nr, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. In total, 4008, 5260, and 3591 significant differentially expressed genes (DEGs) were identified between the groups L vs. M, M vs. H and L vs. H. Particularly, twenty-one full-length genes involved in flavonoid biosynthesis were identified. The expression levels of the flavonol synthase, chalcone synthase genes were strongly associated with light-induced flavonoid abundance with the highest expression levels found in the H group. Furthermore, 65 transcription factors, including 31

  2. Construction and validation of a tool to Assess the Use of Light Technologies at Intensive Care Units.

    Science.gov (United States)

    Marinho, Pabliane Matias Lordelo; Campos, Maria Pontes de Aguiar; Rodrigues, Eliana Ofélia Llapa; Gois, Cristiane Franca Lisboa; Barreto, Ikaro Daniel de Carvalho

    2016-12-19

    to construct and validate a tool to assess the use of light technologies by the nursing team at Intensive Care Units. methodological study in which the tool was elaborated by means of the psychometric method for construction based on the categorization of health technologies by Merhy and Franco, from the National Humanization Policy, using the Nursing Intervention Classification taxonomy to categorize the domains of the tool. Agreement Percentages and Content Validity Indices were used for the purpose of validation. The result of the application of the Interrater Agreement Percentage exceeded the recommended level of 80%, highlighting the relevance for the proposed theme in the assessment, with an agreement rate of 99%. the tool was validated with four domains (Bond, Autonomy, Welcoming and Management) and nineteen items that assess the use of light technologies at Intensive Care Units. construir e validar um instrumento para avaliação do uso de tecnologias leves, pela equipe de enfermagem, em Unidades de Terapia Intensiva. estudo metodológico no qual o instrumento foi elaborado utilizando o método psicométrico para construção com base na categorização das tecnologias em saúde de Merhy e Franco, da Política Nacional de Humanização, utilizando-se a taxonomia Nursing Intervention Classification para categorizar os domínios do instrumento. Utilizou-se o Percentual de Concordância e o Índice de Validade de Conteúdo (IVC) para validação. o resultado da aplicação do Percentual de Concordância entre os juízes foi superior ao recomendado de 80%, havendo destaque na avaliação da pertinência ao tema proposto, apresentando um percentual de concordância de 99%. o instrumento foi validado com quatro domínios (Vínculo, Autonomia, Acolhimento e Gestão) e dezenove itens que avaliam o uso das tecnologias leves em Unidade de Terapia Intensiva. construir y validar un instrumento para evaluación del uso de tecnologías leves, por el equipo de enfermer

  3. Effect of Light Intensities and Atmospheric Gas Conditions on Biohydrogen Production of Microalgae Isolated from Fisheries Wastewater

    Directory of Open Access Journals (Sweden)

    Mujalin Pholchan

    2017-06-01

    Full Text Available Recently, the fishery farming industry has been developed rapidly due to increasing demand and consumption as well as the depletion of wild fish resources. Production processes in the industry usually generate large amounts of wastewater containing high nutrients, posing a threat to downstream water. However, phytoplankton removal techniques commonly used to counteract the threat, though appearing to have low efficiency, are timeconsuming and less sustainable. Microalgae are photosynthetic microorganisms that convert solar energy into hydrogen. Using the isolated algae from fish farms as a source of renewable energy production could be a promising choice for handling fisheries wastewater in a more efficient manner. However, hydrogen production processes from algae still need more studies as their efficiencies vary between algae species and growth factors. In this work, the efficiency of hydrogen production from Scenedesmus accuminatus and Arthrospira platensis harvested from fish farms under three different light intensity conditions and three atmospheric gas conditions was determined. The results showed that the best conditions for hydrogen production from both species included 24 h darkness and carbon dioxide addition. Under the atmospheric gas combination of 99% argon and 1% carbon dioxide, S. accuminatus could produce hydrogen gas as high as 0.572 mol H2/mgCh h within 12 h, while the highest hydrogen production (0.348 mol H2/mgCh h obtained from A. platensis was found under the atmospheric gas mixture of 98% argon and 2% carbon dioxide. Interestingly, S. accuminatus appeared to produce more hydrogen than A. platensis under the same conditions.

  4. 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...

  5. The effects of low-intensity narrow-band blue-light treatment compared to bright white-light treatment in sub-syndromal seasonal affective disorder.

    Science.gov (United States)

    Meesters, Ybe; Winthorst, Wim H; Duijzer, Wianne B; Hommes, Vanja

    2016-02-18

    The discovery of a novel photoreceptor in the retinal ganglion cells with a highest sensitivity of 470-490 nm blue light has led to research on the effects of short-wavelength light in humans. Several studies have explored the efficacy of monochromatic blue or blue-enriched light in the treatment of SAD. In this study, a comparison has been made between the effects of broad-wavelength light without ultraviolet (UV) wavelengths compared to narrow-band blue light in the treatment of sub-syndromal seasonal affective disorder (Sub-SAD). In a 15-day design, 48 participants suffering from Sub-SAD completed 20-minute sessions of light treatment on five consecutive days. 22 participants were given bright white-light treatment (BLT, broad-wavelength light without UV 10 000 lux, irradiance 31.7 Watt/m(2)) and 26 participants received narrow-band blue light (BLUE, 100 lux, irradiance 1.0 Watt/m(2)). All participants completed daily and weekly questionnaires concerning mood, activation, sleep quality, sleepiness and energy. Also, mood and energy levels were assessed by means of the SIGH-SAD, the primary outcome measure. On day 15, SIGH-SAD ratings were significantly lower than on day 1 (BLT 54.8 %, effect size 1.7 and BLUE 50.7 %, effect size 1.9). No statistically significant differences were found on the main outcome measures. Light treatment is an effective treatment for Sub-SAD. The use of narrow-band blue-light treatment is equally effective as bright white-light treatment. This study was registered in the Dutch Trial Register (Nederlands Trial Register TC =  4342 ) (20-12-2013).

  6. Biological Significance of Photoreceptor Photocycle Length: VIVID Photocycle Governs the Dynamic VIVID-White Collar Complex Pool Mediating Photo-adaptation and Response to Changes in Light Intensity.

    Directory of Open Access Journals (Sweden)

    Arko Dasgupta

    2015-05-01

    Full Text Available Most organisms on earth sense light through the use of chromophore-bearing photoreceptive proteins with distinct and characteristic photocycle lengths, yet the biological significance of this adduct decay length is neither understood nor has been tested. In the filamentous fungus Neurospora crassa VIVID (VVD is a critical player in the process of photoadaptation, the attenuation of light-induced responses and the ability to maintain photosensitivity in response to changing light intensities. Detailed in vitro analysis of the photochemistry of the blue light sensing, FAD binding, LOV domain of VVD has revealed residues around the site of photo-adduct formation that influence the stability of the adduct state (light state, that is, altering the photocycle length. We have examined the biological significance of VVD photocycle length to photoadaptation and report that a double substitution mutant (vvdI74VI85V, previously shown to have a very fast light to dark state reversion in vitro, shows significantly reduced interaction with the White Collar Complex (WCC resulting in a substantial photoadaptation defect. This reduced interaction impacts photoreceptor transcription factor WHITE COLLAR-1 (WC-1 protein stability when N. crassa is exposed to light: The fast-reverting mutant VVD is unable to form a dynamic VVD-WCC pool of the size required for photoadaptation as assayed both by attenuation of gene expression and the ability to respond to increasing light intensity. Additionally, transcription of the clock gene frequency (frq is sensitive to changing light intensity in a wild-type strain but not in the fast photo-reversion mutant indicating that the establishment of this dynamic VVD-WCC pool is essential in general photobiology and circadian biology. Thus, VVD photocycle length appears sculpted to establish a VVD-WCC reservoir of sufficient size to sustain photoadaptation while maintaining sensitivity to changing light intensity. The great diversity

  7. Predawn and high intensity application of supplemental blue light decreases the quantum yield of PSII and enhances the amount of phenolic acids, flavonoids, and pigments in Lactuca sativa.

    Science.gov (United States)

    Ouzounis, Theoharis; Razi Parjikolaei, Behnaz; Fretté, Xavier; Rosenqvist, Eva; Ottosen, Carl-Otto

    2015-01-01

    To evaluate the effect of blue light intensity and timing, two cultivars of lettuce [Lactuca sativa cv. "Batavia" (green) and cv. "Lollo Rossa" (red)] were grown in a greenhouse compartment in late winter under natural light and supplemental high pressure sodium (SON-T) lamps yielding 90 (±10) μmol m(-2) s(-1) for up to 20 h, but never between 17:00 and 21:00. The temperature in the greenhouse compartments was 22/11°C day/night, respectively. The five light-emitting diode (LED) light treatments were Control (no blue addition), 1B 06-08 (Blue light at 45 μmol m(-2) s(-1) from 06:00 to 08:00), 1B 21-08 (Blue light at 45 μmol m(-2) s(-1) from 21:00 to 08:00), 2B 17-19 (Blue at 80 μmol m(-2) s(-1) from 17:00 to 19:00), and 1B 17-19 (Blue at 45 μmol m(-2) s(-1) from 17:00 to 19:00). Total fresh and dry weight was not affected with additional blue light; however, plants treated with additional blue light were more compact. The stomatal conductance in the green lettuce cultivar was higher for all treatments with blue light compared to the Control. Photosynthetic yields measured with chlorophyll fluorescence showed different response between the cultivars; in red lettuce, the quantum yield of PSII decreased and the yield of non-photochemical quenching increased with increasing blue light, whereas in green lettuce no difference was observed. Quantification of secondary metabolites showed that all four treatments with additional blue light had higher amount of pigments, phenolic acids, and flavonoids compared to the Control. The effect was more prominent in red lettuce, highlighting that the results vary among treatments and compounds. Our results indicate that not only high light level triggers photoprotective heat dissipation in the plant, but also the specific spectral composition of the light itself at low intensities. However, these plant responses to light are cultivar dependent.

  8. Effect of Different Light Intensities on Total Phenolics and Flavonoids Synthesis and Anti-oxidant Activities in Young Ginger Varieties (Zingiber officinale Roscoe)

    Science.gov (United States)

    Ghasemzadeh, Ali; Jaafar, Hawa Z. E.; Rahmat, Asmah; Wahab, Puteri Edaroyati Megat; Halim, Mohd Ridzwan Abd

    2010-01-01

    Nowadays, phytochemicals and antioxidants in plants are raising interest in consumers for their roles in the maintenance of human health. Phenolics and flavonoids are known for their health-promoting properties due to protective effects against cardiovascular disease, cancers and other disease. Ginger (Zingiber officinale) is one of the traditional folk medicinal plants and it is widely used in cooking in Malaysia. In this study, four levels of glasshouse light intensities (310, 460, 630 and 790 μmol m−2s−1) were used in order to consider the effect of light intensity on the production, accumulation and partitioning of total phenolics (TP), total flavonoids (TF) and antioxidant activities in two varieties of Malaysian young ginger (Zingiber officinale). TF biosynthesis was highest in the Halia Bara variety under 310 μmol m−2s−1 and TP was high in this variety under a light intensity of 790 μmol m−2s−1. The highest amount of these components accumulated in the leaves and after that in the rhizomes. Also, antioxidant activities determined by the 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) assay in both of varieties, increased significantly (p ≤ 0.01) with increasing TF concentration, and high antioxidant activity was observed in the leaves of Halia Bara grown under 310 μmol m−2s−1. The ferric reducing (FRAP) activity of the rhizomes was higher than that of the leaves in 310 μmol m−2s−1 of sun light. This study indicates the ability of different light intensities to enhance the medicinal components and antioxidant activities of the leaves and young rhizomes of Zingiber officinale varieties. Additionally, this study also validated their medicinal potential based on TF and TP contents. PMID:21152306

  9. Effect of Different Light Intensities on Total Phenolics and Flavonoids Synthesis and Anti-oxidant Activities in Young Ginger Varieties (Zingiber officinale Roscoe

    Directory of Open Access Journals (Sweden)

    Ali Ghasemzadeh

    2010-10-01

    Full Text Available Nowadays, phytochemicals and antioxidants in plants are raising interest in consumers for their roles in the maintenance of human health. Phenolics and flavonoids are known for their health-promoting properties due to protective effects against cardiovascular disease, cancers and other disease. Ginger (Zingiber officinale is one of the traditional folk medicinal plants and it is widely used in cooking in Malaysia. In this study, four levels of glasshouse light intensities (310, 460, 630 and 790 μmol m−2s−1 were used in order to consider the effect of light intensity on the production, accumulation and partitioning of total phenolics (TP, total flavonoids (TF and antioxidant activities in two varieties of Malaysian young ginger (Zingiber officinale. TF biosynthesis was highest in the Halia Bara variety under 310 μmol m−2s−1 and TP was high in this variety under a light intensity of 790 μmol m−2s−1. The highest amount of these components accumulated in the leaves and after that in the rhizomes. Also, antioxidant activities determined by the 1,1-Diphenyl-2-picryl-hydrazyl (DPPH assay in both of varieties, increased significantly (p ≤ 0.01 with increasing TF concentration, and high antioxidant activity was observed in the leaves of Halia Bara grown under 310 μmol m−2s−1. The ferric reducing (FRAP activity of the rhizomes was higher than that of the leaves in 310 μmol m−2s−1 of sun light. This study indicates the ability of different light intensities to enhance the medicinal components and antioxidant activities of the leaves and young rhizomes of Zingiber officinale varieties. Additionally, this study also validated their medicinal potential based on TF and TP contents.

  10. Evaluating the influence of light intensity in mcyA gene expression and microcystin production in toxic strains of Planktothrix agardhii and Microcystis aeruginosa.

    Science.gov (United States)

    Salvador, Daniel; Churro, Catarina; Valério, Elisabete

    2016-04-01

    Cyanobacteria are phytoplanktonic organisms widely occurring in freshwaters, being frequently associated with the production of toxins, namely microcystins (MCs). MCs are produced non-ribosomally by a multienzyme complex (mcy genes). It has been reported that environmental factors, such as light intensity, can influence toxin production. The aim of this study was to assess the influence of light intensity in the transcription of the mcyA gene and corresponding production of microcystins in toxic isolates of Planktothrix agardhii, where little is known, and compare them to Microcystis aeruginosa. For that purpose, cultures were exposed to three different light intensities (4, 20 and 30 μmol photons m(-2) s(-1)) for 18 days at 20 ± 1 °C. The growth was followed daily using absorbance readings. Samples were collected at each growth stage for cell counting, microcystins quantification and RNA extraction. The level of transcripts was quantified by RT-qPCR and the relative expression determined using 16S rDNA, gltA and rpoC1 as reference genes. The most stable reference genes in M. aeruginosa were rpoC1 and gltA, whereas in P. agardhii were 16S rDNA and gltA. There was a correspondence between the growth rate and light intensity in M. aeruginosa and P. agardhii. The growth rates for both species were lower at 4 and higher at 30 μmol photons m(-2) s(-1). Microcystin concentration per cell was similar between light intensities in M. aeruginosa and over time, while in P. agardhii it was higher in the stationary phase at 4 μmol photons m(-2) s(-1). There were differences in the expression of mcyA between the two species. In M. aeruginosa, the highest levels of expression occurred at 4 μmol photons m(-2) s(-1) in the adaptation phase, whereas for P. agardhii it was at 4μmol photons m(-2) s(-1) in the exponential growth phase. Our results indicate that the light intensities tested had distinct influences on the growth, microcystin production and mcyA expression levels

  11. Light acclimation maintains the redox state of the PS II electron acceptor Q(A) within a narrow range over a broad range of light intensities.

    Science.gov (United States)

    Rosenqvist, E

    2001-01-01

    Chrysanthemum inducum-hybrid 'Coral Charm', Hibiscus rosa-sinensis L. 'Cairo Red' and Spathiphyllum wallisii Regel 'Petit' were grown in natural light in a greenhouse at three levels of irradiance using permanent shade screens. Light acclimation of photosynthesis was characterized using modulated chlorophyll a fluorescence of intact leaves. A close correlation was found between the degree of reduction of the primary electron acceptor Q(A) of Photosystem II (PS II) approximated as the fluorescence parameter 1-q(P), and light acclimation. The action range of 1-q(P) was 0-0.4 from darkness to full irradiance around noon, within the respective light treatments in the greenhouse, indicating that most PS II reaction centres were kept open. In general, the index for electron transport (ETR) measured by chlorophyll fluorescence was higher for high-light (HL) than intermediate-(IL) and low-light (LL) grown plants. However, HL Chrysanthemum showed 40% higher ETR than HL Hibiscus at light saturation, despite identical redox states of Q(A). The light acclimation of the non-radiative dissipation of excess energy in the antenna, NPQ, varied considerably between the species. However, when normalized against q(P), a strong negative correlation was found between thermal dissipation and ETR measured by chlorophyll fluorescence. To be able to accommodate a high flux of electrons through PS II, the plants with the highest light-saturated ETR had the lowest NPQ/q(P). The possibility of using chlorophyll fluorescence for quantification of the energy balance between energy input and utilization in PS II in intact leaves is discussed.

  12. HYDROGEN PRODUCTION BY THE CYANOBACTERIUM PLECTONEMA BORYANUM: EFFECTS OF INITIAL NITRATE CONCENTRATION, LIGHT INTENSITY, AND INHIBITION OF PHOTOSYSTEM II BY DCMU

    Energy Technology Data Exchange (ETDEWEB)

    Carter, B.; Huesemann, M.

    2008-01-01

    The alarming rate at which atmospheric carbon dioxide levels are increasing due to the burning of fossil fuels will have incalculable consequences if disregarded. Fuel cells, a source of energy that does not add to carbon dioxide emissions, have become an important topic of study. Although signifi cant advances have been made related to fuel cells, the problem of cheap and renewable hydrogen production still remains. The cyanobacterium Plectonema boryanum has demonstrated potential as a resolution to this problem by producing hydrogen under nitrogen defi cient growing conditions. Plectonema boryanum cultures were tested in a series of experiments to determine the effects of light intensity, initial nitrate concentration, and photosystem II inhibitor DCMU (3-(3,4- dichlorophenyl)-1,1-dimethylurea) upon hydrogen production. Cultures were grown in sterile Chu. No. 10 medium within photobioreactors constantly illuminated by halogen lights. Because the enzyme responsible for hydrogen production is sensitive to oxygen, the medium was continuously sparged with argon/CO2 (99.7%/0.3% vol/vol) by gas dispersion tubes immersed in the culture. Hydrogen production was monitored by using a gas chromatograph equipped with a thermal conductivity detector. In the initial experiment, the effects of initial nitrate concentration were tested and results revealed cumulative hydrogen production was maximum at an initial nitrate concentration of 1 mM. A second experiment was then conducted at an initial nitrate concentration of 1 mM to determine the effects of light intensity at 50, 100, and 200 μmole m-2 s-1. Cumulative hydrogen production increased with increasing light intensity. A fi nal experiment, conducted at an initial nitrate concentration of 2 mM, tested the effects of high light intensity at 200 and 400 μmole m-2 s-1. Excessive light at 400 μmole m-2 s-1 decreased cumulative hydrogen production. Based upon all experiments, cumulative hydrogen production rates were optimal

  13. Effects of light sources and intensity on broilers grown to heavy weights. Part 1: Growth performance, carcass characteristics, and welfare indices.

    Science.gov (United States)

    Olanrewaju, H A; Miller, W W; Maslin, W R; Collier, S D; Purswell, J L; Branton, S L

    2016-04-01

    This study investigated the effects of light sources and light intensity on growth performance, carcass characteristics, and welfare indices of heavy broilers (>3.0 kg) in 4 trials with 2 replications per trial. A total of 960 one-day-old Ross×Ross 708 chicks (30 males/30 females/room) were randomly distributed into 16 environmentally controlled rooms at 50% RH. A 4×2 factorial treatment structure evaluated 4 light sources (incandescent [ICD, standard], compact fluorescent [CFL], neutral light emitting diode [Neutral-LED], and cool poultry specific filtered LED [Cool-PSF-LED]) and 2 levels (5 lx, 20 lx) of light intensities. Each of the 4 light sources was paired with one of the 2 light intensities. Birds were fed the same diet with a 4-phase feeding program (starter, grower, finisher, and withdrawal). Feed and water were provided ad libitum. Birds and feed were weighed on one, 14, 21, 28, 42, and 56 d of age for growth performance. All mortality was recorded daily and feed conversion was adjusted for mortality. Immune response was determined on d 28 to d 35, whereas other welfare indices were performed on d 42 and 49, respectively. At d 56 of each trial, 20 (10 males and 10 females) birds from each room were processed to determine weights and yields. The BW, BW gain, live weight, and carcass weights of birds reared under Cool-PSF-LED were different (P≤0.05) in comparison to birds reared under ICD. However, FI, FCR, and mortality were not affected by treatments. There was no effect of treatments on fat or breast and tender weights and yields. In addition, there was no effect of treatments on ocular development, immune response, and other welfare indices, suggesting that the light sources evaluated did not compromise welfare of heavy broilers. It was concluded that the 3 light sources evaluated in this study may be suitable for replacement of ICD light source in poultry facilities to reduce energy cost and optimize production efficiency.

  14. The two-loop sunrise integral around four space-time dimensions and generalisations of the Clausen and Glaisher functions towards the elliptic case

    Science.gov (United States)

    Adams, Luise; Bogner, Christian; Weinzierl, Stefan

    2015-07-01

    We present the result for the finite part of the two-loop sunrise integral with unequal masses in four space-time dimensions in terms of the O ( ɛ0) -part and the O ( ɛ1) -part of the sunrise integral around two space-time dimensions. The latter two integrals are given in terms of elliptic generalisations of Clausen and Glaisher functions. Interesting aspects of the result for the O ( ɛ1 ) -part of the sunrise integral around two space-time dimensions are the occurrence of depth two elliptic objects and the weights of the individual terms.

  15. The two-loop sunrise integral around four space-time dimensions and generalisations of the Clausen and Glaisher functions towards the elliptic case

    CERN Document Server

    Adams, Luise; Weinzierl, Stefan

    2015-01-01

    We present the result for the finite part of the two-loop sunrise integral with unequal masses in four space-time dimensions in terms of the ${\\mathcal O}(\\varepsilon^0)$-part and the ${\\mathcal O}(\\varepsilon^1)$-part of the sunrise integral around two space-time dimensions. The latter two integrals are given in terms of elliptic generalisations of Clausen and Glaisher functions. Interesting aspects of the result for the ${\\mathcal O}(\\varepsilon^1)$-part of the sunrise integral around two space-time dimensions are the occurrence of depth two elliptic objects and the weights of the individual terms.

  16. Effects of light intensity on the distribution of anthocyanins in Kalanchoe brasiliensis Camb. and Kalanchoe pinnata (Lamk. Pers

    Directory of Open Access Journals (Sweden)

    Bruna P. Cruz

    2012-03-01

    Full Text Available This paper compares two medicinal species of Kalanchoe, which are often used interchangeably by the population, regarding the distribution of anthocyanins under the influence of four luminosity levels for 6 months. For the morphoanatomical analysis, the 6th stem node of each plant was sectioned. Usual histochemical tests revealed the presence of anthocyanins by cross sections of the stems, petioles and leaf blades. The petioles and leaf blades were submitted to the extraction with acidified methanol, and the anthocyanins were quantified by spectrophotometric readings. At the macroscopic level, it was noticed for both species a higher presence of anthocyanins in stems and petioles of plants under full sunlight. The microscopy of K. brasiliensis stems evidenced the deposition of anthocyanins in the subjacent tissue to the epidermis and cortex, which increased with light intensity. In K. pinnata a subepidermal collenchyma was observed, which interfered in the visualization of anthocyanins. In petioles and leaf blades of K. brasiliensis the deposition of anthocyanins was peripheral, and in K. pinnata it was also throughout the cortex. The quantification of anthocyanins in petioles showed in 70% of light higher averages than in 25%, but in leaf blades there were no significant results. This study contributes to the pharmacognosy of Kalanchoe and it is sustained by the description of flavonoids as biological markers of the genus.Este trabalho compara duas espécies medicinais de Kalanchoe utilizadas muitas vezes de forma indiferenciada pela população, quanto à distribuição de antocianinas sob influência de quatro níveis de luminosidade por 6 meses. Para a análise morfoanatômica foi seccionado o 6 º nó do caule de cada planta. Testes histoquímicos clássicos evidenciaram a presença de antocianinas em cortes transversais dos caules, pecíolos e lâminas foliares. Os pecíolos e lâminas foliares foram submetidos à extração com metanol

  17. Correlation between intensity fluctuations of light generated by scattering of Young’s diffractive electromagnetic waves by a quasi-homogeneous, anisotropic medium

    Science.gov (United States)

    Li, Jia; Chen, Feinan

    2016-11-01

    Based on the first-order Born approximation, formulas are derived for the correlation between intensity fluctuations (CIF) of light generated by a Young’s diffractive electromagnetic wave scattered by a spatially quasi-homogeneous (QH), anisotropic medium. It is shown that the CIF of the scattered field can be written as the summation of the Fourier transforms of the strengths and normalized correlation coefficients (NCCs) of the scattering potentials. The differences between our results and those obtained in the previous literature are discussed. Our results might be important in investigating the high-order intensity correlation of an electromagnetic wave scattered from a 3D anisotropic object.

  18. Climate sensitivity of gaseous elemental mercury dry deposition to plants: impacts of temperature, light intensity, and plant species.

    Science.gov (United States)

    Rutter, Andrew P; Schauer, James J; Shafer, Martin M; Creswell, Joel; Olson, Michael R; Clary, Alois; Robinson, Michael; Parman, Andrew M; Katzman, Tanya L

    2011-01-15

    Foliar accumulations of gaseous elemental mercury (GEM) were measured in three plant species between nominal temperatures of 10 and 30 °C and nominal irradiances of 0, 80, and 170 W m(-2) (300 nm-700 nm) in a 19 m(3) controlled environment chamber. The plants exposed were as follows: White Ash (Fraxinus americana; WA); White Spruce (Picea glauca; WS); and Kentucky Bluegrass (Poa partensis; KYBG). Foliar enrichments in the mercury stable isotope ((198)Hg) were used to measure mercury accumulation. Exposures lasted for 1 day after which the leaves were digested in hot acid and the extracted mercury was analyzed with ICPMS. Resistances to accumulative uptake by leaves were observed to be dependent on both light and temperature, reaching minima at optimal growing conditions (20 °C; 170 W m(-2) irradiance between 300-700 nm). Resistances typically increased at lower (10 °C) and higher (30 °C) temperatures and decreased with higher intensities of irradiance. Published models were modified and used to interpret the trends in stomatal and leaf interior resistances to GEM observed in WA. The model captured the experimental trends well and revealed that stomatal and internal resistances were both important across much of the temperature range. At high temperatures, however, stomatal resistance dominated due to increased water vapor pressure deficits. The resistances measured in this study were used to model foliar accumulations of GEM at a northern US deciduous forest using atmospheric mercury and climate measurements made over the 2003 growing season. The results were compared to modeled accumulations for GEM, RGM, and PHg using published deposition velocities. Predictions of foliar GEM accumulation were observed to be a factor of 5-10 lower when the temperature and irradiance dependent resistances determined in this study were used in place of previously published data. GEM uptake by leaves over the growing season was shown to be an important deposition pathway (2

  19. 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

  20. Measurement of Verdet constants with light intensity equipment%用光强分布测试仪测量费尔德常数

    Institute of Scientific and Technical Information of China (English)

    段江峰; 王晓坤; 刘竹琴

    2012-01-01

    利用激光,利用光强分布测试仪测量光强,采用数字检流计采集数据,并通过马吕斯定律计算出磁致旋光度,从而求出费尔德常数,并测量了水的费尔德常数.实验具有精度高、操作简单等优点.%This paper uses light intensity equipment to survey light intensity, the digital galvanometer to gather data, calculates the optical rotation through the Malus' law, and thus obtains specific rotation and concentration of the sucrose solution. It has the advantages of easy operation and precision and so on.