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Sample records for dexal light ja

  1. Lighting.

    SciTech Connect

    United States. Bonneville Power Administration.

    1992-09-01

    Since lighting accounts for about one-third of the energy used in commercial buildings, there is opportunity to conserve. There are two ways to reduce lighting energy use: modify lighting systems so that they used less electricity and/or reduce the number of hours the lights are used. This booklet presents a number of ways to do both. Topics covered include: reassessing lighting levels, reducing lighting levels, increasing bulb & fixture efficiency, using controls to regulate lighting, and taking advantage of daylight.

  2. Light

    NASA Astrophysics Data System (ADS)

    Vernon, C. G.

    2016-09-01

    Preface; 1. Historical; 2. Waves and wave-motion; 3. The behaviour of ripples; 4. The behaviour of light; 5. Refraction through glass blocks and prisms; 6. The imprinting of curvatures; 7. Simple mathematical treatment; 8. More advanced mathematical treatment; 9. The velocity of light; 10. The spectrum and colour; 11. Geometrical optics; 12. The eye and optical instruments; 13. Sources of light; 14. Interference, diffraction and polarisation; 15. Suggestions for class experiments; Index.

  3. Lighting

    SciTech Connect

    Audin, L.

    1994-12-31

    EPAct covers a vast territory beyond lighting and, like all legislation, also contains numerous {open_quotes}favors,{close_quotes} compromises, and even some sleight-of-hand. Tucked away under Title XIX, for example, is an increase from 20% to 28% tax on gambling winnings, effective January 1, 1993 - apparently as a way to help pay for new spending listed elsewhere in the bill. Overall, it is a landmark piece of legislation, about a decade overdue. It remains to be seen how the Federal Government will enforce upgrading of state (or even their own) energy codes. There is no mention of funding for {open_quotes}energy police{close_quotes} in EPAct. Merely creating such a national standard, however, provides a target for those who sincerely wish to create an energy-efficient future.

  4. The University of Jaén Astronomical Observatory

    NASA Astrophysics Data System (ADS)

    Martí, Josep; Luque-Escamilla, Pedro L.; García-Hernández, María T.

    2017-01-01

    We present a description and instrumental characterization of the photometric equipment of the Astronomical Observatory of the University of Jaén. The observatory hosts a 41 cm automated telescope inside a 4 m dome located at the university main campus, in the outskirts of the city of Jaén (Spain). This facility is used for educational, outreach and occasional scientific research on bright stellar objects. Despite the observatory location in a light polluted urban area, its performance for differential photometry studies has proven to be very acceptable. The discovery of the Be star LS I +5979 as a peculiar eclipsing binary system is so far the most relevant achievement.

  5. Nanoporous Silicon Ignition of JA2 Propellant

    DTIC Science & Technology

    2014-06-01

    Nanoporous Silicon Ignition of JA2 Propellant Stephen L. Howard Weapons and Materials Research Directorate, ARL Wayne A. Churaman Sensors and... Nanoporous Silicon Ignition of JA2 Propellant by Stephen L. Howard, Wayne A. Churaman, and Luke J. Currano ARL-TR-6950 June 2014...2014 2. REPORT TYPE Final 3. DATES COVERED (From - To) June 2010 4. TITLE AND SUBTITLE Nanoporous Silicon Ignition of JA2 Propellant 5a

  6. Treatment Plan Adherence for Your Child With JA

    MedlinePlus

    ... Juvenile Arthritis Camps Juvenile Arthritis Conference Resources JA Power Pack Educational Rights Kit JA Transition Toolkit Print ... Drevlow Family: Coping Through Community Tiffany Family Nora Powers: Taking Charge Jodi Van Emmerik: Happy Campers Bridget ...

  7. Effects of MeJA on Arabidopsis metabolome under endogenous JA deficiency

    NASA Astrophysics Data System (ADS)

    Cao, Jingjing; Li, Mengya; Chen, Jian; Liu, Pei; Li, Zhen

    2016-11-01

    Jasmonates (JAs) play important roles in plant growth, development and defense. Comprehensive metabolomics profiling of plants under JA treatment provides insights into the interaction and regulation network of plant hormones. Here we applied high resolution mass spectrometry based metabolomics approach on Arabidopsis wild type and JA synthesis deficiency mutant opr3. The effects of exogenous MeJA treatment on the metabolites of opr3 were investigated. More than 10000 ion signals were detected and more than 2000 signals showed significant variation in different genotypes and treatment groups. Multivariate statistic analyses (PCA and PLS-DA) were performed and a differential compound library containing 174 metabolites with high resolution precursor ion-product ions pairs was obtained. Classification and pathway analysis of 109 identified compounds in this library showed that glucosinolates and tryptophan metabolism, amino acids and small peptides metabolism, lipid metabolism, especially fatty acyls metabolism, were impacted by endogenous JA deficiency and exogenous MeJA treatment. These results were further verified by quantitative reverse transcription PCR (RT-qPCR) analysis of 21 related genes involved in the metabolism of glucosinolates, tryptophan and α-linolenic acid pathways. The results would greatly enhance our understanding of the biological functions of JA.

  8. Effects of MeJA on Arabidopsis metabolome under endogenous JA deficiency.

    PubMed

    Cao, Jingjing; Li, Mengya; Chen, Jian; Liu, Pei; Li, Zhen

    2016-11-24

    Jasmonates (JAs) play important roles in plant growth, development and defense. Comprehensive metabolomics profiling of plants under JA treatment provides insights into the interaction and regulation network of plant hormones. Here we applied high resolution mass spectrometry based metabolomics approach on Arabidopsis wild type and JA synthesis deficiency mutant opr3. The effects of exogenous MeJA treatment on the metabolites of opr3 were investigated. More than 10000 ion signals were detected and more than 2000 signals showed significant variation in different genotypes and treatment groups. Multivariate statistic analyses (PCA and PLS-DA) were performed and a differential compound library containing 174 metabolites with high resolution precursor ion-product ions pairs was obtained. Classification and pathway analysis of 109 identified compounds in this library showed that glucosinolates and tryptophan metabolism, amino acids and small peptides metabolism, lipid metabolism, especially fatty acyls metabolism, were impacted by endogenous JA deficiency and exogenous MeJA treatment. These results were further verified by quantitative reverse transcription PCR (RT-qPCR) analysis of 21 related genes involved in the metabolism of glucosinolates, tryptophan and α-linolenic acid pathways. The results would greatly enhance our understanding of the biological functions of JA.

  9. Effects of MeJA on Arabidopsis metabolome under endogenous JA deficiency

    PubMed Central

    Cao, Jingjing; Li, Mengya; Chen, Jian; Liu, Pei; Li, Zhen

    2016-01-01

    Jasmonates (JAs) play important roles in plant growth, development and defense. Comprehensive metabolomics profiling of plants under JA treatment provides insights into the interaction and regulation network of plant hormones. Here we applied high resolution mass spectrometry based metabolomics approach on Arabidopsis wild type and JA synthesis deficiency mutant opr3. The effects of exogenous MeJA treatment on the metabolites of opr3 were investigated. More than 10000 ion signals were detected and more than 2000 signals showed significant variation in different genotypes and treatment groups. Multivariate statistic analyses (PCA and PLS-DA) were performed and a differential compound library containing 174 metabolites with high resolution precursor ion-product ions pairs was obtained. Classification and pathway analysis of 109 identified compounds in this library showed that glucosinolates and tryptophan metabolism, amino acids and small peptides metabolism, lipid metabolism, especially fatty acyls metabolism, were impacted by endogenous JA deficiency and exogenous MeJA treatment. These results were further verified by quantitative reverse transcription PCR (RT-qPCR) analysis of 21 related genes involved in the metabolism of glucosinolates, tryptophan and α-linolenic acid pathways. The results would greatly enhance our understanding of the biological functions of JA. PMID:27883040

  10. Bili lights

    MedlinePlus

    Phototherapy for jaundice; Bilirubin - bili lights; Neonatal care - bili lights; Newborn care - bili lights ... Phototherapy involves shining fluorescent light from the bili lights on bare skin. A specific wavelength of light can break down bilirubin into a form that ...

  11. JA but not JA-Ile is the cell-nonautonomous signal activating JA mediated systemic defenses to herbivory in Nicotiana attenuata.

    PubMed

    Bozorov, Tohir A; Dinh, Son Truong; Baldwin, Ian T

    2017-08-01

    The whole-plant activation of defense responses to wounding and herbivory requires systemic signaling in which jasmonates (JAs) play a pivotal role. To examine the nature of the slower cell-nonautonomous as compared to the rapid cell-autonomous signal in mediating systemic defenses in Nicotiana attenuata, reciprocal stem grafting-experiments were used with plants silenced for the JA biosynthetic gene ALLENE OXIDE CYCLASE (irAOC) or plants transformed to create JA sinks by ectopically expressing Arabidopsis JA-O-methyltransferase (ovJMT). JA-impaired irAOC plants were defective in the cell-nonautonomous signaling pathway but not in JA transport. Conversely, ovJMT plants abrogated the production of a graft-transmissible JA signal. Both genotypes displayed unaltered cell-autonomous signaling. Defense responses (17-hydroxygeranyllinalool diterpene glycosides, nicotine, and proteinase inhibitors) and metabolite profiles were differently induced in irAOC and ovJMT scions in response to graft-transmissible signals from elicited wild type stocks. The performance of Manduca sexta larvae on the scions of different graft combinations was consistent with the patterns of systemic defense metabolite elicitations. Taken together, we conclude that JA and possibly MeJA, but not JA-Ile, either directly functions as a long-distance transmissible signal or indirectly interacts with long distance signal(s) to activate systemic defense responses. © 2017 Institute of Botany, Chinese Academy of Sciences.

  12. Lighting: Green Light.

    ERIC Educational Resources Information Center

    Maniccia, Dorine

    2003-01-01

    Explains that by using sustainable (green) building practices, schools and universities can make their lighting systems more efficient, noting that embracing green design principles can help schools attract students. Discusses lighting-control technologies (occupancy sensing technology, daylighting technology, and scheduling based technologies),…

  13. Lighting: Green Light.

    ERIC Educational Resources Information Center

    Maniccia, Dorine

    2003-01-01

    Explains that by using sustainable (green) building practices, schools and universities can make their lighting systems more efficient, noting that embracing green design principles can help schools attract students. Discusses lighting-control technologies (occupancy sensing technology, daylighting technology, and scheduling based technologies),…

  14. Transcriptome Analysis of Genes Associated with the Artemisinin Biosynthesis by Jasmonic Acid Treatment under the Light in Artemisia annua.

    PubMed

    Hao, Xiaolong; Zhong, Yijun; Fu, Xueqing; Lv, Zongyou; Shen, Qian; Yan, Tingxiang; Shi, Pu; Ma, Yanan; Chen, Minghui; Lv, Xueying; Wu, Zhangkuanyu; Zhao, Jingya; Sun, Xiaofen; Li, Ling; Tang, Kexuan

    2017-01-01

    Artemisinin is a sesquiterpene lactone endoperoxide extracted from a traditional Chinese medicinal plant Artemisia annua. Artemisinin-based combination therapies (ACTs) are recommended as the best treatment of malaria by the World Health Organization (WHO). Both the phytohormone jasmonic acid (JA) and light promote artemisinin biosynthesis in A. annua. Interestingly, we found that the increase of artemisinin biosynthesis by JA was dependent on light. However, the relationship between the two signal pathways mediated by JA and light remains unclear. Here, we collected the A. annua seedlings of 24 h continuous light (Light), 24 h dark treatment (Dark), 4 h MeJA treatment under the continuous light conditions (Light-MeJA-4h) and 4 h MeJA treatment under the dark conditions (Dark-MeJA-4h) and performed the transcriptome sequencing using Illumina HiSeq 4000 System. A total of 266.7 million clean data were produced and assembled into 185,653 unigenes, with an average length of 537 bp. Among them, 59,490 unigenes were annotated and classified based on the public information. Differential expression analyses were performed between Light and Dark, Light and Light-MeJA-4h, Dark and Dark-MeJA-4h, Light-MeJA-4h, and Dark-MeJA-4h, respectively. Furthermore, transcription factor (TF) analysis revealed that 1588 TFs were identified and divided into 55 TF families, with 284 TFs down-regulated in the Dark relative to Light and 96 TFs up-regulated in the Light-MeJA-4h relative to Light. 8 TFs were selected as candidates for regulating the artemisinin biosynthesis and one of them was validated to be involved in artemisinin transcriptional regulation by Dual-Luciferase (Dual-LUC) assay. The transcriptome data shown in our study offered a comprehensive transcriptional expression pattern influenced by the MeJA and light in A. annua seedling, which will serve as a valuable resource for further studies on transcriptional regulation mechanisms underlying artemisinin biosynthesis.

  15. Transcriptome Analysis of Genes Associated with the Artemisinin Biosynthesis by Jasmonic Acid Treatment under the Light in Artemisia annua

    PubMed Central

    Hao, Xiaolong; Zhong, Yijun; Fu, Xueqing; Lv, Zongyou; Shen, Qian; Yan, Tingxiang; Shi, Pu; Ma, Yanan; Chen, Minghui; Lv, Xueying; Wu, Zhangkuanyu; Zhao, Jingya; Sun, Xiaofen; Li, Ling; Tang, Kexuan

    2017-01-01

    Artemisinin is a sesquiterpene lactone endoperoxide extracted from a traditional Chinese medicinal plant Artemisia annua. Artemisinin-based combination therapies (ACTs) are recommended as the best treatment of malaria by the World Health Organization (WHO). Both the phytohormone jasmonic acid (JA) and light promote artemisinin biosynthesis in A. annua. Interestingly, we found that the increase of artemisinin biosynthesis by JA was dependent on light. However, the relationship between the two signal pathways mediated by JA and light remains unclear. Here, we collected the A. annua seedlings of 24 h continuous light (Light), 24 h dark treatment (Dark), 4 h MeJA treatment under the continuous light conditions (Light-MeJA-4h) and 4 h MeJA treatment under the dark conditions (Dark-MeJA-4h) and performed the transcriptome sequencing using Illumina HiSeq 4000 System. A total of 266.7 million clean data were produced and assembled into 185,653 unigenes, with an average length of 537 bp. Among them, 59,490 unigenes were annotated and classified based on the public information. Differential expression analyses were performed between Light and Dark, Light and Light-MeJA-4h, Dark and Dark-MeJA-4h, Light-MeJA-4h, and Dark-MeJA-4h, respectively. Furthermore, transcription factor (TF) analysis revealed that 1588 TFs were identified and divided into 55 TF families, with 284 TFs down-regulated in the Dark relative to Light and 96 TFs up-regulated in the Light-MeJA-4h relative to Light. 8 TFs were selected as candidates for regulating the artemisinin biosynthesis and one of them was validated to be involved in artemisinin transcriptional regulation by Dual-Luciferase (Dual-LUC) assay. The transcriptome data shown in our study offered a comprehensive transcriptional expression pattern influenced by the MeJA and light in A. annua seedling, which will serve as a valuable resource for further studies on transcriptional regulation mechanisms underlying artemisinin biosynthesis. PMID

  16. Effects of Light and Wounding on Jasmonates in Rice phyAphyC Mutants

    PubMed Central

    Brendel, Rita; Svyatyna, Katharina; Jikumaru, Yusuke; Reichelt, Michael; Mithöfer, Axel; Takano, Makoto; Kamiya, Yuji; Nick, Peter; Riemann, Michael

    2014-01-01

    Jasmonates (JA) are lipid-derived plant hormones. They have been shown to be important regulators of photomorphogenesis, a developmental program in plants, which is activated by light through different red and blue light sensitive photoreceptors. In rice, inhibition of coleoptile growth by light is a central event in photomorphogenesis. This growth inhibition is impaired, when jasmonate biosynthesis is knocked out. Previously, we found that JASMONATE RESISTANT 1 (OsJAR1) transcripts were not induced in the phytochrome (phy) mutant phyAphyC. Therefore, in the current study we investigated the regulation of JA and its highly bioactive derivative (+)-7-iso-jasmonoyl-l-isoleucine (JA-Ile), as well as the transcriptional regulation of several JA-dependent genes both in wild type and phyAphyC mutant. JA and JA-Ile levels increased in the mutant seedlings in response to blue light. However, in phyAphyC mutant leaves, which were continuously wounded, JA and JA-Ile levels were lower compared to those in the wild type. Hence, the mutation of phyA and phyC has differential effects on jasmonate levels depending on the tissue and developmental stage. Our results suggest that the contribution of JA-Ile to signaling during photomorphogenesis of rice is minor, as coleoptile phenotypes of phyAphyC mutants resemble those of jasmonate-deficient mutants despite the fact that induction by blue light leads to higher levels of JA-Ile compared to the wild type. We postulate that phyA and phyC could control the activity of specific enzymes metabolizing JA to active derivatives. PMID:27135497

  17. Combined elicitation of methyl-jasmonate and red light on stilbene and anthocyanin biosynthesis.

    PubMed

    Tassoni, Annalisa; Durante, Lorenzo; Ferri, Maura

    2012-05-15

    Vitis vinifera cell suspensions are a suitable system to study the metabolic regulation of a large range of polyphenols, including flavonoids and stilbenes that play important roles in plant development. Grape cv. Barbera petioles cell cultures were treated with red light and 10 μM methyl-jasmonate (MeJA), alone or in combination, to investigate their influence and/or induction effect on the production of anthocyanins, catechins and free and mono-glucosylated stilbenes. The synthesis of total anthocyanins was slightly decreased by red light alone, while MeJA and MeJA plus red light increased the levels of these metabolites. When compared to the relative controls, the red light treatment decreased the amount of catechins and increased their release in the culture medium, while MeJA alone or in combination with red light increased their production. Red light treatment generally enhanced the amount of free and mono-glucosylated stilbenes during the entire observation period, as well as the percentage of their release in the media. Treatment with MeJA strongly promoted the production of total stilbenes, which was further elicited by the MeJA plus red light treatment. During the combined treatment, the presence of the light stimulus improved the effect of MeJA by anticipating the maximum increase of stilbenes which were also largely released (up to 90%). These results demonstrate that, in grapevine, as in other plant systems, the change of conditions in which the MeJA stimulus is perceived (e.g. going from total white to red light) drastically modifies the plant response to this hormone. The present paper confirms that the jasmonate transduction pathway is integrated into an elaborate signaling network that also comprehends the red light signaling pathway. Copyright © 2012 Elsevier GmbH. All rights reserved.

  18. Continuous Dust Formation in SNe 2010jl and 2011ja

    NASA Astrophysics Data System (ADS)

    Krafton, Kelsie; Clayton, Geoffrey; Andrews, Jennifer; Barlow, Michael; De Looze, Ilse

    2016-08-01

    Studies in the last 10 years of dust formation in core-collapse supernovae (CCSNe) have found only small amounts, ~0.001 solar masses. This is far less than the amount needed to account for the large masses of dust seen in some high redshift galaxies. However, the recent discovery of ~1 solar mass of cold dust in the ejecta of SN 1987A has has caused a complete re-evaluation of dust formation in CCSNe. It has been suggested that the CCSNe are continuously forming dust so that by the time they are about 25 years old they will have dust masses similar to SN 1987A. However, there is a wide time gap between the CCSNe that have been studied recently and SN 1987A. We plan to use the sensitivity of Spitzer to detect dust emission from CCSNe 5 or more years after explosion. Radiative transfer models will be used to estimate the dust masses. This proposal is to continue our study of two interesting SNe 2010jl and 2011ja. These observations are part of a long term study requiring multiple epochs of Spitzer observations to look for evidence of continuous dust formation. These observations will help shed light on the mystery of dust in SN 1987A.

  19. Structural basis of jasmonate-amido synthetase FIN219 in complex with glutathione S-transferase FIP1 during the JA signal regulation

    PubMed Central

    Chen, Chun-Yen; Ho, Sih-Syun; Kuo, Tzu-Yen; Cheng, Yi-Sheng

    2017-01-01

    Far-red (FR) light-coupled jasmonate (JA) signaling is necessary for plant defense and development. FR insensitive 219 (FIN219) is a member of the Gretchen Hagen 3 (GH3) family of proteins in Arabidopsis and belongs to the adenylate-forming family of enzymes. It directly controls biosynthesis of jasmonoyl-isoleucine in JA-mediated defense responses and interacts with FIN219-interacting protein 1 (FIP1) under FR light conditions. FIN219 and FIP1 are involved in FR light signaling and are regulators of the interplay between light and JA signaling. However, how their interactions affect plant physiological functions remains unclear. Here, we demonstrate the crystal structures of FIN219–FIP1 while binding with substrates at atomic resolution. Our results show an unexpected FIN219 conformation and demonstrate various differences between this protein and other members of the GH3 family. We show that the rotated C-terminal domain of FIN219 alters ATP binding and the core structure of the active site. We further demonstrate that this unique FIN219–FIP1 structure is crucial for increasing FIN219 activity and determines the priority of substrate binding. We suggest that the increased FIN219 activity resulting from the complex form, a conformation for domain switching, allows FIN219 to switch to its high-affinity mode and thereby enhances JA signaling under continuous FR light conditions. PMID:28223489

  20. Endogenous Bioactive Jasmonate Is Composed of a Set of (+)-7-iso-JA-Amino Acid Conjugates.

    PubMed

    Yan, Jianbin; Li, Suhua; Gu, Min; Yao, Ruifeng; Li, Yuwen; Chen, Juan; Yang, Mai; Tong, Jianhua; Xiao, Langtao; Nan, Fajun; Xie, Daoxin

    2016-12-01

    Jasmonates (JAs) regulate a wide range of plant defense and development processes. The bioactive JA is perceived by its receptor COI1 to trigger the degradation of JASMONATE ZIM-DOMAIN (JAZ) proteins and subsequently derepress the JAZ-repressed transcription factors for activation of expression of JA-responsive genes. So far, (+)-7-iso-JA-l-Ile has been the only identified endogenous bioactive JA molecule. Here, we designed coronafacic acid (CFA) conjugates with all the amino acids (CFA-AA) to mimic the JA amino acid conjugates, and revealed that (+)-7-iso-JA-Leu, (+)-7-iso-JA-Val, (+)-7-iso-JA-Met, and (+)-7-iso-JA-Ala are new endogenous bioactive JA molecules. Furthermore, our studies uncover the general characteristics for all the bioactive JA molecules, and provide a new strategy to synthetically generate novel active JA molecules.

  1. Light Pollution

    ERIC Educational Resources Information Center

    Riegel, Kurt W.

    1973-01-01

    Outdoor lighting is light pollution which handicaps certain astronomical programs. Protective measures must be adopted by the government to aid observational astronomy without sacrificing legitimate outdoor lighting needs. (PS)

  2. Light Duty.

    ERIC Educational Resources Information Center

    Rogers, Jeff

    1996-01-01

    Discusses multipurpose athletic-field lighting specifications to enhance lighting quality and reduce costs. Topics discussed include lamp choice, lighting spillover and glare prevention, luminary assemblies and poles, and the electrical dimming and switching systems. (GR)

  3. Light Pollution

    ERIC Educational Resources Information Center

    Riegel, Kurt W.

    1973-01-01

    Outdoor lighting is light pollution which handicaps certain astronomical programs. Protective measures must be adopted by the government to aid observational astronomy without sacrificing legitimate outdoor lighting needs. (PS)

  4. Light Duty.

    ERIC Educational Resources Information Center

    Rogers, Jeff

    1996-01-01

    Discusses multipurpose athletic-field lighting specifications to enhance lighting quality and reduce costs. Topics discussed include lamp choice, lighting spillover and glare prevention, luminary assemblies and poles, and the electrical dimming and switching systems. (GR)

  5. Far-Red Light-Mediated Seedling Development in Arabidopsis Involves FAR-RED INSENSITIVE 219/JASMONATE RESISTANT 1-Dependent and -Independent Pathways

    PubMed Central

    Chen, Huai-Ju; Chen, Cheng-Ling; Hsieh, Hsu-Liang

    2015-01-01

    Plant growth and development is often regulated by the interaction of environmental factors such as light and various phytohormones. Arabidopsis FAR-RED INSENSITIVE 219 (FIN219)/JASMONATE RESISTANT 1 (JAR1) participates in phytochrome A-mediated far-red (FR) light signaling and interacts with different light signaling regulators. FIN219/JAR1 is a jasmonic acid (JA)-conjugating enzyme responsible for the formation of JA-isoleucine. However, how FIN219/JAR1 integrates FR light and JA signaling remains largely unknown. We used a microarray approach to dissect the effect of fin219 mutation on the interaction of FR light and JA signaling. The fin219-2 mutant was less sensitive than the wild type to various concentrations of methyl jasmonate (MeJA) under low and high FR light. High FR light reduced the sensitivity of Arabidopsis seedlings to MeJA likely through FIN219. Intriguingly, in response to MeJA, FIN219 levels showed a negative feedback regulation. Further microarray assay revealed that FR light could regulate gene expression by FIN219-dependent or -independent pathways. The expression profiles affected in fin219-2 indicated that FIN219/JAR1 plays a critical role in the integration of multiple hormone-related signaling. In particular, FIN219 regulates a number of transcription factors (TFs), including 94 basic helix-loop-helix (bHLH) TFs, in response to FR light and MeJA. Loss-of-function mutants of some bHLH TFs affected by FIN219 showed altered responses to MeJA in the regulation of hypocotyl and root elongation. Thus, FIN219/JAR1 is tightly regulated in response to exogenous MeJA. It also interacts with multiple plant hormones to modulate hypocotyl and root elongation of Arabidopsis seedlings likely by regulating a group of TFs. PMID:26176841

  6. Lighting Conservation

    ERIC Educational Resources Information Center

    Arnold, Frank D.

    1975-01-01

    With the energy crisis has come an awareness of wasteful consumption practices. One area where research is being done is in lighting conservation. Information in this article is concerned with finding more effective and efficient lighting designs which include daylight utilization, task-oriented lighting, and lighting controls. (MA)

  7. Regulation of extrafloral nectar secretion by jasmonates in lima bean is light dependent

    PubMed Central

    Radhika, Venkatesan; Kost, Christian; Mithöfer, Axel; Boland, Wilhelm

    2010-01-01

    To maximize fitness, plants need to perceive changes in their light environment and adjust their physiological responses accordingly. Whether and how such changes also affect the regulation of their defense responses against herbivores remains largely unclear. We addressed this issue by studying the secretion of extrafloral nectar (EFN) in lima bean (Phaseolus lunatus), which is known to be activated by the phytohormone jasmonic acid (JA) and functions as an indirect defense mechanism against herbivores. We found that the plant’s EFN secretion in response to JA was light dependent: In the dark, JA reduced EFN secretion, whereas under light conditions, JA induced EFN secretion relative to controls. This modulation was affected by the light’s spectral composition [i.e., ratio of red to far-red (R:FR) radiation], but not light intensity. These findings demonstrate a unique differential effect of JA on EFN secretion depending on the ambient light conditions. Interestingly, treatment with the isoleucine–JA conjugate (JA–Ile) enhanced EFN secretion under light conditions yet did not reduce EFN secretion in the dark. Moreover, inhibition of Ile biosynthesis in light-exposed plants significantly decreased the EFN secretion rate. This reduction could be recovered by additional application of JA–Ile, suggesting that JA–Ile is the active compound required to up-regulate EFN secretion. Finally, experiments with mechanically damaged plants revealed that light was required for the formation of JA–Ile, but not of JA. These results demonstrate that in lima bean, the light environment modulates the plant’s response to jasmonates as well as JA–Ile biosynthesis, which controls the subsequent EFN secretion. PMID:20855624

  8. Coordinate expression of AOS genes and JA accumulation: JA is not required for initiation of closing layer in wound healing tubers.

    PubMed

    Lulai, Edward; Huckle, Linda; Neubauer, Jonathan; Suttle, Jeffrey

    2011-06-15

    Wounding induces a series of coordinated physiological responses essential for protection and healing of the damaged tissue. Wound-induced formation of jasmonic acid (JA) is important in defense responses in leaves, but comparatively little is known about the induction of JA biosynthesis and its role(s) in tuber wound-healing. In this study, the effects of wounding on JA content, expression of JA biosynthetic genes, and the involvement of JA in the initiation of closing layer formation in potato tubers were determined. In addition, the role of abscisic acid (ABA) in wound-induced JA accumulation was examined. The basal JA content in non-wounded tuber tissues was low (< 3 ng g⁻¹ FW). Two hours after wounding, the JA content increased by > 5-fold, reached a maximum between 4 and 6h after wounding, and declined to near-basal levels thereafter. Tuber age (storage duration) had little effect on the pattern of JA accumulation. The expressions of the JA biosynthetic genes (StAOS2, StAOC, and StOPR3) were greatly increased by wounding reaching a maximum 2-4 h after wounding and declining thereafter. A 1-h aqueous wash of tuber discs immediately after wounding resulted in a 94% inhibition of wound-induced JA accumulation. Neither JA treatment nor inhibition of JA accumulation affected suberin polyphenolic accumulation during closing layer development indicating that JA was not essential for the initiation of primary suberization. ABA treatment did not restore JA accumulation in washed tuber tissues suggesting that leaching of endogenous ABA was either not involved or not solely involved in this loss of JA accumulation by washing. Collectively, these results indicate that JA is not required for the induction of processes essential to the initiation of suberization during closing layer development, but do not exclude the possibility that JA may be involved in other wound related responses. Published by Elsevier GmbH.

  9. RuBPCase activase mediates growth-defense tradeoffs: Silencing RCA redirects JA flux from JA-Ile to MeJA to attenuate induced defense responses in Nicotiana attenuata

    PubMed Central

    Mitra, Sirsha; Baldwin, Ian T.

    2014-01-01

    Summary RuBPCase activase (RCA), an abundant photosynthetic protein is strongly down-regulated in response to Manduca sexta’s oral secretion (OS) in Nicotiana attenuata. RCA-silenced plants are impaired not only in photosynthetic capacity and growth, but also in jasmonic acid (JA)-isoleucine (Ile) signaling, and herbivore resistance mediated by JA-Ile dependent defense traits. These responses are consistent with a resource-based growth-defense trade-off. Since JA+Ile-supplementation of OS restored WT levels of JA-Ile, defenses and resistance to M. sexta, but OS supplemented individually with JA- or Ile did not, the JA-Ile deficiency of RCA-silenced plants could not be attributed to lower JA or Ile pools or JAR4/6 conjugating activity. Similar levels of JA-Ile derivatives after OS elicitation indicated unaltered JA-Ile turnover and lower levels of other JA-conjugates ruled out competition from other conjugation reactions. RCA-silenced plants accumulated more methyl jasmonate (MeJA) after OS elicitation, which corresponded with increased jasmonate methyltransferase (JMT) activity. RCA-silencing phenocopies JMT over-expression, wherein elevated JMT activity redirects OS-elicited JA flux towards inactive MeJA, creating a JA sink which depletes JA-Ile and its associated defense responses. Hence RCA plays an additional non-photosynthetic role in attenuating JA-mediated defenses and their associated costs potentially allowing plants to anticipate resource-based constraints on growth before they actually occur. PMID:24491116

  10. Light Visor

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Seasonal Affective Disorder is a form of depression brought on by reduced light. For some people, this can lead to clinical depression. NASA has conducted research in light therapy and employs it to help astronauts adjust internal rhythms during orbital flight. Dr. George Brainard, a medical researcher and NASA consultant, has developed a portable light therapy device, which is commercially available. The Light Visor allows continuous light therapy and can be powered by either batteries or electricity. Dr. Brainard continues to research various aspects of light therapy.

  11. Light Motives.

    ERIC Educational Resources Information Center

    Filler, Martin

    1979-01-01

    The new energy consciousness has led to a thorough reevaluation of how artificial lighting can be used wisely, while other researchers have explored the potential of daylighting as an alternative interior light source. (Author/MLF)

  12. Light Reflector

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Ultra Sales, Inc.'s fluorescent lighting fixture gets a boost in reflectivity through installation of Lightdriver, a thin tough thermoplastic film plated with aluminum, capable of reflecting 95 percent of visible light striking it. Lightdriver increases brightness without adding bulbs, and allows energy savings by removing some bulbs because the mirrorlike surface cuts light loss generally occasioned by conventional low reflectivity white painted surface above the bulbs in many fluorescent fixtures. Forty-five percent reduction in lighting electricity is attainable.

  13. Lighting Utilization.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with lighting utilization. Its objective is for the student to be able to outline the development of lighting use and conservation and identify major types and operating characteristics of lamps used in electric lighting. Some topics…

  14. SCHOOL LIGHTING

    ERIC Educational Resources Information Center

    1965

    SEVERAL ARTICLES ON SCHOOL LIGHTING ARE CONTAINED IN THIS JOURNAL. THE TITLES AND AUTHORS INCLUDED ARE AS FOLLOWS--(1) "TODAY'S CONCEPTS IN SCHOOL LIGHTING" BY CHARLES D. GIBSON, (2) "CHALLENGE OF TOMMORROW'S LIGHTING" BY S.K. GUTH AND E.H. WITTE, (3) "PEEK PREVIEW OF THE WINDOWLESS SCHOOL" BY JAMES J. MORISSEAU, (4) "MAINTENANCE BEGINS BEFORE…

  15. SCHOOL LIGHTING

    ERIC Educational Resources Information Center

    1965

    SEVERAL ARTICLES ON SCHOOL LIGHTING ARE CONTAINED IN THIS JOURNAL. THE TITLES AND AUTHORS INCLUDED ARE AS FOLLOWS--(1) "TODAY'S CONCEPTS IN SCHOOL LIGHTING" BY CHARLES D. GIBSON, (2) "CHALLENGE OF TOMMORROW'S LIGHTING" BY S.K. GUTH AND E.H. WITTE, (3) "PEEK PREVIEW OF THE WINDOWLESS SCHOOL" BY JAMES J. MORISSEAU, (4) "MAINTENANCE BEGINS BEFORE…

  16. Light Source

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Research on food growth for long duration spacecraft has resulted in a light source for growing plants indoors known as Qbeam, a solid state light source consisting of a control unit and lamp. The light source, manufactured by Quantum Devices, Inc., is not very hot, although it generates high intensity radiation. When Ron Ignatius, an industrial partner of WCSAR, realized that terrestrial plant research lighting was not energy efficient enough for space use, he and WCSAR began to experiment with light emitting diodes. A line of LED products was developed, and QDI was formed to market the technology. An LED-based cancer treatment device is currently under development.

  17. Accumulation of anthocyanin and associated gene expression in radish sprouts exposed to light and methyl jasmonate.

    PubMed

    Park, Woo Tae; Kim, Yeon Bok; Seo, Jeong Min; Kim, Sun-Ju; Chung, Eunsook; Lee, Jai-Heon; Park, Sang Un

    2013-05-01

    Radish (Raphanus sativus) sprouts have received attention as an important dietary vegetable in Asian countries. The flavonoid pathway leading to anthocyanin biosynthesis in radishes is induced by multiple regulatory genes as well as various developmental and environmental factors. This study investigated anthocyanin accumulation and the transcript level of associated genes in radish sprouts exposed to light and methyl jasmonate (MeJA). The anthocyanin content of sprouts exposed to light and treated with MeJA was higher than that of sprouts grown under dark conditions without MeJA, and the highest anthocyanin content was observed within 6-9 days after sowing (DAS). Transcript levels of almost all genes were increased in radish sprouts grown in light conditions with 100 μM MeJA relative to sprouts grown under dark conditions with or without MeJA treatment, especially at 3 DAS. The results suggest that light and MeJA treatment applied together during radish seedling development enhance anthocyanin accumulation.

  18. Jasmonic acid enhancement of anthocyanin accumulation is dependent on phytochrome A signaling pathway under far-red light in Arabidopsis.

    PubMed

    Li, Ting; Jia, Kun-Peng; Lian, Hong-Li; Yang, Xu; Li, Ling; Yang, Hong-Quan

    2014-11-07

    Anthocyanins are critical for plants. It is shown that the expression of genes encoding the key enzymes such as dihydroflavonol 4-reductase (DFR), UDP-Glc: flavonoid 3-O-glucosyltransferase (UF3GT), and leucoanthocyanidin dioxygenase (LDOX) in anthocyanin biosynthesis pathway is regulated by MYB75, a R2R3 MYB transcription factor. The production of anthocyanin is known to be promoted by jasmonic acid (JA) in light but not in darkness. The photoreceptors cryptochrome 1 (CRY1), phytochrome B (phyB), and phytochrome A (phyA) are also shown to mediate light promotion of anthocyanin accumulation, respectively, whereas their downstream factor COP1, a master negative regulator of photomorphogensis, represses anthocyanin accumulation. However, whether JA coordinates with photoreceptors in the regulation of anthocyanin accumulation is unknown. Here, we show that under far-red light, JA promotes anthocyanin accumulation in a phyA signaling pathway-dependent manner. The phyA mutant is hyposensitive to jasmonic acid analog methyl jasmonic acid (MeJA) under far-red light. The dominant mutant of MYB75, pap1-D, accumulates significantly higher levels of anthocyanin than wild type under far-red light, whereas knockdown of MYBs (MYB75, MYB90, MYB113, and MYB114) through RNAi significantly reduces MeJA promotion of anthocyanin accumulation. The phyA pap1-D double mutant shows reduced responsiveness to MeJA, similar to phyA mutant under far-red light. In darkness, a mutant allele of cop1, cop1-4, shows enhanced responsiveness to MeJA, but pap1-D mutant is barely responsive to MeJA. Upon MeJA application, the cop1-4 pap1-D double mutant accumulates considerably higher levels of anthocyanin than cop1-4 in darkness. Protein studies indicate that MYB75 protein is stabilized by white light and far-red light. Further gene expression studies suggest that MeJA promotes the expression of DFR, UF3GT, and LDOX genes in a phyA- and MYB75-dependent manner under far-red light. Our findings suggest

  19. Lotus japonicus nodulation is photomorphogenetically controlled by sensing the red/far red (R/FR) ratio through jasmonic acid (JA) signaling

    PubMed Central

    Suzuki, Akihiro; Suriyagoda, Lalith; Shigeyama, Tamaki; Tominaga, Akiyoshi; Sasaki, Masayo; Hiratsuka, Yoshimi; Yoshinaga, Aya; Arima, Susumu; Agarie, Sakae; Sakai, Tatsuya; Inada, Sayaka; Jikumaru, Yusuke; Kamiya, Yuji; Uchiumi, Toshiki; Abe, Mikiko; Hashiguchi, Masatsugu; Akashi, Ryo; Sato, Shusei; Kaneko, Takakazu; Tabata, Satoshi; Hirsch, Ann M.

    2011-01-01

    Light is critical for supplying carbon to the energetically expensive, nitrogen-fixing symbiosis between legumes and rhizobia. Here, we show that phytochrome B (phyB) is part of the monitoring system to detect suboptimal light conditions, which normally suppress Lotus japonicus nodule development after Mesorhizobium loti inoculation. We found that the number of nodules produced by L. japonicus phyB mutants is significantly reduced compared with the number produced of WT Miyakojima MG20. To explore causes other than photoassimilate production, the possibility that local control by the root genotype occurred was investigated by grafting experiments. The results showed that the shoot and not the root genotype is responsible for root nodule formation. To explore systemic control mechanisms exclusive of photoassimilation, we moved WT MG20 plants from white light to conditions that differed in their ratios of low or high red/far red (R/FR) light. In low R/FR light, the number of MG20 root nodules dramatically decreased compared with plants grown in high R/FR, although photoassimilate content was higher for plants grown under low R/FR. Also, the expression of jasmonic acid (JA) -responsive genes decreased in both low R/FR light-grown WT and white light-grown phyB mutant plants, and it correlated with decreased jasmonoyl-isoleucine content in the phyB mutant. Moreover, both infection thread formation and root nodule formation were positively influenced by JA treatment of WT plants grown in low R/FR light and white light-grown phyB mutants. Together, these results indicate that root nodule formation is photomorphogenetically controlled by sensing the R/FR ratio through JA signaling. PMID:21930895

  20. WOW: light print, light propel, light point

    NASA Astrophysics Data System (ADS)

    Glückstad, Jesper; Bañas, Andrew; Aabo, Thomas; Palima, Darwin

    2012-10-01

    We are presenting so-called Wave-guided Optical Waveguides (WOWs) fabricated by two-photon polymerization and capable of being optically manipulated into any arbitrary orientation. By integrating optical waveguides into the structures we have created freestanding waveguides which can be positioned anywhere in a sample at any orientation using real-time 3D optical micromanipulation with six degrees of freedom. One of the key aspects of our demonstrated WOWs is the change in direction of in-coupled light and the marked increase in numerical aperture of the out-coupled light. Hence, each light propelled WOW can tap from a relatively broad incident beam and generate a much more tightly confined light at its tip. The presentation contains both numerical simulations related to the propagation of light through a WOW and preliminary experimental demonstrations on our BioPhotonics Workstation. In a broader context, this research shows that optically trapped micro-fabricated structures can potentially help bridge the diffraction barrier. This structure-mediated paradigm may be carried forward to open new possibilities for exploiting beams from far-field optics down to the sub-wavelength domain.

  1. Emergency Lighting

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A lighting system originally developed for NASA's Apollo and Skylab manned spacecraft resulted in a industrial spinoff and creation of a whole new company to produce and market the product line. The company is UDEC Corp., Waltham, Mass. UDEC's "Multi-Mode" electronic lighting systems are designed for plant emergency and supplemental use, such as night lighting, "always-on" stairwell lights and illuminated exit signs. Their advantages stem from the qualities demanded for spacecraft installation: extremely high fight output with very low energy drain, compactness, light weight, and high reliability. The Multi-Mode system includes long-life fluorescent lamps operated by electronic circuitry, a sealed battery that needs no maintenance for 10 years, and a solid-state battery charger. A typical emergency installation consists of a master module with battery and an eight watt lamp, together with four remote "Satellight" modules powered by the master's battery. As a night lighting system for maintenance or I security, UDEC fixtures can bypass the battery and 1 operate on normal current at a fraction of the energy 1 demand of conventional night lighting. Industrial customers have realized savings of better than ninety percent with UDEC night lights. UDEC started as a basement industry in 1972 but the company has already sold more than 1,000 lighting systems to building operators.

  2. EDITORIAL: Slow light Slow light

    NASA Astrophysics Data System (ADS)

    Boyd, Robert; Hess, Ortwin; Denz, Cornelia; Paspalakis, Emmanuel

    2010-10-01

    Research into slow light began theoretically in 1880 with the paper [1] of H A Lorentz, who is best known for his work on relativity and the speed of light. Experimental work started some 60 years later with the work of S L McCall and E L Hahn [2] who explored non-linear self-induced transparency in ruby. This field of research has burgeoned in the last 10 years, starting with the work of L Vestergaard Hau and coworkers on slow light via electromagnetically induced transparency in a Bose-Einstein condensate [3]. Many groups are now able to slow light down to a few metres per second or even stop the motion of light entirely [4]. Today, slow light - or more often `slow and fast light' - has become its own vibrant field with a strongly increasing number of publications. In broad scope, slow light research can be categorized in terms of the sort of physical mechanism used to slow down the light. One sort of slow light makes use of material dispersion. This dispersion can be the natural dispersion of the ordinary refractive index or can be the frequency dependence of some nonlinear optical process, such as electromagnetically induced transparency, coherent population oscillations, stimulated light scattering, or four-wave mixing processes. The second sort of slow light makes use of the wavelength dependence of artificially structured materials, such as photonic crystals, optical waveguides, and collections of microresonators. Material systems in which slow light has been observed include metal vapours, rare-earth-doped materials, Raman and Brillioun gain media, photonic crystals, microresonators and, more recently, metamaterials. A common feature of all of these schemes is the presence of a sharp single resonance or multiple resonances produced by an atomic transition, a resonance in a photonic structure, or in a nonlinear optical process. Current applications of slow light include a series of attractive topics in optical information processing, such as optical data

  3. Light Learning.

    ERIC Educational Resources Information Center

    Cutshall, Sandy

    2002-01-01

    Describes a career and technical education program on photonics, the study, research, and development of equipment and concepts used in the transmission of information through light, including fiber optics and experimental laser technologies. (JOW)

  4. Combination Light

    NASA Astrophysics Data System (ADS)

    1990-01-01

    The Rayovac TANDEM is an advanced technology combination work light and general purpose flashlight that incorporates several NASA technologies. The TANDEM functions as two lights in one. It features a long range spotlight and wide angle floodlight; simple one-hand electrical switching changes the beam from spot to flood. TANDEM developers made particular use of NASA's extensive research in ergonomics in the TANDEM's angled handle, convenient shape and different orientations. The shatterproof, water resistant plastic casing also draws on NASA technology, as does the shape and beam distance of the square diffused flood. TANDEM's heavy duty magnet that permits the light to be affixed to any metal object borrows from NASA research on rare earth magnets that combine strong magnetic capability with low cost. Developers used a NASA-developed ultrasonic welding technique in the light's interior.

  5. Light Learning.

    ERIC Educational Resources Information Center

    Cutshall, Sandy

    2002-01-01

    Describes a career and technical education program on photonics, the study, research, and development of equipment and concepts used in the transmission of information through light, including fiber optics and experimental laser technologies. (JOW)

  6. Circadian light

    PubMed Central

    2010-01-01

    The present paper reflects a work in progress toward a definition of circadian light, one that should be informed by the thoughtful, century-old evolution of our present definition of light as a stimulus for the human visual system. This work in progress is based upon the functional relationship between optical radiation and its effects on nocturnal melatonin suppression, in large part because the basic data are available in the literature. Discussed here are the fundamental differences between responses by the visual and circadian systems to optical radiation. Brief reviews of photometry, colorimetry, and brightness perception are presented as a foundation for the discussion of circadian light. Finally, circadian light (CLA) and circadian stimulus (CS) calculation procedures based on a published mathematical model of human circadian phototransduction are presented with an example. PMID:20377841

  7. Light's twist

    PubMed Central

    Padgett, Miles

    2014-01-01

    That light travels in straight lines is a statement of the obvious. However, the energy and momentum flow within light beams can twist to form vortices such as eddies in a stream. These twists carry angular momentum, which can make microscopic objects spin, be used to encode extra information in communication systems, enable the design of novel imaging systems and allow new tests of quantum mechanics. PMID:25484612

  8. Increased SA in NPR1-silenced plants antagonizes JA and JA-dependent direct and indirect defenses in herbivore-attacked Nicotiana attenuata in nature.

    PubMed

    Rayapuram, Cbgowda; Baldwin, Ian T

    2007-11-01

    The phytohormone jasmonic acid (JA) is known to mediate herbivore resistance, while salicylic acid (SA) and non-expressor of PR-1 (NPR1) mediate pathogen resistance in many plants. Herbivore attack on Nicotiana attenuata elicits increases in JA and JA-mediated defenses, but also increases SA levels and Na-NPR1 transcripts from the plant's single genomic copy. SA treatment of wild-type plants increases Na-NPR1 and Na-PR1 transcripts. Plants silenced in NPR1 accumulation by RNAi (ir-npr1) are highly susceptible to herbivore and pathogen attack when planted in their native habitat in Utah. They are also impaired in their ability to attract Geocorus pallens predators, due to their decreased ability to release cis-alpha-bergamotene, a JA-elicited volatile 'alarm call'. In the glasshouse, Spodoptera exigua larvae grew better on ir-npr1 plants, which had low levels of JA, JA-isoleucine/leucine, lipoxygenase-3 (LOX3) transcripts and JA-elicited direct defense metabolites (nicotine, caffeoyl putrescine and rutin), but high levels of SA and isochorismate synthase (ICS) transcripts, suggesting de novo biosynthesis of SA. A microarray analysis revealed downregulation of many JA-elicited genes and upregulation of SA biosynthetic genes. JA treatment restored nicotine levels and resistance to S. exigua in ir-npr1 plants. We conclude that, during herbivore attack, NPR1 negatively regulates SA production, allowing the unfettered elicitation of JA-mediated defenses; when NPR1 is silenced, the elicited increases in SA production antagonize JA and JA-related defenses, making the plants susceptible to herbivores.

  9. Synchrotron light

    SciTech Connect

    Craievich, A. )

    1990-01-01

    Several developed countries such as the USA, URSS, England, France, Italy, Sweden and Japan have one or more of these synchrotron light facilities operating or under construction. Some developing countries have constructed (China) or are building (Taiwan, India, Korea, Brazil) synchrotron light facilities. The construction of the Brazilian synchrotron source began in June, 1987. After two years of activities, the injector linac for the electron storage ring is in its final stage of construction. These Proceedings contain the Invited Lectures presented at the Workshop by specialists working on synchrotron light applications and related instrumentation and by members of LNLS regarding technical details of the Brazilian project. The II Workshop Synchrotron Light: Applications and Related Instrumentation was dedicated to oral presentations about applications of synchrotron light, most of which were not covered during the I Workshop, organized by LNLS in 1988, and the Proceedings of which were published by World Scientific. The II Workshop included discussions on the application possibilities for the newly designed LNLS 1.15 GeV storage ring, and on the modifications which would eventually be necessary for the work-station and instrumentation projects currently in progress at LNLS and at various external user laboratories.

  10. Light's Darkness

    ScienceCinema

    Padgett, Miles [University of Glasgow, Glasgow, Scotland

    2016-07-12

    Optical vortices and orbital angular momentum are currently topical subjects in the optics literature. Although seemingly esoteric, they are, in fact, the generic state of light and arise whenever three or more plane waves interfere. To be observed by eye the light must be monochromatic. Laser speckle is one such example, where the optical energy circulates around each black spot, giving a local orbital angular momentum. This talk with report three on-going studies. First, when considering a volume of interfering waves, the laser specs map out threads of complete darkness embedded in the light. Do these threads form loops? Links? Or even knots? Second, when looking through a rapidly spinning window, the image of the world on the other side is rotated: true or false? Finally, the entanglement of orbital angular momentum states means measuring how the angular position of one photons sets the angular momentum of another: is this an angular version of the EPR (Einstein, Podolsky, and Rosen) paradox?

  11. Lighting installations

    NASA Technical Reports Server (NTRS)

    Schurer, Kees

    1994-01-01

    Model computations that give the lay-out of a lighting installation have to be implemented in the real world. There, deviations from the ideal performance of just about every element of the installation will be felt. A list of possible sources of non-ideal behavior, based on practical experience, are: lamps, ballasts, reflectors, mounting position, sagging of lamps, and soiling. It is clear that with all possible deviations from the ideal the homogeneity of a real lighting installation can never be as good as the one computed. The only way to make sure it is nearly as good is by measurement of the actual light distribution. Then, an occasional adjustment or replacement may often yield a satisfactory result. This measurement should really be part of the installation contract.

  12. Polymorphous light eruption

    MedlinePlus

    Polymorphous light eruption (PMLE) is a common skin reaction in people who are sensitive to sunlight (ultraviolet light). ... Polymorphic light eruption; Photodermatosis; PMLE; Benign summer light eruption

  13. Seed germination ecology of feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes].

    PubMed

    Chauhan, Bhagirath S

    2013-01-01

    Feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes] is a C4 grass weed that has the ability to grow in both lowland and upland conditions. Experiments were conducted in the laboratory and screenhouse to evaluate the effect of environmental factors on germination, emergence, and growth of this weed species. Germination in the light/dark regime was higher at alternating day/night temperatures of 30/20 °C (98%) than at 35/25 °C (83%) or 25/15 °C (62%). Germination was completely inhibited by darkness. The osmotic potential and sodium chloride concentrations required for 50% inhibition of maximum germination were -0.7 MPa and 76 mM, respectively. The highest seedling emergence (69%) was observed from the seeds sown on the soil surface and no seedlings emerged from seeds buried at depths of 0.5 cm or more. The use of residue as mulches significantly reduced the emergence and biomass of feather lovegrass seedlings. A residue amount of 0.5 t ha(-1) was needed to suppress 50% of the maximum seedlings. Because germination was strongly stimulated by light and seedling emergence was the highest for the seeds sown on the soil surface, feather lovegrass is likely to become a problematic weed in zero-till systems. The knowledge gained from this study could help in developing effective and sustainable weed management strategies.

  14. Seed Germination Ecology of Feather Lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes

    PubMed Central

    Chauhan, Bhagirath S.

    2013-01-01

    Feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes] is a C4 grass weed that has the ability to grow in both lowland and upland conditions. Experiments were conducted in the laboratory and screenhouse to evaluate the effect of environmental factors on germination, emergence, and growth of this weed species. Germination in the light/dark regime was higher at alternating day/night temperatures of 30/20 °C (98%) than at 35/25 °C (83%) or 25/15 °C (62%). Germination was completely inhibited by darkness. The osmotic potential and sodium chloride concentrations required for 50% inhibition of maximum germination were -0.7 MPa and 76 mM, respectively. The highest seedling emergence (69%) was observed from the seeds sown on the soil surface and no seedlings emerged from seeds buried at depths of 0.5 cm or more. The use of residue as mulches significantly reduced the emergence and biomass of feather lovegrass seedlings. A residue amount of 0.5 t ha-1 was needed to suppress 50% of the maximum seedlings. Because germination was strongly stimulated by light and seedling emergence was the highest for the seeds sown on the soil surface, feather lovegrass is likely to become a problematic weed in zero-till systems. The knowledge gained from this study could help in developing effective and sustainable weed management strategies. PMID:24255700

  15. School Lighting.

    ERIC Educational Resources Information Center

    Rennhackkamp, W. M. H.

    Research gathered by the Functional Efficiency Division of the National Building Research Institute, South Africa, is aimed at providing lighting conditions under which the school child can produce his maximum effort with the least strain and fatigue. These favorable conditions are outlined along with specific examples of their realization in…

  16. Coordinate expression of AOS genes and JA accumulation: JA is not required for initiation of closing layer in wound healing tubers

    USDA-ARS?s Scientific Manuscript database

    Wounding induces a series of coordinated physiological responses essential for protection and healing of the damaged tissue. Wound-induced formation of jasmonic acid (JA) is important in defense responses in leaves, but comparatively little is known about the induction of JA biosynthesis and its ro...

  17. No-Light Light Bulbs

    ERIC Educational Resources Information Center

    Modern Schools, 1976

    1976-01-01

    A thumbnail sketch of some of the light bulbs manufactured for a purpose other than seeing. These "dark" lamps perform varied tasks including keeping food fresh, detecting and preventing disease, spurring plant growth, heating, and copying printed material. (Author/MLF)

  18. No-Light Light Bulbs

    ERIC Educational Resources Information Center

    Modern Schools, 1976

    1976-01-01

    A thumbnail sketch of some of the light bulbs manufactured for a purpose other than seeing. These "dark" lamps perform varied tasks including keeping food fresh, detecting and preventing disease, spurring plant growth, heating, and copying printed material. (Author/MLF)

  19. Light Sources and Lighting Circuits

    NASA Astrophysics Data System (ADS)

    Honda, Hisashi; Suwa, Takumi; Yasuda, Takeo; Ohtani, Yoshihiko; Maehara, Akiyoshi; Okada, Atsunori; Komatsu, Naoki; Mannami, Tomoaki

    According to the Machinery Statistics of the Ministry of Economy, Trade and Industry, the production of incandescent lamps in Japan in 2007 was 990 million units (90.0% of the previous year's total), in which the production of incandescent lamps for general lighting was 110 million units (90.0% of the previous year's total) and of tungsten-halogen lamps was 44 million units (96.6% of the previous year's total). The production of fluorescent lamps was 927 million units (93.9% of the previous year's total), in which general fluorescent lamps, excluding those for LCD back lighting, was 320 million units (87.2% of the previous year's total). Also, the production of HID lamps was 10 million units (101.5% of the previous year's total). On the other hand, when the numbers of sales are compared with the sales of the previous year, incandescent lamps for general use was 99.8%, tungsten-halogen lamps was 96.9%, fluorescent lamps was 95.9%, and HID lamps was 98.9%. Self-ballasted fluorescent lamps alone showed an increase in sales as strong as 29 million units, or 121.7% of the previous year's sales. It is considered that the switchover of incandescent lamps to HID lamps was promoted for energy conservation and carbon dioxide reduction with the problem of global warming in the background. In regard to exhibitions, Lighting Fair 2007 was held in Tokyo in March, and LIGHTFAIR INTERNATIONAL 2007 was held in New York in May. Regarding academic conferences, LS:11 (the 11th International Symposium on the Science & Technology of Light Sources) was held in Shanghai in May, and the First International Conference on White LEDs and Solid State Lighting was held in Tokyo in November. Both conferences suggested that there are strong needs and concerns now about energy conservation, saving natural resources, and restrictions of hazardous materials. In regard to incandescent lamps, the development of products aiming at higher efficacy, electric power savings, and longer life was advanced by

  20. Glareless light-emitting diode lighting tube

    NASA Astrophysics Data System (ADS)

    Chang, Rong-Seng; Li, Tung-Yen; Jwo, Ko-Wen; Wang, Sha-Wei; Tsai, Jang-Zern

    2012-03-01

    We develop a novel light bar waveguide design to produce a glareless light-emitting diode (LED) lighting tube. We design optimal parameters, such as the gap y between the tube and the reflective surface, the relative distance x between the lens and the LED, and so on. Using these parameters, we fabricate an illumination system consisting of LED light bulb installed at both ends of lighting tube. The lighting tube is shaped the same as a traditional fluorescent lighting tube in order to replace traditional lighting tubes without the modification of the lighting stand. The LED lighting tube is glareless to the observer from the side view.

  1. EDITORIAL: Controlling light with light

    NASA Astrophysics Data System (ADS)

    Hesselink, Lambertus; Feinberg, Jack; Roosen, Gerald

    2008-11-01

    The field of photorefractive physics and optics is mature and, although there is no significant commercial activity using photorefractive media, researchers in the field have had an extraordinary impact on many related areas of research and development. For example, in the late 1990s many of the telecom innovations and products were based on the interaction between light and matter. Examples include optical switches, filters, gratings, routers and light sources. The theory of multiple interacting beams of light inside a photosensitive medium, many of which were developed or further explored in photorefractive media, has found application in medicine, engineering, communication systems, displays and other photonics devices. On the occasions of the 30th anniversary of the theory of coupled wave analysis and the 10th anniversary of the meetings on Photorefractive Effects and Devices, it seemed appropriate to the meeting organizers of PR'07 to broaden the scope to include other related fields. The name of the meeting was changed to Controlling Light with Light: Photorefractive Effects, Photosensitivity, Fiber Gratings, Photonic Materials and More to attract a larger audience than traditionally would attend the more narrowly focused photorefractive meeting. To further disseminate the results of the 2007 meeting, Gerald Roosen proposed a special publication of original full research articles arising from key presentations at the meeting. The selection of papers in this Cluster Issue of Journal of Physics D: Applied Physics is the result of that initiative. We would like to thank all the authors for their contributions, the committee members for their valuable insight and efforts in helping to organize the meeting, and the Optical Society of America for their professional assistance throughout the preparation period of the meeting as well as during the three beautiful days in Lake Tahoe, CA.

  2. Effect of MeJA treatment on polyamine, energy status and anthracnose rot of loquat fruit.

    PubMed

    Cao, Shifeng; Cai, Yuting; Yang, Zhenfeng; Joyce, Daryl C; Zheng, Yonghua

    2014-02-15

    The effect of methyl jasmonate (MeJA) on changes in polyamines content and energy status and their relation to disease resistance was investigated. Freshly harvested loquat fruit were treated with 10 μmol l(-1) MeJA and wound inoculated with Colletotrichum acutatum spore suspension (1.0 × 10(5) spores ml(-1)) after 24h, and then stored at 20 °C for 6 days. MeJA treatment significantly reduced decay incidence. MeJA treated fruit manifested higher contents of polyamines (putrescine, spermidine and spermine) compared with the control fruit, during storage. MeJA treatment also maintained higher levels of adenosine triphosphate, and suppressed an increase in adenosine monophosphate content in loquat fruit. These results suggest that MeJA treatment may inhibit anthracnose rot by increasing polyamine content and maintaining the energy status. Copyright © 2013. Published by Elsevier Ltd.

  3. Mitochondrial chaperone DnaJA3 induces Drp1-dependent mitochondrial fragmentation.

    PubMed

    Elwi, Adam N; Lee, Byoungchun; Meijndert, H Christopher; Braun, Janice E A; Kim, Sung-Woo

    2012-08-01

    Mitochondrial morphology is dynamic and controlled by coordinated fusion and fission pathways. The role of mitochondrial chaperones in mitochondrial morphological changes and pathology is currently unclear. Here we report that altered levels of DnaJA3 (Tid1/mtHsp40) a mitochondrial member of the DnaJ protein family, and heat shock protein (Hsp) co-chaperone of matrix 70 kDa Hsp70 (mtHsp70/mortalin/HSPA9), induces mitochondrial fragmentation. Suppression of DnaJA3 induced mitochondrial fragmentation in HeLa cells. Elevated levels of DnaJA3 in normal Hs68 fibroblast cells and HeLa, SKN-SH, U87 and U251 cancer cell lines induces mitochondrial fragmentation. Mitochondrial fragmentation induction was not observed in HeLa cells when other DnaJA family members, or mitochondrial DnaJ protein HSC20, were ectopically expressed, indicating that the effects on mitochondrial morphology were specific to DnaJA3. We show that the DnaJ domain (amino acids 88-168) of DnaJA3 is sufficient for the induction of mitochondrial fragmentation. Furthermore, an H121Q point mutation of the DnaJ domain, which abrogates interaction and activation of mtHsp70 ATPase, eliminates fragmentation induced by DnaJA3. This suggests that DnaJA3 interaction with mtHsp70 may be critical in mitochondrial morphological changes. DnaJA3-induced mitochondrial fragmentation was dependent on fission factor dynamin-related protein 1 (Drp1). Ectopic expression of the mitofusins (Mfn1 and Mfn2), however, does not rescue DnaJA3-induced mitochondrial fragmentation. Lastly, elevated levels of DnaJA3 inducing mitochondrial fragmentation were associated with reduction in cell viability. Taken together, elevated DnaJA3 induces Drp1-depedendent mitochondrial fragmentation and decreased cell viability.

  4. Light fantastic

    NASA Astrophysics Data System (ADS)

    2010-05-01

    The laser has become so ubiquitous that it would be impossible to acknowledge everyone who has played a role in its success. As Roy Glauber said at the 2005 Nobel-prize banquet, when it comes to lasers, "many hands make light work". And he should know: the prize Glauber shared with fellow optics pioneers John Hall and Theodore Hänsch is one of more than 10 Nobels awarded (so far!) for laser-related research. This timeline marking 50 years of the laser contains Physics World's pick of events from laser history, including prizes (gold text), applications (green) and "firsts" (blue).

  5. Synthesis, structural characterization and biological activity of two diastereomeric JA-Ile macrolactones.

    PubMed

    Jimenez-Aleman, Guillermo H; Machado, Ricardo A R; Görls, Helmar; Baldwin, Ian T; Boland, Wilhelm

    2015-06-07

    Jasmonates are phytohormones involved in a wide range of plant processes, including growth, development, senescence, and defense. Jasmonoyl-L-isoleucine (JA-Ile, 2), an amino acid conjugate of jasmonic acid (JA, 1), has been identified as a bioactive endogenous jasmonate. However, JA-Ile (2) analogues trigger different responses in the plant. ω-Hydroxylation of the pentenyl side chain leads to the inactive 12-OH-JA-Ile (3) acting as a “stop” signal. On the other hand, a lactone derivative of 12-OH-JA (5) (jasmine ketolactone, JKL) occurs in nature, although with no known biological function. Inspired by the chemical structure of JKL (6) and in order to further explore the potential biological activities of 12-modified JA-Ile derivatives, we synthesized two macrolactones (JA-Ile-lactones (4a) and (4b)) derived from 12-OH-JA-Ile (3). The biological activity of (4a) and (4b) was tested for their ability to elicit nicotine production, a well-known jasmonate dependent secondary metabolite. Both macrolactones showed strong biological activity, inducing nicotine accumulation to a similar extent as methyl jasmonate does in Nicotiana attenuata leaves. Surprisingly, the highest nicotine contents were found in plants treated with the JA-Ile-lactone (4b), which has (3S,7S) configuration at the cyclopentanone not known from natural jasmonates. Macrolactone (4a) is a valuable standard to explore for its occurrence in nature.

  6. The mealybug Phenacoccus solenopsis suppresses plant defense responses by manipulating JA-SA crosstalk

    PubMed Central

    Zhang, Peng-Jun; Huang, Fang; Zhang, Jin-Ming; Wei, Jia-Ning; Lu, Yao-Bin

    2015-01-01

    Induced plant defenses against herbivores are modulated by jasmonic acid-, salicylic acid-, and ethylene-signaling pathways. Although there is evidence that some pathogens suppress plant defenses by interfering with the crosstalk between different signaling pathways, such evidence is scarce for herbivores. Here, we demonstrate that the mealybug Phenacoccus solenopsis suppresses the induced defenses in tomato. We found that exogenous JA, but not SA, significantly decreased mealybug feeding time and reduced nymphal performance. In addition, constitutive activation of JA signaling in 35s::prosys plants reduced mealybug survival. These data indicate that the JA signaling pathway plays a key role in mediating the defense responses against P. solenopsis. We also found that mealybug feeding decreased JA production and JA-dependent defense gene expression, but increased SA accumulation and SA-dependent gene expression. In SA-deficient plants, mealybug feeding did not suppress but activated JA accumulation, indicating that the suppression of JA-regulated defenses depends on the SA signaling pathway. Mealybugs benefit from suppression of JA-regulated defenses by exhibiting enhanced nymphal performance. These findings confirm that P. solenopsis manipulates plants for its own benefits by modulating the JA-SA crosstalk and thereby suppressing induced defenses. PMID:25790868

  7. Red/Far Red Light Controls Arbuscular Mycorrhizal Colonization via Jasmonic Acid and Strigolactone Signaling.

    PubMed

    Nagata, Maki; Yamamoto, Naoya; Shigeyama, Tamaki; Terasawa, Yohei; Anai, Toyoaki; Sakai, Tatsuya; Inada, Sayaka; Arima, Susumu; Hashiguchi, Masatsugu; Akashi, Ryo; Nakayama, Hideyuki; Ueno, Daisuke; Hirsch, Ann M; Suzuki, Akihiro

    2015-11-01

    Establishment of a nitrogen-fixing symbiosis between legumes and rhizobia not only requires sufficient photosynthate, but also the sensing of the ratio of red to far red (R/FR) light. Here, we show that R/FR light sensing also positively influences the arbuscular mycorrhizal (AM) symbiosis of a legume and a non-legume through jasmonic acid (JA) and strigolactone (SL) signaling. The level of AM colonization in high R/FR light-grown tomato and Lotus japonicus significantly increased compared with that determined for low R/FR light-grown plants. Transcripts for JA-related genes were also elevated under high R/FR conditions. The root exudates derived from high R/FR light-grown plants contained more (+)-5-deoxystrigol, an AM-fungal hyphal branching inducer, than those from low R/FR light-grown plants. In summary, high R/FR light changes not only the levels of JA and SL synthesis, but also the composition of plant root exudates released into the rhizosphere, in this way augmenting the AM symbiosis.

  8. Measuring Light

    NASA Image and Video Library

    2017-09-27

    On July 13, 2011, Don Perovich, of Cold Regions Research and Engineering Laboratory, measured the light that drives photosynthesis at the sixth sea ice station of the 2011 ICESCAPE mission. The ICESCAPE mission, or "Impacts of Climate on Ecosystems and Chemistry of the Arctic Pacific Environment," is a NASA shipborne investigation to study how changing conditions in the Arctic affect the ocean's chemistry and ecosystems. The bulk of the research took place in the Beaufort and Chukchi seas in summer 2010 and 2011. Credit: NASA/Kathryn Hansen NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  9. Light Echo

    NASA Image and Video Library

    2017-09-27

    "Light Echo" Illuminates Dust Around Supergiant Star V838 Monocerotis (V838 Mon) Credit: NASA and The Hubble Heritage Team (AURA/STScI) The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute conducts Hubble science operations. Goddard is responsible for HST project management, including mission and science operations, servicing missions, and all associated development activities. To learn more about the Hubble Space Telescope go here: www.nasa.gov/mission_pages/hubble/main/index.html NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe. Follow us on Twitter Join us on Facebook

  10. Novel bioactive oxazolomycin isomers produced by Streptomyces albus JA3453.

    PubMed

    Kanzaki, H; Wada, K; Nitoda, T; Kawazu, K

    1998-03-01

    Two novel oxazolomycin isomers, oxazolomycins B (2) and C (3), were isolated from the fermentation broth of an oxazolomycin-producing strain, Streptomyces albus JA3453. Both compounds are geometrical isomers of oxazolomycin (1), the configurations of their triene moieties being (4'E, 6'E, 8'E) (2) and (4'Z, 6'E, 8'E) (3) while that of oxazolomycin (1) is (4'Z, 6'Z, 8'E). Compounds 2 and 3 exhibited potent inhibitory activity against crown gall formation with the same MIC (0.8 microgram/disk) as oxazolomycin. Compounds 2 and 3 showed no antibacterial activity against Agrobacterium tumefaciens, in contrast to oxazolomycin which has specific anti-A. tumefaciens activity.

  11. Lighting the Learning Environment.

    ERIC Educational Resources Information Center

    Fielding, Randall

    2000-01-01

    Explores the benefits and pitfalls of day lighting, indirect light, and full-spectrum lamps for general illumination and accent lighting in classrooms. Discussions include lighting considerations in areas where computers are used and fixture cost factors versus efficiency. (GR)

  12. Lighting the Learning Environment.

    ERIC Educational Resources Information Center

    Fielding, Randall

    2000-01-01

    Explores the benefits and pitfalls of day lighting, indirect light, and full-spectrum lamps for general illumination and accent lighting in classrooms. Discussions include lighting considerations in areas where computers are used and fixture cost factors versus efficiency. (GR)

  13. Traffic Lights: Red Light Spells Danger.

    ERIC Educational Resources Information Center

    Reed, Chris

    2001-01-01

    A "traffic light" model provides youth groups with a means to evaluate the risk level of specific behaviors and agree upon the management of such behaviors. Designed for outdoor pursuits, the model may be used in other environments. Suggestions for ways to discuss red-light, yellow-light, and green-light behaviors are included. (SV)

  14. Light and Libraries.

    ERIC Educational Resources Information Center

    Scherer, Jeffrey

    1999-01-01

    Addresses how to integrate various types of light within the context of library design. Discusses light basics; the light spectrum; light measurement; reflectance; glare and brightness ratio; daylighting; electric lighting; and computer screens and lighting. Includes a checklist for plan review. (Author/LRW)

  15. COI1, a jasmonate receptor, is involved in ethylene-induced inhibition of Arabidopsis root growth in the light

    PubMed Central

    Adams, Eri; Turner, John

    2010-01-01

    Plant response to stress is orchestrated by hormone signalling pathways including those activated by jasmonates (JAs) and by ethylene, both of which stunt root growth. COI1 is a JA receptor and is required for the known responses to this hormone. It was observed that the coi1 mutant, which is largely unresponsive to growth inhibition by JAs, was also partially unresponsive to growth inhibition by ethylene and by its immediate precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), in the light but not in the dark. Although COI1 was required for this response to ACC, other components of the JA signal perception pathway were not. Mutants selected for insensitivity to ethylene, including etr1, ein2, and ein3, showed greater ACC-induced root growth inhibition in the light than in the dark. However, the double mutants etr1;coi1, ein2;coi1, and ein3;coi1, and coi1 seedlings treated with silver ions to block the ethylene receptors showed almost complete unresponsiveness to ACC-induced root growth inhibition in the light. The light requirement for the COI1-mediated growth inhibition by ACC was for long photoperiods, and the ACC response was not abolished by mutations in the known photoreceptors. The complementation assay indicated that SCF complex assembly was not required for COI1 function in the ACC response, in contrast to the JA response. It is concluded that COI1 is required for the light-dependent, JA-independent, root growth inhibition by ethylene. PMID:20699268

  16. COI1, a jasmonate receptor, is involved in ethylene-induced inhibition of Arabidopsis root growth in the light.

    PubMed

    Adams, Eri; Turner, John

    2010-10-01

    Plant response to stress is orchestrated by hormone signalling pathways including those activated by jasmonates (JAs) and by ethylene, both of which stunt root growth. COI1 is a JA receptor and is required for the known responses to this hormone. It was observed that the coi1 mutant, which is largely unresponsive to growth inhibition by JAs, was also partially unresponsive to growth inhibition by ethylene and by its immediate precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), in the light but not in the dark. Although COI1 was required for this response to ACC, other components of the JA signal perception pathway were not. Mutants selected for insensitivity to ethylene, including etr1, ein2, and ein3, showed greater ACC-induced root growth inhibition in the light than in the dark. However, the double mutants etr1;coi1, ein2;coi1, and ein3;coi1, and coi1 seedlings treated with silver ions to block the ethylene receptors showed almost complete unresponsiveness to ACC-induced root growth inhibition in the light. The light requirement for the COI1-mediated growth inhibition by ACC was for long photoperiods, and the ACC response was not abolished by mutations in the known photoreceptors. The complementation assay indicated that SCF complex assembly was not required for COI1 function in the ACC response, in contrast to the JA response. It is concluded that COI1 is required for the light-dependent, JA-independent, root growth inhibition by ethylene.

  17. Lighting Options for Homes.

    SciTech Connect

    Baker, W.S.

    1991-04-01

    This report covers many aspects of various lighting options for homes. Types of light sources described include natural light, artificial light, incandescent lamps, fluorescent lamps, and high intensity discharge lamps. A light source selection guide gives the physical characteristics of these, design considerations, and common applications. Color, strategies for efficient lighting, and types of lighting are discussed. There is one section giving tips for various situations in specific rooms. Rooms and types of fixtures are shown on a matrix with watts saved by using the recommended type lighting for that room and room location. A major emphasis of this report is saving energy by utilizing the most suitable, recommended lighting option. (BN)

  18. Mobile lighting apparatus

    SciTech Connect

    Roe, George Michael; Klebanoff, Leonard Elliott; Rea, Gerald W; Drake, Robert A; Johnson, Terry A; Wingert, Steven John; Damberger, Thomas A; Skradski, Thomas J; Radley, Christopher James; Oros, James M; Schuttinger, Paul G; Grupp, David J; Prey, Stephen Carl

    2013-05-14

    A mobile lighting apparatus includes a portable frame such as a moveable trailer or skid having a light tower thereon. The light tower is moveable from a stowed position to a deployed position. A hydrogen-powered fuel cell is located on the portable frame to provide electrical power to an array of the energy efficient lights located on the light tower.

  19. Light up My Life

    ERIC Educational Resources Information Center

    Kellett, Sarah

    2015-01-01

    Simply stated, light is nature's way of transferring energy through space. Discussions of light usually refer to visible light, which is perceived by the human eye and is responsible for the sense of sight. We see however, only a small part of the light spectrum. Light connects us as we sit and tell yarns around camp fires. Yet, one in every four…

  20. Light up My Life

    ERIC Educational Resources Information Center

    Kellett, Sarah

    2015-01-01

    Simply stated, light is nature's way of transferring energy through space. Discussions of light usually refer to visible light, which is perceived by the human eye and is responsible for the sense of sight. We see however, only a small part of the light spectrum. Light connects us as we sit and tell yarns around camp fires. Yet, one in every four…

  1. THE PROGENITOR OF SN 2011ja: CLUES FROM CIRCUMSTELLAR INTERACTION

    SciTech Connect

    Chakraborti, Sayan; Ray, Alak; Yadav, Naveen; Smith, Randall; Ryder, Stuart; Sutaria, Firoza; Dwarkadas, Vikram V.; Chandra, Poonam; Pooley, David; Roy, Rupak

    2013-09-01

    Massive stars, possibly red supergiants, which retain extended hydrogen envelopes until core collapse, produce Type II plateau (IIP) supernovae. The ejecta from these explosions shocks the circumstellar matter originating from the mass loss of the progenitor during the final phases of its life. This interaction accelerates particles to relativistic energies which then lose energy via synchrotron radiation in the shock-amplified magnetic fields and inverse Compton scattering against optical photons from the supernova. These processes produce different signatures in the radio and X-ray parts of the electromagnetic spectrum. Observed together, they allow us to break the degeneracy between shock acceleration and magnetic field amplification. In this work, we use X-rays observations from the Chandra and radio observations from the Australia Telescope Compact Array to study the relative importance of processes which accelerate particles and those which amplify magnetic fields in producing the non-thermal radiation from SN 2011ja. We use radio observations to constrain the explosion date. Multiple Chandra observations allow us to probe the history of variable mass loss from the progenitor. The ejecta expands into a low-density bubble followed by interaction with a higher density wind from a red supergiant consistent with M{sub ZAMS} {approx}> 12 M{sub Sun }. Our results suggest that a fraction of Type IIP supernovae may interact with circumstellar media set up by non-steady winds.

  2. Serum Free Light Chains

    MedlinePlus

    ... and services. Advertising & Sponsorship: Policy | Opportunities Serum Free Light Chains Share this page: Was this page helpful? Also known as: Free Light Chains; SFLC; FLC; Kappa and Lambda Free Light ...

  3. Optics for natural lighting

    NASA Technical Reports Server (NTRS)

    Edwards, H. B.

    1978-01-01

    Energy-saving optics utilize sky and sun for lighting. Innovative optical arrangements for transmitting outdoor light into building interiors are decribed using flat white and mirrored surfaces for converging and diverging light pipes.

  4. Light 'Em Up.

    ERIC Educational Resources Information Center

    Wiese, Paul J.; Lindstrom, Chuck

    1998-01-01

    Provides advice on designing sports-field lighting that can help balance design with cost and lighting-system performance. Areas addressed include system installation, pole placement, light-spillage control, and maintenance. (GR)

  5. Fingerprints in the Light

    NASA Image and Video Library

    2005-03-01

    This spectrum shows the light from a dusty, distant galaxy located 11 billion light-years away. The galaxy is invisible to optical telescopes, but NASA Spitzer Space Telescope captured the light from it and dozens of other similar galaxies.

  6. Light 'Em Up.

    ERIC Educational Resources Information Center

    Wiese, Paul J.; Lindstrom, Chuck

    1998-01-01

    Provides advice on designing sports-field lighting that can help balance design with cost and lighting-system performance. Areas addressed include system installation, pole placement, light-spillage control, and maintenance. (GR)

  7. Mutations in jasmonoyl-L-isoleucine-12-hydroxylases suppress multiple JA-dependent wound responses in Arabidopsis thaliana.

    PubMed

    Poudel, Arati N; Zhang, Tong; Kwasniewski, Misha; Nakabayashi, Ryo; Saito, Kazuki; Koo, Abraham J

    2016-09-01

    Plants rapidly perceive tissue damage, such as that inflicted by insects, and activate several key defense responses. The importance of the fatty acid-derived hormone jasmonates (JA) in dictating these wound responses has been recognized for many years. However, important features pertaining to the regulation of the JA pathway are still not well understood. One key unknown is the inactivation mechanism of the JA pathway and its relationship with plant response to wounding. Arabidopsis cytochrome P450 enzymes in the CYP94 clade metabolize jasmonoyl-L-isoleucine (JA-Ile), a major metabolite of JA responsible for many biological effects attributed to the JA signaling pathway; thus, CYP94s are expected to contribute to the attenuation of JA-Ile-dependent wound responses. To directly test this, we created the double and triple knock-out mutants of three CYP94 genes, CYP94B1, CYP94B3, and CYP94C1. The mutations blocked the oxidation steps and caused JA-Ile to accumulate 3-4-fold the WT levels in the wounded leaves. Surprisingly, over accumulation of JA-Ile did not lead to a stronger wound response. On the contrary, the mutants displayed a series of symptoms reminiscent of JA-Ile deficiency, including resistance to wound-induced growth inhibition, decreased anthocyanin and trichomes, and increased susceptibility to insects. The mutants, however, responded normally to exogenous JA treatments, indicating that JA perception or signaling pathways were intact. Untargeted metabolite analyses revealed >40% reduction in wound-inducible metabolites in the mutants. These observations raise questions about the current JA signaling model and point toward a more complex model perhaps involving JA derivatives and/or feedback mechanisms. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Update from the Japanese Center for the Validation of Alternative Methods (JaCVAM).

    PubMed

    Kojima, Hajime

    2013-12-01

    The Japanese Center for the Validation of Alternative Methods (JaCVAM) was established in 2005 to promote the use of alternatives to animal testing in regulatory studies, thereby replacing, reducing, or refining the use of animals, according to the Three Rs principles. JaCVAM assesses the utility, limitations and suitability for use in regulatory studies, of test methods needed to determine the safety of chemicals and other materials. JaCVAM also organises and performs validation studies of new test methods, when necessary. In addition, JaCVAM co-operates and collaborates with similar organisations in related fields, both in Japan and internationally, which also enables JaCVAM to provide input during the establishment of guidelines for new alternative experimental methods. These activities help facilitate application and approval processes for the manufacture and sale of pharmaceuticals, chemicals, pesticides, and other products, as well as for revisions to standards for cosmetic products. In this manner, JaCVAM plays a leadership role in the introduction of new alternative experimental methods for regulatory acceptance in Japan.

  9. Shared binding sites in Lepidoptera for Bacillus thuringiensis Cry1Ja and Cry1A toxins.

    PubMed

    Herrero, S; González-Cabrera, J; Tabashnik, B E; Ferré, J

    2001-12-01

    Bacillus thuringiensis toxins act by binding to specific target sites in the insect midgut epithelial membrane. The best-known mechanism of resistance to B. thuringiensis toxins is reduced binding to target sites. Because alteration of a binding site shared by several toxins may cause resistance to all of them, knowledge of which toxins share binding sites is useful for predicting cross-resistance. Conversely, cross-resistance among toxins suggests that the toxins share a binding site. At least two strains of diamondback moth (Plutella xylostella) with resistance to Cry1A toxins and reduced binding of Cry1A toxins have strong cross-resistance to Cry1Ja. Thus, we hypothesized that Cry1Ja shares binding sites with Cry1A toxins. We tested this hypothesis in six moth and butterfly species, each from a different family: Cacyreus marshalli (Lycaenidae), Lobesia botrana (Tortricidae), Manduca sexta (Sphingidae), Pectinophora gossypiella (Gelechiidae), P. xylostella (Plutellidae), and Spodoptera exigua (Noctuidae). Although the extent of competition varied among species, experiments with biotinylated Cry1Ja and radiolabeled Cry1Ac showed that Cry1Ja and Cry1Ac competed for binding sites in all six species. A recent report also indicates shared binding sites for Cry1Ja and Cry1A toxins in Heliothis virescens (Noctuidae). Thus, shared binding sites for Cry1Ja and Cry1A occur in all lepidopteran species tested so far.

  10. PFP Emergency Lighting Study

    SciTech Connect

    BUSCH, M.S.

    2000-02-02

    NFPA 101, section 5-9 mandates that, where required by building classification, all designated emergency egress routes be provided with adequate emergency lighting in the event of a normal lighting outage. Emergency lighting is to be arranged so that egress routes are illuminated to an average of 1.0 footcandle with a minimum at any point of 0.1 footcandle, as measured at floor level. These levels are permitted to drop to 60% of their original value over the required 90 minute emergency lighting duration after a power outage. The Plutonium Finishing Plant (PFP) has two designations for battery powered egress lights ''Emergency Lights'' are those battery powered lights required by NFPA 101 to provide lighting along officially designated egress routes in those buildings meeting the correct occupancy requirements. Emergency Lights are maintained on a monthly basis by procedure ZSR-12N-001. ''Backup Lights'' are battery powered lights not required by NFPA, but installed in areas where additional light may be needed. The Backup Light locations were identified by PFP Safety and Engineering based on several factors. (1) General occupancy and type of work in the area. Areas occupied briefly during a shiftly surveillance do not require backup lighting while a room occupied fairly frequently or for significant lengths of time will need one or two Backup lights to provide general illumination of the egress points. (2) Complexity of the egress routes. Office spaces with a standard hallway/room configuration will not require Backup Lights while a large room with several subdivisions or irregularly placed rooms, doors, and equipment will require Backup Lights to make egress safer. (3) Reasonable balance between the safety benefits of additional lighting and the man-hours/exposure required for periodic light maintenance. In some plant areas such as building 236-Z, the additional maintenance time and risk of contamination do not warrant having Backup Lights installed in all rooms

  11. Lighting in Schools.

    ERIC Educational Resources Information Center

    Department of Education and Science, London (England).

    The application of good lighting principles to school design is discussed. Part 1 of the study is concerned with the general principles of light and vision as they affect lighting in schools. Parts 2 and 3 deal with the application of these principles to daylighting and artificial lighting. Part 4 discusses the circumstances in which the…

  12. Pedestrian Friendly Outdoor Lighting

    SciTech Connect

    Miller, N. J.; Koltai, R. N.; McGowan, T. K.

    2013-12-01

    The GATEWAY program followed two pedestrian-scale lighting projects that required multiple mockups – one at Stanford University in California and the other at Chautauqua Institution in upstate New York. The report provides insight into pedestrian lighting criteria, how they differ from street and area lighting criteria, and how solid-state lighting can be better applied in pedestrian applications.

  13. Lighting in Schools.

    ERIC Educational Resources Information Center

    Department of Education and Science, London (England).

    The application of good lighting principles to school design is discussed. Part 1 of the study is concerned with the general principles of light and vision as they affect lighting in schools. Parts 2 and 3 deal with the application of these principles to daylighting and artificial lighting. Part 4 discusses the circumstances in which the…

  14. Environmental Outdoor Lighting

    NASA Astrophysics Data System (ADS)

    Nelson, D.

    2004-05-01

    Lighting for the outdoor environment presents challenges not usually found in interior lighting. Outdoors, the universal standard is the daytime sun, yet nighttime electric lighting falls far short of daylight. This presentation provides guidance in dealing with these shortcomings, allowing electric lighting systems to solve multiple needs while being responsive to the need for quality exterior lighting. Main aspects include visual issues, ordinances, sources, energy conservation, structure, softscape and hardscape, roadways and walkways, retail and parking lots, sports, and outdoor hospitality lighting. We will review many of the present recommendations for such lighting applications, ones designed to minimize any adverse effects.

  15. Light Curing in Dentistry.

    PubMed

    Price, Richard B T

    2017-10-01

    The ability to light cure resins 'on demand' in the mouth has revolutionized dentistry. However, there is a widespread lack of understanding of what is required for successful light curing in the mouth. Most instructions simply tell the user to 'light cure for xx seconds' without describing any of the nuances of how to successfully light cure a resin. This article provides a brief description of light curing. At the end, some recommendations are made to help when purchasing a curing light and how to improve the use of the curing light. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Concept of white light in stage lighting

    NASA Astrophysics Data System (ADS)

    Rinaldi, Mauricio R.

    2002-06-01

    In perceiving objects, generally we see them in a white light situation. But, actually, there is not an absolute white, in such a manner that the different light sources have a determined kind of white, what it is known as color temperature. Even the white light may be of different kinds (different color temperature), the individual mind tends to perceive it as the same kind of white, that is to say, there is in our mind a psychological function by which we operate an integration in the perception in order to do the object perceptually invariable. On the other hand, it is a common practice in stage lighting to use color light sources. It is a well known phenomenon that a color of light produces a change in the object color perception. However, when we go to theater, we see the objects as having their real color, even if the lighting is not white. In this paper the concept of white light in stage lighting is presented, showing its possibilities of aesthetical expression.

  17. Lights illuminate surfaces superluminally

    NASA Astrophysics Data System (ADS)

    Nemiroff, Robert J.; Zhong, Qi; Lilleskov, Elias

    2016-07-01

    When a light bulb is turned on, light moves away from it at speed c, by definition. When light from this bulb illuminates a surface, however, this illumination front is not constrained to move at speed c. A simple proof is given that this illumination front always moves faster than c. Generalized, when any compact light source itself varies, this information spreads across all of the surfaces it illuminates at speeds faster than light.

  18. The Properties of Light

    NASA Astrophysics Data System (ADS)

    Haglund, Richard F.

    The mystery of light has formed the core of creation stories in every culture, and attracted the earnest attentions of philosophers since at least the fifth century BCE. Their questions have ranged from how and what we see, to the interaction of light with material bodies, and finally to the nature of light itself. This chapter begins with a brief intellectual history of light from ancient Greece to the end of the 19th century. After introducing the physical parameterization of light in terms of standard units, three concepts of light are introduced: light as a wave, light as a quantum particle, and light as a quantum field. After highlighting the distinctive characteristics of light beams from various sources - thermal radiation, luminescence from atoms and molecules, and synchrotron light sources - the distinctive physical characteristics of light beams are examined in some detail. The chapter concludes with a survey of the statistical and quantum-mechanical properties of light beams. In the appropriate limits, this treatment not only recovers the classical description of light waves and the semiclassical view of light as a stream of quanta, but also forms a consistent description of quantum phenomena - such as interference phenomena generated by single photons - that have no classical analogs.

  19. Expression of a Flax Allene Oxide Synthase cDNA Leads to Increased Endogenous Jasmonic Acid (JA) Levels in Transgenic Potato Plants but Not to a Corresponding Activation of JA-Responding Genes.

    PubMed Central

    Harms, K.; Atzorn, R.; Brash, A.; Kuhn, H.; Wasternack, C.; Willmitzer, L.; Pena-Cortes, H.

    1995-01-01

    Both jasmonic acid (JA) and its methyl ester, methyl jasmonate (MeJA), are thought to be significant components of the signaling pathway regulating the expression of plant defense genes in response to various stresses. JA and MeJA are plant lipid derivatives synthesized from [alpha]-linolenic acid by a lipoxygenase-mediated oxygenation leading to 13-hydroperoxylinolenic acid, which is subsequently transformed by the action of allene oxide synthase (AOS) and additional modification steps. AOS converts lipoxygenase-derived fatty acid hydroperoxide to allene epoxide, which is the precursor for JA formation. Overexpression of flax AOS cDNA under the regulation of the cauliflower mosaic virus 35S promoter in transgenic potato plants led to an increase in the endogenous level of JA. Transgenic plants had six- to 12-fold higher levels of JA than the nontransformed plants. Increased levels of JA have been observed when potato and tomato plants are mechanically wounded. Under these conditions, the proteinase inhibitor II (pin2) genes are expressed in the leaves. Despite the fact that the transgenic plants had levels of JA similar to those found in nontransgenic wounded plants, pin2 genes were not constitutively expressed in the leaves of these plants. Transgenic plants with increased levels of JA did not show changes in water state or in the expression of water stress-responsive genes. Furthermore, the transgenic plants overexpressing the flax AOS gene, and containing elevated levels of JA, responded to wounding or water stress by a further increase in JA and by activating the expression of either wound- or water stress-inducible genes. Protein gel blot analysis demonstrated that the flax-derived AOS protein accumulated in the chloroplasts of the transgenic plants. PMID:12242357

  20. Optimal functional levels of activation-induced deaminase specifically require the Hsp40 DnaJa1

    PubMed Central

    Orthwein, Alexandre; Zahn, Astrid; Methot, Stephen P; Godin, David; Conticello, Silvestro G; Terada, Kazutoyo; Di Noia, Javier M

    2012-01-01

    The enzyme activation-induced deaminase (AID) deaminates deoxycytidine at the immunoglobulin genes, thereby initiating antibody affinity maturation and isotype class switching during immune responses. In contrast, off-target DNA damage caused by AID is oncogenic. Central to balancing immunity and cancer is AID regulation, including the mechanisms determining AID protein levels. We describe a specific functional interaction between AID and the Hsp40 DnaJa1, which provides insight into the function of both proteins. Although both major cytoplasmic type I Hsp40s, DnaJa1 and DnaJa2, are induced upon B-cell activation and interact with AID in vitro, only DnaJa1 overexpression increases AID levels and biological activity in cell lines. Conversely, DnaJa1, but not DnaJa2, depletion reduces AID levels, stability and isotype switching. In vivo, DnaJa1-deficient mice display compromised response to immunization, AID protein and isotype switching levels being reduced by half. Moreover, DnaJa1 farnesylation is required to maintain, and farnesyltransferase inhibition reduces, AID protein levels in B cells. Thus, DnaJa1 is a limiting factor that plays a non-redundant role in the functional stabilization of AID. PMID:22085931

  1. Interference and Polarized Light.

    ERIC Educational Resources Information Center

    Charas, Seymour

    1988-01-01

    Discusses a demonstration of interference phenomena using three sheets of polaroid material, a light source, and a light meter. Describes instructional procedures with mathematical expressions and a diagram. (YP)

  2. Dark and Light Titan

    NASA Image and Video Library

    2010-09-08

    NASA Cassini spacecraft examines Titan dark and light seasonal hemispheric dichotomy as it images the moon with a filter sensitive to near-infrared light. This image also shows Titan north polar hood.

  3. Plants under continuous light.

    PubMed

    Velez-Ramirez, Aaron I; van Ieperen, Wim; Vreugdenhil, Dick; Millenaar, Frank F

    2011-06-01

    Continuous light is an essential tool for understanding the plant circadian clock. Additionally, continuous light might increase greenhouse food production. However, using continuous light in research and practice has its challenges. For instance, most of the circadian clock-oriented experiments were performed under continuous light; consequently, interactions between the circadian clock and the light signaling pathway were overlooked. Furthermore, in some plant species continuous light induces severe injury, which is only poorly understood so far. In this review paper, we aim to combine the current knowledge with a modern conceptual framework. Modern genomic tools and rediscovered continuous light-tolerant tomato species (Solanum spp.) could boost the understanding of the physiology of plants under continuous light. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Automatic lighting controls demonstration

    SciTech Connect

    Rubinstein, F.; Verderber, R.

    1990-03-01

    The purpose of this work was to demonstrate, in a real building situation, the energy and peak demand reduction capabilities of an electronically ballasted lighting control system that can utilize all types of control strategies to efficiently manage lighting. The project has demonstrated that a state-of-the-art electronically ballasted dimmable lighting system can reduce energy and lighting demand by as least 50% using various combinations of control strategies. By reducing light levels over circulation areas (tuning) and reducing after hours light levels to accommodate the less stringent lighting demands of the cleaning crew (scheduling), lighting energy consumption on weekdays was reduced an average of 54% relative to the initial condition. 10 refs., 14 figs., 3 tabs.

  5. The NICU Lighted Environment.

    PubMed

    Rea, Mark S; Figueiro, Mariana G

    2016-12-01

    Lighting technologies are rapidly evolving, creating many opportunities for good lighting within the NICU. With the widespread adoption of advanced solid-state lighting technologies, lighting no longer needs to be static. Rather, lighting systems can be more easily adjusted to the different and changing visual and non-visual needs of the professional staff, infants and family members throughout the 24-hour day. This paper provides a conceptual framework for defining good lighting in the NICU, recognizing the needs of various constituent groups, each with very different needs from the lighting. Several other papers on the topic of lighting for various constituent groups at different times of the day in the NICU are summarized. Attention is given specifically to the Recommended Standards for Newborn ICU Design, a consensus standard developed by a wide range of experts, to help the reader translate this conceptual framework to practice.

  6. A balanced JA/ABA status may correlate with adaptation to osmotic stress in Vitis cells.

    PubMed

    Ismail, Ahmed; Seo, Mitsunori; Takebayashi, Yumiko; Kamiya, Yuji; Nick, Peter

    2015-08-01

    Water-related stress is considered a major type of plant stress. Osmotic stress, in particular, represents the common part of all water-related stresses. Therefore, plants have evolved different adaptive mechanisms to cope with osmotic-related disturbances. In the current work, two grapevine cell lines that differ in their osmotic adaptability, Vitis rupestris and Vitis riparia, were investigated under mannitol-induced osmotic stress. To dissect signals that lead to adaptability from those related to sensitivity, osmotic-triggered responses with respect to jasmonic acid (JA) and its active form JA-Ile, abscisic acid (ABA), and stilbene compounds, as well as the expression of their related genes were observed. In addition, the transcript levels of the cellular homeostasis gene NHX1 were examined. The data are discussed with a hypothesis suggesting that a balance of JA and ABA status might correlate with cellular responses, either guiding cells to sensitivity or to progress toward adaptation.

  7. Architectural Physics: Lighting.

    ERIC Educational Resources Information Center

    Hopkinson, R. G.

    The author coordinates the many diverse branches of knowledge which have dealt with the field of lighting--physiology, psychology, engineering, physics, and architectural design. Part I, "The Elements of Architectural Physics", discusses the physiological aspects of lighting, visual performance, lighting design, calculations and measurements of…

  8. Seeing the Light

    ERIC Educational Resources Information Center

    Sportel, Samuel; Bruxvoort, Crystal; Jadrich, James

    2009-01-01

    Conceptually, students are typically introduced to light as a type of wave. However, children struggle to understand this model because it is highly abstract. Light can be represented more concretely using the photon model. According to this scientific model, light emanates from sources as tiny "packets" of energy (called "photons") that move in…

  9. Seeing the Light

    ERIC Educational Resources Information Center

    Sportel, Samuel; Bruxvoort, Crystal; Jadrich, James

    2009-01-01

    Conceptually, students are typically introduced to light as a type of wave. However, children struggle to understand this model because it is highly abstract. Light can be represented more concretely using the photon model. According to this scientific model, light emanates from sources as tiny "packets" of energy (called "photons") that move in…

  10. Light metals 1989

    SciTech Connect

    Campbell, P.G.

    1989-01-01

    This volume contains a cross section of the most important developments in the light metals field. The papers detail the latest solutions to problems in alumina and bauxite; carbon technology; cast shop technology; reduction technology; and reactive metals. Nearly every important company and research facility in the aluminum industry is represented. Light Metals 1989 is a reference for anyone in light metals technology.

  11. Simulating Supernova Light Curves

    SciTech Connect

    Even, Wesley Paul; Dolence, Joshua C.

    2016-05-05

    This report discusses supernova light simulations. A brief review of supernovae, basics of supernova light curves, simulation tools used at LANL, and supernova results are included. Further, it happens that many of the same methods used to generate simulated supernova light curves can also be used to model the emission from fireballs generated by explosions in the earth’s atmosphere.

  12. New Light for Phytochemicals.

    PubMed

    Holopainen, Jarmo K; Kivimäenpää, Minna; Julkunen-Tiitto, Riitta

    2017-09-19

    Light-emitting diode (LED) lighting technology with narrow-bandwidth illumination helps to reduce energy consumption on covered crops. Here, we discuss how this new technology, which provides flexible modification of light spectra, will open new avenues for natural modulation of medicinal and crop plant metabolomes for better colour, flavour, fragrance, and antioxidant properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. CSM/LM Lighting

    NASA Technical Reports Server (NTRS)

    Interbartolo, Michael

    2009-01-01

    Objectives include: a)Identify the types and uses of the various lighting components: Interior (CM, LM), Exterior (CSM, LM); b) Explain the purpose and locations of electroluminescent (EL) and radioluminescent (RL)lighting techniques; c) Understand the use of various D&C lighting components; and d) Understand in-flight anomalies.

  14. Architectural Physics: Lighting.

    ERIC Educational Resources Information Center

    Hopkinson, R. G.

    The author coordinates the many diverse branches of knowledge which have dealt with the field of lighting--physiology, psychology, engineering, physics, and architectural design. Part I, "The Elements of Architectural Physics", discusses the physiological aspects of lighting, visual performance, lighting design, calculations and measurements of…

  15. Plant Light Measurement & Calculations.

    ERIC Educational Resources Information Center

    Hershey, David R.

    1991-01-01

    The differences between measuring light intensity for the human eye and for plant photosynthesis are discussed. Conversion factors needed to convert various units of light are provided. Photosynthetic efficiency and the electricity costs for plants to undergo photosynthesis using interior lighting are described. (KR)

  16. Getting Pool Light Right.

    ERIC Educational Resources Information Center

    Hunsaker, Scot

    1998-01-01

    Examines the use of lighting, both artificial and natural, that can enhance the aesthetic quality and functionality of areas with indoor swimming pools. Discusses glare and shadow-reduction measures that aid competitive events, including lighting above and below water levels, and highlights lighting issues during televised events. Descriptions of…

  17. Light in man's environment

    PubMed Central

    Marshall, J

    2016-01-01

    Light in the form of solar radiation influenced early civilisations and resulted in the independent development of a number of sun-worshipping dieties. These were of particular importance as hunter gatherers transformed into settled agricultural societies. All artificial light sources were synonymous with fire, and early civilisations began to expand their visual day by burning brands, oil, and candles. Fire-based light sources extended for thousands of years and were still present in the era of gas lighting. Light meant fire risk. The advent of incandescent bulbs and the era of electric lighting really only expanded in the early part of the twentieth century. Fluorescent lighting became available in the 1940s, and today the drive for low energy has resulted in a plethora of novel light sources—in particular, light-emitting diodes (LEDs). Evolution governed the development of the eye in relation to roughly 12 h of light gradually changing to 12 h of darkness. Today almost daylight levels can be achieved abruptly at the flick of a switch. Many studies have demonstrated the spectral dependence of eye health, with the retinal hazard zone associated with wavelengths in the blue, peaking at 441 nm— many of today's low-energy sources peak in this region. Given the increased longevity and artificial light sources emitting at biologically unfriendly wavelengths, attention has to be directed towards light in man's environment as a risk factor in age-related ocular diseases. PMID:26742864

  18. Emergency lighting gets 'smarter'.

    PubMed

    Daniels, Alan

    2012-10-01

    Alan Daniels, business development director of emergency lighting specialist, P4, describes the latest trends in, and requirements for, emergency lighting, a vital part of the building services footprint in hospitals and other healthcare premises. He also explains how those responsible for the safe operation of emergency lighting system can ensure they comply with their obligations under the law.

  19. Light in man's environment.

    PubMed

    Marshall, J

    2016-02-01

    Light in the form of solar radiation influenced early civilisations and resulted in the independent development of a number of sun-worshipping dieties. These were of particular importance as hunter gatherers transformed into settled agricultural societies. All artificial light sources were synonymous with fire, and early civilisations began to expand their visual day by burning brands, oil, and candles. Fire-based light sources extended for thousands of years and were still present in the era of gas lighting. Light meant fire risk. The advent of incandescent bulbs and the era of electric lighting really only expanded in the early part of the twentieth century. Fluorescent lighting became available in the 1940s, and today the drive for low energy has resulted in a plethora of novel light sources-in particular, light-emitting diodes (LEDs). Evolution governed the development of the eye in relation to roughly 12 h of light gradually changing to 12 h of darkness. Today almost daylight levels can be achieved abruptly at the flick of a switch. Many studies have demonstrated the spectral dependence of eye health, with the retinal hazard zone associated with wavelengths in the blue, peaking at 441 nm- many of today's low-energy sources peak in this region. Given the increased longevity and artificial light sources emitting at biologically unfriendly wavelengths, attention has to be directed towards light in man's environment as a risk factor in age-related ocular diseases.

  20. Changes in light quality alter physiological responses of soybean to thiamethoxam.

    PubMed

    Kim, Hae Won; Amirsadeghi, Sasan; McKenzie-Gopsill, Andrew; Afifi, Maha; Bozzo, Gale; Lee, Elizabeth A; Lukens, Lewis; Swanton, Clarence J

    2016-09-01

    The interaction between neighboring weed-induced far-red enriched light and thiamethoxam can significantly alter soybean seedling morphology, nodulation, isoflavone levels, UV-absorbing phenolics, and carbon and nitrogen content. Neonicotinoid insecticides that are widely used on major crop plants can enhance plant growth and yield. Although the underlying mechanism of this enhanced growth and yield is not clear, recent studies suggest that neonicotinoids such as thiamethoxam (TMX) may exert their effects at least in part via signals that involve salicylic acid (SA) and jasmonic acid (JA). In the current research, effects of TMX on morphological and physiological responses of soybean have been compared under far-red-depleted (FR-D) and far-red-enriched (FR-E) light reflected by neighboring weeds. TMX significantly enhanced shoot and root growth but did not prevent stem elongation under FR-E light. Also, TMX did not prevent reductions in shoot carbon content and shoot carbon to nitrogen ratio under FR-E light. Despite similarities between these TMX effects in soybean and those known for SA and JA in other plant species, TMX significantly enhanced root-nodule numbers per plant and levels of root isoflavones malonyl-daidzin and malonyl-genistin under FR-E light only. These results suggest that the combined effect of FR-E light and TMX triggers a mechanism that operates concomitantly to enhance root isoflavones and nodulation in soybean.

  1. Light On the Behavior of Light Bulbs.

    ERIC Educational Resources Information Center

    Armstrong, H. L.

    1985-01-01

    Discusses a problem (on page 523 of "College Physics," by Sears, Zemansky, and Young, published by Addison-Wesley, 1980) concerning light bulbs and resistance. Shows why the assumption of constant resistance is unrealistic and provides guidelines for revision. (DH)

  2. Light On the Behavior of Light Bulbs.

    ERIC Educational Resources Information Center

    Armstrong, H. L.

    1985-01-01

    Discusses a problem (on page 523 of "College Physics," by Sears, Zemansky, and Young, published by Addison-Wesley, 1980) concerning light bulbs and resistance. Shows why the assumption of constant resistance is unrealistic and provides guidelines for revision. (DH)

  3. PP2C-like Promoter and Its Deletion Variants Are Induced by ABA but Not by MeJA and SA in Arabidopsis thaliana.

    PubMed

    Bhalothia, Purva; Sangwan, Chetna; Alok, Anshu; Mehrotra, Sandhya; Mehrotra, Rajesh

    2016-01-01

    Gene expression is mediated through interaction between cis regulatory elements and its cognate transcription factors. Cis regulatory elements are defined as non-coding DNA sequences that provide the binding sites for transcription factors and are clustered in the upstream region of genes. ACGT cis regulatory element is one of the important cis regulatory elements found to be involved in diverse biological processes like auxin response, salicylic acid (SA) response, UV light response, ABA response and jasmonic acid (JA) response. We identified through in silico analysis that the upstream region of protein phosphatase 2C (PP2C) gene has a distinct genetic architecture of ACGT elements. In the present study, the activation of the full length promoter and its deletion constructs like 900 base pair, 500 base pair, 400 base pair and NRM (Nathji Rajesh Mehrotra) were examined by stable transformation in Arabidopsis thaliana using β-glucuronidase as the reporter gene. Evaluation of deletion constructs of PP2C-like promoter was carried out in the presence of phytohormones like abscisic acid (ABA), SA and JA. Our result indicated that the full length and 900 base pair promoter-reporter constructs of PP2C-like promoter was induced in response to ABA but not to methyl jasmonate and SA.

  4. High Intensity Lights

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Xenon arc lamps developed during the Apollo program by Streamlight, Inc. are the basis for commercial flashlights and emergency handlights. These are some of the brightest portable lights made. They throw a light some 50 times brighter than automobile high beams and are primarily used by police and military. The light penetrates fog and smoke and returns less back-scatter light. They are operated on portable power packs as boat and auto batteries. An infrared model produces totally invisible light for covert surveillance.

  5. Light-storing photocatalyst

    SciTech Connect

    Zhang Junying; Pan Feng; Hao Weichang; Ge Qi; Wang Tianmian

    2004-12-06

    Light-storing photocatalyst was prepared by coating light-storing phosphor and TiO{sub 2} photocatalyst in sequence on ceramic. The light-storing photocatalyst can store light irradiation and emit slowly. Consequently, the photocatalyst remains active when the irradiation source is cut off. Rhodamine B (RhB) can be decomposed efficiently by this photocatalyst in the dark after it absorbs light irradiation. This photocatalyst is photoreactive in an outdoor environment or can save energy by supplying irradiation intermittently for the photocatalyst.

  6. Astronomy and Sodium Lighting,

    DTIC Science & Technology

    1984-02-01

    o-... 0 -23- rincreased Oxygen Atoms , Soodum Oxygen Atoms Peckg trom LPS Ligh t Level Limit Motel Br-ue Green...Yellow Orcrge Red Fig. 5 - San Jose 1979 with bPS street lights New Sodium Peaks frome Oxyge.n Atom’s HPS Oxygen Atoms Full Growth Light Level- 1990...Light LevelI 1979 Light Level I L Light Level - 0 Lmt Broad Specr ,,m Excess Li;hl SVoel Blue Gpen Yelloo Oro-’e Red Fig. 6 -- Sarn Jose with 11PS street

  7. Roadmap on structured light

    NASA Astrophysics Data System (ADS)

    Rubinsztein-Dunlop, Halina; Forbes, Andrew; Berry, M. V.; Dennis, M. R.; Andrews, David L.; Mansuripur, Masud; Denz, Cornelia; Alpmann, Christina; Banzer, Peter; Bauer, Thomas; Karimi, Ebrahim; Marrucci, Lorenzo; Padgett, Miles; Ritsch-Marte, Monika; Litchinitser, Natalia M.; Bigelow, Nicholas P.; Rosales-Guzmán, C.; Belmonte, A.; Torres, J. P.; Neely, Tyler W.; Baker, Mark; Gordon, Reuven; Stilgoe, Alexander B.; Romero, Jacquiline; White, Andrew G.; Fickler, Robert; Willner, Alan E.; Xie, Guodong; McMorran, Benjamin; Weiner, Andrew M.

    2017-01-01

    Structured light refers to the generation and application of custom light fields. As the tools and technology to create and detect structured light have evolved, steadily the applications have begun to emerge. This roadmap touches on the key fields within structured light from the perspective of experts in those areas, providing insight into the current state and the challenges their respective fields face. Collectively the roadmap outlines the venerable nature of structured light research and the exciting prospects for the future that are yet to be realized.

  8. Extending MAM5 Meta-Model and JaCalIV E Framework to Integrate Smart Devices from Real Environments

    PubMed Central

    2016-01-01

    This paper presents the extension of a meta-model (MAM5) and a framework based on the model (JaCalIVE) for developing intelligent virtual environments. The goal of this extension is to develop augmented mirror worlds that represent a real and virtual world coupled, so that the virtual world not only reflects the real one, but also complements it. A new component called a smart resource artifact, that enables modelling and developing devices to access the real physical world, and a human in the loop agent to place a human in the system have been included in the meta-model and framework. The proposed extension of MAM5 has been tested by simulating a light control system where agents can access both virtual and real sensor/actuators through the smart resources developed. The results show that the use of real environment interactive elements (smart resource artifacts) in agent-based simulations allows to minimize the error between simulated and real system. PMID:26926691

  9. Extending MAM5 Meta-Model and JaCalIV E Framework to Integrate Smart Devices from Real Environments.

    PubMed

    Rincon, J A; Poza-Lujan, Jose-Luis; Julian, V; Posadas-Yagüe, Juan-Luis; Carrascosa, C

    2016-01-01

    This paper presents the extension of a meta-model (MAM5) and a framework based on the model (JaCalIVE) for developing intelligent virtual environments. The goal of this extension is to develop augmented mirror worlds that represent a real and virtual world coupled, so that the virtual world not only reflects the real one, but also complements it. A new component called a smart resource artifact, that enables modelling and developing devices to access the real physical world, and a human in the loop agent to place a human in the system have been included in the meta-model and framework. The proposed extension of MAM5 has been tested by simulating a light control system where agents can access both virtual and real sensor/actuators through the smart resources developed. The results show that the use of real environment interactive elements (smart resource artifacts) in agent-based simulations allows to minimize the error between simulated and real system.

  10. Light Emitting Diode (LED)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A special lighting technology was developed for space-based commercial plant growth research on NASA's Space Shuttle. Surgeons have used this technology to treat brain cancer on Earth, in two successful operations. The treatment technique called photodynamic therapy, requires the surgeon to use tiny pinhead-size Light Emitting Diodes (LEDs) (a source releasing long wavelengths of light) to activate light-sensitive, tumor-treating drugs. Laser light has been used for this type of surgery in the past, but the LED light illuminates through all nearby tissues, reaching parts of a tumor that shorter wavelengths of laser light carnot. The new probe is safer because the longer wavelengths of light are cooler than the shorter wavelengths of laser light, making the LED less likely to injure normal brain tissue near the tumor. It can also be used for hours at a time while still remaining cool to the touch. The LED probe consists of 144 tiny pinhead-size diodes, is 9-inches long, and about one-half-inch in diameter. The small balloon aids in even distribution of the light source. The LED light source is compact, about the size of a briefcase, and can be purchased for a fraction of the cost of a laser. The probe was developed for photodynamic cancer therapy by the Marshall Space Flight Center under a NASA Small Business Innovative Research program grant.

  11. Light Emitting Diode (LED)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A special lighting technology was developed for space-based commercial plant growth research on NASA's Space Shuttle. Surgeons have used this technology to treat brain cancer on Earth, in two successful operations. The treatment technique called photodynamic therapy, requires the surgeon to use tiny pinhead-size Light Emitting Diodes (LEDs) (a source releasing long wavelengths of light) to activate light-sensitive, tumor-treating drugs. Laser light has been used for this type of surgery in the past, but the LED light illuminates through all nearby tissues, reaching parts of a tumor that shorter wavelengths of laser light carnot. The new probe is safer because the longer wavelengths of light are cooler than the shorter wavelengths of laser light, making the LED less likely to injure normal brain tissue near the tumor. It can also be used for hours at a time while still remaining cool to the touch. The LED probe consists of 144 tiny pinhead-size diodes, is 9-inches long, and about one-half-inch in diameter. The small balloon aids in even distribution of the light source. The LED light source is compact, about the size of a briefcase, and can be purchased for a fraction of the cost of a laser. The probe was developed for photodynamic cancer therapy by the Marshall Space Flight Center under a NASA Small Business Innovative Research program grant.

  12. Gravity slows light

    NASA Astrophysics Data System (ADS)

    O'Sullivan, Ian

    2014-03-01

    The speed of light is measured as a constant number of metres per second. However, a meter is a measure of how far light travels in a second. That is, light always travels as far as it does in a second every second. This is a circular definition. When measured against other things, light speed must change. Gravity is usually described as a consequence of a curve in spacetime. The word ``space'' has two distinct meanings. In geometry, space is a continuous area. In relativity, ``space'' refers exclusively to geometric spaces measured with light. ``Time'' in a relativistic sense also refers exclusively to the passage of time as measured against light. So a curve in spacetime (a relativistic concept) is a gradual deviation in the thing we use to measure geometric spaces and the passage of time, i.e. the speed of light. I show how Newtonian gravity can explain observable phenomena if the speed of light is inversely proportional to the strength of the gravitational field. For example, we would also expect light to refract as it changes speed passing near massive bodies. Boundary conditions are also discussed, for example, very high gravity will slow light to a stop, making it impossible to measure anything against light, giving a gravitational singularity.

  13. Photonic crystal light source

    DOEpatents

    Fleming, James G [Albuquerque, NM; Lin, Shawn-Yu [Albuquerque, NM; Bur, James A [Corrales, NM

    2004-07-27

    A light source is provided by a photonic crystal having an enhanced photonic density-of-states over a band of frequencies and wherein at least one of the dielectric materials of the photonic crystal has a complex dielectric constant, thereby producing enhanced light emission at the band of frequencies when the photonic crystal is heated. The dielectric material can be a metal, such as tungsten. The spectral properties of the light source can be easily tuned by modification of the photonic crystal structure and materials. The photonic crystal light source can be heated electrically or other heating means. The light source can further include additional photonic crystals that exhibit enhanced light emission at a different band of frequencies to provide for color mixing. The photonic crystal light source may have applications in optical telecommunications, information displays, energy conversion, sensors, and other optical applications.

  14. Navigation lights color study

    NASA Astrophysics Data System (ADS)

    Barbosa, Jose G.; Alberg, Matthew T.

    2015-05-01

    The chromaticity of navigation lights are defined by areas on the International Commission on Illumination (CIE) 1931 chromaticity diagram. The corner coordinates for these areas are specified in the International Regulations for Prevention of Collisions at Sea, 1972 (72 COLREGS). The navigation light's color of white, red, green, and yellow are bounded by these areas. The chromaticity values specified by the COLREGS for navigation lights were intended for the human visual system (HVS). The HVS can determine the colors of these lights easily under various conditions. For digital color camera imaging systems the colors of these lights are dependent on the camera's color spectral sensitivity, settings, and color correction. At night the color of these lights are used to quickly determine the relative course of vessels. If these lights are incorrectly identified or there is a delay in identifying them this could be a potential safety of ship concern. Vessels that use camera imaging systems exclusively for sight, at night, need to detect, identify, and discriminate navigation lights for navigation and collision avoidance. The introduction of light emitting diode (LED) lights and lights with different spectral signatures have the potential to be imaged very differently with an RGB color filter array (CFA) color camera than with the human eye. It has been found that some green navigation lights' images appear blue verse green. This has an impact on vessels that use camera imaging systems exclusively for navigation. This paper will characterize color cameras ability to properly reproducing navigation lights' color and survey a set of navigation light to determine if they conform to the COLREGS.

  15. Dermal sensitization potential of ja-2 solid propellant in guinea pigs. Report for 4 April-9 May 1986

    SciTech Connect

    Lewis, C.M.; Brown, L.D.; Korte, D.W.

    1989-11-01

    JA-2 Solid Propellant was evaluated for its potential to produce dermal sensitization in male guinea pigs. The Buehler test, which utilizes repeated closed patch inductions with the test compound, was used for this evaluation. No evidence that JA-2 Solid Propellant induced sensitization was obtained in the study.

  16. Studying Light Color using White LED Lighting

    NASA Astrophysics Data System (ADS)

    Yamagishi, Misako; Yamaba, Kazuo; Nagata, Manori; Kubo, Chiho; Nokura, Kunihiro

    Recently, white Light Emitting Diodes (LEDs) are receiving attention worldwide as new lighting devices. This study examined effects of a lighting application on performance using white LEDs. The light color—the correlated color temperature (CCT) —was assessed. It affected to psychological states and physiological conditions. Three CCT conditions were respectively set for the experiment: 2500 K, 5000 K, and 8200 K. In all, 20 younger subjects (20-30 years old), 15 middle-aged to elderly subjects (45-60 years old) and 12 elderly subjects (over 65 years-old) participated. They were presented a Numerical Verification (NV) task for performance measurement. The psychological states on performance were evaluated using the lighting assessment questionnaire. The physiological conditions were recorded using an electrocardiograph. Results show that the effects of CCT differ among age groups. Especially, the performance of younger subjects might differ from CCT conditions; elderly subjects are affected by CCT condition because of their visual acuity or response to contrast of objects.

  17. Light Emitting Diodes (LEDs)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A special lighting technology was developed for space-based commercial plant growth research on NASA's Space Shuttle. Surgeons have used this technology to treat brain cancer on Earth, in two successful operations. The treatment technique, called Photodynamic Therapy, requires the surgeon to use tiny, pinhead-size Light Emitting Diodes (LEDs) (a source that releases long wavelengths of light ) to activate light-sensitive, tumor-treating drugs. 'A young woman operated on in May 1999 has fully recovered with no complications and no evidence of the tumor coming back,' said Dr. Harry Whelan, a pediatric neurologist at the Medical Hospital of Wisconsin in Milwaukee. Laser light has been used for this type of surgery in the past, but the LED light illuminates through all nearby tissues, reaching parts of a tumor that shorter wavelengths of laser light carnot. The new probe is safer because the longer wavelengths of light are cooler than the shorter wavelengths of laser light, making the LED less likely to injure normal brain tissue near the tumor. It can be used for hours at a time while still remaining cool to the touch. The LED light source is compact, about the size of a briefcase, and can be purchased for a fraction of the cost of a laser. The LEDs, developed and managed by NASA's Marshall Space Flight Center, have been used on seven Space Shuttle flights inside the Microgravity Astroculture Facility. This technology has also been successfully used to further commercial research in crop growth.

  18. Light-adjustable lens.

    PubMed Central

    Schwartz, Daniel M

    2003-01-01

    PURPOSE: First, to determine whether a silicone light-adjustable intraocular lens (IOL) can be fabricated and adjusted precisely with a light delivery device (LDD). Second, to determine the biocompatibility of an adjustable IOL and whether the lens can be adjusted precisely in vivo. METHODS: After fabrication of a light-adjustable silicone formulation, IOLs were made and tested in vitro for cytotoxicity, leaching, precision of adjustment, optical quality after adjustment, and mechanical properties. Light-adjustable IOLs were then tested in vivo for biocompatibility and precision of adjustment in a rabbit model. In collaboration with Zeiss-Meditec, a digital LDD was developed and tested to correct for higher-order aberrations in light-adjustable IOLs. RESULTS: The results establish that a biocompatible silicone IOL can be fabricated and adjusted using safe levels of light. There was no evidence of cytotoxicity or leaching. Testing of mechanical properties revealed no significant differences from commercial controls. Implantation of light-adjustable lenses in rabbits demonstrated- excellent biocompatibility after 6 months, comparable to a commercially available IOL. In vivo spherical (hyperopic and myopic) adjustment in rabbits was achieved using an analog light delivery system. The digital light delivery system was tested and achieved correction of higher-order aberrations. CONCLUSION: A silicone light-adjustable IOL and LDD have been developed to enable postoperative, noninvasive adjustment of lens power. The ability to correct higher-order aberrations in these materials has broad potential applicability for optimization of vision in patients undergoing cataract and refractive surgery. PMID:14971588

  19. Light Emitting Diodes (LEDs)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A special lighting technology was developed for space-based commercial plant growth research on NASA's Space Shuttle. Surgeons have used this technology to treat brain cancer on Earth, in two successful operations. The treatment technique, called Photodynamic Therapy, requires the surgeon to use tiny, pinhead-size Light Emitting Diodes (LEDs) (a source that releases long wavelengths of light ) to activate light-sensitive, tumor-treating drugs. 'A young woman operated on in May 1999 has fully recovered with no complications and no evidence of the tumor coming back,' said Dr. Harry Whelan, a pediatric neurologist at the Medical Hospital of Wisconsin in Milwaukee. Laser light has been used for this type of surgery in the past, but the LED light illuminates through all nearby tissues, reaching parts of a tumor that shorter wavelengths of laser light carnot. The new probe is safer because the longer wavelengths of light are cooler than the shorter wavelengths of laser light, making the LED less likely to injure normal brain tissue near the tumor. It can be used for hours at a time while still remaining cool to the touch. The LED light source is compact, about the size of a briefcase, and can be purchased for a fraction of the cost of a laser. The LEDs, developed and managed by NASA's Marshall Space Flight Center, have been used on seven Space Shuttle flights inside the Microgravity Astroculture Facility. This technology has also been successfully used to further commercial research in crop growth.

  20. Integrated metabolomic and proteomic analysis reveals systemic responses of Rubrivivax benzoatilyticus JA2 to aniline stress.

    PubMed

    Mujahid, Md; Prasuna, M Lakshmi; Sasikala, Ch; Ramana, Ch Venkata

    2015-02-06

    Aromatic amines are widely distributed in the environment and are major environmental pollutants. Although degradation of aromatic amines is well studied in bacteria, physiological adaptations and stress response to these toxic compounds is not yet fully understood. In the present study, systemic responses of Rubrivivax benzoatilyticus JA2 to aniline stress were deciphered using metabolite and iTRAQ-labeled protein profiling. Strain JA2 tolerated high concentrations of aniline (30 mM) with trace amounts of aniline being transformed to acetanilide. GC-MS metabolite profiling revealed aniline stress phenotype wherein amino acid, carbohydrate, fatty acid, nitrogen metabolisms, and TCA (tricarboxylic acid cycle) were modulated. Strain JA2 responded to aniline by remodeling the proteome, and cellular functions, such as signaling, transcription, translation, stress tolerance, transport and carbohydrate metabolism, were highly modulated. Key adaptive responses, such as transcription/translational changes, molecular chaperones to control protein folding, and efflux pumps implicated in solvent extrusion, were induced in response to aniline stress. Proteo-metabolomics indicated extensive rewiring of metabolism to aniline. TCA cycle and amino acid catabolism were down-regulated while gluconeogenesis and pentose phosphate pathways were up-regulated, leading to the synthesis of extracellular polymeric substances. Furthermore, increased saturated fatty acid ratios in membranes due to aniline stress suggest membrane adaptation. The present study thus indicates that strain JA2 employs multilayered responses: stress response, toxic compound tolerance, energy conservation, and metabolic rearrangements to aniline.

  1. Transcriptome Analysis in Haematococcus pluvialis: Astaxanthin Induction by Salicylic Acid (SA) and Jasmonic Acid (JA).

    PubMed

    Gao, Zhengquan; Li, Yan; Wu, Guanxun; Li, Guoqiang; Sun, Haifeng; Deng, Suzhen; Shen, Yicheng; Chen, Guoqiang; Zhang, Ruihao; Meng, Chunxiao; Zhang, Xiaowen

    2015-01-01

    Haematococcus pluvialis is an astaxanthin-rich microalga that can increase its astaxanthin production by salicylic acid (SA) or jasmonic acid (JA) induction. The genetic transcriptome details of astaxanthin biosynthesis were analyzed by exposing the algal cells to 25 mg/L of SA and JA for 1, 6 and 24 hours, plus to the control (no stress). Based on the RNA-seq analysis, 56,077 unigenes (51.7%) were identified with functions in response to the hormone stress. The top five identified subcategories were cell, cellular process, intracellular, catalytic activity and cytoplasm, which possessed 5600 (~9.99%), 5302 (~9.45%), 5242 (~9.35%), 4407 (~7.86%) and 4195 (~7.48%) unigenes, respectively. Furthermore, 59 unigenes were identified and assigned to 26 putative transcription factors (TFs), including 12 plant-specific TFs. They were likely associated with astaxanthin biosynthesis in Haematococcus upon SA and JA stress. In comparison, the up-regulation of differential expressed genes occurred much earlier, with higher transcript levels in the JA treatment (about 6 h later) than in the SA treatment (beyond 24 h). These results provide valuable information for directing metabolic engineering efforts to improve astaxanthin biosynthesis in H. pluvialis.

  2. Light metal production

    DOEpatents

    Fan, Qinbai

    2016-04-19

    An electrochemical process for the production of light metals, particularly aluminum. Such a process involves contacting a light metal source material with an inorganic acid to form a solution containing the light metal ions in high concentration. The solution is fed to an electrochemical reactor assembly having an anode side containing an anode and a cathode side containing a cathode, with anode side and the cathode side separated by a bipolar membrane, with the solution being fed to the anode side. Light metal ions are electrochemically transferred through the bipolar membrane to the cathode side. The process further involves reducing the light metal ions to light metal powder. An associated processing system is also provided.

  3. Lighting technology atlas

    SciTech Connect

    1994-12-31

    This Atlas is a comprehensive guide to energy efficient lighting, covering both design and technology fundamentals. It presents a ``systems approach`` to lighting design, and characterizes the existing stock of lighting technology, with descriptions of available and emerging energy efficient alternatives. Technologies covered include incandescent, fluorescent, and HID lighting systems, along with daylighting, controls, reflectors, and specialty products such as exit signs and traffic signals. Market trends and the energy impact of lighting are detailed, as well as implementation issues such as economics, maintenance, and the environmental impacts of lamp and ballast recycling. The Atlas also offers practical tips for lighting installers and facility personnel, as well as a resource section with extensive product lists, a guide to available software, and a glossary.

  4. The Magic of Lighting Maintenance

    ERIC Educational Resources Information Center

    Modern Schools, 1973

    1973-01-01

    A well-planned lighting maintenance program can provide more light for your money, better appearance of the lighting system, lower overall cost of light, and fewer accidents and better visibility for users of the school. (Author)

  5. Partial Activation of SA- and JA-Defensive Pathways in Strawberry upon Colletotrichum acutatum Interaction

    PubMed Central

    Amil-Ruiz, Francisco; Garrido-Gala, José; Gadea, José; Blanco-Portales, Rosario; Muñoz-Mérida, Antonio; Trelles, Oswaldo; de los Santos, Berta; Arroyo, Francisco T.; Aguado-Puig, Ana; Romero, Fernando; Mercado, José-Ángel; Pliego-Alfaro, Fernando; Muñoz-Blanco, Juan; Caballero, José L.

    2016-01-01

    Understanding the nature of pathogen host interaction may help improve strawberry (Fragaria × ananassa) cultivars. Plant resistance to pathogenic agents usually operates through a complex network of defense mechanisms mediated by a diverse array of signaling molecules. In strawberry, resistance to a variety of pathogens has been reported to be mostly polygenic and quantitatively inherited, making it difficult to associate molecular markers with disease resistance genes. Colletotrichum acutatum spp. is a major strawberry pathogen, and completely resistant cultivars have not been reported. Moreover, strawberry defense network components and mechanisms remain largely unknown and poorly understood. Assessment of the strawberry response to C. acutatum included a global transcript analysis, and acidic hormones SA and JA measurements were analyzed after challenge with the pathogen. Induction of transcripts corresponding to the SA and JA signaling pathways and key genes controlling major steps within these defense pathways was detected. Accordingly, SA and JA accumulated in strawberry after infection. Contrastingly, induction of several important SA, JA, and oxidative stress-responsive defense genes, including FaPR1-1, FaLOX2, FaJAR1, FaPDF1, and FaGST1, was not detected, which suggests that specific branches in these defense pathways (those leading to FaPR1-2, FaPR2-1, FaPR2-2, FaAOS, FaPR5, and FaPR10) were activated. Our results reveal that specific aspects in SA and JA dependent signaling pathways are activated in strawberry upon interaction with C. acutatum. Certain described defense-associated transcripts related to these two known signaling pathways do not increase in abundance following infection. This finding suggests new insight into a specific putative molecular strategy for defense against this pathogen. PMID:27471515

  6. Partial Activation of SA- and JA-Defensive Pathways in Strawberry upon Colletotrichum acutatum Interaction.

    PubMed

    Amil-Ruiz, Francisco; Garrido-Gala, José; Gadea, José; Blanco-Portales, Rosario; Muñoz-Mérida, Antonio; Trelles, Oswaldo; de Los Santos, Berta; Arroyo, Francisco T; Aguado-Puig, Ana; Romero, Fernando; Mercado, José-Ángel; Pliego-Alfaro, Fernando; Muñoz-Blanco, Juan; Caballero, José L

    2016-01-01

    Understanding the nature of pathogen host interaction may help improve strawberry (Fragaria × ananassa) cultivars. Plant resistance to pathogenic agents usually operates through a complex network of defense mechanisms mediated by a diverse array of signaling molecules. In strawberry, resistance to a variety of pathogens has been reported to be mostly polygenic and quantitatively inherited, making it difficult to associate molecular markers with disease resistance genes. Colletotrichum acutatum spp. is a major strawberry pathogen, and completely resistant cultivars have not been reported. Moreover, strawberry defense network components and mechanisms remain largely unknown and poorly understood. Assessment of the strawberry response to C. acutatum included a global transcript analysis, and acidic hormones SA and JA measurements were analyzed after challenge with the pathogen. Induction of transcripts corresponding to the SA and JA signaling pathways and key genes controlling major steps within these defense pathways was detected. Accordingly, SA and JA accumulated in strawberry after infection. Contrastingly, induction of several important SA, JA, and oxidative stress-responsive defense genes, including FaPR1-1, FaLOX2, FaJAR1, FaPDF1, and FaGST1, was not detected, which suggests that specific branches in these defense pathways (those leading to FaPR1-2, FaPR2-1, FaPR2-2, FaAOS, FaPR5, and FaPR10) were activated. Our results reveal that specific aspects in SA and JA dependent signaling pathways are activated in strawberry upon interaction with C. acutatum. Certain described defense-associated transcripts related to these two known signaling pathways do not increase in abundance following infection. This finding suggests new insight into a specific putative molecular strategy for defense against this pathogen.

  7. National Synchrotron Light Source

    ScienceCinema

    BNL

    2016-07-12

    A tour of Brookhaven's National Synchrotron Light Source (NSLS), hosted by Associate Laboratory Director for Light Sources, Stephen Dierker. The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviolet, and x-ray light for basic and applied research in physics, chemistry, medicine, geophysics, environmental, and materials sciences.

  8. High efficiency incandescent lighting

    SciTech Connect

    Bermel, Peter; Ilic, Ognjen; Chan, Walker R.; Musabeyoglu, Ahmet; Cukierman, Aviv Ruben; Harradon, Michael Robert; Celanovic, Ivan; Soljacic, Marin

    2014-09-02

    Incandescent lighting structure. The structure includes a thermal emitter that can, but does not have to, include a first photonic crystal on its surface to tailor thermal emission coupled to, in a high-view-factor geometry, a second photonic filter selected to reflect infrared radiation back to the emitter while passing visible light. This structure is highly efficient as compared to standard incandescent light bulbs.

  9. Berkeley Lighting Cone

    SciTech Connect

    Lask, Kathleen; Gadgil, Ashok

    2016-10-24

    A lighting cone is a simple metal cone placed on the fuel bed of a stove during ignition to act as a chimney, increasing the draft through the fuel bed. Many stoves tend to be difficult to light due to poor draft through the fuel bed, so lighting cones are used in various parts of the world as an inexpensive accessory to help with ignition.

  10. Slow and Fast Light

    DTIC Science & Technology

    2001-09-24

    25) where λ is the vacuum wavelength of the radiation. Recent demonstrations of slow light have been enabled by nonlinear optical techniques which can...typical procedure for producing slow light is to make use of electromagnetically induced transparency (EIT), a technique introduced by Harris, Field and... Slow ” and “Fast” Light Robert W. Boyd The Institute of Optics University of Rochester Rochester, New York 14627 USA Daniel J. Gauthier Department of

  11. Photosynthetic Light-Harvesting

    NASA Astrophysics Data System (ADS)

    Pullerits, T.; Polivka, T.; Sundström, V.

    Photosynthetic organisms utilize (bacterio) chlorophylls and carotenoids as main light-harvesting pigments. In this chapter, we review bacteriochlorophyll light-harvesting in photosynthetic purple bacteria; we discuss intra- and intercomplex energy transfer processes as well as energy trapping by reaction centers. From the viewpoint of light-harvesting, in most organisms carotenoids are accessory pigments absorbing in the blue-green region of the solar spectrum, where chlorophylls and bacteriochlorophylls have weak absorption. Here, we discuss carotenoid light-harvesting in a pigment-protein complex having carotenoids as main lightharvesting pigment, the peridinin chlorophyll protein (PCP).

  12. Theodolite Ring Lights

    NASA Technical Reports Server (NTRS)

    Clark, David

    2006-01-01

    Theodolite ring lights have been invented to ease a difficulty encountered in the well-established optical-metrology practice of using highly reflective spherical tooling balls as position references. A theodolite ring light produces a more easily visible reflection and eliminates the need for an autocollimating device. A theodolite ring light is a very bright light source that is well centered on the optical axis of the instrument. It can be fabricated, easily and inexpensively, for use on a theodolite or telescope of any diameter.

  13. Dissecting a Light Echo

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on image for audio animation

    This animation illustrates how a light echo works, and how an optical illusion of material moving outward is created.

    A light echo occurs when a star explodes, acting like a cosmic flashbulb. The light from this explosion zips through nearby dust clumps, illuminating and heating them up slightly. This brief period of warming causes them to glow in infrared, like a chain of Christmas bulbs lighting up one by one.

    The animation starts by showing the explosion of a star, which results in a flash of light that moves outward in all directions. The direction of our line of sight from Earth is indicated by the blue arrow.

    When the light flash reaches surrounding dust, shown here as three dark clouds, the dust is heated up, creating infrared light that begins to travel toward Earth (indicated by the red arrows). Dust closest to the explosion lights up first, while the explosion's shock wave takes longer to reach more distant material. This results in light from different parts of the cloud reaching Earth at different times, creating the illusion of motion over time.

    As the animation shows, the inclination of the cloud toward our line of sight can result in the material seeming to move both away from and toward the central star.

  14. Photovoltaic lighting system performance

    SciTech Connect

    Harrington, S.R.; Hund, T.D.

    1996-06-01

    The performance of 21 PV-powered low pressure sodium lighting systems on a multi-use has been documented in this paper. Specific areas for evaluation include the vandal resistant PV modules, constant voltage and on/off PV charge controllers, flooded deep-cycle lead-antimony and valve regulated lead-acid (VLRA) gel batteries, and low pressure sodium ballasts and lights. The PV lighting system maintenance intervals and lessons learned have been documented over the past 2.5 years. The above performance data has shown that with careful hardware selection, installation, and maintenance intervals the PV lighting systems will operate reliably.

  15. Dissecting a Light Echo

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on image for audio animation

    This animation illustrates how a light echo works, and how an optical illusion of material moving outward is created.

    A light echo occurs when a star explodes, acting like a cosmic flashbulb. The light from this explosion zips through nearby dust clumps, illuminating and heating them up slightly. This brief period of warming causes them to glow in infrared, like a chain of Christmas bulbs lighting up one by one.

    The animation starts by showing the explosion of a star, which results in a flash of light that moves outward in all directions. The direction of our line of sight from Earth is indicated by the blue arrow.

    When the light flash reaches surrounding dust, shown here as three dark clouds, the dust is heated up, creating infrared light that begins to travel toward Earth (indicated by the red arrows). Dust closest to the explosion lights up first, while the explosion's shock wave takes longer to reach more distant material. This results in light from different parts of the cloud reaching Earth at different times, creating the illusion of motion over time.

    As the animation shows, the inclination of the cloud toward our line of sight can result in the material seeming to move both away from and toward the central star.

  16. Light source modeling for automotive lighting devices

    NASA Astrophysics Data System (ADS)

    Zerhau-Dreihoefer, Harald; Haack, Uwe; Weber, Thomas; Wendt, Dierk

    2002-08-01

    Automotive lighting devices generally have to meet high standards. For example to avoid discomfort glare for the oncoming traffic, luminous intensities of a low beam headlight must decrease by more than one order of magnitude within a fraction of a degree along the horizontal cutoff-line. At the same time, a comfortable homogeneous illumination of the road requires slowly varying luminous intensities below the cutoff line. All this has to be realized taking into account both, the legal requirements and the customer's stylistic specifications. In order to be able to simulate and optimize devices with a good optical performance different light source models are required. In the early stage of e.g. reflector development simple unstructured models allow a very fast development of the reflectors shape. On the other hand the final simulation of a complex headlamp or signal light requires a sophisticated model of the spectral luminance. In addition to theoretical models based on the light source's geometry, measured luminance data can also be used in the simulation and optimization process.

  17. Light storage with light of arbitrary polarization

    SciTech Connect

    Gao Hong; Rosenberry, Mark; Batelaan, Herman

    2003-05-01

    We have demonstrated the phase coherence of stored light in Rb vapor with a completely optical technique. Combining this technique with polarization measurements provides strong evidence that arbitrary polarizations can be stored. The fidelity obtained exceeds 95% for all polarizations. We view the capability to store polarizations as a first step towards building a quantum memory in such a system.

  18. Creativity essential in lighting design.

    PubMed

    Bayliss, Laura

    2006-01-01

    Laura Bayliss, lighting designer with BDP Lighting, questions the quantitative approach to lighting for healthcare - and makes the case for creative lighting design. This article was originally published in the Institution of Lighting Engineers' The Lighting Journal in summer 2005, after winning the ILE-sponsored "Best Written Paper" in the 2005 Young Lighters Awards.

  19. Natural light illumination system.

    PubMed

    Whang, Allen Jong-Woei; Chen, Yi-Yung; Yang, Shu-Hua; Pan, Po-Hsuan; Chou, Kao-Hsu; Lee, Yu-Chi; Lee, Zong-Yi; Chen, Chi-An; Chen, Cheng-Nan

    2010-12-10

    In recent years, green energy has undergone a lot of development and has been the subject of many applications. Many research studies have focused on illumination with sunlight as a means of saving energy and creating healthy lighting. Natural light illumination systems have collecting, transmitting, and lighting elements. Today, most daylight collectors use dynamic concentrators; these include Sun tracking systems. However, this design is too expensive to be cost effective. To create a low-cost collector that can be easily installed on a large building, we have designed a static concentrator, which is prismatic and cascadable, to collect sunlight for indoor illumination. The transmission component uses a large number of optical fibers. Because optical fibers are expensive, this means that most of the cost for the system will be related to transmission. In this paper, we also use a prismatic structure to design an optical coupler for coupling n to 1. With the n-to-1 coupler, the number of optical fibers necessary can be greatly reduced. Although this new natural light illumination system can effectively guide collected sunlight and send it to the basement or to other indoor places for healthy lighting, previously there has been no way to manage the collected sunlight when lighting was not desired. To solve this problem, we have designed an optical switch and a beam splitter to control and separate the transmitted light. When replacing traditional sources, the lighting should have similar characteristics, such as intensity distribution and geometric parameters, to those of traditional artificial sources. We have designed, simulated, and optimized an illumination lightpipe with a dot pattern to redistribute the collected sunlight from the natural light illumination system such that it equals the qualities of a traditional lighting system. We also provide an active lighting module that provides lighting from the natural light illumination system or LED auxiliary

  20. Light enhances learned fear

    PubMed Central

    Warthen, Daniel M.; Wiltgen, Brian J.; Provencio, Ignacio

    2011-01-01

    The ability to learn, remember, and respond to emotional events is a powerful survival strategy. However, dysregulated behavioral and physiological responses to these memories are maladaptive. To fully understand learned fear and the pathologies that arise during response malfunction we must reveal the environmental variables that influence learned fear responses. Light, a ubiquitous environmental feature, modulates cognition and anxiety. We hypothesized that light modulates responses to learned fear. Using tone-cued fear conditioning, we found that light enhances behavioral responses to learned fear in C57BL/6J mice. Mice in light freeze more in response to a conditioned cue than mice in darkness. The absence of significant freezing during a 2-wk habituation period and during intertrial intervals indicated that light specifically modulates freezing to the learned acoustic cue rather than the context of the experimental chamber. Repeating our assay in two photoreceptor mutant models, Pde6brd1/rd1 and Opn4−/− mice, revealed that light-dependent enhancement of conditioned fear is driven primarily by the rods and/or cones. By repeating our protocol with an altered lighting regimen, we found that lighting conditions acutely modulate responses when altered between conditioning and testing. This is manifested either as an enhancement of freezing when light is added during testing or as a depression of freezing when light is removed during testing. Acute enhancement, but not depression, requires both rod/cone- and melanopsin-dependent photoreception. Our results demonstrate a modulation by light of behavioral responses to learned fear. PMID:21808002

  1. Light enhances learned fear.

    PubMed

    Warthen, Daniel M; Wiltgen, Brian J; Provencio, Ignacio

    2011-08-16

    The ability to learn, remember, and respond to emotional events is a powerful survival strategy. However, dysregulated behavioral and physiological responses to these memories are maladaptive. To fully understand learned fear and the pathologies that arise during response malfunction we must reveal the environmental variables that influence learned fear responses. Light, a ubiquitous environmental feature, modulates cognition and anxiety. We hypothesized that light modulates responses to learned fear. Using tone-cued fear conditioning, we found that light enhances behavioral responses to learned fear in C57BL/6J mice. Mice in light freeze more in response to a conditioned cue than mice in darkness. The absence of significant freezing during a 2-wk habituation period and during intertrial intervals indicated that light specifically modulates freezing to the learned acoustic cue rather than the context of the experimental chamber. Repeating our assay in two photoreceptor mutant models, Pde6b(rd1/rd1) and Opn4(-/-) mice, revealed that light-dependent enhancement of conditioned fear is driven primarily by the rods and/or cones. By repeating our protocol with an altered lighting regimen, we found that lighting conditions acutely modulate responses when altered between conditioning and testing. This is manifested either as an enhancement of freezing when light is added during testing or as a depression of freezing when light is removed during testing. Acute enhancement, but not depression, requires both rod/cone- and melanopsin-dependent photoreception. Our results demonstrate a modulation by light of behavioral responses to learned fear.

  2. Galaxy in Different Lights

    NASA Image and Video Library

    2014-10-08

    The comparison from NASA Hubble telescope and Chandra X-ray Observatory highlights how different the universe can look when viewed in other wavelengths of light. M82 is located 12 million light-years away in the Ursa Major constellation.

  3. The Traffic Light Challenge

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2014-01-01

    Traffic lights are an important part of the transportation infrastructure, regulating traffic flow and maintaining safety when crossing busy streets. When they go awry or become nonfunctional, a great deal of havoc and danger can be present. During power outages, the street lights go out all over the affected area. It would be good to be able to…

  4. Lighting for Education.

    ERIC Educational Resources Information Center

    Ontario Ministry of Colleges and Universities, Toronto.

    Some of the qualities and quantities that must be juggled to produce good lighting for educational facilities are analyzed with photographs, tables, and drawings. The three categories of lamps used for school lighting (incandescent, fluorescent, and high intensity discharge) are described; a lamp selection guide gives the design characteristics of…

  5. Lighting in Architectural Design.

    ERIC Educational Resources Information Center

    Phillips, Derek

    The primary function of this book is to treat the topic of lighting design in such a manner as to bridge the gap between architects and illuminating engineers. The work is divided into three parts: Part I, Principles of Design, offers information and analysis of how natural and artificial lighting affects building design, how illumination levels…

  6. The Traffic Light Challenge

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2014-01-01

    Traffic lights are an important part of the transportation infrastructure, regulating traffic flow and maintaining safety when crossing busy streets. When they go awry or become nonfunctional, a great deal of havoc and danger can be present. During power outages, the street lights go out all over the affected area. It would be good to be able to…

  7. Light-Emitting Pickles

    ERIC Educational Resources Information Center

    Vollmer, M.; Mollmann, K-P.

    2015-01-01

    We present experiments giving new insights into the classical light-emitting pickle experiment. In particular, measurements of the spectra and temperatures, as well as high-speed recordings, reveal that light emission is connected to the polarity of the electrodes and the presence of hydrogen.

  8. Light-Emitting Pickles

    ERIC Educational Resources Information Center

    Vollmer, M.; Mollmann, K-P.

    2015-01-01

    We present experiments giving new insights into the classical light-emitting pickle experiment. In particular, measurements of the spectra and temperatures, as well as high-speed recordings, reveal that light emission is connected to the polarity of the electrodes and the presence of hydrogen.

  9. Light intensity compressor

    DOEpatents

    Rushford, Michael C.

    1990-01-01

    In a system for recording images having vastly differing light intensities over the face of the image, a light intensity compressor is provided that utilizes the properties of twisted nematic liquid crystals to compress the image intensity. A photoconductor or photodiode material that is responsive to the wavelength of radiation being recorded is placed adjacent a layer of twisted nematic liquid crystal material. An electric potential applied to a pair of electrodes that are disposed outside of the liquid crystal/photoconductor arrangement to provide an electric field in the vicinity of the liquid crystal material. The electrodes are substantially transparent to the form of radiation being recorded. A pair of crossed polarizers are provided on opposite sides of the liquid crystal. The front polarizer linearly polarizes the light, while the back polarizer cooperates with the front polarizer and the liquid crystal material to compress the intensity of a viewed scene. Light incident upon the intensity compressor activates the photoconductor in proportion to the intensity of the light, thereby varying the field applied to the liquid crystal. The increased field causes the liquid crystal to have less of a twisting effect on the incident linearly polarized light, which will cause an increased percentage of the light to be absorbed by the back polarizer. The intensity of an image may be compressed by forming an image on the light intensity compressor.

  10. Light intensity compressor

    DOEpatents

    Rushford, Michael C.

    1990-02-06

    In a system for recording images having vastly differing light intensities over the face of the image, a light intensity compressor is provided that utilizes the properties of twisted nematic liquid crystals to compress the image intensity. A photoconductor or photodiode material that is responsive to the wavelength of radiation being recorded is placed adjacent a layer of twisted nematic liquid crystal material. An electric potential applied to a pair of electrodes that are disposed outside of the liquid crystal/photoconductor arrangement to provide an electric field in the vicinity of the liquid crystal material. The electrodes are substantially transparent to the form of radiation being recorded. A pair of crossed polarizers are provided on opposite sides of the liquid crystal. The front polarizer linearly polarizes the light, while the back polarizer cooperates with the front polarizer and the liquid crystal material to compress the intensity of a viewed scene. Light incident upon the intensity compressor activates the photoconductor in proportion to the intensity of the light, thereby varying the field applied to the liquid crystal. The increased field causes the liquid crystal to have less of a twisting effect on the incident linearly polarized light, which will cause an increased percentage of the light to be absorbed by the back polarizer. The intensity of an image may be compressed by forming an image on the light intensity compressor.

  11. Semiconductor Spatial Light Modulators.

    DTIC Science & Technology

    1982-06-01

    16 8 Experimental transmission coefficient in sample garnet ........ ........................ ... 17 9 Typical energy states...laser beam. Carrier lifetime is 4.0 microseconds ............ .... 45 15 Silicon energy band diagram with allowed optical transitions, a) Interband...silicon as a function of 1.06nm light energy ..... ................... .... 62 24 Calculated absorption coefficient in silicon as a function of 1.06n light

  12. Light-emitting Diodes

    PubMed Central

    Opel, Daniel R.; Hagstrom, Erika; Pace, Aaron K.; Sisto, Krisanne; Hirano-Ali, Stefanie A.; Desai, Shraddha

    2015-01-01

    Background: In the early 1990s, the biological significance of light-emitting diodes was realized. Since this discovery, various light sources have been investigated for their cutaneous effects. Study design: A Medline search was performed on light-emitting diode lights and their therapeutic effects between 1996 and 2010. Additionally, an open-label, investigator-blinded study was performed using a yellow light-emitting diode device to treat acne, rosacea, photoaging, alopecia areata, and androgenetic alopecia. Results: The authors identified several case-based reports, small case series, and a few randomized controlled trials evaluating the use of four different wavelengths of light-emitting diodes. These devices were classified as red, blue, yellow, or infrared, and covered a wide range of clinical applications. The 21 patients the authors treated had mixed results regarding patient satisfaction and pre- and post-treatment evaluation of improvement in clinical appearance. Conclusion: Review of the literature revealed that differing wavelengths of light-emitting diode devices have many beneficial effects, including wound healing, acne treatment, sunburn prevention, phototherapy for facial rhytides, and skin rejuvenation. The authors’ clinical experience with a specific yellow light-emitting diode device was mixed, depending on the condition being treated, and was likely influenced by the device parameters. PMID:26155326

  13. Lighting for Schools.

    ERIC Educational Resources Information Center

    Benya, James R.

    This publication highlights some of the benefits of proper daylighting design in educational facilities, discusses energy efficient electric lighting choices schools can make that are long lasting and require little maintenance, and offers six steps for designing lighting systems that use half the energy of earlier conventional designs. Several…

  14. Incoherent Light Sources

    NASA Astrophysics Data System (ADS)

    Bertram, Dietrich; Born, Matthias; Jüstel, Thomas

    Since the invention and industrialization of incandescent lamps at the end radiation of the 19th century electrical lighting has become a commodity in our daily life. Today, incoherent light sources are used for numerous application areas. Major improvements have been achieved over the past decades with respect to lamp efficiency (Fig. 10.1), lifetime and color properties.

  15. Incoherent Light Sources

    NASA Astrophysics Data System (ADS)

    Bertram, Dietrich; Born, Matthias; Jüstel, Thomas

    Since the invention and industrialization of incandescent lamps at the end of the 19th century electrical lighting has become a commodity in our daily life. Today, incoherent light sources are used for numerous application areas. Major improvements have been achieved over the past decades with respect to lamp efficiency Fig. 10.1, lifetime and color properties.

  16. Demand-controlled lighting

    NASA Technical Reports Server (NTRS)

    Owens, L. J.

    1977-01-01

    Automatic lighting is controlled by photocell that measures intensity of available light. Photocell drives motor which operates mercury switches controlling indoor illumination sources. Device effects increase in indoor illumination intensity when illumination input to cell is insufficient. Reverse is true if input is too great.

  17. Lighting at computer workstations.

    PubMed

    Osterhaus, Werner; Hemphälä, Hillevi; Nylén, Per

    2015-01-01

    The visual conditions for computer work are complex and include several factors that need to be well controlled. These factors include the lighting system, the design of the computer and screen itself, the screens position and orientation within the room, the surface reflectances and colours of the room, and the visualability of the worker. The objective was to review the literature (including standards) on lighting for computer work in an accessible summary. This contribution focuses on lighting for computer work, but the reader is reminded of the fact that lighting continuously interacts with the other factors mentioned above. The combined visual conditions shall enable the worker to see and perform the work task without causing unnecessary strain for the eyes or the other parts of the body. The main lighting-related factors in the visual environment to evaluate are: illuminance, luminance, direction of light, glare, correlated colour temperature of the light source (CCT), colour rendering of the light source, and the non-visual effects (such as non-visual flicker). A visual ergonomics checklist is presented as a guide to analyse the visual environment.

  18. Lighting in Architectural Design.

    ERIC Educational Resources Information Center

    Phillips, Derek

    The primary function of this book is to treat the topic of lighting design in such a manner as to bridge the gap between architects and illuminating engineers. The work is divided into three parts: Part I, Principles of Design, offers information and analysis of how natural and artificial lighting affects building design, how illumination levels…

  19. Handrail Lighting Module

    NASA Technical Reports Server (NTRS)

    Mattei, John P.

    1988-01-01

    Lightweight, space-saving combined handrail-and-flourescent-light unit serves decorative or safety functions. Fluorescent lamp mounted inside clear tubular plastic housing shaped to form handrail. Designed for either temporary or permanent installation or part of emergency lighting system.

  20. Handrail Lighting Module

    NASA Technical Reports Server (NTRS)

    Mattei, John P.

    1988-01-01

    Lightweight, space-saving combined handrail-and-flourescent-light unit serves decorative or safety functions. Fluorescent lamp mounted inside clear tubular plastic housing shaped to form handrail. Designed for either temporary or permanent installation or part of emergency lighting system.

  1. Shedding Some Light.

    ERIC Educational Resources Information Center

    Whitney, Tim

    1998-01-01

    Discusses the basics of designing natural and artificial light in an indoor athletic facility. Also examines individual lighting requirements of typical rooms such as weight and fitness rooms, aerobics and multipurpose rooms, gymnasiums, field houses, pools, and racquetball and squash courts. (GR)

  2. OBSTRUCTION LIGHT SYSTEM.

    DTIC Science & Technology

    The report describes the design, development and fabrication of a prototype high intensity obstruction lighting system. A detailed light source ... study was made which indicated a newly developed lamp consisting of a quartz-iodide lamp sealed in a parabolic envelope, was the most advantageous type

  3. Shedding Some Light.

    ERIC Educational Resources Information Center

    Whitney, Tim

    1998-01-01

    Discusses the basics of designing natural and artificial light in an indoor athletic facility. Also examines individual lighting requirements of typical rooms such as weight and fitness rooms, aerobics and multipurpose rooms, gymnasiums, field houses, pools, and racquetball and squash courts. (GR)

  4. Enriching lighting design.

    PubMed

    Brawley, Elizabeth C

    2009-01-01

    Good lighting is perhaps the most important and least understood element in designing healthcare environments. Both physically and mentally challenged individuals become more vulnerable and dependent on their environment to compensate for sensory impairments, including dimming eyesight, which interferes to some degree with daily activities as well as social and leisure activities - the things that provide emotional and social well-being. Too few building designs today result in lighting that meets the needs of these individuals, regardless of age. Typical lighting in most care environments is inadequate to meet lighting needs affecting both vision and the photobiological (non-visual) needs of synchronization of circadian rhythm, which impacts sleep and depression. Well-designed lighting is one of the most important design elements that will support an individual's ability to perform normal daily activities and decrease the level of disability associated with these impairments. Daylight contains the spectrum to which the circadian clock is most sensitive and provides higher light levels during the day. Easily accessible outdoor gardens encourage individuals outside, providing the necessary regular exposure to direct bright light that sunlight provides. The combination good interior lighting and regular daylight exposure contributes to regaining and maintaining an active and fulfilling lifestyle - greatly improving quality of life.

  5. Splayed mirror light pipes

    SciTech Connect

    Swift, P.D.

    2010-02-15

    An expression is given for the transmission of the rectangular-section mirror light pipe. The expression is used to model throughputs for simulated solar conditions over a calender year. It is found that the splaying of a mirror light pipe results in a significant increase in throughputs particularly in winter months. (author)

  6. Explosively pumped laser light

    DOEpatents

    Piltch, Martin S.; Michelotti, Roy A.

    1991-01-01

    A single shot laser pumped by detonation of an explosive in a shell casing. The shock wave from detonation of the explosive causes a rare gas to luminesce. The high intensity light from the gas enters a lasing medium, which thereafter outputs a pulse of laser light to disable optical sensors and personnel.

  7. Light Verbs and Polysemy.

    ERIC Educational Resources Information Center

    Brugman, Claudia

    2001-01-01

    Examines the relationship between the polysemic structure of main verbs and their light counterparts. Suggests that light verbs are systematically related to their heavy counterparts in retaining the force-dynamic properties of the heavy sense, but that the conceptual domain in which that force-dynamic structure applies shifts from the physical to…

  8. Physiological Characteristics and Production of Folic Acid of Lactobacillus plantarum JA71 Isolated from Jeotgal, a Traditional Korean Fermented Seafood

    PubMed Central

    Lim, Sang-Dong

    2014-01-01

    Folic acid, one of the B group of vitamins, is an essential substance for maintaining the functions of the nervous system, and is also known to decrease the level of homocysteine in plasma. Homocysteine influences the lowering of the cognitive function in humans, and especially in elderly people. In order to determine the strains with a strong capacity to produce folic acid, 190 bacteria were isolated from various kinds of jeotgal and chungkuk-jang. In our test experiment, JA71 was found to contain 9.03μg/mL of folic acid after 24 h of incubation in an MRS broth. This showed that JA71 has the highest folic acid production ability compared to the other lactic acid bacteria that were isolated. JA71 was identified as Lactobacillus plantarum by the result of API carbohydrate fermentation pattern and 16s rDNA sequence. JA71 was investigated for its physiological characteristics. The optimum growth temperature of JA71 was 37℃, and the cultures took 12 h to reach pH 4.4. JA71 proved more sensitive to bacitracin when compared with fifteen different antibiotics, and showed most resistance to neomycin and vancomycin. Moreover, it was comparatively tolerant of bile juice and acid, and displayed resistance to Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus with restraint rates of 60.4%, 96.7%, and 76.2%, respectively. These results demonstrate that JA71 could be an excellent strain for application to functional products. PMID:26760752

  9. The light ion trough.

    NASA Technical Reports Server (NTRS)

    Taylor, H. A., Jr.

    1972-01-01

    A distinct feature of the ion composition results from the OGO-2, 4 and 6 satellites is the light ion trough, wherein the mid-latitude concentrations of H+ and He+ decrease sharply with latitude. In contrast to the 'main trough' in electron density observed primarily as a nightside phenomenon, the light ion trough persists during both day and night. For daytime winter hemisphere conditions and for all seasons during night, the mid-latitude light ion concentration decrease is a pronounced feature. In the dayside summer and equinox hemispheres, the rate of light ion decrease with latitude is comparatively gradual, and the trough boundary is less well defined, particularly for quiet magnetic conditions. In response to magnetic storms, the light ion trough minimum moves equatorward, and deepens, consistent with earlier evidence of the contraction of the plasmasphere in response to storm time enhancements in magnetospheric plasma convection.

  10. Superbunching pseudothermal light

    NASA Astrophysics Data System (ADS)

    Zhou, Yu; Li, Fu-li; Bai, Bin; Chen, Hui; Liu, Jianbin; Xu, Zhuo; Zheng, Huaibin

    2017-05-01

    A simple superbunching pseudothermal light source is introduced based on common instruments such as laser, lenses, pinholes, and ground glasses. g(2 )(0 ) =3.66 ±0.02 is observed in the suggested scheme by employing two rotating ground glasses. Quantum and classical theories are employed to interpret the observed superbunching effect. It is predicted that g(2 )(0 ) can reach 2N if N rotating ground glasses were employed. These results are helpful to understand the physics of superbunching. The proposed superbunching pseudothermal light may serve as a type of light to study the second- and higher-order coherence of light and have potential application in improving the visibility of thermal light ghost imaging.

  11. Stray Light Analysis

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Based on a Small Business Innovation Research contract from the Jet Propulsion Laboratory, TracePro is state-of-the-art interactive software created by Lambda Research Corporation to detect stray light in optical systems. An image can be ruined by incidental light in an optical system. To maintain image excellence from an optical system, stray light must be detected and eliminated. TracePro accounts for absorption, specular reflection and refraction, scattering and aperture diffraction of light. Output from the software consists of spatial irradiance plots and angular radiance plots. Results can be viewed as contour maps or as ray histories in tabular form. TracePro is adept at modeling solids such as lenses, baffles, light pipes, integrating spheres, non-imaging concentrators, and complete illumination systems. The firm's customer base includes Lockheed Martin, Samsung Electronics and other manufacturing, optical, aerospace, and educational companies worldwide.

  12. Lightness, illumination, and gradients.

    PubMed

    Todorović, Dejan

    2006-01-01

    The illumination interpretation approach claims that lightness illusions can be explained as misapplications of lightness constancy mechanisms, processes which usually enable veridical extraction of surface reflectance from luminance distributions by discounting illumination. In particular, luminance gradients are thought to provide cues about the interactions of light and surfaces. Several examples of strong lightness illusions are discussed for which explanations based on illumination interpretation can be proposed. In criticisms of this approach, a variety of demonstrations of similarly structured control displays are presented, which involve equivalent lightness effects that cannot readily be accounted for by illumination interpretation mechanisms. Furthermore, a number of known and novel displays are presented that demonstrate effects of gradients on the qualitative appearance of uniform regions. Finally, some simple simulations of neural effects of luminance distributions are discussed.

  13. Light dispersion in space

    NASA Astrophysics Data System (ADS)

    Barbosa, L. C.

    2015-09-01

    Considering an idea of F. Arago in 1853 regarding light dispersion through the light ether in the interstellar space, this paper presents a new idea on an alternative interpretation of the cosmological red shift of the galaxies in the universe. The model is based on an analogy with the temporal material dispersion that occurs with light in the optical fiber core. Since intergalactic space is transparent, according to the model, this phenomenon is related to the gravitational potential existing in the whole space. Thus, it is possible to find a new interpretation to Hubble's constant. In space, light undergoes a dispersion process in its path, which is interpreted by a red shift equation of the type Δz = HL, since H = (d2n/dλ2 Δv Δλ), where H means the Hubble constant, n is the refractive index of the intergalactic space, Δλ is the spectral width of the extragalactic source, and Δv is the variation of the speed of light caused by the gravitational potential. We observe that this "constant" is governed by three new parameters. Light traveling the intergalactic space undergoes red shift due to this mechanism, while light amplitude decreases with time, and the wavelength always increases, thus producing the same type of behavior given by Hubble's Law. It can be demonstrated that the dark matter phenomenon is produced by the apparent speed of light of the stars on the periphery of the galaxies, without the existence of dark energy. Based on this new idea, the model of the universe is static, lacking expansion. Other phenomena may be interpreted based on this new model of the universe. We have what we call temporal gravitational dispersion of light in space produced by the variations of the speed of light, due to the presence of the gravitational potential in the whole space.

  14. Lighting Techniques for the ETV Studio.

    ERIC Educational Resources Information Center

    American School and University, 1966

    1966-01-01

    Various lighting techniques for educational television production are discussed. Television lighting calls for many angles, quantities, and distributions of light which fall into the following categories--(1) high key light, (2) low key light, (3) key light, (4) base light, (5) fill light, (6) cross light, (7) back light, (8) side back light, (9)…

  15. Light mesons on the light front

    SciTech Connect

    Naito, K.; Maedan, S.; Itakura, K.

    2004-11-01

    We study the properties of light mesons in the scalar, pseudoscalar, and vector channels within the light-front quantization, by using the (one flavor) Nambu-Jona-Lasinio model with vector interaction. After taking into account the effects of chiral symmetry breaking, we derive the bound-state equation in each channel in the large N limit (N is the number of colors), which means that we consider the lowest qq Fock state with the constituent quark and antiquark. By solving the bound-state equation, we simultaneously obtain a mass and a light cone (LC) wave function of the meson. While we reproduce the previous results for the scalar and pseudoscalar mesons, we find that, for a vector meson, the bound-state equations for the transverse and longitudinal polarizations look different from each other. However, eventually after imposing a cutoff which is invariant under the parity and boost transformations, one finds these two are identical, giving the same mass and the same (spin-independent) LC wave function. When the vector interaction becomes larger than a critical value, the vector state forms a bound state, whose mass decreases as the interaction becomes stronger. While the LC wave function of the pseudoscalar meson is broadly distributed in longitudinal momentum (x) space, that of the vector meson is squeezed around x=1/2.

  16. 3. View from former light tower to Cape Elizabeth Light ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. View from former light tower to Cape Elizabeth Light Tower, view northeast, southwest side of Cape Elizabeth Tower - Cape Elizabeth Light Station, Near Two Lights State Park at end of Two Lights Road, off State Highway 77, Cape Elizabeth, Cumberland County, ME

  17. [Xenon light therapy].

    PubMed

    Kanai, Akifumi

    2012-07-01

    The xenon light, generated by high-intensity electrical stimulation of xenon gas, is used to sterilize wounds, aid tissue repair, and relieve pain as a low-level light therapy. The light produced consists of non-coherent beams of multiple wavelengths in the ultraviolet to infrared spectrum. This broad-band light can be emitted in a continuous wave or pulsed mode, with the wave band chosen and the energy distribution controlled for the purpose. Specifically, wavelengths in the 500-700 nm range are suitable for treating superficial tissue, and wavelengths between 800 and 1,000 nm are suitable for deeper-seated tissues, due to longer optical penetration distances through tissue. One of the most common benefits in the xenon light therapy is considered to be the wide and deep irradiation of optimal rays to living tissue. Research into the use of xenon light for tissue repair and pain reduction is restricted within open-label studies and case reports. The present review expounded the effects of xenon light therapy on the basis of the available evidence in vitro and in vivo studies using a laser beam of single wavelength.

  18. New Enhanced Artificial Bee Colony (JA-ABC5) Algorithm with Application for Reactive Power Optimization

    PubMed Central

    2015-01-01

    The standard artificial bee colony (ABC) algorithm involves exploration and exploitation processes which need to be balanced for enhanced performance. This paper proposes a new modified ABC algorithm named JA-ABC5 to enhance convergence speed and improve the ability to reach the global optimum by balancing exploration and exploitation processes. New stages have been proposed at the earlier stages of the algorithm to increase the exploitation process. Besides that, modified mutation equations have also been introduced in the employed and onlooker-bees phases to balance the two processes. The performance of JA-ABC5 has been analyzed on 27 commonly used benchmark functions and tested to optimize the reactive power optimization problem. The performance results have clearly shown that the newly proposed algorithm has outperformed other compared algorithms in terms of convergence speed and global optimum achievement. PMID:25879054

  19. AUTOMATIC LIGHT CONTROL

    DOEpatents

    Artzt, M.

    1957-08-27

    A control system for a projection kinescope used in a facsimile scanning system and, in particular, meams for maintaining substantially constant the light emanating from the flying spot on the face of the kinescope are described. In general, the invention provides a feeler member disposed in such a position with respect to a projecting lens as to intercept a portion of the light striking the lens. Suitable circuitry in conjunction with a photomultiplier tube provides a signal proportional to the light intensity of the flying spot. The grid bias on the kinescope is controlled by this signal to maintain the intensity of the spot substantially constant.

  20. Retinal light toxicity

    PubMed Central

    Youssef, P N; Sheibani, N; Albert, D M

    2011-01-01

    The ability of light to enact damage on the neurosensory retina and underlying structures has been well understood for hundreds of years. While the eye has adapted several mechanisms to protect itself from such damage, certain exposures to light can still result in temporal or permanent damage. Both clinical observations and laboratory studies have enabled us to understand the various ways by which the eye can protect itself from such damage. Light or electromagnetic radiation can result in damage through photothermal, photomechanical, and photochemical mechanisms. The following review seeks to describe these various processes of injury and many of the variables, which can mitigate these modes of injury. PMID:21178995

  1. Light harvesting dendrimers.

    PubMed

    Nantalaksakul, Arpornrat; Reddy, D Raghunath; Bardeen, Christopher J; Thayumanavan, S

    2006-01-01

    Tree-like dendrimers with decreasing number of chromophores from periphery to core is an attractive candidate for light-harvesting applications. Numerous dendritic designs with different kinds of light-collecting chromophores at periphery and an energy-sink at the core have been demonstrated with high energy transfer efficiency. These building blocks are now being developed for several applications such as light-emitting diodes, frequency converters and other photonic devices. This review outlines the efforts that are based on both conjugated and non-conjugated dendrimers.

  2. Light-weight plastination.

    PubMed

    Steinke, Hanno; Rabi, Suganthy; Saito, Toshiyuki; Sawutti, Alimjan; Miyaki, Takayoshi; Itoh, Masahiro; Spanel-Borowski, Katharina

    2008-11-20

    Plastination is an excellent technique which helps to keep the anatomical specimens in a dry, odourless state. Since the invention of plastination technique by von Hagens, research has been done to improve the quality of plastinated specimens. In this paper, we have described a method of producing light-weight plastinated specimens using xylene along with silicone and in the final step, substitute xylene with air. The finished plastinated specimens were light-weight, dry, odourless and robust. This method requires less use of resin thus making the plastination technique more cost-effective. The light-weight specimens are easy to carry and can easily be used for teaching.

  3. Differentiating spatial light modulator

    NASA Astrophysics Data System (ADS)

    Armitage, D.

    1985-04-01

    A differentiating spatial light modulator device in which a photoreceptor and an electro-optic crystal are isolated by a dielectric mirror is discussed. The electro-optic crystal is configured to have low or zero longitudinal response, yet is sensitive to transverse electric fields. The fringe field generated by the photoreceptor (photodiode) modulates the crystal birefringence. Readout via a polarizing beamsplitter gives an output light related to the spatial gradient of the input light. In a liquid crystal embodiment of the invention, reversal of the applied voltage gives a driven off state which speeds the erasure. Storage is possible in the smectic liquid crystal phase.

  4. Light multinary computing

    NASA Astrophysics Data System (ADS)

    Arago, Jaime

    2012-11-01

    Next-generation optical communication and optical computing imply an evolution from binary to multinary computing. Light multinary computing encodes data using pulses of light components in higher orders than binary and processes it using truth tables larger than Boolean ones. This results in lesser encoded data that can be processed at faster speeds. We use a general-purpose optical transistor as the building block to develop the main computing units for counting, distributing, storing, and logically operating the arithmetic addition of two bytes of base-10 data. Currently available optical switching technologies can be used to physically implement light multinary computing to achieve ultra-high speed communication and computing.

  5. White light velocity interferometer

    DOEpatents

    Erskine, D.J.

    1999-06-08

    The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s. 41 figs.

  6. White light velocity interferometer

    DOEpatents

    Erskine, D.J.

    1997-06-24

    The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s. 41 figs.

  7. White light velocity interferometer

    DOEpatents

    Erskine, David J.

    1999-01-01

    The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s.

  8. White light velocity interferometer

    DOEpatents

    Erskine, David J.

    1997-01-01

    The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s.

  9. City Lights of Europe

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Growth in 'mega-cities' is altering the landscape and the atmosphere in such a way as to curtail normal photosynthesis. By using data from The Defense Meteorological Satellite Program's Operational Linescan System, researchers have been able to look at urban sprawl by monitoring the emission of light from cities at night. By overlaying these 'light maps' onto other data such as soil and vegetation maps, the research shows that urbanization can have a variable but measurable impact on photosynthetic productivity. For more information, read Bright Lights, Big City Image by the NASA GSFC Scientific Visualization Studio

  10. Green Light Pulse Oximeter

    DOEpatents

    Scharf, John Edward

    1998-11-03

    A reflectance pulse oximeter that determines oxygen saturation of hemoglobin using two sources of electromagnetic radiation in the green optical region, which provides the maximum reflectance pulsation spectrum. The use of green light allows placement of an oximetry probe at central body sites (e.g., wrist, thigh, abdomen, forehead, scalp, and back). Preferably, the two green light sources alternately emit light at 560 nm and 577 nm, respectively, which gives the biggest difference in hemoglobin extinction coefficients between deoxyhemoglobin, RHb, and oxyhemoglobin, HbO.sub.2.

  11. Aniline is an inducer, and not a precursor, for indole derivatives in Rubrivivax benzoatilyticus JA2.

    PubMed

    Mujahid, Mohammed; Sasikala, Ch; Ramana, Ch V

    2014-01-01

    Rubrivivax benzoatilyticus JA2 and other anoxygenic photosynthetic bacteria produce indole derivatives when exposed to aniline, a xenobiotic compound. Though this phenomenon has been reported previously, the role of aniline in the production of indoles is still a biochemical riddle. The present study aims at understanding the specific role of aniline (as precursor or stimulator) in the production of indoles and elucidating the biochemical pathway of indoles in aniline-exposed cells by using stable isotope approaches. Metabolic profiling revealed tryptophan accumulation only in aniline exposed cells along with indole 3-acetic acid (IAA) and indole 3-aldehyde (IAld), the two major catabolites of tryptophan. Deuterium labelled aniline feeding studies revealed that aniline is not a precursor of indoles in strain JA2. Further, production of indoles only in aniline-exposed cells suggests that aniline is an indoles stimulator. In addition, production of indoles depended on the presence of a carbon source, and production enhanced when carbon sources were added to the culture. Isotope labelled fumarate feeding identified, fumarate as the precursor of indole, indicating de novo synthesis of indoles. Glyphosate (shikimate pathway inhibitor) inhibited the indoles production, accumulation of tryptophan, IAA and IAld indicating that indoles synthesis in strain JA2 occurs via the de novo shikimate pathway. The up-regulation of anthranilate synthase gene and induction of anthranilate synthase activity correlated well with tryptophan production in strain JA2. Induction of tryptophan aminotransferase and tryptophan 2-monooxygenase activities corroborated well with IAA levels, suggesting that tryptophan catabolism occurs simultaneously in aniline exposed cells. Our study demonstrates that aniline (stress) stimulates tryptophan/indoles synthesis via the shikimate pathway by possibly modulating the metabolic pathway.

  12. Aniline Is an Inducer, and Not a Precursor, for Indole Derivatives in Rubrivivax benzoatilyticus JA2

    PubMed Central

    Mohammed, Mujahid; Ch, Sasikala; Ch, Ramana V.

    2014-01-01

    Rubrivivax benzoatilyticus JA2 and other anoxygenic photosynthetic bacteria produce indole derivatives when exposed to aniline, a xenobiotic compound. Though this phenomenon has been reported previously, the role of aniline in the production of indoles is still a biochemical riddle. The present study aims at understanding the specific role of aniline (as precursor or stimulator) in the production of indoles and elucidating the biochemical pathway of indoles in aniline-exposed cells by using stable isotope approaches. Metabolic profiling revealed tryptophan accumulation only in aniline exposed cells along with indole 3-acetic acid (IAA) and indole 3-aldehyde (IAld), the two major catabolites of tryptophan. Deuterium labelled aniline feeding studies revealed that aniline is not a precursor of indoles in strain JA2. Further, production of indoles only in aniline-exposed cells suggests that aniline is an indoles stimulator. In addition, production of indoles depended on the presence of a carbon source, and production enhanced when carbon sources were added to the culture. Isotope labelled fumarate feeding identified, fumarate as the precursor of indole, indicating de novo synthesis of indoles. Glyphosate (shikimate pathway inhibitor) inhibited the indoles production, accumulation of tryptophan, IAA and IAld indicating that indoles synthesis in strain JA2 occurs via the de novo shikimate pathway. The up-regulation of anthranilate synthase gene and induction of anthranilate synthase activity correlated well with tryptophan production in strain JA2. Induction of tryptophan aminotransferase and tryptophan 2-monooxygenase activities corroborated well with IAA levels, suggesting that tryptophan catabolism occurs simultaneously in aniline exposed cells. Our study demonstrates that aniline (stress) stimulates tryptophan/indoles synthesis via the shikimate pathway by possibly modulating the metabolic pathway. PMID:24533057

  13. Resistance of Fusarium poae in Arabidopsis leaves requires mainly functional JA and ET signaling pathways.

    PubMed

    Dinolfo, María Inés; Castañares, Eliana; Stenglein, Sebastián A

    2017-10-01

    Fusarium poae has been considered as a minor species among those that cause the FHB disease but in recent years several researchers have documented a high frequency of occurrence in several crops. We evaluated the ability of F. poae to produce symptoms in A. thaliana leaves. Moreover, we analyzed the defense of A. thaliana against F. poae using SA, JA, and ET mutants and we monitored the expression level of genes involved in the main signaling pathways related to plant defense. Symptoms were observed in the inoculated leaves demonstrating the ability of F. poae to infect A. thaliana leaves. Moreover, the npr1-1 mutants presented low symptoms compared to Col-0, etr2-1, and coi1-1 and that the coi1-1 mutant was the most susceptible genotypes followed by etr2-1 genotypes. The RT-PCR revealed that PDF1.2, CHI/PR3, and ERF1, three important JA-ET responsive genes and NPR1 and PR1, which are regulated by SA signaling, were expressed upon F. poae inoculation. Our results suggest that JA and ET could play a key role in Arabidopsis leaves defense against F. poae representing the first evaluation of the response of the main A. thaliana phytohormones involved in plant defense in the presence of F. poae. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  14. Biosynthesis of silver and zinc oxide nanoparticles using Pichia fermentans JA2 and their antimicrobial property

    NASA Astrophysics Data System (ADS)

    Chauhan, Ritika; Reddy, Arpita; Abraham, Jayanthi

    2015-01-01

    The development of eco-friendly alternative to chemical synthesis of metal nanoparticles is of great challenge among researchers. The present study aimed to investigate the biological synthesis, characterization, antimicrobial study and synergistic effect of silver and zinc oxide nanoparticles against clinical pathogens using Pichia fermentans JA2. The extracellular biosynthesis of silver and zinc oxide nanoparticles was investigated using Pichia fermentans JA2 isolated from spoiled fruit pulp bought in Vellore local market. The crystalline and stable metallic nanoparticles were characterized evolving several analytical techniques including UV-visible spectrophotometer, X-ray diffraction pattern analysis and FE-scanning electron microscope with EDX-analysis. The biosynthesized metallic nanoparticles were tested for their antimicrobial property against medically important Gram positive, Gram negative and fungal pathogenic microorganisms. Furthermore, the biosynthesized nanoparticles were also evaluated for their increased antimicrobial activities with various commercially available antibiotics against clinical pathogens. The biosynthesized silver nanoparticles inhibited most of the Gram negative clinical pathogens, whereas zinc oxide nanoparticles were able to inhibit only Pseudomonas aeruginosa. The combined effect of standard antibiotic disc and biosynthesized metallic nanoparticles enhanced the inhibitory effect against clinical pathogens. The biological synthesis of silver and zinc oxide nanoparticles is a novel and cost-effective approach over harmful chemical synthesis techniques. The metallic nanoparticles synthesized using Pichia fermentans JA2 possess potent inhibitory effect that offers valuable contribution to pharmaceutical associations.

  15. Shining a Light on Electronics

    ERIC Educational Resources Information Center

    Statler, James D.

    2009-01-01

    While they produced a limited amount of light when first introduced, light-emitting diode (LED) lights offered the benefit of rarely burning out. As a result, they were initially used primarily as indicator lights. Advances in the technology have made available LEDs that produce far brighter light, and one application that has come to market is…

  16. Shining a Light on Electronics

    ERIC Educational Resources Information Center

    Statler, James D.

    2009-01-01

    While they produced a limited amount of light when first introduced, light-emitting diode (LED) lights offered the benefit of rarely burning out. As a result, they were initially used primarily as indicator lights. Advances in the technology have made available LEDs that produce far brighter light, and one application that has come to market is…

  17. 10. LIGHT TOWER, VIEW NORTHEAST FROM LIGHT PLATFORM, SOUTHWEST SIDE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. LIGHT TOWER, VIEW NORTHEAST FROM LIGHT PLATFORM, SOUTHWEST SIDE OF BOAT HOUSE AND KEEPER'S HOUSE, WITH DETAIL OF RAILING IN FOREGROUND - Grindle Point Light Station, Western end of Ferry Road on Grindle Point, Islesboro, Waldo County, ME

  18. Polarized Light Corridor Demonstrations.

    ERIC Educational Resources Information Center

    Davies, G. R.

    1990-01-01

    Eleven demonstrations of light polarization are presented. Each includes a brief description of the apparatus and the effect demonstrated. Illustrated are strain patterns, reflection, scattering, the Faraday Effect, interference, double refraction, the polarizing microscope, and optical activity. (CW)

  19. Light Seconds from Dione

    NASA Image and Video Library

    2006-01-05

    After journeying a bit more than an hour across the Solar System, bright sunlight reflects off the gleaming icy cliffs in the wispy terrain of Dione and is captured by NASA Cassini spacecraft cameras several light seconds later

  20. Light and Dark Tricks

    NASA Image and Video Library

    2010-10-04

    Capturing the interplay between light and shadow, NASA Cassini spacecraft looks toward the night side of Saturn where sunlight reflected off the rings has dimly illuminated what would otherwise be the dark side of the planet.

  1. Into the Light

    NASA Image and Video Library

    2006-10-27

    As ring particles emerge from the darkness of Saturn shadow, they pass through a region of twilight. The Sun light, refracted by the planet atmosphere, peeks around the limb, followed shortly by the Sun itself

  2. Light-toned Terraces

    NASA Image and Video Library

    2006-05-29

    This MOC image shows light-toned, layered, sedimentary rock outcrops in northwest Schiaparelli Basin. The layers are all of about the same thickness a few meters or less and appear to have similar properties

  3. Global City Lights

    NASA Image and Video Library

    2000-11-09

    The Eastern U.S., Europe, and Japan are brightly lit by their cities, while interiors of Africa, Asia, Australia, and South America are dark and lightly populated in this image created in 2000 by NASA Goddard Space Flight Center.

  4. Light Duty Vehicle Program

    EPA Pesticide Factsheets

    View a fact sheet on how the Final Endangerment Finding will allow EPA to finalize the first greenhouse gas standards for new light-duty vehicles as part of the joint rulemaking with the Department of Transportation.

  5. Shedding Light on Nanomedicine

    PubMed Central

    Tong, Rong

    2012-01-01

    Light is electromagnetic radiation that can convert its energy into different forms (e.g., heat, chemical energy, and acoustic waves). This property has been exploited in phototherapy (e.g., photothermal therapy and photodynamic therapy) and optical imaging (e.g., fluorescence imaging) for therapeutic and diagnostic purposes. Light-controlled therapies can provide minimally or non-invasive spatiotemporal control as well as deep tissue penetration. Nanotechnology provides a numerous advantages, including selective targeting of tissues, prolongation of therapeutic effect, protection of active payloads, and improved therapeutic indices. This review explores the advances that nanotechnology can bring to light-based therapies and diagnostics, and vice versa, including photo-triggered systems, nanoparticles containing photoactive molecules, and nanoparticles that are themselves photoactive. Limitations of light-based therapies such as photic injury and phototoxicity will be discussed. PMID:22887840

  6. Cauldron of Light

    NASA Image and Video Library

    In this animation, a seething cauldron of light appears to bubble and ooze around the remains of a giant star that astronomers have been watching tear itself apart for the last 300 years. This movi...

  7. National Synchrotron Light Source

    ScienceCinema

    None

    2016-07-12

    A tour of Brookhaven's National Synchrotron Light Source (NSLS). The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviole

  8. Dark light Higgs bosons.

    SciTech Connect

    Draper, P.; Liu, T.; Wagner, C. E. M.; Wang, L.-T.; Zhang, H.

    2011-03-24

    We study a limit of the nearly Peccei-Quinn-symmetric next-to-minimal supersymmetric standard model possessing novel Higgs and dark matter (DM) properties. In this scenario, there naturally coexist three light singletlike particles: a scalar, a pseudoscalar, and a singlinolike DM candidate, all with masses of order 0.1-10 GeV. The decay of a standard model-like Higgs boson to pairs of the light scalars or pseudoscalars is generically suppressed, avoiding constraints from collider searches for these channels. For a certain parameter window annihilation into the light pseudoscalar and exchange of the light scalar with nucleons allow the singlino to achieve the correct relic density and a large direct-detection cross section consistent with the DM direct-detection experiments, CoGeNT and DAMA/LIBRA, preferred region simultaneously. This parameter space is consistent with experimental constraints from LEP, the Tevatron, ?, and flavor physics.

  9. Exotic Light Nuclei

    ERIC Educational Resources Information Center

    Cerny, Joseph; Poskanzer, Arthur M.

    1978-01-01

    Among the light elements, nuclei with unequal numbers of protons and neutrons are highly unstable. Some survive just long enough to be detected and exhibit unusual regimes of radioactive decay. ( Autor/MA)

  10. Exotic Light Nuclei

    ERIC Educational Resources Information Center

    Cerny, Joseph; Poskanzer, Arthur M.

    1978-01-01

    Among the light elements, nuclei with unequal numbers of protons and neutrons are highly unstable. Some survive just long enough to be detected and exhibit unusual regimes of radioactive decay. ( Autor/MA)

  11. Ferroelectric Light Control Device

    NASA Technical Reports Server (NTRS)

    Park, Yeonjoon (Inventor); Choi, Sang H. (Inventor); King, Glen C. (Inventor); Kim, Jae-Woo (Inventor); Elliott, Jr., James R. (Inventor)

    2008-01-01

    A light control device is formed by ferroelectric material and N electrodes positioned adjacent thereto to define an N-sided regular polygonal region or circular region there between where N is a multiple of four.

  12. Polarized Light Corridor Demonstrations.

    ERIC Educational Resources Information Center

    Davies, G. R.

    1990-01-01

    Eleven demonstrations of light polarization are presented. Each includes a brief description of the apparatus and the effect demonstrated. Illustrated are strain patterns, reflection, scattering, the Faraday Effect, interference, double refraction, the polarizing microscope, and optical activity. (CW)

  13. National Synchrotron Light Source

    SciTech Connect

    2009-03-10

    A tour of Brookhaven's National Synchrotron Light Source (NSLS). The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviole

  14. Light on curved backgrounds

    NASA Astrophysics Data System (ADS)

    Batic, D.; Nelson, S.; Nowakowski, M.

    2015-05-01

    We consider the motion of light on different spacetime manifolds by calculating the deflection angle, lensing properties and by probing into the possibility of bound states. The metrics in which we examine the light motion include, among other items, a general relativistic dark matter metric, a dirty black hole, and a worm hole metric, the last two inspired by noncommutative geometry. The lensing in a holographic screen metric is discussed in detail. We study also the bending of light around naked singularities like, e.g., the Janis-Newman-Winicour metric and include other cases. A generic property of light behavior in these exotic metrics is pointed out. For the standard metric like the Schwarzschild and Schwarzschild-de Sitter cases, we improve the accuracy of the lensing results for the weak and strong regimes.

  15. Magic of Light

    NASA Astrophysics Data System (ADS)

    Curticapean, Dan

    2010-08-01

    This paper focuses on the concept of the website "Magic of Light", an internet platform that offers podcasts, slides, pictures, Flash animations and educational materials to allow a better understanding in optics and photonics.

  16. Light, Color, and Mirrors.

    ERIC Educational Resources Information Center

    Tiburzi, Brian; Tamborino, Laurie; Parker, Gordon A.

    2000-01-01

    Describes an exercise in which students can use flashlights, mirrors, and colored paper to discover scientific principles regarding optics. Addresses the concepts of angles of incidence and reflection, colored vs. white light, and mirror images. (WRM)

  17. Indoor Lighting Facilities

    NASA Astrophysics Data System (ADS)

    Matsushima, Koji; Saito, Yoshinori; Ichikawa, Shigenori; Kawauchi, Takao; Tanaka, Tsuneo; Hirano, Rika; Tazuke, Fuyuki

    According to the statistics by the Ministry of Land, Infrastructure and Transport, the total floor space of all building construction started was 188.87 million m2 (1.5% increase y/y), marking the fourth straight year of increase. Many large-scale buildings under construction in central Tokyo become fully occupied by tenants before completion. As for office buildings, it is required to develop comfortable and functional office spaces as working styles are becoming more and more diversified, and lighting is also an element of such functionalities. The total floor space of construction started for exhibition pavilions, multipurpose halls, conference halls and religious architectures decreased 11.1% against the previous year. This marked a decline for 10 consecutive years and the downward trend continues. In exhibition pavilions, the light radiation is measured and adjusted throughout the year so as not to damage the artworks by lighting. Hospitals, while providing higher quality medical services and enhancing the dwelling environment of patients, are expected to meet various restrictions and requirements, including the respect for privacy. Meanwhile, lighting designs for school classrooms tend to be homogeneous, yet new ideas are being promoted to strike a balance between the economical and functional aspects. The severe economic environment continues to be hampering the growth of theaters and halls in both the private and public sectors. Contrary to the downsizing trend of such facilities, additional installations of lighting equipment were conspicuous, and the adoption of high efficacy lighting appliances and intelligent function control circuits are becoming popular. In the category of stores/commercial facilities, the construction of complex facilities is a continuing trend. Indirect lighting, high luminance discharge lamps with excellent color rendition and LEDs are being effectively used in these facilities, together with the introduction of lighting designs

  18. Ocular hazards of light

    NASA Technical Reports Server (NTRS)

    Sliney, David H.

    1994-01-01

    The eye is protected against bright light by the natural aversion response to viewing bright light sources. The aversion response normally protects the eye against injury from viewing bright light sources such as the sun, arc lamps and welding arcs, since this aversion limits the duration of exposure to a fraction of a second (about 0.25 s). The principal retinal hazard resulting from viewing bright light sources is photoretinitis, e.g., solar retinitis with an accompanying scotoma which results from staring at the sun. Solar retinitis was once referred to as 'eclipse blindness' and associated 'retinal burn'. Only in recent years has it become clear that photoretinitis results from a photochemical injury mechanism following exposure of the retina to shorter wavelengths in the visible spectrum, i.e., violet and blue light. Prior to conclusive animal experiments at that time, it was thought to be a thermal injury mechanism. However, it has been shown conclusively that an intense exposure to short-wavelength light (hereafter referred to as 'blue light') can cause retinal injury. The product of the dose-rate and the exposure duration always must result in the same exposure dose (in joules-per-square centimeter at the retina) to produce a threshold injury. Blue-light retinal injury (photoretinitis) can result from viewing either an extremely bright light for a short time, or a less bright light for longer exposure periods. This characteristic of photochemical injury mechanisms is termed reciprocity and helps to distinguish these effects from thermal burns, where heat conduction requires a very intense exposure within seconds to cause a retinal coagulation otherwise, surrounding tissue conducts the heat away from the retinal image. Injury thresholds for acute injury in experimental animals for both corneal and retinal effects have been corroborated for the human eye from accident data. Occupational safety limits for exposure to UVR and bright light are based upon this

  19. Dynamic transcriptome and phytohormone profiling along the time of light exposure in the mesocotyl of rice seedling.

    PubMed

    Feng, Fangjun; Mei, Hanwei; Fan, Peiqing; Li, Yanan; Xu, Xiaoyan; Wei, Haibin; Yan, Ming; Luo, Lijun

    2017-09-20

    Mesocotyl elongation is an important trait influencing seedling emergence and establishment in rice direct-seeding cultivation and is immediately inhibited after light exposure. Detailed researches on the molecular basis and biological processes underlying light repression of mesocotyl growth could probably provide useful information for key factors controlling this trait. Here we monitored the transcriptome and endogenous phytohormone changes specifically in the elongating mesocotyl in response to light exposure with a time-course. It was revealed that 974 transcripts were significantly differentially expressed (FDR < 0.05, |log2 (L/D) | ≥2) after light exposure. Most of the differential expression genes associated with the responses to hormone. Metabolic pathway analysis using the KEGG system suggested plant hormone signal transduction, α-linolenic acid metabolism and diterpenoid biosynthesis were critical processes of mesocotyl growth inhibited by light. Consistent with DEGs, the endogenous IAA, tZ and GA3 content was significantly reduced while JA level was dramatically increased, which indicated that light inhibited rice mesocotyl growth through decreasing IAA, tZ and GA3 content and/or increasing JA level. The present results enriched our knowledge about the genes and phytohormones regulating mesocotyl elongation in rice, which may help improve future studies on associated genes and develop new varieties tolerance to deep sowing.

  20. Fingerprints in the Light

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Figure 1

    This graph, or spectrum, shows the light from a dusty, distant galaxy located 11 billion light-years away. The galaxy is invisible to optical telescopes, but NASA's Spitzer Space Telescope was able to capture the light from it and dozens of other similar galaxies using heat-seeking infrared eyes.

    Spectra are created when an instrument called a spectrograph spreads light out into its basic parts, like a prism turning sunlight into a rainbow. They contain the signatures, or 'fingerprints,' of molecules that contribute to an object's light.

    In this case, the galaxy's spectrum reveals the fingerprint for silicate dust (large dip at right), a planetary building block like sand, only smaller. This particular fingerprint is important because it helped astronomers determine how far away the galaxy lies, or more specifically, how much the galaxy's light had stretched, or 'redshifted,' during its journey to Spitzer's eyes. Because the universe is expanding, a galaxy's light will shift toward reddish wavelengths as it moves away from us. This galaxy was found to have a redshift of 1.95, which means that its light took about 11 billion years to get here.

    The presence of the silicate fingerprint is also significant because it implies that galaxies were ripe for planetary formation 11 billion years ago - back to a time when the universe was 3 billion years old. The universe is currently believed to be 13.5 billion years old. This is the furthest back in time that silicate dust has been detected around a galaxy.

    These data were taken by Spitzer's infrared spectrograph in July, 2004.

  1. Cauldron of Light

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on image to view the animation

    In this animation, a seething cauldron of light appears to bubble and ooze around the remains of a giant star that astronomers have been watching tear itself apart for the last 300 years. This movie flips quickly between different observations taken over three years by NASA's Spitzer Space Telescope.

    Beginning in the center, the well-studied Cassiopeia A supernova remnant is shown. Cassiopeia A is the remnant of a once massive star that died in a violent supernova explosion. It consists of a dead star, called a neutron star, and a surrounding shell of material that was blasted off as the star died.

    Panning outward, 'light echoes' create the illusion of motion in the clouds, as different areas of the material are lit up in succession by the light flash of the supernova. A light echo occurs when a star explodes, acting like a cosmic flashbulb. The light from this explosion zips through nearby dust clumps, illuminating and heating them up slightly. This brief period of warming causes them to glow in infrared, like a chain of Christmas bulbs lighting up one by one. The result is an optical illusion, in which the dust appears to be flying outward at the speed of light.

    In reality, the clouds are stationary, at least in the brief time over which these observations were taken. The inclination of the clouds cause some light echoes to appear to expand away from the supernova remnant, while others move towards it or boil in many directions with seeming turbulence.

  2. Solid state lighting component

    DOEpatents

    Keller, Bernd; Ibbetson, James; Tarsa, Eric; Negley, Gerald; Yuan, Thomas

    2012-07-10

    An LED component comprising an array of LED chips mounted on a planar surface of a submount with the LED chips capable of emitting light in response to an electrical signal. The LED chips comprise respective groups emitting at different colors of light, with each of the groups interconnected in a series circuit. A lens is included over the LED chips. Other embodiments can comprise thermal spreading structures included integral to the submount and arranged to dissipate heat from the LED chips.

  3. Solid state lighting component

    DOEpatents

    Yuan, Thomas; Keller, Bernd; Ibbetson, James; Tarsa, Eric; Negley, Gerald

    2010-10-26

    An LED component comprising an array of LED chips mounted on a planar surface of a submount with the LED chips capable of emitting light in response to an electrical signal. The LED chips comprise respective groups emitting at different colors of light, with each of the groups interconnected in a series circuit. A lens is included over the LED chips. Other embodiments can comprise thermal spreading structures included integral to the submount and arranged to dissipate heat from the LED chips.

  4. Fingerprints in the Light

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Figure 1

    This graph, or spectrum, shows the light from a dusty, distant galaxy located 11 billion light-years away. The galaxy is invisible to optical telescopes, but NASA's Spitzer Space Telescope was able to capture the light from it and dozens of other similar galaxies using heat-seeking infrared eyes.

    Spectra are created when an instrument called a spectrograph spreads light out into its basic parts, like a prism turning sunlight into a rainbow. They contain the signatures, or 'fingerprints,' of molecules that contribute to an object's light.

    In this case, the galaxy's spectrum reveals the fingerprint for silicate dust (large dip at right), a planetary building block like sand, only smaller. This particular fingerprint is important because it helped astronomers determine how far away the galaxy lies, or more specifically, how much the galaxy's light had stretched, or 'redshifted,' during its journey to Spitzer's eyes. Because the universe is expanding, a galaxy's light will shift toward reddish wavelengths as it moves away from us. This galaxy was found to have a redshift of 1.95, which means that its light took about 11 billion years to get here.

    The presence of the silicate fingerprint is also significant because it implies that galaxies were ripe for planetary formation 11 billion years ago - back to a time when the universe was 3 billion years old. The universe is currently believed to be 13.5 billion years old. This is the furthest back in time that silicate dust has been detected around a galaxy.

    These data were taken by Spitzer's infrared spectrograph in July, 2004.

  5. Signal-light nomogram

    NASA Technical Reports Server (NTRS)

    Gordon, J. I.; Edgerton, C. F.; Duntley, S. Q.

    1975-01-01

    A nomogram is presented for predicting the sighting range for white, steady-burning signal lights. The theoretical and experimental bases are explained and instructions are provided for its use for a variety of practical problems concerning the visibility of signal lights. The nomogram is appropriate for slant path as well as horizontal sightings, and the gain of range achieved by utilizing binoculars can be predicted by use of it.

  6. Cauldron of Light

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on image to view the animation

    In this animation, a seething cauldron of light appears to bubble and ooze around the remains of a giant star that astronomers have been watching tear itself apart for the last 300 years. This movie flips quickly between different observations taken over three years by NASA's Spitzer Space Telescope.

    Beginning in the center, the well-studied Cassiopeia A supernova remnant is shown. Cassiopeia A is the remnant of a once massive star that died in a violent supernova explosion. It consists of a dead star, called a neutron star, and a surrounding shell of material that was blasted off as the star died.

    Panning outward, 'light echoes' create the illusion of motion in the clouds, as different areas of the material are lit up in succession by the light flash of the supernova. A light echo occurs when a star explodes, acting like a cosmic flashbulb. The light from this explosion zips through nearby dust clumps, illuminating and heating them up slightly. This brief period of warming causes them to glow in infrared, like a chain of Christmas bulbs lighting up one by one. The result is an optical illusion, in which the dust appears to be flying outward at the speed of light.

    In reality, the clouds are stationary, at least in the brief time over which these observations were taken. The inclination of the clouds cause some light echoes to appear to expand away from the supernova remnant, while others move towards it or boil in many directions with seeming turbulence.

  7. Simple Schlieren Light Meter

    NASA Technical Reports Server (NTRS)

    Rhodes, David B.; Franke, John M.; Jones, Stephen B.; Leighty, Bradley D.

    1992-01-01

    Simple light-meter circuit used to position knife edge of schlieren optical system to block exactly half light. Enables operator to check quickly position of knife edge between tunnel runs to ascertain whether or not in alignment. Permanent measuring system made part of each schlieren system. If placed in unused area of image plane, or in monitoring beam from mirror knife edge, provides real-time assessment of alignment of schlieren system.

  8. Solid state lighting component

    DOEpatents

    Yuan, Thomas; Keller, Bernd; Ibbetson, James; Tarsa, Eric; Negley, Gerald

    2015-07-07

    An LED component comprising an array of LED chips mounted on a planar surface of a submount with the LED chips capable of emitting light in response to an electrical signal. The LED chips comprise respective groups emitting at different colors of light, with each of the groups interconnected in a series circuit. A lens is included over the LED chips. Other embodiments can comprise thermal spreading structures included integral to the submount and arranged to dissipate heat from the LED chips.

  9. Organic light emitting diode with light extracting electrode

    DOEpatents

    Bhandari, Abhinav; Buhay, Harry

    2017-04-18

    An organic light emitting diode (10) includes a substrate (20), a first electrode (12), an emissive active stack (14), and a second electrode (18). At least one of the first and second electrodes (12, 18) is a light extracting electrode (26) having a metallic layer (28). The metallic layer (28) includes light scattering features (29) on and/or in the metallic layer (28). The light extracting features (29) increase light extraction from the organic light emitting diode (10).

  10. Conversion of orange light into blue light.

    PubMed

    Rai, Nirupama; Jha, Y; Kamal, K P; Kumar, S; Rai, V K

    2010-08-01

    Frequency upconversion in triply ionized praseodymium doped glass with composition TeO(2)-Na(2)O (TNO) system under the excitation with a laser light from a dye laser has been reported and the covalency, bonding parameter, nephalauxetic effect which provides the information about the nature of bonding between the lanthanide ions and the surrounding oxygens for the present glassy material calculated. The energy transfer route followed by the two excited praseodymium ions is observed to be the leading process for the upconversion emission.

  11. [Bright light therapy].

    PubMed

    Poirrier, R; Cambron, L

    2007-01-01

    Bright light therapy is a treatment that emerged in the eighties of the last century. It can be used in different pathologies such as seasonal affective disorders, major depressions, and many disorders of the wake-sleep rhythm, whether they are of primary or secondary origin. Important progress made at the basic neuroscience levels, allows today a sound understanding of the bright light mode of action. Moreover, the main indications are now the subject of consensus reports and meta-analyses which show good levels of evidence-based medicine. Bright light therapy constitutes a first choice indication in seasonal affective disorder. It is also perfectly possible to prescribe bright light therapy in the major depression disorders. It has been demonstrated that the effect size is the same as with antidepressants of reference. It is admitted nowadays that bright light therapy may be at least, an adjunct to pharmacotherapy, in order to accelerate the antidepressant effect onset, or to prolong this effect after withdrawal of the drug. Bright light therapy can also be viewed as an alternative to the pharmacological approach especially when this one is impossible, not tolerated or not accepted by the patient. The contraindications are rare.

  12. Fifth generation light sources

    NASA Astrophysics Data System (ADS)

    Romaniuk, Ryszard S.

    2016-12-01

    Coherent light sources are one of the most fundamental research tools in biology, technology and in other areas. Synchrotron light source consists of a few basic parts: energy source - which is an electron beam accelerator, energy converter between electron and photon beams - which is an undulator, and photon user experimental lines. Each of these parts is separately a complex system, which is currently a subject to fast technological development. Future light sources of the fifth generation are based on completely new solutions of these fundamental parts, in comparison with the sources of the previous generations. Energy source is a new generation laser - plasma accelerator with electrical field in the area of multiple GV/m. A miniature undulator is tested in the MEMS technology from new materials. Classical light beam lines, vacuum, and difficult for management and beam distribution, change their meaning in the case of availability of miniature undulators positioned immediately at or even inside the experimental stations. After an introduction concerning the light sources of the previous generations, the article shows current research efforts on the mentioned key components of the fifth generation light sources. In some cases this is a continuation and modernization of the previous technologies, in the majority it is a brave endeavour to apply completely new technologies, like laser - plasma acceleration.

  13. Earth's City Lights

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image of Earth's city lights was created with data from the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS). Originally designed to view clouds by moonlight, the OLS is also used to map the locations of permanent lights on the Earth's surface. The brightest areas of the Earth are the most urbanized, but not necessarily the most populated. (Compare western Europe with China and India.) Cities tend to grow along coastlines and transportation networks. Even without the underlying map, the outlines of many continents would still be visible. The United States interstate highway system appears as a lattice connecting the brighter dots of city centers. In Russia, the Trans-Siberian railroad is a thin line stretching from Moscow through the center of Asia to Vladivostok. The Nile River, from the Aswan Dam to the Mediterranean Sea, is another bright thread through an otherwise dark region. Even more than 100 years after the invention of the electric light, some regions remain thinly populated and unlit. Antarctica is entirely dark. The interior jungles of Africa and South America are mostly dark, but lights are beginning to appear there. Deserts in Africa, Arabia, Australia, Mongolia, and the United States are poorly lit as well (except along the coast), along with the boreal forests of Canada and Russia, and the great mountains of the Himalaya. The Earth Observatory article Bright Lights, Big City describes how NASA scientists use city light data to map urbanization. Image by Craig Mayhew and Robert Simmon, NASA GSFC, based on DMSP data

  14. Light Sources 2007

    NASA Astrophysics Data System (ADS)

    Liu, M. Q.; Devonshire, R.

    2007-04-01

    This volume contains the proceedings of the 11th International Symposium on the Science and Technology of Light Sources (LS:11) held in Fudan University, Shanghai, China in the period May 20th to 24th, 2007. In the 32 years since the first symposium was held in Loughborough, UK, the LS series has established itself as the major international event which brings together on a regular basis the world's leading scientists and engineers involved in the research and development of light source technologies. The participants come from the R&D laboratories of the world’s leading light source manufacturing companies and from research groups in universities, government laboratories and research institutes. The highly multi-disciplinary nature of the field results in a unique mix of physicists, chemists, chemical physicists, materials scientists and electrical, electronic and mechanical engineers attending the symposia. The more than 250 papers in these LS:11 proceedings provide an excellent overview of the current status of light source science and technology. The energy efficiency and light emission characteristics of existing technologies continue to be improved, solid state technologies are advancing rapidly and innovation flourishes generally. Audience Professional scientists and engineers involved in light source related R&D. Postgraduate-level students in the physical sciences, applied mathematics, materials science, and electrical and electronic engineering. The contents will also be of interest to anyone with a background in science and engineering wishing to gain an overview of current activity in this important global industry and research field.

  15. High-Rate Mechanical Properties of JA2 Propellant at Temperatures from -50 to 80 deg C

    DTIC Science & Technology

    2015-07-01

    Proving Ground (MD): Army Research Laboratory (US); 2005 Jul. Report No.: ARL-TR-3546. 11. Hoffman HJ. Uniaxial compressive gun propellant test. In: Solid ...ARL-MR-0894 ● JULY 2015 US Army Research Laboratory High-Rate Mechanical Properties of JA2 Propellant at Temperatures from –50...Research Laboratory High-Rate Mechanical Properties of JA2 Propellant at Temperatures from –50 to 80 °C by Stephen L Howard, Michael G Leadore

  16. Light Pollution and Wildlife

    NASA Astrophysics Data System (ADS)

    Duffek, J.

    2008-12-01

    for Educational Program IYA Dark Skies Education Session Fall American Geophysical Union San Francisco, December 15-19, 2008 Light Pollution and Wildlife This is a very exciting time to be a part of the mission to keep the nighttime skies natural. The International Year of Astronomy (IYA) 2009 is developing programs for all areas of Dark Skies Awareness. For many years the issue of light pollution focused on the impact to the astronomy industry. While this is an important area, research has shown that light pollution negatively impacts wildlife, their habitat, human health, and is a significant waste of energy. Since the message and impact of the effects of light pollution are much broader now, the message conveyed to the public must also be broader. Education programs directed at youth are a new frontier to reach out to a new audience about the adverse effects of too much artificial light at night. The International Dark-Sky Association (IDA) has developed educational presentations using the National Science Teachers Association Education Standards. These programs focus on youth between the ages of 5 to 17exploring new territory in the education of light pollution. The IDA education programs are broken down into three age groups; ages 5-9, 8-13, 12 and older. The presentations come complete with PowerPoint slides, discussion notes for each slide, and workbooks including age appropriate games to keep young audiences involved. A new presentation reflects the growing area of interest regarding the effects of too much artificial light at night on wildlife. This presentation outlines the known problems for ecosystems caused by artificial light at night. Insects are attracted to artificial lights and may stay near that light all night. This attraction interferes with their ability to migrate, mate, and look for food. Such behavior leads to smaller insect populations. Fewer insects in turn affect birds and bats, because they rely on insects as a food source. The IDA

  17. Nonclassical light in interferometric measurements

    NASA Technical Reports Server (NTRS)

    Ansari, N. A.; Difiore, L.; Romano, R.; Solimeno, S.; Zaccaria, F.; Manko, Margarita A.; Manko, Vladimir I.

    1995-01-01

    It is shown that the even and odd coherent light and other nonclassical states of light like superposition of coherent states with different phases may replace the squeezed light in an interferometric gravitational wave detector to increase its sensitivity.

  18. The crosstalk between Target of Rapamycin (TOR) and Jasmonic Acid (JA) signaling existing in Arabidopsis and cotton

    PubMed Central

    Song, Yun; Zhao, Ge; Zhang, Xueyan; Li, Linxuan; Xiong, Fangjie; Zhuo, Fengping; Zhang, Chaojun; Yang, Zuoren; Datla, Raju; Ren, Maozhi; Li, Fuguang

    2017-01-01

    Target of rapamycin (TOR) acts as an important regulator of cell growth, development and stress responses in most examined diploid eukaryotes. However, little is known about TOR in tetraploid species such as cotton. Here, we show that TORC1-S6K-RPS6, the major signaling components, are conserved and further expanded in cotton genome. Though the cotton seedlings are insensitive to rapamycin, AZD8055, the second-generation inhibitor of TOR, can significantly suppress the growth in cotton. Global transcriptome analysis revealed that genes associated with jasmonic acid (JA) biosynthesis and transduction were significantly altered in AZD8055 treated cotton seedlings, suggesting the potential crosstalk between TOR and JA signaling. Pharmacological and genetic approaches have been employed to get further insights into the molecular mechanism of the crosstalk between TOR and JA. Combination of AZD8055 with methyl jasmonate can synergistically inhibit cotton growth, and additionally JA levels were significantly increased when cotton seedlings were subjected to AZD8055. JA biosynthetic and signaling mutants including jar1, coi1-2 and myc2-2 displayed TOR inhibitor-resistant phenotypes, whereas COI1 overexpression transgenic lines and jaz10 exhibited sensitivity to AZD8055. Consistently, cotton JAZ can partially rescue TOR-suppressed phenotypes in Arabidopsis. These evidences revealed that the crosstalk between TOR and JA pathway operates in cotton and Arabidopsis. PMID:28374843

  19. The crosstalk between Target of Rapamycin (TOR) and Jasmonic Acid (JA) signaling existing in Arabidopsis and cotton.

    PubMed

    Song, Yun; Zhao, Ge; Zhang, Xueyan; Li, Linxuan; Xiong, Fangjie; Zhuo, Fengping; Zhang, Chaojun; Yang, Zuoren; Datla, Raju; Ren, Maozhi; Li, Fuguang

    2017-04-04

    Target of rapamycin (TOR) acts as an important regulator of cell growth, development and stress responses in most examined diploid eukaryotes. However, little is known about TOR in tetraploid species such as cotton. Here, we show that TORC1-S6K-RPS6, the major signaling components, are conserved and further expanded in cotton genome. Though the cotton seedlings are insensitive to rapamycin, AZD8055, the second-generation inhibitor of TOR, can significantly suppress the growth in cotton. Global transcriptome analysis revealed that genes associated with jasmonic acid (JA) biosynthesis and transduction were significantly altered in AZD8055 treated cotton seedlings, suggesting the potential crosstalk between TOR and JA signaling. Pharmacological and genetic approaches have been employed to get further insights into the molecular mechanism of the crosstalk between TOR and JA. Combination of AZD8055 with methyl jasmonate can synergistically inhibit cotton growth, and additionally JA levels were significantly increased when cotton seedlings were subjected to AZD8055. JA biosynthetic and signaling mutants including jar1, coi1-2 and myc2-2 displayed TOR inhibitor-resistant phenotypes, whereas COI1 overexpression transgenic lines and jaz10 exhibited sensitivity to AZD8055. Consistently, cotton JAZ can partially rescue TOR-suppressed phenotypes in Arabidopsis. These evidences revealed that the crosstalk between TOR and JA pathway operates in cotton and Arabidopsis.

  20. Differential Expression of Carotenogenic Genes, Associated Changes on Astaxanthin Production and Photosynthesis Features Induced by JA in H. pluvialis

    PubMed Central

    Zhang, Xiaowen; Xu, Dong; Zhao, Yuefeng; Wang, Yitao; Lv, Hongxin; Liming Yang; Chen, Lingling; Ye, Naihao

    2012-01-01

    Haematococcus pluvialis is an organism that under certain conditions can produce astaxanthin, an economically important carotenoid. In this study, the transcriptional expression patterns of eight carotenogenic genes of H. pluvialis in response to jasmonic acid (JA) were evaluated using real-time PCR. Astaxanthin accumulation action and photosynthesis flourescence were monitored at the same time. The results showed all eight genes exhibited higher transcriptional expression significantly under JA treatments. JA25 (25 mg/L) induction had greater effect (>10-fold up-regulation) on the transcriptional expression of pds, crtR-B and lyc than on ipi-1, ipi-2, psy, bkt2, and crtO. JA50 (50 mg/L) treatment had greater impact on the transcriptional expression of ipi-1, ipi-2, psy, crtR-B and crtO than on pds, lyc and bkt2. Astaxanthin biosynthesis in the presence of JA appeared to be up-regulated mainly by psy, pds, crtR-B, lyc, bkt2 and crtO at the transcriptional level and ipi-1, ipi-2 at both transcriptional and post-transcriptional levels. Under JA induction, the photosynthetic efficiency [Y (II)] and the maximum quantum efficiency of PS II (Fv/Fm) decreased significantly, but the non-photochemical quenching of chlorophyll fluorescence (NPQ) increased drastically with the accumulation of astaxanthin. PMID:22870309

  1. Light diffusing fiber optic chamber

    DOEpatents

    Maitland, Duncan J.

    2002-01-01

    A light diffusion system for transmitting light to a target area. The light is transmitted in a direction from a proximal end to a distal end by an optical fiber. A diffusing chamber is operatively connected to the optical fiber for transmitting the light from the proximal end to the distal end and transmitting said light to said target area. A plug is operatively connected to the diffusing chamber for increasing the light that is transmitted to the target area.

  2. Light pipe - design for efficiency

    SciTech Connect

    Hockey, S.N.

    1985-08-01

    The high cost and availability of materials which are clear enough to transmit light without absorption has limited the idea of piping large-scale quantities of light. The light pipe uses the principle of Total Internal Reflection, with the light guided by very accurate prisms. The transmission of light directed into the end of a Light Pipe at an angle of less than 27.6 degrees is theoretically 100% efficient. The author describes its uses and advantages for lighting offices, cold storage areas, difficult access and hazardous areas, and for solar lighting. Future directions will be to improve the economics and accuracy of the technology. 4 references, 2 figures.

  3. Indoor Lighting Facilities

    NASA Astrophysics Data System (ADS)

    Matsushima, Koji; Saito, Yoshinori; Ichikawa, Shigenori; Kawauchi, Takao; Tanaka, Tsuneo; Hirano, Rika; Tazuke, Fuyuki

    According to the statistics on building construction floor area from the Ministry of Land, Infrastructure, Transport and Tourism, the total floor area of building construction started in Japan in 2007 was 160,991 thousand square meters, or 14.8% less than the area of the previous year, and the reduction was the first reduction in the past five years. The office markets in Tokyo and Nagoya were active, as represented by the supplies of skyscrapers, and energy saving measures, such as the adoption of high efficiency lighting equipment, the control for initial stage illuminance, daylight harvesting, and the use of occupancy sensors, were well established. In the field of public construction, including museums, multi-purpose halls, and religious buildings, the total area of the new construction was 10.8% less than the total for the previous year, and this reduction was a continuation of an eleven-year trend. In spaces with high ceiling, the innovation for easy replacement of light sources used with reflection mirror systems and optical fibers was noted. Hospitals adapted to the expectation for improved services in their selection of lighting facilities to improve the residential environment for patients while taking into consideration the needs of the aging population, by their use of devices in corridors to help maintain a continuity of light. In libraries, a pendant system was developed to illuminate both ceilings and book shelves. In the field of theaters and halls, the time limit for repairing existing systems had come for the large facilities that were opened during the theater and hall construction boom of the 1960s through 1980s, and around 26 renovations were done. Almost all the renovations were conversions to intelligent dimming systems and lighting control desks. In the field of stores and commercial facilities, the atmosphere and glitter of the selling floor was produced by new light sources, such as ceramic metal halide lamps and LEDs, which have high

  4. Biomaterials in light amplification

    NASA Astrophysics Data System (ADS)

    Mysliwiec, Jaroslaw; Cyprych, Konrad; Sznitko, Lech; Miniewicz, Andrzej

    2017-03-01

    Biologically produced or inspired materials can serve as optical gain media, i.e. they can exhibit the phenomenon of light amplification. Some of these materials, under suitable dye-doping and optical pumping conditions, show lasing phenomena. The emerging branch of research focused on obtaining lasing action in highly disordered and highly light scattering materials, i.e. research on random lasing, is perfectly suited for biological materials. The use of biomaterials in light amplification has been extensively reported in the literature. In this review we attempt to report on progress in the development of biologically derived systems able to show the phenomena of light amplification and random lasing together with the contribution of our group to this field. The rich world of biopolymers modified with molecular aggregates and nanocrystals, and self-organized at the nanoscale, offers a multitude of possibilities for tailoring luminescent and light scattering properties that are not easily replicated in conventional organic or inorganic materials. Of particular importance and interest are light amplification and lasing, or random lasing studies in biological cells and tissues. In this review we will describe nucleic acids and their complexes employed as gain media due to their favorable optical properties and ease of manipulation. We will report on research conducted on various biomaterials showing structural analogy to nucleic acids such as fluorescent proteins, gelatins in which the first distributed feedback laser was realized, and also amyloids or silks, which, due to their dye-doped fiber-like structure, allow for light amplification. Other materials that were investigated in that respect include polysaccharides, like starch exhibiting favorable photostability in comparison to other biomaterials, and chitosan, which forms photonic crystals or cellulose. Light amplification and random lasing was not only observed in processed biomaterials but also in living

  5. Laser light scattering review

    NASA Technical Reports Server (NTRS)

    Schaetzel, Klaus

    1989-01-01

    Since the development of laser light sources and fast digital electronics for signal processing, the classical discipline of light scattering on liquid systems experienced a strong revival plus an enormous expansion, mainly due to new dynamic light scattering techniques. While a large number of liquid systems can be investigated, ranging from pure liquids to multicomponent microemulsions, this review is largely restricted to applications on Brownian particles, typically in the submicron range. Static light scattering, the careful recording of the angular dependence of scattered light, is a valuable tool for the analysis of particle size and shape, or of their spatial ordering due to mutual interactions. Dynamic techniques, most notably photon correlation spectroscopy, give direct access to particle motion. This may be Brownian motion, which allows the determination of particle size, or some collective motion, e.g., electrophoresis, which yields particle mobility data. Suitable optical systems as well as the necessary data processing schemes are presented in some detail. Special attention is devoted to topics of current interest, like correlation over very large lag time ranges or multiple scattering.

  6. MEMS Incandescent Light Source

    NASA Technical Reports Server (NTRS)

    Tuma, Margaret; King, Kevin; Kim, Lynn; Hansler, Richard; Jones, Eric; George, Thomas

    2001-01-01

    A MEMS-based, low-power, incandescent light source is being developed. This light source is fabricated using three bonded chips. The bottom chip consists of a reflector on Silicon, the middle chip contains a Tungsten filament bonded to silicon and the top layer is a transparent window. A 25-micrometer-thick spiral filament is fabricated in Tungsten using lithography and wet-etching. A proof-of-concept device has been fabricated and tested in a vacuum chamber. Results indicate that the filament is electrically heated to approximately 2650 K. The power required to drive the proof-of-concept spiral filament to incandescence is 1.25 W. The emitted optical power is expected to be approximately 1.0 W with the spectral peak at 1.1 microns. The micromachining techniques used to fabricate this light source can be applied to other MEMS devices.

  7. Pupillary efficient lighting system

    SciTech Connect

    Berman, S.M.; Jewett, D.L.

    1991-05-14

    This patent describes a lighting system having at least two independent lighting subsystems each with a different ratio of scotopic illumination to photopic illumination. The radiant energy in the visible region of the spectrum of the lighting subsystems can be adjusted relative to each other so that the total scotopic illumination of the combined system and the total photopic illumination of the combined system can be varied independently. The dilation or contraction of the pupil of an eye is controlled by the level of scotopic illumination and because the scotopic and photopic illumination can be separately controlled, the system allows the pupil size to be varied independently of the level of photopic illumination. Hence, the vision process can be improved for a given level of photopic illumination.

  8. 3D light robotics

    NASA Astrophysics Data System (ADS)

    Glückstad, Jesper; Palima, Darwin; Villangca, Mark; Banas, Andrew

    2016-04-01

    As celebrated by the Nobel Prize 2014 in Chemistry light-based technologies can now overcome the diffraction barrier for imaging with nanoscopic resolution by so-called super-resolution microscopy1. However, interactive investigations coupled with advanced imaging modalities at these small scale domains gradually demand the development of a new generation of disruptive tools, not only for passively observing at nanoscopic scales, but also for actively reaching into and effectively handling constituents in this size domain. This intriguing mindset has recently led to the emergence of a novel research discipline that could potentially be able to offer the full packet needed for true "active nanoscopy" by use of so-called light-driven micro-robotics or Light Robotics in short.

  9. Slow light beam splitter.

    PubMed

    Xiao, Yanhong; Klein, Mason; Hohensee, Michael; Jiang, Liang; Phillips, David F; Lukin, Mikhail D; Walsworth, Ronald L

    2008-07-25

    We demonstrate a slow light beam splitter using rapid coherence transport in a wall-coated atomic vapor cell. We show that particles undergoing random and undirected classical motion can mediate coherent interactions between two or more optical modes. Coherence, written into atoms via electromagnetically induced transparency using an input optical signal at one transverse position, spreads out via ballistic atomic motion, is preserved by an antirelaxation wall coating, and is then retrieved in outgoing slow light signals in both the input channel and a spatially-separated second channel. The splitting ratio between the two output channels can be tuned by adjusting the laser power. The slow light beam splitter may improve quantum repeater performance and be useful as an all-optical dynamically reconfigurable router.

  10. Sneaky light stop

    DOE PAGES

    Eifert, Till; Nachman, Benjamin

    2015-02-20

    A light supersymmetric top quark partner (stop) with a mass nearly degenerate with that of the standard model (SM) top quark can evade direct searches. The precise measurement of SM top properties such as the cross-section has been suggested to give a handle for this ‘stealth stop’ scenario. We present an estimate of the potential impact a light stop may have on top quark mass measurements. The results indicate that certain light stop models may induce a bias of up to a few GeV, and that this effect can hide the shift in, and hence sensitivity from, cross-section measurements. Duemore » to the different initial states, the size of the bias is slightly different between the LHC and the Tevatron. The studies make some simplifying assumptions for the top quark measurement technique, and are based on truth-level samples.« less

  11. Sneaky light stop

    SciTech Connect

    Eifert, Till; Nachman, Benjamin

    2015-04-01

    A light supersymmetric top quark partner (stop) with a mass nearly degenerate with that of the standard model (SM) top quark can evade direct searches. The precise measurement of SM top properties such as the cross-section has been suggested to give a handle for this ‘stealth stop’ scenario. We present an estimate of the potential impact a light stop may have on top quark mass measurements. The results indicate that certain light stop models may induce a bias of up to a few GeV, and that this effect can hide the shift in, and hence sensitivity from, cross-section measurements. Due to the different initial states, the size of the bias is slightly different between the LHC and the Tevatron. The studies make some simplifying assumptions for the top quark measurement technique, and are based on truth-level samples.

  12. Sneaky light stop

    SciTech Connect

    Eifert, Till; Nachman, Benjamin

    2015-02-20

    A light supersymmetric top quark partner (stop) with a mass nearly degenerate with that of the standard model (SM) top quark can evade direct searches. The precise measurement of SM top properties such as the cross-section has been suggested to give a handle for this ‘stealth stop’ scenario. We present an estimate of the potential impact a light stop may have on top quark mass measurements. The results indicate that certain light stop models may induce a bias of up to a few GeV, and that this effect can hide the shift in, and hence sensitivity from, cross-section measurements. Due to the different initial states, the size of the bias is slightly different between the LHC and the Tevatron. The studies make some simplifying assumptions for the top quark measurement technique, and are based on truth-level samples.

  13. Light harvesting arrays

    DOEpatents

    Lindsey, Jonathan S.

    2002-01-01

    A light harvesting array useful for the manufacture of devices such as solar cells comprises: (a) a first substrate comprising a first electrode; and (b) a layer of light harvesting rods electrically coupled to the first electrode, each of the light harvesting rods comprising a polymer of Formula I: X.sup.1.paren open-st.X.sup.m+1).sub.m (I) wherein m is at least 1, and may be from two, three or four to 20 or more; X.sup.1 is a charge separation group (and preferably a porphyrinic macrocycle, which may be one ligand of a double-decker sandwich compound) having an excited-state of energy equal to or lower than that of X.sup.2, and X.sup.2 through X.sup.m+1 are chromophores (and again are preferably porphyrinic macrocycles).

  14. Encouragement for lighting victims

    NASA Astrophysics Data System (ADS)

    Mizon, R.

    2001-02-01

    Much of the correspondence I receive (and there's a lot of it) is from people, both astronomers and non-astronomers, who suffer from neighbours' security lighting, and feel that there is nothing that they can do about it, since there is as yet no legislation on light as a nuisance. In some cases, people's quality of life is affected to the extent that they have had to change living patterns, jobs, or even move house. The law of nuisance states that one is entitled to the 'enjoyment of one's property', which includes legitimate pursuits undertaken on that property. Light is not yet(!) a statutory nuisance, but note the use of the word in the judgment below. Here is the story of someone who did do something about it.

  15. Light echoes - Novae

    NASA Technical Reports Server (NTRS)

    Schaefer, Bradley E.

    1988-01-01

    The sudden brilliance of a nova eruption will be reflected on surrounding dust grains to create a phantom nebula. Previous searches for these light echoes have used relatively short exposures with photograhic detectors. This paper reports on a search around eight recent novae with long exposures using a CCD camera. Despite an increase of sensitivity by over an order of magnitude, no light echoes were detected. It is found that the average grain density must be less than about 10 to the -9th per cu cm for distances from 0.1 pc to 1000 pc from the novae. The light echo around Nova Persei 1901 was caused by reflection off clouds with grain densities of several times 10 to the -9th per cu cm which are at distances between 0.1 pc and 10 pc. Echoes from dust in a circumstellar shell or ejected during a previous eruption will be effectively unobservable.

  16. High Intensity Lighting

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Nightime illumination is an important part of round-the-clock pre-launch preparations because NASA uses TV and film cameras to monitor each step of the preliminaries and at times to identify the cause of malfunction during countdown. Generating a one billion candlepower beam visible 50 miles away, the lamps developed by Duro-Test Corporation provide daylight quality light that eliminates color distortion in film and TV coverage. The lighting system was first used at Kennedy Space Center in 1968 for the launch of Apollo 8. Modified versions are available in wide range of applications, such as the battery of spotlights with colored filters that light up Niagara Falls, as well as the lamps used in the projectors for the Smithsonian's IMAX Theatre, indoor theatres with supersized screens and outdoor projection systems.

  17. Pupillary efficient lighting system

    DOEpatents

    Berman, Samuel M.; Jewett, Don L.

    1991-01-01

    A lighting system having at least two independent lighting subsystems each with a different ratio of scotopic illumination to photopic illumination. The radiant energy in the visible region of the spectrum of the lighting subsystems can be adjusted relative to each other so that the total scotopic illumination of the combined system and the total photopic illumination of the combined system can be varied independently. The dilation or contraction of the pupil of an eye is controlled by the level of scotopic illumination and because the scotopic and photopic illumination can be separately controlled, the system allows the pupil size to be varied independently of the level of photopic illumination. Hence, the vision process can be improved for a given level of photopic illumination.

  18. Light emitting ceramic device

    DOEpatents

    Valentine, Paul; Edwards, Doreen D.; Walker, Jr., William John; Slack, Lyle H.; Brown, Wayne Douglas; Osborne, Cathy; Norton, Michael; Begley, Richard

    2010-05-18

    A light-emitting ceramic based panel, hereafter termed "electroceramescent" panel, is herein claimed. The electroceramescent panel is formed on a substrate providing mechanical support as well as serving as the base electrode for the device. One or more semiconductive ceramic layers directly overlay the substrate, and electrical conductivity and ionic diffusion are controlled. Light emitting regions overlay the semiconductive ceramic layers, and said regions consist sequentially of a layer of a ceramic insulation layer and an electroluminescent layer, comprised of doped phosphors or the equivalent. One or more conductive top electrode layers having optically transmissive areas overlay the light emitting regions, and a multi-layered top barrier cover comprising one or more optically transmissive non-combustible insulation layers overlay said top electrode regions.

  19. White light emitting diodes

    NASA Astrophysics Data System (ADS)

    Baur, J.; Schlotter, P.; Schneider, J.

    Using blue-emitting GaN LEDs on SiC substrate chips as primary light sources, we have fabricated green, yellow, red and white light emitting diodes (LUCOLEDs). The generation of mixed colors, as turquoise and magenta, is also demonstrated. The underlying physical principle is that of luminescence downconversion (Stokes shift), as typical for organic dye molecules and many inorganic phosphors. For white light generation via the LUCOLED principle, the phosphor Y3Al5O12:Ce3+(4f1) is ideally suited. The optical characteristics of Ce3+(4f1) in Y3Al5O12(YAG) are discussed in detail. Possibilities to "tune" the white color by various substitutions in the garnet lattice are shortly outlined.

  20. Radioluminescent lighting technology

    SciTech Connect

    Not Available

    1990-01-01

    The glow-in-the-dark stereotype that characterizes the popular image of nuclear materials is not accidental. When the French scientist, Henri Becquerel, first discovered radioactivity in 1896, he was interested in luminescence. Radioluminescence, the production of light from a mixture of energetic and passive materials, is probably the oldest practical application of the unstable nucleus. Tritium-based radioluminescent lighting, in spite of the biologically favorable character of the gaseous tritium isotope, was included in the general tightening of environmental and safety regulations. Tritium light manufacturers would have to meet two fundamental conditions: (1) The benefit clearly outweighed the risk, to the extent that even the perceived risk of a skeptical public would be overcome. (2) The need was significant enough that the customer/user would be willing and able to afford the cost of regulation that was imposed both in the manufacture, use and eventual disposal of nuclear materials. In 1981, researchers at Oak Ridge National Laboratory were investigating larger radioluminescent applications using byproduct nuclear material such as krypton-85, as well as tritium. By 1982, it appeared that large source, (100 Curies or more) tritium gas tube, lights might be useful for marking runways and drop zones for military operations and perhaps even special civilian aviation applications. The successful development of this idea depended on making the light bright enough and demonstrating that large gas tube sources could be used and maintained safely in the environment. This successful DOE program is now in the process of being completed and closed-out. Working closely with the tritium light industry, State governments and other Federal agencies, the basic program goals have been achieved. This is a detailed report of what they have learned, proven, and discovered. 91 refs., 29 figs., 5 tabs. (JF)

  1. Neuroendocrine effects of light

    NASA Astrophysics Data System (ADS)

    Reiter, Russel J.

    1991-09-01

    The light/dark cycle to which animals, and possibly humans, are exposed has a major impact on their physiology. The mechanisms whereby specific tissues respond to the light/dark cycle involve the pineal hormone melatonin. The pineal gland, an end organ of the visual system in mammals, produces the hormone melatonin only at night, at which time it is released into the blood. The duration of elevated nightly melatonin provides every tissue with information about the time of day and time of year (in animals that are kept under naturally changing photoperiods). Besides its release in a circadian mode, melatonin is also discharged in a pulsatile manner; the physiological significance, if any, of pulsatile melatonin release remains unknown. The exposure of animals including man to light at night rapidly depresses pineal melatonin synthesis and, therefore, blood melatonin levels drop precipitously. The brightness of light at night required to depress melatonin production is highly species specific. In general, the pineal gland of nocturnally active mammals, which possess rod-dominated retinas, is more sensitive to inhibition by light than is the pineal gland of diurnally active animals (with cone-dominated retinas). Because of the ability of the light/dark cycle to determine melatonin production, the photoperiod is capable of influencing the function of a variety of endocrine and non-endocrine organs. Indeed, melatonin is a ubiquitously acting pineal hormone with its effects on the neuroendocrine system having been most thoroughly investigated. Thus, in nonhuman photoperiodic mammals melatonin regulates seasonal reproduction; in humans also, the indole has been implicated in the control of reproductive physiology.

  2. Nonimaging optics in lighting to reduce light pollution

    NASA Astrophysics Data System (ADS)

    Ricketts, Melissa; Ferry, Jon; Jiang, Lun; Winston, Roland

    2016-09-01

    Light pollution has become a prominent issue, specifically in National Parks such as Yosemite, where visitors go to enjoy the natural `night sky'. In an effort to reduce light pollution, a particularly obtrusive light source has been selected for retrofit. Using nonimaging optics and light emitting diodes (LEDs), light can be controlled to achieve a desired prescribed illumination distribution. This distribution possesses a sharp cut-off such that light leakage is minimal. Nonimaging optical designs are 3D printed, retrofitted into the candidate fixture, and tested in Yosemite National Park. The end goal is to drastically reduce and even eliminate the excess light from sources around the park.

  3. Light-bending nanoparticles.

    PubMed

    Mirin, Nikolay A; Halas, Naomi J

    2009-03-01

    Metallic nanostructures with their geometry-dependent optical resonances are a topic of intense current interest due to their ability to manipulate light in ways not possible with conventional optical materials. A particularly fascinating aspect of these systems is the recently realized possibility of creating optical frequency "magnetic plasmon" responses of comparable magnitude to the "electric plasmon" response. Here we show that Au nanocups at their magnetoinductive resonance have the unique ability to redirect scattered light in a direction dependent on cup orientation, as a true three-dimensional nanoantenna.

  4. Light Microscopy Microscope Experiment

    NASA Image and Video Library

    2016-02-04

    Ground testing for the first confocal Light Microscopy Microscope (LMM) Experiment. Procter and Gamble is working with NASA Glenn scientists to prepare for a study that examines product stabilizers in a microgravity environment. The particles in the tube glow orange because they have been fluorescently tagged with a dye that reacts to green laser lights to allow construction of a 3D image point by point. The experiment, which will be sent to the ISS later this year, will help P&G develop improved product stabilizers to extend shelf life and develop more environmentally friendly packaging.

  5. Lighting and Astronomy

    DTIC Science & Technology

    2009-12-01

    ago. Bright light is becoming a form of advertising. Figure 1. The sky over Mauna Kea , Hawaii, is affected by outdoor lighting in communit ies from...8217 chris Luginbuhl is an astronomer at the US Naval observatory Flagstaff station in Arizona. connie walker is an associate scientist and education...specialist " tf," N"iio".iOpalut-nraronomy Observatory in Arizona and director of both the lnternational Year of Astrono.my , ;il;;;;i; n*ui"n"rt

  6. Light sheet microscopy.

    PubMed

    Weber, Michael; Mickoleit, Michaela; Huisken, Jan

    2014-01-01

    This chapter introduces the concept of light sheet microscopy along with practical advice on how to design and build such an instrument. Selective plane illumination microscopy is presented as an alternative to confocal microscopy due to several superior features such as high-speed full-frame acquisition, minimal phototoxicity, and multiview sample rotation. Based on our experience over the last 10 years, we summarize the key concepts in light sheet microscopy, typical implementations, and successful applications. In particular, sample mounting for long time-lapse imaging and the resulting challenges in data processing are discussed in detail.

  7. Spatial Light Amplifier Modulators

    NASA Technical Reports Server (NTRS)

    Eng, Sverre T.; Olsson, N. Anders

    1992-01-01

    Spatial light amplifier modulators (SLAM's) are conceptual devices that effect two-dimensional spatial modulation in optical computing and communication systems. Unlike current spatial light modulators, these provide gain. Optical processors incorporating SLAM's designed to operate in reflection or transmission mode. Each element of planar SLAM array is optical amplifier - surface-emitting diode laser. Array addressed electrically with ac modulating signals superimposed on dc bias currents supplied to lasers. SLAM device provides both desired modulation and enough optical gain to enable splitting of output signal into many optical fibers without excessive loss of power.

  8. Light metals 1996

    SciTech Connect

    Hale, W.

    1996-10-01

    Light Metals 1996 presents the proceedings of the technical sessions of the TMS Light Metals Committee at the 125th TMS Annual Meeting held in Anaheim, California, February 4--8, 1996. Developments and innovation in the aluminum and reactive metals industries were covered including basic studies as well as their use and fabrication. The topics encompassed ore and its processing, aluminum reduction, carbon technology, casting technology, recycling, reactive metals, separation processes and waste processing. A number of papers involved mathematical modeling while others were about equipment and applications. One hundred and seventy nine papers were processed separately for inclusion on the data base.

  9. Light and Color

    NASA Astrophysics Data System (ADS)

    Overheim, R. Daniel; Wagner, David L.

    1982-08-01

    Equally valuable as a semester course for non-majors or an introduction for general readers, this text uses only a minimum of science and mathematical background to explain the physical principles of light. It emphasizes color: the properties of light and materials that give rise to it, how it is described and analyzed, how it is produced in nature, and how the eye sees it. Also discusses topics such as geometrical and wave optics and color phenomena, such as rainbows, that appear in nature. Learning aids include problems and exercises at the end of each chapter.

  10. [Light and Medicine].

    PubMed

    Lemmer, Björn

    2016-12-01

    There would be no life without light. The rotation of the earth around its axis has introduced the development of biological clocks in all living subjects regulating all functions of the body. The rhythms best described are the 24-hour/circadian and the seasonal rhythms. The rhythmic composition around the body clock has great impact on health and disease, both in diagnostics and treatment. Nowadays, bright light, e.g. in seasonal affective disorder, can be regarded as a drug, being even more effective than selective serotonin reuptake inhibitors.

  11. Tempel Alive with Light

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This spectacular image of comet Tempel 1 was taken 67 seconds after it obliterated Deep Impact's impactor spacecraft. The image was taken by the high-resolution camera on the mission's flyby craft. Scattered light from the collision saturated the camera's detector, creating the bright splash seen here. Linear spokes of light radiate away from the impact site, while reflected sunlight illuminates most of the comet surface. The image reveals topographic features, including ridges, scalloped edges and possibly impact craters formed long ago.

  12. Over-expression of SlJA2 decreased heat tolerance of transgenic tobacco plants via salicylic acid pathway.

    PubMed

    Liu, Zhong-Ming; Yue, Meng-Meng; Yang, Dong-Yue; Zhu, Shao-Bo; Ma, Na-Na; Meng, Qing-Wei

    2017-04-01

    Over-expression of SlJA2 decreased the accumulation of SA, which resulted in significant physiological and gene expression changes in transgenic tobacco plants, leading to the decreased heat tolerance of transgenic tobacco. NAC family, the largest transcription factors in plants, responses to different environmental stimuli. Here, we isolated a typical NAC transcription factor (SlJA2) from tomato and got transgenic tobacco with SlJA2 over-expression. Expression of SlJA2 was induced by heat stress (42 °C), chilling stress (4 °C), drought stress, osmotic stress, abscisic acid, and salicylic acid. Over-expression of SlJA2 decreased the accumulation of salicylic acid by regulating expression of salicylic acid degradation gene under heat stress. Compared to WT plants, stomatal apertures and water loss increased in transgenic plants, and the damage of photosynthetic apparatus and chlorophyll breakdown were more serious in transgenic plants under heat stress. Meanwhile, more H2O2 and O2(·-) were accumulated transgenic plants and proline synthesis was restricted, which resulted in more serious oxidative damage compared to WT. qRT-PCR analysis showed that over-expression of SlJA2 could down-regulate genes involved in reactive oxygen species scavenging, proline biosynthesis, and response to heat stress. All the above results indicated that SlJA2 may be a negative regulator responded to plant's heat tolerance. Thus, this study provides new insight into roles of NAC family member in plant response to abiotic stress.

  13. Priming for JA-dependent defenses using hexanoic acid is an effective mechanism to protect Arabidopsis against B. cinerea.

    PubMed

    Kravchuk, Zhana; Vicedo, Begonya; Flors, Víctor; Camañes, Gemma; González-Bosch, Carmen; García-Agustín, Pilar

    2011-03-01

    Soil drench treatments with hexanoic acid can effectively protect Arabidopsis plants against Botrytis cinerea through a mechanism based on a stronger and faster accumulation of JA-dependent defenses. Plants impaired in ethylene, salicylic acid, abscisic acid or glutathion pathways showed intact protection by hexanoic acid upon B. cinerea infection. Accordingly, no significant changes in the SA marker gene PR-1 in either the SA or ABA hormone balance were observed in the infected and treated plants. In contrast, the JA signaling pathway showed dramatic changes after hexanoic acid treatment, mainly when the pathogen was present. The impaired JA mutants, jin1-2 and jar1, were unable to display hexanoic acid priming against the necrotroph. In addition, hexanoic acid-treated plants infected with B. cinerea showed priming in the expression of the PDF1.2, PR-4 and VSP1 genes implicated in the JA pathways. Moreover, JA and OPDA levels were primed at early stages by hexanoic acid. Treatments also stimulated increased callose accumulation in response to the pathogen. Although callose accumulation has proved an effective IR mechanism against B. cinerea, it is apparently not essential to express hexanoic acid-induced resistance (HxAc-IR) because the mutant pmr4.1 (callose synthesis defective mutant) is protected by treatment. We recently described how hexanoic acid treatments can protect tomato plants against B. cinerea by stimulating ABA-dependent callose deposition and by priming OPDA and JA-Ile production. We clearly demonstrate here that Hx-IR is a dependent plant species, since this acid protects Arabidopsis plants against the same necrotroph by priming JA-dependent defenses without enhancing callose accumulation.

  14. Light therapies for acne.

    PubMed

    Barbaric, Jelena; Abbott, Rachel; Posadzki, Pawel; Car, Mate; Gunn, Laura H; Layton, Alison M; Majeed, Azeem; Car, Josip

    2016-09-27

    Acne vulgaris is a very common skin problem that presents with blackheads, whiteheads, and inflamed spots. It frequently results in physical scarring and may cause psychological distress. The use of oral and topical treatments can be limited in some people due to ineffectiveness, inconvenience, poor tolerability or side-effects. Some studies have suggested promising results for light therapies. To explore the effects of light treatment of different wavelengths for acne. We searched the following databases up to September 2015: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase and LILACS. We searched ISI Web of Science and Dissertation Abstracts International (from inception). We also searched five trials registers, and grey literature sources. We checked the reference lists of studies and reviews and consulted study authors and other experts in the field to identify further references to relevant randomised controlled trials (RCTs). We updated these searches in July 2016 but these results have not yet been incorporated into the review. We included RCTs of light for treatment of acne vulgaris, regardless of language or publication status. We used standard methodological procedures expected by Cochrane. We included 71 studies, randomising a total of 4211 participants.Most studies were small (median 31 participants) and included participants with mild to moderate acne of both sexes and with a mean age of 20 to 30 years. Light interventions differed greatly in wavelength, dose, active substances used in photodynamic therapy (PDT), and comparator interventions (most commonly no treatment, placebo, another light intervention, or various topical treatments). Numbers of light sessions varied from one to 112 (most commonly two to four). Frequency of application varied from twice daily to once monthly.Selection and performance bias were unclear in the majority of studies. Detection bias was unclear for participant-assessed outcomes and low for investigator

  15. Freeform reflectors for architectural lighting.

    PubMed

    Zhu, Ruidong; Hong, Qi; Zhang, Hongxia; Wu, Shin-Tson

    2015-12-14

    We propose an improved method to design freeform reflectors for architectural lighting: one for accent lighting and another for large area wall washing. The designed freeform reflectors effectively distribute light fluxes over the target surfaces, and generate appropriate illumination patterns for comfortable visual environments, which provides greater flexibility for lighting designs, allows many challenging designs, and improves energy-efficiency simultaneously.

  16. Get More from Your Lighting.

    ERIC Educational Resources Information Center

    Bachner, John Philip

    1999-01-01

    Explains how improved lighting can pay for installation of a new system or upgrading existing lighting in an educational facility. Examples explore the use of high-benefit lighting to enhance other activities and reduce crime and security patrolling costs. Also discussed is the upgrading of one school's sports arena lighting that produced…

  17. Short Course in Highway Lighting.

    ERIC Educational Resources Information Center

    Federal Highway Administration (DOT), Washington, DC.

    This course guide in highway lighting includes an overview of trends in highway lighting, illustrated information on three light sources for today's luminaires, a reference guide to lamp classification, specifications for highway lighting equipment, and instructions for calculating appropriate use. Maintenance notes on highway illumination and…

  18. Rice Rab11 is required for JA-mediated defense signaling

    SciTech Connect

    Hong, Min Ji; Lee, Yun mi; Son, Young Sim; Im, Chak Han; Yi, Young Byung; Rim, Yeong Gil; Bahk, Jeong Dong; Heo, Jae Bok

    2013-05-17

    Highlights: •OsRab11 interacts with OsOPR8. •OsOPR8 is localized in the cytosol and peroxisome. •OsRab11 enhances the NADPH consumption by OsOPR8. •Transgenic Arabidopsis overexpressing OsRab11 represents a pathogen-resistant phenotype. -- Abstract: Rab proteins play an essential role in regulating vesicular transport in eukaryotic cells. Previously, we characterized OsRab11, which in concert with OsGAP1 and OsGDI3 regulates vesicular trafficking from the trans-Golgi network (TGN) to the plasma membrane or vacuole. To further elucidate the physiological function of OsRab11 in plants, we performed yeast two-hybrid screens using OsRab11 as bait. OsOPR8 was isolated and shown to interact with OsRab11. A co-immunoprecipitation assay confirmed this interaction. The green fluorescent protein-OsOPR8 fusion product was targeted to the cytoplasm and peroxisomes of protoplasts from Arabidopsis thaliana. OsOPR8 exhibited NADPH-dependent reduction activity when 2-cyclohexen-1-one (CyHE) and 12-oxo-phytodienoic acid (OPDA) were supplied as possible substrates. Interestingly, NADPH oxidation by OsOPR8 was increased when wild-type OsRab11 or the constitutively active form of OsRab11 (Q78L) were included in the reaction mix, but not when the dominant negative form of OsRab11 (S28N) was included. OsRab11 was expressed broadly in plants and both OsRab11 and OsOPR8 were induced by jasmonic acid (JA) and elicitor treatments. Overexpressed OsRab11 transgenic plants showed resistance to pathogens through induced expression of JA-responsive genes. In conclusion, OsRab11 may be required for JA-mediated defense signaling by activating the reducing activity of OsOPR8.

  19. Volumetric Light-Field Excitation

    PubMed Central

    Schedl, David C.; Bimber, Oliver

    2016-01-01

    We explain how to concentrate light simultaneously at multiple selected volumetric positions by means of a 4D illumination light field. First, to select target objects, a 4D imaging light field is captured. A light field mask is then computed automatically for this selection to avoid illumination of the remaining areas. With one-photon illumination, simultaneous generation of complex volumetric light patterns becomes possible. As a full light-field can be captured and projected simultaneously at the desired exposure and excitation times, short readout and lighting durations are supported. PMID:27363565

  20. Green light in photomorphogenic development

    NASA Astrophysics Data System (ADS)

    Maruhnich, Stefanie Anne

    Light quality, quantity, and duration provide essential environmental cues that shape plant growth and development. Over the last century, researchers have worked to discover how plants sense, integrate, and respond to red, blue, and far-red light. Green light is often considered a “benign” wavelength with little to no effect in plant development. However, sparse experiments in the literature demonstrate that green effects are often counterintuitive to normal light responses and oppose red- and blue-light-induced responses. Green light effects on plant growth and development are described here through the use of custom, tunable LED, light-emitting diode, chambers. These light sources allow for specific light qualities and quantities to be administered. The effects of green wavebands were assessed when red and blue photomorphogenic systems were active to answer the question: Are the effects of an inhibitor (green light) more evident in the presence of inducers (red and blue light)? In seedlings, supplemental green light increased hypocotyl elongation opposite to classical inhibition of hypocotyl elongation associated with growth in light and induced by red and blue wavebands. Results indicate that added green light induced a reversion of light-grown phenotypes. In mature plants, supplemental green light induced phenotypes typical of the shade-avoidance syndrome, including elongated petioles, smaller leaf areas, and leaf hyponasty. These responses are typical of lower-light conditions or far-red enriched environments. Contrary to far-red-light-induced shade-avoidance, data indicate green delays flowering. In Arabidopsis and strawberry plants, anthocyanin levels also decreased when green light was added to red and blue light treatments, which is again opposite to normal light-induced phenotypes. Photoreceptor mutants were tested and indicate green light effects in early development are cryptochromedependent. However, green-light-induced shade-avoidance responses

  1. Lighting for Our Schools.

    ERIC Educational Resources Information Center

    Rankin, John C.

    In this speech, the author traces the history of lighting in schools, discusses the variables affecting the amount of illuminance needed, and provides a table of illuminances recommended for Ontario schools. Other factors that affect vision--glare, veiling reflection, color, and brightness balance--are outlined. Planners are admonished to…

  2. Playing with Light.

    ERIC Educational Resources Information Center

    Cavicchi, Elizabeth; Lucht, Petra; Hughes-McDonnell, Fiona

    2000-01-01

    Challenges the belief that high stakes tests are the keystone of students' educational attainment, describing a series of exploratory workshops, developed in reaction to this issue, in which teachers (as essential preparation for developing students' curiosity) deepened their understanding of the principles of physics by playing with light. Such…

  3. Cauldron of Light

    NASA Image and Video Library

    2008-05-29

    A seething cauldron of light appears to bubble and ooze around the remains of a giant star that astronomers have been watching tear itself apart for the last 300 years. Different observations taken over three years by NASA Spitzer Space Telescope.

  4. Lighting the Way

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2007-01-01

    In recent years, more education administrators and designers have embraced the potential benefits of daylighting. They have been persuaded that using natural light to illuminate facilities enables schools and universities to conserve energy and provide a learning environment in which students perform better. For daylighting advocates, the…

  5. Radioluminescent polymer lights

    SciTech Connect

    Jensen, G.A.; Nelson, D.A.; Molton, P.M.

    1990-09-01

    The preparation of radioluminescent light sources where the tritium is located on the aryl-ring in a polymer has been demonstrated with deuterium/tritium substitution. This report discusses tests, results, and future applications of radioluminescent polymers. 10 refs. (FI)

  6. Polarized Light: Three Demonstrations.

    ERIC Educational Resources Information Center

    Goehmann, Ruth; Welty, Scott

    1984-01-01

    Describes three demonstrations used in the Chicago Museum of Science and Industry polarized light show. The procedures employed are suitable for the classroom by using smaller polarizers and an overhead projector. Topic areas include properties of cellophane tape, nondisappearing arrows, and rope through a picket fence. (JN)

  7. Light Exotic Mesons

    NASA Astrophysics Data System (ADS)

    Eugenio, Paul

    2016-03-01

    tudies of meson spectra via strong decays provide insight regarding QCD at the confinement scale. These studies have led to phenomenological models for QCD such as the constituent quark model. However, QCD allows for a much richer spectrum of meson states which include extra states such as hybrids, exotics, multi-quarks, and glueballs. Within the past two decades a number of experiments have put forth tantalizing evidence for the existence of light quark exotic hybrid mesons in the mass range below 2 GeV . Recent Lattice QCD calculations of the light-quark meson spectrum indicate a constituent gluon-like excitation contributing an additional JPC =1+- and mass 1 - 1 . 5 GeV resulting in the lightest hybrid nonets with masses near 2 . 0 GeV . High statistical yields from recent experiments along with new advances in analysis techniques have shed a new light towards the understanding the latest experimental exotic candidates. Recent results from hadro-production and photo-production will be presented followed by an overview of ongoing and future efforts to search for light exotic mesons.

  8. Conceptualization of Light Refraction

    ERIC Educational Resources Information Center

    Sokolowski, Andrzej

    2013-01-01

    There have been a number of papers dealing quantitatively with light refraction. Yet the conceptualization of the phenomenon that sets the foundation for a more rigorous math analysis is minimized. The purpose of this paper is to fill that gap. (Contains 3 figures.)

  9. Lights and Larvae

    ERIC Educational Resources Information Center

    TItlow, Josh; Anderson, Heidi; Cooper, Robin

    2014-01-01

    Switching genes between organisms and controlling an animal's brain using lasers may seem like science fiction, but with advancements in a technique called optogenetics, such experiments are now common in neuroscience research. Optogenetics combines recombinant DNA technology with a controlled light source to help researchers address…

  10. Light-created chemiluminescence

    NASA Astrophysics Data System (ADS)

    Vasil'ev, Rostislav F.; Tsaplev, Yuri B.

    2006-11-01

    The results of studies of light-created chemiluminescence are described systematically. Conditions for the transformation of a dark chemical reaction into a chemiluminescence reaction are considered. Examples of photosensitised and photoinduced processes as well as of analytical applications are given.

  11. Bringing Light onto Shadows

    ERIC Educational Resources Information Center

    Barrow, Lloyd H.

    2007-01-01

    "What starts out long but gets shorter then longer each day?" Shadows! This student's clever riddle was an opportunity to investigate how the Sun's daily position in the sky influences shadow length. Thus began a mini-lesson which was created to help third-grade students understand that a shadow occurs when an opaque object blocks light (Shapiro…

  12. Circus of Light

    ERIC Educational Resources Information Center

    Matkins, Juanita Jo; McDonnough, Jacqueline

    2004-01-01

    This article describes the light-based science circus the authors developed and tested with a fifth-grade class at Blackwell Elementary School in Richmond, Virginia. A science circus is a set of activities done in any order that together illustrate complementary properties of a science topic. As in a traditional circus, several "performances"…

  13. Fluorescence and Light Scattering

    ERIC Educational Resources Information Center

    Clarke, Ronald J.; Oprysa, Anna

    2004-01-01

    The aim of the mentioned experiment is to aid students in developing tactics for distinguishing between signals originating from fluorescence and light scattering. Also, the experiment provides students with a deeper understanding of the physicochemical bases of each phenomenon and shows that the techniques are actually related.

  14. The Bright Lights

    ERIC Educational Resources Information Center

    Progressive Architecture, 1976

    1976-01-01

    High intensity discharge lighting sources share the compactness and beam controllability of incandescent sources, but are far more efficient and longer-lived. They share the efficiency and long life of fluorescent sources, but are compact and optically controllable, and are available in higher wattages. (Author/MLF)

  15. Light and Cool

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2010-01-01

    When the subject of buildings and daylighting arises, most people's thoughts will turn first to windows. To the uninitiated, it seems a simple formula: more windows, more daylight; fewer windows, less daylight. But designers know that effective use of daylighting in a building design involves more than just letting in light to otherwise darkened…

  16. Lighting up Savings.

    ERIC Educational Resources Information Center

    Ryerson, Charles

    1996-01-01

    Suggests group relamping in educational facilities as a more efficient method than spot replacement of failed lamps. It can reduce operating costs, improve lighting quality, and help with federal and state regulations compliance. The implementation of group relamping is discussed in terms of planning, energy savings, and environmental issues. (RE)

  17. Technology reviews: Lighting systems

    SciTech Connect

    Schuman, J.; Rubinstein, F.; Papamichael, K.; Beltran, L.; Lee, E.S.; Selkowitz, S.

    1992-09-01

    We present a representative review of existing, emerging, and future technology options in each of five hardware and systems areas in envelope and lighting technologies: lighting systems, glazing systems, shading systems, daylighting optical systems, and dynamic curtain wall systems. The term technology is used here to describe any design choice for energy efficiency, ranging from individual components to more complex systems to general design strategies. The purpose of this task is to characterize lighting system in the state of the art in envelope and lighting technologies in order to identify those with promise for advanced integrated systems, with an emphasis on California commercial buildings. For each technology category, the following activities have been attempted to the extent possible: Identify key performance characteristics and criteria for each technology. Determine the performance range of available technologies. Identify the most promising technologies and promising trends in technology advances. Examine market forces and market trends. Develop a continuously growing in-house database to be used throughout the project. A variety of information sources have been used in these technology characterizations, including miscellaneous periodicals, manufacturer catalogs and cut sheets, other research documents, and data from previous computer simulations. We include these different sources in order to best show the type and variety of data available, however publication here does not imply our guarantee of these data. Within each category, several broad classes are identified, and within each class we examine the generic individual technologies that fall into that class.

  18. Lights, Camera, Chemistry!

    ERIC Educational Resources Information Center

    Lamb, William G.

    1984-01-01

    Recommends using dramatic demonstrations on the energy in chemical systems as an audiovisual adjunct to lectures and laboratory sessions. Lists materials needed and provides procedures including safety tips for various experiments to produce chemical light, heat, and electricity; and concludes with hints for preparation/rehearsal. (JM)

  19. Fluorescence and Light Scattering

    ERIC Educational Resources Information Center

    Clarke, Ronald J.; Oprysa, Anna

    2004-01-01

    The aim of the mentioned experiment is to aid students in developing tactics for distinguishing between signals originating from fluorescence and light scattering. Also, the experiment provides students with a deeper understanding of the physicochemical bases of each phenomenon and shows that the techniques are actually related.

  20. Solid State Lighting

    SciTech Connect

    Hastbacka, Mildred; Dieckmann, John; Bouza, Antonio

    2013-03-30

    The article discusses solid state lighting technologies. This topic was covered in two previous ASHRAE Journal columns (2010). This article covers advancements in technologies and the associated efficacies. The life-cycle, energy savings and market potential of these technologies are addressed as well.

  1. Light's Disappearing Act.

    ERIC Educational Resources Information Center

    Murphy, Richard S.; Kwasnoski, John B.

    1985-01-01

    With an aquarium and a few tools, a simple apparatus to quantitatively illustrate absorption rates of light passing through fresh, salt, and other waters (such as distilled water) can be constructed. Students learn that extinction rates are different and that the intensity/depth relationship is exponential. (DH)

  2. Windows and lighting program

    SciTech Connect

    Not Available

    1990-06-01

    More than 30% of all energy use in buildings is attributable to two sources: windows and lighting. Together they account for annual consumer energy expenditures of more than $50 billion. Each affects not only energy use by other major building systems, but also comfort and productivity -- factors that influence building economics far more than does direct energy consumption alone. Windows play a unique role in the building envelope, physically separating the conditioned space from the world outside without sacrificing vital visual contact. Throughout the indoor environment, lighting systems facilitate a variety of tasks associated with a wide range of visual requirements while defining the luminous qualities of the indoor environment. Windows and lighting are thus essential components of any comprehensive building science program. Despite important achievements in reducing building energy consumption over the past decade, significant additional savings are still possible. These will come from two complementary strategies: (1) improve building designs so that they effectively apply existing technologies and extend the market penetration of these technologies; and (2) develop advanced technologies that increase the savings potential of each application. Both the Windows and Daylighting Group and the Lighting System Research Group have made substantial contributions in each of these areas, and continue to do so through the ongoing research summarized here. 23 refs., 16 figs.

  3. Lighting up Savings.

    ERIC Educational Resources Information Center

    Ryerson, Charles

    1996-01-01

    Suggests group relamping in educational facilities as a more efficient method than spot replacement of failed lamps. It can reduce operating costs, improve lighting quality, and help with federal and state regulations compliance. The implementation of group relamping is discussed in terms of planning, energy savings, and environmental issues. (RE)

  4. Photoacoustics with coherent light

    PubMed Central

    Bossy, Emmanuel; Gigan, Sylvain

    2016-01-01

    Since its introduction in the mid-nineties, photoacoustic imaging of biological tissue has been one of the fastest growing biomedical imaging modality, and its basic principles are now considered as well established. In particular, light propagation in photoacoustic imaging is generally considered from the perspective of transport theory. However, recent breakthroughs in optics have shown that coherent light propagating through optically scattering medium could be manipulated towards novel imaging approaches. In this article, we first provide an introduction to the relevant concepts in the field, and then review the recent works showing that it is possible to exploit the coherence of light in conjunction with photoacoustics. We illustrate how the photoacoustic effect can be used as a powerful feedback mechanism for optical wavefront shaping in complex media, and conversely show how the coherence of light can be exploited to enhance photoacoustic imaging, for instance in terms of spatial resolution or for designing minimally invasive endoscopic devices. Finally, we discuss the current challenges and perspectives down the road towards practical applications in the field of photoacoustic imaging. PMID:27069874

  5. Lighting for Our Schools.

    ERIC Educational Resources Information Center

    Rankin, John C.

    In this speech, the author traces the history of lighting in schools, discusses the variables affecting the amount of illuminance needed, and provides a table of illuminances recommended for Ontario schools. Other factors that affect vision--glare, veiling reflection, color, and brightness balance--are outlined. Planners are admonished to…

  6. Conceptualization of Light Refraction

    ERIC Educational Resources Information Center

    Sokolowski, Andrzej

    2013-01-01

    There have been a number of papers dealing quantitatively with light refraction. Yet the conceptualization of the phenomenon that sets the foundation for a more rigorous math analysis is minimized. The purpose of this paper is to fill that gap. (Contains 3 figures.)

  7. Light in the temples.

    NASA Astrophysics Data System (ADS)

    Krupp, E. C.

    Contents: 1. The dawn of archaeoastronomy. 2. Stalking Lockyer. 3. Solar connotations at Karnak. 4. Solar sanctuaries at Abu Simbel. 5. Another look at the Sun. 6. The great temple of Amun-Re at Karnak. 7. The solar sanctuary of Hatshepsut's mortuary temple at Deir el-Bahri. 8. The Sun temple of Neuserre' at Abu Ghurab. 9. Shedding light on the temples.

  8. Lights and Larvae

    ERIC Educational Resources Information Center

    TItlow, Josh; Anderson, Heidi; Cooper, Robin

    2014-01-01

    Switching genes between organisms and controlling an animal's brain using lasers may seem like science fiction, but with advancements in a technique called optogenetics, such experiments are now common in neuroscience research. Optogenetics combines recombinant DNA technology with a controlled light source to help researchers address…

  9. Bringing Light onto Shadows

    ERIC Educational Resources Information Center

    Barrow, Lloyd H.

    2007-01-01

    "What starts out long but gets shorter then longer each day?" Shadows! This student's clever riddle was an opportunity to investigate how the Sun's daily position in the sky influences shadow length. Thus began a mini-lesson which was created to help third-grade students understand that a shadow occurs when an opaque object blocks light (Shapiro…

  10. Light microscopy digital imaging.

    PubMed

    Joubert, James; Sharma, Deepak

    2011-10-01

    This unit presents an overview of digital imaging hardware used in light microscopy. CMOS, CCD, and EMCCDs are the primary sensors used. The strengths and weaknesses of each define the primary applications for these sensors. Sensor architecture and formats are also reviewed. Color camera design strategies and sensor window cleaning are also described in the unit.

  11. High Brightness OLED Lighting

    SciTech Connect

    Spindler, Jeffrey; Kondakova, Marina; Boroson, Michael; Hamer, John

    2016-05-25

    In this work we describe the technology developments behind our current and future generations of high brightness OLED lighting panels. We have developed white and amber OLEDs with excellent performance based on the stacking approach. Current products achieve 40-60 lm/W, while future developments focus on achieving 80 lm/W or higher.

  12. Lighting the Way

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2007-01-01

    In recent years, more education administrators and designers have embraced the potential benefits of daylighting. They have been persuaded that using natural light to illuminate facilities enables schools and universities to conserve energy and provide a learning environment in which students perform better. For daylighting advocates, the…

  13. Polarized Light: Three Demonstrations.

    ERIC Educational Resources Information Center

    Goehmann, Ruth; Welty, Scott

    1984-01-01

    Describes three demonstrations used in the Chicago Museum of Science and Industry polarized light show. The procedures employed are suitable for the classroom by using smaller polarizers and an overhead projector. Topic areas include properties of cellophane tape, nondisappearing arrows, and rope through a picket fence. (JN)

  14. Abundances of light elements.

    PubMed Central

    Pagel, B E

    1993-01-01

    Recent developments in the study of abundances of light elements and their relevance to cosmological nucleosynthesis are briefly reviewed. The simplest model, based on standard cosmology and particle physics and assuming homogeneous baryon density at the relevant times, continues to stand up well. PMID:11607388

  15. Light and Cool

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2010-01-01

    When the subject of buildings and daylighting arises, most people's thoughts will turn first to windows. To the uninitiated, it seems a simple formula: more windows, more daylight; fewer windows, less daylight. But designers know that effective use of daylighting in a building design involves more than just letting in light to otherwise darkened…

  16. Light water reactor program

    SciTech Connect

    Franks, S.M.

    1994-12-31

    The US Department of Energy`s Light Water Reactor Program is outlined. The scope of the program consists of: design certification of evolutionary plants; design, development, and design certification of simplified passive plants; first-of-a-kind engineering to achieve commercial standardization; plant lifetime improvement; and advanced reactor severe accident program. These program activities of the Office of Nuclear Energy are discussed.

  17. Visualization and Measurement of the Deflagration of Metal-Foil Bounded JA2

    DTIC Science & Technology

    2015-06-01

    ARL‐TR‐7322 ● JUNE 2015          US Army Research Laboratory      Visualization and  Measurement  of the  Deflagration of Metal‐Foil Bounded...Visualization and  Measurement  of the  Deflagration of Metal‐Foil Bounded JA2    John J Ritter and Anthony Canami  Weapons and Materials Research...

  18. NASA Lighting Research, Test, & Analysis

    NASA Technical Reports Server (NTRS)

    Clark, Toni

    2015-01-01

    The Habitability and Human Factors Branch, at Johnson Space Center, in Houston, TX, provides technical guidance for the development of spaceflight lighting requirements, verification of light system performance, analysis of integrated environmental lighting systems, and research of lighting-related human performance issues. The Habitability & Human Factors Lighting Team maintains two physical facilities that are integrated to provide support. The Lighting Environment Test Facility (LETF) provides a controlled darkroom environment for physical verification of lighting systems with photometric and spetrographic measurement systems. The Graphics Research & Analysis Facility (GRAF) maintains the capability for computer-based analysis of operational lighting environments. The combined capabilities of the Lighting Team at Johnson Space Center have been used for a wide range of lighting-related issues.

  19. Radioluminescent lighting technology

    NASA Astrophysics Data System (ADS)

    The glow-in-the-dark stereotype that characterizes the popular image of nuclear materials is not accidental. When the French scientist, Henri Becquerel, first discovered radioactivity in 1896, he was interested in luminescence. Radioluminescence, the production of light from a mixture of energetic and passive materials, is probably the oldest practical application of the unstable nucleus. Tritium based radioluminescent lighting, in spite of the biologically favorable character of the gaseous tritium isotope, was included in the general tightening of environmental and safety regulations. Tritium light manufacturers would have to meet two fundamental conditions: (1) The benefit clearly outweighed the risk, to the extent that even the perceived risk of a skeptical public would be overcome; and (2) The need was significant enough that the customer/user would be willing and able to afford the cost of regulation that was imposed both in the manufacture, use, and eventual disposal of nuclear materials. In 1981, researchers at Oak Ridge National Laboratory were investigating larger radioluminescent applications using byproduct nuclear material such as krypton-85, as well as tritium. By 1982, it appeared that large source, (100 Curies or more) tritium gas tube, lights might be useful for marking runways and drop zones for military operations and perhaps even special civilian aviation applications. The successful development of this idea depended on making the light bright enough and demonstrating that large gas tube sources could be used and maintained safely in the environment. The basic program goals were achieved. This is a detailed report of what they have learned, proven, and discovered.

  20. A light sneutrino rescues the light stop

    NASA Astrophysics Data System (ADS)

    Chala, M.; Delgado, A.; Nardini, G.; Quirós, M.

    2017-04-01

    Stop searches in supersymmetric frameworks with R-parity conservation usually assume the lightest neutralino to be the lightest supersymmetric particle. In this paper we consider an alternative scenario in which the left-handed tau sneutrino is lighter than neutralinos and stable at collider scales, but possibly unstable at cosmological scales. Moreover the (mostly right-handed) stop \\overset{˜ }{t} is lighter than all electroweakinos, and heavier than the scalars of the third generation lepton doublet, whose charged component, \\overset{˜ }{τ } , is heavier than the neutral one, \\overset{˜ }{ν } . The remaining supersymmetric particles are decoupled from the stop phenomenology. In most of the parameter space, the relevant stop decays are only into t\\overset{˜ }{τ}τ , t\\overset{˜ }{ν}ν and b\\overset{˜ }{ν}τ via off-shell electroweakinos. We constrain the branching ratios of these decays by recasting the most sensitive stop searches. Due to the "double invisible" kinematics of the \\overset{˜ }{t}\\to t\\overset{˜ }{ν}ν process, and the low efficiency in tagging the t\\overset{˜ }{τ}τ decay products, light stops are generically allowed. In the minimal supersymmetric standard model with ˜ 100 GeV sneutrinos, stops with masses as small as ˜ 350 GeV turn out to be allowed at 95% CL.

  1. Analysis of light regime in continuous light distributions in photobioreactors.

    PubMed

    Brindley, Celeste; Fernández, F G Acién; Fernández-Sevilla, J M

    2011-02-01

    Maximum photobioreactor (PBR) efficiency is a must in applications such as the obtention of microalgae-derived fuels. Improving PBR performance requires a better understanding of the "light regime", the varying irradiance that microalgal cells moving in a dense culture are exposed to. We propose a definition of light regime that can be used consistently to describe the continuously varying light patterns in PBRs as well as in light/dark cycles. Equivalent continuous and light/dark regimes have been experimentally compared and the results show that continuous variations are not well represented by light/dark cycles, as had been widely accepted. It has been shown that a correct light regime allows obtaining photosynthetic rates higher than the corresponding to continuous light, the so-called "flashing light effect" and that this is possible in commercial PBRs. A correct PBR operation could result in photosynthetic efficiency close to the optimum eight quanta per O(2).

  2. MAPK-dependent JA and SA signalling in Nicotiana attenuata affects plant growth and fitness during competition with conspecifics.

    PubMed

    Meldau, Stefan; Ullman-Zeunert, Lynn; Govind, Geetha; Bartram, Stefan; Baldwin, Ian T

    2012-11-13

    Induced defense responses to herbivores are generally believed to have evolved as cost-saving strategies that defer the fitness costs of defense metabolism until these defenses are needed. The fitness costs of jasmonate (JA)-mediated defenses have been well documented. Those of the early signaling units mediating induced resistance to herbivores have yet to be examined. Early signaling components that mediate herbivore-induced defense responses in Nicotiana attenuata, have been well characterized and here we examine their growth and fitness costs during competition with conspecifics. Two mitogen-activated protein kinases (MAPKs), salicylic acid (SA)-induced protein kinase (SIPK) and wound-induced protein kinase (WIPK) are rapidly activated after perception of herbivory and both kinases regulate herbivory-induced JA levels and JA-mediated defense metabolite accumulations. Since JA-induced defenses result in resource-based trade-offs that compromise plant productivity, we evaluated if silencing SIPK (irSIPK) and WIPK (irWIPK) benefits the growth and fitness of plants competiting with wild type (WT) plants, as has been shown for plants silenced in JA-signaling by the reduction of Lipoxygenase 3 (LOX3) levels. As expected, irWIPK and LOX3-silenced plants out-performed their competing WT plants. Surprisingly, irSIPK plants, which have the largest reductions in JA signaling, did not. Phytohormone profiling of leaves revealed that irSIPK plants accumulated higher levels of SA compared to WT. To test the hypothesis that these high levels of SA, and their presumed associated fitness costs of pathogen associated defenses in irSIPK plants had nullified the JA-deficiency-mediated growth benefits in these plants, we genetically reduced SA levels in irSIPK plants. Reducing SA levels partially recovered the biomass and fitness deficits of irSIPK plants. We also evaluated whether the increased fitness of plants with reduced SA or JA levels resulted from increased nitrogen or CO

  3. MAPK-dependent JA and SA signalling in Nicotiana attenuata affects plant growth and fitness during competition with conspecifics

    PubMed Central

    2012-01-01

    Background Induced defense responses to herbivores are generally believed to have evolved as cost-saving strategies that defer the fitness costs of defense metabolism until these defenses are needed. The fitness costs of jasmonate (JA)-mediated defenses have been well documented. Those of the early signaling units mediating induced resistance to herbivores have yet to be examined. Early signaling components that mediate herbivore-induced defense responses in Nicotiana attenuata, have been well characterized and here we examine their growth and fitness costs during competition with conspecifics. Two mitogen-activated protein kinases (MAPKs), salicylic acid (SA)-induced protein kinase (SIPK) and wound-induced protein kinase (WIPK) are rapidly activated after perception of herbivory and both kinases regulate herbivory-induced JA levels and JA-mediated defense metabolite accumulations. Since JA-induced defenses result in resource-based trade-offs that compromise plant productivity, we evaluated if silencing SIPK (irSIPK) and WIPK (irWIPK) benefits the growth and fitness of plants competiting with wild type (WT) plants, as has been shown for plants silenced in JA-signaling by the reduction of Lipoxygenase 3 (LOX3) levels. Results As expected, irWIPK and LOX3-silenced plants out-performed their competing WT plants. Surprisingly, irSIPK plants, which have the largest reductions in JA signaling, did not. Phytohormone profiling of leaves revealed that irSIPK plants accumulated higher levels of SA compared to WT. To test the hypothesis that these high levels of SA, and their presumed associated fitness costs of pathogen associated defenses in irSIPK plants had nullified the JA-deficiency-mediated growth benefits in these plants, we genetically reduced SA levels in irSIPK plants. Reducing SA levels partially recovered the biomass and fitness deficits of irSIPK plants. We also evaluated whether the increased fitness of plants with reduced SA or JA levels resulted from

  4. Carbon catabolite repression-independent and pH-dependent production of indoles by Rubrivivax benzoatilyticus JA2.

    PubMed

    Mujahid, Md; Sasikala, Ch; Ramana, Ch V

    2013-10-01

    Rubrivivax benzoatilyticus JA2 produces indole derivatives (indoles) from aniline, anthranilate or L-tryptophan. Glucose repressed indole production in R. benzoatilyticus JA2, while malate had no effect. Growth of R. benzoatilyticus JA2 on glucose resulted in decrease in culture pH (6.4) compared with malate (8.4). Growth of R. benzoatilyticus JA2 on sugar carbon sources decreased culture pH (6.4-6.6) and indole production. Further, culture pH of 6.4 repressed the indole production, and pH 8.4 promoted the production irrespective of carbon sources used for growth. Moreover, correlation between indole production and culture pH was observed, where acidic pH inhibited indole production, while alkaline pH promoted the production, suggesting the role of pH in indole production. Tryptophan-catabolizing enzyme activities are significantly high in malate-grown cultures (pH 8.4) compared with that of the glucose (pH 6.4)-grown cultures and corroborated well with indole production, indicating their role in indole production. These results confirm that indole production in R. benzoatilyticus JA2 is pH dependent rather than carbon catabolite repression.

  5. OsJAR1 is required for JA-regulated floret opening and anther dehiscence in rice.

    PubMed

    Xiao, Yuguo; Chen, Yi; Charnikhova, Tatsiana; Mulder, Patrick P J; Heijmans, Jeroen; Hoogenboom, Angela; Agalou, Adamantia; Michel, Corinne; Morel, Jean-Benoit; Dreni, Ludovico; Kater, Martin M; Bouwmeester, Harro; Wang, Mei; Zhu, Zhen; Ouwerkerk, Pieter B F

    2014-09-01

    Jasmonates are important phytohormones regulating reproductive development. We used two recessive rice Tos17 alleles of OsJAR1, osjar1-2 and osjar1-3, to study the biological function of jasmonates in rice anthesis. The florets of both osjar1 alleles stayed open during anthesis because the lodicules, which control flower opening in rice, were not withering on time. Furthermore, dehiscence of the anthers filled with viable pollen, was impaired, resulting in lower fertility. In situ hybridization and promoter GUS transgenic analysis confirmed OsJAR1 expression in these floral tissues. Flower opening induced by exogenous applied methyl jasmonate was impaired in osjar1 plants and was restored in a complementation experiment with transgenics expressing a wild type copy of OsJAR1 controlled by a rice actin promoter. Biochemical analysis showed that OsJAR1 encoded an enzyme conjugating jasmonic acid (JA) to at least Ile, Leu, Met, Phe, Trp and Val and both osjar1 alleles had substantial reduction in content of JA-Ile, JA-Leu and JA-Val in florets. We conclude that OsJAR1 is a JA-amino acid synthetase that is required for optimal flower opening and closing and anther dehiscence in rice.

  6. The tomato res mutant which accumulates JA in roots in non-stressed conditions restores cell structure alterations under salinity.

    PubMed

    Garcia-Abellan, José O; Fernandez-Garcia, Nieves; Lopez-Berenguer, Carmen; Egea, Isabel; Flores, Francisco B; Angosto, Trinidad; Capel, Juan; Lozano, Rafael; Pineda, Benito; Moreno, Vicente; Olmos, Enrique; Bolarin, Maria C

    2015-11-01

    Jasmonic acid (JA) regulates a wide spectrum of plant biological processes, from plant development to stress defense responses. The role of JA in plant response to salt stress is scarcely known, and even less known is the specific response in root, the main plant organ responsible for ionic uptake and transport to the shoot. Here we report the characterization of the first tomato (Solanum lycopersicum) mutant, named res (restored cell structure by salinity), that accumulates JA in roots prior to exposure to stress. The res tomato mutant presented remarkable growth inhibition and displayed important morphological alterations and cellular disorganization in roots and leaves under control conditions, while these alterations disappeared when the res mutant plants were grown under salt stress. Reciprocal grafting between res and wild type (WT) (tomato cv. Moneymaker) indicated that the main organ responsible for the development of alterations was the root. The JA-signaling pathway is activated in res roots prior to stress, with transcripts levels being even higher in control condition than in salinity. Future studies on this mutant will provide significant advances in the knowledge of JA role in root in salt-stress tolerance response, as well as in the energy trade-off between plant growth and response to stress.

  7. The International Year of Light and Light-based Technologies

    NASA Astrophysics Data System (ADS)

    Pendrill, Ann-Marie

    2015-05-01

    I report on the opening ceremony of the International Year of Light and Light-based Technologies 2015 (IYL2015), which took place at the UNESCO headquarters in Paris, France, on 19-20 January 2015. Over the two days, more than 1000 participants from all over the world learned more about the fundamental properties of light and advanced photonics applications, the history of optics and its applications through the centuries, light poverty and light pollution, and light for everyday life, health and research.

  8. Experimental demonstration of light sensor-based visible light communications using time shift light intensity modulation

    NASA Astrophysics Data System (ADS)

    Kim, Yong-hyeon; Chung, Yeon-ho

    2016-09-01

    An experimental light sensor-based indoor visible light communication (VLC) is presented. Light-emitting diodes (LEDs) primarily used for illumination are employed to transmit wireless optical data over a short distance, while a smartphone's light sensor is used to receive the data. The light sensor in a smartphone is originally installed to function as a power saving method by adjusting the brightness of the smartphone screen. We propose an efficient and easy-to-use short range VLC based on this light sensor. To compensate for the inherent low sampling rate of the light sensor and also to avoid LED (transmitter) flickering, we propose time shift light intensity modulation. To verify the proposed light sensor VLC, experiments were conducted. The results demonstrate that the data can reliably be transmitted over the VLC link between the LEDs and the smartphone light sensor.

  9. Draft genome sequence of Rhodomicrobium udaipurense JA643T with special reference to hopanoid biosynthesis.

    PubMed

    Tushar, L; Sasikala, Ch; Ramana, Ch V

    2014-12-01

    Hopanoids are present in vast amounts as integral components of bacteria and plants with their primary function to strengthen rigidity of the plasma membrane. To establish their roles more precisely, we conducted sequencing of the whole genome of Rhodomicrobium udaipurense JA643(T) isolated from a fresh water stream of Udaipur in Himachal Pradesh, India, by using the Illumina HiSeq pair end chemistry of 2 × 100 bp platform. Determined genome showed a high degree of similarity to the genome of R. vannielii ATCC17100(T) and the 13.7 million reads generated a sequence of 3,649,277 bp possessing 3,611 putative genes. The genomic data were subsequently investigated with respect to genes involved in various features. The machinery required for the degradation of aromatic compounds and resistance to solvents as well as all that required for photosynthesis are present in this organism. Also, through extensive functional annotation, 18 genes involved in the biosynthesis of hopanoids are predicted, namely those responsible for the synthesis of diploptene, diplopterol, adenosylhopane, ribosylhopane, aminobacteriohopanetriol, glycosyl group containing hopanoids and unsaturated hopanoids. The hopanoid biosynthetic pathway was then inferred based on the genes identified and through experimental validation of individual hopanoid molecules. The genome data of R. udaipurense JA643(T) will be useful in understanding the functional features of hopanoids in this bacterium.

  10. Early dust formation and a massive progenitor for SN 2011ja?

    NASA Astrophysics Data System (ADS)

    Andrews, J. E.; Krafton, Kelsie M.; Clayton, Geoffrey C.; Montiel, E.; Wesson, R.; Sugerman, Ben E. K.; Barlow, M. J.; Matsuura, M.; Drass, H.

    2016-04-01

    SN 2011ja was a bright (I = -18.3) Type II supernova occurring in the nearby edge on spiral galaxy NGC 4945. Flat-topped and multipeaked H α and H β spectral emission lines appear between 64 and 84 d post-explosion, indicating interaction with a disc-like circumstellar medium inclined ˜45° from edge-on. After day 84, an increase in the H- and K-band flux along with heavy attenuation of the red wing of the emission lines are strong indications of early dust formation, likely located in the cool dense shell created between the forward shock of the SN ejecta and the reverse shock created as the ejecta plows into the existing circumstellar material. Radiative transfer modelling reveals both ≈1 × 10-5 M⊙ of pre-existing dust located ˜1016.7 cm away and up to ≈6 × 10-4 M⊙ of newly formed dust. Spectral observations after 1.5 yr reveal the possibility that the fading SN is located within a young (3-6 Myr) massive stellar cluster, which when combined with tentative 56Ni mass estimates of 0.2 M⊙ may indicate a massive (≥25 M⊙) progenitor for SN 2011ja.

  11. Kinetics and regulation of lactose transport and metabolism in Kluyveromyces lactis JA6.

    PubMed

    Santos, A M; Silveira, W B; Fietto, L G; Brandão, R L; Castro, I M

    2014-07-01

    Kluyveromyces lactis strains are able to assimilate lactose. They have been used industrially to eliminate this sugar from cheese whey and in other industrial products. In this study, we investigated specific features and the kinetic parameters of the lactose transport system in K. lactis JA6. In lactose grown cells, lactose was transported by a system transport with a half-saturation constant (K s) of 1.49 ± 0.38 mM and a maximum velocity (V max) of 0.96 ± 0.12 mmol. (g dry weight)(-1) h(-1) for lactose. The transport system was constitutive and energy-dependent. Results obtained by different approaches showed that the lactose transport system was regulated by glucose at the transcriptional level and by glucose and other sugars at a post-translational level. In K. lactis JA6, galactose metabolization was under glucose control. These findings indicated that the regulation of lactose-galactose regulon in K. lactis was similar to the regulation of galactose regulon in Saccharomyces cerevisiae.

  12. Semi-imaging light pipe for collecting weakly scattered light

    NASA Astrophysics Data System (ADS)

    Hopkins, George W.; Simons, Tad D.

    1998-09-01

    A simple reflective light pipe, formed from a cylindrical tube with an external reflective coating and a small central aperture, can be a highly efficient optical element for collecting light from molecular scattering processes along the path of a laser beam. When the laser beam is co-linear with the axis of the light pipe, scattered light from any location along the interaction region (near the pipe axis) re-images repeatedly to another location along the axis of the pipe. This semi-imaging property of the light pipe permits a large fraction of the total scattered light to re- image along the entire length of the interaction region. If one observes through the small central aperture, scattered light from the single segment of the laser beam in view appears to come from all the locations along the interaction length, as well as from the single segment. In this manner, one can have the advantage of collecting scattered light from a small segment (and thus onto a small detector), while observing an effective interaction length that is many times longer than the segment. Measurements from practical light pipes confirm effective gains of about 10X with light pipes a few centimeters long (Effective gain is defined as the ratio of light collected with the light pipe divided by the light collected from a direct image of the beam using the collection optics).

  13. Fundamentals of Polarized Light

    NASA Technical Reports Server (NTRS)

    Mishchenko, Michael

    2003-01-01

    The analytical and numerical basis for describing scattering properties of media composed of small discrete particles is formed by the classical electromagnetic theory. Although there are several excellent textbooks outlining the fundamentals of this theory, it is convenient for our purposes to begin with a summary of those concepts and equations that are central to the subject of this book and will be used extensively in the following chapters. We start by formulating Maxwell's equations and constitutive relations for time- harmonic macroscopic electromagnetic fields and derive the simplest plane-wave solution that underlies the basic optical idea of a monochromatic parallel beam of light. This solution naturally leads to the introduction of such fundamental quantities as the refractive index and the Stokes parameters. Finally, we define the concept of a quasi-monochromatic beam of light and discuss its implications.

  14. Polarized Light from Jupiter

    NASA Technical Reports Server (NTRS)

    2001-01-01

    These images taken through the wide angle camera near closest approach in the deep near-infrared methane band, combined with filters which sense electromagnetic radiation of orthogonal polarization, show that the light from the poles is polarized. That is, the poles appear bright in one image, and dark in the other. Polarized light is most readily scattered by aerosols. These images indicate that the aerosol particles at Jupiter's poles are small and likely consist of aggregates of even smaller particles, whereas the particles at the equator and covering the Great Red Spot are larger. Images like these will allow scientists to ascertain the distribution, size and shape of aerosols, and consequently, the distribution of heat, in Jupiter's atmosphere.

  15. Light amplification using semiconductors

    SciTech Connect

    Dupuis, R.D.

    1987-06-01

    During the summer of 1953, John von Neumann discussed his ideas concerning light amplification using semiconductors with Edward Teller. In September of that year, von Neumann sent a manuscript containing his ideas and calculations on this subject to Teller for his comments. To the best of our knowledge, von Neumann did not take time to work further on these ideas, and the manuscript remained unpublished. These previously unpublished writings of John von Neumann on the subject of light amplification in semiconductors are printed as a service to the laser community. While von Neumann's original manuscript and his letter to Teller are available to anyone who visits the Library of Congress, it is much more convenient to have this paper appear in an archival journal.

  16. Parametric light generation.

    PubMed

    Ebrahimzadeh, M

    2003-12-15

    Since its invention more than 40 years ago, the laser has become an indispensable optical tool, capable of transforming light from its naturally incoherent state to a highly coherent state in space and time. Yet, due to fundamental limitations, operation of the laser remains confined to restricted spectral and temporal regions. Nonlinear optics can overcome this limitation by allowing access to new spectral and temporal regimes through the exploitation of suitable dielectric materials in combination with the laser. In particular, optical parametric oscillators are versatile coherent light sources with unique flexibility that can provide optical radiation across an entire spectral range from the ultraviolet to the far-infrared and over all temporal scales from continuous wave to the ultrafast femtosecond domain.

  17. Light Localisation and Lasing

    NASA Astrophysics Data System (ADS)

    Ghulinyan, Mher; Pavesi, Lorenzo

    2014-12-01

    List of contributors; Preface; 1. Light propagation and emission in complex photonic media W. L. Vos, A. Lagendijk and A. P. Mosk; 2. Transport of localized waves via modes and channels A. Genack and Z. Shi; 3. Modes structure and interaction in random lasers M. Leonetti and C. Lopez; 4. Ordered and disordered light transport in couple microring resonators S. Mookherjea; 5. One-dimensional photonic quasicrystals M. Ghulinyan; 6. 2D pseudo-random and deterministic aperiodic lasers H. Cao, H. Noh and L. Dal Negro; 7. 3D photonic quasicrystal and deterministic aperiodic structures A. Ledermann, M. Renner and G. von Freymann; 8. Cavity quantum electrodynamics with three-dimensional photonic bandgap crystals W. L. Vos and L. A. Woldering; References; Index.

  18. Braiding light quanta

    NASA Astrophysics Data System (ADS)

    Iadecola, Thomas; Schuster, Thomas; Chamon, Claudio

    The possibility that anyons -- quantum particles other than fermions or bosons -- can emerge in condensed matter systems has motivated generations of physicists. In addition to being of fundamental scientific importance, so-called non-Abelian anyons are particularly sought-after for potential applications to quantum computing. However, experimental evidence of anyons in electronic systems remains inconclusive. We propose to demonstrate non-Abelian braiding by injecting coherent states of light into ``topological guided modes'' in specially-fabricated photonic waveguide arrays. These modes are photonic analogues of topological zero modes in electronic systems. Light traveling inside spatially well-separated topological guided modes can be braided, leading to the accumulation of non-Abelian phases. We propose an optical interference experiment to probe this non-Abelian braiding directly. T.I. is supported by a National Science Foundation Graduate Research Fellowship under Grant No. DGE-1247312.

  19. Fusion pumped light source

    DOEpatents

    Pappas, Daniel S.

    1989-01-01

    Apparatus is provided for generating energy in the form of light radiation. A fusion reactor is provided for generating a long, or continuous, pulse of high-energy neutrons. The neutron flux is coupled directly with the lasing medium. The lasing medium includes a first component selected from Group O of the periodic table of the elements and having a high inelastic scattering cross section. Gamma radiation from the inelastic scattering reactions interacts with the first component to excite the first component, which decays by photon emission at a first output wavelength. The first output wavelength may be shifted to a second output wavelength using a second liquid component responsive to the first output wavelength. The light outputs may be converted to a coherent laser output by incorporating conventional optics adjacent the laser medium.

  20. Light from cosmic strings

    SciTech Connect

    Steer, Daniele A.; Vachaspati, Tanmay

    2011-02-15

    The time-dependent metric of a cosmic string leads to an effective interaction between the string and photons--the ''gravitational Aharonov-Bohm'' effect--and causes cosmic strings to emit light. We evaluate the radiation of pairs of photons from cosmic strings and find that the emission from cusps, kinks and kink-kink collisions occurs with a flat spectrum at all frequencies up to the string scale. Further, cusps emit a beam of photons, kinks emit along a curve, and the emission at a kink-kink collision is in all directions. The emission of light from cosmic strings could provide an important new observational signature of cosmic strings that is within reach of current experiments for a range of string tensions.

  1. OLEDS FOR GENERAL LIGHTING

    SciTech Connect

    Anil Duggal; Don Foust; Chris Heller; Bill Nealon; Larry Turner; Joe Shiang; Nick Baynes; Tim Butler; Nalin Patel

    2004-02-29

    The goal of this program was to reduce the long term technical risks that were keeping the lighting industry from embracing and developing organic light-emitting diode (OLED) technology for general illumination. The specific goal was to develop OLEDs for lighting to the point where it was possible to demonstrate a large area white light panel with brightness and light quality comparable to a fluorescence source and with an efficacy comparable to that of an incandescent source. it was recognized that achieving this would require significant advances in three area: (1) the improvement of white light quality for illumination, (2) the improvement of OLED energy efficiency at high brightness, and (3) the development of cost-effective large area fabrication techniques. The program was organized such that, each year, a ''deliverable'' device would be fabricated which demonstrated progress in one or more of the three critical research areas. In the first year (2001), effort concentrated on developing an OLED capable of generating high illumination-quality white light. Ultimately, a down-conversion method where a blue OLED was coupled with various down-conversion layers was chosen. Various color and scattering models were developed to aid in material development and device optimization. The first year utilized this approach to deliver a 1 inch x 1 inch OLED with higher illumination-quality than available fluorescent sources. A picture of this device is shown and performance metrics are listed. To their knowledge, this was the first demonstration of true illumination-quality light from an OLED. During the second year, effort concentrated on developing a scalable approach to large area devices. A novel device architecture consisting of dividing the device area into smaller elements that are monolithically connected in series was developed. In the course of this development, it was realized that, in addition to being scalable, this approach made the device tolerant to the most

  2. Visualizing stray light

    NASA Astrophysics Data System (ADS)

    Barron, Don R.

    1996-08-01

    Stray light in optical systems is usually assessed by techniques which are essentially similar to those used in the design synthesis of the system. In general however the dimensionality of the actual build of the system is far higher than that of the design and the traditional 'ray tracing' assessment techniques can become unmanageable. Modern computer graphics software developed for CAD and the entertainment industry has been applied to this problem at Pilkington Optronics as part of the process of integrated optomechanical design. This paper describes the relevant features of the new software packages as applied to the analysis of stray light and presents some results from particular systems. A useful feature of the technique is the use of animation to reduce the dimensionality; these examples cannot be presented here in written form but some simplified examples are available on request on 3.5 inch diskette format.

  3. EDITORIAL: LED light sources (light for the future) LED light sources (light for the future)

    NASA Astrophysics Data System (ADS)

    Grandjean, N.

    2010-09-01

    Generating white light from electricity with maximum efficacy has been a long quest since the first incandescent lamp was invented by Edison at the end of the 19th century. Nowadays, semiconductors are making reality the holy grail of converting electrons into photons with 100% efficiency and with colours that can be mixed for white light illumination. The revolution in solid-state lighting (SSL) dates to 1994 when Nakamura reported the first high-brightness blue LED based on GaN semiconductors. Then, white light was produced by simply combining a blue dye with a yellow phosphor. After more than a decade of intensive research the performance of white LEDs is quite impressive, beating by far the luminous efficacy of compact fluorescent lamps. We are likely close to replacing our current lighting devices by SSL lamps. However, there are still technological and fabrication cost issues that could delay large market penetration of white LEDs. Interestingly, SSL may create novel ways of using light that could potentially limit electricity saving. Whatever the impact of SSL, it will be significant on our daily life. The purpose of this special cluster issue is to produce a snapshot of the current situation of SSL from different viewing angles. In an introductory paper, Tsao and co-workers from Sandia National Laboratories, present an energy-economics perspective of SSL considering societal changes and SSL technology evolution. In a second article, Narukawa et al working at Nichia Corporation—the pioneer and still the leading company in SSL—describe the state of the art of current research products. They demonstrate record performance with white LEDs exhibiting luminous efficacy of 183 lm W-1 at high-current injection. Then, a series of topical papers discuss in detail various aspects of the physics and technology of white LEDs Carrier localization in InGaN quantum wells has been considered the key to white LEDs' success despite the huge density of defects. A

  4. Light cone matrix product

    SciTech Connect

    Hastings, Matthew B

    2009-01-01

    We show how to combine the light-cone and matrix product algorithms to simulate quantum systems far from equilibrium for long times. For the case of the XXZ spin chain at {Delta} = 0.5, we simulate to a time of {approx} 22.5. While part of the long simulation time is due to the use of the light-cone method, we also describe a modification of the infinite time-evolving bond decimation algorithm with improved numerical stability, and we describe how to incorporate symmetry into this algorithm. While statistical sampling error means that we are not yet able to make a definite statement, the behavior of the simulation at long times indicates the appearance of either 'revivals' in the order parameter as predicted by Hastings and Levitov (e-print arXiv:0806.4283) or of a distinct shoulder in the decay of the order parameter.

  5. [LED lights in dermatology].

    PubMed

    Noé, C; Pelletier-Aouizerate, M; Cartier, H

    2017-04-01

    The use in dermatology of light-emitting diodes (LEDs) continues to be surrounded by controversy. This is due mainly to poor knowledge of the physicochemical phases of a wide range of devices that are difficult to compare to one another, and also to divergences between irrefutable published evidence either at the level of in vitro studies or at the cellular level, and discordant clinical results in a variety of different indications: rejuvenation, acne, wound healing, leg ulcers, and cutaneous inflammatory or autoimmune processes. Therapeutic LEDs can emit wavelengths ranging from the ultraviolet, through visible light, to the near infrared (247-1300 nm), but only certain bands have so far demonstrated any real value. We feel certain that if this article remains factual, then readers will have a different, or at least more nuanced, opinion concerning the use of such LED devices in dermatology.

  6. Mapping nanoscale light fields

    NASA Astrophysics Data System (ADS)

    Rotenberg, N.; Kuipers, L.

    2014-12-01

    The control of light fields on subwavelength scales in nanophotonic structures has become ubiquitous, driven by both curiosity and a multitude of applications in fields ranging from biosensing to quantum optics. Mapping these fields in detail is crucial, as theoretical modelling is far from trivial and highly dependent on nanoscale geometry. Recent developments of nanoscale field mapping, particularly with near-field microscopy, have not only led to a vastly increased resolution, but have also resulted in increased functionality. The phase and amplitude of different vector components of both the electric and magnetic fields are now accessible, as is the ultrafast temporal or spectral evolution of propagating pulses in nanostructures. In this Review we assess the current state-of-the-art of subwavelength light mapping, highlighting the new science and nanostructures that have subsequently become accessible.

  7. Dichroic ultraviolet light filters

    NASA Astrophysics Data System (ADS)

    Kocher, Christoph; Weder, Christoph; Smith, Paul

    2003-10-01

    With the intention to produce dichroic filters for use in photoluminescent systems that rely on polarized UV light, we synthesized a number of linear, dichroic dyes, which absorb mainly in the near-UV range of the electromagnetic spectrum. These dyes were designed for compatibility with common thermoplastic polymers such as linear low-density poly(ethylene), poly(ethylene terephthalate), and polyamide-12. Films of these host polymers that consisted of 0.2% by weight of various dichroic UV dyes were produced by common melt-processing schemes. Uniaxial drawing of these films yielded highly dichroic UV filters with dichroic ratios in absorption that in some cases exceeded 100. The fact that these free-standing films display little or no coloration and are environmentally stable makes them useful for various applications that involve generation of polarized UV light.

  8. Scattering Of Light Nuclei

    SciTech Connect

    Quaglioni, S; Navratil, P; Roth, R

    2009-12-15

    The exact treatment of nuclei starting from the constituent nucleons and the fundamental interactions among them has been a long-standing goal in nuclear physics. Above all nuclear scattering and reactions, which require the solution of the many-body quantum-mechanical problem in the continuum, represent an extraordinary theoretical as well as computational challenge for ab initio approaches.We present a new ab initio many-body approach which derives from the combination of the ab initio no-core shell model with the resonating-group method [4]. By complementing a microscopic cluster technique with the use of realistic interactions, and a microscopic and consistent description of the nucleon clusters, this approach is capable of describing simultaneously both bound and scattering states in light nuclei. We will discuss applications to neutron and proton scattering on sand light p-shell nuclei using realistic nucleon-nucleon potentials, and outline the progress toward the treatment of more complex reactions.

  9. Sun light European Project

    NASA Astrophysics Data System (ADS)

    Soubielle, Marie-Laure

    2015-04-01

    2015 has been declared the year of light. Sunlight plays a major role in the world. From the sunbeams that heat our planet and feed our plants to the optical analysis of the sun or the modern use of sun particles in technologies, sunlight is everywhere and it is vital. This project aims to understand better the light of the Sun in a variety of fields. The experiments are carried out by students aged 15 to 20 in order to share their discoveries with Italian students from primary and secondary schools. The experiments will also be presented to a group of Danish students visiting our school in January. All experiments are carried out in English and involve teams of teachers. This project is 3 folds: part 1: Biological project = what are the mechanisms of photosynthesis? part 2: Optical project= what are the components of sunlight and how to use it? part 3: Technical project= how to use the energy of sunlight for modern devices? Photosynthesis project Biology and English Context:Photosynthesis is a process used by plants and other organisms to convert light energy, normally from the Sun, into chemical energy that can later fuel the organisms' activities. This chemical energy is stored in molecules which are synthesized from carbon dioxide and water. In most cases, oxygen is released as a waste product. Most plants perform photosynthesis. Photosynthesis maintains atmospheric oxygen levels and supplies all of the organic compounds and most of the energy necessary for life on Earth. Outcome: Our project consists in understanding the various steps of photosynthesis. Students will shoot a DVD of the experiments presenting the equipments required, the steps of the experiments and the results they have obtained for a better understanding of photosynthesis Digital pen project Electricity, Optics and English Context: Sunlight is a complex source of light based on white light that can be decomposed to explain light radiations or colours. This light is a precious source to create

  10. Radiative light dark matter

    NASA Astrophysics Data System (ADS)

    Dedes, A.; Karamitros, D.; Pilaftsis, A.

    2017-06-01

    We present a Peccei-Quinn (PQ)-symmetric two-Higgs doublet model that naturally predicts a fermionic singlet dark matter in the mass range 10 keV-1 GeV. The origin of the smallness of the mass of this light singlet fermion arises predominantly at the one-loop level, upon soft or spontaneous breakdown of the PQ symmetry via a complex scalar field in a fashion similar to the so-called Dine-Fischler-Sredniki-Zhitnitsky axion model. The mass generation of this fermionic radiative light dark matter (RLDM) requires the existence of two heavy vectorlike SU(2) isodoublets, which are not charged under the PQ symmetry. We show how the RLDM can be produced via the freeze-in mechanism, thus accounting for the missing matter in the Universe. Finally, we briefly discuss possible theoretical and phenomenological implications of the RLDM model for the strong C P problem and the CERN Large Hadron Collider (LHC).

  11. Fundamentals of Polarized Light

    NASA Technical Reports Server (NTRS)

    Mishchenko, Michael

    2003-01-01

    The analytical and numerical basis for describing scattering properties of media composed of small discrete particles is formed by the classical electromagnetic theory. Although there are several excellent textbooks outlining the fundamentals of this theory, it is convenient for our purposes to begin with a summary of those concepts and equations that are central to the subject of this book and will be used extensively in the following chapters. We start by formulating Maxwell's equations and constitutive relations for time- harmonic macroscopic electromagnetic fields and derive the simplest plane-wave solution that underlies the basic optical idea of a monochromatic parallel beam of light. This solution naturally leads to the introduction of such fundamental quantities as the refractive index and the Stokes parameters. Finally, we define the concept of a quasi-monochromatic beam of light and discuss its implications.

  12. Light Dust Devil Tracks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    14 October 2004 Many Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images exhibit wild patterns of dark streaks thought to have formed by the passage of many dust devils. The dust devils disrupt the dust coating the martian surface, leaving behind a streak. However, not all dust devils make streaks, and not all dust devil streaks are dark. Some are light---it simply depends upon which is darker, the substrate or the dust that the spinning vortex disrupts. The example of light-toned dust devil streaks shown here is located in southern Schiaparelli Basin near 5.3oS, 343.3oW. The image covers an area about 3 km (1.9 mi) across; sunlight illuminates the scene from the left/upper left.

  13. LCC: Light Curves Classifier

    NASA Astrophysics Data System (ADS)

    Vo, Martin

    2017-08-01

    Light Curves Classifier uses data mining and machine learning to obtain and classify desired objects. This task can be accomplished by attributes of light curves or any time series, including shapes, histograms, or variograms, or by other available information about the inspected objects, such as color indices, temperatures, and abundances. After specifying features which describe the objects to be searched, the software trains on a given training sample, and can then be used for unsupervised clustering for visualizing the natural separation of the sample. The package can be also used for automatic tuning parameters of used methods (for example, number of hidden neurons or binning ratio). Trained classifiers can be used for filtering outputs from astronomical databases or data stored locally. The Light Curve Classifier can also be used for simple downloading of light curves and all available information of queried stars. It natively can connect to OgleII, OgleIII, ASAS, CoRoT, Kepler, Catalina and MACHO, and new connectors or descriptors can be implemented. In addition to direct usage of the package and command line UI, the program can be used through a web interface. Users can create jobs for ”training” methods on given objects, querying databases and filtering outputs by trained filters. Preimplemented descriptors, classifier and connectors can be picked by simple clicks and their parameters can be tuned by giving ranges of these values. All combinations are then calculated and the best one is used for creating the filter. Natural separation of the data can be visualized by unsupervised clustering.

  14. Radioluminescent lighting program description

    SciTech Connect

    1987-11-01

    For more than 30 years the Department of Energy (DOE) and its predecessor agencies have conducted research and development aimed at beneficial uses of products derived from its nuclear activities. An important and promising element of radiation technology is the Program for Radioluminescent (RL) development. For years simple RL devices, such as aircraft exit signs, have served necessary functions in society. Electrons exciting phosphors and producing light is a fundamental concept to which the layman can immediately relate, while gaining a balanced perspective concerning risk and safety. DOE`s RL lighting development program has advanced the technology with infrared RL markers for helipads which are not detectable without the aid of special viewers. These devices were used to aid in the evacuation of wounded from Grenada. Visible RL airfield lighting has been used to promote aviation safety in remote Eskimo communities in Alaska, and non-electric taxiway signs and markers in the corrosive saline soils of Florida airports. The current plan is to consolidate past accomplishments and develop RL devices and systems using advanced technology for new applications. The potential for improved performance that solid-matrix RL techniques offer has stimulated interest in a variety of innovative applications for which electric lighting has long been the only practical alternative. The program described in this document is intended to provide for an optimum development and application of RL technology while supporting the transfer of this technology to the private sector and providing an institutional perspective from which the longer range applications and ramifications of this technology can be anticipated.

  15. Solar light bulb

    SciTech Connect

    Smith, D.A.

    1983-07-26

    A system for generating light directly using solar energy is provided herein. It includes a concentrator and accumulator for the sun's rays to generate a concentrated beam of visible solar radiation. A distributor shaft is provided for distributing the beam of visible solar radiation. A fork is provided in the distributor shaft to define a plurality of branch lines, each provided with a mirror at the intersection to direct the beam down the respective branch line to permit parallel fractions of the beam to be reflected off the respective mirrors and to pass down the respective branch line. A solar bulb is provided including a double walled upper bulbous portion including the inlet from the branch line and a pair of heat outlet tubes, and a double walled lower bulbous portion, the upper portion thereof being divergently reflective, with the lower portion having walls which are either transparent or translucent to provide greater light diffusion, and the space between the two walls being maintained under vacuum to provide heat insulation values. A structure is provided within the solar bulb for the absorption and radiation of the concentrated beam of visible solar radiation. Preferably structure is provided connected to the solar bulb to draw in outside air in the summer to direct it past the solar bulb and to air vent hot air produced at the solar bulb to the outside, thereby providing light with minimal heat in the summer. The same structure is operated in the winter to draw in household air to direct it past the solar bulb and to recirculate such heated air produced at the solar bulb to the house, thereby providing light and heat in the winter.

  16. Dawn's Early Light

    NASA Image and Video Library

    2017-07-10

    The light of a new day on Saturn illuminates the planet's wavy cloud patterns and the smooth arcs of the vast rings. The light has traveled around 80 minutes since it left the sun's surface by the time it reaches Saturn. The illumination it provides is feeble; Earth gets 100 times the intensity since it's roughly ten times closer to the sun. Yet compared to the deep blackness of space, everything at Saturn still shines bright in the sunlight, be it direct or reflected. This view looks toward the sunlit side of the rings from about 10 degrees above the ring plane. The image was taken with the Cassini spacecraft wide-angle camera on Feb. 25, 2017 using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 939 nanometers. The view was obtained at a distance of approximately 762,000 miles (1.23 million kilometers) from Saturn. Image scale is 45 miles (73 kilometers) per pixel. https://photojournal.jpl.nasa.gov/catalog/PIA21336

  17. Polymorphous light eruption.

    PubMed

    Hölzle, E; Plewig, G; von Kries, R; Lehmann, P

    1987-03-01

    Polymorphous light eruption (PLE) is a common photodermatosis of unknown etiology. It afflicts mainly fair-skinned patients, with a preponderance of young females. There is, however, no absolute restriction as to age, sex, or race. Clinical variants include the papular, vesiculo-bullous, and hemorrhagic variety, as well as plaque, erythema multiforme-like, and insect bite (strophulus)-like types. Skin lesions appear only in certain exposed areas hours or a few days after intense sunshine, and are nearly always monomorphous in the same patient. The rash subsides spontaneously within several days without leaving scars. The histopathologic picture is characteristic and shows a perivascular lymphocytic infiltrate in the upper and middle corium with subepidermal edema, vacuolization of basal cells, and spongiosis in the lower epidermis. The most important differential diagnoses are solar urticaria, photosensitive erythema multiforme, and lupus erythematosus. The action spectrum of PLE is under debate. Reproduction of skin lesions has been reported with UVB, UVA, and, rarely, visible light, with UVA probably being the most effective part of the spectrum. More important than treatment of PLE is prophylaxis. UVA- and UVB-effective sunscreens are of some help. Phototherapy and especially photochemotherapy (psoralen + UVA; PUVA) offer effective ways to decrease light sensitivity. Systemic treatment with chloroquine or beta-carotene has been disappointing.

  18. Nuclear light bulb

    NASA Technical Reports Server (NTRS)

    Latham, Tom

    1991-01-01

    The nuclear light bulb engine is a closed cycle concept. The nuclear light bulb concept provides containment by keeping the nuclear fuel fluid mechanically suspended in a cylindrical geometry. Thermal heat passes through an internally cooled, fused-silica, transparent wall and heats hydrogen propellant. The seeded hydrogen propellant absorbs radiant energy and is expanded through a nozzle. Internal moderation was used in the configuration which resulted in a reduced critical density requirement. This result was supported by criticality experiments. A reference engine was designed that had seven cells and was sized to fit in what was then predicted to be the shuttle bay mass and volume limitations. There were studies done of nozzle throat cooling schemes to remove the radiant heat. Elements of the nuclear light bulb program included closed loop critical assembly tests done at Los Alamos with UF6 confined by argon buffer gas. It was shown that the fuel region could be seeded with constituents that would block UV radiation from the uranium plasma. A combination of calculations and experiments showed that internal moderation produced a critical mass reduction. Other aspects of the research are presented.

  19. 'Light bar' attitude indicator

    NASA Technical Reports Server (NTRS)

    Enevoldson, E. K.; Horton, V. W.

    1982-01-01

    The development and evaluation of a light bar attitude indicator to help maintain proper aircraft attitude during high altitude night flying is described. A standard four-inch ADI was modified to project an artificial horizon across the instrument panel for pitch and roll information. A light bulb was put in the center of the ADI and a thin slit cut on the horizon, resulting in a thin horizontal sheet of light projecting from the instrument. The intensity of the projected beam is such that it can only be seen in a darkened room or at night. The beam on the instrument panel of the T-37 jet trainer is shown, depicting various attitudes. The favorable comments of about 50 pilots who evaluated the instrument are summarized, including recommendations for improving the instrument. Possible uses for the instrument to ease the pilot task are listed. Two potential problems in using the device are the development of pilot complacency and an upright-inverted ambiguity in the instrument.

  20. Fast Light Optical Gyroscopes

    NASA Technical Reports Server (NTRS)

    Smith, David D.

    2015-01-01

    Next-generation space missions are currently constrained by existing spacecraft navigation systems which are not fully autonomous. These systems suffer from accumulated dead-reckoning errors and must therefore rely on periodic corrections provided by supplementary technologies that depend on line-of-sight signals from Earth, satellites, or other celestial bodies for absolute attitude and position determination, which can be spoofed, incorrectly identified, occluded, obscured, attenuated, or insufficiently available. These dead-reckoning errors originate in the ring laser gyros themselves, which constitute inertial measurement units. Increasing the time for standalone spacecraft navigation therefore requires fundamental improvements in gyroscope technologies. One promising solution to enhance gyro sensitivity is to place an anomalous dispersion or fast light material inside the gyro cavity. The fast light essentially provides a positive feedback to the gyro response, resulting in a larger measured beat frequency for a given rotation rate as shown in figure 1. Game Changing Development has been investing in this idea through the Fast Light Optical Gyros (FLOG) project, a collaborative effort which began in FY 2013 between NASA Marshall Space Flight Center (MSFC), the U.S. Army Aviation and Missile Research, Development, and Engineering Center (AMRDEC), and Northwestern University. MSFC and AMRDEC are working on the development of a passive FLOG (PFLOG), while Northwestern is developing an active FLOG (AFLOG). The project has demonstrated new benchmarks in the state of the art for scale factor sensitivity enhancement. Recent results show cavity scale factor enhancements of approx.100 for passive cavities.

  1. Acute oral toxicity of JA-2 solid propellant in icr mice. Report for 17 December 1985-17 January 1986

    SciTech Connect

    Morgan, E.W.; Frost, D.F.; Wheller, C.R.; Korte, D.W.

    1989-12-01

    The acute oral toxicity of JA-2 Solid Propellant was determined in male and female ICR mice by using an oral gavage, split-dose method. The MLD was 3774.6 + or - 150.5 mg/kg for male mice and 3528.8 + or - 133.8 mg/kg for female mice. JA-2 produced component, diethyleneglycol dinitrate and nitroglycerin. These signs included tremors, inactivity, depression of reflexes, loss of equilibrium, opisthotonus, and increased respiratory activity. Other clinical signs observed were associated with the general malaise of the animals following dosing and included perianal staining, hunched posture, squinting, and rough coat. Most animals exhibited signs by 2 hours after dosing and either had died or the signs had cleared within 5 days of dosing. According to the classification scheme of Hodge and Sterner, these results place JA-2 in the slightly toxic class.

  2. Acute oral toxicity of ja-2 solid propellant in sprague-dawley rats. Report for 12 November-19 December 1985

    SciTech Connect

    Brown, L.D.; Justus, J.D.; Wheeler, C.R.; Korte, D.W.

    1989-12-01

    The acute oral toxicity of JA-2 Solid Propellant was determined in male and female Sprague-Dawley rats by using an oral gavage split-dose method. The MLD was 3990.6 + or - 349.7 mg/kg for male rats and 2545.9 + or - 421.1 mg/kg for female rats. JA-2 produced clinical signs that were attributed to its nitrate ester components, diethyleneglycol dinitrate and nitroglycerin. These signs included tremors and twitching, cyanosis, and increases in respiratory rate and depth. Other clinical signs observed were associated with the general malaise of the animals following dosing and included hunched posture, rough coat, reddish stains around the eyes and nose, and perianal staining. Most animals exhibited signs by 4 hours after dosing and either had died or the signs had cleared by 96 hours after dosing. According to the classification scheme of Hodge and Sterner, these results place JA-2 in the slightly toxic class.

  3. 30. BEDROOM #3 INTERIOR SHOWING 1 LIGHT OVER 1 LIGHT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. BEDROOM #3 INTERIOR SHOWING 1 LIGHT OVER 1 LIGHT WINDOW ON EAST WALL AND PARTIALLY OPENED DOOR TO WINDOWED CLOSET. VIEW TO EAST. - Big Creek Hydroelectric System, Powerhouse 8, Operator Cottage, Big Creek, Big Creek, Fresno County, CA

  4. Physics of light

    SciTech Connect

    Doria, R.

    2012-09-24

    A fourth interpretation for the principle of light invariance is proposed. After Maxwell equations, relativity, Lorentz group, another possibility stands into consider the Lorentz group representations as species. By specie one means fields with same nature under light invariance. For instance, given a ((1/2),(1/2)) representation, instead of just one specific field, we should associate to it the potential fields specie. Thus, starting from such fields specie interpretation the features of a certain potential field A{sub {mu}I} will be determined in terms of its associated fields set {l_brace}A{sub {mu}I}{r_brace}, where I means a diversity index. It says that, the original field equation to be searched for a given field description is that one corresponding to the associated group of fields, and not more, for the field being taken isolated. It introduces the meaning of parts enfolded in the whole through whole relativistic equations. There is a more primitive equation to be understood. Instead Maxwell equation this fourth light invariance interpretation is guiding us to a more basic equation describing a fields set {l_brace}A{sub {mu}I}{r_brace}. It will be entitled as Global Maxwell equation. Three steps are necessary for characterizing this Global Maxwell equation. The first one is to derive on abelian terms a generic expression for the fields set {l_brace}A{sub {mu}I}{r_brace}. Further, show the diversity between these associated fields. Prove that every field carries a different quantum number (spin, mass, charges; C, P, T, CPT). The third one is on the photon singularity. Being the light invariance porter, it should be distinguished from others fields. This is done through the group gauge directive symmetry and Noether current. A Global Lorentz force complements the Global Maxwell by introducing three types of force. The first one generalizes the usual Lorentz force while the last two introduce relationships between fields and masses and fields with fields. A

  5. More Chemistry with Light! More Light in Chemistry!

    PubMed

    Bach, Thorsten

    2015-09-21

    "…︁ Why is chemistry overlooked when talking about light? Is the photon a physical particle per se? Are all important light-induced processes biological? Maybe the role of light for chemistry and the role of chemistry for light may be far less important than a few eccentric scientists would like to believe. From the perspective of a synthetically oriented photochemist, however, the facts are different …︁" Read more in the Editorial by Thorsten Bach.

  6. Imitating Broadband Diurnal Light Variations Using Solid State Light Sources

    NASA Astrophysics Data System (ADS)

    Ferguson, Ian; Melton, Andrew; Li, Nola; Nicol, David; Park, Eun Hyun; Tosini, Gianluca

    Many studies have documented the success of light therapy in treating disorders of the human internal clock (circadian rhythm). Recent biological research has shown the importance of developing light sources that are tunable in the blue region of the spectrum for treatment to be safe and effective. A novel tunable broadband solid-state light source is presented here that mimics the diurnal variation in sunlight by modulating the intensity of blue light emission.

  7. Transcriptome sequencing and de novo analysis of cytoplasmic male sterility and maintenance in JA-CMS cotton.

    PubMed

    Yang, Peng; Han, Jinfeng; Huang, Jinling

    2014-01-01

    Cytoplasmic male sterility (CMS) is the failure to produce functional pollen, which is inherited maternally. And it is known that anther development is modulated through complicated interactions between nuclear and mitochondrial genes in sporophytic and gametophytic tissues. However, an unbiased transcriptome sequencing analysis of CMS in cotton is currently lacking in the literature. This study compared differentially expressed (DE) genes of floral buds at the sporogenous cells stage (SS) and microsporocyte stage (MS) (the two most important stages for pollen abortion in JA-CMS) between JA-CMS and its fertile maintainer line JB cotton plants, using the Illumina HiSeq 2000 sequencing platform. A total of 709 (1.8%) DE genes including 293 up-regulated and 416 down-regulated genes were identified in JA-CMS line comparing with its maintainer line at the SS stage, and 644 (1.6%) DE genes with 263 up-regulated and 381 down-regulated genes were detected at the MS stage. By comparing the two stages in the same material, there were 8 up-regulated and 9 down-regulated DE genes in JA-CMS line and 29 up-regulated and 9 down-regulated DE genes in JB maintainer line at the MS stage. Quantitative RT-PCR was used to validate 7 randomly selected DE genes. Bioinformatics analysis revealed that genes involved in reduction-oxidation reactions and alpha-linolenic acid metabolism were down-regulated, while genes pertaining to photosynthesis and flavonoid biosynthesis were up-regulated in JA-CMS floral buds compared with their JB counterparts at the SS and/or MS stages. All these four biological processes play important roles in reactive oxygen species (ROS) homeostasis, which may be an important factor contributing to the sterile trait of JA-CMS. Further experiments are warranted to elucidate molecular mechanisms of these genes that lead to CMS.

  8. Pollution-free road lighting

    NASA Astrophysics Data System (ADS)

    Schreuder, Duco A.

    They relate to reducing road accidents and some forms of crime but also enhance the social safety of residents and pedestrians and the amenity for residents. Road traffic in developing countries is much more hazardous than in industrialized countries. Accident rates in 'low' income countries may be as much as 35 times higher than in 'high' income countries. Thus, it might be much more cost-effective to light roads in the developing world than in the industrialized world. Fighting light pollution is more pressing in developing countries as most of the major high-class astronomical observatories are there. Astronomical observations are disturbed by light from outdoor lighting installations, part of which is scattered in the atmosphere to form 'sky glow'. The International Lighting Commission CIE has published a Technical Report giving general guidance for lighting designers and policy makers on the reduction of the sky glow. Lighting improves visibility, essential for almost all human activity. However, light that hits the road contributes to visibility only if it is reflected. In poorly designed lighting equipment much of the lumen output of the lamps is sent directly upwards. This can be avoided by properly defined light fittings. The light output of fittings is determined by their optical quality and by the installation maintenance factor. Open fittings are to be preferred. If mounted horizontally, they make street lighting with the least light pollution.

  9. Light pollution simulations for planar ground-based light sources.

    PubMed

    Kocifaj, Miroslav

    2008-02-20

    The light pollution model is employed to analyze spatial behavior of luminance at the night sky under cloudless and overcast conditions. Enhanced light excess is particularly identified at cloudy skies, because the clouds efficiently contribute to the downward luminous flux. It is evident that size of ground-based light sources can play an important role in the case of overcast sky conditions. Nevertheless, the realistically sized light sources are rarely embedded into light pollution modeling, and rather they are replaced by simple point sources. We discuss the discrepancies between sky luminance distributions when at first the planar light sources are considered and at second the point-source approximation is accepted. The found differences are noticeable if the size of the light source, distance to the observer, and altitude of a cloudy layer are comparable one to the other. Compared with point-source approximation, an inclusion of the size factor into modeling the light sources leads to partial elimination of the steep changes of sky luminance (typical for point sources of light). The narrow and sharp light pillars normally presented on the sky illuminated by point light sources can disappear or fuse together when two or more nearby light sources are considered with their real sizes. Sky elements situated close to the horizon will glow efficiently if luminous flux originates from two-dimensional ground-based entities (such as cities or villages).

  10. Light Phenomena over the ESO Observatories III: Zodiacal Light

    NASA Astrophysics Data System (ADS)

    Horálek, P.; Christensen, L. L.; Nesvorný, D.; Davies, R.

    2016-06-01

    The zodiacal light is often seen at the ESO observatories in the hours after sunset and before sunrise. The origin of the zodiacal light is described and recent research briefly summarised. Some fine images of the zodiacal light from Paranal and La Silla, including the full extent of the night sky are presented.

  11. 2. Southern Light Tower and Northern Light Tower, view north, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Southern Light Tower and Northern Light Tower, view north, south sides - Kennebec River Light Station, South side of Doubling Point Road, off State Highway 127, 1.8 miles south of U.S. Route 1, Arrowsic, Sagadahoc County, ME

  12. Organic light emitting diode with light extracting layer

    DOEpatents

    Lu, Songwei

    2016-06-14

    A light extraction substrate includes a glass substrate having a first surface and a second surface. A light extraction layer is formed on at least one of the surfaces. The light extraction layer is a coating, such as a silicon-containing coating, incorporating nanoparticles.

  13. Dance of the Light Echoes

    NASA Image and Video Library

    2008-05-29

    This composite image from NASA Spitzer Space Telescope shows the remnant of a star that exploded, called Cassiopeia A center and its surrounding light echoes -- dances of light through dusty clouds, created when stars blast apart.

  14. The Control of Lighting Heat

    ERIC Educational Resources Information Center

    Modern Schools, 1973

    1973-01-01

    The trend toward increased lighting has accelerated the acceptance of heat recovery systems. A heating-lighting-cooling system is a responsible and efficient use of energy for future school buildings. (Author/MLF)

  15. Skin - abnormally dark or light

    MedlinePlus

    ... ency/article/003242.htm Skin - abnormally dark or light To use the sharing features on this page, ... the hands. The bronze color can range from light to dark (in fair-skinned people) with the ...

  16. Campus Lighting: A Better Way

    ERIC Educational Resources Information Center

    American School and University, 1977

    1977-01-01

    The lighting design at the Northwest Campus of Tarrant County Junior College in Texas helped put the campus at the top of the state's list of energy-efficient buildings. One factor is tight time control of lights. (Author)

  17. Issues of Rural Light Pollution

    NASA Astrophysics Data System (ADS)

    Osborn, W. H.; Hammer, R. L.; Hammer, A.

    2001-12-01

    Light pollution is generally considered mostly an urban problem. Common sources of light pollution are poorly designed lighting of streets, parking lots, businesses and advertizing signs and for security. These sources, and the amount of light pollution generated, increase with population density. Nevertheless, light pollution can also be significant in rural areas. Rural light pollution differs from that in urban settings, both in the types of pollution and in the means that must be employed to control it. In the country the offending sources are often isolated lights such as from farm barns, vacation cottages, radio and cell phone towers, and road intersections. A culture of strong property rights and privacy rights affects attempts to control rural light pollution. We describe how some of these issues may be addressed based on the results from an Eagle Scout project carried out in central Michigan.

  18. Lighting for Safety and Security.

    ERIC Educational Resources Information Center

    Fleming, Colette

    2000-01-01

    Discusses ways to use lighting to provide a safe environment, reduce vandalism, improve visibility, and reduce overall liability for colleges. Guidelines for outdoor, parking, and emergency lighting are discussed. (GR)

  19. Lighting for Today and Tomorrow.

    ERIC Educational Resources Information Center

    Murphy, Peter

    2000-01-01

    Discusses how technology has contributed to brighter, less expensive, and more efficient lighting. Four key areas where suspended Direct/Indirect lighting out performs parabolic troffers are examined. (GR)

  20. Lighting for Today and Tomorrow.

    ERIC Educational Resources Information Center

    Murphy, Peter

    2000-01-01

    Discusses how technology has contributed to brighter, less expensive, and more efficient lighting. Four key areas where suspended Direct/Indirect lighting out performs parabolic troffers are examined. (GR)

  1. Lighting for Safety and Security.

    ERIC Educational Resources Information Center

    Fleming, Colette

    2000-01-01

    Discusses ways to use lighting to provide a safe environment, reduce vandalism, improve visibility, and reduce overall liability for colleges. Guidelines for outdoor, parking, and emergency lighting are discussed. (GR)

  2. Perfect Lighting for Facial Photography in Aesthetic Surgery: Ring Light.

    PubMed

    Dölen, Utku Can; Çınar, Selçuk

    2016-04-01

    Photography is indispensable for plastic surgery. On-camera flashes can result in bleached out detail and colour. This is why most of the plastic surgery clinics prefer studio lighting similar to professional photographers'. In this article, we want to share a simple alternative to studio lighting that does not need extra space: Ring light. We took five different photographs of the same person with five different camera and lighting settings: Smartphone and ring light; point and shoot camera and on-camera flash; point and shoot camera and studio lighting; digital single-lens reflex (DLSR) camera and studio lighting; DSLR and ring light. Then, those photographs were assessed objectively with an online survey of five questions answered by three distinct populations: plastic surgeons (n: 28), professional portrait photographers (n: 24) and patients (n: 22) who had facial aesthetic procedures. Compared to the on-camera flash, studio lighting better showed the wrinkles of the subject. The ring light facilitated the perception of the wrinkles by providing homogenous soft light in a circular shape rather than bursting flashes. The combination of a DSLR camera and ring light gave the oldest looking subject according to 64 % of responders. The DSLR camera and the studio lighting demonstrated the youngest looking subject according to 70 % of the responders. The majority of the responders (78 %) chose the combination of DSLR camera and ring light that exhibited the wrinkles the most. We suggest using a ring light to obtain well-lit photographs without loss of detail, with any type of cameras. However, smartphones must be avoided if standard pictures are desired. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

  3. Light curves of light rays passing through a wormhole

    NASA Astrophysics Data System (ADS)

    Tsukamoto, Naoki; Harada, Tomohiro

    2017-01-01

    Gravitational lensing is a good probe into the topological structure of dark gravitating celestial objects. In this paper, we investigate the light curve of a light ray that passes through the throat of an Ellis wormhole, the simplest example of traversable wormholes. The method developed here is also applicable to other traversable wormholes. To study whether the light curve of a light ray that passes through a wormhole throat is distinguishable from that which does not, we also calculate light curves without the passage of a throat for an Ellis wormhole, a Schwarzschild black hole, and an ultrastatic wormhole with the spatial geometry identical to that of the Schwarzschild black hole in the following two cases: (i) "microlensing," where the source, lens, and observer are almost aligned in this order and the light ray starts at the source, refracts in the weak gravitational field of the lens with a small deflection angle, and reaches the observer; and (ii) "retrolensing," where the source, observer, and lens are almost aligned in this order, and the light ray starts at the source, refracts in the vicinity of the light sphere of the lens with a deflection angle very close to π , and reaches the observer. We find that the light curve of the light ray that passes through the throat of the Ellis wormhole is clearly distinguishable from that by the microlensing but not from that by the retrolensing. This is because the light curve of a light ray that passes by a light sphere of a lens with a large deflection angle has common characters, irrespective of the details of the lens object. This implies that the light curves of the light rays that pass through the throat of more general traversable wormholes are qualitatively the same as that of the Ellis wormhole.

  4. Tomographic imaging with polarized light.

    PubMed

    Soloviev, Vadim Y; Zacharakis, Giannis; Spiliopoulos, George; Favicchio, Rosy; Correia, Teresa; Arridge, Simon R; Ripoll, Jorge

    2012-06-01

    We report three-dimensional tomographic reconstruction of optical parameters for the mesoscopic light scattering regime from experimentally obtained datasets by using polarized light. We present a numerically inexpensive approximation to the radiative transfer equation governing the polarized light transport. This approximation is employed in the reconstruction algorithm, which computes two optical parameters by using parallel and perpendicular polarizations of transmitted light. Datasets were obtained by imaging a scattering phantom embedding highly absorbing inclusions. Reconstruction results are presented and discussed.

  5. Joint Light Tactical Vehicle (JLTV)

    DTIC Science & Technology

    2015-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-279 Joint Light Tactical Vehicle (JLTV) As of FY 2017 President’s Budget Defense Acquisition...mail.mil Phone: 586-239-2984 Fax: DSN Phone: 273-2984 DSN Fax: Date Assigned: July 8, 2015 Program Information Program Name Joint Light Tactical...Description The primary mission of the Joint Light Tactical Vehicle (JLTV) is to provide protected, sustained, and networked light tactical mobility to the

  6. Photodetector with enhanced light absorption

    DOEpatents

    Kane, James

    1985-01-01

    A photodetector including a light transmissive electrically conducting layer having a textured surface with a semiconductor body thereon. This layer traps incident light thereby enhancing the absorption of light by the semiconductor body. A photodetector comprising a textured light transmissive electrically conducting layer of SnO.sub.2 and a body of hydrogenated amorphous silicon has a conversion efficiency about fifty percent greater than that of comparative cells. The invention also includes a method of fabricating the photodetector of the invention.

  7. Light sensitivity of methanogenic archaebacteria

    SciTech Connect

    Olson, K.D.; McMahon, C.W.; Wolfe, R.S. )

    1991-09-01

    Representatives of four families of methanogenic archaebacteria (archaea), Methanobacterium thermoautotrophicum {Delta}H, Methanobacterium thermoautotrophicum Marburg, Methanosarcina acetivorans, Methanococcus voltae, and Methanomicrobium mobile, were found to be light sensitive. The facultative anaerobic eubacteria Escherichia coli and Salmonella typhimurium, however, were tolerant of light when grown anaerobically under identical light conditions. Interference filters were used to show that the growth of the methanogens is inhibited by light in the blue end of the visible spectrum (370 to 430 nm).

  8. LIGHT-PENCIL COORDINATE POSITIONER,

    DTIC Science & Technology

    information sources such as radar and IFF PPI repeaters and computer displays. A light pencil which detects and controls a positionand intensity...position the video gate which extracts desired signals from the radar/IFF returns without requiring the operator to hold the pencil in position. The light ...to-one light pencil motion to marker motion. Except for the light detection photomultipler, the entire design is solid state. (Author)

  9. Jupiter's Northern Lights

    NASA Image and Video Library

    2017-09-06

    This is a reconstructed view of Jupiter's northern lights through the filters of Juno's Ultraviolet Imaging Spectrometer (UVS) instrument on Dec. 11, 2016, as the Juno spacecraft approached Jupiter, passed over its poles, and plunged towards the equator. Such measurements present a real challenge for the spacecraft's science instruments: Juno flies over Jupiter's poles at 30 miles (50 kilometers) per second -- more than 100,000 miles per hour -- speeding past auroral forms in a matter of seconds. https://photojournal.jpl.nasa.gov/catalog/PIA21938

  10. Pedestrian Friendly Outdoor Lighting

    SciTech Connect

    Miller, Naomi J.; Koltai, Rita; McGowan, Terry

    2013-12-31

    This GATEWAY report discusses the problems of pedestrian lighting that occur with all technologies with a focus on the unique optical options and opportunities offered by LEDs through the findings from two pedestrian-focused projects, one at Stanford University in California, and one at the Chautauqua Institution in upstate New York. Incorporating user feedback this report reviews the tradeoffs that must be weighed among visual comfort, color, visibility, efficacy and other factors to stimulate discussion among specifiers, users, energy specialists, and in industry in hopes that new approaches, metrics, and standards can be developed to support pedestrian-focused communities, while reducing energy use.

  11. INTERMITTENT STIMULATION BY LIGHT

    PubMed Central

    Hecht, Selig; Verrijp, Cornelis D.

    1933-01-01

    A theoretical treatment of the data of intermittent stimulation by light is presented in terms of the familiar reversible photochemical system previously used for other properties of vision. It appears that such a system considered merely as the initial event in photoreception is capable of giving a first order quantitative description of the relation between critical frequency and illumination for different retinal regions, and of Talbot's law. Moreover the development of this concept shows that the general form of most of the existing relationships in flicker are already apparent in the characteristics of the behavior of this initial photochemical event. PMID:19872778

  12. "Light sail" acceleration reexamined.

    PubMed

    Macchi, Andrea; Veghini, Silvia; Pegoraro, Francesco

    2009-08-21

    The dynamics of the acceleration of ultrathin foil targets by the radiation pressure of superintense, circularly polarized laser pulses is investigated by analytical modeling and particle-in-cell simulations. By addressing self-induced transparency and charge separation effects, it is shown that for "optimal" values of the foil thickness only a thin layer at the rear side is accelerated by radiation pressure. The simple "light sail" model gives a good estimate of the energy per nucleon, but overestimates the conversion efficiency of laser energy into monoenergetic ions.

  13. Coherent white light amplification

    DOEpatents

    Jovanovic, Igor; Barty, Christopher P.

    2004-05-25

    A system for coherent simultaneous amplification of a broad spectral range of light that includes an optical parametric amplifier and a source of a seed pulse is described. A first angular dispersive element is operatively connected to the source of a seed pulse. A first imaging telescope is operatively connected to the first angular dispersive element and operatively connected to the optical parametric amplifier. A source of a pump pulse is operatively connected to the optical parametric amplifier. A second imaging telescope is operatively connected to the optical parametric amplifier and a second angular dispersive element is operatively connected to the second imaging telescope.

  14. Tunnel of light

    NASA Astrophysics Data System (ADS)

    Ohlmann, Dietmar

    1998-02-01

    When I made the decision to give up science for becoming a painter I could not imagine that I would paint light. In the 2nd year of my fine art studies I had my first contact with holography, thanks to my former tutor, Roddney Murray at the Liverpool School of Art. During the MA course of the RCA in London I knew that the potential of holography was far beyond our present perception. Since I had the opportunity to work in large scale, doing architectural installation, I have got certain that holography and diffraction media would set new trends into the arts and society.

  15. Slow Light Semiconductor Laser

    DTIC Science & Technology

    2015-02-02

    we demonstrate a semiconductor laser with a spectral linewidth of 18 kHz in the telecom band around 1:55um. The views, opinions and/or findings...we demonstrate a semiconductor laser with a spectral linewidth of 18 kHz in the telecom band around 1:55um. Further, the large intracavity field...hybrid Si/III- V platforms Abstract The semiconductor laser is the principal light source powering the world-wide optical fiber network . Ever

  16. Light-toned Terraces

    NASA Technical Reports Server (NTRS)

    2006-01-01

    29 May 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows light-toned, layered, sedimentary rock outcrops in northwest Schiaparelli Basin. The layers are all of about the same thickness (a few meters or less) and appear to have similar properties. They were likely deposited in an episodic or cyclic manner, perhaps in an underwater setting.

    Location near: 1.2oS, 346.3oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Autumn

  17. Transforming Light with Metamaterials

    NASA Astrophysics Data System (ADS)

    Shalaev, Vladimir

    2009-03-01

    Metamaterials are expected to open a gateway to unprecedented electromagnetic properties and functionality unattainable from naturally occurring materials, thus enabling a family of new ``meta-devices.'' We review this new emerging field and significant progress in developing metamaterials for the optical part of the spectrum. Specifically, we describe recently demonstrated artificial magnetism across the whole visible, negative-index in the optical range, and promising approaches along with challenges in realizing optical cloaking. A new paradigm of engineering space for light with transformation optics will be also discussed.

  18. Lighted, Folding Inspection Mirror

    NASA Technical Reports Server (NTRS)

    Roepe, Brian E.

    1991-01-01

    Compact, inexpensive tool used in place of expensive borescopes. Shortens inspection/photographing process. Includes two small metal or glass mirrors hinged together. Two 3-V light bulbs attached along edges of one mirror and connected to battery of two cells. Inserted into narrow opening of clevis or tand, and surface viewed and photographed in opposite mirror. Useful in assembly of segments of solid rocket motors as well as in postflight assessment, engineering evaluation, and refurbishment. Also applied in general to inspection and photographing of inner sealing surfaces to which access difficult.

  19. Light duty utility arm

    SciTech Connect

    1998-12-01

    The Light-Duty Utility Arm (LDUA) System is a mobile, multi-axis positioning system capable of deploying tools and sensors (end effecters) inside radioactive waste tanks for tank wall inspection, waste characterization, and waste retrieval. The LDUA robotic manipulator enters a tank through existing openings (risers) in the tank dome of the underground tanks. Using various end effecters, the LDUA System is a versatile system for high-level waste tank remediation. The LDUA System provides a means to deploy tools, while increasing the technology resources available to the U.S. Department of Energy (DOE). Ongoing end effecter development will provide additional capabilities to remediate the waste tanks.

  20. 'Light Sail' Acceleration Reexamined

    SciTech Connect

    Macchi, Andrea; Veghini, Silvia; Pegoraro, Francesco

    2009-08-21

    The dynamics of the acceleration of ultrathin foil targets by the radiation pressure of superintense, circularly polarized laser pulses is investigated by analytical modeling and particle-in-cell simulations. By addressing self-induced transparency and charge separation effects, it is shown that for 'optimal' values of the foil thickness only a thin layer at the rear side is accelerated by radiation pressure. The simple 'light sail' model gives a good estimate of the energy per nucleon, but overestimates the conversion efficiency of laser energy into monoenergetic ions.

  1. Lighting with laser diodes

    NASA Astrophysics Data System (ADS)

    Basu, Chandrajit; Meinhardt-Wollweber, Merve; Roth, Bernhard

    2013-08-01

    Contemporary white light-emitting diodes (LEDs) are much more efficient than compact fluorescent lamps and hence are rapidly capturing the market for general illumination. LEDs are also replacing halogen lamps or even newer xenon based lamps in automotive headlamps. Because laser diodes are inherently much brighter and often more efficient than corresponding LEDs, there is great research interest in developing laser diode based illumination systems. Operating at higher current densities and with smaller form factors, laser diodes may outperform LEDs in the future. This article reviews the possibilities and challenges in the integration of visible laser diodes in future illumination systems.

  2. [Blue light and eye health].

    PubMed

    Zou, Leilei; Dai, Jinhui

    2015-01-01

    Blue light, with the wavelength between 400 nm and 500 nm, has caused public concern because of the injury to the retinal cells. Meanwhile, it is important in circadian rhythm regulation, scotopic vision and ocular growth. Is the blue light safe? Should it be eliminated from the daily life? Here we review the effect and safety of the blue light.

  3. Bright Ideas for Measuring Light.

    ERIC Educational Resources Information Center

    Amend, John R.; Schuler, John A.

    1983-01-01

    Describes an inexpensive device (around $8.00) for measuring light. The circuit used includes five resistors, three small capacitors, a cadmium sulfide light sensor, two integrated circuits, and two light-emitting diodes. The unit is constructed on a small perforated circuit board and powered by a 9-V transistor radio battery. (JN)

  4. Measuring Light with Useful Tools

    ERIC Educational Resources Information Center

    Peek, Gina; Hebert, Paulette; Frazier, Robert Scott; Knag, Mihyun

    2013-01-01

    Lighting, a necessary part of our home and work environment, is often considered as an afterthought. This article describes tools that Extension educators (Agriculture, Family and Consumer Sciences, and 4-H) can use to measure light levels. 4-H youth may also participate. These tools include light meters and Illuminating Engineering Society (IES)…

  5. Shining a Light on Savings.

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2000-01-01

    Discusses how schools and universities can save energy and money by evaluating lighting systems and changing behaviors. Retrofitting older buildings with better lighting technology and use of natural light are examined. An example of an energy conservation education program to reduce energy waste is highlighted. (GR)

  6. Measuring Light with Useful Tools

    ERIC Educational Resources Information Center

    Peek, Gina; Hebert, Paulette; Frazier, Robert Scott; Knag, Mihyun

    2013-01-01

    Lighting, a necessary part of our home and work environment, is often considered as an afterthought. This article describes tools that Extension educators (Agriculture, Family and Consumer Sciences, and 4-H) can use to measure light levels. 4-H youth may also participate. These tools include light meters and Illuminating Engineering Society (IES)…

  7. Bright Ideas for Measuring Light.

    ERIC Educational Resources Information Center

    Amend, John R.; Schuler, John A.

    1983-01-01

    Describes an inexpensive device (around $8.00) for measuring light. The circuit used includes five resistors, three small capacitors, a cadmium sulfide light sensor, two integrated circuits, and two light-emitting diodes. The unit is constructed on a small perforated circuit board and powered by a 9-V transistor radio battery. (JN)

  8. Energy saver for industrial lighting

    NASA Technical Reports Server (NTRS)

    Arline, J.; Lapalme, J.; Warren, C.

    1980-01-01

    Electronic controller switches lights on or off in response to amount of sunlight available. Is application in offices and industrial installations where electrical energy is wasted by using artificial light in sunlit areas. Device utilizes electronic monitor that varies artificial lighting according to amount of sunlight in given area.

  9. Shedding Light on the Subject.

    ERIC Educational Resources Information Center

    Keller, Brian A.

    1998-01-01

    Presents an activity in which students use mathematical ideas to understand how the intensity of light changes as light passes through water or similar partial barriers, by using a calculator-based laboratory device to record light intensity. Continues with a structured series of questions involving the use of difference equations with which…

  10. Light, Gravity and Black Holes

    ERIC Educational Resources Information Center

    Falla, David

    2012-01-01

    The nature of light and how it is affected by gravity is discussed. Einstein's prediction of the deflection of light as it passes near the Sun was verified by observations made during the solar eclipse of 1919. Another prediction was that of gravitational redshift, which occurs when light emitted by a star loses energy in the gravitational field…

  11. TODAY'S CONCEPTS IN SCHOOL LIGHTING.

    ERIC Educational Resources Information Center

    GIBSON, CHARLES D.

    SEVERAL SCHOOL LIGHTING CONCEPTS ARE PRESENTED IN THIS ARTICLE. THEY ARE AS FOLLOWS--(1) NONCAPTIVE RESEARCH SHOULD BE CARRIED ON THROUGH COORDINATION BETWEEN RESEARCH AND APPLICATION SEGMENTS OF THE LIGHTING INDUSTRY, (2) COMMUNICATION AND JOINT EFFORT SHOULD PROVIDE THAT MAJOR AGENCIES INVOLVED IN THE APPLICATION OF LIGHTING DESIGN CRITERIA HAVE…

  12. Shining a Light on Savings.

    ERIC Educational Resources Information Center

    Kennedy, Mike

    2000-01-01

    Discusses how schools and universities can save energy and money by evaluating lighting systems and changing behaviors. Retrofitting older buildings with better lighting technology and use of natural light are examined. An example of an energy conservation education program to reduce energy waste is highlighted. (GR)

  13. Light, Gravity and Black Holes

    ERIC Educational Resources Information Center

    Falla, David

    2012-01-01

    The nature of light and how it is affected by gravity is discussed. Einstein's prediction of the deflection of light as it passes near the Sun was verified by observations made during the solar eclipse of 1919. Another prediction was that of gravitational redshift, which occurs when light emitted by a star loses energy in the gravitational field…

  14. TODAY'S CONCEPTS IN SCHOOL LIGHTING.

    ERIC Educational Resources Information Center

    GIBSON, CHARLES D.

    SEVERAL SCHOOL LIGHTING CONCEPTS ARE PRESENTED IN THIS ARTICLE. THEY ARE AS FOLLOWS--(1) NONCAPTIVE RESEARCH SHOULD BE CARRIED ON THROUGH COORDINATION BETWEEN RESEARCH AND APPLICATION SEGMENTS OF THE LIGHTING INDUSTRY, (2) COMMUNICATION AND JOINT EFFORT SHOULD PROVIDE THAT MAJOR AGENCIES INVOLVED IN THE APPLICATION OF LIGHTING DESIGN CRITERIA HAVE…

  15. Light Converting Inorganic Phosphors for White Light-Emitting Diodes

    PubMed Central

    Chen, Lei; Lin, Chun-Che; Yeh, Chiao-Wen; Liu, Ru-Shi

    2010-01-01

    White light-emitting diodes (WLEDs) have matched the emission efficiency of florescent lights and will rapidly spread as light source for homes and offices in the next 5 to 10 years. WLEDs provide a light element having a semiconductor light emitting layer (blue or near-ultraviolet (nUV) LEDs) and photoluminescence phosphors. These solid-state LED lamps, rather than organic light emitting diode (OLED) or polymer light-emitting diode (PLED), have a number of advantages over conventional incandescent bulbs and halogen lamps, such as high efficiency to convert electrical energy into light, reliability and long operating lifetime. To meet with the further requirement of high color rendering index, warm light with low color temperature, high thermal stability and higher energy efficiency for WLEDs, new phosphors that can absorb excitation energy from blue or nUV LEDs and generate visible emissions efficiently are desired. The criteria of choosing the best phosphors, for blue (450−480 nm) and nUV (380−400 nm) LEDs, strongly depends on the absorption and emission of the phosphors. Moreover, the balance of light between the emission from blue-nUV LEDs and the emissions from phosphors (such as yellow from Y3Al5O12:Ce3+) is important to obtain white light with proper color rendering index and color temperature. Here, we will review the status of phosphors for LEDs and prospect the future development.

  16. Visualization of the light injection in one dimensional Photonic Crystals.

    NASA Astrophysics Data System (ADS)

    Archuleta-Garcia, Raul

    2005-03-01

    In this work we present time variation simulations of the light injection in one dimension photonic crystals (1D-PC). This phenomenon is due to the coupling of an incoming plane-wave to the discrete vibration modes in finite 1D-PC. In order to present a live animation of the system we proceed in two stages. First, we present the discrete relation dispersion and then we choose the better combination of frequency and wave-vector. Second, for this combination we reconstruct the field amplitudes in each one of the media. This phenomenon has been described in three previous works [1-3] for the case of a metal-dielectric-metal system. In this work we present the simulation of this system and also the extension of the idea for the case of a multilayer system. The visualization of the electromagnetic field gives a better comprehension of the phenomena. [1]R. Garcia-Llamas, J.A. Gaspar-Armenta, F.Ramos-Mendieta, R.F. Haglund, R. Ruiz. ``Design, manufacturing and testing of planar optical waveguide devices'',.), Proceedings of SPIE, vol. 4439, 2001, pp 88-94. [2] F. Villa, T. Lopez-Rios, L.E. Regalado, ``Electromagnetic modes in metal-insulator-metal structures'', Phys. Rev. B 63 (2001) 165103. [3] A.S. Ramirez-Duverger, R. Garcia-Llamas, ``Light scattering from a multimode waveguide of planar metalic walls'', Optics Communications, (2003)

  17. Banana fruit VQ motif-containing protein5 represses cold-responsive transcription factor MaWRKY26 involved in the regulation of JA biosynthetic genes

    PubMed Central

    Ye, Yu-Jie; Xiao, Yun-Yi; Han, Yan-Chao; Shan, Wei; Fan, Zhong-Qi; Xu, Qun-Gang; Kuang, Jian-Fei; Lu, Wang-Jin; Lakshmanan, Prakash; Chen, Jian-Ye

    2016-01-01

    Most harvested fruits and vegetables are stored at low temperature but many of them are highly sensitive to chilling injury. Jasmonic acid (JA), a plant hormone associated with various stress responses, is known to reduce chilling injury in fruits. However, little is known about the transcriptional regulation of JA biosynthesis in relation to cold response of fruits. Here, we show the involvement of a Group I WRKY transcription factor (TF) from banana fruit, MaWRKY26, in regulating JA biosynthesis. MaWRKY26 was found to be nuclear-localized with transcriptional activation property. MaWRKY26 was induced by cold stress or by methyl jasmonate (MeJA), which enhances cold tolerance in banana fruit. More importantly, MaWRKY26 transactivated JA biosynthetic genes MaLOX2, MaAOS3 and MaOPR3 via binding to their promoters. Further, MaWRKY26 physically interacted with a VQ motif-containing protein MaVQ5, and the interaction attenuated MaWRKY26-induced transactivation of JA biosynthetic genes. These results strongly suggest that MaVQ5 might act as a repressor of MaWRKY26 in activating JA biosynthesis. Taken together, our findings provide new insights into the transcriptional regulation of JA biosynthesis in response to cold stress and a better understanding of the molecular aspects of chilling injury in banana fruit. PMID:27004441

  18. HiJaK: the high-resolution J, H and K spectrometer

    NASA Astrophysics Data System (ADS)

    Muirhead, Philip S.; Hall, Zachary J.; Veyette, Mark J.

    2014-08-01

    We present the science drivers, design requirements and a preliminary design for a high-resolution, broad- bandwidth, slit-fed cross-dispersed near-infrared spectrometer for 5-meter-class telescopes. Our concept, called the High-Resolution J, H and K Spectrometer, or HiJaK, utilizes an R6 echelle in a white-pupil design to achieve high resolution in a compact configuration with a 2048 x 2048 pixel infrared detector. We present a preliminary ray-traced optical design matched to the new 4.3-meter Discovery Channel Telescope in Happy Jack, Arizona. We also discuss mechanical and cryogenic options to house our optical design.

  19. Light Scattering by Spheroids

    NASA Astrophysics Data System (ADS)

    Xie, Ya-Ming; Ji, Xia

    Nowadays, with the development of technology, particles with size at nanoscale have been synthesized in experiments. It is noticed that anisotropy is an unavoidable problem in the production of nanospheres. Besides, nonspherical nanoparticles have also been extensively used in experiments. Comparing with spherical model, spheroidal model can give a better description for the characteristics of nonspherical particles. Thus the study of analytical solution for light scattering by spheroidal particles has practical implications. By expanding incident, scattered, and transmitted electromagnetic fields in terms of appropriate vector spheroidal wave functions, an analytic solution is obtained to the problem of light scattering by spheroids. Unknown field expansion coefficients can be determined with the combination of boundary conditions and rotational-translational addition theorems for vector spheroidal wave functions. Based on the theoretical derivation, a Fortran code has been developed to calculate the extinction cross section and field distribution, whose results agree well with those obtain by FDTD simulation. This research is supported by the National Natural Science Foundation of China No. 91230203.

  20. Eye Surgery Light

    NASA Technical Reports Server (NTRS)

    1978-01-01

    During eye surgery, the surgeon uses an illuminating instrument called an opthalmoscope for close examination of the retina or the interior of the eye. Ordinarily, electric power for the head-mounted light is supplied through a cord from an overhead swivel arm or a floor pedestal. Within limits of cord length and swivel arm movement, the surgeon has considerable freedom of motion. But when more than one opthalmoscope is involved, tangling and interference of the power cords becomes a problem. St. Luke's Hospital, Cleveland, Ohio asked Lewis Research Center for assistance in finding a solution. Lewis responded with a battery-powered system that totally frees the surgeon of attached cords and swivels. Borrowing from space technology, Lewis used small, lightweight nickel-cadmium batteries that can deliver high intensity light for an hour and can be recharged overnight. The Opthalmoscope Powerpack consists of eight batteries in three containers affixed to a webbed belt, and a novel on-off switch equipped with a springloaded plexiglass "flapper." The belt pack is worn underneath the surgical gown and the flapper permits the doctor to activate the switch by elbow pressure. Lewis built five units and they have been in service at St. Luke's Hospital for a year. Used for routine examinations as well as for surgery, they have demonstrated excellent reliability.

  1. Eye Surgery Light

    NASA Technical Reports Server (NTRS)

    1978-01-01

    During eye surgery, the surgeon uses an illuminating instrument called an opthalmoscope for close examination of the retina or the interior of the eye. Ordinarily, electric power for the head-mounted light is supplied through a cord from an overhead swivel arm or a floor pedestal. Within limits of cord length and swivel arm movement, the surgeon has considerable freedom of motion. But when more than one opthalmoscope is involved, tangling and interference of the power cords becomes a problem. St. Luke's Hospital, Cleveland, Ohio asked Lewis Research Center for assistance in finding a solution. Lewis responded with a battery-powered system that totally frees the surgeon of attached cords and swivels. Borrowing from space technology, Lewis used small, lightweight nickel-cadmium batteries that can deliver high intensity light for an hour and can be recharged overnight. The Opthalmoscope Powerpack consists of eight batteries in three containers affixed to a webbed belt, and a novel on-off switch equipped with a spring-loaded plexiglass 'flapper.' The belt pack is worn underneath the surgical gown and the flapper permits the doctor to activate the switch by elbow pressure. Lewis built five units and they have been in service at St. Luke's Hospital for a year. Used for routine examinations as well as for surgery, they have demonstrated excellent reliability.

  2. Basking in Light

    NASA Image and Video Library

    2016-12-26

    Sunlight truly has come to Saturn's north pole. The whole northern region is bathed in sunlight in this view from late 2016, feeble though the light may be at Saturn's distant domain in the solar system. The hexagon-shaped jet-stream is fully illuminated here. In this image, the planet appears darker in regions where the cloud deck is lower, such the region interior to the hexagon. Mission experts on Saturn's atmosphere are taking advantage of the season and Cassini's favorable viewing geometry to study this and other weather patterns as Saturn's northern hemisphere approaches Summer solstice. This view looks toward the sunlit side of the rings from about 51 degrees above the ring plane. The image was taken with the Cassini spacecraft wide-angle camera on Sept. 9, 2016 using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 728 nanometers. The view was obtained at a distance of approximately 750,000 miles (1.2 million kilometers) from Saturn. Image scale is 46 miles (74 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA20513

  3. Landscapes Impacted by Light

    NASA Astrophysics Data System (ADS)

    Arellano, B.; Roca, J.

    2016-06-01

    The gradual spread of urbanization, the phenomenon known under the term urban sprawl, has become one of the paradigms that have characterized the urban development since the second half of the twentieth century and early twenty-first century. However, there is no unanimous consensus about what means "urbanization". The plurality of forms of human settlement on the planet difficult to identify the urbanization processes. The arrival of electrification to nearly every corner of the planet is certainly the first and more meaningful indicator of artificialization of land. In this sense, the paper proposes a new methodology based on the analysis of the satellite image of nighttime lights designed to identify the highly impacted landscapes worldwide and to build an index of Land Impacted by Light per capita (LILpc) as an indicator of the level of urbanization. The used methodology allows the identification of different typologies of urbanized areas (villages, cities or metropolitan areas), as well as "rural", "rurban", "periurban" and "central" landscapes. The study identifies 186,134 illuminated contours (urbanized areas). In one hand, 404 of these contours could be consider as real "metropolitan areas"; and in the other hand, there are 161,821 contours with less than 5,000 inhabitants, which could be identify as "villages". Finally, the paper shows that 44.5 % live in rural areas, 15.5 % in rurban spaces, 26.2 % in suburban areas and only 18.4 % in central areas.

  4. Interstellar Light Sails

    NASA Astrophysics Data System (ADS)

    Matloff, G. L.

    The light sail, which is pushed through space by momentum exchange from impacting and reflected photons, is the only suggested method of interstellar propulsion that has thus far been successfully tested in space. The solar photon sail, unfurled as close to the Sun as possible, offers the possibility of ~2,000-year duration voyages to Alpha Centauri using currently existing sail materials and departure from the present-day Sun. Improvements in sail material technology and departure from more luminous stars may greatly reduce interstellar transit time. During interstellar cruise, the sail could be wrapped around the habitat to provide cosmic ray shielding. The sail could be unfurled late in the flight to decelerate the spacecraft to planetary velocities. Collimated laser and maser beams, projected from power stations closer to the Sun than the starship, could overcome the limitations imposed by the inverse-square law and allow higher interstellar cruise velocities, if beam aim and collimation can be maintained over trillion-kilometer distances. This paper reviews progress on interstellar light sailing, discusses combination with other interstellar propulsion modes, and indicates some directions for future research.

  5. Concealing with Structured Light

    PubMed Central

    Sun, Jingbo; Zeng, Jinwei; Wang, Xi; Cartwright, Alexander N.; Litchinitser, Natalia M.

    2014-01-01

    While making objects less visible (or invisible) to a human eye or a radar has captured people's imagination for centuries, current attempts towards realization of this long-awaited functionality range from various stealth technologies to recently proposed cloaking devices. A majority of proposed approaches share a number of common deficiencies such as design complexity, polarization effects, bandwidth, losses and the physical size or shape requirement complicating their implementation especially at optical frequencies. Here we demonstrate an alternative way to conceal macroscopic objects by structuring light itself. In our approach, the incident light is transformed into an optical vortex with a dark core that can be used to conceal macroscopic objects. Once such a beam passed around the object it is transformed back into its initial Gaussian shape with minimum amplitude and phase distortions. Therefore, we propose to use that dark core of the vortex beam to conceal an object that is macroscopic yet small enough to fit the dark (negligibly low intensity) region of the beam. The proposed concealing approach is polarization independent, easy to fabricate, lossless, operates at wavelengths ranging from 560 to 700 nm, and can be used to hide macroscopic objects providing they are smaller than vortex core. PMID:24522638

  6. Light, including ultraviolet.

    PubMed

    Maverakis, Emanual; Miyamura, Yoshinori; Bowen, Michael P; Correa, Genevieve; Ono, Yoko; Goodarzi, Heidi

    2010-05-01

    Ultraviolet (UV) light is intricately linked to the functional status of the cutaneous immune system. In susceptible individuals, UV radiation can ignite pathogenic inflammatory pathways leading to allergy or autoimmunity. In others, this same UV radiation can be used as a phototherapy to suppress pathogenic cutaneous immune responses. These vastly different properties are a direct result of UV light's ability to ionize molecules in the skin and thereby chemically alter them. Sometimes these UV-induced chemical reactions are essential, the formation of pre-vitamin D(3) from 7-dehydrocholesterol, for example. In other instances they can be potentially detrimental. UV radiation can ionize a cell's DNA causing adjacent pyrimidine bases to chemically bond to each other. To prevent malignant transformation, a cell may respond to this UV-induced DNA damage by undergoing apoptosis. Although this pathway prevents skin cancer it also has the potential of inducing or exacerbating autoreactive immune responses by exposing the cell's nuclear antigens. Ultraviolet-induced chemical reactions can activate the immune system by a variety of other mechanisms as well. In response to UV irradiation keratinocytes secrete cytokines and chemokines, which activate and recruit leukocytes to the skin. In some individuals UV-induced chemical reactions can synthesize novel antigens resulting in a photoallergy. Alternatively, photosensitizing molecules can damage cells by initiating sunburn-like phototoxic reactions. Herein we review all types of UV-induced skin reactions, especially those involving the immune system. Published by Elsevier Ltd.

  7. Across light: through colour

    NASA Astrophysics Data System (ADS)

    Azevedo, Isabel; Richardson, Martin; Bernardo, Luis Miguel

    2012-03-01

    The speed at which our world is changing is reflected in the shifting way artistic images are created and produced. Holography can be used as a medium to express the perception of space with light and colour and to make the material and the immaterial experiments with optical and digital holography. This paper intends to be a reflection on the final product of that process surrounding a debate of ideas for new experimental methodologies applied to holographic images. Holography is a time-based medium and the irretrievable linear flow of time is responsible for a drama, unique to traditional cinematography. If the viewers move to left or right, they see glimpses of the next scene or the previous one perceived a second ago. This interaction of synthetic space arises questions such as: can we see, in "reality", two forms in the same space? Trying to answer this question, a series of works has been created. These concepts are embryonic to a series of digital art holograms and lenticulars technique's titled "Across Light: Through Colour". They required some technical research and comparison between effects from different camera types, using Canon IS3 and Sony HDR CX105.

  8. Light Echoes of Historic Transients

    NASA Astrophysics Data System (ADS)

    Rest, Armin; Sinnott, B.; Welch, D. L.; Prieto, J. L.; Bianco, F.

    2014-01-01

    Light echoes, light from a variable source scattered off dust, have been observed for over a century. The recent discovery of light echoes around centuries-old supernovae in the Milky Way and the Large Magellanic Cloud have allowed the spectroscopic characterization of these events, even without contemporaneous photometry and spectroscopy using modern instrumentation. Here we review the recent scientific advances using light echoes of ancient and historic transients, and focus on our latest work on SN 1987A's and Eta Carinae's light echoes.

  9. Low Light Level TV Techniques.

    PubMed

    Gildea, J

    1970-10-01

    As the science of low light level sensing becomes better understood, the demand for systems with this capability has increased considerably in recent years. Low light level television systems are part of these low light sensing devices in which interest has grown. Development of low light level TV systems has, in turn, stimulated technical advances in new tube types with improved performance, development of electronic techniques which enhance the over-all performance, and design techniques which make the system more versatile and adaptable. A general look at some of these developments and techniques gives insight into the versatility and adaptability of low light level TV.

  10. Shade Guide Lights: Technical Evaluation

    DTIC Science & Technology

    1988-12-01

    Vident Lumin Shade Light, ambient roomn li5ght, and the unit light. Selected shades were recorded and results were c nlzd This evaluation showed that...dentists and one dental laboratory technician on five natural teeth using the Efos Esthelite, Vident Lumin Shade Light, dental unit light (Ritter...tested: Efos Esthelite Unit Cost $300.00 Caulk/Dentsply P.O. Box 359 Milford, DE 19963 1-800-532-2S55 Vident Lumin Shade Light Unit Cost $395.00

  11. Light-Sensing in Roots

    PubMed Central

    Rabenold, Jessica J; Liscum, Emmanuel

    2007-01-01

    Light gradients in the soil have largely been overlooked in understanding plant responses to the environment. However, roots contain photoreceptors that may receive ambient light through the soil or piped light through the vascular cylinder. In recent experiments we demonstrated linkages between phototropin-1 photoreceptor production, root growth efficiency, and drought tolerance, suggesting that root plasticity in response to light signals contributes to the ecological niche of A. thaliana. However, the availability of light cues in natural soil environments is poorly understood, raising questions about the relevance of light-mediated root growth for fitness in nature. Additionally, photoreceptor expression is characterized by pleiotropy so unique functions cannot be clearly ascribed to root vs. shoot sensory mechanisms. These considerations show that challenges exist for resolving the contribution of light-sensing by roots to plant adaptation. We suggest that blue-light sensing in roots of A. thaliana provides a model system for addressing these challenges. By calibrating blue light gradients in soils of diverse A. thaliana habitats and comparing fitness of phot1 mutant and wild-type controls when grown in presence or absence of soil light cues, it should be possible to elucidate the ecological significance of light-mediated plasticity in roots. PMID:19704750

  12. High Temperature Induces Expression of Tobacco Transcription Factor NtMYC2a to Regulate Nicotine and JA Biosynthesis

    PubMed Central

    Yang, Liming; Li, Junying; Ji, Jianhui; Li, Ping; Yu, Liangliang; Abd_Allah, Elsayed F.; Luo, Yuming; Hu, Liwei; Hu, Xiangyang

    2016-01-01

    Environmental stress elevates the level of jasmonic acid (JA) and activates the biosynthesis of nicotine and related pyridine alkaloids in tobacco (Nicotiana tabacum L.) by up-regulating the expression of putrescine N-methyltransferase 1 (NtPMT1), which encodes a putrescine N-methyl transferase that catalyzes nicotine formation. The JA signal suppressor JASMONATE ZIM DOMAIN 1 (NtJAZ1) and its target protein, NtMYC2a, also regulate nicotine biosynthesis; however, how these proteins interact to regulate abiotic-induced nicotine biosynthesis is poorly understood. In this study, we found that high-temperature (HT) treatment activated transcription of NtMYC2a, which subsequently stimulated the transcription of genes associated with JA biosynthesis, including Lipoxygenase (LOX), Allene oxide synthase (AOS), Allene oxide cyclase (AOC), and 12-oxophytodienodate reductase (OPR). Overexpression of NtMYC2a increased nicotine biosynthesis by enhancing its binding to the promoter of NtPMT1. Overexpression of either NtJAZ1 or proteasome-resistant NtJAZ1ΔC suppressed nicotine production under normal conditions, but overexpression only of the former resulted in low levels of nicotine under HT treatment. These data suggest that HT induces NtMYC2a accumulation through increased transcription to activate nicotine synthesis; meanwhile, HT-induced NtMYC2a can activate JA synthesis to promote additional NtMYC2a activity by degrading NtJAZ1 at the post-transcriptional level. PMID:27833561

  13. The need for lighting education

    NASA Astrophysics Data System (ADS)

    Julian, Warren G.

    2002-05-01

    It is amazing that in a world now dominated by light - a world that is absolutely dependent upon light - that there is almost no lighting education. In a few countries of the world there exist tertiary level lighting programs but these can be counted on the fingers of two hands. Developments in lighting technology have produced a range of design tools that can lead to improved and energy-efficient lighting. However, most of this technology is 'harder' to use than traditional technology, emphasizing the need for not only improved lighting education but for its initiation. This paper discusses the need for education and uses the example of the University of Sydney program as a possible basis for others to use. It also examines how it is being delivered in Singapore.

  14. Focusing light through living tissue

    NASA Astrophysics Data System (ADS)

    Vellekoop, I. M.; Aegerter, C. M.

    2010-02-01

    Tissues such as skin, fat or cuticle are non-transparent because inhomogeneities in the tissue scatter light. We demonstrate experimentally that light can be focused through turbid layers of living tissue, in spite of scattering. Our method is based on the fact that coherent light forms an interference pattern, even after hundreds of scattering events. By spatially shaping the wavefront of the incident laser beam, this interference pattern was modified to make the scattered light converge to a focus. In contrast to earlier experiments, where light was focused through solid objects, we focused light through living pupae of Drosophila melanogaster. We discuss a dynamic wavefront shaping algorithm that follows changes due to microscopic movements of scattering particles in real time. We relate the performance of the algorithm to the measured timescale of the changes in the speckle pattern and analyze our experiment in the light of Laser Doppler flowmetry. Applications in particle tracking, imaging, and optical manipulation are discussed.

  15. Nanoparticles heat through light localization.

    PubMed

    Hogan, Nathaniel J; Urban, Alexander S; Ayala-Orozco, Ciceron; Pimpinelli, Alberto; Nordlander, Peter; Halas, Naomi J

    2014-08-13

    Aqueous solutions containing light-absorbing nanoparticles have recently been shown to produce steam at high efficiencies upon solar illumination, even when the temperature of the bulk fluid volume remains far below its boiling point. Here we show that this phenomenon is due to a collective effect mediated by multiple light scattering from the dispersed nanoparticles. Randomly positioned nanoparticles that both scatter and absorb light are able to concentrate light energy into mesoscale volumes near the illuminated surface of the liquid. The resulting light absorption creates intense localized heating and efficient vaporization of the surrounding liquid. Light trapping-induced localized heating provides the mechanism for low-temperature light-induced steam generation and is consistent with classical heat transfer.

  16. Evaluating the blue-light hazard from solid state lighting.

    PubMed

    Bullough, John D; Bierman, Andrew; Rea, Mark S

    2017-10-06

    New light sources including light-emitting diodes (LEDs) have elicited questions about retinal damage, including the blue-light hazard. Some organizations have recommended avoiding using LEDs with correlated color temperatures exceeding 3000 K, since they tend to produce greater short-wavelength energy. This article provides quantitative comparisons among light sources and use cases as they affect the blue-light hazard. The spectral radiant power characteristics of incandescent, fluorescent, LED and daylight sources were evaluated in terms of blue-light hazard using standard procedures for phakic, aphakic and pseudophakic eyes. Under most use cases, LEDs do not exhibit greater risk for the blue-light hazard than other sources (e.g., incandescent). Because they generally produce little to no ultraviolet energy, LEDs often present less risk to aphakic eyes. LEDs present no special concerns for the blue-light hazard over some other common sources in typical use cases because photophobic responses limit exposure to bright sources. Where photophobic responses might not occur (e.g., eye surgery patients or premature infants) or where individuals suppress these responses (e.g., stage actors), caution is necessary. Evidence remains inconsistent regarding the risk of human retinal damage from long-term exposures to light insufficient to reach acute blue-light hazard thresholds.

  17. Crystals in light.

    PubMed

    Kahr, Bart; Freudenthal, John; Gunn, Erica

    2010-05-18

    We have made images of crystals illuminated with polarized light for almost two decades. Early on, we abandoned photosensitive chemicals in favor of digital electrophotometry with all of the attendant advantages of quantitative intensity data. Accurate intensities are a boon because they can be used to analytically discriminate small effects in the presence of larger ones. The change in the form of our data followed camera technology that transformed picture taking the world over. Ironically, exposures in early photographs were presumed to correlate simply with light intensity, raising the hope that photography would replace sensorial interpretation with mechanical objectivity and supplant the art of visual photometry. This was only true in part. Quantitative imaging accurate enough to render the separation of crystalloptical quantities had to await the invention of the solid-state camera. Many pioneers in crystal optics were also major figures in the early history of photography. We draw out the union of optical crystallography and photography because the tree that connects the inventors of photography is a structure unmatched for organizing our work during the past 20 years, not to mention that silver halide crystallites used in chemical photography are among the most consequential "crystals in light", underscoring our title. We emphasize crystals that have acquired optical properties such as linear birefringence, linear dichroism, circular birefringence, and circular dichroism, during growth from solution. Other crystalloptical effects were discovered that are unique to curiously dissymmetric crystals containing embedded oscillators. In the aggregate, dyed crystals constitute a generalization of single crystal matrix isolation. Simple crystals provided kinetic stability to include guests such as proteins or molecules in excited states. Molecular lifetimes were extended for the preparation of laser gain media and for the study of the photodynamics of single

  18. Polarized Light Microscopy

    NASA Technical Reports Server (NTRS)

    Frandsen, Athela F.

    2016-01-01

    Polarized light microscopy (PLM) is a technique which employs the use of polarizing filters to obtain substantial optical property information about the material which is being observed. This information can be combined with other microscopy techniques to confirm or elucidate the identity of an unknown material, determine whether a particular contaminant is present (as with asbestos analysis), or to provide important information that can be used to refine a manufacturing or chemical process. PLM was the major microscopy technique in use for identification of materials for nearly a century since its introduction in 1834 by William Fox Talbot, as other techniques such as SEM (Scanning Electron Microscopy), FTIR (Fourier Transform Infrared spectroscopy), XPD (X-ray Powder Diffraction), and TEM (Transmission Electron Microscopy) had not yet been developed. Today, it is still the only technique approved by the Environmental Protection Agency (EPA) for asbestos analysis, and is often the technique first applied for identification of unknown materials. PLM uses different configurations in order to determine different material properties. With each configuration additional clues can be gathered, leading to a conclusion of material identity. With no polarizing filter, the microscope can be used just as a stereo optical microscope, and view qualities such as morphology, size, and number of phases. With a single polarizing filter (single polars), additional properties can be established, such as pleochroism, individual refractive indices, and dispersion staining. With two polarizing filters (crossed polars), even more can be deduced: isotropy vs. anisotropy, extinction angle, birefringence/degree of birefringence, sign of elongation, and anomalous polarization colors, among others. With the use of PLM many of these properties can be determined in a matter of seconds, even for those who are not highly trained. McCrone, a leader in the field of polarized light microscopy, often

  19. Fourth Light at Paranal!

    NASA Astrophysics Data System (ADS)

    2000-09-01

    VLT YEPUN Joins ANTU, KUEYEN and MELIPAL It was a historical moment last night (September 3 - 4, 2000) in the VLT Control Room at the Paranal Observatory , after nearly 15 years of hard work. Finally, four teams of astronomers and engineers were sitting at the terminals - and each team with access to an 8.2-m telescope! From now on, the powerful "Paranal Quartet" will be observing night after night, with a combined mirror surface of more than 210 m 2. And beginning next year, some of them will be linked to form part of the unique VLT Interferometer with unparalleled sensitivity and image sharpness. YEPUN "First Light" Early in the evening, the fourth 8.2-m Unit Telescope, YEPUN , was pointed to the sky for the first time and successfully achieved "First Light". Following a few technical exposures, a series of "first light" photos was made of several astronomical objects with the VLT Test Camera. This instrument was also used for the three previous "First Light" events for ANTU ( May 1998 ), KUEYEN ( March 1999 ) and MELIPAL ( January 2000 ). These images served to evaluate provisionally the performance of the new telescope, mainly in terms of mechanical and optical quality. The ESO staff were very pleased with the results and pronounced YEPUN fit for the subsequent commissioning phase. When the name YEPUN was first given to the fourth VLT Unit Telescope, it was supposed to mean "Sirius" in the Mapuche language. However, doubts have since arisen about this translation and a detailed investigation now indicates that the correct meaning is "Venus" (as the Evening Star). For a detailed explanation, please consult the essay On the Meaning of "YEPUN" , now available at the ESO website. The first images At 21:39 hrs local time (01:39 UT), YEPUN was turned to point in the direction of a dense Milky Way field, near the border between the constellations Sagitta (The Arrow) and Aquila (The Eagle). A guide star was acquired and the active optics system quickly optimized the

  20. Microchannel spatial light modulator

    NASA Technical Reports Server (NTRS)

    Warde, C.

    1981-01-01

    The Microchannel Spatial Light Modulator (MSLM), a versatile, highly sensitive, and optically addressed device being developed for real time optical information processing is discussed. The MSLM operates by converting an input optical image into a charge distribution at the surface of an electro-optic crystal. The charge distribution generates an electric field which modulates the refractive index of the crystal and thereby the phase or intensity of an image readout beam. Prototype devices employing 250 micron thick crystals exhibited a spatial resolution of 5 cycles/mm at 50% contrast, an exposure sensitivity of 2.2 nJ/cu cm and framing rates of 40 Hz with full modulation depth. The image processing operations that have been achieved using the internal processing mode of the MSLM include contrast reversal, contrast enhancement, edge enhancement, image addition and subtraction, analog and digital intensity thresholding, and binary level logic operations such as AND, OR, EXCLUSIVE OR, and NOR.

  1. Light Vision Color

    NASA Astrophysics Data System (ADS)

    Valberg, Arne

    2005-04-01

    Light Vision Color takes a well-balanced, interdisciplinary approach to our most important sensory system. The book successfully combines basics in vision sciences with recent developments from different areas such as neuroscience, biophysics, sensory psychology and philosophy. Originally published in 1998 this edition has been extensively revised and updated to include new chapters on clinical problems and eye diseases, low vision rehabilitation and the basic molecular biology and genetics of colour vision. Takes a broad interdisciplinary approach combining basics in vision sciences with the most recent developments in the area Includes an extensive list of technical terms and explanations to encourage student understanding Successfully brings together the most important areas of the subject in to one volume

  2. Nitride quantum light sources

    NASA Astrophysics Data System (ADS)

    Zhu, T.; Oliver, R. A.

    2016-02-01

    Prototype nitride quantum light sources, particularly single-photon emitters, have been successfully demonstrated, despite the challenges inherent in this complex materials system. The large band offsets available between different nitride alloys have allowed device operation at easily accessible temperatures. A wide range of approaches has been explored: not only self-assembled quantum dot growth but also lithographic methods for site-controlled nanostructure formation. All these approaches face common challenges, particularly strong background signals which contaminate the single-photon stream and excessive spectral diffusion of the quantum dot emission wavelength. If these challenges can be successfully overcome, then ongoing rapid progress in the conventional III-V semiconductors provides a roadmap for future progress in the nitrides.

  3. Advanced light source

    NASA Astrophysics Data System (ADS)

    Sah, R. C.

    1983-03-01

    The Advanced Light Source (ALS) is a new synchrotron radiation source which was proposed by Lawrence Berkeley Laboratory. The ALS will be a key component in a major new research facility, the National Center for Advanced Materials. The ALS will consist of an electron linear accelerator, a booster synchrotron, a 1.3-GeV electron storage ring, and a number of photon beam lines. Most of all photon beam lines will originate from wiggler and undulator magnets placed in the 12 long straight sections of the ALS. A very low electron beam emittance will provide photon beams of unsurpassed spectral brilliance from specially-designed undulators, and a high radiofrequency will produce very short pulse lengths.

  4. Light modulating device

    DOEpatents

    Rauh, R.D.; Goldner, R.B.

    1989-12-26

    In a device for transmitting light, means for controlling the transmissivity of the device, including a ceramic, reversibly electrochromic, crystalline element having a highly reflective state when injected with electrons and charge compensating ions and a highly transmissive state when the electrons and ions are removed, the crystalline element being characterized as having a reflectivity of at least 50% in the reflective state and not greater than 10% in the transmissive state, and means for modulating the crystalline element between the reflective and transmissive states by injecting ions into the crystalline element in response to an applied electrical current of a first polarity and removing the ions in response to an applied electrical current of a second polarity are disclosed. 1 fig.

  5. Cosmic fairy lights

    NASA Image and Video Library

    2014-04-21

    This sparkling jumble is Messier 5 — a globular cluster consisting of hundreds of thousands of stars bound together by their collective gravity. But Messier 5 is no normal globular cluster. At 13 billion years old it is incredibly old, dating back to close to the beginning of the Universe, which is some 13.8 billion years of age. It is also one of the biggest clusters known, and at only 24 500 light-years away, it is no wonder that Messier 5 is a popular site for astronomers to train their telescopes on. Messier 5 also presents a puzzle. Stars in globular clusters grow old and wise together. So Messier 5 should, by now, consist of old, low-mass red giants and other ancient stars. But it is actually teeming with young blue stars known as blue stragglers. These incongruous stars spring to life when stars collide, or rip material from one another.

  6. Hyperspectral light sheet microscopy

    NASA Astrophysics Data System (ADS)

    Jahr, Wiebke; Schmid, Benjamin; Schmied, Christopher; Fahrbach, Florian O.; Huisken, Jan

    2015-09-01

    To study the development and interactions of cells and tissues, multiple fluorescent markers need to be imaged efficiently in a single living organism. Instead of acquiring individual colours sequentially with filters, we created a platform based on line-scanning light sheet microscopy to record the entire spectrum for each pixel in a three-dimensional volume. We evaluated data sets with varying spectral sampling and determined the optimal channel width to be around 5 nm. With the help of these data sets, we show that our setup outperforms filter-based approaches with regard to image quality and discrimination of fluorophores. By spectral unmixing we resolved overlapping fluorophores with up to nanometre resolution and removed autofluorescence in zebrafish and fruit fly embryos.

  7. Directed light fabrication

    SciTech Connect

    Lewis, G.K.; Nemec, R.; Milewski, J.; Thoma, D.J.; Cremers, D.; Barbe, M.

    1994-09-01

    Directed Light Fabrication (DLF) is a rapid prototyping process being developed at Los Alamos National Laboratory to fabricate metal components. This is done by fusing gas delivered metal powder particles in the focal zone of a laser beam that is, programmed to move along or across the part cross section. Fully dense metal is built up a layer at a time to form the desired part represented by a 3 dimensional solid model from CAD software. Machine ``tool paths`` are created from the solid model that command the movement and processing parameters specific to the DLF process so that the part can be built one layer at a time. The result is a fully dense, near net shape metal part that solidifies under rapid solidification conditions.

  8. Intragroup and Intracluster Light

    NASA Astrophysics Data System (ADS)

    Mihos, J. Christopher

    2016-08-01

    The largest stellar halos in the universe are found in massive galaxy clusters, where interactions and mergers of galaxies, along with the cluster tidal field, all act to strip stars from their host galaxies and feed the diffuse intracluster light (ICL) and extended halos of brightest cluster galaxies (BCGs). Studies of the nearby Virgo Cluster reveal a variety of accretion signatures imprinted in the morphology and stellar populations of its ICL. While simulations suggest the ICL should grow with time, attempts to track this evolution across clusters spanning a range of mass and redshift have proved difficult due to a variety of observational and definitional issues. Meanwhile, studies of nearby galaxy groups reveal the earliest stages of ICL formation: the extremely diffuse tidal streams formed during interactions in the group environment.

  9. Directed light fabrication

    NASA Astrophysics Data System (ADS)

    Lewis, G. K.; Nemec, R.; Milewski, J.; Thoma, D. J.; Cremers, D.; Barbe, M.

    1994-09-01

    Directed Light Fabrication (DLF) is a rapid prototyping process being developed at Los Alamos National Laboratory to fabricate metal components. This is done by fusing gas delivered metal powder particles in the focal zone of a laser beam that is programmed to move along or across the part cross section. Fully dense metal is built up a layer at a time to form the desired part represented by a 3 dimensional solid model from CAD software. Machine 'tool paths' are created from the solid model that command the movement and processing parameters specific to the DLF process so that the part can be built one layer at a time. The result is a fully dense, near net shape metal part that solidifies under rapid solidification conditions.

  10. Light modulating device

    DOEpatents

    Rauh, R. David; Goldner, Ronald B.

    1989-01-01

    In a device for transmitting light, means for controlling the transmissivity of the device, including a ceramic, reversibly electrochromic, crystalline element having a highly reflective state when injected with electrons and charge compensating ions and a highly transmissive state when the electrons and ions are removed, the crystalline element being characterized as having a reflectivity of at least 50% in the reflective state and not greater than 10% in the transmissive state, and means for modulating the crystalline element between the reflective and transmissive states by injecting ions into the crystalline element in response to an applied electrical current of a first polarity and removing the ions in response to an applied electrical current of a second polarity.

  11. Synthesized light transients.

    PubMed

    Wirth, A; Hassan, M Th; Grguras, I; Gagnon, J; Moulet, A; Luu, T T; Pabst, S; Santra, R; Alahmed, Z A; Azzeer, A M; Yakovlev, V S; Pervak, V; Krausz, F; Goulielmakis, E

    2011-10-14

    Manipulation of electron dynamics calls for electromagnetic forces that can be confined to and controlled over sub-femtosecond time intervals. Tailored transients of light fields can provide these forces. We report on the generation of subcycle field transients spanning the infrared, visible, and ultraviolet frequency regimes with a 1.5-octave three-channel optical field synthesizer and their attosecond sampling. To demonstrate applicability, we field-ionized krypton atoms within a single wave crest and launched a valence-shell electron wavepacket with a well-defined initial phase. Half-cycle field excitation and attosecond probing revealed fine details of atomic-scale electron motion, such as the instantaneous rate of tunneling, the initial charge distribution of a valence-shell wavepacket, the attosecond dynamic shift (instantaneous ac Stark shift) of its energy levels, and its few-femtosecond coherent oscillations.

  12. Cost effective lighting

    SciTech Connect

    Morse, O.; Verderber, R.

    1987-07-01

    Long-life replacement lamps for the incandescent lamp have been evaluated with regard to their cost effectiveness. The replacements include the use of energy buttons that extend lamp life as well as an adaptive fluorescent circline lamp that will fit into existing incandescent lamp sockets. The initial, operating, and replacement costs for one million lumen-hours are determined for each lamp system. We find the most important lighting cost component is the operating cost. Using lamps that are less efficient or devices that cause lamps to operate less efficiently are not cost-effective. The adaptive fluorescent circline lamp, even at an initial cost of $15.00, is the most cost effective source of illumination compared to the incandescent lamp and lamp systems examined. 3 refs., 6 tabs.

  13. Residential lighting in Lithuania

    SciTech Connect

    Kazakevicius, Eduardas; Gadgil, Ashok; Vorsatz, Diana

    1998-09-01

    A wider use of compact fluorescent lamps (CFLs) offers a significant opportunity for Lithuania in reducing wasteful electricity consumption, and making progress towards retiring the Chernobyl-type Ignalina nuclear power reactors. The authors evaluate the conservation potential of compact fluorescent lamps for managing the residential electrical energy demand in Lithuania. The analysis is undertaken from the three-separate perspectives of (1) the national economy, (2) the consumers and (3) the utilities. In their analysis they use the most recent available data on Lithuanian residential lighting. The costs of conserved energy of 15 and 23 W CFLs range from $0.007 to 0.031 per kW-h depending on CFL price and assuming 4-hour daily lamp use. Replacing only the two most used 60 W incandescent lamps per household with CFLs would save 190 GW-h of electrical energy for Lithuania annually worth 12 million US dollars at the long run2048ginal cost. The authors compare the current residential lighting situation in Lithuania with that in Hungary and Poland, where introduction of CFLs has been much more successful. They then discuss factors that could explain the much higher CFL penetration in Hungary and Poland, barriers to immediate large-scale introduction of CFLs in Lithuania, and policy instruments that could be used for promoting the diffusion of CFLs in the residential sector of Lithuania. They conclude that future success of CFL penetration in Lithuania will depend on aggressive information and promotion efforts by at least the CFL manufacturers, and/or by any of the stakeholder institutions, (e.g., the state agencies responsible for energy and environment, electric utilities, international agencies, etc.).

  14. Inelastic Light Scattering Processes

    NASA Technical Reports Server (NTRS)

    Fouche, Daniel G.; Chang, Richard K.

    1973-01-01

    Five different inelastic light scattering processes will be denoted by, ordinary Raman scattering (ORS), resonance Raman scattering (RRS), off-resonance fluorescence (ORF), resonance fluorescence (RF), and broad fluorescence (BF). A distinction between fluorescence (including ORF and RF) and Raman scattering (including ORS and RRS) will be made in terms of the number of intermediate molecular states which contribute significantly to the scattered amplitude, and not in terms of excited state lifetimes or virtual versus real processes. The theory of these processes will be reviewed, including the effects of pressure, laser wavelength, and laser spectral distribution on the scattered intensity. The application of these processes to the remote sensing of atmospheric pollutants will be discussed briefly. It will be pointed out that the poor sensitivity of the ORS technique cannot be increased by going toward resonance without also compromising the advantages it has over the RF technique. Experimental results on inelastic light scattering from I(sub 2) vapor will be presented. As a single longitudinal mode 5145 A argon-ion laser line was tuned away from an I(sub 2) absorption line, the scattering was observed to change from RF to ORF. The basis, of the distinction is the different pressure dependence of the scattered intensity. Nearly three orders of magnitude enhancement of the scattered intensity was measured in going from ORF to RF. Forty-seven overtones were observed and their relative intensities measured. The ORF cross section of I(sub 2) compared to the ORS cross section of N2 was found to be 3 x 10(exp 6), with I(sub 2) at its room temperature vapor pressure.

  15. Adaptive filtering for white-light LED visible light communication

    NASA Astrophysics Data System (ADS)

    Hsu, Chin-Wei; Chen, Guan-Hong; Wei, Liang-Yu; Chow, Chi-Wai; Lu, I.-Cheng; Liu, Yen-Liang; Chen, Hsing-Yu; Yeh, Chien-Hung; Liu, Yang

    2017-01-01

    White-light phosphor-based light-emitting diode (LED) can be used to provide lighting and visible light communication (VLC) simultaneously. However, the long relaxation time of phosphor can reduce the modulation bandwidth and limit the VLC data rate. Recent VLC works focus on improving the LED modulation bandwidths. Here, we propose and demonstrate the use of adaptive Volterra filtering (AVF) to increase the data rate of a white-light LED VLC system. The detailed algorithm and implementation of the AVF for the VLC system have been discussed. Using our proposed electrical frontend circuit and the proposed AVF, a significant data rate enhancement to 700.68 Mbit/s is achieved after 1-m free-space transmission using a single white-light phosphor-based LED.

  16. Lattice QCD Calculation of Hadronic Light-by-Light Scattering.

    PubMed

    Green, Jeremy; Gryniuk, Oleksii; von Hippel, Georg; Meyer, Harvey B; Pascalutsa, Vladimir

    2015-11-27

    We perform a lattice QCD calculation of the hadronic light-by-light scattering amplitude in a broad kinematical range. At forward kinematics, the results are compared to a phenomenological analysis based on dispersive sum rules for light-by-light scattering. The size of the pion pole contribution is investigated for momenta of typical hadronic size. The presented numerical methods can be used to compute the hadronic light-by-light contribution to the anomalous magnetic moment of the muon. Our calculations are carried out in two-flavor QCD with the pion mass in the range of 270-450 MeV and contain so far only the diagrams with fully connected quark lines.

  17. Hadronic light-by-light scattering in muonium hyperfine splitting

    SciTech Connect

    Karshenboim, S. G.; Shelyuto, V. A.; Vainshtein, A. I.

    2008-09-15

    We consider an impact of hadronic light-by-light scattering on the muonium hyperfine structure. A shift of the hyperfine interval {delta}{nu}(Mu){sub HLBL} is calculated with the light-by-light scattering approximated by the exchange of pseudoscalar and pseudovector mesons. Constraints from the operator product expansion in QCD are used to fix parameters of the model similar to the one used earlier for the hadronic light-by-light scattering in calculations of the muon anomalous magnetic moment. The pseudovector exchange is dominant in the resulting shift, {delta}{nu}(Mu){sub HLBL}=-0.0065(10) Hz. Although the effect is tiny it is useful in understanding the level of hadronic uncertainties.

  18. Surface Roughness Effects on Light Propagation in Optical Light Pipes

    NASA Astrophysics Data System (ADS)

    Park, Youngjin

    Solid- and hollow-core light pipes are commonly employed to shape the intensity profile of high power lasers for applications in various technology industries such as the automobile, medical, and communications. There are several loss mechanisms present in solid-core glass and polymer light pipes, including absorption, bulk scattering in the material, surface scattering at the material-air interface, and Fresnel Loss at the material-air interface. Fresnel reflection and surface scattering losses typically dominate over other loss mechanisms in solid-core light pipes made of high quality optical materials. In order to analyze the losses in the light pipe, an approximate model is developed and tested using glass and polymer light pipes. The experiements in this thesis focus on analysis of the scattering loss in several optical light pipes configurations. From this analysis, the surface roughness parameters can be determined based on models and comparing with other measurements.

  19. Light extraction from organic light-emitting diodes for lighting applications by sand-blasting substrates.

    PubMed

    Chen, Shuming; Kwok, Hoi Sing

    2010-01-04

    Light extraction from organic light-emitting diodes (OLEDs) by scattering the light is one of the effective methods for large-area lighting applications. In this paper, we present a very simple and cost-effective method to rough the substrates and hence to scatter the light. By simply sand-blasting the edges and back-side surface of the glass substrates, a 20% improvement of forward efficiency has been demonstrated. Moreover, due to scattering effect, a constant color over all viewing angles and uniform light pattern with Lambertian distribution has been obtained. This simple and cost-effective method may be suitable for mass production of large-area OLEDs for lighting applications.

  20. Dynamic light intensity detection system of aerodrome assistance light

    NASA Astrophysics Data System (ADS)

    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.

  1. Traffic light to vehicle visible light communication channel characterization.

    PubMed

    Cui, Kaiyun; Chen, Gang; Xu, Zhengyuan; Roberts, Richard D

    2012-09-20

    Outdoor visible light communication (VLC) between an LED traffic light and an automobile has been proposed for intelligent transportation system development. An unobstructed line-of-sight (LOS) channel has to be guaranteed for this communication system. In this paper, an analytical LOS path loss model is proposed and validated by the measurement results. Commercial-off-the-shelf (COTS) LED traffic lights are characterized for use as transmitters and possible interference sources are studied, such as background solar radiation and artificial lighting. Accordingly, the performance of an outdoor VLC system is evaluated using different modulation schemes.

  2. Radioluminescent lighting for Alaskan runway lighting and marking

    SciTech Connect

    Jensen, G.A.; Leonard, L.E.

    1985-03-01

    Alaska and other far northern areas have special logistical, environmental, and economic problems that make radioluminescent (RL) lighting applications, especially in the area of airport lighting, an attractive alternative to electrical systems and flare pots. Tests and demonstrations of prototype systems conducted in Alaska over the past two years have proved the basic technological worth of RL airport lighting systems for civilian and military use. If regulatory issues and other factors identified during these tests can be favorably resolved and if the system and its components can be refined through production engineering, attractive applications for RL airfield lighting systems in Alaska and other remote locations could result.

  3. Flashing light in microalgae biotechnology.

    PubMed

    Abu-Ghosh, Said; Fixler, Dror; Dubinsky, Zvy; Iluz, David

    2016-03-01

    Flashing light can enhance photosynthesis and improve the quality and quantity of microalgal biomass, as it can increase the products of interest by magnitudes. Therefore, the integration of flashing light effect into microalgal cultivation systems should be considered. However, microalgae require a balanced mix of the light/dark cycle for higher growth rates, and respond to light intensity differently according to the pigments acquired or lost during the growth. This review highlights recently published results on flashing light effect on microalgae and its applications in biotechnology, as well as the recently developed bioreactors designed to fulfill this effect. It also discusses how this knowledge can be applied in selecting the optimal light frequencies and intensities with specific technical properties for increasing biomass production and/or the yield of the chemicals of interest by microalgae belonging to different genera.

  4. Scalar Potential Model of light

    NASA Astrophysics Data System (ADS)

    Hodge, John

    2008-04-01

    Some observations of light are inconsistent with a wave--like model. Other observations of light are inconsistent with a particle--like model. A model of light is proposed wherein Newton's and Democritus's speculations are combined with the cosmological scalar potential model (SPM). The SPM was tested by confrontation with observations of galaxy HI rotation curves (RCs), asymmetric RCs, redshift, discrete redshift, galaxy central mass, and central velocity dispersion; and with observations of the Pioneer Anomaly. The resulting model of light will be tested by numerical simulation of a photon behaving in a wave-like manner such as diffusion, interference, reflection, spectrography, and the Afshar experiment. Although the SPM light model requires more work, early results are beginning to emerge that suggest possible tests because a few predictions are inconsistent with both the current particle and wave models of light and that suggest a re-interpretation of the equations of quantum mechanics.

  5. Automatic Mechetronic Wheel Light Device

    DOEpatents

    Khan, Mohammed John Fitzgerald

    2004-09-14

    A wheel lighting device for illuminating a wheel of a vehicle to increase safety and enhance aesthetics. The device produces the appearance of a "ring of light" on a vehicle's wheels as the vehicle moves. The "ring of light" can automatically change in color and/or brightness according to a vehicle's speed, acceleration, jerk, selection of transmission gears, and/or engine speed. The device provides auxiliary indicator lights by producing light in conjunction with a vehicle's turn signals, hazard lights, alarm systems, and etc. The device comprises a combination of mechanical and electronic components and can be placed on the outer or inner surface of a wheel or made integral to a wheel or wheel cover. The device can be configured for all vehicle types, and is electrically powered by a vehicle's electrical system and/or battery.

  6. Slow light in flight imaging

    NASA Astrophysics Data System (ADS)

    Wilson, Kali; Little, Bethany; Gariepy, Genevieve; Henderson, Robert; Howell, John; Faccio, Daniele

    2017-02-01

    Slow-light media are of interest in the context of quantum computing and enhanced measurement of quantum effects, with particular emphasis on using slow light with single photons. We use light-in-flight imaging with a single-photon avalanche diode camera array to image in situ pulse propagation through a slow-light medium consisting of heated rubidium vapor. Light-in-flight imaging of slow-light propagation enables direct visualization of a series of physical effects, including simultaneous observation of spatial pulse compression and temporal pulse dispersion. Additionally, the single-photon nature of the camera allows for observation of the group velocity of single photons with measured single-photon fractional delays greater than 1 over 1 cm of propagation.

  7. Can dendritic cells see light?

    NASA Astrophysics Data System (ADS)

    Chen, Aaron C.-H.; Huang, Ying-Ying; Sharma, Sulbha K.; Hamblin, Michael R.

    2010-02-01

    There are many reports showing that low-level light/laser therapy (LLLT) can enhance wound healing, upregulate cell proliferation and has anti-apoptotic effects by activating intracellular protective genes. In the field of immune response study, it is not known with any certainty whether light/laser is proinflammatory or anti-inflammatory. Increasingly in recent times dendritic cells have been found to play an important role in inflammation and the immunological response. In this study, we try to look at the impact of low level near infrared light (810-nm) on murine bone-marrow derived dendritic cells. Changes in surface markers, including MHC II, CD80 and CD11c and the secretion of interleukins induced by light may provide additional evidence to reveal the mystery of how light affects the maturation of dendritic cells as well how these light-induced mature dendritic cells would affect the activation of adaptive immune response.

  8. The 7B-1 mutation in tomato (Solanum lycopersicum L.) confers a blue light-specific lower sensitivity to coronatine, a toxin produced by Pseudomonas syringae pv. tomato.

    PubMed

    Bergougnoux, Véronique; Hlavácková, Vladimíra; Plotzová, Renáta; Novák, Ondrej; Fellner, Martin

    2009-01-01

    The spontaneous mutant 7B-1 in tomato (Solanum lycopersicum=Lycopersicon esculentum) is a photoperiod-dependent male-sterile mutant previously reported as resistant to various abiotic stresses specifically under blue light. Since this finding improved the potential of 7B-1's use in breeding programmes, its susceptibility to stress induced by coronatine (COR), the phytotoxine produced by several Pseudomonas syringae strains, was assessed in this study. The 7B-1 mutant was found to be less sensitive than the corresponding wild type (WT) to COR treatment in a blue light-dependent manner. Treatment of WT and 7B-1 plants with COR induced a strong accumulation of salicylic acid (SA), jasmonic acid (JA), and abscisic acid (ABA) in hypocotyls. Interestingly, accumulation of ABA and SA in the 7B-1 mutant was distinctly greater than in WT, especially in blue light. Based on the cross-talk between SA- and JA-signalling pathways, expression analysis of NPR1 and COI1 genes, respectively involved in these pathways, was investigated in COR-stressed plants. The blue light-specific lower sensitivity of 7B-1 plants to COR was found to be associated with blue light-specific overexpression of the NPR1 gene. These data suggest that the SA-dependent NPR1-dependent pathway could be involved in the lower sensitivity of the 7B-1 mutant to COR. The role of anthocyanins and ABA accumulation during the response to COR is also discussed in the present study.

  9. Borescope Inspects With Visible Or Ultraviolet Light

    NASA Technical Reports Server (NTRS)

    Molina, Orlando G.

    1989-01-01

    Quartz optical fibers improve performance at ultraviolet wavelengths. Borescope used to inspect interior of small-diameter tubing by visible light and ultraviolet light. Employs quartz fibers to conduct ultraviolet light and visible light with high efficiency.

  10. Fast Light-Sheet Scanner

    NASA Technical Reports Server (NTRS)

    Hunter, William W., Jr.; Humphreys, William M., Jr.; Bartram, Scott M.

    1995-01-01

    Optomechanical apparatus maintains sheet of pulsed laser light perpendicular to reference axis while causing sheet of light to translate in oscillatory fashion along reference axis. Produces illumination for laser velocimeter in which submicrometer particles entrained in flow illuminated and imaged in parallel planes displaced from each other in rapid succession. Selected frequency of oscillation range upward from tens of hertz. Rotating window continuously shifts sheet of light laterally while maintaining sheet parallel to same plane.

  11. Formation of the Light Infantry.

    DTIC Science & Technology

    1986-03-21

    This essay examines the formation of the light infantry. Initially, the requirements for strategic deployment and deterrence are examined. The...background that led to the decision to form this type of division is discussed. The author reviews the historical precedence for light infantry force. Using...issues addressed consider the relationship of the light force to the Army’s New Manning System, COHORT. Other personnel matters examined include the

  12. Fast Light-Sheet Scanner

    NASA Technical Reports Server (NTRS)

    Hunter, William W., Jr.; Humphreys, William M., Jr.; Bartram, Scott M.

    1995-01-01

    Optomechanical apparatus maintains sheet of pulsed laser light perpendicular to reference axis while causing sheet of light to translate in oscillatory fashion along reference axis. Produces illumination for laser velocimeter in which submicrometer particles entrained in flow illuminated and imaged in parallel planes displaced from each other in rapid succession. Selected frequency of oscillation range upward from tens of hertz. Rotating window continuously shifts sheet of light laterally while maintaining sheet parallel to same plane.

  13. General lighting requirements for photosynthesis

    NASA Technical Reports Server (NTRS)

    Geiger, Donald R.

    1994-01-01

    This paper presents data that suggests some criteria for evaluating growth chamber and greenhouse lighting. A review of the general lighting requirements for photosynthesis reveals that four aspects of light are important: irradiance, quality, timing, and duration. Effective lighting should produce plants that perform according to the goals of the project. For example, for physiological studies the plants probably should exhibit morphology and physiology similar to that found in field-grown plants. For other projects the criteria will obviously be set according to the reason for raising the plants.

  14. Review of light scattering literature

    NASA Astrophysics Data System (ADS)

    Potts, Marie K.

    1994-06-01

    This report reviews the recent literature of static and dynamic light scattering of dilute and semidilute polymer solutions and gels, as obtained from the Chemical Abstracts Macromolecular Sections, and an electronic literature search. In general, this review has been confined to the interests of the Polymer Research Branch, specifically experimental light scattering studies of synthetic polymers in solution. In order to further limit the size of this review, light scattering for phase separation studies or particle size analysis have been excluded, as well as light scattering used strictly for size exclusion chromatography detection.

  15. Ophthalmic Light Sensitive Nanocarrier Systems

    PubMed Central

    Christie, Jennifer G.; Kompella, Uday B.

    2008-01-01

    The eye is afflicted by chronic vision debilitating neovascular disorders, such as age-related macular degeneration, proliferative diabetic retinopathy and corneal angiogenesis. Photodynamic therapy (PDT) is an innovative, evolving approach for treating neovascular diseases of the eye. PDT refers to the process of activating a light sensitive agent or carrier with non-thermal light to induce chemical reactions that ameliorate a pathological condition. Key components of PDT include a photosensitizer, a colloidal carrier or formulation and a light source. This article summarizes currently available clinical PDTs, desirable features of PDTs and photosensitizers, useful light sources for PDT and investigational nanosystems and colloidal carriers for PDT. PMID:18275910

  16. HIGHER FREQUENCY ULTRASONIC LIGHT MODULATORS.

    DTIC Science & Technology

    LIGHT ), (*MODULATORS, (*ULTRASONIC RADIATION, MODULATORS), OPTICAL COMMUNICATIONS, BANDWIDTH, TRANSDUCERS, HIGH FREQUENCY, VERY HIGH FREQUENCY, ATTENUATION, DATA PROCESSING, OPTICAL EQUIPMENT, ANALOG COMPUTERS, THEORY.

  17. Light pollution: responses and remedies

    NASA Astrophysics Data System (ADS)

    Mizon, Bob

    Light-pollution is the modern scourge of optical astronomy. More and more observing sites are being lost as the glare of city lighting blots out the night sky. Professional astronomical observatories are located far from cities, but amateur astronomers often do not have this luxury. This book considers the two available strategies open to astronomers - get rid of the light pollution by lobbying Authorities and Standards Organisations, and minimise its effects by using the correct instrumentation. The book contains an extensive detailed catalogue of deep-sky and other objects that - despite what one might believe - can be seen from variously light-polluted sites, for practical observers.

  18. Overexpression of OsMYC2 Results in the Up-Regulation of Early JA-Rresponsive Genes and Bacterial Blight Resistance in Rice.

    PubMed

    Uji, Yuya; Taniguchi, Shiduku; Tamaoki, Daisuke; Shishido, Hodaka; Akimitsu, Kazuya; Gomi, Kenji

    2016-09-01

    JASMONATE ZIM-domain (JAZ) proteins act as transcriptional repressors of jasmonic acid (JA) responses and play a crucial role in the regulation of host immunity in plants. Here, we report that OsMYC2, a JAZ-interacting transcription factor in rice (Oryza sativa L.), plays an important role in the resistance response against rice bacterial blight, which is one of the most serious diseases in rice, caused by Xanthomonas oryzae pv. oryzae (Xoo). The results showed that OsMYC2 interacted with some OsJAZ proteins in a JAZ-interacting domain (JID)-dependent manner. The up-regulation of OsMYC2 in response to JA was regulated by OsJAZ8. Transgenic rice plants overexpressing OsMYC2 exhibited a JA-hypersensitive phenotype and were more resistant to Xoo. A large-scale microarray analysis revealed that OsMYC2 up-regulated OsJAZ10 as well as many other defense-related genes. OsMYC2 selectively bound to the G-box-like motif of the OsJAZ10 promoter in vivo and regulated the expression of early JA-responsive genes, but not of late JA-responsive genes. The nuclear localization of OsMYC2 depended on a nuclear localization signal within JID. Overall, we conclude that OsMYC2 acts as a positive regulator of early JA signals in the JA-induced resistance against Xoo in rice.

  19. bHLH003, bHLH013 and bHLH017 Are New Targets of JAZ Repressors Negatively Regulating JA Responses

    PubMed Central

    Fonseca, Sandra; Fernández-Calvo, Patricia; Fernández, Guillermo M.; Díez-Díaz, Monica; Gimenez-Ibanez, Selena; López-Vidriero, Irene; Godoy, Marta; Fernández-Barbero, Gemma; Van Leene, Jelle; De Jaeger, Geert; Franco-Zorrilla, José Manuel; Solano, Roberto

    2014-01-01

    Cell reprogramming in response to jasmonates requires a tight control of transcription that is achieved by the activity of JA-related transcription factors (TFs). Among them, MYC2, MYC3 and MYC4 have been described as activators of JA responses. Here we characterized the function of bHLH003, bHLH013 and bHLH017 that conform a phylogenetic clade closely related to MYC2, MYC3 and MYC4. We found that these bHLHs form homo- and heterodimers and also interact with JAZ repressors in vitro and in vivo. Phenotypic analysis of JA-regulated processes, including root and rosette growth, anthocyanin accumulation, chlorophyll loss and resistance to Pseudomonas syringae, on mutants and overexpression lines, suggested that these bHLHs are repressors of JA responses. bHLH003, bHLH013 and bHLH017 are mainly nuclear proteins and bind DNA with similar specificity to that of MYC2, MYC3 and MYC4, but lack a conserved activation domain, suggesting that repression is achieved by competition for the same cis-regulatory elements. Moreover, expression of bHLH017 is induced by JA and depends on MYC2, suggesting a negative feed-back regulation of the activity of positive JA-related TFs. Our results suggest that the competition between positive and negative TFs determines the output of JA-dependent transcriptional activation. PMID:24465948

  20. DEMODULATION OF FREQUENCY OR SPACE MODULATED LIGHT.

    DTIC Science & Technology

    LIGHT , DEMODULATION), (*OPTICAL COMMUNICATIONS, FREQUENCY MODULATION), (*FREQUENCY MODULATION, LIGHT ), OPTICAL TRACKING, BEAMS(ELECTROMAGNETIC), DEFLECTION, MICROWAVE FREQUENCY, ELECTRON BEAMS, PHOTOCATHODES