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Sample records for upper-room uvc light

  1. Impact of Room Location on UV-C Irradiance and UV-C Dosage and Antimicrobial Effect Delivered by a Mobile UV-C Light Device.

    Science.gov (United States)

    Boyce, John M; Farrel, Patricia A; Towle, Dana; Fekieta, Renee; Aniskiewicz, Michael

    2016-06-01

    OBJECTIVE To evaluate ultraviolet C (UV-C) irradiance, UV-C dosage, and antimicrobial effect achieved by a mobile continuous UV-C device. DESIGN Prospective observational study. METHODS We used 6 UV light sensors to determine UV-C irradiance (W/cm2) and UV-C dosage (µWsec/cm2) at various distances from and orientations relative to the UV-C device during 5-minute and 15-minute cycles in an ICU room and a surgical ward room. In both rooms, stainless-steel disks inoculated with methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), and Clostridium difficile spores were placed next to sensors, and UV-C dosages and log10 reductions of target organisms achieved during 5-minute and 15-minute cycles were determined. Mean irradiance and dosage readings were compared using ANOVA. RESULTS Mean UV-C irradiance was nearly 1.0E-03 W/cm2 in direct sight at a distance of 1.3 m (4 ft) from the device but was 1.12E-05 W/cm2 on a horizontal surface in a shaded area 3.3 m (10 ft) from the device (P4 to 1-3 for MRSA, >4 to 1-2 for VRE and >4 to 0 log10 for C. difficile spores, depending on the distance from, and orientation relative to, the device with 5-minute and 15-minute cycles. CONCLUSION UV-C irradiance, dosage, and antimicrobial effect received from a mobile UV-C device varied substantially based on location in a room relative to the UV-C device. Infect Control Hosp Epidemiol 2016;37:667-672.

  2. Use Of Ultra Violet Light (UV-C) To Reduce Possible Microbial Potential In Cold Storage Rooms Loaded With Sweet Potatoes For Exportation

    International Nuclear Information System (INIS)

    Yassin, Sh.M.; El-Neshawy, S.M.; Aly, A.Z.; Abdel Kader, D.A.

    2012-01-01

    Irradiation with Ultraviolet-c (UV-C) light (254 nm) was applied on sweet potatoes (cv. Abees) as well as the major recovered organisms that are accounted as contaminants in either the internal atmosphere or on sweet potato tuber roots loaded in cold storage room set at 17 degree C and 65-70% RH for 3 months. The captured types of microorganisms from either the internal atmosphere of cold storage room or surfaces of sweet potato tuber roots were fungi, yeast and bacteria with the greatest percentage of fungi that recorded 90% and 70%, respectively. The major individuals of recovered fungi were Penicillium spp., Alternaria alternata, Rhizopus stolonifer, Aspergillus spp., Botrytis cinerea, and Fusarium sp. in descending order of their existence percentages. Upon exposure, the internal atmosphere to UV-C light for one, two and three hours inside cold storage room, a significant reduction of the total number of different types of organisms was obtained with the greatest effect for the three hour-exposure time. Exposure of sweet potatoes to UV-C light at three exposure times (1, 2 and 3 hr) and stored in cold rooms for one month caused a reduction of rot percentages upon natural infection conditions with a full reduction (0 %) when irradiated for 3 hr at the same conditions. Rot percentages were decreased as the exposure time increased. Fruit characteristics in terms of tuber root firmness, shrinking and blemishing of irradiated tuber roots were remarkably maintained than which of the non irradiated ones. UV-C light caused a significant increase in phenol contents in tuber root tissue, while a reverse effect in sugar content was detected; such effects were correlated increasingly or decreasingly with the increase of exposure time. The activity of peroxidase, polyphenoloxidase or poly phenylalanine ammonia lyase (PAL) enzymes in irradiated tuber root tissues were significantly enhanced as the exposure time increased

  3. Far-UVC light: A new tool to control the spread of airborne-mediated microbial diseases.

    Science.gov (United States)

    Welch, David; Buonanno, Manuela; Grilj, Veljko; Shuryak, Igor; Crickmore, Connor; Bigelow, Alan W; Randers-Pehrson, Gerhard; Johnson, Gary W; Brenner, David J

    2018-02-09

    Airborne-mediated microbial diseases such as influenza and tuberculosis represent major public health challenges. A direct approach to prevent airborne transmission is inactivation of airborne pathogens, and the airborne antimicrobial potential of UVC ultraviolet light has long been established; however, its widespread use in public settings is limited because conventional UVC light sources are both carcinogenic and cataractogenic. By contrast, we have previously shown that far-UVC light (207-222 nm) efficiently inactivates bacteria without harm to exposed mammalian skin. This is because, due to its strong absorbance in biological materials, far-UVC light cannot penetrate even the outer (non living) layers of human skin or eye; however, because bacteria and viruses are of micrometer or smaller dimensions, far-UVC can penetrate and inactivate them. We show for the first time that far-UVC efficiently inactivates airborne aerosolized viruses, with a very low dose of 2 mJ/cm 2 of 222-nm light inactivating >95% of aerosolized H1N1 influenza virus. Continuous very low dose-rate far-UVC light in indoor public locations is a promising, safe and inexpensive tool to reduce the spread of airborne-mediated microbial diseases.

  4. Upper-room ultraviolet light and negative air ionization to prevent tuberculosis transmission.

    Directory of Open Access Journals (Sweden)

    A Roderick Escombe

    2009-03-01

    Full Text Available Institutional tuberculosis (TB transmission is an important public health problem highlighted by the HIV/AIDS pandemic and the emergence of multidrug- and extensively drug-resistant TB. Effective TB infection control measures are urgently needed. We evaluated the efficacy of upper-room ultraviolet (UV lights and negative air ionization for preventing airborne TB transmission using a guinea pig air-sampling model to measure the TB infectiousness of ward air.For 535 consecutive days, exhaust air from an HIV-TB ward in Lima, Perú, was passed through three guinea pig air-sampling enclosures each housing approximately 150 guinea pigs, using a 2-d cycle. On UV-off days, ward air passed in parallel through a control animal enclosure and a similar enclosure containing negative ionizers. On UV-on days, UV lights and mixing fans were turned on in the ward, and a third animal enclosure alone received ward air. TB infection in guinea pigs was defined by monthly tuberculin skin tests. All guinea pigs underwent autopsy to test for TB disease, defined by characteristic autopsy changes or by the culture of Mycobacterium tuberculosis from organs. 35% (106/304 of guinea pigs in the control group developed TB infection, and this was reduced to 14% (43/303 by ionizers, and to 9.5% (29/307 by UV lights (both p < 0.0001 compared with the control group. TB disease was confirmed in 8.6% (26/304 of control group animals, and this was reduced to 4.3% (13/303 by ionizers, and to 3.6% (11/307 by UV lights (both p < 0.03 compared with the control group. Time-to-event analysis demonstrated that TB infection was prevented by ionizers (log-rank 27; p < 0.0001 and by UV lights (log-rank 46; p < 0.0001. Time-to-event analysis also demonstrated that TB disease was prevented by ionizers (log-rank 3.7; p = 0.055 and by UV lights (log-rank 5.4; p = 0.02. An alternative analysis using an airborne infection model demonstrated that ionizers prevented 60% of TB infection and 51% of TB

  5. Far-UVC light applications: sterilization of MRSA on a surface and inactivation of aerosolized influenza virus

    Science.gov (United States)

    Welch, David; Buonanno, Manuela; Shuryak, Igor; Randers-Pehrson, Gerhard; Spotnitz, Henry M.; Brenner, David J.

    2018-02-01

    Methicillin-resistant Staphylococcus aureus (MRSA) and influenza A virus are two of the major targets for new antimicrobial technologies. In contrast to conventional germicidal lamps emitting primarily at 254 nm, which are both carcinogenic and cataractogenic, recent work has shown the potential of far-UVC technology, mainly between 207 and 222 nm, to be an effective means of sterilization of pathogens without apparent harm to mammalian cells. This is because, due to its strong absorbance in biological materials, far-UVC light cannot penetrate even the outer (non living) layers of human skin or eye; however, because bacteria and viruses are of micrometer or smaller dimensions, far-UVC can penetrate and inactivate them. With this report, we present progress on in vitro tests to inactivate MRSA on a surface using far-UVC light from a laser delivered using an optical diffuser. Qualitative and quantitative results show that this means of far-UVC exposure is adequate to inactivate MRSA with a dose comparable to that which would be required using a conventional germicidal lamp. Also included is a report on progress on inactivation of aerosolized influenza A virus. A custom benchtop aerosol exposure chamber was constructed and used to determine the effectiveness of far- UVC. Results indicate that far-UVC efficiently inactivates airborne aerosolized viruses, with a very low dose of 2 mJ/cm2 of 222-nm light inactivating >95% of aerosolized H1N1 influenza virus. Together these studies help to further establish far-UVC technology as a promising, safe and inexpensive tool for sterilization in many environments.

  6. Time Effectiveness of Ultraviolet C Light (UVC Emitted by Light Emitting Diodes (LEDs in Reducing Stethoscope Contamination

    Directory of Open Access Journals (Sweden)

    Gabriele Messina

    2016-09-01

    Full Text Available Today it is well demonstrated that stethoscopes can be as contaminated as hands, which are a recognized source of Health-Care Associated Infections (HCAIs. Ultraviolet C (UVC light has proven disinfection capacity and the innovative UVC technology of Light Emitting Diode (LED shows several potential benefits. To verify whether the use of UVC LEDs is effective and reliable in stethoscope membrane disinfection after prolonged use, a pre-post intervention study was conducted. A total of 1668 five-minute cycles were performed on two UVC LEDs to simulate their use; thereafter, their disinfection capacity was tested on stethoscope membranes used on a previously auscultated volunteer. Then, a further 1249 cycles were run and finally the LEDs were tested to assess performance in reducing experimental contamination by Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli on the stethoscope membrane. Baseline volunteer contamination identified 104 Colony Forming Units (CFUs while treated Petri dishes had 12 and 15 CFUs (p < 0.001. Statistically significant differences (p < 0.001 were also found relating to the reduction of specific bacteria: in particular, after treatment no CFU were observed for S. aureus and E. coli. UVC LEDs demonstrated the capacity to maintain high levels of disinfection after more than 240 h of use and they were effective against common microorganisms that are causative agents of HCAIs.

  7. Time Effectiveness of Ultraviolet C Light (UVC) Emitted by Light Emitting Diodes (LEDs) in Reducing Stethoscope Contamination.

    Science.gov (United States)

    Messina, Gabriele; Fattorini, Mattia; Nante, Nicola; Rosadini, Daniele; Serafini, Andrea; Tani, Marco; Cevenini, Gabriele

    2016-09-23

    Today it is well demonstrated that stethoscopes can be as contaminated as hands, which are a recognized source of Health-Care Associated Infections (HCAIs). Ultraviolet C (UVC) light has proven disinfection capacity and the innovative UVC technology of Light Emitting Diode (LED) shows several potential benefits. To verify whether the use of UVC LEDs is effective and reliable in stethoscope membrane disinfection after prolonged use, a pre-post intervention study was conducted. A total of 1668 five-minute cycles were performed on two UVC LEDs to simulate their use; thereafter, their disinfection capacity was tested on stethoscope membranes used on a previously auscultated volunteer. Then, a further 1249 cycles were run and finally the LEDs were tested to assess performance in reducing experimental contamination by Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli on the stethoscope membrane. Baseline volunteer contamination identified 104 Colony Forming Units (CFUs) while treated Petri dishes had 12 and 15 CFUs (p < 0.001). Statistically significant differences (p < 0.001) were also found relating to the reduction of specific bacteria: in particular, after treatment no CFU were observed for S. aureus and E. coli. UVC LEDs demonstrated the capacity to maintain high levels of disinfection after more than 240 h of use and they were effective against common microorganisms that are causative agents of HCAIs.

  8. Dichotomy in response to indomethacin in uv-C and uv-B induced ultraviolet light inflammation

    International Nuclear Information System (INIS)

    Eaglstein, W.H.; Marsico, A.R.

    1975-01-01

    In subjects irradiated with both UV-C and UV-B ultraviolet light (UVL), 10 μg of intradermal indomethacin decreased the redness in all 13 of the UV-B irradiated areas but in only 2 of 13 of the UV-C irradiated areas. Higher doses of intradermal indomethacin (50 μg and 100 μg) decreased the redness produced by UV-C irradiation in 6 subjects. It is suggested that the failure of 10 μg of indomethacin to decrease the redness of the UV-C induced inflammation, while decreasing the redness in the UV-B induced inflammation, is consistent with the possibility that prostaglandins participate in UV-B but not UV-C induced inflammation

  9. Dose requirements for UVC disinfection of catheter biofilms

    DEFF Research Database (Denmark)

    Bak, Jimmy; Ladefoged, Søren D.; Tvede, Michael

    2009-01-01

    Bacterial biofilms on permanent catheters are the major sources of infection. Exposure to ultraviolet-C (UVC) light has been proposed as a method for disinfecting the inner surface of catheters. Specification of a UVC-based device for in vivo disinfection is based on the knowledge of the required...... doses to kill catheter biofilm. Given these doses and the power of available UVC light sources, calculation of the necessary treatment times is then possible. To determine the required doses, contaminated urinary catheters were used as test samples and UVC treated in vitro. Patient catheters (n = 67......) were collected and cut into segments of equal size and treated with various UVC doses. After treatment, the biofilm was removed by scraping and quantified by counting colony forming units. Percentage killing rates were determined by calculating ratios between UVC-treated samples and controls (no UVC...

  10. Effectiveness of UV-C light irradiation on disinfection of an eSOS(®) smart toilet evaluated in a temporary settlement in the Philippines.

    Science.gov (United States)

    Zakaria, Fiona; Harelimana, Bertin; Ćurko, Josip; van de Vossenberg, Jack; Garcia, Hector A; Hooijmans, Christine Maria; Brdjanovic, Damir

    2016-01-01

    Ultraviolet germicidal (short wavelength UV-C) light was studied as surface disinfectant in an Emergency Sanitation Operation System(®) smart toilet to aid to the work of manual cleaning. The UV-C light was installed and regulated as a self-cleaning feature of the toilet, which automatically irradiate after each toilet use. Two experimental phases were conducted i.e. preparatory phase consists of tests under laboratory conditions and field testing phase. The laboratory UV test indicated that irradiation for 10 min with medium-low intensity of 0.15-0.4 W/m(2) could achieve 6.5 log removal of Escherichia coli. Field testing of the toilet under real usage found that UV-C irradiation was capable to inactivate total coliform at toilet surfaces within 167-cm distance from the UV-C lamp (UV-C dose between 1.88 and 2.74 mW). UV-C irradiation is most effective with the support of effective manual cleaning. Application of UV-C for surface disinfection in emergency toilets could potentially reduce public health risks.

  11. Comparison of UV-C and Pulsed UV Light Treatments for Reduction of Salmonella, Listeria monocytogenes, and Enterohemorrhagic Escherichia coli on Eggs.

    Science.gov (United States)

    Holck, Askild L; Liland, Kristian H; Drømtorp, Signe M; Carlehög, Mats; McLEOD, Anette

    2018-01-01

    Ten percent of all strong-evidence foodborne outbreaks in the European Union are caused by Salmonella related to eggs and egg products. UV light may be used to decontaminate egg surfaces and reduce the risk of human salmonellosis infections. The efficiency of continuous UV-C (254 nm) and pulsed UV light for reducing the viability of Salmonella Enteritidis, Listeria monocytogenes, and enterohemorrhagic Escherichia coli on eggs was thoroughly compared. Bacterial cells were exposed to UV-C light at fluences from 0.05 to 3.0 J/cm 2 (10 mW/cm 2 , for 5 to 300 s) and pulsed UV light at fluences from 1.25 to 18.0 J/cm 2 , resulting in reductions ranging from 1.6 to 3.8 log, depending on conditions used. Using UV-C light, it was possible to achieve higher reductions at lower fluences compared with pulsed UV light. When Salmonella was stacked on a small area or shielded in feces, the pulsed UV light seemed to have a higher penetration capacity and gave higher bacterial reductions. Microscopy imaging and attempts to contaminate the interior of the eggs with Salmonella through the eggshell demonstrated that the integrity of the eggshell was maintained after UV light treatments. Only minor sensory changes were reported by panelists when the highest UV doses were used. UV-C and pulsed UV light treatments appear to be useful decontamination technologies that can be implemented in continuous processing.

  12. Improved Drinking Water Disinfection with UVC-LEDs for Escherichia Coli and Bacillus Subtilis Utilizing Quartz Tubes as Light Guide

    Directory of Open Access Journals (Sweden)

    Andrej Gross

    2015-08-01

    Full Text Available A new approach is investigated utilizing light guidance capabilities of optical pure quartz glass in order to maximize drinking water disinfection efficiency with UVC-light-emitting diodes (LEDs. Two experimental setups consisting of soda-lime AR® glass (VWR, Darmstadt, Germany or HSQ® 100 quartz glass (Heraeus, Wasserburg, Germany reactors were designed to compare disinfection rates with and without total reflection of UVC radiation along the reactor walls. Each reactor was filled with 9 mL bacteria samples containing either E. coli DSM (Deutsche Sammlung von Mikroorganismen 498 or B. subtilis DSM 402 strains (concentration 1–3 × 106 colony forming units (CFU/mL with and without additional mixing and irradiation periods of 10, 40, and 90 s. Disinfection rates were increased up to 0.95 log10 (E. coli and 0.75 log10 (B. subtilis by the light guide approach in stagnant samples. The same experiments with mixing of the samples resulted in an increased disinfection efficiency of 3.07 log10 (E. coli and 1.59 log10 (B. subtilis. Optical calculations determine that total reflection is achieved with the applied UVC-LED’s viewing angle of 15°. Furthermore measurements show that HSQ® 100 quartz has a transmittance of 92% at 280 nm UVC irradiation compared to the transmittance of soda-lime glass of 2% (1 mm wall thickness.

  13. UVC fluencies for preventative treatment of Pseudomonas aeruginosa contaminated polymer tubes

    DEFF Research Database (Denmark)

    Bak, Jimmy; Ladefoged, Søren D; Begovic, Tanja

    2010-01-01

    Exposing Pseudomonas aeruginosa biofilm grown on the inner surface of Teflon and silicone tubes to UVC light (265 nm) from light emitting diodes (LED) has previously been shown to substantially reduce biofilm growth. Smaller UVC fluencies were required to disinfect Teflon tubes compared to silicone...... tubes. Light propagation enhancement in tubes can be obtained if the refractive index of the intra-luminal saline solution is higher than that of the polymer. This condition is achieved by using Teflon tubes with a low refractive index (1.34) instead of the polymers with a high refractive index (1...... is demonstrated to be a preventative disinfection treatment on tubes made of Teflon, which enhances the UVC light propagation, and on tubes made of a softer material, ethylene vinyl acetate (EVA), which is suitable for catheters but much less suitable for UVC light propagation. Simulating an aseptic breach (~10...

  14. Post-harvest UVC irradiation effect on anthocyanin profile of grape berries

    International Nuclear Information System (INIS)

    Rosas, I. de; Ponce, M.; Gargantini, R.; Martinez, L.

    2010-01-01

    Anthocyanins are a class of phenolic compounds that contribute to the color of red grapes and have shown nutraceutical properties for human health. UVC light irradiation has been proved to increase phenolic compounds such as stilbenes, but its effect on anthocyanins has not been reported. The aim of this work was to identify the best treatment conditions of UVC light irradiation on post-harvest berries of Malbec (M), Cabernet Sauvignon (CS) and Tempranillo (T) for anthocyanin increments. Grape berries were irradiated with 240 W at 20 and 40 cm from the light source, for 30, 60 and 120 seconds. Both, irradiated and control grapes were stored on darkness at 20 C degree until anthocyanin extraction with methanol/ClH. HPLC analysis were performed and nine anthocyanins were quantified. UVC light irradiation modified the anthocyanin profile of the three cultivars. All the glucoside anthocyanins derivates and peonidin-acetyl-glucoside, as well as total anthocyanins were increased when CS berries were exposed to UVC for 120 s at 40 cm. This suggests that UVC stimulated the entire biosynthetic pathway. The anthocyanin content of the control berries was always higher than the treatments with UVC on M and T, making necessary to evaluate less rigorous conditions for these varieties. (authors)

  15. Photocatalytic removal of doxycycline from aqueous solution using ZnO nano-particles: a comparison between UV-C and visible light.

    Science.gov (United States)

    Pourmoslemi, Shabnam; Mohammadi, Ali; Kobarfard, Farzad; Amini, Mohsen

    2016-10-01

    Zinc oxide nano-particles were synthesized, characterized and used for photocatalytic degradation of doxycycline using UV-C and visible light. Effects of several operational factors including initial pH of antibiotic solution, initial antibiotic concentration and ZnO nano-particles loading amount were investigated. Comparing photocatalytic degradation and mineralization of doxycycline under UV-C and visible light showed successful application of the method under both light sources. However, reaction rate was higher under UV-C irradiation, which degraded doxycycline almost completely in 5 hours, and 68% mineralization was achieved. Synthesized ZnO nano-particles were successfully applied for photocatalytic degradation of doxycycline in a pharmaceutical wastewater sample. The process was fitted to the pseudo first order kinetic model with rate constants in the range of 6-22(×10 -3 ) mg L -1 min -1 with respect to initial concentration of doxycycline under UV-C irradiation. The Langmuir-Hinshelwood model was also employed for describing the photocatalytic reaction with surface reaction kinetic constant k c and equilibrium adsorption constant K LH values calculated as 0.12 mg L -1 min -1 and 2.2 L mg -1 , respectively. Degradation of doxycycline was followed by UV-visible spectroscopy and a validated stability indicating high-performance liquid chromatography method that was developed using stressed samples of doxycycline and could selectively determine doxycycline in the presence of its degradation products. Mass spectrometry was used for determining final degradation products.

  16. Preharvest methyl jasmonate and postharvest UVC treatments: increasing stilbenes in wine.

    Science.gov (United States)

    Fernández-Marín, María Isabel; Puertas, Belén; Guerrero, Raúl F; García-Parrilla, María Carmen; Cantos-Villar, Emma

    2014-03-01

    Stilbene-enriched wine is considered to be an interesting new food product with added value due to its potential health-promoting properties. Stilbene concentration in grape is highly variable and rather scarce. However, it can be increased by stress treatments. For this reason, numerous pre- and postharvest grape treatments, and some combinations of them, have been tested to maximize stilbene content in grapes. In the present manuscript, Syrah grapes were treated with (i) methyl jasmonate (MEJA), (ii) ultraviolet light (UVC), and (iii) methyl jasmonate and ultraviolet light (MEJA-UVC) and compared with untreated grapes. Afterward, winemaking was developed. Wine achieved by combination of both treatments (MEJA-UVC) contained significantly higher stilbene concentration (trans-resveratrol and piceatannol) than its respective control (2.5-fold). Wine quality was improved in color-related parameters (color intensity, L*, a*, b*, ΔE*, anthocyanins, and tannin). Moreover, MEJA-UVC wines obtained the highest score in sensorial analysis. To the best of our knowledge, this is the first time that pre- and postharvest treatments are combined to increase stilbenes in wine. The effect of treatment combination (methyl jasmonate and UVC light) on grape and wine was evaluated. Our results highlight the positive effect of the treatments in stilbene content, color parameters, and sensorial analysis. Moreover, added-value by-products were achieved. © 2014 Institute of Food Technologists®

  17. Electrophysiological and growing aspects of ultraviolet (UV-C) radiation action

    International Nuclear Information System (INIS)

    Karcz, W.

    1992-01-01

    Effects of UV-C (254 nm) radiation on electrical parameters and growth processes in plant cells were studied. It was found in Nitellopsis obtusa cells the UV-C radiation caused transient depolarization of plasmalemma and tonoplast and simultaneous increase in electric conductance. These effects were partly reversible and the degree of the recovery depended on the duration of the exposure, temperature of the medium and area of the irradiation. Exposure of Nitellopsis obtusa cells with large potential difference between vacuole and external medium (more negative than - 140 mV) brought about the generation of an action potential, whose shape depended on the duration of irradiation. In the cells pretreated with IAA in the dark or exposed to visible light, the UV-C irradiation not only abolished the hyper polarization induced by IAA or visible light, but caused a further depolarization. Similar effects of IAA and UV-C on membrane potential were demonstrated in cells of Zea mays L. coleoptile segments. The hyper polarized state created by visible light in Sagittaria leaf cells was also fully suppressed by the radiation. The growth experiments were based on elongation growth of Zea mays L. coleoptile segments and simultaneously measured changes of pH of the incubation medium. It was shown that for high doses of irradiation (1170, 3900, and 5850 J m -2 ) UV-C inhibited elongation growth, whereas at 195 J m -2 stimulation of growth was observed. The administration of IAA (10 -5 M) and FC (10 -6 M) to the incubation medium of coleoptile segments partially abolished the inhibitory effect of UV-C. The pH of the incubation medium showed that the exposure of the segments to UV-C caused inhibition H + -extrusion (or stimulation of H + uptake). The presence of IAA (10 -5 M) or FC (10 -6 M) in the incubation medium of irradiated coleoptile segments promoted H + -extrusion to a level comparable with that produced by IAA or FC in non-irradiated coleoptile segments. It is suggested

  18. Using an on-line UV-C apparatus to treat harvested fruit for controlling postharvest decay

    International Nuclear Information System (INIS)

    Wilson, C.L.; Upchurch, B.; El Ghaouth, A.; Stevens, C.; Khan, V.; Droby, S.; Chalutz, E.

    1997-01-01

    An apparatus was designed to deliver low-dose UV-C light to the surface of fruit on a processing line and tested for its control of postharvest decay. It consisted of a row of UV-C emitting lamps mounted on a frame above a conveyer belt that transported the fruit. The dosage of the UV-C light delivered to the fruit surface was regulated by varying the speed of the conveyor belt. Postharvest decay after 28 days storage of 'Empire' apples was reduced 52% relative to the untreated checks when the fruit were conveyed at 6.2 m · min -1 (1.38 kJ · m -2 dose) under the UV-C apparatus. Factors affecting the practical application of UV-C irradiation of fruit for controlling postharvest decay are discussed

  19. UVC fluencies for preventative treatment of pseudomonas aeruginosa contaminated polymer tubes

    DEFF Research Database (Denmark)

    Bak, Jimmy; Ladefoged, Søren D.; Begovic, Tanja

    2010-01-01

    .40-1.50) normally used for tubing in catheter production. Determining whether or not UVC light exposure can disinfect and maintain the intra-luminal number of colony forming units (CFUs) at an exceedingly low level and thus avoid the growth and establishment of biofilm is of interest. The use of UVC diodes...

  20. Inactivation of Nonpathogenic Escherichia coli, Escherichia coli O157:H7, Salmonella enterica Typhimurium, and Listeria monocytogenes in Ice Using a UVC Light-Emitting Diode.

    Science.gov (United States)

    Murashita, Suguru; Kawamura, Shuso; Koseki, Shigenobu

    2017-07-01

    Ice, widely used in the food industry, is a potential cause of food poisoning resulting from microbial contamination. Direct microbial inactivation of ice is necessary because microorganisms may have been present in the source water used to make it and/or may have been introduced due to poor hygiene during production or handling of the ice. Nonthermal and nondestructive microbial inactivation technologies are needed to control microorganisms in ice. We evaluated the applicability of a UVC light-emitting diode (UVC-LED) for microbial inactivation in ice. The effects of UV intensity and UV dose of the UVC-LED on Escherichia coli ATCC 25922 and a comparison of UVC-LED with a conventional UV lamp for effective bacterial inactivation in distilled water and ice cubes were investigated to evaluate the performance of the UVC-LED. Finally, we assessed the effects of the UVC-LED on pathogens such as E. coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes in ice cubes. The results indicated that UVC-LED effectiveness depended on the UV dose at all UV intensity conditions (0.084, 0.025, 0.013, 0.007, and 0.005 mW/cm 2 ) in ice and that UVC-LED could more efficiently inactivate E. coli ATCC 25922 in distilled water and ice than the UV lamp. At a UV dose of 2.64 mJ/cm 2 , E. coli in distilled water was decreased by 0.90 log CFU/mL (UV lamp) and by more than 7.0 log CFU/mL (UVC-LED). At 15.2 mJ/cm 2 , E. coli in ice was decreased by 3.18 log CFU/mL (UV lamp) and by 4.45 CFU/mL (UVC-LED). Furthermore, UVC-LED irradiation reduced the viable number of pathogens by 6 to 7 log cycles at 160 mJ/cm 2 , although the bactericidal effect was somewhat dependent on the type of bacteria. L. monocytogenes in ice was relatively more sensitive to UVC irradiation than were E. coli O157:H7 and Salmonella Typhimurium. These results demonstrate that UVC-LED irradiation could contribute to the safety of ice in the food industry.

  1. Application of 265-nm UVC LED Lighting to Sterilization of Typical Gram Negative and Positive Bacteria

    Science.gov (United States)

    Lee, Yong Wook; Yoon, Hyung Do; Park, Jae-Hyoun; Ryu, Uh-Chan

    2018-05-01

    UV LED lightings have been displacing conventional UV lamps due to their high efficiency, long lifetime, etc. A sterilizing lighting was prepared by assembling a UV LED module composed of 265-nm UVC LEDs and a silica lens array with a driver module comprised of a driver IC controlling pulse width modulation and constant current. The silica lens array was designed and fabricated to focus UV beam and simultaneously to give a uniform light distribution over specimens. Then pasteurizing effect of the lighting was analyzed for four kinds of bacteria and one yeast which are dangerous to people with low immunity. Sterilizing tests on these germs were carried out at the both exposure distances of 10 and 100 mm for various exposure durations up to 600 s.

  2. A control room lighting study

    International Nuclear Information System (INIS)

    Vaidya, V.V.; Iwasa-Madge, K.M.; Howard, B.; Willson, R.B.

    1984-01-01

    Operators at a Heavy Water Plant in Ontario, Canada complained about lighting-related difficulties in the control room. The Human Factors Engineering Unit was requested to perform a lighting survey and make recommendations to improve the control centre lighting conditions. This paper describes the control room, the operator tasks, the procedures used for the lighting survey, the findings, and the changes recommended

  3. Innovative UVC light (185 nm) and radio-frequency-plasma pretreatment of Nylon surfaces at atmospheric pressure and their implications in photocatalytic processes.

    Science.gov (United States)

    Mejía, M I; Marín, J M; Restrepo, G; Pulgarín, C; Mielczarski, E; Mielczarski, J; Stolitchnov, I; Kiwi, J

    2009-10-01

    Innovative pretreatment by UVC light (185 nm) and by radio-frequency (RF) plasma at atmospheric pressure to functionalize the Nylon surface, increasing its bondability toward TiO(2), is reported in this study. In the case of UVC light pretreatment in air, the molar absorption coefficient of O(2)/N(2) at 185 nm is very low and the air in the chamber absorbs very little light from the UVC source before reaching the Nylon sample. Nylon fabrics under RF plasma were also functionalized at atmospheric pressure because of the marked heating effect introduced in the Nylon by the RF plasma. This effect leads to intermolecular bond breaking and oxygenated surface groups in the topmost Nylon layers. Both pretreatments enhanced significantly the photocatalytic discoloration of the red-wine stain in Nylon-TiO(2) compared with samples without pretreatment. The UVC and RF methods in the absence of vacuum imply a considerable cost reduction to functionalize textile surfaces, suggesting a potential industrial application. Red-wine-stain discoloration under simulated sunlight was monitored quantitatively by diffuse-reflectance spectroscopy and by CO(2) evolution. X-ray photoelectron spectroscopy (XPS) was used to monitor the changes of the C, N, and S species on the Nylon topmost layers during the discoloration process. Significant changes in the XPS spectra of Ti 2p peaks were observed during discoloration of the wine spots. Wine stains attenuated the signal of the Ti 2p (458.4 eV) peak in the Nylon-TiO(2)-stained wine sample at time zero (from now on, the time before the discoloration process). Furthermore, a decrease of the wine-related O 1s signal at 529.7 eV and N 1s signal at 399.5 eV was observed during the discoloration process, indicating an efficient catalytic decomposition of the wine pigment on Nylon-TiO(2). X-ray diffraction detected the formation of anatase on the Nylon fibers. High-resolution transmission electron microscopy shows the formation of anatase particles

  4. Effect of millimeter waves on survival of UVC-exposed Escherichia coli

    International Nuclear Information System (INIS)

    Rojavin, M.A.; Ziskin, M.C.

    1995-01-01

    Bacterial cells of the strain Escherichia coli K12 were exposed to millimeter electromagnetic waves (mm waves) with and without additional exposure to ultraviolet light λ = 254 nm (UVC). The mm waves were produced by a medical microwave generator emitting a 4-GHz-wide band around a 61 GHz center frequency and delivering an irradiation of 1mW/cm 2 and a standard absorption rate (SAR) of 84 W/kg to the bacteria. Exposure to the mm waves alone for up to 30 minutes did not change the survival rate of bacteria. Exposure to mm waves followed by UVC irradiation also did not alter the number of surviving E. coli cells in comparison to UVC-treated controls. When mm waves were applied after the UVC exposure, a dose-dependent increase of up to 30% in the survival of E. coli was observed compared to UVC + sham-irradiated bacteria. Because sham controls and experimental samples were maintained under the same thermal conditions, the effect is not likely to be due to heating, although the possibility of nonuniform distribution of microwave heating in different layers of irradiated bacterial suspension cannot be ruled out. The mechanism for this effect appears to involve certain DNA repair systems that act as cellular targets for mm waves

  5. Efecto de la exposición a la luz ultravioleta uv-c en la viabilidad de especies de Eschericha coli y Salmonella typhimurium

    OpenAIRE

    Oviedo, Dumas; Rojas, Jesús María; Borda, Ricardo Alberto; Durango, Mónica María

    2013-01-01

    Introduction. The germicidal effect UV-C light has is regarded as an effective tool to inactivate and eliminate harmful contaminating agents, such as Escherichia coli and Salmonella typhimurium. Objective. evaluating the effectiveness of UV-C light for reducing Escherichia coli and Salmonella typhimorium populations from cultures that had the microorganisms, combining factors like concentration, time and distance. Methodology. A UV-C lamp, with a 254 nm and 8 ...

  6. Photodegradation of diphenylarsinic acid by UV-C light: Implication for its remediation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Anan; Teng, Ying [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Hu, Xuefeng [Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003 (China); Wu, Longhua; Huang, Yujuan [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Luo, Yongming, E-mail: ymluo@yic.ac.cn [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003 (China); Christie, Peter [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China)

    2016-05-05

    Highlights: • DPAA can be degraded into inorganic arsenics under the irradiation of UV-C light. • The photodegradation of DPAA mainly depended on its direct photolysis. • The {sup 1}O{sub 2} was generated, but had little effect on DPAA photolysis. • Cl{sup −} promoted the photolytic rate of DPAA, but NO{sub 3}{sup −}, NO{sub 2}{sup −} and HA inhibited it. - Abstract: Diphenylarsinic acid (DPAA) is a major contaminant in environments polluted by chemical weapons and abandoned after World Wars I and II and poses high risks to biota but remediation methods for this contaminant are rare. Here, the photodegradtion of DPAA was studied under high-pressure Hg lamp irradiation. DPAA was degraded completely into inorganic arsenic species in 30 min under UV-C irradiation. The photodegradation of DPAA depended mainly on its direct photolysis through excited-state DPAA. By contrast, the generation of {sup 1}O{sub 2} during the photodegradation of DPAA was confirmed by electron paramagnetic resonance (EPR) studies, but {sup 1}O{sub 2} had little effect on the photodegradation of DPAA. Phtotodegradation of DPAA was also studied in soil leachates and groundwater and the photolytic rate of DPAA was controlled by the total organic carbon (TOC) content in soil leachates and by the NO{sub 3}{sup −} concentration in groundwater. Finally, studies on the effects of common solutes on the photodegradation of DPAA show that Cl{sup −} can increase the photolytic rate of DPAA by prolonging the lifetime of excited-state DPAA. Moreover, NO{sub 3}{sup −}, NO{sub 2}{sup −}, and humic acid (HA) can decrease the photolytic rate of DPAA by suppressing the production of excited-state DPAA. This research shows the detailed mechanism of DPAA photodegradation and provides a new and effective method for DPAA decontamination.

  7. UVA, UVB and UVC Light Enhances the Biosynthesis of Phenolic Antioxidants in Fresh-Cut Carrot through a Synergistic Effect with Wounding

    Directory of Open Access Journals (Sweden)

    Bernadeth B. Surjadinata

    2017-04-01

    Full Text Available Previously, we found that phenolic content and antioxidant capacity (AOX in carrots increased with wounding intensity. It was also reported that UV radiation may trigger the phenylpropanoid metabolism in plant tissues. Here, we determined the combined effect of wounding intensity and UV radiation on phenolic compounds, AOX, and the phenylalanine ammonia-lyase (PAL activity of carrots. Accordingly, phenolic content, AOX, and PAL activity increased in cut carrots with the duration of UVC radiation, whereas whole carrots showed no increase. Carrot pies showed a higher increase compared to slices and shreds. Phenolics, AOX, and PAL activity also increased in cut carrots exposed to UVA or UVB. The major phenolics were chlorogenic acid and its isomers, ferulic acid, and isocoumarin. The type of UV radiation affected phenolic profiles. Chlorogenic acid was induced by all UV radiations but mostly by UVB and UVC, ferulic acid was induced by all UV lights to comparable levels, while isocoumarin and 4,5-diCQA was induced mainly by UVB and UVC compared to UVA. In general, total phenolics correlated linearly with AOX for all treatments. A reactive oxygen species (ROS mediated hypothetical mechanism explaining the synergistic effect of wounding and different UV radiation stresses on phenolics accumulation in plants is herein proposed.

  8. Using UVC Light-Emitting Diodes at Wavelengths of 266 to 279 Nanometers To Inactivate Foodborne Pathogens and Pasteurize Sliced Cheese

    Science.gov (United States)

    Kim, Soo-Ji; Kim, Do-Kyun

    2015-01-01

    UVC light is a widely used sterilization technology. However, UV lamps have several limitations, including low activity at refrigeration temperatures, a long warm-up time, and risk of mercury exposure. UV-type lamps only emit light at 254 nm, so as an alternative, UV light-emitting diodes (UV-LEDs) which can produce the desired wavelengths have been developed. In this study, we validated the inactivation efficacy of UV-LEDs by wavelength and compared the results to those of conventional UV lamps. Selective media inoculated with Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes were irradiated using UV-LEDs at 266, 270, 275, and 279 nm in the UVC spectrum at 0.1, 0.2, 0.5, and 0.7 mJ/cm2, respectively. The radiation intensity of the UV-LEDs was about 4 μW/cm2, and UV lamps were covered with polypropylene films to adjust the light intensity similar to those of UV-LEDs. In addition, we applied UV-LED to sliced cheese at doses of 1, 2, and 3 mJ/cm2. Our results showed that inactivation rates after UV-LED treatment were significantly different (P UV lamps at a similar intensity. On microbiological media, UV-LED treatments at 266 and 270 nm showed significantly different (P < 0.05) inactivation effects than other wavelength modules. For sliced cheeses, 4- to 5-log reductions occurred after treatment at 3 mJ/cm2 for all three pathogens, with negligible generation of injured cells. PMID:26386061

  9. Comparison of UVB and UVC irradiation disinfection efficacies on Pseudomonas Aeruginosa biofilm

    DEFF Research Database (Denmark)

    Argyraki, Aikaterini; Markvart, M.; Nielsen, Anne

    2016-01-01

    skin, soft tissue, lungs, kidney and urinary tract infections. Moreover, it can be found on and in medical equipment causing often cross infections in hospitals. The objective of this study was to test the efficiency, of two different light-based disinfection treatments, namely UVB and UVC irradiation......, on P. aeruginosa biofilms at different growth stages. In our experiments a new type of UV light emitting diodes (LEDs) were used to deliver UV irradiation on the biofilms, in the UVB (296nm) and UVC (266nm) region. The killing rate was studied as a function of dose for 24h grown biofilms. The dose......Disinfection routines are important in all clinical applications. The uprising problem of antibiotic resistance has driven major research efforts towards alternative disinfection approaches, involving light-based solutions. Pseudomonas aeruginosa (P. aeruginosa) is a common bacterium that can cause...

  10. Impact of shortwave ultraviolet (UV-C) radiation on the antioxidant activity of thyme (Thymus vulgaris L.).

    Science.gov (United States)

    Dogu-Baykut, Esra; Gunes, Gurbuz; Decker, Eric Andrew

    2014-08-15

    Thyme is a good source of antioxidant compounds but it can be contaminated by microorganisms. An experimental fluid bed ultraviolet (UV) reactor was designed for microbial decontamination of thyme samples and the effect of shortwave ultraviolet light (UV-C) radiation on antioxidant properties of thyme was studied. Samples were exposed to UV-C radiation for 16 or 64 min. UV-C treatment led to 1.04 and 1.38 log CFU/g reduction of total aerobic mesophilic bacteria (TAMB) counts. Hunter a(∗) value was the most sensitive colour parameter during UV-C treatment. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of extracts was not significantly affected by UV-C. Addition of thyme extracts at 0.15 and 0.3 μmol GAE/ml emulsion delayed the formation of lipid hydroperoxides and headspace hexanal in the 5.0%(wt) corn oil-in-water emulsion from 4 to 9 and 14 days, respectively. No significant changes in oxidation rates were observed between UV-C treated and untreated samples at same concentrations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Identification of barriers and research opportunities to improve the effective and efficient application of adjunct UVC surface disinfection in healthcare

    Science.gov (United States)

    Martinello, Richard A.; Miller, Shelly L.; Fabian, M. Patricia; Peccia, Jordan

    2018-02-01

    Healthcare associated infections (HAI) affect approximately 1 of every 25 hospitalized patients, lead to substantial morbidity and mortality, degrade patient experience and are costly. Risks for HAI are multifactorial and it is known that microbial contamination of the healthcare environment increases risk for HAI. Portable ultraviolet-C (UVC) surface disinfection as an adjunct to standard hospital disinfection has been shown to decrease both surface microbial contamination and HAI. However, there remain significant gaps in the understanding of the efficient and effective application of UVC in healthcare. Specific barriers identified are: 1) the variability in size, shape, and surface materials of hospital rooms as well as the presence of medical devices and furniture, which impacts the amount of UVC energy delivered to surfaces and its disinfection efficiency; 2) the significant resources needed to acquire and efficiently use UVC equipment and achieve the desired patient benefits- a particular challenge for complex healthcare facilities with limited operating margins; and 3) the lack of implementation guidance and industry standard methods for measuring the UVC output and antimicrobial effects from the multiple commercial UVC options available. An improved understanding of the efficient and effective use of UVC surface disinfection in healthcare and the implementation of standard device industry metrics may lead to increased use and decrease the burden of HAI.

  12. The Efficiency of UVC Radiation in the Inactivation of Listeria monocytogenes on Beef-Agar Food Models

    Directory of Open Access Journals (Sweden)

    Christian James

    2015-01-01

    Full Text Available The aim of this study is to evaluate the eff ect of meat content and surface smoothness on the deactivation of Listeria monocytogenes in beef-agar food models achieved by shortwave ultraviolet (UVC light. Food models with various meat contents were made using chopped beef slices and agar solution. Prepared models together with a Listeria selective agar (LSA plate and a slice of cooked beef were inoculated with L. monocytogenes and then exposed to UVC light. Population of Listeria reduced to below the level of detection on the LSA plates. As the content of beef in the beef-agar models increased, more L. monocytogenes cells survived. Survival was greatest on the treated cooked slice of beef. To bett er understand the effect of surface irregularities, a white light interferometer was used to analyse the surface smoothness of beef-agar media and LSA plates. No correlation was observed between the surface roughness of seven out of nine types of produced beef-agar media and the degree of inactivation resulting from UVC radiation at the given dose, whereas, less bacterial cells were killed as beef content of the food models increased. The findings of the current study show that the chemical composition of the treated sample also plays an important role in pathogen resistance and survival, meaning that two samples with similar surface irregularities but diff erent chemical composition might produce very diff erent inactivation results when exposed to UVC light.

  13. Postdischarge decontamination of MRSA, VRE, and Clostridium difficile isolation rooms using 2 commercially available automated ultraviolet-C-emitting devices.

    Science.gov (United States)

    Wong, Titus; Woznow, Tracey; Petrie, Mike; Murzello, Elena; Muniak, Allison; Kadora, Amin; Bryce, Elizabeth

    2016-04-01

    Two ultraviolet-C (UVC)-emitting devices were evaluated for effectiveness in reducing methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and Clostridium difficile (CD). Six surfaces in rooms previously occupied by patients with MRSA, VRE, or CD were cultured before and after cleaning and after UVC disinfection. In a parallel laboratory study, MRSA and VRE suspended in trypticase soy broth were inoculated onto stainless steel carriers in triplicate, placed in challenging room areas, subjected to UVC, and subcultured to detect growth. Sixty-one rooms and 360 surfaces were assessed. Before cleaning, MRSA was found in 34.4%, VRE was found in 29.5%, and CD was found in 31.8% of rooms. Cleaning reduced MRSA-, VRE-, and CD-contaminated rooms to 27.9%, 29.5%, and 22.7%, respectively (not statistically significant). UVC disinfection further reduced MRSA-, VRE-, and CD-contaminated rooms to 3.3% (P = .0003), 4.9% (P = .0003), and 0% (P = .0736), respectively. Surface colony counts (excluding floors) decreased from 88.0 to 19.6 colony forming units (CFU) (P < .0001) after manual cleaning; UVC disinfection further reduced it to 1.3 CFU (P = .0013). In a multivariable model of the carrier study, the odds of detecting growth in broth suspensions after UVC disinfection were 7 times higher with 1 machine (odds ratio, 6.96; 95% confidence interval, 3.79-13.4) for a given organism, surface, and concentration. UVC devices are effective adjuncts to manual cleaning but vary in their ability to disinfect high concentrations of organisms in the presence of protein. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  14. Melanin photosensitizes ultraviolet light (UVC) DNA damage in pigmented cells

    International Nuclear Information System (INIS)

    Huselton, C.A.; Hill, H.Z.

    1990-01-01

    Melanins, pigments of photoprotection and camouflage, are very photoreactive and can both absorb and emit active oxygen species. Nevertheless, black skinned individuals rarely develop skin cancer and melanin is assumed to act as a solar screen. Since DNA is the target for solar carcinogenesis, the effect of melanin on Ultraviolet (UV)-induced thymine lesions was examined in mouse melanoma and carcinoma cells that varied in melanin content. Cells prelabeled with 14C-dThd were irradiated with UVC; DNA was isolated, purified, degraded to bases by acid hydrolysis and analyzed by HPLC. Thymine dimers were detected in all of the extracts of irradiated cells. Melanotic and hypomelanotic but not mammary carcinoma cell DNA from irradiated cells contained hydrophilic thymine derivatives. The quantity of these damaged bases was a function of both the UVC dose and the cellular melanin content. One such derivative was identified by gas chromatography-mass spectroscopy as thymine glycol. The other appears to be derived from thymine glycol by further oxidation during acid hydrolysis of the DNA. The finding of oxidative DNA damage in melanin-containing cells suggests that melanin may be implicated in the etiology of caucasian skin cancer, particularly melanoma. Furthermore, the projected decrease in stratospheric ozone could impact in an unanticipated deleterious manner on dark-skinned individuals

  15. Using UVC Light-Emitting Diodes at Wavelengths of 266 to 279 Nanometers To Inactivate Foodborne Pathogens and Pasteurize Sliced Cheese.

    Science.gov (United States)

    Kim, Soo-Ji; Kim, Do-Kyun; Kang, Dong-Hyun

    2016-01-01

    UVC light is a widely used sterilization technology. However, UV lamps have several limitations, including low activity at refrigeration temperatures, a long warm-up time, and risk of mercury exposure. UV-type lamps only emit light at 254 nm, so as an alternative, UV light-emitting diodes (UV-LEDs) which can produce the desired wavelengths have been developed. In this study, we validated the inactivation efficacy of UV-LEDs by wavelength and compared the results to those of conventional UV lamps. Selective media inoculated with Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes were irradiated using UV-LEDs at 266, 270, 275, and 279 nm in the UVC spectrum at 0.1, 0.2, 0.5, and 0.7 mJ/cm(2), respectively. The radiation intensity of the UV-LEDs was about 4 μW/cm(2), and UV lamps were covered with polypropylene films to adjust the light intensity similar to those of UV-LEDs. In addition, we applied UV-LED to sliced cheese at doses of 1, 2, and 3 mJ/cm(2). Our results showed that inactivation rates after UV-LED treatment were significantly different (P < 0.05) from those of UV lamps at a similar intensity. On microbiological media, UV-LED treatments at 266 and 270 nm showed significantly different (P < 0.05) inactivation effects than other wavelength modules. For sliced cheeses, 4- to 5-log reductions occurred after treatment at 3 mJ/cm(2) for all three pathogens, with negligible generation of injured cells. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  16. Ultraviolet (UV)-reflective paint with ultraviolet germicidal irradiation (UVGI) improves decontamination of nosocomial bacteria on hospital room surfaces.

    Science.gov (United States)

    Jelden, Katelyn C; Gibbs, Shawn G; Smith, Philip W; Hewlett, Angela L; Iwen, Peter C; Schmid, Kendra K; Lowe, John J

    2017-06-01

    An ultraviolet germicidal irradiation (UVGI) generator (the TORCH, ClorDiSys Solutions, Inc.) was used to compare the disinfection of surface coupons (plastic from a bedrail, stainless steel, and chrome-plated light switch cover) in a hospital room with walls coated with ultraviolet (UV)-reflective paint (Lumacept) or standard paint. Each surface coupon was inoculated with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus faecalis (VRE), placed at 6 different sites within a hospital room coated with UV-reflective paint or standard paint, and treated by 10 min UVC exposure (UVC dose of 0-688 mJ/cm 2 between sites with standard paint and 0-553 mJ/cm 2 with UV-reflective paint) in 8 total trials. Aggregated MRSA concentrations on plastic bedrail surface coupons were reduced on average by 3.0 log 10 (1.8 log 10 Geometric Standard Deviation [GSD]) with standard paint and 4.3 log 10 (1.3 log 10 GSD) with UV-reflective paint (p = 0.0005) with no significant reduction differences between paints on stainless steel and chrome. Average VRE concentrations were reduced by ≥4.9 log 10 (surface types with UV-reflective paint and ≤4.1 log 10 (hospital bed from the UVGI generator, MRSA concentrations on average were reduced by 1.3 log 10 (1.7 log 10 GSD) with standard paint and 4.7 log 10 (1.3 log 10 GSD) with UV-reflective paint (p hospital room walls with UV-reflective paint enhanced UVGI disinfection of nosocomial bacteria on various surfaces compared to standard paint, particularly at a surface placement site indirectly exposed to UVC light.

  17. Potential In Vivo UVC Disinfection of Catheter Lumens: Estimation of the Doses Received by the Blood Flow Outside the Catheter Tip Hole

    DEFF Research Database (Denmark)

    Bak, Jimmy; Jørgensen, Thomas Martini; Helfmann, Jurgen

    2011-01-01

    hole for administration of drugs, bloods or nutrients into the bloodstream. Even if the UVC light is strongly attenuated during its propagation through the catheter tube a fraction of the UVC launched into the catheter will escape through the exit hole and irradiate the blood. We demonstrate......We have demonstrated that it is possible to launch UVC LED light into bacterial contaminated polymer tubes/catheters and disinfect the intraluminal space of these tubes. This can be achieved by UVC treatment of the catheters on a regular basis. Catheters are in the distal end equipped with an exit...... by calculations that very small effective doses are exposed to the blood (ca 10(-4) J m(-2) ). This dosage level is very low compared with UVC doses reported from other therapeutic applications. The very short residence time of the blood constituents in the irradiated volume in front of the exit hole is the main...

  18. The application of the light emitting diode in MR room lighting

    International Nuclear Information System (INIS)

    Cao Jun; Wang Chunhong

    2009-01-01

    Objective: To investigate the application of white light emitting diode (LED) in magnetic resonance room, in order to resolve the damageable problem of incandescent lights under the high magnetic field. Methods: The white LEDs and the incandescent lights were installed in MR room, the number of damaged lights was compared after 300 hours. Chi-square test was used for the statistical analysis. And the illuminance and 50 000 hours electricity consumption between LED and incandescent lights were calculated. Results: The number of damaged LED and incandescent lights was 2 and 32, respectively and there was a significant difference (χ 2 =48.813, P=0.000). The illuminance of the LED and incandescent lights was 155 lx and 100 lx at the 0.75 m horizontal level and the 50 000 hour's electricity consumption was 200 kW and 5000 kW, respectively. Conclusion: It is feasible and a great advantage to use the white LEDs in MR room lighting. (authors)

  19. Color, physicochemical parameters and antioxidant potential of whole grape juices subject to different UV-C radiation doses

    Directory of Open Access Journals (Sweden)

    Paôla de Castro Henrique

    2016-04-01

    Full Text Available ABSTRACT Knowing that moderate stress such as UV radiation can activate defense mechanisms in plants, the use of UV-C radiation appears as hypothesis of a promising technique that would help to stimulate and enhance beneficial compounds for health, through a clean and healthy technology. In this study, the possible induction of secondary metabolism, the increase in the content of phytochemical compounds and physicochemical changes through the use of UV-C radiation were evaluated on whole grape juices produced with Vitis labrusca grapes, cultivar Isabel Precoce. Grapes were harvested, sanitized, exposed to UV-C radiation at doses of 0, 2, 4 and 6 KJ m-2, and then the juices were prepared and packed into amber glass bottles at room temperature. Analyses were performed at 0, 30, 60, 90 and 120 days of storage. Based on results obtained and conditions in which the experiment was performed, UV-C treatment in grapes caused abiotic stress in the fruits, affecting color, titratable acidity, soluble solids/titratable acidity ratio, vitamin C and percentage of protection against oxidation. Application of UV-C did not change levels of phenolic compounds in fruit juices or the percentage of scavenging free radicals, pH and soluble solids.

  20. Listeria monocytogenes survival of UV-C radiation is enhanced by presence of sodium chloride, organic food material and by bacterial biofilm formation

    DEFF Research Database (Denmark)

    Bernbom, Nete; Vogel, Birte Fonnesbech; Gram, Lone

    2011-01-01

    The bactericidal effect on food processing surfaces of ceiling-mounted UV-C light (wavelength 254nm) was determined in a fish smoke house after the routine cleaning and disinfection procedure. The total aerobic counts were reduced during UV-C light exposure (48h) and the number of Listeria...... and that it, as all disinfecting procedures, is hampered by the presence of organic material....

  1. The use of shore wave ultraviolet radiation for disinfection in operating rooms

    International Nuclear Information System (INIS)

    Baanrud, H.; Moan, J.

    1999-01-01

    Over a number of years short wave ultraviolet radiation (UVC;200-280 nm) has been used to disinfect air and surfaces in operating rooms, patient rooms and laboratories, as well as air in ventilation ducts. Despite the well-documented effect of ultraviolet radiation on air quality, this technology has been relatively little used. One advantage of this method is that the UVC sources ensure a continuous reduction in the number of airborne microorganisms that are generated all the time. There are, however, some disadvantages with this method. Human exposure to ultraviolet C may cause keratoconjunctivitis and erythema and requires protection of the skin and the eyes of people exposed to levels above recommended exposure limits. However, by enclosing the UVC sources or by irradiation in the absence of human activity, human exposure is eliminated. These and other aspects concerning the use of short wave ultraviolet radiation as a disinfection agent in operating rooms are discussed in this article

  2. Inactivation of pathogenic bacteria inoculated onto a Bacto™ agar model surface using TiO2-UVC photocatalysis, UVC and chlorine treatments.

    Science.gov (United States)

    Yoo, S; Ghafoor, K; Kim, S; Sun, Y W; Kim, J U; Yang, K; Lee, D-U; Shahbaz, H M; Park, J

    2015-09-01

    The aim of this study was to study inactivation of different pathogenic bacteria on agar model surface using TiO2-UV photocatalysis (TUVP). A unified food surface model was simulated using Bacto(™) agar, a routinely used microbial medium. The foodborne pathogenic bacteria Escherichia coli K12 (as a surrogate for E. coli O157:H7), Salmonella Typhimurium, Staphylococcus aureus and Listeria monocytogenes were inoculated onto the agar surface, followed by investigation of TUVP-assisted inactivation and morphological changes in bacterial cells. The TUVP process showed higher bacterial inactivation, particularly for Gram-negative bacteria, than UVC alone and a control (dark reaction). A TUVP treatment of 17·2 mW cm(-2) (30% lower than the UVC light intensity) reduced the microbial load on the agar surface by 4·5-6·0 log CFU cm(-2). UVC treatment of 23·7 mW cm(-2) caused 3·0-5·3 log CFU cm(-2) reduction. The use of agar model surface is effective for investigation of bacterial disinfection and TUVP is a promising nonthermal technique. The results showing effects of photocatalysis and other treatments for inactivation of bacterial pathogens on model surface can be useful for applying such processes for disinfection of fruit, vegetables and other similar surfaces. © 2015 The Society for Applied Microbiology.

  3. Effect of UV-C irradiation on growth, sporulation and pathogenicity of cochliobolus sativus isolates

    International Nuclear Information System (INIS)

    Jawhar, M.; Arabi, M.I.E.

    1999-12-01

    More than 30 isolates of Cochliobolus sativus, the causal agent of common root rot disease; were collected from different regions of Syria. Seven of them were exposed to UV-C light for 40 or 60 h . at a dose rate of 2.52x10 -3 W/cm 2 . A significant increases in the mycelium growth and sporulation were detected (p<0.001). Within the studied range of UV wave length, these two parameters were increased upon increasing the period of exposure to UV-C light. The pathogenicity of four isolates was evaluated after 60 h. of UV irradiation. The response to UV irradiation varied among these isolates, and resulted in an increase in their virulence level (as assessed by evaluating disease severity on sub-crown internodes). Five barley genotypes possessing different levels of resistance to C. sativus were studied. Arabi Abiad was the most susceptible cultivar whereas, Taka 76 line was moderately susceptible. It is concluded that it is possible to implement the positive effect of low doses of UV-C in stimulating the sporulation of fungi, which are difficult to sporulate on artificial media. (author)

  4. The effect of UV-C exposure on larval survival of the dreissenid quagga mussel

    Science.gov (United States)

    Stewart-Malone, Alecia; Misamore, Michael; Wilmoth, Siri K.; Reyes, Alejandro; Wong, Wai Hing; Gross, Jackson

    2015-01-01

    The rapid spread of quagga mussels (Dreissena rostriformis bugensis) has lead to their invasion of Lake Mead, Nevada, the largest reservoir in North America and partially responsible for providing water to millions of people in the southwest. Current strategies for mitigating the growth and spread of quagga mussels primarily include physical and chemical means of removing adults within water treatment, delivery, and hydropower facilities. In the present study, germicidal ultraviolet light (UV-C) was used to target the larval stage of wild-caught quagga mussel. The lethal effect of UV-C was evaluated at four different doses, 0.0, 13.1, 26.2, and 79.6 mJ/cm2. Tested doses were determined based on results from preliminary trials. The results demonstrate that germicidal UV-C is effective in controlling the free-swimming life history stages of larval quagga mussels.

  5. The Effect of UV-C Exposure on Larval Survival of the Dreissenid Quagga Mussel.

    Science.gov (United States)

    Stewart-Malone, Alecia; Misamore, Michael; Wilmoth, Siri; Reyes, Alejandro; Wong, Wai Hing; Gross, Jackson

    2015-01-01

    The rapid spread of quagga mussels (Dreissena rostriformis bugensis) has lead to their invasion of Lake Mead, Nevada, the largest reservoir in North America and partially responsible for providing water to millions of people in the southwest. Current strategies for mitigating the growth and spread of quagga mussels primarily include physical and chemical means of removing adults within water treatment, delivery, and hydropower facilities. In the present study, germicidal ultraviolet light (UV-C) was used to target the larval stage of wild-caught quagga mussel. The lethal effect of UV-C was evaluated at four different doses, 0.0, 13.1, 26.2, and 79.6 mJ/cm2. Tested doses were determined based on results from preliminary trials. The results demonstrate that germicidal UV-C is effective in controlling the free-swimming life history stages of larval quagga mussels.

  6. Light and Mediaprojections in Patient Rooms

    DEFF Research Database (Denmark)

    Bonde, Esben Oxholm Skjødt; Nielsen, Stine Maria Louring; Hansen, Ellen Kathrine

    2018-01-01

    the specific needs of the patients and thereby provide higher patient satisfaction. Hereto, the main findings suggest that the control of the lighting needs to be less complicated, the different lighting settings needs to be better tailored to the actual needs, noise from the projector and light coming from......New media and lighting technology and new ways to connect and control it has potentials to improve the environment in hospitals with the goal of increasing patient satisfaction. How should such system be designed to do so and how can it be tested? In this paper it is investigated how a specific...... case, an interactive lighting and media system installed in a patient room, can be improved to support a greater experience of patient satisfaction. Through questionnaires given to 14 mothers who have just given birth and their husbands staying in an interactive patient room, the experience of staying...

  7. Disinfection of Biofilms in Tubes with Ultraviolet Light

    DEFF Research Database (Denmark)

    Bak, Jimmy; Begovic, Tanja

    2009-01-01

    Bacterial biofilms on long-term catheters are a major source of infection. We demonstrate here the potential of UVC light emitting diodes (LED) for disinfection purposes in catheter like tubes contaminated with biofilm. We show that UVC Light propagation is possible through teflon tubes using...... to a flow system and biofilms were produced during a three day period. Tubes in lengths of 10 cm (FEP teflon) were contaminated. Tubes for control and for UVC treatment were contaminated in parallel. The control and UVC treated tubes were both filled with a 20 % NaCl solution during the UVC treatment time...

  8. The Effect of UV-C Exposure on Larval Survival of the Dreissenid Quagga Mussel.

    Directory of Open Access Journals (Sweden)

    Alecia Stewart-Malone

    Full Text Available The rapid spread of quagga mussels (Dreissena rostriformis bugensis has lead to their invasion of Lake Mead, Nevada, the largest reservoir in North America and partially responsible for providing water to millions of people in the southwest. Current strategies for mitigating the growth and spread of quagga mussels primarily include physical and chemical means of removing adults within water treatment, delivery, and hydropower facilities. In the present study, germicidal ultraviolet light (UV-C was used to target the larval stage of wild-caught quagga mussel. The lethal effect of UV-C was evaluated at four different doses, 0.0, 13.1, 26.2, and 79.6 mJ/cm2. Tested doses were determined based on results from preliminary trials. The results demonstrate that germicidal UV-C is effective in controlling the free-swimming life history stages of larval quagga mussels.

  9. Reactions of the intracellular NADpool in the yeast S. cerevisiae after UV-C- or X-ray irradiation

    International Nuclear Information System (INIS)

    Winckler, K.; Herfurth, E.

    1988-01-01

    The reaction of the intracellular NADpool after irradiation of cells either with UV-C light or with X-rays was studied in four different strains of the yeast S. cerevisiae. We found neither in wildtype strains nor in radiation sensitive mutants remarkable changes in the NADpool within 2 h after irradiation. Preculture of cells in medium enriched with nicotinic acid, a precursor of NAD, influenced the intracellular NAD concentration only to a small extent in all strains, but enhanced the radiation resistance against UV-C significantly in one rad6 mutant strain. The uptake of NAD and NAC by all strains before and after irradiation with UV-C and X-ray was tested also. NAD generally is taken up by the cells to a very low extent before and after irradiation without irradiation-dose dependency. NAC is taken up by all strains before and after irradiation. Only the rad6 mutant exhibited an irradiation-dose dependent NAC-uptake after UV-C irradiation. (orig.)

  10. Kinetics of gene and chromosome mutations induced by UV-C in yeast Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Koltovaya, N.; Kokoreva, A.; Senchenko, D.; Shvaneva, N.; Zhuchkina, N.

    2017-01-01

    The systematic study of the kinetics of UV-induced gene and structural mutations in eukaryotic cells was carried out on the basis of model yeast S. cerevisiae. A variety of genetic assays (all types of base pair substitutions, frameshifts, forward mutations canl, chromosomal and plasmid rearrangements) in haploid strains were used. Yeast cells were treated by UV-C light of fluence of energy up to 200 J/m"2. The kinetics of the induced gene and structural mutations is represented by a linear-quadratic and exponential functions. The slope of curves in log-log plots was not constant, had the value 2-4 and depended on the interval of doses. It was suggested that it is the superposition and dynamics of different pathways form the mutagenic responses of eukaryotic cells to UV-C light that cause the high-order curves. [ru

  11. Determining coronal electron temperatures from observations with UVCS/SOHO

    Science.gov (United States)

    Fineschi, S.; Esser, R.; Habbal, S. R.; Karovska, M.; Romoli, M.; Strachan, L.; Kohl, J. L.; Huber, M. C. E.

    1995-01-01

    The electron temperature is a fundamental physical parameter of the coronal plasma. Currently, there are no direct measurements of this quantity in the extended corona. Observations with the Ultraviolet Coronagraph Spectrometer (UVCS) aboard the upcoming Solar and Heliospheric Observatory (SOHO) mission can provide the most direct determination of the electron kinetic temperature (or, more precisely, the electron velocity distribution along the line of sight). This measurement is based on the observation of the Thomson-scattered Lyman alpha (Ly-alpha) profile. This observation is made particularly challenging by the fact that the integrated intensity of the electron-scattered Ly-alpha line is about 10(exp 3) times fainter than that of the resonantly-scattered Ly-alpha component. In addition, the former is distributed across 50 A (FWHM), unlike the latter that is concentrated in 1 A. These facts impose stringent requirements on the stray-light rejection properties of the coronagraph/spectrometer, and in particular on the requirements for the grating. We make use of laboratory measurements of the UVCS Ly-alpha grating stray-light, and of simulated electron-scattered Ly-alpha profiles to estimate the expected confidence levels of electron temperature determination. Models of different structures typical of the corona (e.g., streamers, coronal holes) are used for this parameter study.

  12. UV-C Adaptation of Shigella: Morphological, Outer Membrane Proteins, Secreted Proteins, and Lipopolysaccharides Effects.

    Science.gov (United States)

    Chourabi, Kalthoum; Campoy, Susana; Rodriguez, Jesus A; Kloula, Salma; Landoulsi, Ahmed; Chatti, Abdelwaheb

    2017-11-01

    Water UV disinfection remains extremely important, particularly in developing countries where drinking and reclaimed crop irrigation water may spread devastating infectious diseases. Enteric bacterial pathogens, among which Shigella, are possible contaminants of drinking and bathing water and foods. To study the effect of UV light on Shigella, four strains were exposed to different doses in a laboratory-made irradiation device, given that the ultraviolet radiation degree of inactivation is directly related to the UV dose applied to water. Our results showed that the UV-C rays are effective against all the tested Shigella strains. However, UV-C doses appeared as determinant factors for Shigella eradication. On the other hand, Shigella-survived strains changed their outer membrane protein profiles, secreted proteins, and lipopolysaccharides. Also, as shown by electron microscopy transmission, morphological alterations were manifested by an internal cytoplasm disorganized and membrane envelope breaks. Taken together, the focus of interest of our study is to know the adaptive mechanism of UV-C resistance of Shigella strains.

  13. Effect of aging on UVC-induced apoptosis of rat splenocytes

    International Nuclear Information System (INIS)

    Radziszewska, E.; Piwocka, K.; Bielak-Zmijewska, A.; Sikora, E.; Skierski, J.

    2000-01-01

    UVC-induced apoptotic symptoms such as morphological changes, DNA fragmentation, Bcl-2 and Bax protein expression were examined in primary splenocyte cultures from young (3 months) and old (24 months) rats. The activities of AP-1 and CRE transcription factors in UVC-irradiated splenocytes were also assessed. At 24 h after UVC irradiation 40% of cells derived from young rats were found to be apoptotic, which was twice as much as in splenocytes from old rats. Apoptosis in cells from old rats did not give typical symptoms like a ''DNA ladder'' and Bcl-2 protein downregulation, in contrast to splenocytes from young rats. No AP-1 transcription factor activity was found in UVC-irradiated splenocytes from old animals and only a trace activity in splenocytes from young animals. This indicates that, UVC-induced apoptosis in rat splenocytes is practically AP-1 independent and that cells from old rats are less sensitive to UVC irradiation than splenocytes from young rats. (author)

  14. Effect of automated ultraviolet C-emitting device on decontamination of hospital rooms with and without real-time observation of terminal room disinfection.

    Science.gov (United States)

    Penno, Katie; Jandarov, Roman A; Sopirala, Madhuri M

    2017-11-01

    We studied the effectiveness of an ultraviolet C (UV-C) emitter in clinical settings and compared it with observed terminal disinfection. We cultured 22 hospital discharge rooms at a tertiary care academic medical center. Phase 1 (unobserved terminal disinfection) included cultures of 11 high-touch environmental surfaces (HTSs) after terminal room disinfection (AD) and after the use of a UV-C-emitting device (AUV). Phase 2 (observed terminal disinfection) included cultures before terminal room disinfection (BD), AD, and AUV. Zero-inflated Poisson regression compared mean colony forming units (CFU) between the groups. Two-sample proportion tests identified significance of the observed differences in proportions of thoroughly cleaned HTSs (CFU cleaning significantly reduced microbial burden and improved the thoroughness of terminal disinfection. We found no further benefit to UV-C use if standard terminal disinfection was observed. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  15. The effect of UV-B and UV-C radiation on Hibiscus leaves determined by ultraweak luminescence and fluorescence induction [chlorophyll fluorescence induction, ultraweak luminescence

    International Nuclear Information System (INIS)

    Panagopoulos, I.; Bornman, J.F.; Björn, L.O.

    1989-01-01

    The effects of UV-C (254 nm) and UV-B (280-320 nm) on chlorophyll fluorescence induction and ultraweak luminescence (UL) in detached leaves of Hibiscus rosa-sinensis L. were investigated. UL from leaves exposed to UV-B and UV-C radiation reached a maximum 72 h after irradiation. In both cases most of the light was of a wavelength over 600 nm. An increase in the percentage of long wavelength light with time was detected. UV radiation increased peroxidase activity, which also reached a maximum 72 h after irradiation. UV-B and UV-C both reduced variable chlorophyll fluorescence. No effect on the amount of chlorophyll or UV screening pigments was observed with the short-term irradiation used in this investigation. (author)

  16. Hyperspectral Surface Analysis for Ripeness Estimation and Quick UV-C Surface Treatments for Preservation of Bananas

    Science.gov (United States)

    Zhao, W.; Yang, Zh.; Chen, Zh.; Liu, J.; Wang, W. Ch.; Zheng, W. Yu.

    2016-05-01

    This study aimed to determine the ripeness of bananas using hyperspectral surface analysis and how a rapid UV-C (ultraviolet-C light) surface treatment could reduce decay. The surface of the banana fruit and its stages of maturity were studied using a hyperspectral imaging technique in the visible and near infrared (370-1000 nm) regions. The vselected color ratios from these spectral images were used for classifying the whole banana into immature, ripe, half-ripe and overripe stages. By using a BP neural network, models based on the wavelengths were developed to predict quality attributes. The mean discrimination rate was 98.17%. The surface of the fresh bananas was treated with UV-C at dosages from 15-55 μW/cm2. The visual qualities with or without UV-C treatment were compared using the image, the chromatic aberration test, the firmness test and the area of black spot on the banana skin. The results showed that high dosages of UV-C damaged the banana skin, while low dosages were more efficient at delaying changes in the relative brightness of the skin. The maximum UV-C treatment dose for satisfactory banana preservation was between 21 and 24 μW/cm2. These results could help to improve the visual quality of bananas and to classify their ripeness more easily.

  17. Comparison of UVB and UVC irradiation disinfection efficacies on Pseudomonas Aeruginosa (P. aeruginosa) biofilm

    Science.gov (United States)

    Argyraki, A.; Markvart, M.; Nielsen, Anne; Bjarnsholt, T.; Bjørndal, L.; Petersen, P. M.

    2016-04-01

    Disinfection routines are important in all clinical applications. The uprising problem of antibiotic resistance has driven major research efforts towards alternative disinfection approaches, involving light-based solutions. Pseudomonas aeruginosa (P. aeruginosa) is a common bacterium that can cause skin, soft tissue, lungs, kidney and urinary tract infections. Moreover, it can be found on and in medical equipment causing often cross infections in hospitals. The objective of this study was to test the efficiency, of two different light-based disinfection treatments, namely UVB and UVC irradiation, on P. aeruginosa biofilms at different growth stages. In our experiments a new type of UV light emitting diodes (LEDs) were used to deliver UV irradiation on the biofilms, in the UVB (296nm) and UVC (266nm) region. The killing rate was studied as a function of dose for 24h grown biofilms. The dose was ramped from 72J/m2 to 10000J/m2. It was shown that UVB irradiation was more effective than UVC irradiation in inactivating P. aeruginosa biofilms. No colony forming units (CFU) were observed for the UVB treated biofilms when the dose was 10000 J/m2 (CFU in control sample: 7.5 x 104). UVB irradiation at a dose of 20000J/m2 on mature biofilms (72h grown) resulted in a 3.9 log killing efficacy. The fact that the wavelength of 296nm exists in daylight and has such disinfection ability on biofilms gives new perspectives for applications within disinfection at hospitals.

  18. Effectiveness of UV-C light assisted by mild heat on Saccharomyces cerevisiae KE 162 inactivation in carrot-orange juice blend studied by flow cytometry and transmission electron microscopy.

    Science.gov (United States)

    García Carrillo, Mercedes; Ferrario, Mariana; Guerrero, Sandra

    2018-08-01

    The aim of this study was to analyze the effectiveness of UV-C light (0-10.6 kJ/m 2 ) assisted by mild heat treatment (50 °C) on the inactivation of Saccharomyces cerevisiae KE 162 in peptone water and fresh carrot-orange juice blend (pH: 3.8; 9.8°Brix; 707 NTU; absorption coefficient: 0.17 cm -1 ). Yeast induced damage by single UV-C and mild heat (H) and the combined treatment UV-C/H, was investigated by flow cytometry (FC) and transmission electron microscopy (TEM). When studying induced damage by FC, cells were labeled with fluorescein diacetate (FDA) and propidium iodide (PI) to monitor membrane integrity and esterase activity. UV-C/H provoked up to 4.7 log-reductions of S. cerevisiae; whereas, only 2.6-3.3 log-reductions were achieved by single UV-C and H treatments. FC revealed a shift with treatment time from cells with esterase activity and intact membrane to cells with permeabilized membrane. This shift was more noticeable in peptone water and UV-C/H treated juice. In the UV-C treated juice, double stained cells were detected, suggesting the possibility of being sub-lethally damaged, with compromised membrane but still metabolically active. TEM images of treated cells revealed severe damage, encompassing coagulated inner content, disorganized lumen and cell debris. FC and TEM provided additional information regarding degree and type of damage, complementing information revealed by the traditional plate count technique. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Comparison of UVC/S2O8 2- with UVC/H2O2 in terms of efficiency and cost for the removal of micropollutants from groundwater

    DEFF Research Database (Denmark)

    Antoniou, Maria; Andersen, Henrik Rasmus

    2015-01-01

    ' concentrations were tested with atrazine alone and in the micropollutants' mixture and it was decided to use 11.8mgL(-1) S2O8(2-) and 14.9mgL(-1) H2O2 for further testing since is closer to industrial applications and to minimize the residual oxidant concentration. Changes of the matrix composition......This study compared the UVC/S2O8(2-) system with the more commonly used AOP in water industry, UVC/H2O2, and examined whether the first one can be an economically feasible alternative technology. Atrazine and 4 volatile compounds (methyl tert-butyl ether, cis-dichlorethen, 1,4-dioxane and 1......-through reactor to simulate industrial applications. Initial experiments on the activation of oxidants with a LP lamp indicated that S2O8(2-) is photolysed about 2.3times faster than H2O2 and that the applied treatment times were not sufficient to utilize the majority of the oxidant. The effect of oxidants...

  20. Feasibility of touch-less control of operating room lights.

    Science.gov (United States)

    Hartmann, Florian; Schlaefer, Alexander

    2013-03-01

    Today's highly technical operating rooms lead to fairly complex surgical workflows where the surgeon has to interact with a number of devices, including the operating room light. Hence, ideally, the surgeon could direct the light without major disruption of his work. We studied whether a gesture tracking-based control of an automated operating room light is feasible. So far, there has been little research on control approaches for operating lights. We have implemented an exemplary setup to mimic an automated light controlled by a gesture tracking system. The setup includes a articulated arm to position the light source and an off-the-shelf RGBD camera to detect the user interaction. We assessed the tracking performance using a robot-mounted hand phantom and ran a number of tests with 18 volunteers to evaluate the potential of touch-less light control. All test persons were comfortable with using the gesture-based system and quickly learned how to move a light spot on flat surface. The hand tracking error is direction-dependent and in the range of several centimeters, with a standard deviation of less than 1 mm and up to 3.5 mm orthogonal and parallel to the finger orientation, respectively. However, the subjects had no problems following even more complex paths with a width of less than 10 cm. The average speed was 0.15 m/s, and even initially slow subjects improved over time. Gestures to initiate control can be performed in approximately 2 s. Two-thirds of the subjects considered gesture control to be simple, and a majority considered it to be rather efficient. Implementation of an automated operating room light and touch-less control using an RGBD camera for gesture tracking is feasible. The remaining tracking error does not affect smooth control, and the use of the system is intuitive even for inexperienced users.

  1. Covalent bindings in proteins following UV-C irradiation

    International Nuclear Information System (INIS)

    Diezel, W.; Meffert, H.; Soennichsen, N.; Reinicke, C.

    1980-01-01

    Following a UV-C irradiation of catalase cross-linked catalase subunits could be detected by sodium dodecylsulfate gel electrophoresis. The subunits of aldolase were not cross-linked. The origin of covalent bindings in the catalase molecule is suggested to be effected by a free radical chain reaction induced by the heme component of catalase after UV-C irradiation. (author)

  2. Age-related variation in the DNA-repair synthesis after UV-C irradiation in unstimulated lymphocytes of healthy blood donors

    International Nuclear Information System (INIS)

    Kovacs, E.; Weber, W.; Mueller, H.

    1984-01-01

    UV-C light-induced DNA-repair synthesis was studied in unstimulated lymphocytes of 51 healthy blood donors aged between 17 and 74 years. The evaluation included (1) the spontaneous DNA-synthesis in unirradiated lymphocytes with and without hydroxyurea, (2) the DNA-repair synthesis in lymphocytes irradiated with UV-light. The interindividual variation was significantly higher than the methodological variation ascertained in 24 persons in whom 2 determinations were carried out. In blood donors aged between 17 and 39 years, the spontaneous DNA synthesis, both with and without hydroxyurea, was significantly lower than in older individuals. The DNA-repair synthesis was dependent on the dose of UV-C light between 2 and 16 J/m 2 . There were no significant differences in DNA-repair synthesis in the age range 17-74 years. The variations in rate of DNA-repair synthesis were wider in older (44-74 years), than in younger individuals. (orig.)

  3. Patients’ Experience of Winter Depression and Light Room Treatment

    Directory of Open Access Journals (Sweden)

    Cecilia Rastad

    2017-01-01

    Full Text Available Background. There is a need for more knowledge on the effects of light room treatment in patients with seasonal affective disorder and to explore patients’ subjective experience of the disease and the treatment. Methods. This was a descriptive and explorative study applying qualitative content analysis. A purposeful sample of 18 psychiatric outpatients with a major depressive disorder with a seasonal pattern and a pretreatment score ≥12 on the 9-item Montgomery-Åsberg Depression self-rating scale was included (10 women and 8 men, aged 24–65 years. All patients had completed light room treatment (≥7/10 consecutive weekdays. Data was collected two weeks after treatment using a semistructured interview guide. Results. Patients described a clear seasonal pattern and a profound struggle to adapt to seasonal changes during the winter, including deterioration in sleep, daily rhythms, energy level, mood, activity, and cognitive functioning. Everyday life was affected with reduced work capacity, social withdrawal, and disturbed relations with family and friends. The light room treatment resulted in a radical and rapid improvement in all the major symptoms with only mild and transient side effects. Discussion. The results indicate that light room treatment is essential for some patients’ ability to cope with seasonal affective disorder.

  4. Effects of UV-C Light Exposure and Refrigeration on Phenolic and Antioxidant Profiles of Subtropical Fruits (Litchi, Longan, and Rambutan in Different Fruit Forms

    Directory of Open Access Journals (Sweden)

    Peilong Li

    2017-01-01

    Full Text Available The objectives of this study were to investigate how UV-C irradiation and refrigeration affect shelf-life and antioxidant level of litchi, longan, and rambutan. Three forms (whole, dehulled, and destoned of fresh fruits were treated by refrigeration and UV-C irradiations. After processing, deterioration rate, phenolics compounds, and antioxidant capacity were quantified. The deterioration rate was recorded as decay index. The results showed that both refrigeration and UV-C exposure extended the shelf-life of the fruits. The refrigeration enriched antioxidant levels of litchi but caused nutritional degradation in longan and rambutan; UV-C radiation enriched litchi antioxidant contents but was related to reduction of antioxidant capacity in longan and rambutan. Removing hulls and stones was associated with the decrease of antioxidants in litchi. The effects on antioxidant levels varied from fruit to fruit, resulting from hormesis phenomenon. The change of phytochemical levels was hypothesized as an accumulative process. The effects of fruit forms were not consistent in different fruits, which could be multifactorially influenced.

  5. Short UV-C Treatment Prevents Browning and Extends the Shelf-Life of Fresh-Cut Carambola

    Directory of Open Access Journals (Sweden)

    Carlota Moreno

    2017-01-01

    Full Text Available In this work, we selected a short UV-C treatment for fresh-cut carambola and assessed its efficacy in supplementing the benefits of low temperature storage. UV-C treated (6.0, 10.0, and 12.5 kJ m−2 carambola slices showed reduced deterioration compared to control fruit. Treatment with a dose of 12.5 kJ m−2 UV-C was more effective in maintaining quality and was selected for subsequent experiments evaluating the combination of UV-C and refrigeration on fruit storability and physical, chemical, and microbiological properties. Short UV-C exposure reduced weight loss and electrolyte leakage. UV-C treated carambola slices presented higher phenolic antioxidants than control after 21 d at 4°C and showed no alterations in soluble solids or titratable acidity. UV-C exposure also reduced the counts of molds, yeast, and aerobic mesophilic bacteria. UV-C treated fruit showed a fresh-like appearance even after 21 d as opposed to control carambola which presented spoilage and extensive browning symptoms. The reduction of fruit browning in UV-C treated fruit was not due to reduction in phenylalanine-ammonia lyase (PAL and/or peroxidase (POD, but rather through polyphenol oxidase (PPO inhibition and improved maintenance of tissue integrity.

  6. Preliminary Results from Coordinated UVCS-CDS-Ulysses Observations

    Science.gov (United States)

    Parenti, S.; Bromage, B. J.; Poletto, G.; Suess, S. T.; Raymond, J. C.; Noci, G.; Bromage, G. E.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    The June 2000 quadrature between the Sun, Earth, and Ulysses took place with Ulysses at a distance of 3.35 AU from the Sun and at heliocentric latitude 58.2 deg south, in the southeast quadrant. This provided an opportunity to observe the corona close to the Sun with Coronal Diagnostic Spectrometer (CDS) and Ultraviolet Coronograph Spectrometer (UVCS) and, subsequently, to sample the same plasma when it reached Ulysses. Here we focus on simultaneous observations of UVCS and CDS made on June 12, 13, 16 and 17. The UVCS data were acquired at heliocentric altitudes ranging from 1.6 to 2.2 solar radii, using different grating positions, in order to get a wide wavelength range. CDS data consisted of Normal Incidence Spectrometer (NIS) full wavelength rasters of 120" x 150" centered at altitudes up to 1.18 solar radii, together with Grazing Incidence Spectrometer (GIS) 4" x 4" rasters within the same field of view, out to 1.2 solar radii. The radial direction to Ulysses passed through a high latitude streamer, throughout the 4 days of observations, Analysis of the spectra taken by UVCS shows a variation of the element abundances in the streamer over our observing interval: however, because the observations were in slightly different parts of the streamer on different days, the variation could be ascribed either to a temporal or spatial effect. The oxygen abundance, however, seems to increase at the edge of the streamer, as indicated by previous analyses. This suggests the variation may be a function of position within the streamer, rather than a temporal effect. Oxygen abundances measured by SWICS on Ulysses are compared with the CDS and UVCS results to see whether changes measured in situ follow the same pattern.

  7. UVC-induced apoptosis in Dubca cells is independent of JNK activation and p53Ser-15 phosphorylation

    International Nuclear Information System (INIS)

    Chathoth, Shahanas; Thayyullathil, Faisal; Hago, Abdulkader; Shahin, Allen; Patel, Mahendra; Galadari, Sehamuddin

    2009-01-01

    Ultraviolet C (UVC) irradiation in mammalian cell lines activates a complex signaling network that leads to apoptosis. By using Dubca cells as a model system, we report the presence of a UVC-induced apoptotic pathway that is independent of c-Jun N-terminal kinases (JNKs) activation and p53 phosphorylation at Ser 15 . Irradiation of Dubca cells with UVC results in a rapid JNK activation and phosphorylation of its downstream target c-Jun, as well as, phosphorylation of activating transcription factor 2 (ATF2). Pre-treatment with JNK inhibitor, SP600125, inhibited UVC-induced c-Jun phosphorylation without preventing UVC-induced apoptosis. Similarly, inhibition of UVC-induced p53 phosphorylation did not prevent Dubca cell apoptosis, suggesting that p53 Ser-15 phosphorylation is not associated with UVC-induced apoptosis signaling. The pan-caspase inhibitor z-VAD-fmk inhibited UVC-induced PARP cleavage, DNA fragmentation, and ultimately apoptosis of Dubca cells. Altogether, our study clearly indicates that UVC-induced apoptosis is independent of JNK and p53 activation in Dubca cells, rather, it is mediated through a caspase dependent pathway. Our findings are not in line with the ascribed critical role for JNKs activation, and downstream phosphorylation of targets such as c-Jun and ATF2 in UVC-induced apoptosis.

  8. Conditions of lighting in reading-rooms located in public and school libraries in Silesian Voivodeship

    Directory of Open Access Journals (Sweden)

    Magdalena Sitek

    2013-06-01

    Full Text Available Introduction: Reading-room is a place where special lighting conditions are required to make the reader feel comfortable and satisfied.. Lighting requirements are enclosed in the Polish Standard PN-EN 12464-1:2004. Accordingly, illuminance in the reading-rooms should be 500 lx. The aim of the study was to measure illuminance in reading-rooms in various libraries and make relative comparisons to standard values. Material and methods: Measurements of illuminance were performed in 22 reading-rooms in Silesia Voivodeship. Half of them were made in public libraries and half in reading-rooms at junior lower high schools. Illuminance was measured in 5 measurement points in reading-rooms by digital lux meter Lx-105 manufactured by Lutron. Furthermore , 100 readers of school libraries and 89 readers of public libraries completed a questionnaire on lighting conditions in these places. Results: Only 5 out of 22 reading-rooms meet the requirements of the Polish Standard concerning illuminance. Only in one reading room at junior lower high school illuminance exceeded 500 lx. In two other reading places the requirements were met due to additional desk lamps. Despite the results, 76.4% of approached readers of public libraries and 60% of pupils think that lighting in readingrooms is satisfactory and almost 63% of the readers and 53% of the pupils don’t demand additional lighting. Conclusions: Most of the scrutinized reading rooms do not meet lighting requirements according to the Polish Standard. Lighting conditions in school libraries are worse than in public libraries. According to the respondents lighting in public libraries is adequate.

  9. Alternative strawberry disease management strategy: combing low UV-C irradiation in dark, disabling pathogen’s UV-C repair mechanism, and preventing pathogen establishment with biocontrol agents

    Science.gov (United States)

    The limitations of current fungicides necessitate a search for new approaches. Low-dose or sub-lethal UV-C irradiation (12.36 J/m2) alone is not effective in controlling fungal diseases, especially when the plants are exposed to UV-C irradiation during the day. We found, however, that application ...

  10. Thermodynamic Upper Bound on Broadband Light Coupling with Photonic Structures

    KAUST Repository

    Yu, Zongfu; Raman, Aaswath; Fan, Shanhui

    2012-01-01

    to an upper bound dictated by the second law of thermodynamics. Such bound limits how efficient light can be coupled to any photonic structure. As one example of application, we use this upper bound to derive the limit of light absorption in broadband solar

  11. Pathogen reduction by ultraviolet C light effectively inactivates human white blood cells in platelet products.

    Science.gov (United States)

    Pohler, Petra; Müller, Meike; Winkler, Carla; Schaudien, Dirk; Sewald, Katherina; Müller, Thomas H; Seltsam, Axel

    2015-02-01

    Residual white blood cells (WBCs) in cellular blood components induce a variety of adverse immune events, including nonhemolytic febrile transfusion reactions, alloimmunization to HLA antigens, and transfusion-associated graft-versus-host disease (TA-GVHD). Pathogen reduction (PR) methods such as the ultraviolet C (UVC) light-based THERAFLEX UV-Platelets system were developed to reduce the risk of transfusion-transmitted infection. As UVC light targets nucleic acids, it interferes with the replication of both pathogens and WBCs. This preclinical study aimed to evaluate the ability of UVC light to inactivate contaminating WBCs in platelet concentrates (PCs). The in vitro and in vivo function of WBCs from UVC-treated PCs was compared to that of WBCs from gamma-irradiated and untreated PCs by measuring cell viability, proliferation, cytokine secretion, antigen presentation in vitro, and xenogeneic GVHD responses in a humanized mouse model. UVC light was at least as effective as gamma irradiation in preventing GVHD in the mouse model. It was more effective in suppressing T-cell proliferation (>5-log reduction in the limiting dilution assay), cytokine secretion, and antigen presentation than gamma irradiation. The THERAFLEX UV-Platelets (MacoPharma) PR system can substitute gamma irradiation for TA-GVHD prophylaxis in platelet (PLT) transfusion. Moreover, UVC treatment achieves suppression of antigen presentation and inhibition of cytokine accumulation during storage of PCs, which has potential benefits for transfusion recipients. © 2014 AABB.

  12. Evaluating UV-C LED disinfection performance and ...

    Science.gov (United States)

    This study evaluated ultraviolet (UV) light emitting diodes (LEDs) emitting at 260 nm, 280 nm, and the combination of 260|280 nm together for their efficacy at inactivating Escherichia. coli, MS2 coliphage, human adenovirus type 2 (HAdV2), and Bacillus pumilus spores; research included an evaluation of genomic damage. Inactivation by the LEDs was compared with the efficacy of conventional UV sources, the low-pressure (LP) and medium-pressure (MP) mercury vapor lamps. The work also calculated the electrical energy per order of reduction of the microorganisms by the five UV sources.For E. coli, all five UV sources yielded similar inactivation rates. For MS2 coliphage, the 260 nm LED was most effective. For HAdV2 and B. pumilus, the MP UV lamp was significantly more effective than the LP UV and UVC LED sources. When considering electrical energy per order of reduction, the LP UV lamp was the most efficient for E. coli and MS2, and the MPUV and LPUV were equally efficient for HAdV2 and B. pumilus spores. Among the UVC LEDs, the 280 nm LED unit required the least energy per log reduction of E. coli and HAdV2. The 280 nm and 260|280 nm LED units were equally efficient per log reduction of B. pumilus spores, and the 260 nm LED unit required the lowest energy per order of reduction of MS2 coliphage. The combination of the 260 nm and 280 nm UV LED wavelengths was also evaluated for potential synergistic effects. No dual-wavelength synergy was detected for inactivation of

  13. Controlled UV-C light-induced fusion of thiol-passivated gold nanoparticles.

    Science.gov (United States)

    Pocoví-Martínez, Salvador; Parreño-Romero, Miriam; Agouram, Said; Pérez-Prieto, Julia

    2011-05-03

    Thiol-passivated gold nanoparticles (AuNPs) of a relatively small size, either decorated with chromophoric groups, such as a phthalimide (Au@PH) and benzophenone (Au@BP), or capped with octadecanethiol (Au@ODCN) have been synthesized and characterized by NMR and UV-vis spectroscopy as well as transmission electron microscopy (TEM). These NPs were irradiated in chloroform at different UV-wavelengths using either a nanosecond laser (266 and 355 nm, ca. 12 mJ/pulse, 10 ns pulse) or conventional lamps (300 nm UV-vis spectroscopy, as well as by TEM. Laser irradiation at 355 nm led to NP aggregation and precipitation, while the NPs were photostable under UV-A lamp illumination. Remarkably, laser excitation at 266 nm induced a fast (minutes time-scale) increase in the size of the NPs, producing huge spherical nanocrystals, while lamp-irradiation at UV-C wavelengths brought about nanonetworks of partially fused NPs with a larger diameter than the native NPs.

  14. Splenic Abscess: A Rare Complication of the UVC in Newborn

    Directory of Open Access Journals (Sweden)

    Ameer Aslam

    2014-01-01

    Full Text Available Splenic abscess is one of the rarest complications of the UVC in a newborn and it is hypothesized that it could be due to an infection or trauma caused by a catheter. The case that is being reported presented with abdominal distension and recurrent desaturation with suspicion of neonatal sepsis versus necrotizing enterocolitis. However, the final diagnosis was splenic abscess as a complication of an inappropriate UVC insertion which was discovered by abdominal ultrasound. The patient was given broad spectrum antibiotics empirically and the symptoms were resolved without any surgical intervention. Such cases and controlled studies need to be reported in order to identify further causes and risk factors associated with splenic abscess in a patient with UVC which can eventually help us adopt preventive strategies to avoid such complications.

  15. Effect of coupled UV-A and UV-C LEDs on both microbiological and chemical pollution of urban wastewaters

    International Nuclear Information System (INIS)

    Chevremont, A.-C.; Farnet, A.-M.; Coulomb, B.; Boudenne, J.-L.

    2012-01-01

    Wastewater reuse for irrigation is an interesting alternative for many Mediterranean countries suffering from water shortages. The development of new technologies for water recycling is a priority for these countries. In this study we test the efficiency of UV-LEDs (Ultraviolet-Light-Emitting Diodes) emitting UV-A or UV-C radiations, used alone or coupled, on bacterial and chemical indicators. We monitored the survival of fecal bioindicators found in urban wastewaters and the oxidation of creatinine and phenol which represent either conventional organic matter or the aromatic part of pollution respectively. It appears that coupling UV-A/UV-C i) achieves microbial reduction in wastewater more efficiently than when a UV-LED is used alone, and ii) oxidizes up to 37% of creatinine and phenol, a result comparable to that commonly obtained with photoreactants such as TiO 2 . - Highlights: ► We test UV-LEDs as an urban wastewater tertiary treatment. ► UV-A and UV-C are coupled, combining germicidal and oxidative properties of UV. ► Coupled wavelengths have the most efficient bactericidal effect. ► Coupling UV-A and UV-C leads to photooxidation of creatinine and phenol.

  16. Repair of UVC induced DNA lesions in erythrocytes from Carassius auratus gibelio

    International Nuclear Information System (INIS)

    Bagdonas, E.; Zukas, K.

    2004-01-01

    The kinetics of UVC (254 nm) irradiation induced DNA single-strand breaks generated during the excision repair of UV induced DNA damage in erythrocytes from Carassius auratus gibelio were studied using alkaline comet assay. Nucleotide excision repair recognised DNA lesions such as UVC induced cyclobutane pyrimidine dimers and 6-4 pyrimidine-pyrimidone photoproducts and produced DNA single-stranded breaks that were easily detected by comet assay. After irradiation of erythrocytes with 58 j/m 2 UVC dose, there was an increase in comet tail moment (CTM) at 2 hours post-radiation, whereas at 4 hours post-radiation CTM decreased and did not differ significantly from the control level (P=0,127). When erythrocytes were exposed to 173 J/m 2 UVC dose, the excision repair delayed in the beginning (0 hours), reached maximum level at 2 hours post-radiation (CTM-54,8) and showed slightly decreased level at 4 hours post-radiation (CTM=18,5). (author)

  17. Two pathogen reduction technologies--methylene blue plus light and shortwave ultraviolet light--effectively inactivate hepatitis C virus in blood products.

    Science.gov (United States)

    Steinmann, Eike; Gravemann, Ute; Friesland, Martina; Doerrbecker, Juliane; Müller, Thomas H; Pietschmann, Thomas; Seltsam, Axel

    2013-05-01

    Contamination of blood products with hepatitis C virus (HCV) can cause infections resulting in acute and chronic liver diseases. Pathogen reduction methods such as photodynamic treatment with methylene blue (MB) plus visible light as well as irradiation with shortwave ultraviolet (UVC) light were developed to inactivate viruses and other pathogens in plasma and platelet concentrates (PCs), respectively. So far, their inactivation capacities for HCV have only been tested in inactivation studies using model viruses for HCV. Recently, a HCV infection system for the propagation of infectious HCV in cell culture was developed. Inactivation studies were performed with cell culture-derived HCV and bovine viral diarrhea virus (BVDV), a model for HCV. Plasma units or PCs were spiked with high titers of cell culture-grown viruses. After treatment of the blood units with MB plus light (Theraflex MB-Plasma system, MacoPharma) or UVC (Theraflex UV-Platelets system, MacoPharma), residual viral infectivity was assessed using sensitive cell culture systems. HCV was sensitive to inactivation by both pathogen reduction procedures. HCV in plasma was efficiently inactivated by MB plus light below the detection limit already by 1/12 of the full light dose. HCV in PCs was inactivated by UVC irradiation with a reduction factor of more than 5 log. BVDV was less sensitive to the two pathogen reduction methods. Functional assays with human HCV offer an efficient tool to directly assess the inactivation capacity of pathogen reduction procedures. Pathogen reduction technologies such as MB plus light treatment and UVC irradiation have the potential to significantly reduce transfusion-transmitted HCV infections. © 2012 American Association of Blood Banks.

  18. Comparison of hospital room surface disinfection using a novel ultraviolet germicidal irradiation (UVGI) generator.

    Science.gov (United States)

    Jelden, Katelyn C; Gibbs, Shawn G; Smith, Philip W; Hewlett, Angela L; Iwen, Peter C; Schmid, Kendra K; Lowe, John J

    2016-09-01

    The estimated 721,800 hospital acquired infections per year in the United States have necessitated development of novel environmental decontamination technologies such as ultraviolet germicidal irradiation (UVGI). This study evaluated the efficacy of a novel, portable UVGI generator (the TORCH, ChlorDiSys Solutions, Inc., Lebanon, NJ) to disinfect surface coupons composed of plastic from a bedrail, stainless steel, chrome-plated light switch cover, and a porcelain tile that were inoculated with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus faecalis (VRE). Each surface type was placed at 6 different sites within a hospital room and treated by 10-min ultraviolet-C (UVC) exposures using the TORCH with doses ranging from 0-688 mJ/cm(2) between sites. Organism reductions were compared with untreated surface coupons as controls. Overall, UVGI significantly reduced MRSA by an average of 4.6 log10 (GSD: 1.7 log10, 77% inactivation, p surfaces, while VRE was reduced significantly less on chrome (p = 0.0004) and stainless steel (p = 0.0012) than porcelain tile. Organisms out of direct line of sight of the UVC generator were reduced significantly less (p surfaces evaluated within the hospital environment in direct line of sight of UVGI treatment with variation between organism and surface types.

  19. Effect of coupled UV-A and UV-C LEDs on both microbiological and chemical pollution of urban wastewaters

    Energy Technology Data Exchange (ETDEWEB)

    Chevremont, A.-C., E-mail: anne-celine.chevremont@imbe.fr [Aix-Marseille Universite - CNRS, FR ECCOREV, Laboratoire Chimie de l' Environnement (FRE3416), Equipe ' Developpements Metrologiques et Chimie des Milieux' , 3 place Victor Hugo, case 29, 13331 Marseille Cedex 3 (France); Aix-Marseille Universite - CNRS, FR ECCOREV, Institut Mediterraneen de Biodiversite et d' Ecologie marine et continentale (UMR7263), Equipe ' Vulnerabilite des Systemes Microbiens' , Avenue Escadrille Normandie-Niemen, Boite 452, 13397 Marseille Cedex 20 (France); Farnet, A.-M. [Aix-Marseille Universite - CNRS, FR ECCOREV, Institut Mediterraneen de Biodiversite et d' Ecologie marine et continentale (UMR7263), Equipe ' Vulnerabilite des Systemes Microbiens' , Avenue Escadrille Normandie-Niemen, Boite 452, 13397 Marseille Cedex 20 (France); Coulomb, B.; Boudenne, J.-L. [Aix-Marseille Universite - CNRS, FR ECCOREV, Laboratoire Chimie de l' Environnement (FRE3416), Equipe ' Developpements Metrologiques et Chimie des Milieux' , 3 place Victor Hugo, case 29, 13331 Marseille Cedex 3 (France)

    2012-06-01

    Wastewater reuse for irrigation is an interesting alternative for many Mediterranean countries suffering from water shortages. The development of new technologies for water recycling is a priority for these countries. In this study we test the efficiency of UV-LEDs (Ultraviolet-Light-Emitting Diodes) emitting UV-A or UV-C radiations, used alone or coupled, on bacterial and chemical indicators. We monitored the survival of fecal bioindicators found in urban wastewaters and the oxidation of creatinine and phenol which represent either conventional organic matter or the aromatic part of pollution respectively. It appears that coupling UV-A/UV-C i) achieves microbial reduction in wastewater more efficiently than when a UV-LED is used alone, and ii) oxidizes up to 37% of creatinine and phenol, a result comparable to that commonly obtained with photoreactants such as TiO{sub 2}. - Highlights: Black-Right-Pointing-Pointer We test UV-LEDs as an urban wastewater tertiary treatment. Black-Right-Pointing-Pointer UV-A and UV-C are coupled, combining germicidal and oxidative properties of UV. Black-Right-Pointing-Pointer Coupled wavelengths have the most efficient bactericidal effect. Black-Right-Pointing-Pointer Coupling UV-A and UV-C leads to photooxidation of creatinine and phenol.

  20. Making equipment to process paddy water for providing drinking water by using Ozone-UVC& Ultrafiltration

    Science.gov (United States)

    Styani, E.; Dja'var, N.; Irawan, C.; Hanafi

    2018-01-01

    This study focuses on making equipment which is useful to process paddy water to be consumable as drinking water by using ozone-UVC and ultrafiltration. The equipment which is made by the process of ozone-UVC and ultrafiltration or reverse osmosis is driven by electric power generated from solar panels. In the experiment, reverse osmosis system with ozone-UVC reactor proves to be good enough in producing high quality drinking water.

  1. Heated water and UV-C radiation to post harvest control of Cryptosporiopsis perennans on apples; Agua aquecida e radiacao UV-C no controle pos-colheita de Cryptosporiopsis perennans em macas

    Energy Technology Data Exchange (ETDEWEB)

    Bartnicki, Vinicius Adao; Amarante, Cassandro Vidal Talamini do, E-mail: vinibart@hotmail.co, E-mail: amarante@cav.udesc.b [Universidade do Estado de Santa Catarina (UDESC), Lages, SC (Brazil). Centro de Ciencias Agroveterinarias. Dept. de Agronomia; Valdebenito-Sanhueza, Rosa Maria, E-mail: rosamaria@m2net.com.b [Proterra Engenharia Agronomica, Vacaria, RS (Brazil); Castro, Luis Antonio Suita de, E-mail: suita@cpact.embrapa.b [EMBRAPA Clima Temperado, Pelotas, RS (Brazil); Rizzatti, Mara Regina; Souza, Joao Antonio Vargas de, E-mail: marar@pucrs.b [Pontificia Universidade Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Centro em Pesquisa e Desenvolvimento em Fisica. Grupo de Fisica das Radiacoes

    2010-02-15

    The objective of this work was to assess the colonization of Cryptosporiopsis perennans in the epidermis of apples and the efficiency of heated water and UV-C radiation application to control this pathogen. In apples inoculated with C. perennans, the colonization of lenticels and adjacent areas by the pathogen was observed by electronic scanning microscopy. The sensitivity of C. perennans conidia was evaluated in aqueous suspension, at temperatures of 28, 45, 50 and 55 deg C for 15 and 30 s, and at UV.C radiation doses of 0.018, 0.037, 0.075, 0.150, 0.375, 0.750, 1.500 and 3.000 kJ m.2. The effects of UV.C radiation doses at 0.375, 0.750 and 1.500 kJ m.2 and heated water at 50 deg C, sprayed during 15 and 30 s were evaluated for controlling C. perennans in apples inoculated with the pathogen. The fungus produced abundant mycelium and conidia in lenticels and adjacent areas on the epidermis of the apples. The heated water at 50 deg C during 15 s and a 0.750 kJ m.2 UV.C radiation dose reduced conidia survival in more than 99%. Heated water sprayed at 50 deg C during 15 s and a UV.C radiation dose of 0.375 kJ m.2 control C. perennans in apples. (author)

  2. Enhanced terminal room disinfection and acquisition and infection caused by multidrug-resistant organisms and Clostridium difficile (the Benefits of Enhanced Terminal Room Disinfection study): a cluster-randomised, multicentre, crossover study

    Science.gov (United States)

    Anderson, Deverick J; Chen, Luke F; Weber, David J; Moehring, Rebekah W; Lewis, Sarah S; Triplett, Patricia F; Blocker, Michael; Becherer, Paul; Schwab, J Conrad; Knelson, Lauren P; Lokhnygina, Yuliya; Rutala, William A; Kanamori, Hajime; Gergen, Maria F; Sexton, Daniel J

    2018-01-01

    Summary Background Patients admitted to hospital can acquire multidrug-resistant organisms and Clostridium difficile from inadequately disinfected environmental surfaces. We determined the effect of three enhanced strategies for terminal room disinfection (disinfection of a room between occupying patients) on acquisition and infection due to meticillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, C difficile, and multidrug-resistant Acinetobacter. Methods We did a pragmatic, cluster-randomised, crossover trial at nine hospitals in the southeastern USA. Rooms from which a patient with infection or colonisation with a target organism was discharged were terminally disinfected with one of four strategies: reference (quaternary ammonium disinfectant except for C difficile, for which bleach was used); UV (quaternary ammonium disinfectant and disinfecting ultraviolet [UV-C] light except for C difficile, for which bleach and UV-C were used); bleach; and bleach and UV-C. The next patient admitted to the targeted room was considered exposed. Every strategy was used at each hospital in four consecutive 7-month periods. We randomly assigned the sequence of strategies for each hospital (1:1:1:1). The primary outcomes were the incidence of infection or colonisation with all target organisms among exposed patients and the incidence of C difficile infection among exposed patients in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT01579370. Findings 31 226 patients were exposed; 21 395 (69%) met all inclusion criteria, including 4916 in the reference group, 5178 in the UV group, 5438 in the bleach group, and 5863 in the bleach and UV group. 115 patients had the primary outcome during 22 426 exposure days in the reference group (51·3 per 10 000 exposure days). The incidence of target organisms among exposed patients was significantly lower after adding UV to standard cleaning strategies (n=76; 33·9 cases per 10 000

  3. PENGARUH FOTOOKSIDASI UV-C TERHADAP SIFAT FISIKOKIMIA DAN BAKING EXPANSION PATI SAGU (Metroxylon sago

    Directory of Open Access Journals (Sweden)

    Eduard Fransisco Tethool

    2017-09-01

    Full Text Available Native Sago starch is difficult to used in industry because of the limitations of its phisycochemical properties. The aim of this research was to studied effect of UV-C photo-oxidation on  physicochemical properties and baking expansion of sago starch. Five slurries ratio (starch : water ratio: 1:2; 1:4; 1:6; 1:8; and 1:10 were oxidized with UV-C irradiation for 20 minutes, and then compared with native sago starch. The results showed that UV-C photo-oxidation increasing amylose content and paste viscosity, but decreasing swelling power and solubility, and carbonyl and carboxyl content. Used of UV-C as a photooxidator effective to increasing baking expansion characteristic, and the best slurry ratio was 1:6, which has 6.97 ml/g specific volume or 33.7% increased from native sago starch (5.22 ml/g

  4. Photomorphogenetic responses to UV radiation and short-term red light in lettuce seedlings

    International Nuclear Information System (INIS)

    Kobzar, E.F.; Kreslavski, V.D.; Muzafarov, E.N.

    1998-01-01

    Effects of red light (R), far-red light (FR) and UV radiation on growth and greening of lettuce seedlings (Latuca sativa L., cv. Berlinskii) have been investigated. UV-B and UV-C inhibited hypocotyl elongation and stimulated cotyledonary growth. R in combination with UV-B and UV-C partly eliminated these effects, but FR increased those and reversed the R effect. Chlorophyll accumulation was inhibited by UV-B and UV-C. In comparison with cotyledonary growth, R strengthened the UV inhibitory effect, and FR reversed this effect of R. Thus, UV and phytochrome system modify the effects of each other on hypocotyl and leaf growth in lettuce seedlings depending on the level of active phytochrome formed

  5. The association of subjective stress, urinary catecholamine concentrations and PC game room use and musculoskeletal disorders of the upper limbs in young male Koreans.

    Science.gov (United States)

    Kang, Jong-Won; Kim, Heon; Cho, Soo-Hun; Lee, Myung-Koo; Kim, Yong-Dae; Nan, Hong-Mei; Lee, Chul-Ho

    2003-06-01

    The use of PCs can cause health problems, including musculoskeletal disorders (MSDs) of the upper limbs. This study was performed to investigate whether using PCs in PC game rooms may induce MSDs of the upper limbs. 284 young male Koreans were included. A self-administered, structured questionnaire was used to gather information about game room use, perceived subjective stress, and the symptoms related to MSDs. Urinary concentrations of epinephrine, norepinephrine, and dopamine were measured in spot urine. The symptom prevalence of MSDs of the upper limbs increased according to the increase of the duration of game room use. The intensity of perceived subjective stress showed a significant dose-response relationship with the frequency of MSDs symptoms in neck and shoulder areas. However, the urinary level of catecholamines was not significantly correlated with the symptom prevalence of MSDs in the upper limbs. These findings suggest that using PCs in game rooms produce physical stress on the upper limbs, strong enough to induce MSDs.

  6. The effectiveness of UV-C radiation for facility-wide environmental disinfection to reduce health care-acquired infections.

    Science.gov (United States)

    Napolitano, Nathanael A; Mahapatra, Tanmay; Tang, Weiming

    2015-12-01

    Health care-acquired infections (HAIs) constitute an increasing threat for patients worldwide. Potential contributors of HAIs include environmental surfaces in health care settings, where ultraviolet-C radiation (UV-C) is commonly used for disinfection. This UV-C intervention-based pilot study was conducted in a hospital setting to identify any change in the incidence of HAIs before and after UV-C intervention, and to determine the effectiveness of UV-C in reducing pathogens. In a hospital in Culver City, CA, during 2012-2013, bactericidal doses of UV-C radiation (254 nm) were delivered through a UV-C-based mobile environmental decontamination unit. The UV-C dosing technology and expertise of the specifically trained personnel were provided together as a dedicated service model by a contracted company. The incidence of HAIs before and after the intervention period were determined and compared. The dedicated service model dramatically reduced HAIs (incidence difference, 1.3/1000 patient-days, a 34.2% reduction). Reductions in the total number and incidence proportions (28.8%) of HAIs were observed after increasing and maintaining the coverage of UV-C treatments. The dedicated service model was found to be effective in decreasing the incidence of HAIs, which could reduce disease morbidity and mortality in hospitalized patients. This model provides a continuously monitored and frequently UV-C-treated patient environment. This approach to UV-C disinfection was associated with a decreased incidence of HAIs. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  7. UVC-induced stress granules in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Mohamed Taha Moutaoufik

    Full Text Available Stress granules (SGs are well characterized cytoplasmic RNA bodies that form under various stress conditions. We have observed that exposure of mammalian cells in culture to low doses of UVC induces the formation of discrete cytoplasmic RNA granules that were detected by immunofluorescence staining using antibodies to RNA-binding proteins. UVC-induced cytoplasmic granules are not Processing Bodies (P-bodies and are bone fide SGs as they contain TIA-1, TIA-1/R, Caprin1, FMRP, G3BP1, PABP1, well known markers, and mRNA. Concomitant with the accumulation of the granules in the cytoplasm, cells enter a quiescent state, as they are arrested in G1 phase of the cell cycle in order to repair DNA damages induced by UVC irradiation. This blockage persists as long as the granules are present. A tight correlation between their decay and re-entry into S-phase was observed. However the kinetics of their formation, their low number per cell, their absence of fusion into larger granules, their persistence over 48 hours and their slow decay, all differ from classical SGs induced by arsenite or heat treatment. The induction of these SGs does not correlate with major translation inhibition nor with phosphorylation of the α subunit of eukaryotic translation initiation factor 2 (eIF2α. We propose that a restricted subset of mRNAs coding for proteins implicated in cell cycling are removed from the translational apparatus and are sequestered in a repressed form in SGs.

  8. Antioxidant enzymes expression in Pseudomonas aeruginosa exposed to UV-C radiation.

    Science.gov (United States)

    Salma, Kloula Ben Ghorbal; Lobna, Maalej; Sana, Khefacha; Kalthoum, Chourabi; Imene, Ouzari; Abdelwaheb, Chatti

    2016-07-01

    It was well known that, UV-C irradiation increase considerably the reactive oxygen species (ROS) levels in eukaryotic and prokaryotic organisms. In the enzymatic ROS-scavenging pathways, superoxide dismutase (SOD), Catalase (CAT), and peroxidase (POX) were developed to deal with oxidative stress. In this study, we investigated the effects of UV-C radiations on antioxidant enzymes (catalase, superoxide dismutase, and peroxidases) expression in Pseudomonas aeruginosa. Catalase, superoxide dismutase, and peroxidases activities were determined spectrophotometrically. Isozymes of superoxide dismutase were revealed by native gel activity staining method. Lipid peroxidation was determined by measuring malondialdehyde formation. Our results showed that superoxide dismutase, catalase and peroxidase activities exhibited a gradual increase during the exposure time (30 min). However, the superoxide dismutase activity was maximized at 15 min. Native gel activity staining assays showed the presence of three superoxide dismutase isozymes. The iron-cofactored isoform activity was altered after exposure to UV-C stress. These finding suggest that catalase and peroxidase enzymes have the same importance toward UV-C rays at shorter and longer exposure times and this may confer additional protection to superoxide dismutase from damage caused by lipid peroxidation. Moreover, our data demonstrate the significant role of the antioxidant system in the resistance of this important human pathogen. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Anthocyanin-rich extract from Hibiscus sabdariffa calyx counteracts UVC-caused impairments in rats.

    Science.gov (United States)

    Ozkol, Hatice Uce; Koyuncu, Ismail; Tuluce, Yasin; Dilsiz, Nihat; Soral, Sinan; Ozkol, Halil

    2015-01-01

    Ultraviolet radiation (UV) was reported to cause oxidative stress. Hibiscus sabdariffa L. (Malvaceae) calyx is commonly used in traditional Asian and African medicines and possesses strong antioxidant capacity due to its anthocyanin (ANTH) content. This study researched the possible protective role of Hibiscus sabdariffa calyx extract (HSCE) in UVC exposure of rats. Levels of serum enzymes, renal function tests, and some oxidant/antioxidant biomarkers of skin, lens, and retina tissues were monitored. Rats were exposed to UVC 4 h daily for 40 d and simultaneously received HSCE containing 2.5, 5, and 10 mg doses of ANTH in drinking water. Significant (p < 0.05) increases in the levels of serum aminotransferases, lactate dehydrogenase, urea, creatinine, and uric acid were noted after UVC exposure. In skin, lens, and retina tissues, total oxidant status, oxidative stress index, lipid peroxidation, and protein oxidation escalated markedly (p < 0.05) whereas total antioxidant status, reduced glutathione, and superoxide dismutase decreased dramatically (p < 0.05) related to UVC. Co-administration of HSCE with each ANTH dose significantly (p < 0.05) reversed aforementioned parameters (except total oxidant status) almost in all tissues. The LD50 of HSCE in rats was determined to be above 5000 mg/kg. Our data revealed that HSCE has a remarkable potential to counteract UVC-caused impairments, probably through its antioxidant and free radical-defusing effects. Therefore, HSCE could be useful against some cutaneous and ocular diseases in which UV and oxidative stress have a role in the etiopathogenesis.

  10. Detailed simulations of lighting conditions in office rooms lit by daylight and artificial light

    DEFF Research Database (Denmark)

    Iversen, Anne

    In this thesis the effect on the annual artificial lighting demand is investigated by employing detailed simulations of lighting conditions in office rooms lit by daylight and artificial. The simulations of the artificial lighting demand is accomplished through daylight simulations in Radiance....... The detailed simulations includes studies of the resolution of different weather data sets in climate-based daylight modeling. Furthermore, influence of the electrical lighting demand by simulating with dynamic occupancy patterns is studied. Finally the thesis explores the influence of obstructions in an urban...... canyon on the daylight availability within the buildings, and hence on the energy consumption for artificial lights. The results from the thesis demonstrates that the effect on the outcome of the daylight simulations when simulating with typical weather data files for the location of Copenhagen...

  11. Abscisic acid induces biosynthesis of bisbibenzyls and tolerance to UV-C in the liverwort Marchantia polymorpha.

    Science.gov (United States)

    Kageyama, Akito; Ishizaki, Kimitsune; Kohchi, Takayuki; Matsuura, Hideyuki; Takahashi, Kosaku

    2015-09-01

    Environmental stresses are effective triggers for the biosynthesis of various secondary metabolites in plants, and phytohormones such as jasmonic acid and abscisic acid are known to mediate such responses in flowering plants. However, the detailed mechanism underlying the regulation of secondary metabolism in bryophytes remains unclear. In this study, the induction mechanism of secondary metabolites in the model liverwort Marchantia polymorpha was investigated. Abscisic acid (ABA) and ultraviolet irradiation (UV-C) were found to induce the biosynthesis of isoriccardin C, marchantin C, and riccardin F, which are categorized as bisbibenzyls, characteristic metabolites of liverworts. UV-C led to the significant accumulation of ABA. Overexpression of MpABI1, which encodes protein phosphatase 2C (PP2C) as a negative regulator of ABA signaling, suppressed accumulation of bisbibenzyls in response to ABA and UV-C irradiation and conferred susceptibility to UV-C irradiation. These data show that ABA plays a significant role in the induction of bisbibenzyl biosynthesis, which might confer tolerance against UV-C irradiation in M. polymorpha. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. DNA repair after a UV-C irradiation in cultivated human fibroblasts: Studies on patients with actinic keratosis, spinocellular carcinoma and basal cell carcinoma as well as healthy controls

    International Nuclear Information System (INIS)

    Senner, A.

    1984-01-01

    Cultivated fibroblasts from 14 healthy control people and 22 patients were irradiated with UV-C light in increasing doses (0-1-2.5-5 mJ/cm 2 ). The incorporation of 3 H-thymidine in the DNA of the fibroblasts which is made visible by the autoradiography technique served as a measure for the unprogrammed DNA synthesis. All of the studied fibroblast types showed with an increase in the UV-C irradiation dose an increase in the repair processes of the DNA. No statistically significant difference could be shown in the repair behaviour of the fibroblasts of controls and patients. (orig./MG) [de

  13. Potential link between fruit yield, quality parameters and phytohormonal changes in preharvest UV-C treated strawberry.

    Science.gov (United States)

    Xu, Yanqun; Charles, Marie Thérèse; Luo, Zisheng; Roussel, Dominique; Rolland, Daniel

    2017-07-01

    Preharvest ultraviolet-C (UV-C) treatment of strawberry is a very new approach, and little information is available on the effect of this treatment on plant growth regulators. In this study, the effect of preharvest UV-C irradiations at three different doses on strawberry yield, fruit quality parameters and endogenous phytohormones was investigated simultaneously. The overall marketable yield of strawberry was not affected by the preharvest UV-C treatments, although more aborted and misshapen fruits were found in UV-C treated groups than in the untreated control. The fruits in the high dose group were firmer and had approximately 20% higher sucrose content and 15% higher ascorbic acid content than the control, while fruits from the middle and low dose groups showed no significant changes in these parameters. The lower abscisic acid (ABA) content found in the fruits in the high UV-C group may be associated with those quality changes. The citric acid content decreased only in the low dose group (reduction of 5.8%), with a concomitant 37% reduction in jasmonic acid (JA) content, compared to the control. The antioxidant status of fruits that received preharvest UV-C treatment was considered enhanced based on their oxygen radical absorbance capacity (ORAC) and malondialdehyde (MDA) content. In terms of aroma, three volatile alcohols differed significantly among the various treatments with obvious activation of alcohol acyltransferase (AAT) activity. The observed synchronous influence on physiological indexes and related phytohormones suggests that preharvest UV-C might affect fruit quality via the action of plant hormones. Crown Copyright © 2017. Published by Elsevier Masson SAS. All rights reserved.

  14. Microenvironments in swine farrowing rooms: the thermal, lighting, and acoustic environments of sows and piglets

    Directory of Open Access Journals (Sweden)

    Gabriela Munhoz Morello

    Full Text Available ABSTRACT: The present research hypothesized that the thermal, lighting and acoustic environments in commercial swine farrowing rooms vary over time and from crate to crate. This study was conducted on 27 replicates in two commercial farrowing rooms in North Central Indiana, each equipped with 60 farrowing crates. Temperature, relative humidity, light intensity, sound intensity, and air velocity were continuously monitored and estimated for each crate at the sow level, for 48 h post-farrowing, which is usually a critical period for piglet survivability. Average daily temperature for all the crates in Room 1 was 24.1 ± 2.0 °C, 1.0 °C lower (p < 0.05 than in Room 2. Although the overall mean temperature was similar between rooms and seasons, frequency distribution diagrams revealed that the proportion of time spent within distinct limits of mean daily temperature ranged from 15.0 °C to 28.0 °C and varied substantially between rooms and seasons. Similar results were found for all variables measured in this study. Differences in temperature, relative humidity, light intensity, air velocity, and sound intensity in crates were as high as 9.6 °C, 57 %, 3,847.3 Lx, 0.87 m s–1, and 38.7 dBC, respectively, in the same farrowing room when measured at the same instant. The results of the present research indicate that aspects that go beyond the physical environment of the sows, such as thermal, lighting, and acoustic environment can vary substantially over time and between crates of automatically climate controlled farrowing rooms. These differences should be taken into consideration in production setting and research.

  15. Thermodynamic Upper Bound on Broadband Light Coupling with Photonic Structures

    KAUST Repository

    Yu, Zongfu

    2012-10-01

    The coupling between free space radiation and optical media critically influences the performance of optical devices. We show that, for any given photonic structure, the sum of the external coupling rates for all its optical modes are subject to an upper bound dictated by the second law of thermodynamics. Such bound limits how efficient light can be coupled to any photonic structure. As one example of application, we use this upper bound to derive the limit of light absorption in broadband solar absorbers. © 2012 American Physical Society.

  16. Effect of UV-C radiation and hypergravity on germination, growth and content of chlorophyll of wheat seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Rupiasih, N. Nyoman, E-mail: rupiasih@gmail.com [Department of Physics, Udayana University, Bali (Indonesia); Vidyasagar, Pandit B., E-mail: prof-pbv@yahoo.com [Biophysics Laboratory, Department of Physics, University of Pune, Pune-411007 (India)

    2016-03-11

    An investigation of the effects of UV-C radiation and hypergravity on germination, growth and content of chlorophyll of wheat seedlings has been done. The UV-C irradiation periods of exposure were 30, 60, 90, 120 and 180 minutes. The hypergravity used were 1000 g, 2000 g and 2500 g. The combination treatment is UV-C irradiation for 180 min followed by each hypergravity. The results showed that irradiation of UV-C on wheat seeds have stimulated the seed germination, but hypergravity and combination treatments on wheat seeds have inhibited the seed germination. Those treatments gave negative effects to growth rate, the content of chlorophyll a, b and total chlorophyll of wheat seedlings.

  17. Effect of UV-C radiation and hypergravity on germination, growth and content of chlorophyll of wheat seedlings

    International Nuclear Information System (INIS)

    Rupiasih, N. Nyoman; Vidyasagar, Pandit B.

    2016-01-01

    An investigation of the effects of UV-C radiation and hypergravity on germination, growth and content of chlorophyll of wheat seedlings has been done. The UV-C irradiation periods of exposure were 30, 60, 90, 120 and 180 minutes. The hypergravity used were 1000 g, 2000 g and 2500 g. The combination treatment is UV-C irradiation for 180 min followed by each hypergravity. The results showed that irradiation of UV-C on wheat seeds have stimulated the seed germination, but hypergravity and combination treatments on wheat seeds have inhibited the seed germination. Those treatments gave negative effects to growth rate, the content of chlorophyll a, b and total chlorophyll of wheat seedlings.

  18. Effect of ultraviolet-C light on postharvest decay of strawberry

    International Nuclear Information System (INIS)

    Nigro, F.; Ippolito, A.; Salerno, M.; Lattanzio, V.

    2000-01-01

    The effect of ultraviolet-C light (u.v.-C) at low doses on postharvest decay of strawberries caused by Botrytis cinerea and other pathogens was investigated. Phenylalanine ammonia-lyase (PAL) activity and ethylene production, as influenced by ultraviolet-C irradiation, were also determined. Strawberries (cv. ‘Pajaro’) from plants that had been treated with chemicals against grey mould were irradiated with u.v.-C doses ranging from 0.25 to 4.00 kJ m-2 and inoculated with B. cinerea at different times (0, 12, 24 and 48 hours) after irradiation. To assess the effect of u.v.-C light on the naturally occurring postharvest decay, organically grown strawberries were also used. After treatment the strawberries were stored at 20±1°C or at 3°C. u.v.-C doses at 0.50 and 1.00 kJ m-2 significantly reduced botrytis storage rot arising from both artificial inoculations and natural infections in comparison with the unirradiated control. The doses shown to reduce botrytis rot produced an increase in PAL activity 12 h after irradiation; this result indicates the activation of metabolic a pathway related to the biosynthesis of phenolic compounds, which are usually characterized by antifungal activity. In addition, u.v.-C irradiation caused an increase in ethylene production proportional to the doses applied, reaching the highest value 6 h after treatment. The overall results from these investigations indicate that treatment with low u.v.-C doses produces a reduction in postharvest decay of strawberries related to induced resistance mechanisms. Moreover, a germicidal effect of reducing external contaminating pathogens cannot be excluded

  19. Survival of thermophilic and hyperthermophilic microorganisms after exposure to UV-C, ionizing radiation and desiccation.

    Science.gov (United States)

    Beblo, Kristina; Douki, Thierry; Schmalz, Gottfried; Rachel, Reinhard; Wirth, Reinhard; Huber, Harald; Reitz, Günther; Rettberg, Petra

    2011-11-01

    In this study, we investigated the ability of several (hyper-) thermophilic Archaea and phylogenetically deep-branching thermophilic Bacteria to survive high fluences of monochromatic UV-C (254 nm) and high doses of ionizing radiation, respectively. Nine out of fourteen tested microorganisms showed a surprisingly high tolerance against ionizing radiation, and two species (Aquifex pyrophilus and Ignicoccus hospitalis) were even able to survive 20 kGy. Therefore, these species had a comparable survivability after exposure to ionizing radiation such as Deinococcus radiodurans. In contrast, there was nearly no difference in survival of the tested strains after exposure to UV-C under anoxic conditions. If the cells had been dried in advance of UV-C irradiation, they were more sensitive to UV-C radiation compared with cells irradiated in liquid suspension; this effect could be reversed by the addition of protective material like sulfidic ores before irradiation. By exposure to UV-C, photoproducts were formed in the DNA of irradiated Archaea and Bacteria. The distribution of the main photoproducts was species specific, but the amount of the photoproducts was only partly dependent on the applied fluence. Overall, our results show that tolerance to radiation seems to be a common phenomenon among thermophilic and hyperthermophilic microorganisms.

  20. High reflectivity YDH/SiO2 distributed Bragg reflector for UV-C wavelength regime

    KAUST Repository

    Alias, Mohd Sharizal

    2018-02-15

    A distributed Bragg reflector (DBR) composed of Y2O3-doped HfO2 (YDH)/SiO2 layers with high reflectivity spectrum centered at a wavelength of ~240 nm is deposited using radio-frequency magnetron sputtering. Before the DBR deposition, optical properties for a single layer of YDH, SiO2, and HfO2 thin films were studied using spectroscopic ellipsometry and spectrophotometry. To investigate the performance of YDH as a material for the high refractive index layer in the DBR, a comparison of its optical properties was made with HfO2 thin films. Due to larger optical bandgap, the YDH thin films demonstrated higher transparency, lower extinction coefficient, and lower absorption coefficient in the UV-C regime (especially for wavelengths below 250 nm) compared to the HfO2 thin films. The deposited YDH/SiO2 DBR consisting of 15 periods achieved a reflectivity higher than 99.9% at the wavelength of ~240 nm with a stopband of ~50 nm. The high reflectivity and broad stopband of YDH/SiO2 DBRs will enable further advancement of various photonic devices such as vertical-cavity surface-emitting lasers, resonant-cavity light-emitting diodes, and resonant-cavity photodetectors operating in the UV-C wavelength regime.

  1. Intensification of UV-C tertiary treatment: Disinfection and removal of micropollutants by sulfate radical based Advanced Oxidation Processes.

    Science.gov (United States)

    Rodríguez-Chueca, J; García-Cañibano, C; Lepistö, R-J; Encinas, Á; Pellinen, J; Marugán, J

    2018-04-21

    This study explores the enhancement of UV-C tertiary treatment by sulfate radical based Advanced Oxidation Processes (SR-AOPs), including photolytic activation of peroxymonosulfate (PMS) and persulfate (PS) and their photocatalytic activation using Fe(II). Their efficiency was assessed both for the inactivation of microorganisms and the removal or micropollutants (MPs) in real wastewater treatment plant effluents. Under the studied experimental range (UV-C dose 5.7-57 J/L; UV-C contact time 3 to 28 s), the photolysis of PMS and PS (0.01 mM) increased up to 25% the bacterial removal regarding to UV-C system. The photolytic activation of PMS led to the total inactivation of bacteria (≈ 5.70 log) with the highest UV-C dose (57 J/L). However, these conditions were insufficient to remove the MPs, being required oxidant's dosages of 5 mM to remove above 90% of carbamazepine, diclofenac, atenolol and triclosan. The best efficiencies were achieved by the combination of PMS or PS with Fe(II), leading to the total removal of the MPs using a low UV-C dosage (19 J/L), UV-C contact time (9 s) and reagent's dosages (0.5 mM). Finally, high mineralization was reached (>50%) with photocatalytic activation of PMS and PS even with low reagent's dosages. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Postharvest stilbenes and flavonoids enrichment of table grape cv Redglobe (Vitis vinifera L.) as affected by interactive UV-C exposure and storage conditions.

    Science.gov (United States)

    Crupi, Pasquale; Pichierri, Arianna; Basile, Teodora; Antonacci, Donato

    2013-11-15

    Flavonoids and stilbenes are secondary metabolites produced in plants that can play an important health-promoting role. The biosynthesis of these compounds generally increases as a response to biotic or abiotic stress; therefore, in order to achieve as high phenolic accumulation as possible, the interactive effects of storage conditions (temperature and time) and UV-C radiation on polyphenols content in postharvest Redglobe table grape variety were investigated. During a storage time longer than 48h, both cold storage (4°C) and UV-C exposure of almost 3min (2.4kJm(-2)) positively enhanced the content of cis- and trans-piceid (34 and 90μgg(-1) of skin, respectively) together with quercetin-3-O-galactoside and quercetin-3-O-glucoside (15 and 140μgg(-1) of skin, respectively) up to three fold respect to control grape samples. Conversely, catechin was not significantly affected by irradiation and storage treatments. With regard anthocyanins, the highest concentrations of cyanidin-3-O-glucoside and peonidin-3-Oglucoside were observed in Redglobe, stored at both room temperature and 4°C, after 5min (4.1kJm(-2)) of UV-C treatment and 24h of storage. Gathered findings showed that combined postharvest treatments can lead to possible "functional" grapes, within normal conditions of market commercialization, responding to the rising consumers demand to have foods that support and promote health. Copyright © 2013. Published by Elsevier Ltd.

  3. Room temperature current injection polariton light emitting diode with a hybrid microcavity.

    Science.gov (United States)

    Lu, Tien-Chang; Chen, Jun-Rong; Lin, Shiang-Chi; Huang, Si-Wei; Wang, Shing-Chung; Yamamoto, Yoshihisa

    2011-07-13

    The strong light-matter interaction within a semiconductor high-Q microcavity has been used to produce half-matter/half-light quasiparticles, exciton-polaritons. The exciton-polaritons have very small effective mass and controllable energy-momentum dispersion relation. These unique properties of polaritons provide the possibility to investigate the fundamental physics including solid-state cavity quantum electrodynamics, and dynamical Bose-Einstein condensates (BECs). Thus far the polariton BEC has been demonstrated using optical excitation. However, from a practical viewpoint, the current injection polariton devices operating at room temperature would be most desirable. Here we report the first realization of a current injection microcavity GaN exciton-polariton light emitting diode (LED) operating under room temperature. The exciton-polariton emission from the LED at photon energy 3.02 eV under strong coupling condition is confirmed through temperature-dependent and angle-resolved electroluminescence spectra.

  4. COMPARATIVE ANALYSIS OF UV-C AND UV-B RADIATION INFLUENCE ON PLANT OBJECTS

    Directory of Open Access Journals (Sweden)

    О. Міхєєв

    2011-04-01

    Full Text Available General aim of work – comparative research of temporal regularities of growth processes of pea,that was grown under normal conditions and with application of UV-C and UV-B irradiation ofstem part, and also detection of irradiation dose relations to parameter of root and stem part sproutsgrowth rate of Aronis pea. Research subject of UV-C and UV-B irradiation influence on dynamicsof plant growth parameters in each set of experiments was alteration of growth rate, pecularities ofgrowth dynamics in different conditions of experiment, detection of UV-C and UV-B irradiationdoses range, that stimulate or inhibit growth parameters of pea sprouts. The investigation resulted indetermination 1,3 times higher efficiency of UV-V irradiation comparing to UV-B irradiation.Reaction of root didn’t depend on the type of UV-radiation

  5. Heated water and UV-C radiation to post harvest control of Cryptosporiopsis perennans on apples

    International Nuclear Information System (INIS)

    Bartnicki, Vinicius Adao; Amarante, Cassandro Vidal Talamini do; Castro, Luis Antonio Suita de; Rizzatti, Mara Regina; Souza, Joao Antonio Vargas de

    2010-01-01

    The objective of this work was to assess the colonization of Cryptosporiopsis perennans in the epidermis of apples and the efficiency of heated water and UV-C radiation application to control this pathogen. In apples inoculated with C. perennans, the colonization of lenticels and adjacent areas by the pathogen was observed by electronic scanning microscopy. The sensitivity of C. perennans conidia was evaluated in aqueous suspension, at temperatures of 28, 45, 50 and 55 deg C for 15 and 30 s, and at UV.C radiation doses of 0.018, 0.037, 0.075, 0.150, 0.375, 0.750, 1.500 and 3.000 kJ m.2. The effects of UV.C radiation doses at 0.375, 0.750 and 1.500 kJ m.2 and heated water at 50 deg C, sprayed during 15 and 30 s were evaluated for controlling C. perennans in apples inoculated with the pathogen. The fungus produced abundant mycelium and conidia in lenticels and adjacent areas on the epidermis of the apples. The heated water at 50 deg C during 15 s and a 0.750 kJ m.2 UV.C radiation dose reduced conidia survival in more than 99%. Heated water sprayed at 50 deg C during 15 s and a UV.C radiation dose of 0.375 kJ m.2 control C. perennans in apples. (author)

  6. UV-C irradiation disrupts platelet surface disulfide bonds and activates the platelet integrin alphaIIbbeta3

    NARCIS (Netherlands)

    Verhaar, Robin; Dekkers, David W. C.; de Cuyper, Iris M.; Ginsberg, Mark H.; de Korte, Dirk; Verhoeven, Arthur J.

    2008-01-01

    UV-C irradiation has been shown to be effective for pathogen reduction in platelet concentrates, but preliminary work indicated that UV-C irradiation of platelets can induce platelet aggregation. In this study, the mechanism underlying this phenomenon was investigated. Irradiation of platelets with

  7. Model animal experiments on UV-c irradiation of blood and isolated cell populations

    International Nuclear Information System (INIS)

    Repke, H.; Scherf, H.P.; Wiesner, S.

    1984-01-01

    The cellular and molecular basis of the therapeutically used effect of reinjected ultraviolet (UVC) irradiated blood is unknown. First approaches to that problem were made in this study by aid of model experiments. Neither the spontaneous degranulation nor the antigen-induced histamine release from rat connective tissue mast cells (in vivo) was influenced by the injection (i.v.) of UV-irradiated blood or blood lymphocytes. By comparison of the effect of UV light on blood lymphocytes (number of dead cells, strength of chemoluminescence) after irradiation of the isolated cells and the unfractionated blood, respectively, it was shown that the strong light absorption within the blood sample prevents damage or functional alterations of the blood lymphocytes. The compound 48/80 - induced histamine release from rat peritoneal mast cells can be completely inhibited by UV irradiation (0.6 mJ/cm 2 ) without increasing the spontaneous histamine release. (author)

  8. Customization of flexographic printing plates related to uvc-induced changes in the crosslinking degree

    Directory of Open Access Journals (Sweden)

    Tamara Tomašegović

    2016-11-01

    Full Text Available In this paper, the swelling properties of photopolymer flexographic printing plates related to the variations of UVC post-treatment have been analysed. The aim of the research was to interconnect the changes in the crosslinking degree of the photopolymer material occurring due to the modified UVC radiation of the printing plate and the changes of its surface free energy crucial in the graphic reproduction process. Changes in the crosslinking degree in the photopolymer materials have been analysed by the swelling experiments. Results have proven that the partial dissolution of the photopolymer material caused by the immersion of the printing plates in various solvents is in the direct relation with the changes of the dispersive surface free energy. UVC post-treatment, used for the crosslinking termination and the definition of the surface properties of printing plates, is therefore directly affecting the resistivity of the printing plate in the solvent environment. By calculating the correlation coefficients for the weight loss of the photopolymer material in solvents and the dispersive surface free energy, the relation between the crosslinking degree and the UVC post-treatment has been established.

  9. Experimental Evolution of UV-C Radiation Tolerance: Emergence of Adaptive and Non-Adaptive Traits in Escherichia coli Under Differing Flux Regimes

    Science.gov (United States)

    Moffet, A.; Okansinski, A.; Sloan, C.; Grace, J. M.; Paulino-Lima, I. G.; Gentry, D.; Rothschild, L. J.; Camps, M.

    2014-12-01

    High-energy ultraviolet (UV-C) radiation is a significant challenge to life in environments such as high altitude areas, the early Earth, the Martian surface, and space. As UV-C exposure is both a selection pressure and a mutagen, adaptation dynamics in such environments include a high rate of change in both tolerance-related and non-tolerance-related genes, as well changes in linkages between the resulting traits. Determining the relationship between the intensity and duration of the UV-C exposure, mutation rate, and emergence of UV-C resistance will inform our understanding of both the emergence of radiation-related extremophily in natural environments and the optimal strategies for generating artificial extremophiles. In this study, we iteratively exposed an Escherichia colistrain to UV-C radiation of two different fluxes, 3.3 J/m^2/s for 6 seconds and 0.5 J/m^2/s for 40 seconds, with the same overall fluence of 20 J/m^2. After each iteration, cells from each exposure regime were assayed for increased UV-C tolerance as an adaptive trait. The exposed cells carried a plasmid bearing a TEM beta-lactamase gene, which in the absence of antibiotic treatment is a neutral reporter for mutagenesis. Sequencing of this gene allowed us to determine the baseline mutation frequency for each flux. As an additional readout for adaptation, the presence of extended-spectrum beta-lactamase mutations was tested by plating UV-exposed cultures in cefotaxime plates. We observed an increase of approximately one-million-fold in UV-C tolerance over seven iterations; no significant difference between the two fluxes was found. Future work will focus on identifying the genomic changes responsible for the change in UV-C tolerance; determining the mechanisms of the emerged UV-C tolerance; and performing competition experiments between the iteration strains to quantify fitness tradeoffs resulting from UV-C adaptation.

  10. Survival of thermophilic and hyper-thermophilic microorganisms after exposure to UV-C, ionizing radiation and desiccation

    International Nuclear Information System (INIS)

    Beblo, K.; Wirth, R.; Huber, H.; Douki, T.; Schmalz, G.; Rachel, R.

    2011-01-01

    In this study, we investigated the ability of several (hyper-) thermophilic Archaea and phylo-genetically deep-branching thermophilic Bacteria to survive high fluences of monochromatic UV-C (254 nm) and high doses of ionizing radiation, respectively. Nine out of fourteen tested microorganisms showed a surprisingly high tolerance against ionizing radiation, and two species (Aquifex pyrophilus and Ignicoccus hospitalis) were even able to survive 20 kGy. Therefore, these species had a comparable survivability after exposure to ionizing radiation such as Deinococcus radiodurans. In contrast, there was nearly no difference in survival of the tested strains after exposure to UV-C under anoxic conditions. If the cells had been dried in advance of UV-C irradiation, they were more sensitive to UV-C radiation compared with cells irradiated in liquid suspension; this effect could be reversed by the addition of protective material like sulfidic ores before irradiation. By exposure to UV-C, photoproducts were formed in the DNA of irradiated Archaea and Bacteria. The distribution of the main photoproducts was species specific, but the amount of the photoproducts was only partly dependent on the applied fluence. Overall, our results show that tolerance to radiation seems to be a common phenomenon among thermophilic and hyper-thermophilic microorganisms. (authors)

  11. A UVC Device for Intra-luminal Disinfection of Catheters: In Vitro Tests on Soft Polymer Tubes Contaminated with Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli and Candida albicans

    DEFF Research Database (Denmark)

    Bak, Jimmy; Begovic, Tanja; Bjarnsholt, Thomas

    2011-01-01

    light is possible. In this paper we present dose-response results using a newly developed UVC disinfection device, which can be connected to a Luer catheter hub. The device was tested on soft polymer tubes contaminated with a pallet of microorganisms, including Candida albicans, Staphylococcus aureus...

  12. Perception of volatiles produced by UVC-irradiated plants alters the response to viral infection in naïve neighboring plants.

    Science.gov (United States)

    Yao, Youli; Danna, Cristian H; Ausubel, Frederick M; Kovalchuk, Igor

    2012-07-01

    Interplant communication of stress via volatile signals is a well-known phenomenon. It has been shown that plants undergoing stress caused by pathogenic bacteria or insects generate volatile signals that elicit defense response in neighboring naïve plants. Similarly, we have recently shown that naïve plants sharing the same gaseous environment with UVC-exposed plants exhibit similar changes in genome instability as UVC-exposed plants. We found that methyl salicylate (MeSA) and methyl jasmonate (MeJA) serve as volatile signals communicating genome instability (as measured by an increase in the homologous recombination frequency). UVC-exposed plants produce high levels of MeSA and MeJA, a response that is missing in an npr1 mutant. Concomitantly, npr1 mutants are impaired in communicating the signal leading to genome instability, presumably because this mutant does not develop new necrotic lesion after UVC irradiation as observed in wt plants. To analyze the potential biological significance of such plant-plant communication, we have now determined whether bystander plants that receive volatile signals from UVC-irradiated plants, become more resistant to UVC irradiation or infection with oilseed rape mosaic virus (ORMV). Specifically, we analyzed the number of UVC-elicited necrotic lesions, the level of anthocyanin pigments, and the mRNA levels corresponding to ORMV coat protein and the NPR1-regulated pathogenesis-related protein PR1 in the irradiated or virus-infected bystander plants that have been previously exposed to volatiles produced by UVC-irradiated plants. These experiments showed that the bystander plants responded similarly to control plants following UVC irradiation. Interestingly, however, the bystander plants appeared to be more susceptible to ORMV infection, even though PR1 mRNA levels in systemic tissue were significantly higher than in the control plants, which indicates that bystander plants could be primed to strongly respond to bacterial

  13. Effect of UV-C radiation and hot water on the calcium content and postharvest quality of apples

    International Nuclear Information System (INIS)

    Hemmaty, S.; Moallemi, N.; Naseri, L.

    2007-01-01

    To increase the storage shelf life of 'Red Delicious' and 'Golden Delicious' apples they were treated with UV-C irradiation at doses of 0, 5 and 15 min irradiation at 1.435 x 10 -4 W/square cm - and with hot water containing 4% CaCl 2 at four levels (control, dipping at 25 deg C for 10 min, dipping at 38 deg C for 5 min and dipping in 54 deg C for 1 min) in a factorial design with 4 replicates. The results showed that UV-C irradiation and dipping of fruit in hot water increased the storage life and improved fruit quality factors in 'Red Delicious' and 'Golden Delicious' apples at the end of cold storage. Both UV-C and hot water treatments decreased pH and total soluble solids/titratable acids ratio and increased fruit titratable acids and firmness. UV-C and hot water treatment increased fruit Ca content during storage. The results showed that UV-C and hot water treatment can retard fruit ripening and maintain fruit quality in cold storage. These treatments can also increase Ca concentration of fruit flesh and thus increase the nutritional value of the apples. (author) [es

  14. Combination of UV-C treatment and Metschnikowia pulcherrimas for controlling Alternaria rot in postharvest winter jujube fruit.

    Science.gov (United States)

    Guo, Dongqi; Zhu, Lixia; Hou, Xujie

    2015-01-01

    The potential of using antagonistic yeast Metschnikowia pulcherrimas alone or in combination with ultraviolet-C (UV-C) treatment for controlling Alternaria rot of winter jujube, and its effects on postharvest quality of fruit was investigated. The results showed that spore germination of Alternaria alternata was significantly inhibited by each of the 3 doses (1, 5, and 10 kJ m(-2) ) in vitro. In vivo, UV-C treatment (5 kJ m(-2) ) or antagonist yeast was capable of reducing the percentage of infected wounds and lesion diameter in artificially inoculated jujube fruits, however, in fruit treated with combination of UV-C treatment and M. pulcherrima, the percentage of infected wounds and lesion diameter was only 16.0% and 0.60 cm, respectively. The decay incidence on winter jujube fruits treated with the combination of UV-C treatment and M. pulcherrima was 23% after storage at 0 ± 1 °C for 45 d followed by 22 °C for 7 d. None of the treatments impaired quality parameters of jujube fruit. Thus, the combination of UV-C radiation and M. pulcherrima could be an alternative to synthetic fungicides for controlling postharvest Alternaria rot of winter jujube. © 2014 Institute of Food Technologists®

  15. Pre-harvest UV-C irradiation triggers VOCs accumulation with alteration of antioxidant enzymes and phytohormones in strawberry leaves.

    Science.gov (United States)

    Xu, Yanqun; Luo, Zisheng; Charles, Marie Thérèse; Rolland, Daniel; Roussel, Dominique

    2017-11-01

    Recent studies have highlighted the biological and physiological effects of pre-harvest ultraviolet (UV)-C treatment on growing plants. However, little is known about the involvement of volatile organic compounds (VOCs) and their response to this treatment. In this study, strawberry plants were exposed to three different doses of UV-C radiation for seven weeks (a low dose: 9.6kJm -2 ; a medium dose: 15kJm -2 ; and a high-dose: 29.4kJm -2 ). Changes in VOC profiles were investigated and an attempt was made to identify factors that may be involved in the regulation of these alterations. Principle compounds analysis revealed that VOC profiles of UV-C treated samples were significantly altered with 26 VOCs being the major contributors to segregation. Among them, 18 fatty acid-derived VOCs accumulated in plants that received high and medium dose of UV-C treatments with higher lipoxygenase and alcohol dehydrogenase activities. In treated samples, the activity of the antioxidant enzymes catalase and peroxidase was inhibited, resulting in a reduced antioxidant capacity and higher lipid peroxidation. Simultaneously, jasmonic acid level was 74% higher in the high-dose group while abscisic acid content was more than 12% lower in both the medium and high-dose UV-C treated samples. These results indicated that pre-harvest UV-C treatment stimulated the biosynthesis of fatty acid-derived VOCs in strawberry leaf tissue by upregulating the activity of enzymes of the LOX biosynthetic pathway and downregulating antioxidant enzyme activities. It is further suggested that the mechanisms underlying fatty acid-derived VOCs biosynthesis in UV-C treated strawberry leaves are associated with UV-C-induced changes in phytohormone profiles. Crown Copyright © 2017. Published by Elsevier GmbH. All rights reserved.

  16. Improvement of the Antioxidant Properties and Postharvest Life of Three Exotic Andean Fruits by UV-C Treatment

    Directory of Open Access Journals (Sweden)

    María J. Andrade-Cuvi

    2017-01-01

    Full Text Available Three Andean fruits naranjilla (Solanum quitoense Lam., uvilla (Physalis peruviana L., and mortiño (Vaccinium floribundum Kunth were subjected to prestorage UV-C treatments (0, 8, or 12.5 kJ m−2 and evaluated weekly to select the most suitable dose for fruit quality maintenance during storage (21 days at 6°C. The highest dose retains quality through lower deterioration index for all three fruits and was selected to further analyze the effects on physicochemical and antioxidant properties during storage. UV-C exposure delayed softening in naranjilla and increased soluble solid content in uvilla. UV-C also improved the maintenance of antioxidant capacity (AC in mortiño and uvilla. Overall, results indicate that short prestorage UV-C exposure may be an effective nonchemical approach to supplement low temperature storage, maintain quality, and extend the postharvest life of Andean naranjilla, uvilla, and mortiño fruit.

  17. Influence of occupational exposure to pesticides on the level of DNA damage induced in human lymphocytes (Polish group) by UV-C and X-rays

    International Nuclear Information System (INIS)

    Dyga, W.; Drag, Z.; Cebulska-Wasilewska, A.

    2002-01-01

    The aim of this study was to find out whether occupational exposure to pesticides might affect the individual susceptibility of various donors to the induction of DNA damage by genotoxic agents (UV-C, X-rays) and the efficiency of cellular repair. Previously cryo preserved lymphocytes were defrosted, and DNA damage in the lymphocytes prior to any in vitro studies was investigated with the application of the Comet assay. In order to evaluate the susceptibilities of human lymphocytes to genotoxic agents and the variability of repair capacities, the DNA migrations were estimated immediately after exposure to UV-C light or X-rays and after two hours. On average, the DNA damage detected in untreated lymphocytes was significantly higher in the group exposed to pesticides than in reference group. UV-C treated lymphocytes from group exposed to pesticides shows a greater statistically significant level of DNA migration compared to the reference group, detected after 2 hours incubation in the absence of PHA. Significantly lower responses to X-rays and higher levels of residual DNA damage were detected in the lymphocytes of donors from the group exposed to pesticides compared with the reference group. In conclusion, our results suggest that occupational exposure to pesticides influences the level of induced DNA damage, and the cellular capabilities of repair. (author)

  18. Effect of coagulation on treatment of municipal wastewater reverse osmosis concentrate by UVC/H{sub 2}O{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Umar, Muhammad; Roddick, Felicity, E-mail: felicity.roddick@rmit.edu.au; Fan, Linhua

    2014-02-15

    Highlights: • Alum coagulation is an effective pre-treatment for UVC/H{sub 2}O{sub 2} treatment of high salinity ROC. • Comparable DOC in samples but different coagulation success due to different nature of organics. • Comparable mineralization obtained for two different ROCs with UVC/H{sub 2}O{sub 2} only treatment. • UVC/H{sub 2}O{sub 2} treatment led to increased biodegradability with and without coagulation. • Significant reduction in energy consumption obtained after pre- and biological post-treatment. -- Abstract: Disposal of reverse osmosis concentrate (ROC) is a growing concern due to potential health and ecological risks. Alum coagulation was investigated as pre-treatment for the UVC/H{sub 2}O{sub 2} treatment of two high salinity ROC samples (ROC A and B) of comparable organic and inorganic content. Coagulation removed a greater fraction of the organic content for ROC B (29%) than ROC A (16%) which correlated well with the reductions of colour and A{sub 254}. Although the total reductions after 60 min UVC/H{sub 2}O{sub 2} treatment with and without coagulation were comparable, large differences in the trends of reduction were observed which were attributed to the different nature of the organic content (humic-like) of the samples as indicated by the LC-OCD analyses and different initial (5% and 16%) biodegradability. Coagulation and UVC/H{sub 2}O{sub 2} treatment preferentially removed humic-like compounds which resulted in low reaction rates after UVC/H{sub 2}O{sub 2} treatment of the coagulated samples. The improvement in biodegradability was greater (2–3-fold) during UVC/H{sub 2}O{sub 2} treatment of the pre-treated samples than without pre-treatment. The target DOC residual (≤15 mg/L) was obtained after 30 and 20 min irradiation of pre-treated ROC A and ROC B with downstream biological treatment, corresponding to reductions of 55% and 62%, respectively.

  19. Guest Room Lighting at the Hilton Columbus Downtown

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-06-30

    At the Hilton Columbus Downtown hotel in Ohio, DOE's Better Buildings Alliance conducted a demonstration of Next Generation Luminaires-winning downlights installed in all guest rooms and suites prior to the hotel's 2012 opening. After a post-occupancy assessment, the LED downlights not only provided the aesthetic appearance and dimming functionality desired, but also provided 50% energy savings relative to a comparable CFL downlight and enabled the lighting power to be more than 20% below that allowed by code. This document is a summary case study of the report.

  20. Stress-Induced Sleep After Exposure to Ultraviolet Light Is Promoted by p53 in Caenorhabditis elegans.

    Science.gov (United States)

    DeBardeleben, Hilary K; Lopes, Lindsey E; Nessel, Mark P; Raizen, David M

    2017-10-01

    Stress-induced sleep (SIS) in Caenorhabditis elegans is important for restoration of cellular homeostasis and is a useful model to study the function and regulation of sleep. SIS is triggered when epidermal growth factor (EGF) activates the ALA neuron, which then releases neuropeptides to promote sleep. To further understand this behavior, we established a new model of SIS using irradiation by ultraviolet C (UVC) light. While UVC irradiation requires ALA signaling and leads to a sleep state similar to that induced by heat and other stressors, it does not induce the proteostatic stress seen with heat exposure. Based on the known genotoxic effects of UVC irradiation, we tested two genes, atl-1 and cep-1 , which encode proteins that act in the DNA damage response pathway. Loss-of-function mutants of atl-1 had no defect in UVC-induced SIS but a partial loss-of-function mutant of cep-1 , gk138 , had decreased movement quiescence following UVC irradiation. Germline ablation experiments and tissue-specific RNA interference experiments showed that cep-1 is required somatically in neurons for its effect on SIS. The cep-1 ( gk138 ) mutant suppressed body movement quiescence controlled by EGF, indicating that CEP-1 acts downstream or in parallel to ALA activation to promote quiescence in response to ultraviolet light. Copyright © 2017 by the Genetics Society of America.

  1. New airborne pathogen transport model for upper-room UVGI spaces conditioned by chilled ceiling and mixed displacement ventilation: Enhancing air quality and energy performance

    International Nuclear Information System (INIS)

    Kanaan, Mohamad; Ghaddar, Nesreen; Ghali, Kamel; Araj, Georges

    2014-01-01

    Highlights: • A model of bacteria transport is developed in CC/DV conditioned spaces with UVGI. • The model identifies buoyant, partially mixed, and fully mixed transport zones. • The predicted bacteria concentration agreed well with CFD results. • The higher the supply flow rate, the more restrictive is return air mixing ratio. • Upper-room UVGI results in higher return mixing and 33% in energy savings. - Abstract: The maximum allowable return air ratio in chilled ceiling (CC) and mixed displacement ventilation (DV) system for good air quality is regulated by acceptable levels of CO 2 concentration not to exceed 700 ppm and airborne bacterial count to satisfy World Health Organization (WHO) requirement for bacterial count not to exceed 500 CFU/m 3 . Since the CC/DV system relies on buoyancy effects for driving the contaminated air upwards, infectious particles will recirculate in the upper zone allowing effective utilization of upper-room ultraviolet germicidal irradiation (UVGI) to clean return air. The aim of this work is to develop a new airborne bacteria transport plume-multi-layer zonal model at low computational cost to predict bacteria concentration distribution in mixed CC/DV conditioned room without and with upper-room UVGI installed. The results of the simplified model were compared with layer-averaged concentration predictions of a detailed and experimentally-validated 3-D computational fluid dynamics (CFD) model. The comparison showed good agreement between bacteria transport model results and CFD predictions of room air bacteria concentration with maximum error of ±10.4 CFU/m 3 in exhaust air. The simplified model captured the vertical bacteria concentration distribution in room air as well as the locking effect of highest concentration happening at the stratification level. The developed bacteria transport model was used in a case study to determine the return air mixing ratio that minimizes energy consumption and maintains acceptable IAQ

  2. A homozygous recA mutant of Synechocystis PCC6803: construction strategy and characteristics eliciting a novel RecA independent UVC resistance in dark.

    Science.gov (United States)

    Minda, Renu; Ramchandani, Jyoti; Joshi, Vasudha P; Bhattacharjee, Swapan Kumar

    2005-12-01

    We report here the construction of a homozygous recA460::cam insertion mutant of Synechocystis sp. PCC 6803 that may be useful for plant molecular genetics by providing a plant like host free of interference from homologous recombination. The homozygous recA460::cam mutant is highly sensitive to UVC under both photoreactivating and non-photoreactivating conditions compared to the wild type (WT). The liquid culture of the mutant growing in approximately 800 lx accumulates nonviable cells to the tune of 86% as estimated by colony counts on plates incubated at the same temperature and light intensity. The generation time of recA mutant in standard light intensity (2,500 lx) increases to 50 h compared to 28 h in lower light intensity (approximately 800 lx) that was used for selection, thus explaining the earlier failures to obtain a homozygous recA mutant. The WT, in contrast, grows at faster rate (23 h generation time) in standard light intensity compared to that at approximately 800 lx (26 h). The Synechocystis RecA protein supports homologous recombination during conjugation in recA (-) mutant of Escherichia coli, but not the SOS response as measured by UV sensitivity. It is suggested that using this homozygous recA460::cam mutant, investigations can now be extended to dissect the network of DNA repair pathways involved in housekeeping activities that may be more active in cyanobacteria than in heterotrophs. Using this mutant for the first time we provide a genetic evidence of a mechanism independent of RecA that causes enhanced UVC resistance on light to dark transition.

  3. Água aquecida e radiação UV-C no controle pós-colheita de Cryptosporiopsis perennans em maçãs Heated water and UV-C radiation to postharvest control of Cryptosporiopsis perennans on apples

    Directory of Open Access Journals (Sweden)

    Vinícius Adão Bartnicki

    2010-02-01

    Full Text Available O objetivo deste trabalho foi avaliar a colonização de Cryptosporiopsis perennans na epiderme de maçãs e a eficiência da aplicação de água aquecida e radiação UV-C no controle desse patógeno. Em maçãs submetidas à inoculação de C. perennans, a colonização de lenticelas e das áreas adjacentes pelo patógeno foi avaliada por microscopia eletrônica de varredura. A sensibilidade dos conídios de C. perennans aos tratamentos foi avaliada em suspensão aquosa, às temperaturas de 28, 45, 50 e 55ºC, por 15 e 30 s, e às doses de radiação UV-C de 0,018, 0,037, 0,075, 0,150, 0,375, 0,750, 1,500 e 3,000 kJ m-2. Em maçãs submetidas à inoculação de C. perennans, foram avaliados os efeitos de 0,375, 0,750 e 1,500 kJ m-2 de radiação UV-C e da aspersão de água aquecida à 50ºC, por 15 e 30 s no controle do patógeno. O fungo produziu abundante micélio e conídios nas lenticelas e nas áreas adjacentes, na epiderme das maçãs. A água aquecida a 50ºC por 15 s e à dose de radiação de UV-C de 0,750 kJ m-2 reduzem em mais de 99% a sobrevivência de conídios. A aspersão de água aquecida a 50ºC por 15 s e à dose de radiação de UV-C de 0,375 kJ m-2, controlam C. perennans em maçãs.The objective of this work was to assess the colonization of Cryptosporiopsis perennans in the epidermis of apples and the efficiency of heated water and UV-C radiation application to control this pathogen. In apples inoculated with C. perennans, the colonization of lenticels and adjacent areas by the pathogen was observed by electronic scanning microscopy. The sensitivity of C. perennans conidia was evaluated in aqueous suspension, at temperatures of 28, 45, 50 and 55ºC for 15 and 30 s, and at UV-C radiation doses of 0.018, 0.037, 0.075, 0.150, 0.375, 0.750, 1.500 and 3.000 kJ m-2. The effects of UV-C radiation doses at 0.375, 0.750 and 1.500 kJ m-2 and heated water at 50ºC, sprayed during 15 and 30 s were evaluated for controlling C

  4. Toward hydrogen detection at room temperature with printed ZnO nanoceramics films activated with halogen lighting

    Science.gov (United States)

    Nguyen, Van Son; Jubera, Véronique; Garcia, Alain; Debéda, Hélène

    2015-12-01

    Though semiconducting properties of ZnO have been extensively investigated under hazardous gases, research is still necessary for low-cost sensors working at room temperature. Study of printed ZnO nanopowders-based sensors has been undertaken for hydrogen detection. A ZnO paste made with commercial nanopowders is deposited onto interdigitated Pt electrodes and sintered at 400 °C. The ZnO layer structure and morphology are first examined by XRD, SEM, AFM and emission/excitation spectra prior to the study of the effect of UV-light on the electrical conduction of the semiconductor oxide. The response to hydrogen exposure is subsequently examined, showing that low UV-light provided by halogen lighting enhances the gas response and allows detection at room temperature with gas responses similar to those obtained in dark conditions at 150 °C. A gas response of 44% (relative change in current) under 300 ppm is obtained at room temperature. Moreover, it is demonstrated that very low UV-light power (15 μW/mm2) provided by the halogen lamp is sufficient to give sensitivities as high as those for much higher powers obtained with a UV LED (7.7 mW/mm2). These results are comparable to those obtained by others for 1D or 2D ZnO nanostructures working at room temperature or at temperatures up to 250 °C.

  5. The Effect of UVC Irradiation on the Mechanical Properties of Chitosan Membrane in Sterilization Process

    Science.gov (United States)

    Rupiasih, N. N.; Sumadiyasa, M.; Putra, I. K.

    2018-04-01

    The present study, we report about the effect of UVC irradiation on the mechanical properties of chitosan membrane in the sterilization process. The membrane used was chitosan membrane 2% which prepared by a casting method using chitosan as matrix and acetic acid 1% as a solvent. The UVC source used was germicidal ultraviolet (UVG) which widely used for sterilization purposes. Variation doses were done by the varying time of irradiation, e.g. 5 min, 15 min, 30 min, and 60 min. Those samples are named as S1, S2, S3, and S4, respectively. Chitosan membrane before irradiation namely S0 also used for comparative study. The effect of UVC irradiation on the mechanical properties of membranes has been examined by different techniques including FTIR, DMA, and the water uptake capability. The results showed that ultimate tensile strength (UTS) and moduli of elasticity (E) were increased by increasing the irradiation time. From FTIR analysis obtained that no new molecules were formed in irradiated membranes. The water uptakes capability of the membranes after irradiation was smaller compared with before irradiation, and among the irradiated membranes, the water uptake capabilities were increased by increasing the exposure time. These observations suggested that more care should be taken during the sterilization process and outdoor used of the membrane. The other side, the UVC irradiation can improve the mechanical properties of the membranes.

  6. Evaluate Influence to Space Lighting Intensity in Main Control Room of RSG-GAS

    International Nuclear Information System (INIS)

    Teguh-Sulistyo; Yuyut-S-M; Yahya; Adin S

    2006-01-01

    Have been done by an activity evaluate factor depreciation influence to light source in Main Control Room (RKU). This Factor Depreciation is resulted from by defilement of effect of dirt, duration of light source utilized, way of installation, and others. Method used by perceives directly at light source, determining measurement dot in space RKU, measurement by using meter lux equipment and group storey; level depreciation of light source become light depreciation, and heavy. Than measurement result that lighting intensity in space RKU experience of decrease of equal to 1.5 %. After by stage; steps overcome the factor depreciation, result of measurement repeat obtained by decrease of equal to 0.87 %. Thereby the lighting intensity in space RKU becomes better. (author)

  7. Enhanced degradation of paracetamol by UV-C supported photo-Fenton process over Fenton oxidation.

    Science.gov (United States)

    Manu, B; Mahamood, S

    2011-01-01

    For the treatment of paracetamol in water, the UV-C Fenton oxidation process and classic Fenton oxidation have been found to be the most effective. Paracetamol reduction and chemical oxygen demand (COD) removal are measured as the objective functions to be maximized. The experimental conditions of the degradation of paracetamol are optimized by the Fenton process. Influent pH 3, initial H(2)O(2) dosage 60 mg/L, [H(2)O(2)]/[Fe(2+)] ratio 60 : 1 are the optimum conditions observed for 20 mg/L initial paracetamol concentration. At the optimum conditions, for 20 mg/L of initial paracetamol concentration, 82% paracetamol reduction and 68% COD removal by Fenton oxidation, and 91% paracetamol reduction and 82% COD removal by UV-C Fenton process are observed in a 120 min reaction time. By HPLC analysis, 100% removal of paracetamol is observed at the above optimum conditions for the Fenton process in 240 min and for the UV-C photo-Fenton process in 120 min. The methods are effective and they may be used in the paracetamol industry.

  8. Effect of UVC Radiation on Hydrated and Desiccated Cultures of Slightly Halophilic and Non-Halophilic Methanogenic Archaea: Implications for Life on Mars.

    Science.gov (United States)

    Sinha, Navita; Kral, Timothy A

    2018-05-12

    Methanogens have been considered models for life on Mars for many years. In order to survive any exposure at the surface of Mars, methanogens would have to endure Martian UVC radiation. In this research, we irradiated hydrated and desiccated cultures of slightly halophilic Methanococcus maripaludis and non-halophilic Methanobacterium formicicum for various time intervals with UVC (254 nm) radiation. The survivability of the methanogens was determined by measuring methane concentrations in the headspace gas samples of culture tubes after re-inoculation of the methanogens into their growth-supporting media following exposure to UVC radiation. Hydrated M. maripaludis survived 24 h of UVC exposure, while in a desiccated condition they endured for 16 h. M. formicicum also survived UVC radiation for 24 h in a liquid state; however, in a desiccated condition, the survivability of M. formicicum was only 12 h. Some of the components of the growth media could have served as shielding agents that protected cells from damage caused by exposure to ultraviolet radiation. Overall, these results suggest that limited exposure (12⁻24 h) to UVC radiation on the surface of Mars would not necessarily be a limiting factor for the survivability of M. maripaludis and M. formicicum .

  9. Room-temperature spin-polarized organic light-emitting diodes with a single ferromagnetic electrode

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Baofu, E-mail: b.ding@ecu.edu.au; Alameh, Kamal, E-mail: k.alameh@ecu.edu.au [Electron Science Research Institute, Edith Cowan University, 270 Joondalup Drive, Joondalup WA 6027 Australia (Australia); Song, Qunliang [Institute for Clean Energy and Advanced Materials, Southwest University, Chongqing 400715 (China)

    2014-05-19

    In this paper, we demonstrate the concept of a room-temperature spin-polarized organic light-emitting diode (Spin-OLED) structure based on (i) the deposition of an ultra-thin p-type organic buffer layer on the surface of the ferromagnetic electrode of the Spin-OLED and (ii) the use of oxygen plasma treatment to modify the surface of that electrode. Experimental results demonstrate that the brightness of the developed Spin-OLED can be increased by 110% and that a magneto-electroluminescence of 12% can be attained for a 150 mT in-plane magnetic field, at room temperature. This is attributed to enhanced hole and room-temperature spin-polarized injection from the ferromagnetic electrode, respectively.

  10. Arbitrary helicity control of circularly polarized light from lateral-type spin-polarized light-emitting diodes at room temperature

    Science.gov (United States)

    Nishizawa, Nozomi; Aoyama, Masaki; Roca, Ronel C.; Nishibayashi, Kazuhiro; Munekata, Hiro

    2018-05-01

    We demonstrate arbitrary helicity control of circularly polarized light (CPL) emitted at room temperature from the cleaved side facet of a lateral-type spin-polarized light-emitting diode (spin-LED) with two ferromagnetic electrodes in an antiparallel magnetization configuration. Driving alternate currents through the two electrodes results in polarization switching of CPL with frequencies up to 100 kHz. Furthermore, tuning the current density ratio in the two electrodes enables manipulation of the degree of circular polarization. These results demonstrate arbitrary electrical control of polarization with high speed, which is required for the practical use of lateral-type spin-LEDs as monolithic CPL light sources.

  11. Effect of UV-C radiation and hot water on the calcium content and postharvest quality of apples

    Energy Technology Data Exchange (ETDEWEB)

    Hemmaty, S.; Moallemi, N.; Naseri, L.

    2007-12-15

    To increase the storage shelf life of 'Red Delicious' and 'Golden Delicious' apples they were treated with UV-C irradiation at doses of 0, 5 and 15 min irradiation at 1.435 x 10{sup -4} W/square cm{sup -} and with hot water containing 4% CaCl{sub 2} at four levels (control, dipping at 25 deg C for 10 min, dipping at 38 deg C for 5 min and dipping in 54 deg C for 1 min) in a factorial design with 4 replicates. The results showed that UV-C irradiation and dipping of fruit in hot water increased the storage life and improved fruit quality factors in 'Red Delicious' and 'Golden Delicious' apples at the end of cold storage. Both UV-C and hot water treatments decreased pH and total soluble solids/titratable acids ratio and increased fruit titratable acids and firmness. UV-C and hot water treatment increased fruit Ca content during storage. The results showed that UV-C and hot water treatment can retard fruit ripening and maintain fruit quality in cold storage. These treatments can also increase Ca concentration of fruit flesh and thus increase the nutritional value of the apples. (author) [Spanish] Con el fin de prolongar el periodo de vida útil durante la conservación frigorífica de manzanas ‘Red Delicious’ y ‘Golden Delicious’, éstas se trataron con radiación UV-C en tres dosis (0, 5 y 15 min de irradiación a 1,435 × 10{sup -4} W cm{sup -2}) y agua caliente con CaCl{sub 2} al 4% en cuatro niveles (control 0, inmersión a 25°C 10 min, 38°C 5 min ó 54°C 1 min), en un diseño factorial con 4 repeticiones por tratamiento. La irradiación con UV-C y la inmersión de los frutos en agua caliente permitió alargar el periodo de conservación y mejoró la calidad de manzanas ‘Red Delicious’ y ‘Golden Delicious’ tras el almacenamiento en frío. Ambos tratamientos aumentaron la acidez titulable y la firmeza de los frutos, también disminuyeron el pH y la relación sólidos solubles/acidez. El tratamiento con UV-C y agua caliente incrementó el contenido

  12. Inactivation of avirulent Yersinia pestis on food and food contact surfaces by ultraviolet light and freezing.

    Science.gov (United States)

    Sommers, Christopher H; Sheen, Shiowshuh

    2015-09-01

    Yersinia pestis, the causative agent of plague, can occasionally be contracted as a naso-pharyngeal or gastrointestinal illness through consumption of contaminated meat. In this study, the use of 254 nm ultraviolet light (UV-C) to inactivate a multi-isolate cocktail of avirulent Y. pestis on food and food contact surfaces was investigated. When a commercial UV-C conveyor was used (5 mW/cm(2)/s) 0.5 J/cm(2) inactivated >7 log of the Y. pestis cocktail on agar plates. At 0.5 J/cm(2), UV-C inactivated ca. 4 log of Y. pestis in beef, chicken, and catfish, exudates inoculated onto high density polypropylene or polyethylene, and stainless steel coupons, and >6 log was eliminated at 1 J/cm(2). Approximately 1 log was inactivated on chicken breast, beef steak, and catfish fillet surfaces at a UV-C dose of 1 J/cm(2). UV-C treatment prior to freezing of the foods did not increase the inactivation of Y. pestis over freezing alone. These results indicate that routine use of UV-C during food processing would provide workers and consumers some protection against Y. pestis. Published by Elsevier Ltd.

  13. Cytotoxicity of ZnO NPs towards fresh water algae Scenedesmus obliquus at low exposure concentrations in UV-C, visible and dark conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bhuvaneshwari, M.; Iswarya, V. [Centre for Nanobiotechnology, VIT University, Vellore 632014 (India); Archanaa, S. [Department of Biotechnology, IIT Madras (India); Madhu, G.M. [Department of Chemical Engineering, M.S. Ramaiah Institute of Technology, Bangalore (India); Kumar, G.K. Suraish [Department of Biotechnology, IIT Madras (India); Nagarajan, R. [Department of Chemical Engineering, IIT Madras (India); Chandrasekaran, N. [Centre for Nanobiotechnology, VIT University, Vellore 632014 (India); Mukherjee, Amitava, E-mail: amit.mookerjea@gmail.com [Centre for Nanobiotechnology, VIT University, Vellore 632014 (India)

    2015-05-15

    Highlights: • The cytotoxicity of ZnO NPs with two hydrodynamic sizes towards freshwater algae. • Size dependent toxicity under UV-C, dark and visible light conditions. • Cytotoxicity principally due to ZnO NPs not the released Zn{sup 2+} ions. • The internalization of ZnO NPs leads to membrane damage and ROS production. - Abstract: Continuous increase in the usage of ZnO nanoparticles in commercial products has exacerbated the risk of release of these particles into the aquatic environment with possible harmful effects on the biota. In the current study, cytotoxic effects of two types of ZnO nanoparticles, having different initial effective diameters in filtered and sterilized lake water medium [487.5 ± 2.55 nm for ZnO-1 NPs and 616.2 ± 38.5 nm for ZnO-2 NPs] were evaluated towards a dominant freshwater algal isolate Scenedesmus obliquus in UV-C, visible and dark conditions at three exposure concentrations: 0.25, 0.5 and 1 mg/L. The toxic effects were found to be strongly dependent on the initial hydrodynamic particle size in the medium, the exposure concentrations and the irradiation conditions. The loss in viability, LDH release and ROS generation were significantly enhanced in the case of the smaller sized ZnO-1 NPs than in the case of ZnO-2 NPs under comparable test conditions. The toxicity of both types of ZnO NPs was considerably elevated under UV-C irradiation in comparison to that in dark and visible light conditions, the effects being more enhanced in case of ZnO-1 NPs. The size dependent dissolution of the ZnO NPs in the test medium and possible toxicity due to the released Zn{sup 2+} ions was also noted. The surface adsorption of the nanoparticles was substantiated by scanning electron microscopy. The internalization/uptake of the NPs by the algal cells was confirmed by fluorescence microscopy, transmission electron microscopy, and elemental analyses.

  14. Cytotoxicity of ZnO NPs towards fresh water algae Scenedesmus obliquus at low exposure concentrations in UV-C, visible and dark conditions

    International Nuclear Information System (INIS)

    Bhuvaneshwari, M.; Iswarya, V.; Archanaa, S.; Madhu, G.M.; Kumar, G.K. Suraish; Nagarajan, R.; Chandrasekaran, N.; Mukherjee, Amitava

    2015-01-01

    Highlights: • The cytotoxicity of ZnO NPs with two hydrodynamic sizes towards freshwater algae. • Size dependent toxicity under UV-C, dark and visible light conditions. • Cytotoxicity principally due to ZnO NPs not the released Zn 2+ ions. • The internalization of ZnO NPs leads to membrane damage and ROS production. - Abstract: Continuous increase in the usage of ZnO nanoparticles in commercial products has exacerbated the risk of release of these particles into the aquatic environment with possible harmful effects on the biota. In the current study, cytotoxic effects of two types of ZnO nanoparticles, having different initial effective diameters in filtered and sterilized lake water medium [487.5 ± 2.55 nm for ZnO-1 NPs and 616.2 ± 38.5 nm for ZnO-2 NPs] were evaluated towards a dominant freshwater algal isolate Scenedesmus obliquus in UV-C, visible and dark conditions at three exposure concentrations: 0.25, 0.5 and 1 mg/L. The toxic effects were found to be strongly dependent on the initial hydrodynamic particle size in the medium, the exposure concentrations and the irradiation conditions. The loss in viability, LDH release and ROS generation were significantly enhanced in the case of the smaller sized ZnO-1 NPs than in the case of ZnO-2 NPs under comparable test conditions. The toxicity of both types of ZnO NPs was considerably elevated under UV-C irradiation in comparison to that in dark and visible light conditions, the effects being more enhanced in case of ZnO-1 NPs. The size dependent dissolution of the ZnO NPs in the test medium and possible toxicity due to the released Zn 2+ ions was also noted. The surface adsorption of the nanoparticles was substantiated by scanning electron microscopy. The internalization/uptake of the NPs by the algal cells was confirmed by fluorescence microscopy, transmission electron microscopy, and elemental analyses

  15. Microbial Safety and Shelf Life of UV-C Treated Freshly Squeezed White Grape Juice.

    Science.gov (United States)

    Unluturk, Sevcan; Atilgan, Mehmet R

    2015-08-01

    The effects of UV-C irradiation on the inactivation of Escherichia coli K-12 (ATCC 25253), a surrogate of E. coli O157:H7, and on the shelf life of freshly squeezed turbid white grape juice (FSWGJ) were investigated. FSWGJ samples were processed at 0.90 mL/s for 32 min by circulating 8 times in an annular flow UV system. The UV exposure time was 244 s per cycle. The population of E. coli K-12 was reduced by 5.34 log cycles after exposure to a total UV dosage of 9.92 J/cm(2) (1.24 J/cm(2) per cycle) at 0.90 mL/s flow rate. The microbial shelf life of UV-C treated FSWGJ was extended up to 14 d at 4 °C. UV exposure was not found to alter pH, total soluble solid, and titratable acidity of juice. There was a significant effect (P shelf life of FSWGJ was doubled after UV-C treatment, whereas the quality of juice was adversely affected similarly observed in the control samples. © 2015 Institute of Food Technologists®

  16. Comparative studies on the lethal, mutagenic, and recombinogenic effects of ultraviolet -A, -B, -C, and visible light with and without 8-methoxypsoralen in Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Mondon, P.; Shahin, M.M.

    1992-01-01

    Genetic effects of UV-A, UV-B, UV-C and the combination of 8-methoxypsoralen (8-MOP) with UV-A or visible light were studied in the haploid strain XV185-14C and diploid strain D5 of Saccharomyces cerevisiae. The induction of his + , lys + , and hom + reverse mutations was measured in strain XV185-14C. In strain D5 we measured the induction of genetically altered colonies, particularly twin spot colonies arising from a mitotic crossing-over. UV-C and UV-B induced point mutations at the three loci in the haploid strain and mitotic crossing-over and other genetic alterations in the diploid strain. UV-C was more mutagenic and recombinogenic than UV-B. UV-A or visible light alone did not induce genotoxic effects at the doses tested. However, UV-A plus 8-MOP produced lethal and mutagenic effects in the haploid strain XV185-14C, although mutagenic activity was less than that of UV-B. Visible light plus 8-MOP also induced genotoxic effects in strain XV185-14C. In the diploid strain D5, UV-A plus 8-MOP induced a higher frequency of genetic alterations than UV-B at comparative doses. Visible light plus 8-MOP was also genetically active in strain D5. The haploid strain was more sensitive to the lethal effects of UV-C, UV-B, UV-A, and impure visible light plus 8-MOP than the diploid strain. (Author)

  17. The effect of UV-C pasteurization on bacteriostatic properties and immunological proteins of donor human milk.

    Science.gov (United States)

    Christen, Lukas; Lai, Ching Tat; Hartmann, Ben; Hartmann, Peter E; Geddes, Donna T

    2013-01-01

    Human milk possesses bacteriostatic properties, largely due to the presence of immunological proteins. Heat treatments such as Holder pasteurization reduce the concentration of immunological proteins in human milk and consequently increase the bacterial growth rate. This study investigated the bacterial growth rate and the immunological protein concentration of ultraviolet (UV-C) irradiated, Holder pasteurized and untreated human milk. Samples (n=10) of untreated, Holder pasteurized and UV-C irradiated human milk were inoculated with E. coli and S. aureus and the growth rate over 2 hours incubation time at 37°C was observed. Additionally, the concentration of sIgA, lactoferrin and lysozyme of untreated and treated human milk was analyzed. The bacterial growth rate of untreated and UV-C irradiated human milk was not significantly different. The bacterial growth rate of Holder pasteurized human milk was double compared to untreated human milk (ppasteurization, resulting in bacteriostatic properties similar to those of untreated human milk.

  18. Upper Bound on the Hadronic Light-By-Light Contribution to the Muon g-2

    International Nuclear Information System (INIS)

    Erler, Jens; Sanchez, Genaro Toledo

    2006-01-01

    There are indications that hadronic loops in some electroweak observables are almost saturated by parton level effects. Taking this as the hypothesis for this work, we propose a genuine parton level estimate of the hadronic light-by-light contribution to the anomalous magnetic moment of the muon, a μ LBL (had). Our quark mass definitions and values are motivated in detail, and the simplicity of our approach allows for a transparent error estimate. For infinitely heavy quarks our treatment is exact, while for asymptotically small quark masses a μ LBL (had) is overestimated. Interpolating, this suggests quoting an upper bound. We obtain a μ LBL (had) -9 (95% C.L.)

  19. an assessment of ultraviolet radiation components of light emitted ...

    African Journals Online (AJOL)

    Dr

    therefore high for exposure limits of 8 hours for UV-B and UV-C and the 16 minutes for UV-A. The investigation ... has become particularly interesting as the ozone layer ... THEORY. Ultraviolet (UV) light is an electromagnetic radiation with a ...

  20. Signal transduction and HIV transcriptional activation after exposure to ultraviolet light and other DNA-damaging agents

    International Nuclear Information System (INIS)

    Valerie, K.; Laster, W.S.; Luhua Cheng; Kirkham, J.C.; Reavey, Peter; Kuemmerle, N.B.

    1996-01-01

    Short wavelength (254 nm) ultraviolet light (UVC) radiation was much more potent in activating transcription of human immunodeficiency virus 1 (HIV) reporter genes stably integrated into the genomes of human and monkey cells than ionizing radiation (IR) from a 137 Cs source at similarly cytotoxic doses. A similar differential was also observed when c-jun transcription levels were examined. However, these transcription levels do not correlate with activation of nuclear factor (NF)-kB and AP-1 measured by band-shift assays, i.e. both types of radiation produce similar increases in NF-kB and AP-1 activity, suggesting existence of additional levels of regulation during these responses. Because of the well-established involvement of cytoplasmic signaling pathways in the cellular response to tumor necrosis factor-α (TNF-α), UVC, and IR using other types of assays, the role of TNF-α in the UVC response of HIV and c-jun was investigated in our cell system. We demonstrate that UVC and TNF-α activate HIV gene expression in a synergistic fashion, suggesting that it is unlikely that TNF-α is involved in UVC activation of HIV transcription in stably transfected HeLa cells. Moreover, maximum TNF-α stimulation resulted in one order of magnitude lower levels of HIV expression than that observed after UVC exposure. We also observed an additive effect of UVC and TNF-α on c-jun steady-state mRNA levels, suggestive of a partial overlap in activation mechanism of c-jun by UVC and TNF-α; yet these responses are distinct to some extent. Our results indicate that the HIV, and to some extent also the c-jun, transcriptional responses to UVC are not the result of TNF-α stimulation and subsequent downstream cytoplasmic signaling events in HeLa cells. In addition to the new data, this report also summarizes our current views regarding UVC-induced activations of HIV gene expression in stably transfected cells. (Author)

  1. Wide band gap Ga2O3 as efficient UV-C photocatalyst for gas-phase degradation applications.

    Science.gov (United States)

    Jędrzejczyk, Marcin; Zbudniewek, Klaudia; Rynkowski, Jacek; Keller, Valérie; Grams, Jacek; Ruppert, Agnieszka M; Keller, Nicolas

    2017-12-01

    α, β, γ, and δ polymorphs of 4.6-4.8 eV wide band gap Ga 2 O 3 photocatalysts were prepared via a soft chemistry route. Their photocatalytic activity under 254 nm UV-C light in the degradation of gaseous toluene was strongly depending on the polymorph phase. α- and β-Ga 2 O 3 photocatalysts enabled achieving high and stable conversions of toluene with selectivities to CO 2 within the 50-90% range, by contrast to conventional TiO 2 photocatalysts that fully deactivate very rapidly on stream in similar operating conditions with rather no CO 2 production, no matter whether UV-A or UV-C light was used. The highest performances were achieved on the high specific surface area β-Ga 2 O 3 photocatalyst synthesized by adding polyethylene glycol (PEG) as porogen before precipitation, with stable toluene conversion and mineralization rate into CO 2 strongly overcoming those obtained on commercial β-Ga 2 O 3 . They were attributed to favorable physicochemical properties in terms of high specific surface area, small mean crystallite size, good crystallinity, high pore volume with large size mesopore distribution and appropriate surface acidity, and to the possible existence of a double local internal field within Ga 3+ units. In the degradation of hydrogen sulfide, PEG-derived β-Ga 2 O 3 takes advantage from its high specific surface area for storing sulfate, and thus for increasing its resistance to deactivation and the duration at total sulfur removal when compared to other β-Ga 2 O 3 photocatalysts. So, we illustrated the interest of using high surface area β-Ga 2 O 3 in environmental photocatalysis for gas-phase depollution applications.

  2. Persuasive technology based on bodily comfort experiences : the effect of color temperature of room lighting on user motivation to change room temperature

    NARCIS (Netherlands)

    Lu, S.; Ham, J.R.C.; Midden, C.J.H.; MacTavish, T.; Basapur, S.

    2015-01-01

    In this paper we propose a new perspective on persuasive technology: Comfort-Experience-Based Persuasive Technology. We argue that comfort experiences have a dominant influence on people’s (energy consumption) behavior. In the current research, we argue that room lighting can influence

  3. Room-temperature light-emission from Ge quantum dots in photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Xia Jinsong [Advanced Research Laboratories, Musashi Institute of Technolgy, 8-15-1 Todoroki, Setagaya-ku, Tokyo 158-0082 (Japan)], E-mail: jxia@sc.musashi-tech.ac.jp; Nemoto, Koudai; Ikegami, Yuta [Advanced Research Laboratories, Musashi Institute of Technolgy, 8-15-1 Todoroki, Setagaya-ku, Tokyo 158-0082 (Japan); Usami, Noritaka [Institute of Materials Research, Tohoku University, 2-2-1 Katahira, Aoba-ku, Sendai Japan (Japan)], E-mail: usa@imr.tohoku.ac.jp; Nakata, Yasushi [Horiba, Ltd., 1-7-8 Higashi-Kanda, Chiyoda-ku, Tokyo 101-0031 (Japan)], E-mail: yasushi.nakata@horiba.com; Shiraki, Yasuhiro [Advanced Research Laboratories, Musashi Institute of Technolgy, 8-15-1 Todoroki, Setagaya-ku, Tokyo 158-0082 (Japan)

    2008-11-03

    Multiple layers of Ge self-assembled quantum dots were embedded into two-dimensional silicon photonic crystal microcavities fabricated on silicon-on-insulator substrates. Microphotoluminescence was used to study the light-emission characteristic of the Ge quantum dots in the microcavities. Strong resonant room-temperature light-emission was observed in the telecommunication wavelength region. Significant enhancement of the luminescence from Ge dots was obtained due to the resonance in the cavities. Multiple sharp resonant peaks dominated the spectrum, showing strong optical resonance inside the cavity. By changing the lattice constant of photonic crystal structure, the wavelengths of the resonant peaks are tuned in the wide wavelength range from 1.2 to 1.6 {mu}m.

  4. Use of UV-C radiation to disinfect non-critical patient care items: a laboratory assessment of the Nanoclave Cabinet

    Directory of Open Access Journals (Sweden)

    Moore Ginny

    2012-08-01

    Full Text Available Abstract Background The near-patient environment is often heavily contaminated, yet the decontamination of near-patient surfaces and equipment is often poor. The Nanoclave Cabinet produces large amounts of ultraviolet-C (UV-C radiation (53 W/m2 and is designed to rapidly disinfect individual items of clinical equipment. Controlled laboratory studies were conducted to assess its ability to eradicate a range of potential pathogens including Clostridium difficile spores and Adenovirus from different types of surface. Methods Each test surface was inoculated with known levels of vegetative bacteria (106 cfu/cm2, C. difficile spores (102-106 cfu/cm2 or Adenovirus (109 viral genomes, placed in the Nanoclave Cabinet and exposed for up to 6 minutes to the UV-C light source. Survival of bacterial contaminants was determined via conventional cultivation techniques. Degradation of viral DNA was determined via PCR. Results were compared to the number of colonies or level of DNA recovered from non-exposed control surfaces. Experiments were repeated to incorporate organic soils and to compare the efficacy of the Nanoclave Cabinet to that of antimicrobial wipes. Results After exposing 8 common non-critical patient care items to two 30-second UV-C irradiation cycles, bacterial numbers on 40 of 51 target sites were consistently reduced to below detectable levels (≥ 4.7 log10 reduction. Bacterial load was reduced but still persisted on other sites. Objects that proved difficult to disinfect using the Nanoclave Cabinet (e.g. blood pressure cuff were also difficult to disinfect using antimicrobial wipes. The efficacy of the Nanoclave Cabinet was not affected by the presence of organic soils. Clostridium difficile spores were more resistant to UV-C irradiation than vegetative bacteria. However, two 60-second irradiation cycles were sufficient to reduce the number of surface-associated spores from 103 cfu/cm2 to below detectable levels. A 3 log10 reduction in

  5. Heat and ultraviolet light treatment of colostrum and hospital milk: effects on colostrum and hospital milk characteristics and calf health and growth parameters.

    Science.gov (United States)

    Teixeira, A G V; Bicalho, M L S; Machado, V S; Oikonomou, G; Kacar, C; Foditsch, C; Young, R; Knauer, W A; Nydam, D V; Bicalho, R C

    2013-08-01

    The aim of this study was to evaluate the effects of different physical treatments of bovine colostrum and hospital milk on milk bacteriology, immunoglobulin G (IgG) and lactoferrin concentrations, calf serum IgG concentrations and calf health, growth and survivability. Pooled colostrum samples (n=297) were heat treated (HTC; 63°C for 60 min), exposed to ultraviolet light (UVC; 45 J/cm(2)) or untreated ('raw', RC). Hospital milk (n=712) was subjected to high temperature short time pasteurization (HTST; 72°C for 15s), ultraviolet light irradiation (UVH; 45 J/cm(2)) or was untreated. Neonatal Holstein heifer calves (n=875) were randomly enrolled (309 HTC, 285 UVC, 281 RC) and block randomized (by colostrum treatment) into hospital milk treatments HTST (n=449) or UVH (n=426). HTC was more effective than UVC and HTST was more effective than UVH in reducing bacterial counts. IgG and lactoferrin concentrations were significantly lower in HTC and UVC than in RC. Lactoferrin concentrations were significantly lower in HTST than in UVH or untreated hospital milk. There were no significant differences in serum IgG concentrations among calves fed HTC, UVC or RC. Colostrum and hospital milk treatments did not have any significant effect on calf body weight gain, survivability, or frequency of diarrhea or pneumonia. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. The attenuation effect of UVc radiation doses in gram-negative bacteria (Brucella, Yersinia, Escherichia coli)

    International Nuclear Information System (INIS)

    Al-Mariri, A.

    2007-01-01

    The gram-negative bacteria Yersinia enterocolitica sero group O:3 and O:9, and Brucella (Melitensis and abortus) together with Escherichia coli (O:157, DH5alpha-pEt15b), were investigated to evaluate their susceptibility to UV radiation at 254 nm. If the dose of UVc was 18.7 mW/cm2, the time required for inactivation of Y. enterocolitica and E. coli DH5alpha-pEt15b and O:157 was 240s and 360s in the dark and light respectively. Where if the dose was 19.5 mW/cm2, the time required was 60s in the dark and 120s in light respectively. The time required for inactivation of Brucella strains (melitensis and abortus) if the dose was 18.7 mW/cm2 was 240s in both dark and light, whereas it was 120s (dark) and 240s (light) respectively, when the dose was 19.5 mW/cm2. Using E. coli O:157 as control, it appears that Y. enterocolitica sero group O:3 and O:9 and vaccinal strains of Brucella (Rev. 1 and S19) are more sensitive to UV than wild Brucella strains. No relation was found between the sensitivity of Y. enterocolitica to UV and the presence or absence of a pYV+ virulence plasmid. (author)

  7. The attenuation effect of UVc radiation doses in gram-negative bacteria (Brucella, Yersinia, Escherichia coli)

    International Nuclear Information System (INIS)

    Al-Mariri, A.

    2006-06-01

    The gram-negative bacteria Yersinia enterocolitica sero group O:3 and O:9, and Brucella (Melitensis and abortus) together with Escherichia coli (O:157, DH5α-pEt15b), were investigated to evaluate their susceptibility to UV radiation at 254 nm. If the dose of UVc was 18.7 mW/cm 2 , the time required for inactivation of Y. enterocolitica and E. coli DH5α-pEt15b and O:157 was 240s and 360s in the dark and light respectively; where if the dose was 19.5 mW/cm 2 , the time required was 60s in the dark and 120s in light respectively. The time required for inactivation of Brucella strains (melitensis and abortus) if the dose was 18.7 mW/cm 2 was 240s in both dark and light, whereas it was 120s(dark) and 240s (light) respectively, when the dose was 19.5 mW/cm 2 . Using E. coli O:157 as control, it appears that Y. enterocolitica sero group O:3 and O:9 and vaccinal strains of Brucella (Rev. 1 and S19) are more sensitive to UV than wild Brucella strains. No relation was found between the sensitivity of Y. enterocolitica to UV and the presence or absence of a pYV + virulence plasmid. (author)

  8. Ultraviolet radiation (UV-C) on the post harvest control of Colletotrichum gloeosporioides in 'niagara rosada' grapes;Radiacao ultravioleta no controle pos-colheita de Colletotrichum gloeosporides em uva 'niagara rosada'

    Energy Technology Data Exchange (ETDEWEB)

    Cia, Patricia; Sanches, Juliana, E-mail: pcia@iac.sp.gov.b [Instituto Agronomico de Campinas (IAC), Jundiai, SP (Brazil). Centro de Engenharia e Automacao; Benato, Eliane Aparecida; Valentini, Silvia Regina de Toledo; Anjos, Valeria Delgado de Almeida [Instituto de Tecnologia de Alimentos (ITAL), Campinas, SP (Brazil). Grupo de Engenharia e Pos-Colheita; Ponzo, Francine Scolfaro [Instituto Agronomico de Campinas (IAC), SP (Brazil); Terra, Maurilo Monteiro [Instituto Agronomico de Campinas (IAC), SP (Brazil). Centro de Ecofisiologia e Biofisica

    2009-07-01

    Most of the post harvest losses of 'Niagara Rosada' grapes are caused by rot and detached berries. Recently, many researches on alternative methods, such as physical treatments, have been carried out in order to control rots and extend the shelf life of fruits. The objective of this research was to evaluate the effect of ultraviolet radiation (UV-C) on the control of C. gloeosporioides in 'Niagara Rosada' grapes stored at room condition and under refrigeration. Clusters of 'Niagara Rosada' grapes were inoculated with the pathogen and submitted 2 hours later to different doses of UV-C, 0, 1.05, 2.09, 4.18, and 8.35 kJ m{sup -}2, during the periods of 0, 1, 2, 4, and 8 min, respectively. Then, the clusters were stored under two conditions: 25 +- 1 deg C / 80 +- 5 % RH for 7 days, and at 1 +- 1 deg C / 90 +- 5 % RH for 16 days followed by storage at 25 +- 1 deg C / 80 +- 5 %RH for 5 more days. The grapes were evaluated for rot incidence, stem browning, color of the berries, percentage of detached berries, titratable acidity, total soluble solids, and ratio. It was observed that UV-C radiation was effective in reducing the incidence of C. gloeosporioides on inoculated 'Niagara Rosada' grapes and did not change the physicochemical characteristics of the grapes. (author)

  9. Decreased cell survival and DNA repair capacity after UVC irradiation in association with down-regulation of GRP78/BiP in human RSa cells

    International Nuclear Information System (INIS)

    Zhai Ling; Kita, Kazuko; Wano, Chieko; Wu Yuping; Sugaya, Shigeru; Suzuki, Nobuo

    2005-01-01

    In contrast to extensive studies on the roles of molecular chaperones, such as heat shock proteins, there are only a few reports about the roles of GRP78/BiP, an endoplasmic reticulum (ER) stress-induced molecular chaperone, in mammalian cell responses to DNA-damaging stresses. To investigate whether GRP78/BiP is involved in resistance to a DNA-damaging agent, UVC (principally 254 nm in wavelength), we established human cells with down-regulation of GRP78/BiP by transfection of human RSa cells with antisense cDNA for GRP78/BiP. We found that the transfected cells showed higher sensitivity to UVC-induced cell death than control cells transfected with the vector alone. In the antisense-cDNA transfected cells, the removal capacities of the two major types of UVC-damaged DNA (thymine dimers and (6-4) photoproducts) in vivo and DNA synthesis activity of whole cell extracts to repair UVC-irradiated plasmids in vitro were remarkably decreased compared with those in the control cells. Furthermore, the antisense-cDNA transfected cells also showed slightly higher sensitivity to cisplatin-induced cell death than the control cells. Cisplatin-induced DNA damage is primarily repaired by nucleotide excision repair, like UVC-induced DNA damage. The present results suggest that GRP78/BiP plays a protective role against UVC-induced cell death possibly via nucleotide excision repair, at least in the human RSa cells tested

  10. Efficacy of UV-C irradiation for inactivation of food-borne pathogens on sliced cheese packaged with different types and thicknesses of plastic films.

    Science.gov (United States)

    Ha, Jae-Won; Back, Kyeong-Hwan; Kim, Yoon-Hee; Kang, Dong-Hyun

    2016-08-01

    In this study, the efficacy of using UV-C light to inactivate sliced cheese inoculated with Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes and, packaged with 0.07 mm films of polyethylene terephthalate (PET), polyvinylchloride (PVC), polypropylene (PP), and polyethylene (PE) was investigated. The results show that compared with PET and PVC, PP and PE films showed significantly reduced levels of the three pathogens compared to inoculated but non-treated controls. Therefore, PP and PE films of different thicknesses (0.07 mm, 0.10 mm, and 0.13 mm) were then evaluated for pathogen reduction of inoculated sliced cheese samples. Compared with 0.10 and 0.13 mm, 0.07 mm thick PP and PE films did not show statistically significant reductions compared to non-packaged treated samples. Moreover, there were no statistically significant differences between the efficacy of PP and PE films. These results suggest that adjusted PP or PE film packaging in conjunction with UV-C radiation can be applied to control foodborne pathogens in the dairy industry. Copyright © 2016. Published by Elsevier Ltd.

  11. Evaluating UV-C LED disinfection performance and investigating potential dual-wavelength synergy.

    Science.gov (United States)

    Beck, Sara E; Ryu, Hodon; Boczek, Laura A; Cashdollar, Jennifer L; Jeanis, Kaitlyn M; Rosenblum, James S; Lawal, Oliver R; Linden, Karl G

    2017-02-01

    A dual-wavelength UV-C LED unit, emitting at peaks of 260 nm, 280 nm, and the combination of 260|280 nm together was evaluated for its inactivation efficacy and energy efficiency at disinfecting Escherichia coli, MS2 coliphage, human adenovirus type 2 (HAdV2), and Bacillus pumilus spores, compared to conventional low-pressure and medium-pressure UV mercury vapor lamps. The dual-wavelength unit was also used to measure potential synergistic effects of multiple wavelengths on bacterial and viral inactivation and DNA and RNA damage. All five UV sources demonstrated similar inactivation of E. coli. For MS2, the 260 nm LED was most effective. For HAdV2 and B. pumilus, the MP UV lamp was most effective. When measuring electrical energy per order of reduction, the LP UV lamp was most efficient for inactivating E. coli and MS2; the LP UV and MP UV mercury lamps were equally efficient for HAdV2 and B. pumilus spores. Among the UV-C LEDs, there was no statistical difference in electrical efficiency for inactivating MS2, HAdV2, and B. pumilus spores. The 260 nm and 260|280 nm LEDs had a statistical energy advantage for E. coli inactivation. For UV-C LEDs to match the electrical efficiency per order of log reduction of conventional LP UV sources, they must reach efficiencies of 25-39% or be improved on by smart reactor design. No dual wavelength synergies were detected for bacterial and viral inactivation nor for DNA and RNA damage. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Disinfection of Pseudomonas aeruginosa biofilm contaminated tube lumens with ultraviolet C light emitting diodes

    DEFF Research Database (Denmark)

    Bak, Jimmy; Ladefoged, Søren D; Tvede, Michael

    2010-01-01

    with biofilm was investigated. It was shown that UVC light propagation was possible through both Teflon and catheter tubes (silicone). The disinfection efficiency of the diodes was demonstrated on tubes contaminated artificially with a Pseudomonas aeruginosa biofilm. The tubes were connected to a flow system...... and biofilms were produced during a 3 day period. Tubes in lengths of 10 (Teflon, silicone) and 20 cm (Teflon) were contaminated. Tubes for control and for UVC treatment were contaminated in parallel. Biofilms were sampled from the total inner surface of the tubes. Colony counts on the control samples were...... in the range of 5 x 10(5)-1.3 x 10(9) CFU ml(-1), with disinfection rates in the range 96-100%. The applied UVC doses corresponded to treatment times between 15 and 300 min. Disinfection (100%) was obtained in 10 cm Teflon tubes exposed for 30 min (detection limit...

  13. Disinfection of Pseudomonas aeruginosa biofilm contaminated tube lumens with ultraviolet C light emitting diodes

    DEFF Research Database (Denmark)

    Bak, Jimmy; Ladefoged, S.D.; Tvede, M.

    2010-01-01

    with biofilm was investigated. It was shown that UVC light propagation was possible through both Teflon and catheter tubes ( silicone). The disinfection efficiency of the diodes was demonstrated on tubes contaminated artificially with a Pseudomonas aeruginosa biofilm. The tubes were connected to a flow system...... and biofilms were produced during a 3 day period. Tubes in lengths of 10 ( Teflon, silicone) and 20 cm ( Teflon) were contaminated. Tubes for control and for UVC treatment were contaminated in parallel. Biofilms were sampled from the total inner surface of the tubes. Colony counts on the control samples were...... in the range of 5 x 10(5)-1.3 x 10(9) CFU ml(-1), with disinfection rates in the range 96-100%. The applied UVC doses corresponded to treatment times between 15 and 300 min. Disinfection (100%) was obtained in 10 cm Teflon tubes exposed for 30 min (detection limit...

  14. Study of Leaf Metabolome Modifications Induced by UV-C Radiations in Representative Vitis, Cissus and Cannabis Species by LC-MS Based Metabolomics and Antioxidant Assays

    Directory of Open Access Journals (Sweden)

    Guillaume Marti

    2014-09-01

    Full Text Available UV-C radiation is known to induce metabolic modifications in plants, particularly to secondary metabolite biosynthesis. To assess these modifications from a global and untargeted perspective, the effects of the UV-C radiation of the leaves of three different model plant species, Cissus antarctica Vent. (Vitaceae, Vitis vinifera L. (Vitaceae and Cannabis sativa L. (Cannabaceae, were evaluated by an LC-HRMS-based metabolomic approach. The approach enabled the detection of significant metabolite modifications in the three species studied. For all species, clear modifications of phenylpropanoid metabolism were detected that led to an increased level of stilbene derivatives. Interestingly, resveratrol and piceid levels were strongly induced by the UV-C treatment of C. antarctica leaves. In contrast, both flavonoids and stilbene polymers were upregulated in UV-C-treated Vitis leaves. In Cannabis, important changes in cinnamic acid amides and stilbene-related compounds were also detected. Overall, our results highlighted phytoalexin induction upon UV-C radiation. To evaluate whether UV-C stress radiation could enhance the biosynthesis of bioactive compounds, the antioxidant activity of extracts from control and UV-C-treated leaves was measured. The results showed increased antioxidant activity in UV-C-treated V. vinifera extracts.

  15. Inhibition of Genotoxic Effects of UVC Radiation on Human Keratinocyte HaCaT Cells by Echinacea Purpurea (L.) Moench Herbal Extract

    International Nuclear Information System (INIS)

    Kosalec, I.; Segvic Klaric, M.; Kopjar, N.; Milic, M.

    2013-01-01

    Exposure of skin to ultraviolet (UV) radiation might provoke acute and chronic inflammation and oxidative stress which might cause DNA damage leading to skin photoaging and photocarcinogenesis. Previously we showed that Echinacea purpurea (L.) Moench (EH) extract, rich in phenolic acids, has protective effect on human blood lymphocytes exposed to UVC radiation. In this study we checked whether the pre-treatment of human keratinocyte HaCaT cells with lyophilisate of EH (1 and 10 mg/mL) could reduce or prevent primary DNA damage induced by UVC radiation (253.7 nm) in laboratory conditions. Prior to that experiment we examined cell viability using MTT test upon exposure to EH and UVC (30 and 60 min) alone and in combination. Primary DNA damage in HaCaT cells was studied using the alkaline comet assay. Exposure of cells to EH and UVC alone or EH in combination with UV radiation did not reduce cell viability. Opposite to that UV radiation (30 and 60 min) caused a significant increase in the level of primary DNA damage (P < 0.001). Pre-treatment of cells with both concentrations of EH was not genotoxic to HaCaT cells. Only concentration of 1 mg/mL EH successfully protected the cells against the effects of 30 min exposure to UVC radiation. Positive results obtained in this study speak in favour of continuing the research on effectiveness of Echinacea purpurea preparations and their potential application in developing cosmetic products for skin protection.(author)

  16. Photo-removal of sulfamethoxazole (SMX) by photolytic and photocatalytic processes in a batch reactor under UV-C radiation (λmax = 254 nm)

    International Nuclear Information System (INIS)

    Nasuhoglu, Deniz; Yargeau, Viviane; Berk, Dimitrios

    2011-01-01

    In this study, photolytic and photocatalytic removal of the antibiotic sulfamethoxazole (SMX) under UVC radiation (λ = 254 nm) was investigated. The light intensity distribution inside the batch photoreactor was characterized by azoxybenzene actinometry. The intensity of incident radiation was found to be a strong function of position inside the reactor. 12 mg L -1 of SMX was completely removed within 10 min of irradiation under UVC photolysis, compared to 30 min under TiO 2 photocatalysis. COD measurement was used as an indication of the mineralization efficiency of both processes and higher COD removal with photocatalysis was shown. After 6 h of reaction with photolysis and photocatalysis, 24% and 87% removal of COD was observed, respectively. Two of the intermediate photo-products were identified as sulfanilic acid and 3-amino-5-methylisoxazole by direct comparison of the HPLC chromatograms of standards to those of treated solutions. Ecotoxicity of treated and untreated solutions of SMX towards Daphnia magna was also investigated. It was found that a 3:1 ratio of sample to standard freshwater and a high initial concentration of 60 mg L -1 of SMX were used to obtain reliable and reproducible results. The photo-products formed during photocatalytic and photolytic processes were shown to be generally more toxic than the parent compound.

  17. Light in Condensed Matter in the Upper Atmosphere as the Origin of Homochirality: Circularly Polarized Light from Rydberg Matter

    Science.gov (United States)

    Holmlid, Leif

    2009-08-01

    Clouds of the condensed excited Rydberg matter (RM) exist in the atmospheres of comets and planetary bodies (most easily observed at Mercury and the Moon), where they surround the entire bodies. Vast such clouds are recently proposed to exist in the upper atmosphere of Earth (giving rise to the enormous features called noctilucent clouds, polar mesospheric clouds, and polar mesospheric summer radar echoes). It has been shown in experiments with RM that linearly polarized visible light scattered from an RM layer is transformed to circularly polarized light with a probability of approximately 50%. The circular Rydberg electrons in the magnetic field in the RM may be chiral scatterers. The magnetic and anisotropic RM medium acts as a circular polarizer probably by delaying one of the perpendicular components of the light wave. The delay process involved is called Rabi-flopping and gives delays of the order of femtoseconds. This strong effect thus gives intense circularly polarized visible and UV light within RM clouds. Amino acids and other chiral molecules will experience a strong interaction with this light field in the upper atmospheres of planets. The interaction will vary with the stereogenic conformation of the molecules and in all probability promote the survival of one enantiomer. Here, this strong effect is proposed to be the origin of homochirality. The formation of amino acids in the RM clouds is probably facilitated by the catalytic effect of RM.

  18. Light in condensed matter in the upper atmosphere as the origin of homochirality: circularly polarized light from Rydberg matter.

    Science.gov (United States)

    Holmlid, Leif

    2009-01-01

    Clouds of the condensed excited Rydberg matter (RM) exist in the atmospheres of comets and planetary bodies (most easily observed at Mercury and the Moon), where they surround the entire bodies. Vast such clouds are recently proposed to exist in the upper atmosphere of Earth (giving rise to the enormous features called noctilucent clouds, polar mesospheric clouds, and polar mesospheric summer radar echoes). It has been shown in experiments with RM that linearly polarized visible light scattered from an RM layer is transformed to circularly polarized light with a probability of approximately 50%. The circular Rydberg electrons in the magnetic field in the RM may be chiral scatterers. The magnetic and anisotropic RM medium acts as a circular polarizer probably by delaying one of the perpendicular components of the light wave. The delay process involved is called Rabi-flopping and gives delays of the order of femtoseconds. This strong effect thus gives intense circularly polarized visible and UV light within RM clouds. Amino acids and other chiral molecules will experience a strong interaction with this light field in the upper atmospheres of planets. The interaction will vary with the stereogenic conformation of the molecules and in all probability promote the survival of one enantiomer. Here, this strong effect is proposed to be the origin of homochirality. The formation of amino acids in the RM clouds is probably facilitated by the catalytic effect of RM.

  19. DNA repair after a UV-C irradiation in cultivated human fibroblasts: Studies on patients with actinic keratosis, spinocellular carcinoma and basal cell carcinoma as well as healthy controls. DNA-Reparatur nach UV-C-Bestrahlung in kultivierten menschlichen Fibroplasten: Untersuchungen an Patienten mit aktinischen Keratosen, Spinaliomen und Basaliomen sowie gesunden Kontrollen

    Energy Technology Data Exchange (ETDEWEB)

    Senner, A.

    1984-01-11

    Cultivated fibroblasts from 14 healthy control people and 22 patients were irradiated with UV-C light in increasing doses (0-1-2.5-5 mJ/cm/sup 2/). The incorporation of /sup 3/H-thymidine in the DNA of the fibroblasts which is made visible by the autoradiography technique served as a measure for the unprogrammed DNA synthesis. All of the studied fibroblast types showed with an increase in the UV-C irradiation dose an increase in the repair processes of the DNA. No statistically significant difference could be shown in the repair behaviour of the fibroblasts of controls and patients.

  20. Dependence of leaf surface potential response of a plant (Ficus Elastica) to light irradiation on room temperature; Shokubutsu (gomunoki) hamen den`i no hikari shosha oto no shitsuon izonsei

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, H; Kenmoku, Y; Sakakibara, T [Toyohashi University of Technology, Aichi (Japan); Nakagawa, S [Maizuru National College of Technology, Kyoto (Japan); Kawamoto, T [Shizuoka University, Shizuoka (Japan)

    1997-11-25

    In order to clarify plant body potential information, study was made on a leaf surface potential response to light irradiation. The leaf surface potential change, total transpiration and transpiration rate of Ficus Elastica were measured using light irradiation period and room temperature as parameters. The leaf surface potential change shows a positive peak after the start of light irradiation, while a negative peak after its end. Arrival time to both peaks is constant regardless of the light irradiation period, while decrease with an increase in room temperature. Although the total transpiration increases with room temperature, this tendency disappears with an increase in light irradiation period. The transpiration rate shows its peak after the start of light irradiation. Arrival time to the peak is saturated with the light irradiation period of 60min, while decreases with an increase in room temperature. These results suggest that opening of stomata becomes active with an increase in room temperature, and the peak of the leaf surface potential after the start of light irradiation relates to the opening. 3 refs., 11 figs.

  1. Protective Effects of Chlorella-Derived Peptide Against UVC-Induced Cytotoxicity through Inhibition of Caspase-3 Activity and Reduction of the Expression of Phosphorylated FADD and Cleaved PARP-1 in Skin Fibroblasts

    Directory of Open Access Journals (Sweden)

    Jong Yuh Cherng

    2012-08-01

    Full Text Available UVC irradiation induces oxidative stress and leads to cell death through an apoptotic pathway. This apoptosis is caused by activation of caspase-3 and formation of poly(ADP-ribose polymerase-1 (PARP-1. In this study, the underlying mechanisms of Chlorella derived peptide (CDP activity against UVC-induced cytotoxicity were investigated. Human skin fibroblasts were treated with CDP, vitamin C, or vitamin E after UVC irradiation for a total energy of 15 J/cm2. After the UVC exposure, cell proliferation and caspase-3 activity were measured at 12, 24, 48, and 72 h later. Expression of phosphorylated FADD and cleaved PARP-1 were measured 16 h later. DNA damage (expressed as pyrimidine (6-4 pyrimidone photoproducts DNA concentration and fragmentation assay were performed 24 h after the UVC exposure. Results showed that UVC irradiation induced cytotoxicity in all groups except those treated with CDP. The caspase-3 activity in CDP-treated cells was inhibited from 12 h onward. Expression of phosphorylated FADD and cleaved PARP-1 were also reduced in CDP-treated cells. Moreover, UVC-induced DNA damage and fragmentation were also prevented by the CDP treatment. This study shows that treatment of CDP provides protective effects against UVC-induced cytotoxicity through the inhibition of caspase-3 activity and the reduction of phosphorylated FADD and cleaved PARP-1 expression.

  2. Room-temperature Coulomb staircase in semiconducting InP nanowires modulated with light illumination.

    Science.gov (United States)

    Yamada, Toshishige; Yamada, Hidenori; Lohn, Andrew J; Kobayashi, Nobuhiko P

    2011-02-04

    Detailed electron transport analysis is performed for an ensemble of conical indium phosphide nanowires bridging two hydrogenated n(+)-silicon electrodes. The current-voltage (I-V) characteristics exhibit a Coulomb staircase in the dark with a period of ∼ 1 V at room temperature. The staircase is found to disappear under light illumination. This observation can be explained by assuming the presence of a tiny Coulomb island, and its existence is possible due to the large surface depletion region created within contributing nanowires. Electrons tunnel in and out of the Coulomb island, resulting in the Coulomb staircase I-V. Applying light illumination raises the electron quasi-Fermi level and the tunneling barriers are buried, causing the Coulomb staircase to disappear.

  3. Evaluating efficacy of filtration + UV-C radiation for ballast water treatment at different temperatures

    Science.gov (United States)

    Casas-Monroy, Oscar; Linley, Robert D.; Chan, Po-Shun; Kydd, Jocelyn; Vanden Byllaardt, Julie; Bailey, Sarah

    2018-03-01

    To prevent new ballast water-mediated introductions of aquatic nonindigenous species (NIS), many ships will soon use approved Ballast Water Management Systems (BWMS) to meet discharge standards for the maximum number of viable organisms in ballast water. Type approval testing of BWMS is typically conducted during warmer seasons when plankton concentrations are highest, despite the fact that ships operate globally year-round. Low temperatures encountered in polar and cool temperate climates, particularly during the winter season, may impact treatment efficacy through changes in plankton community composition, biological metabolic rates or chemical reaction rates. Filtration + UV irradiance is one of the most common ballast water treatment methods, but its effectiveness at low temperatures has not been assessed. The objective in this study was to examine the efficacy of filtration + UV-C irradiation treatment at low temperatures for removal or inactivation of phytoplankton and zooplankton populations during simulated ballast water treatment. Organisms from two size classes (≥ 10 to < 50 μm and ≥ 50 μm) were identified and enumerated using microscope and culture techniques. The response of organisms in both size categories to UV-C irradiation was evident across a range of temperatures (18 °C, 12 °C and 2 °C) as a significant decrease in concentration between controls and treated samples. Results indicate that filtration + UV-C irradiation will be effective at low temperatures, with few viable organisms ≥ 10 to < 50 μm recorded even 21 days following UV exposure (significantly lower than in the control treatment).

  4. Quantum Correlations of Light from a Room-Temperature Mechanical Oscillator

    Science.gov (United States)

    Sudhir, V.; Schilling, R.; Fedorov, S. A.; Schütz, H.; Wilson, D. J.; Kippenberg, T. J.

    2017-07-01

    When an optical field is reflected from a compliant mirror, its intensity and phase become quantum-correlated due to radiation pressure. These correlations form a valuable resource: the mirror may be viewed as an effective Kerr medium generating squeezed states of light, or the correlations may be used to erase backaction from an interferometric measurement of the mirror's position. To date, optomechanical quantum correlations have been observed in only a handful of cryogenic experiments, owing to the challenge of distilling them from thermomechanical noise. Accessing them at room temperature, however, would significantly extend their practical impact, with applications ranging from gravitational wave detection to chip-scale accelerometry. Here, we observe broadband quantum correlations developed in an optical field due to its interaction with a room-temperature nanomechanical oscillator, taking advantage of its high-cooperativity near-field coupling to an optical microcavity. The correlations manifest as a reduction in the fluctuations of a rotated quadrature of the field, in a frequency window spanning more than an octave below mechanical resonance. This is due to coherent cancellation of the two sources of quantum noise contaminating the measured quadrature—backaction and imprecision. Supplanting the backaction force with an off-resonant test force, we demonstrate the working principle behind a quantum-enhanced "variational" force measurement.

  5. Physicochemical characterization, antioxidant activity and total phenolic content in 'Gala' apples subjected to different UV-C radiation doses

    Directory of Open Access Journals (Sweden)

    Thaís Gabrielle Dias

    2017-01-01

    Full Text Available UV-C radiation is a food preservation method aimed to extend the life of the product, inactivate microorganisms, and stimulate the synthesis of phenolic compounds. This study aimed to physicochemically characterize and evaluate the antioxidant activity and phenolic content of ‘Gala’ apples subjected to different UV-C radiation doses.The fruits were harvested, sanitized, selected and inserted into a UV-C radiation chamber, and different radiation doses were applied as follows:0 KJ m-2 (0 min., 0.68 KJ m-2 (2 minutes,2.73 KJ m-2 (4 minutes, and 4.10 KJ m-2 (6 minutes. The apples were stored for 120 days at 5 ± 1°C and analyzed after 0, 30, 60, 90, and 120 days of storage. Radiation doses had no influence on parameters, such as weight loss, firmness and Hue angle, and physicochemical aspects, such as pH, soluble solids, titratable acidity and the soluble solids/titratable acidity ratio. The 4.10 KJ m-2 dose was effective and increased the phenolic content and antioxidant activity for up to 90 days while maintaining the content of vitamin C during storage.

  6. A comparative approach of methylparaben photocatalytic degradation assisted by UV-C, UV-A and Vis radiations.

    Science.gov (United States)

    Doná, Giovanna; Dagostin, João Luiz Andreoti; Takashina, Thiago Atsushi; de Castilhos, Fernanda; Igarashi-Mafra, Luciana

    2018-05-01

    Due to the widespread use of methylparaben (MEP) and its high chemical stability, it can be found in wastewater treatment plants and can act as an endocrine disrupting compound. In this study, the photocatalytic degradation and mineralization of MEP solutions were evaluated under UV-A, UV-C and Vis radiations in the presence of the photocatalyst TiO 2 . In this sense, the effects of the catalyst load, pH and MEP initial concentration were studied. Remarkably higher reaction rates and total photodegradation were achieved in systems assisted by UV-C radiation. The complete degradation was achieved after 60 min of reaction using the MEP concentration of 30 mg L -1 at pH 9 and 500 mg L -1 TiO 2 . The experimental data apparently followed a Langmuir-Hinshelwood kinetic model, which could predict 88-98% of the reaction behavior. For the best photodegradation condition, the model predicted an apparent reaction rate constant (k app ) equal to 0.0505 min -1 and an initial reaction rate of 1.5641 mg (L min) -1 . Mineralization analyses showed high removal for MEP and derived compounds from the initial solution when using UV-C after 90 min of reaction. The lower toxicity was also confirmed by in vivo tests using MEP solutions previously treated by photocatalysis.

  7. COMPARATIVE ANALYSIS USING DIPIRONA DEGRADATION PROCESS WITH PHOTO-FENTON UV-C LIGHT AND SOLAR RADIATION

    Directory of Open Access Journals (Sweden)

    Daniella Carla Napoleão

    2015-01-01

    Full Text Available The contamination of water bodies is a major concern on the part of scientists from different parts of the world. Domestic and industrial activities are the cause of the daily pouring of various types of pollutants which are in most cases resistant to conventional treatments of waters. Among the contaminants, especially noteworthy are the drugs in which it is found that 50% to 90% are discarded without treatment. The concerns about these substances are the adverse effects to human health and animals, especially in aquatic environments. The advanced oxidation processes (AOP have been studied and applied as an efficient alternative treatment, in order that it can be applied to the degradation of the different pollutants, considering that can generate hydroxyl radicals, highly reactive even somewhat selective. This study evaluated the efficiency of the photo-Fenton process using UV-C radiation and sunlight to degradation of the drug dipyrone in aqueous solution contaminated with the active ingredient of the drug at a concentration of 20 mg.L-1. Assays were performed with 50 mL aliquots of the solution following 23 factorial designs with central point, and the variables studied: addition of H2O2, adding FeSO4.7H2O and time. The detection and quantification of dipyrone before and after the AOP was performed by high performance liquid chromatography (HPLC and verified that about DE100% degradation of the compound was obtained.

  8. UV-light-assisted ethanol sensing characteristics of g-C3N4/ZnO composites at room temperature

    Science.gov (United States)

    Zhai, Jiali; Wang, Tao; Wang, Chuang; Liu, Dechen

    2018-05-01

    A highly efficient UV-light-assisted room temperature sensor based on g-C3N4/ZnO composites were prepared by an in situ precipitation method. The thermostability, composition, structure, and morphology properties of the as-prepared g-C3N4/ZnO composites were characterized by TGA, XRD, FT-IR, TEM, and XPS, respectively. And then, we studied the ethanol (C2H5OH) sensing performance of the g-C3N4/ZnO composites at the room temperature. Compared with pure ZnO and g-C3N4, the gas sensing activity of g-C3N4/ZnO composites was greatly improved at room temperature, for example, the g-C3N4/ZnO-8% composites showed an obvious response of 121-40 ppm C2H5OH at room temperature, which was 60 times higher than the pure ZnO based on the sensors under the same condition. The great enhancement of the C2H5OH sensing properties of composites can be understood by the efficient separation of photogenerated charge carriers of g-C3N4/ZnO heterogeneous and the UV-light catalytic effect. Finally, a possible mechanism for the gas sensing activity was proposed.

  9. Effectiveness of two-sided UV-C treatments in inhibiting natural microflora and extending the shelf-life of minimally processed 'Red Oak Leaf' lettuce.

    Science.gov (United States)

    Allende, Ana; McEvoy, James L; Luo, Yaguang; Artes, Francisco; Wang, Chien Y

    2006-05-01

    The use of UV-C radiation treatments to inhibit the microbial growth and extend the shelf-life of minimally processed 'Red Oak Leaf' lettuce was investigated. Initially, UV-C resistance of 20 bacterial strains from different genera often associated with fresh produce (Enterobacter, Erwinia, Escherichia, Leuconostoc, Pantoea, Pseudomonas, Rahnela, Salmonella, Serratia and Yersinia) were tested in vitro. Most of the bacterial strains were inhibited with the minimum dose (30 J m(-2)). Erwinia carotovora, Leuconostoc carnosum, Salmonella typhimurium, and Yersinia aldovae were the most resistant strains requiring a UV-C dose of 85 J m(-2) to completely inhibit growth. An in vivo study consisted of treating minimally processed 'Red Oak Leaf' lettuce (Lactuca sativa) with UV-C at three radiation doses (1.18, 2.37 and 7.11 kJ m(-2)) on each side of the leaves and storing the product under passive MAP conditions at 5 degrees C for up to 10 days. The gas composition inside packages varied significantly among the treatments, with CO2 concentrations positively and O2 concentrations negatively correlating with the radiation dose. All the radiation doses were effective in reducing the natural microflora of the product, although the highest doses showed the greatest microbial inhibitions. Taking into account the microbial limit set by Spanish legislation [Boletín Oficial del Estado (BOE), 2001. Normas de higiene para la elaboración, distribución y comercio de comidas preparadas, Madrid, Spain, Real Decreto 3484/2000, pp. 1435-1441], all UV-C treatments extended the shelf-life of the product. However, the 7.11 kJ m(-2) dose induced tissue softening and browning after 7 days of storage at 5 degrees C. Therefore, the use of two sided UV-C radiation, at the proper dose, is effective in reducing the natural microflora and extending the shelf-life of minimally processed 'Red Oak Leaf' lettuce.

  10. First Results of Using a UVTron Flame Sensor to Detect Alpha-Induced Air Fluorescence in the UVC Wavelength Range

    Directory of Open Access Journals (Sweden)

    Anita J. Crompton

    2017-11-01

    Full Text Available In this work, a robust stand-off alpha detection method using the secondary effects of alpha radiation has been sought. Alpha particles ionise the surrounding atmosphere as they travel. Fluorescence photons produced as a consequence of this can be used to detect the source of the alpha emissions. This paper details experiments carried out to detect this fluorescence, with the focus on photons in the ultraviolet C (UVC wavelength range (180–280 nm. A detector, UVTron R9533 (Hamamatsu, 325-6, Sunayama-cho, Naka-ku, Hamamatsu City, Shizuoka Pref., 430-8587, Japan, designed to detect the UVC emissions from flames for fire alarm purposes, was tested in various gas atmospheres with a 210Po alpha source to determine if this could provide an avenue for stand-off alpha detection. The results of the experiments show that this detector is capable of detecting alpha-induced air fluorescence in normal indoor lighting conditions, as the interference from daylight and artificial lighting is less influential on this detection system which operates below the UVA and UVB wavelength ranges (280–315 nm and 315–380 nm respectively. Assuming a standard 1 r 2 drop off in signal, the limit of detection in this configuration can be calculated to be approximately 240 mm, well beyond the range of alpha-particles in air, which indicates that this approach could have potential for stand-off alpha detection. The gas atmospheres tested produced an increase in the detector count, with xenon having the greatest effect with a measured 52% increase in the detector response in comparison to the detector response in an air atmosphere. This type of alpha detection system could be operated at a distance, where it would potentially provide a more cost effective, safer, and faster solution in comparison with traditional alpha detection methods to detect and characterise alpha contamination in nuclear decommissioning and security applications.

  11. Potential of UVC germicidal irradiation in suppressing crown rot disease, retaining postharvest quality and antioxidant capacity of Musa AAA "Berangan" during fruit ripening.

    Science.gov (United States)

    S Mohamed, Nuratika Tamimi; Ding, Phebe; Kadir, Jugah; M Ghazali, Hasanah

    2017-09-01

    Crown rot caused by fungal pathogen is the most prevalent postharvest disease in banana fruit that results significant economic losses during transportation, storage, and ripening period. Antifungal effects of ultraviolet C (UVC) irradiation at doses varied from 0.01 to 0.30 kJ m -2 were investigated in controlling postharvest crown rot disease, maintenance of fruit quality, and the effects on antioxidant capacity of Berangan banana fruit during ripening days at 25 ± 2°C and 85% RH. Fruits irradiated with 0.30 kJ m -2 exhibited the highest (i.e., 62.51%) reduction in disease severity. However, the application of UVC at all doses caused significant browning damages on fruit peel except the dose of 0.01 kJ m -2 . This dose synergistically reduced 46.25% development of postharvest crown and did not give adverse effects on respiration rate, ethylene production, weight loss, firmness, color changes, soluble solids concentration, titratable acidity, and pH in banana as compared to the other treatments and control. Meanwhile, the dose also enhanced a significant higher level of total phenolic content, FRAP, and DPPH values than in control fruits indicating the beneficial impact of UVC in fruit nutritional quality. The results of scanning electron micrographs confirmed that UVC irradiation retarded the losses of wall compartments, thereby maintained the cell wall integrity in the crown tissue of banana fruit. The results suggest that using 0.01 kJ m -2 UVC irradiation dose as postharvest physical treatment, the crown rot disease has potential to be controlled effectively together with maintaining quality and antioxidant of banana fruit.

  12. Photo-removal of sulfamethoxazole (SMX) by photolytic and photocatalytic processes in a batch reactor under UV-C radiation ({lambda}{sub max} = 254 nm)

    Energy Technology Data Exchange (ETDEWEB)

    Nasuhoglu, Deniz; Yargeau, Viviane [Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, Quebec, H3A 2B2 (Canada); Berk, Dimitrios, E-mail: dimitrios.berk@mcgill.ca [Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, Quebec, H3A 2B2 (Canada)

    2011-02-15

    In this study, photolytic and photocatalytic removal of the antibiotic sulfamethoxazole (SMX) under UVC radiation ({lambda} = 254 nm) was investigated. The light intensity distribution inside the batch photoreactor was characterized by azoxybenzene actinometry. The intensity of incident radiation was found to be a strong function of position inside the reactor. 12 mg L{sup -1} of SMX was completely removed within 10 min of irradiation under UVC photolysis, compared to 30 min under TiO{sub 2} photocatalysis. COD measurement was used as an indication of the mineralization efficiency of both processes and higher COD removal with photocatalysis was shown. After 6 h of reaction with photolysis and photocatalysis, 24% and 87% removal of COD was observed, respectively. Two of the intermediate photo-products were identified as sulfanilic acid and 3-amino-5-methylisoxazole by direct comparison of the HPLC chromatograms of standards to those of treated solutions. Ecotoxicity of treated and untreated solutions of SMX towards Daphnia magna was also investigated. It was found that a 3:1 ratio of sample to standard freshwater and a high initial concentration of 60 mg L{sup -1} of SMX were used to obtain reliable and reproducible results. The photo-products formed during photocatalytic and photolytic processes were shown to be generally more toxic than the parent compound.

  13. Spectral dependence of some UV-B and UV-C responses of Tetrahymena pyriformis irradiated with dye laser generated UV

    International Nuclear Information System (INIS)

    Calkins, John; Colley, Ed; Wheeler, John; Kentucky Univ., Lexington

    1987-01-01

    We have generated UV-B and UV-C radiations using a flashlamp driven tunable dye laser combined with frequency doubling crystals. Using this novel UV source, we have investigated lethality and its modification by growth phase, photoreactivation and caffeine in Tetrahymena pyriformis at 254 nm and from 260-315 nm in 5 nm steps. From the observed responses we have constructed action spectra for lethality, with or without caffeine (a repair inhibitor) and under conditions of photoreactivation. We have also estimated quantum efficiencies for these responses. Our observations suggest that complex changes in response occur at several wavelengths over the UV-C and UV-B regions. (author)

  14. Can biowarfare agents be defeated with light?

    Science.gov (United States)

    Vatansever, Fatma; Ferraresi, Cleber; de Sousa, Marcelo Victor Pires; Yin, Rui; Rineh, Ardeshir; Sharma, Sulbha K; Hamblin, Michael R

    2013-01-01

    Biological warfare and bioterrorism is an unpleasant fact of 21st century life. Highly infectious and profoundly virulent diseases may be caused in combat personnel or in civilian populations by the appropriate dissemination of viruses, bacteria, spores, fungi, or toxins. Dissemination may be airborne, waterborne, or by contamination of food or surfaces. Countermeasures may be directed toward destroying or neutralizing the agents outside the body before infection has taken place, by destroying the agents once they have entered the body before the disease has fully developed, or by immunizing susceptible populations against the effects. A range of light-based technologies may have a role to play in biodefense countermeasures. Germicidal UV (UVC) is exceptionally active in destroying a wide range of viruses and microbial cells, and recent data suggests that UVC has high selectivity over host mammalian cells and tissues. Two UVA mediated approaches may also have roles to play; one where UVA is combined with titanium dioxide nanoparticles in a process called photocatalysis, and a second where UVA is combined with psoralens (PUVA) to produce “killed but metabolically active” microbial cells that may be particularly suitable for vaccines. Many microbial cells are surprisingly sensitive to blue light alone, and blue light can effectively destroy bacteria, fungi, and Bacillus spores and can treat wound infections. The combination of photosensitizing dyes such as porphyrins or phenothiaziniums and red light is called photodynamic therapy (PDT) or photoinactivation, and this approach cannot only kill bacteria, spores, and fungi, but also inactivate viruses and toxins. Many reports have highlighted the ability of PDT to treat infections and stimulate the host immune system. Finally pulsed (femtosecond) high power lasers have been used to inactivate pathogens with some degree of selectivity. We have pointed to some of the ways light-based technology may be used to defeat

  15. Reduction of Zika virus infectivity in platelet concentrates after treatment with ultraviolet C light and in plasma after treatment with methylene blue and visible light.

    Science.gov (United States)

    Fryk, Jesse J; Marks, Denese C; Hobson-Peters, Jody; Watterson, Daniel; Hall, Roy A; Young, Paul R; Reichenberg, Stefan; Tolksdorf, Frank; Sumian, Chryslain; Gravemann, Ute; Seltsam, Axel; Faddy, Helen M

    2017-11-01

    Zika virus (ZIKV) has emerged as a potential threat to transfusion safety worldwide. Pathogen inactivation is one approach to manage this risk. In this study, the efficacy of the THERAFLEX UV-Platelets system and THERAFLEX MB-Plasma system to inactivate ZIKV in platelet concentrates (PCs) and plasma was investigated. PCs spiked with ZIKV were treated with the THERAFLEX UV-Platelets system at 0.05, 0.10, 0.15, and 0.20 J/cm 2 UVC. Plasma spiked with ZIKV was treated with the THERAFLEX MB-Plasma system at 20, 40, 60, and 120 J/cm 2 light at 630 nm with at least 0.8 µmol/L methylene blue (MB). Samples were taken before the first and after each illumination dose and tested for residual virus. For each system the level of viral reduction was determined. Treatment of PCs with THERAFLEX UV-Platelets system resulted in a mean of 5 log reduction in ZIKV infectivity at the standard UVC dose (0.20 J/cm 2 ), with dose dependency observed with increasing UVC dose. For plasma treated with MB and visible light, ZIKV infectivity was reduced by a mean of at least 5.68 log, with residual viral infectivity reaching the detection limit of the assay at 40 J/cm 2 (one-third the standard dose). Our study demonstrates that the THERAFLEX UV-Platelets system and THERAFLEX MB-Plasma system can reduce ZIKV infectivity in PCs and pooled plasma to the detection limit of the assays used. These findings suggest both systems have the capacity to be an effective option to manage potential ZIKV transfusion transmission risk. © 2017 AABB.

  16. 207-nm UV Light-A Promising Tool for Safe Low-Cost Reduction of Surgical Site Infections. II: In-Vivo Safety Studies.

    Science.gov (United States)

    Buonanno, Manuela; Stanislauskas, Milda; Ponnaiya, Brian; Bigelow, Alan W; Randers-Pehrson, Gerhard; Xu, Yanping; Shuryak, Igor; Smilenov, Lubomir; Owens, David M; Brenner, David J

    2016-01-01

    UVC light generated by conventional germicidal lamps is a well-established anti-microbial modality, effective against both bacteria and viruses. However, it is a human health hazard, being both carcinogenic and cataractogenic. Earlier studies showed that single-wavelength far-UVC light (207 nm) generated by excimer lamps kills bacteria without apparent harm to human skin tissue in vitro. The biophysical explanation is that, due to its extremely short range in biological material, 207 nm UV light cannot penetrate the human stratum corneum (the outer dead-cell skin layer, thickness 5-20 μm) nor even the cytoplasm of individual human cells. By contrast, 207 nm UV light can penetrate bacteria and viruses because these cells are physically much smaller. To test the biophysically-based hypothesis that 207 nm UV light is not cytotoxic to exposed mammalian skin in vivo. Hairless mice were exposed to a bactericidal UV fluence of 157 mJ/cm2 delivered by a filtered Kr-Br excimer lamp producing monoenergetic 207-nm UV light, or delivered by a conventional 254-nm UV germicidal lamp. Sham irradiations constituted the negative control. Eight relevant cellular and molecular damage endpoints including epidermal hyperplasia, pre-mutagenic UV-associated DNA lesions, skin inflammation, and normal cell proliferation and differentiation were evaluated in mice dorsal skin harvested 48 h after UV exposure. While conventional germicidal UV (254 nm) exposure produced significant effects for all the studied skin damage endpoints, the same fluence of 207 nm UV light produced results that were not statistically distinguishable from the zero exposure controls. As predicted by biophysical considerations and in agreement with earlier in vitro studies, 207-nm light does not appear to be significantly cytotoxic to mouse skin. These results suggest that excimer-based far-UVC light could potentially be used for its anti-microbial properties, but without the associated hazards to skin of conventional

  17. Safety measures in exposure room

    International Nuclear Information System (INIS)

    Muhammad Jamal Md Isa

    2004-01-01

    The contents of this chapter are follows - The exposure room: location and dimension, material and thickness, windows, doors and other openings; Position of the Irradiating Apparatus, Use of Space Adjoining the Room, Warning Signs/Light, Dark Room. Materials and Apparatus: Classification of Areas, Local Rules, Other General Safety Requirements

  18. Breakthrough of ultraviolet light from various brands of fluorescent lamps: Lethal effects on DNA repair-defective bacteria

    International Nuclear Information System (INIS)

    Hartman, P.E.; Biggley, W.H.

    1996-01-01

    In a comparative study of 17 pairs of 15 W fluorescent lamps intended for use in homes and purchased in local stores, we detect over 10-fold differences in UVB + UVC emissions between various lamps. This breakthrough of ultraviolet (UV) light is in part correlated with ability of lamps to kill DNA repair-defective recA - uvrB - Salmonella. Relative proficiency of lamps in eliciting photoreactivation of UV-induced DNA lesions also plays a prominent role in the relative rates of bacterial inactivation by emissions from different lamps. Lamps made in Chile, such as Phillips brand lamps and one type of General Electric lamp, produce far less UVB + UVC and fail to kill recA - uvrB - bacteria. In contrast, all tested lamps manufactured in the USA, Hungary, and Japan exhibit readily observed deleterious biological effects. When an E. coli recA - uvrB - phr - (photolyase-negative) triple mutant is used for assay, lethal radiations are detected from all lamps, and single-hit exponential inactivation rates rather closely correlate to amount of directly measured UVB + UVC output of each pair of lamps. Although all lamps tested may meet international and Unite States standards for radiation safely, optimal practices in lamp manufacture are clearly capable of decreasing human exposure to indoor UV light. 38 refs., 3 figs., 1 tab

  19. Lighting Options for Homes.

    Energy Technology Data Exchange (ETDEWEB)

    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)

  20. Evaluation of a dark-room

    International Nuclear Information System (INIS)

    Passos, J.C.

    1987-01-01

    The adequate operation conditions of a dark-room are essential to guarantee the image quality, the least exposure of the patient and the staff, contributing also to reduce the expenses with specific equipments and processing solutions. Therefore, to install a dark-room, it is necessary a previous study about its physical dimensions, the location of equipments, accessories, light safeguards and visual warning, besides adequate darkening and correct filme processing. We propose three basic tests to check the adequacy and the integrity of a dark-room: light safeguards test, hygiene test, developing time and temperature test. (Author) [pt

  1. Subnuclear localization, rates and effectiveness of UVC-induced unscheduled DNA synthesis visualized by fluorescence widefield, confocal and super-resolution microscopy.

    Science.gov (United States)

    Pierzyńska-Mach, Agnieszka; Szczurek, Aleksander; Cella Zanacchi, Francesca; Pennacchietti, Francesca; Drukała, Justyna; Diaspro, Alberto; Cremer, Christoph; Darzynkiewicz, Zbigniew; Dobrucki, Jurek W

    2016-01-01

    Unscheduled DNA synthesis (UDS) is the final stage of the process of repair of DNA lesions induced by UVC. We detected UDS using a DNA precursor, 5-ethynyl-2'-deoxyuridine (EdU). Using wide-field, confocal and super-resolution fluorescence microscopy and normal human fibroblasts, derived from healthy subjects, we demonstrate that the sub-nuclear pattern of UDS detected via incorporation of EdU is different from that when BrdU is used as DNA precursor. EdU incorporation occurs evenly throughout chromatin, as opposed to just a few small and large repair foci detected by BrdU. We attribute this difference to the fact that BrdU antibody is of much larger size than EdU, and its accessibility to the incorporated precursor requires the presence of denatured sections of DNA. It appears that under the standard conditions of immunocytochemical detection of BrdU only fragments of DNA of various length are being denatured. We argue that, compared with BrdU, the UDS pattern visualized by EdU constitutes a more faithful representation of sub-nuclear distribution of the final stage of nucleotide excision repair induced by UVC. Using the optimized integrated EdU detection procedure we also measured the relative amount of the DNA precursor incorporated by cells during UDS following exposure to various doses of UVC. Also described is the high degree of heterogeneity in terms of the UVC-induced EdU incorporation per cell, presumably reflecting various DNA repair efficiencies or differences in the level of endogenous dT competing with EdU within a population of normal human fibroblasts.

  2. Effects of Vinification Techniques Combined with UV-C Irradiation on Phenolic Contents of Red Wines.

    Science.gov (United States)

    Tahmaz, Hande; Söylemezoğlu, Gökhan

    2017-06-01

    Red wines are typically high in phenolic and antioxidant capacity and both of which can be increased by vinification techniques. This study employed 3 vinification techniques to assess the increase in phenolic compounds and antioxidant capacity. Wines were obtained from Boğazkere grape cultivar by techniques of classical maceration, cold maceration combined with ultraviolet light (UV) irradiation, and thermovinification combined with UV irradiation and changes in phenolic contents were examined. Total phenolic and anthocyanin contents and trolox equivalent antioxidant capacity of wines were measured spectrophotometrically and phenolic contents (+)-catechin, (-)-epicatechin, rutin, quercetin, trans-resveratrol, and cis-resveratrol were measured by High Pressure Liquid Chromatography with Diode Array Detection (HPLC-DAD). As a result of the study, the highest phenolic content except for quercetin was measured in the wines obtained by thermovinification combined with UV irradiation. We demonstrated that the highest phenolic compounds with health effect, total phenolic compounds, total anthocyanin, and antioxidant activity were obtained from thermovinification with UV-C treatment than classical wine making. © 2017 Institute of Food Technologists®.

  3. Inactivation of avirulent Yersinia pestis on food and food contact surfaces by ultraviolet light and freezing

    Science.gov (United States)

    Yersinia pestis, the causative agent of plague, can occasionally be contracted as a naso-pharangeal or gastrointestinal illness through consumption of contaminated meat. In this study, the use of 254 nm ultraviolet light (UV-C) to inactivate a multi-isolate cocktail of avirulent Y. pestis on food an...

  4. Ultraviolet light and ozone stimulate accumulation of salicylic acid, pathogenesis-related proteins and virus resistance in tobacco

    International Nuclear Information System (INIS)

    Yalpani, N.; Enyedi, A.J.; León, J.; Raskin, I.

    1994-01-01

    In tobacco (Nicotiana tabacum L. cv. Xanthinc), salicylic acid (SA) levels increase in leaves inoculated by necrotizing pathogens and in healthy leaves located above the inoculated site. Systemic SA increase may trigger disease resistance and synthesis of pathogenesis-related proteins (PR proteins). Here we report that ultraviolet (UV)-C light or ozone induced biochemical responses similar to those induced by necrotizing pathogens. Exposure of leaves to UV-C light or ozone resulted in a transient ninefold increase in SA compared to controls. In addition, in UV-light-irradiated plants, SA increased nearly fourfold to 0.77 μg·g −1 fresh weight in leaves that were shielded from UV light. Increased SA levels were accompanied by accumulation of an SA conjugate and by an increase in the activity of benzoic acid 2-hydroxylase which catalyzes SA biosynthesis. In irradiated and in unirradiated leaves of plants treated with UV light, as well as in plants fumigated with ozone, PR proteins 1a and 1b accumulated. This was paralleled by the appearance of induced resistance to a subsequent challenge with tobacco mosaic virus. The results suggest that UV light, ozone fumigation and tobacco mosaic virus can activate a common signal-transduction pathway that leads to SA and PR-protein accumulation and increased disease resistance. (author)

  5. Light-trapping for room temperature Bose-Einstein condensation in InGaAs quantum wells.

    Science.gov (United States)

    Vasudev, Pranai; Jiang, Jian-Hua; John, Sajeev

    2016-06-27

    We demonstrate the possibility of room-temperature, thermal equilibrium Bose-Einstein condensation (BEC) of exciton-polaritons in a multiple quantum well (QW) system composed of InGaAs quantum wells surrounded by InP barriers, allowing for the emission of light near telecommunication wavelengths. The QWs are embedded in a cavity consisting of double slanted pore (SP2) photonic crystals composed of InP. We consider exciton-polaritons that result from the strong coupling between the multiple quantum well excitons and photons in the lowest planar guided mode within the photonic band gap (PBG) of the photonic crystal cavity. The collective coupling of three QWs results in a vacuum Rabi splitting of 3% of the bare exciton recombination energy. Due to the full three-dimensional PBG exhibited by the SP2 photonic crystal (16% gap to mid-gap frequency ratio), the radiative decay of polaritons is eliminated in all directions. Due to the short exciton-phonon scattering time in InGaAs quantum wells of 0.5 ps and the exciton non-radiative decay time of 200 ps at room temperature, polaritons can achieve thermal equilibrium with the host lattice to form an equilibrium BEC. Using a SP2 photonic crystal with a lattice constant of a = 516 nm, a unit cell height of 2a=730nm and a pore radius of 0.305a = 157 nm, light in the lowest planar guided mode is strongly localized in the central slab layer. The central slab layer consists of 3 nm InGaAs quantum wells with 7 nm InP barriers, in which excitons have a recombination energy of 0.944 eV, a binding energy of 7 meV and a Bohr radius of aB = 10 nm. We take the exciton recombination energy to be detuned 35 meV above the lowest guided photonic mode so that an exciton-polariton has a photonic fraction of approximately 97% per QW. This increases the energy range of small-effective-mass photonlike states and increases the critical temperature for the onset of a Bose-Einstein condensate. With three quantum wells in the central slab layer

  6. Experimental and numerical study of light gas dispersion in a ventilated room

    Energy Technology Data Exchange (ETDEWEB)

    Gelain, Thomas, E-mail: thomas.gelain@irsn.fr; Prévost, Corinne

    2015-11-15

    Highlights: • Presentation of many experimental local data for different configurations. • Highlight of the influence of numerical parameters used in the CFD code. • Validation of the CFD code ANSYS CFX on the basis of experimental data. - Abstract: The objective of this study is to validate the ANSYS CFX version 12 computational code on the basis of light gas dispersion tests performed in two ventilated rooms. It follows an initial study on heavy gas dispersion carried out by Ricciardi et al. (2008). First, a study of sensitivity to various numerical parameters allows a set of reference data to be developed and the influence of the numerical scheme of advection to be revealed. Second, two helium (simulating hydrogen) dispersion test grids are simulated for the two rooms studied, and the results of the calculations are compared with experimental results. The very good agreement between these results allows the code and its dataset to be validated for this application. In future, a study with higher levels of helium (on the order of 4% vol at equilibrium) is envisaged in the context of safety analyses related to the hydrogen risk, these levels representing the lower explosive limit (LEL) of hydrogen.

  7. Microflow photochemistry: UVC-induced [2 + 2]-photoadditions to furanone in a microcapillary reactor

    Directory of Open Access Journals (Sweden)

    Sylvestre Bachollet

    2013-10-01

    Full Text Available [2 + 2]-Cycloadditions of cyclopentene and 2,3-dimethylbut-2-ene to furanone were investigated under continuous-flow conditions. Irradiations were conducted in a FEP-microcapillary module which was placed in a Rayonet chamber photoreactor equipped with low wattage UVC-lamps. Conversion rates and isolated yields were compared to analogue batch reactions in a quartz test tube. In all cases examined, the microcapillary reactor furnished faster conversions and improved product qualities.

  8. Resistance of the genome of Escherichia coli and Listeria monocytogenes to irradiation evaluated by the induction of cyclobutane pyrimidine dimers and 6-4 photoproducts using gamma and UV-C radiations

    Science.gov (United States)

    Beauchamp, S.; Lacroix, M.

    2012-08-01

    The effect of gamma and UV-C irradiation on the production of cyclobutane pyrimidine dimers (CPDs) and 6-4 photoproducts (6-4 PPs) in DNA was investigated to compare the natural resistance of the genome of a Gram-positive bacterium and a Gram-negative bacterium against irradiation. Solution of pure DNA and bacterial strains Listeria monocytogenes and Escherichia coli were irradiated using gamma and UV-C rays. Extracted DNA from bacteria and pure DNA samples were then analysed by ELISA using anti-CPDs and anti-6-4 PPs monoclonal antibodies. The results show that gamma rays, as well as UV-C rays, induce the formation of CPDs and 6-4 PPs in DNA. During UV-C irradiation, the three samples showed a difference in their sensitivity against formation of CPDs (P≤0.05). Pure DNA was the most sensitive while the genome of L. monocytogenes was the most resistant. Also during UV-C irradiation, the genome of L. monocytogenes was the only one to show a significant resistance against formation of 6-4 PPs (P≤0.05). During gamma irradiation, for both types of lesion, pure DNA and the genome of E. coli did not show significant difference in their sensitivity (P>0.05) while the genome of L. monocytogenes showed a resistance against formation of CPDs and 6-4 PPs.

  9. Nonvariceal upper gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Burke, Stephen J.; Weldon, Derik; Sun, Shiliang; Golzarian, Jafar

    2007-01-01

    Nonvariceal upper gastrointestinal bleeding (NUGB) remains a major medical problem even after advances in medical therapy with gastric acid suppression and cyclooxygenase (COX-2) inhibitors. Although the incidence of upper gastrointestinal bleeding presenting to the emergency room has slightly decreased, similar decreases in overall mortality and rebleeding rate have not been experienced over the last few decades. Many causes of upper gastrointestinal bleeding have been identified and will be reviewed. Endoscopic, radiographic and angiographic modalities continue to form the basis of the diagnosis of upper gastrointestinal bleeding with new research in the field of CT angiography to diagnose gastrointestinal bleeding. Endoscopic and angiographic treatment modalities will be highlighted, emphasizing a multi-modality treatment plan for upper gastrointestinal bleeding. (orig.)

  10. Nonvariceal upper gastrointestinal bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Burke, Stephen J.; Weldon, Derik; Sun, Shiliang [University of Iowa, Department of Radiology, Iowa, IA (United States); Golzarian, Jafar [University of Iowa, Department of Radiology, Iowa, IA (United States); University of Iowa, Department of Radiology, Carver College of Medicine, Iowa, IA (United States)

    2007-07-15

    Nonvariceal upper gastrointestinal bleeding (NUGB) remains a major medical problem even after advances in medical therapy with gastric acid suppression and cyclooxygenase (COX-2) inhibitors. Although the incidence of upper gastrointestinal bleeding presenting to the emergency room has slightly decreased, similar decreases in overall mortality and rebleeding rate have not been experienced over the last few decades. Many causes of upper gastrointestinal bleeding have been identified and will be reviewed. Endoscopic, radiographic and angiographic modalities continue to form the basis of the diagnosis of upper gastrointestinal bleeding with new research in the field of CT angiography to diagnose gastrointestinal bleeding. Endoscopic and angiographic treatment modalities will be highlighted, emphasizing a multi-modality treatment plan for upper gastrointestinal bleeding. (orig.)

  11. Facile synthesis of flower-like BiOI hierarchical spheres at room temperature with high visible-light photocatalytic activity

    International Nuclear Information System (INIS)

    Wang, Xiao-jing; Li, Fa-tang; Li, Dong-yan; Liu, Rui-hong; Liu, Shuang-jun

    2015-01-01

    Graphical abstract: - Highlights: • Flower-like BiOI hierarchical sphere is obtained in the presence of ethylene glycol. • A template free hydrolysis route is employed at room temperature. • Ethylene glycol plays an important role in assembling BiOI nanoflakes to form spheres. • The BiOI sphere shows high visible-light photocatalytic activity and good stability. - Abstract: Flower-like BiOI hierarchical spheres are prepared at room temperature via a template free route simply by dropping water into ethylene glycol (EG) solution containing reactants based on the hydrolysis and oriented assembly roles of water and EG, respectively. The BiOI samples are characterized by X-ray diffraction (XRD), nitrogen adsorption/desorption, emission scanning electron microscopy (SEM), UV–Vis diffuse reflectance spectra (UV–Vis DRS), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The photocatalytic reaction rate constant of the as-prepared BiOI hierarchical spheres is 15.8, 13.3, and 2.0 times that of BiOI nanoflakes obtained in the absence of EG in degradation of anionic dye (methyl orange), cationic dye (methylene blue), and colorless target pollutant (phenol), respectively, under the visible-light irradiation, which can be attributed to its unique flower-like structure for utilization of light, small crystal size, and large specific surface area

  12. Effect of postharvest UV-C treatment on the bacterial diversity of Ataulfo mangoes by PCR-DGGE, survival of E. coli and antimicrobial activity

    Science.gov (United States)

    Fernández-Suárez, Rocío; Ramírez-Villatoro, Guadalupe; Díaz-Ruiz, Gloria; Eslava, Carlos; Calderón, Montserrat; Navarro-Ocaña, Arturo; Trejo-Márquez, Andrea; Wacher, Carmen

    2013-01-01

    Since Mexico is the second largest exporter of mangoes, its safety assurance is essential. Research in microbial ecology and knowledge of complex interactions among microbes must be better understood to achieve maximal control of pathogens. Therefore, we investigated the effect of UV-C treatments on bacterial diversity of the Ataulfo mangoes surface using PCR-DGGE analysis of variable region V3 of 16S rRNA genes, and the survival of E. coli, by plate counting. The UV-C irradiation reduced the microbial load on the surface of mangoes immediately after treatment and the structure of bacterial communities was modified during storage. We identified the key members of the bacterial communities on the surface of fruits, predominating Enterobacter genus. Genera as Lactococcus and Pantoea were only detected on the surface of non-treated (control) mangoes. This could indicate that these genera were affected by the UV-C treatment. On the other hand, the treatment did not have a significant effect on survival of E. coli. However, genera that have been recognized as antagonists against foodborne pathogens were identified in the bands patterns. Also, phenolic compounds were determined by HPLC and antimicrobial activity was assayed according to the agar diffusion method. The main phenolic compounds were chlorogenic, gallic, and caffeic acids. Mango peel methanol extracts (UV-C treated and control mangoes) showed antimicrobial activity against strains previously isolated from mango, detecting significant differences (P < 0.05) among treated and control mangoes after 4 and 12 days of storage. Ps. fluorescens and Ps. stutszeri were the most sensitive. PMID:23761788

  13. Comparison of the role of attachment, aggregation and internalisation of microorganisms in UVC and UVA (solar) disinfection.

    Science.gov (United States)

    Bichai, Françoise; Léveillé, Simon; Barbeau, Benoit

    2011-01-01

    In this comparative study, the impact of two microbial protective mechanisms against simulated UVA disinfection was assessed by using protocols previously developed for UVC disinfection assays. (i) The impact of natural microorganism aggregation and attachment to particles was assessed by targeting total coliform bacteria in natural surface water samples. (ii) The impact of bacteria internalisation by zooplankton was assessed by using C. elegans nematodes as a model host and E. coli as a bacterial target for UVA inactivation. Dispersion of natural aggregates by blending prior to UVA exposure was shown to enhance the inactivation rate of total coliforms as compared to untreated raw water. Removal of particles by an 8-microm membrane filtration did not improve UVA disinfection efficiency. Twenty-four per cent of the highest applied UVA fluence was found to reach internalised E. coli in nematodes. Both aggregation and internalisation showed similar impact as protective mechanisms against UVA and UVC bacterial inactivation.

  14. The Ultraviolet radiation (UV-C for the microbiological stabilization of red wine

    Directory of Open Access Journals (Sweden)

    Matias Fábio

    2016-01-01

    Full Text Available The traditional procedure for the control of the microbiological stability of wine consists of the addition of sulfur dioxide (SO2, which acts as an antimicrobial agent and also as an antioxidant. The search for alternative methods of microbiological control is important and necessary, since SO2 is a potential allergen and consumers are increasingly looking for healthier and preservative free products. Ultraviolet radiation was tested as an innovative technology that can help reduce the amount of sulphur dioxide used in winemaking. The object of this study was to optimize the process conditions compared to the results obtained previously, and to evaluate the efficiency of microbiological stabilization and its influence on the physico-chemical characteristics, the phenolic composition and sensory profile. Thus, red wine with very low content of sulphur dioxide was subjected to UV-C radiation in two different doses 424J/l e 778J/l, and the preparation of a control wine was carried out to which 30 mg/l sulfur dioxide was added. The wines (control=UV0, UV1 and UV2 were analyzed over time (from 0 to 4 months. The results show that treatment with a lower dosage is effective in the microbiological control of the product. The wines subjected to treatment with UV-C showed an increase in intensity of colour, and the treatment does not affect the flavour and taste of the wine.

  15. Evolution of phytoplankton cultures after ultraviolet light treatment

    International Nuclear Information System (INIS)

    Martínez, L.F.; Mahamud, M.M.; Lavín, A.G.; Bueno, J.L.

    2012-01-01

    Introducing invasive species in new environments through ballast water is a specific problem of contamination and has recently become one of the main concerns of Maritime Organizations. Ultraviolet-C radiation (UV-C) is a technological alternative to prevent this maritime pollution. This study addresses the effect of UV-C on different phytoplankton cultures and also the ability to recover following exposure to damage. A UV-C low-pressure lamp irradiates the cultures. The distance from the source and the thickness of the layer prevent part of the energy from reaching the culture and the disinfective process is diminished. Some cultures such as Chlorella autotrophica and Chaetoceros calcitrans can easily recover from UV-C damage. However, Phaeocystis globosa does not have this ability. C. calcitrans forms cysts and exhibits two different behaviours depending on the dose applied.

  16. Furan formation from fatty acids as a result of storage, gamma irradiation, UV-C and heat treatments

    Science.gov (United States)

    Furan is a possible human carcinogen that has been found in many thermally processed foods. The effects of thermal processing, gamma and UV-C irradiation on formation of furan from different fatty acids was studied. In addition, formation of furan from fatty acid emulsions during storage at 25C and...

  17. Mathematical modelling of light-induced electric reaction of Cucurbita pepo L. leaves

    Directory of Open Access Journals (Sweden)

    Jan Stolarek

    2014-01-01

    Full Text Available The bioelectRIc reactions of 14-16 day old plants of pumpkin (Cucurbita pepo L. and internodal cells of Nitellopsis obtusa to the action of visible and ultraviolet light (UV-C were studied. The possibility of analyzing the bioelectric reaction of pumpkin plants induced by visible light by means of mathematical modelling using a linear differential equation of the second order was considered. The solution of this equation (positive and negative functions can, in a sufficient way, reflect the participation of H+ and CI- ions in the generation of the photoelectric response in green plant cells.

  18. Upper Limb Muscle and Brain Activity in Light Assembly Task on Different Load Levels

    Science.gov (United States)

    Zadry, Hilma Raimona; Dawal, Siti Zawiah Md.; Taha, Zahari

    2010-10-01

    A study was conducted to investigate the effect of load on upper limb muscles and brain activities in light assembly task. The task was conducted at two levels of load (Low and high). Surface electromyography (EMG) was used to measure upper limb muscle activities of twenty subjects. Electroencephalography (EEG) was simultaneously recorded with EMG to record brain activities from Fz, Pz, O1 and O2 channels. The EMG Mean Power Frequency (MPF) of the right brachioradialis and the left upper trapezius activities were higher on the high-load task compared to low-load task. The EMG MPF values also decrease as time increases, that reflects muscle fatigue. Mean power of the EEG alpha bands for the Fz-Pz channels were found to be higher on the high-load task compared to low-load task, while for the O1-O2 channels, they were higher on the low-load task than on the high-load task. These results indicated that the load levels effect the upper limb muscle and brain activities. The high-load task will increase muscle activities on the right brachioradialis and the left upper tapezius muscles, and will increase the awareness and motivation of the subjects. Whilst the low-load task can generate drowsiness earlier. It signified that the longer the time and the more heavy of the task, the subjects will be more fatigue physically and mentally.

  19. Placing rooms in the right light. Targeted daylight and optimised artificial lighting help to improve comfort; Raeume ins richtige Licht ruecken. Gezielt eingesetztes Tageslicht und optimierte kuenstliche Beleuchtung helfen, das Wohlbefinden zu verbessern

    Energy Technology Data Exchange (ETDEWEB)

    Durst, Anna

    2012-11-01

    Regardless whether in the office, at home or in school, too little daylight or unfavourable lighting impair visibility in rooms and strain the eyes. Based on the example of schools and homes for the elderly, it was investigated how new lighting concepts and new lamp, luminaire and ballast technology can help to improve the situation. A measurement system was used to monitor the lighting and energy properties. The new lighting systems and optimised technology enabled the electrical energy requirements in a school to be reduced by around two thirds. (orig.)

  20. Determination of 2-alkylcyclobutanones in ultraviolet light-irradiated fatty acids, triglycerides, corn oil, and pork samples: Identifying a new source of 2-alkylcyclobutanones.

    Science.gov (United States)

    Meng, Xiangpeng; Chan, Wan

    2017-02-15

    Previous studies have established that 2-alkylcyclobutanones (2-ACBs) are unique radiolytic products in lipid-containing foods that could only be formed through exposure to ionizing radiation, but not by any other means of physical/heat treatment methods. Therefore, 2-ACBs are currently the marker molecules required by the European Committee for Standardization to be used to identify foods irradiated with ionizing irradiation. Using a spectrum of state-of-the-art analytical instruments, we present in this study for the first time that the generation of 2-ACBs was also possible when fatty acids and triglycerides are exposed to a non-ionizing, short-wavelength ultraviolet (UV-C) light source. An irradiation dosage-dependent formation of 2-ACBs was also observed in UV-C irradiated fatty acids, triglycerides, corn oil, and pork samples. With UV-C irradiation becoming an increasingly common food treatment procedure, it is anticipated that the results from this study will alert food scientists and regulatory officials to a potential new source for 2-ACBs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Mutations induced by ultraviolet light

    International Nuclear Information System (INIS)

    Pfeifer, Gerd P.; You, Young-Hyun; Besaratinia, Ahmad

    2005-01-01

    The different ultraviolet (UV) wavelength components, UVA (320-400 nm), UVB (280-320 nm), and UVC (200-280 nm), have distinct mutagenic properties. A hallmark of UVC and UVB mutagenesis is the high frequency of transition mutations at dipyrimidine sequences containing cytosine. In human skin cancers, about 35% of all mutations in the p53 gene are transitions at dipyrimidines within the sequence 5'-TCG and 5'-CCG, and these are localized at several mutational hotspots. Since 5'-CG sequences are methylated along the p53 coding sequence in human cells, these mutations may be derived from sunlight-induced pyrimidine dimers forming at sequences that contain 5-methylcytosine. Cyclobutane pyrimidine dimers (CPDs) form preferentially at dipyrimidines containing 5-methylcytosine when cells are irradiated with UVB or sunlight. In order to define the contribution of 5-methylcytosine to sunlight-induced mutations, the lacI and cII transgenes in mouse fibroblasts were used as mutational targets. After 254 nm UVC irradiation, only 6-9% of the base substitutions were at dipyrimidines containing 5-methylcytosine. However, 24-32% of the solar light-induced mutations were at dipyrimidines that contain 5-methylcytosine and most of these mutations were transitions. Thus, CPDs forming preferentially at dipyrimidines with 5-methylcytosine are responsible for a considerable fraction of the mutations induced by sunlight in mammalian cells. Using mouse cell lines harboring photoproduct-specific photolyases and mutational reporter genes, we showed that CPDs (rather than 6-4 photoproducts or other lesions) are responsible for the great majority of UVB-induced mutations. An important component of UVB mutagenesis is the deamination of cytosine and 5-methylcytosine within CPDs. The mutational specificity of long-wave UVA (340-400 nm) is distinct from that of the shorter wavelength UV and is characterized mainly by G to T transversions presumably arising through mechanisms involving oxidized DNA

  2. PFP Emergency Lighting Study

    International Nuclear Information System (INIS)

    BUSCH, M.S.

    2000-01-01

    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

  3. Light Water Reactor Sustainability Program A Reference Plan for Control Room Modernization: Planning and Analysis Phase

    Energy Technology Data Exchange (ETDEWEB)

    Jacques Hugo; Ronald Boring; Lew Hanes; Kenneth Thomas

    2013-09-01

    The U.S. Department of Energy’s Light Water Reactor Sustainability (LWRS) program is collaborating with a U.S. nuclear utility to bring about a systematic fleet-wide control room modernization. To facilitate this upgrade, a new distributed control system (DCS) is being introduced into the control rooms of these plants. The DCS will upgrade the legacy plant process computer and emergency response facility information system. In addition, the DCS will replace an existing analog turbine control system with a display-based system. With technology upgrades comes the opportunity to improve the overall human-system interaction between the operators and the control room. To optimize operator performance, the LWRS Control Room Modernization research team followed a human-centered approach published by the U.S. Nuclear Regulatory Commission. NUREG-0711, Rev. 3, Human Factors Engineering Program Review Model (O’Hara et al., 2012), prescribes four phases for human factors engineering. This report provides examples of the first phase, Planning and Analysis. The three elements of Planning and Analysis in NUREG-0711 that are most crucial to initiating control room upgrades are: • Operating Experience Review: Identifies opportunities for improvement in the existing system and provides lessons learned from implemented systems. • Function Analysis and Allocation: Identifies which functions at the plant may be optimally handled by the DCS vs. the operators. • Task Analysis: Identifies how tasks might be optimized for the operators. Each of these elements is covered in a separate chapter. Examples are drawn from workshops with reactor operators that were conducted at the LWRS Human System Simulation Laboratory HSSL and at the respective plants. The findings in this report represent generalized accounts of more detailed proprietary reports produced for the utility for each plant. The goal of this LWRS report is to disseminate the technique and provide examples sufficient to

  4. Room for caring

    DEFF Research Database (Denmark)

    Timmermann, Connie; Uhrenfeldt, Lisbeth; Birkelund, Regner

    2015-01-01

    Aim This study explores how seriously ill hospitalized patients' experience and assign meaning to their patient room. Background Modern hospitals and the rational underlying care and treatment of today have their emphasis on diagnosis, cure and treatment. Consequently, aesthetics in the patient...... rooms such as a view of nature or natural light entering the room are often neglected in caring for these patients. Method A phenomenological-hermeneutic study design was applied and data was collected through multiple qualitative interviews combined with observations at a teaching hospital in Denmark......-being, relief and hope for the patients during serious illness. Therefore, these sensory impressions should be thought of as holding palliative potential and should be included as a part of caring for the seriously ill patients....

  5. Deep Ultraviolet Light Emitters Based on (Al,Ga)N/GaN Semiconductor Heterostructures

    Science.gov (United States)

    Liang, Yu-Han

    Deep ultraviolet (UV) light sources are useful in a number of applications that include sterilization, medical diagnostics, as well as chemical and biological identification. However, state-of-the-art deep UV light-emitting diodes and lasers made from semiconductors still suffer from low external quantum efficiency and low output powers. These limitations make them costly and ineffective in a wide range of applications. Deep UV sources such as lasers that currently exist are prohibitively bulky, complicated, and expensive. This is typically because they are constituted of an assemblage of two to three other lasers in tandem to facilitate sequential harmonic generation that ultimately results in the desired deep UV wavelength. For semiconductor-based deep UV sources, the most challenging difficulty has been finding ways to optimally dope the (Al,Ga)N/GaN heterostructures essential for UV-C light sources. It has proven to be very difficult to achieve high free carrier concentrations and low resistivities in high-aluminum-containing III-nitrides. As a result, p-type doped aluminum-free III-nitrides are employed as the p-type contact layers in UV light-emitting diode structures. However, because of impedance-mismatch issues, light extraction from the device and consequently the overall external quantum efficiency is drastically reduced. This problem is compounded with high losses and low gain when one tries to make UV nitride lasers. In this thesis, we provide a robust and reproducible approach to resolving most of these challenges. By using a liquid-metal-enabled growth mode in a plasma-assisted molecular beam epitaxy process, we show that highly-doped aluminum containing III-nitride films can be achieved. This growth mode is driven by kinetics. Using this approach, we have been able to achieve extremely high p-type and n-type doping in (Al,Ga)N films with high aluminum content. By incorporating a very high density of Mg atoms in (Al,Ga)N films, we have been able to

  6. Transgenerational changes in plant physiology and in transposon expression in response to UV-C stress in Arabidopsis thaliana.

    Science.gov (United States)

    Migicovsky, Zoe; Kovalchuk, Igor

    2014-01-01

    Stress has a negative impact on crop yield by altering a gain in biomass and affecting seed set. Recent reports suggest that exposure to stress also influences the response of the progeny. In this paper, we analyzed seed size, leaf size, bolting time and transposon expression in 2 consecutive generations of Arabidopsis thaliana plants exposed to moderate UV-C stress. Since previous reports suggested a potential role of Dicer-like (DCL) proteins in the establishment of transgenerational response, we used dcl2, dcl3 and dcl4 mutants in parallel with wild-type plants. These studies revealed that leaf number decreased in the progeny of UV-C stressed plants, and bolting occurred later. Transposons were also re-activated in the progeny of stressed plants. Changes in the dcl mutants were less prominent than in wild-type plants. DCL2 and DCL3 appeared to be more important in the transgenerational stress memory than DCL4 because transgenerational changes were less profound in the dcl2 and dcl3 mutants.

  7. Single-cell gel electrophoresis applied to the analysis of UV-C damage and its repair in human cells

    International Nuclear Information System (INIS)

    Gedik, C.M.; Collins, A.R.; Ewen, S.W.B.

    1992-01-01

    The authors have adapted procedure of single cell gel electrophoresis (SCGE) for studying DNA damage and repair induced by UV-C-radiation, using HeLa cells. UV-C itself does not induce DNA breakage, and though cellular repair of UV-C damage produces DNA breaks as intermediates, these are too short-lived to be detected by SCGE. Incubation of UV-C-irradiated cells with the DNA synthesis inhibitor aphidicolin causes accumulation of incomplete repair sites to a level readily detected by SCGE even after doses as low as 0.5 J m -2 and incubation for as little as 5 min. The authors also studied UV-C-dependent incision, repair synthesis and ligation in permeable cells. Finally, key incubated permeable cells, after UV-C-irradiation, with exogenous UV endonuclease, examined consequent breaks both by SCGE and by alkaline unwinding to express results of the electrophoretic method in terms of DNA break frequencies. The sensitivity of the SCGE technique can thus be estimated; as few as 0.1 DNA breaks per 10 9 daltons are detected. (Author)

  8. A room temperature light source based on silicon nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Lo Faro, M.J. [CNR-IPCF, Istituto per i Processi Chimico-Fisici, V. le F. Stagno D' Alcontres 37, 98158 Messina (Italy); MATIS CNR-IMM, Istituto per la Microelettronica e Microsistemi, Via Santa Sofia 64, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania, Via Santa Sofia 64, 95123 Catania (Italy); D' Andrea, C. [MATIS CNR-IMM, Istituto per la Microelettronica e Microsistemi, Via Santa Sofia 64, 95123 Catania (Italy); Messina, E.; Fazio, B. [CNR-IPCF, Istituto per i Processi Chimico-Fisici, V. le F. Stagno D' Alcontres 37, 98158 Messina (Italy); Musumeci, P. [Dipartimento di Fisica e Astronomia, Università di Catania, Via Santa Sofia 64, 95123 Catania (Italy); Franzò, G. [MATIS CNR-IMM, Istituto per la Microelettronica e Microsistemi, Via Santa Sofia 64, 95123 Catania (Italy); Gucciardi, P.G.; Vasi, C. [CNR-IPCF, Istituto per i Processi Chimico-Fisici, V. le F. Stagno D' Alcontres 37, 98158 Messina (Italy); Priolo, F. [MATIS CNR-IMM, Istituto per la Microelettronica e Microsistemi, Via Santa Sofia 64, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania, Via Santa Sofia 64, 95123 Catania (Italy); Scuola Superiore di Catania, Via Valdisavoia 9, 95123 Catania (Italy); Iacona, F. [MATIS CNR-IMM, Istituto per la Microelettronica e Microsistemi, Via Santa Sofia 64, 95123 Catania (Italy); Irrera, A., E-mail: irrera@me.cnr.it [CNR-IPCF, Istituto per i Processi Chimico-Fisici, V. le F. Stagno D' Alcontres 37, 98158 Messina (Italy)

    2016-08-31

    We synthesized ultrathin Si nanowires (NWs) by metal assisted chemical wet etching, using a very thin discontinuous Au layer as precursor for the process. A bright room temperature emission in the visible range due to electron–hole recombination in quantum confined Si NWs is reported. A single walled carbon nanotube (CNT) suspension was prepared and dispersed in Si NW samples. The hybrid Si NW/CNT system exhibits a double emission at room temperature, both in the visible (due to Si NWs) and the IR (due to CNTs) range, thus demonstrating the realization of a low-cost material with promising perspectives for applications in Si-based photonics. - Highlights: • Synthesis of ultrathin Si nanowires (NWs) by metal-assisted chemical etching • Synthesis of NW/carbon nanotube (CNT) hybrid systems • Structural characterization of Si NWs and Si NW/CNT • Room temperature photoluminescence (PL) properties of Si NWs and of Si NW/CNT • Tuning of the PL properties of the Si NW/CNT hybrid system.

  9. UV-C photolysis of endocrine disruptors. The influence of inorganic peroxides

    International Nuclear Information System (INIS)

    Rivas, Javier; Gimeno, Olga; Borralho, Teresa; Carbajo, Maria

    2010-01-01

    Norfloxacin, doxycycline and mefenamic acid have been photolysed with UV-C radiation (254 nm) in the presence and absence of inorganic peroxides (hydrogen peroxide or sodium monopersulfate). Quantum yields in the range (1.1-4.5) x 10 -3 mol Einstein -1 indicate the low photo-reactivity of these pharmaceuticals. Inorganic peroxides considerably enhanced the contaminants conversion, although no appreciable mineralization could be obtained. A simplistic reaction mechanism for the hydrogen peroxide promoted experiments allowed for a rough estimation of the rate constant between hydroxyl radicals and norfloxacin (k > 1 x 10 9 M -1 s -1 ), doxycycline (k > 1.5 x 10 9 M -1 s -1 ) and mefenamic acid (k > 11.0 x 10 9 M -1 s -1 ).

  10. UV-C radiation based methods for aqueous metoprolol elimination

    Energy Technology Data Exchange (ETDEWEB)

    Rivas, F.J., E-mail: fjrivas@unex.es [Departamento de Ingenieria Quimica y Quimica Fisica, Universidad de Extremadura, Facultad de Ciencias, Edificio Jose Luis Sotelo, Avenida de Elvas S/N, 06071 Badajoz (Spain); Gimeno, O.; Borralho, T.; Carbajo, M. [Departamento de Ingenieria Quimica y Quimica Fisica, Universidad de Extremadura, Facultad de Ciencias, Edificio Jose Luis Sotelo, Avenida de Elvas S/N, 06071 Badajoz (Spain)

    2010-07-15

    The endocrine disruptor metoprolol has been oxidised in aqueous solution by means of the systems UV-C, UV-C/H{sub 2}O{sub 2}, UV-C/percarbonate, UV-C/monopersulfate, UV-C/TiO{sub 2}, UV-C/H{sub 2}O{sub 2}/TiO{sub 2} and photo-Fenton. From simple photolysis experiments the quantum yield of metoprolol has been calculated (roughly 5 x 10{sup -3} mol Einstein{sup -1} at circumneutral pH). Addition of free radicals promoters significantly enhanced the metoprolol depletion rate. Mineralization degree was negligible when no promoter was added, while low values were achieved in the presence of either inorganic peroxides or titanium dioxide. The combination of radiation, hydrogen peroxide and TiO{sub 2} increased the mineralization level up to values in the proximity of 45-50% under the best conditions investigated. The photo-Fenton process was the best system in terms of total oxidation (mineralization degree 70%) when optimum conditions were applied.

  11. UV-C radiation based methods for aqueous metoprolol elimination

    International Nuclear Information System (INIS)

    Rivas, F.J.; Gimeno, O.; Borralho, T.; Carbajo, M.

    2010-01-01

    The endocrine disruptor metoprolol has been oxidised in aqueous solution by means of the systems UV-C, UV-C/H 2 O 2 , UV-C/percarbonate, UV-C/monopersulfate, UV-C/TiO 2 , UV-C/H 2 O 2 /TiO 2 and photo-Fenton. From simple photolysis experiments the quantum yield of metoprolol has been calculated (roughly 5 x 10 -3 mol Einstein -1 at circumneutral pH). Addition of free radicals promoters significantly enhanced the metoprolol depletion rate. Mineralization degree was negligible when no promoter was added, while low values were achieved in the presence of either inorganic peroxides or titanium dioxide. The combination of radiation, hydrogen peroxide and TiO 2 increased the mineralization level up to values in the proximity of 45-50% under the best conditions investigated. The photo-Fenton process was the best system in terms of total oxidation (mineralization degree 70%) when optimum conditions were applied.

  12. The effect of UV-C stimulation of potato tubers and soaking of potato strips in water on density differences of intermediates for French-fry production

    Directory of Open Access Journals (Sweden)

    Sobol Zygmunt

    2018-01-01

    Full Text Available The paper describes the effect of UV-C stimulation of potato tubers and immersing of potato strips in water on differences in density of intermediate products for French-fry production. The density difference used for description of the experiment was defined as a relationship between the post-treatment density and pre-treatment density. The study was conducted on tubers of the Innovator variety. The studies of density changes induced by absorption of water involved measurements of the mass of potato strips in air and in water. Potato strips measured 10 × 10 mm and 60 mm in length. The strips were cut lengthwise along the longest tuber axis set between the proximal and distal tuber end. Water absorption was investigated by immersing strips in water (1 at a temperature of 20°C for 15 min and (2 at 40°C for 20 min. In addition, the study included the group (3 where strips were blanched at a temperature of 90°C for 2 min and a control group (0 which was not immersed in water. Potato tubers were irradiated by UV-C in the following ways: (1 irradiation on one side for 30 min, (2 irradiation on both sides for 15 min each, (0 control group (no irradiation. The studies were conducted at two dates: (0 after harvest and (1 after 3-month storage. Laboratory and storage experiments were conducted in 2016-2017. The density difference was statistically significantly influenced by storage time, UV-C stimulation and immersion conditions of potato strips. The density difference increased with the increase in storage duration of tubers, immersion duration of strips, water temperature (up to starch gelification temperature and UV-C stimulation.

  13. Escherichia coli and Cronobacter sakazakii in 'Tommy Atkins' minimally processed mangos: Survival, growth and effect of UV-C and electrolyzed water.

    Science.gov (United States)

    Santo, David; Graça, Ana; Nunes, Carla; Quintas, Célia

    2018-04-01

    These studies were aimed at assessing the growing capacity of Escherichia coli and Cronobacter sakazakii and the effectiveness of Ultraviolet-C (UV-C) radiation, acidic electrolyzed (AEW) and neutral electrolyzed (NEW) waters in the inhibition of these bacteria on minimally processed 'Tommy Atkins' mangoes (MPM). The fruits were contaminated by dip inoculation and kept 10 days at 4, 8, 12 and 20 °C while enumerating bacteria. Contaminated mangoes were disinfected using UV-C (2.5, 5, 7.5 and 10 kJ/m 2 ), AEW, NEW and sodium hypochlorite (SH) and the microorganisms were monitored. None of the enterobacteria grew at 4, 8 and 12 °C regardless of having persisted during the 10-day period. At 20 °C, E. coli and C. sakazakii grew, after adaption phases of 48 h and 24 h, to values of 8.7 and 8.5 log cfu/g at day eight, respectively. E. coli showed the highest reduction counts on the MPM washed with NEW and SH (2.2 log cfu/g). UV-C was more effective in reducing C. sakazakii (2.4-2.6 log cfu/g), when compared to AEW, NEW and SH (1.2-1.8 log cfu/g). The efficacy of decontamination technologies depends on microorganisms, highlighting the importance of preventing contamination at the primary production and of combining different methods to increase the safety of fresh-cut fruits. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Computer vision for shoe upper profile measurement via upper and sole conformal matching

    Science.gov (United States)

    Hu, Zhongxu; Bicker, Robert; Taylor, Paul; Marshall, Chris

    2007-01-01

    This paper describes a structured light computer vision system applied to the measurement of the 3D profile of shoe uppers. The trajectory obtained is used to guide an industrial robot for automatic edge roughing around the contour of the shoe upper so that the bonding strength can be improved. Due to the specific contour and unevenness of the shoe upper, even if the 3D profile is obtained using computer vision, it is still difficult to reliably define the roughing path around the shape. However, the shape of the corresponding shoe sole is better defined, and it is much easier to measure the edge using computer vision. Therefore, a feasible strategy is to measure both the upper and sole profiles, and then align and fit the sole contour to the upper, in order to obtain the best fit. The trajectory of the edge of the desired roughing path is calculated and is then smoothed and interpolated using NURBS curves to guide an industrial robot for shoe upper surface removal; experiments show robust and consistent results. An outline description of the structured light vision system is given here, along with the calibration techniques used.

  15. Video Recording With a GoPro in Hand and Upper Extremity Surgery.

    Science.gov (United States)

    Vara, Alexander D; Wu, John; Shin, Alexander Y; Sobol, Gregory; Wiater, Brett

    2016-10-01

    Video recordings of surgical procedures are an excellent tool for presentations, analyzing self-performance, illustrating publications, and educating surgeons and patients. Recording the surgeon's perspective with high-resolution video in the operating room or clinic has become readily available and advances in software improve the ease of editing these videos. A GoPro HERO 4 Silver or Black was mounted on a head strap and worn over the surgical scrub cap, above the loupes of the operating surgeon. Five live surgical cases were recorded with the camera. The videos were uploaded to a computer and subsequently edited with iMovie or the GoPro software. The optimal settings for both the Silver and Black editions, when operating room lights are used, were determined to be a narrow view, 1080p, 60 frames per second (fps), spot meter on, protune on with auto white balance, exposure compensation at -0.5, and without a polarizing lens. When the operating room lights were not used, it was determined that the standard settings for a GoPro camera were ideal for positioning and editing (4K, 15 frames per second, spot meter and protune off). The GoPro HERO 4 provides high-quality, the surgeon perspective, and a cost-effective video recording of upper extremity surgical procedures. Challenges include finding the optimal settings for each surgical procedure and the length of recording due to battery life limitations. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  16. Pulse on pulse: modulation and signification in Rafael Lozano-Hemmer's Pulse Room

    Directory of Open Access Journals (Sweden)

    Merete Carlson

    2012-06-01

    Full Text Available This article investigates the relation between signifying processes and non-signifying material dynamism in the installation Pulse Room (2006 by Mexican Canadian artist Rafael Lozano-Hemmer. In Pulse Room the sense of pulse is ambiguous. Biorhythms are transmitted from the pulsing energy of the visitor's beating heart to the flashing of a fragile light bulb, thereby transforming each light bulb into a register of individual life. But at the same time the flashing light bulbs together produce a chaotically flickering light environment composed by various layers of repetitive rhythms, a vibrant and pulsating “room”. Hence, the visitor in Pulse Room is invited into a complex scenario that continuously oscillates between various aspects of signification (the light bulbs representing individual lives; the pulse itself as the symbolic “rhythm of life” and instants of pure material processuality (flickering light bulbs; polyrhythmic layers. Taking our point of departure in a discussion of Gilles Deleuze's concepts of modulation and signaletic material in relation to electronic media, we examine how the complex orchestration of pulsation between signification and material modulation produces a multilayered sense of time and space that is central to the sensory experience of Pulse Room as a whole. Pulse Room is, at the very same time, a relational subject–object intimacy and an all-encompassing immersive environment modulating continuously in real space-time.

  17. Inactivation of Uropathogenic Escherichia coli in Ground Chicken Meat Using High Pressure Processing and Gamma Radiation, and in Purge and Chicken Meat Surfaces by Ultraviolet Light

    Directory of Open Access Journals (Sweden)

    Christopher H Sommers

    2016-04-01

    Full Text Available Extraintestinal pathogenic Escherichia coli (ExPEC, including uropathogenic E. coli (UPEC are common contaminants in poultry meat and may cause urinary tract infections after colonization of the gastrointestinal tract and transfer of contaminated feces to the urethra. Three nonthermal processing technologies used to improve the safety and shelf-life of both human and pet foods include high pressure processing (HPP, ionizing (gamma radiation (GR, and ultraviolet light (UV-C. Multi-isolate cocktails of UPEC were inoculated into ground chicken which was then treated with HPP (4 oC, 0-25 min at 300, 400 or 500 MPa. HPP D10, the processing conditions needed to inactivate 1 log of UPEC, was 30.6, 8.37, and 4.43 min at 300, 400, and 500 MPa, respectively. When the UPEC was inoculated into ground chicken and gamma irradiated (4 and -20 oC the GR D10 were 0.28 and 0.36 kGy, respectively. The UV-C D10 of UPEC in chicken suspended in exudate and placed on stainless steel and plastic food contact surfaces ranged from 11.4 to 12.9 mJ/cm2. UV-C inactivated ca. 0.6 log of UPEC on chicken breast meat. These results indicate that existing nonthermal processing technologies such as HPP, GR, and UV-C can significantly reduce UPEC levels in poultry meat or exudate and provide safer poultry products for at-risk consumers.

  18. Inactivation of Uropathogenic Escherichia coli in Ground Chicken Meat Using High Pressure Processing and Gamma Radiation, and in Purge and Chicken Meat Surfaces by Ultraviolet Light.

    Science.gov (United States)

    Sommers, Christopher H; Scullen, O J; Sheen, Shiowshuh

    2016-01-01

    Extraintestinal pathogenic Escherichia coli, including uropathogenic E. coli (UPEC), are common contaminants in poultry meat and may cause urinary tract infections after colonization of the gastrointestinal tract and transfer of contaminated feces to the urethra. Three non-thermal processing technologies used to improve the safety and shelf-life of both human and pet foods include high pressure processing (HPP), ionizing (gamma) radiation (GR), and ultraviolet light (UV-C). Multi-isolate cocktails of UPEC were inoculated into ground chicken which was then treated with HPP (4°C, 0-25 min) at 300, 400, or 500 MPa. HPP D10, the processing conditions needed to inactivate 1 log of UPEC, was 30.6, 8.37, and 4.43 min at 300, 400, and 500 MPa, respectively. When the UPEC was inoculated into ground chicken and gamma irradiated (4 and -20°C) the GR D10 were 0.28 and 0.36 kGy, respectively. The UV-C D10 of UPEC in chicken suspended in exudate and placed on stainless steel and plastic food contact surfaces ranged from 11.4 to 12.9 mJ/cm(2). UV-C inactivated ca. 0.6 log of UPEC on chicken breast meat. These results indicate that existing non-thermal processing technologies such as HPP, GR, and UV-C can significantly reduce UPEC levels in poultry meat or exudate and provide safer poultry products for at-risk consumers.

  19. PS Control Room

    CERN Multimedia

    CERN PhotoLab

    1963-01-01

    The good old PS Control Room, all manual. For each parameter, a knob or a button to control it; for each, a light or meter or oscilloscope to monitor it; carefully written pages serve as the data bank; phones and intercom for communication. D.Dekkers is at the microphone, M.Valvini sits in front.

  20. Teamwork and problem solving in the control room

    International Nuclear Information System (INIS)

    Nygard, F.I.; Dedon, J.M.; Fuld, R.B.

    1989-01-01

    The importance of teamwork and communications in the control room of a nuclear power plant has been the subject of significant attention during the 10 yr since the Three Mile Island accident. The ability to conduct effective problem solving, especially under unexpected conditions, requires that the control room crew be well trained in techniques that produce synergism and avoid ambiguous or conflicting interactions. This paper describes the foundations of a training program developed and conducted by Combustion Engineering to produce a winning team in the control room. The complete licensed operations staffs of three utilities, Florida Power ampersand Light, Louisiana Power ampersand Light, and Omaha Public Power District, have completed this program. Thus, the results of the experience of ∼150 licensed operators is reported

  1. One-step synthesis of lightly doped porous silicon nanowires in HF/AgNO3/H2O2 solution at room temperature

    International Nuclear Information System (INIS)

    Bai, Fan; Li, Meicheng; Song, Dandan; Yu, Hang; Jiang, Bing; Li, Yingfeng

    2012-01-01

    One-step synthesis of lightly doped porous silicon nanowire arrays was achieved by etching the silicon wafer in HF/AgNO 3 /H 2 O 2 solution at room temperature. The lightly doped porous silicon nanowires (pNWs) have circular nanopores on the sidewall, which can emit strong green fluorescence. The surface morphologies of these nanowires could be controlled by simply adjusting the concentration of H 2 O 2 , which influences the distribution of silver nanoparticles (Ag NPs) along the nanowire axis. A mechanism based on Ag NPs-induced lateral etching of nanowires was proposed to explain the formation of pNWs. The controllable and widely applicable synthesis of pNWs will open their potential application to nanoscale photoluminescence devices. - Graphical abstract: The one-step synthesis of porous silicon nanowire arrays is achieved by chemical etching of the lightly doped p-type Si (100) wafer at room temperature. These nanowires exhibit strong green photoluminescence. SEM, TEM, HRTEM and photoluminescence images of pNWs. The scale bars of SEM, TEM HRTEM and photoluminescence are 10 μm, 20 nm, 10 nm, and 1 μm, respectively. Highlights: ► Simple one-step synthesis of lightly doped porous silicon nanowire arrays is achieved at RT. ► Etching process and mechanism are illustrated with etching model from a novel standpoint. ► As-prepared porous silicon nanowire emits strong green fluorescence, proving unique property.

  2. UV-C mutagenesis of Kluyveromyces marxianus NRRL Y-1109 strain for improved anaerobic growth at elevated temperature on pentose and hexose sugars

    Science.gov (United States)

    More robust industrial yeast strains from Kluyveromyces marxianus NRRL Y-1109 and have been produced using UV-C irradiation specifically for anaerobic conversion of lignocellulosic sugar streams to fuel ethanol at elevated temperature (45°C). This type of random mutagenesis offers the possibility o...

  3. Ultraviolet C lethal effect on Brucella melitensis

    International Nuclear Information System (INIS)

    Al-Mariri, A.

    2008-01-01

    The gram-negative bacteria Brucella melitensis was investigated to evaluate its susceptibility to UVC radiation at 254 nm. At an intensity of 18.7 m W/cm 2 of UVC, the time required for in activation of B. melitensis was 240 seconds in both dark and light, whereas it was 120 seconds and 240 seconds in dark and light respectively; at an intensity of 19.5 m W/cm 2 . The results indicate that vaccinal strain of B. melitensis (Rev.1) is more sensitive to UVC than wild B. melitensis strain. (author)

  4. Large magneto-conductance and magneto-electroluminescence in exciplex-based organic light-emitting diodes at room temperature

    Science.gov (United States)

    Ling, Yongzhou; Lei, Yanlian; Zhang, Qiaoming; Chen, Lixiang; Song, Qunliang; Xiong, Zuhong

    2015-11-01

    In this work, we report on large magneto-conductance (MC) over 60% and magneto-electroluminescence (MEL) as high as 112% at room temperature in an exciplex-based organic light-emitting diode (OLED) with efficient reverse intersystem crossing (ISC). The large MC and MEL are individually confirmed by the current density-voltage characteristics and the electroluminescence spectra under various magnetic fields. We proposed that this type of magnetic field effect (MFE) is governed by the field-modulated reverse ISC between the singlet and triplet exciplex. The temperature-dependent MFEs reveal that the small activation energy of reverse ISC accounts for the large MFEs in the present exciplex-based OLEDs.

  5. Laser sheet light flow visualization for evaluating room air flowsfrom Registers

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain S.; Claret, Valerie; Smith, Brian

    2006-04-01

    Forced air heating and cooling systems and whole house ventilation systems deliver air to individual rooms in a house via supply registers located on walls ceilings or floors; and occasionally less straightforward locations like toe-kicks below cabinets. Ideally, the air velocity out of the registers combined with the turbulence of the flow, vectoring of air by register vanes and geometry of register placement combine to mix the supply air within the room. A particular issue that has been raised recently is the performance of multiple capacity and air flow HVAC systems. These systems vary the air flow rate through the distribution system depending on the system load, or if operating in a ventilation rather than a space conditioning mode. These systems have been developed to maximize equipment efficiency, however, the high efficiency ratings do not include any room mixing effects. At lower air flow rates, there is the possibility that room air will be poorly mixed, leading to thermal stratification and reduced comfort for occupants. This can lead to increased energy use as the occupants adjust the thermostat settings to compensate and parts of the conditioned space have higher envelope temperature differences than for the well mixed case. In addition, lack of comfort can be a barrier to market acceptance of these higher efficiency systems To investigate the effect on room mixing of reduced air flow rates requires the measurement of mixing of supply air with room air throughout the space to be conditioned. This is a particularly difficult exercise if we want to determine the transient performance of the space conditioning system. Full scale experiments can be done in special test chambers, but the spatial resolution required to fully examine the mixing problem is usually limited by the sheer number of thermal sensors required. Current full-scale laboratory testing is therefore severely limited in its resolution. As an alternative, we used a water-filled scale model

  6. Room-Temperature and Aqueous-Phase Synthesis of Plasmonic Molybdenum Oxide Nanoparticles for Visible-Light-Enhanced Hydrogen Generation.

    Science.gov (United States)

    Shi, Jiayuan; Kuwahara, Yasutaka; Wen, Meicheng; Navlani-García, Miriam; Mori, Kohsuke; An, Taicheng; Yamashita, Hiromi

    2016-09-06

    A straightforward aqueous synthesis of MoO3-x nanoparticles at room temperature was developed by using (NH4 )6 Mo7 O24 ⋅4 H2 O and MoCl5 as precursors in the absence of reductants, inert gas, and organic solvents. SEM and TEM images indicate the as-prepared products are nanoparticles with diameters of 90-180 nm. The diffuse reflectance UV-visible-near-IR spectra of the samples indicate localized surface plasmon resonance (LSPR) properties generated by the introduction of oxygen vacancies. Owing to its strong plasmonic absorption in the visible-light and near-infrared region, such nanostructures exhibit an enhancement of activity toward visible-light catalytic hydrogen generation. MoO3-x nanoparticles synthesized with a molar ratio of Mo(VI) /Mo(V) 1:1 show the highest yield of H2 evolution. The cycling catalytic performance has been investigated to indicate the structural and chemical stability of the as-prepared plasmonic MoO3-x nanoparticles, which reveals its potential application in visible-light catalytic hydrogen production. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Effect of light on contents of coumarin compounds in shoots of Ruta graveolens L. cultivated in vitro

    Directory of Open Access Journals (Sweden)

    Halina Ekiert

    2014-01-01

    Full Text Available Shoots of Ruta graveolens L. (Rutaceae were cultivated in stationary liquid culture under different light conditions: constant artificial light (900 lx, darkness, constant artificial light (900 ix following irradiation with UV-C light. The contents of five furanocoumarins: psoralen, bergapten, xanthotoxin, isopimpinellin and imperatorin, as well as biogenetic precursor of these metabolites, umbelliferone, were determined by HPLC method in shoots cultivated in vitro and in overground parts of plants growing in open air. It was shown that light conditions, tested in these experiments, significantly influenced contents of the metabolites in shoots cultivated in in vitro culture. Total content of the coumarin compounds in shoots cultivated under constant artificial light (900 lx was equal or higher than in plants growing under natural conditions. Therefore, it is suggested that stationary liquid shoot culture of R. graveolens. can be an alternative source for obtaining biologically active furanocoumarins.

  8. Rational design of 3D inverse opal heterogeneous composite microspheres as excellent visible-light-induced NO2 sensors at room temperature.

    Science.gov (United States)

    Wang, Tianshuang; Yu, Qi; Zhang, Sufang; Kou, Xueying; Sun, Peng; Lu, Geyu

    2018-03-08

    The lower gas sensitivity, humidity dependence of the gas sensing properties, and long recovery times of room-temperature gas sensors severely limit their applications. Herein, to address these issues, a series of 3D inverse opal (IO) In 2 O 3 -ZnO heterogeneous composite microspheres (HCMs) are fabricated by ultrasonic spray pyrolysis (USP) employing self-assembled sulfonated polystyrene (S-PS) spheres as a sacrificial template. The 3D IO In 2 O 3 -ZnO HCMs possess highly ordered 3D inverse opal structures and bimodal (meso-scale and macro-scale) pores, which can provide large accessible surface areas and rapid mass transfer, resulting in enhanced gas sensing characteristics. Furthermore, the 3D IO architecture and n-n heterojunctions can extend the photoabsorption range to the visible light area, effectively prolonging the lifetimes of photo-generated charge carriers, and can increase separation of visible light-generated charges. As a result, the as-prepared 3D IO In 2 O 3 -ZnO HCMs deliver excellent NO 2 sensing performance under visible light irradiation at room temperature, such as high sensitivity (R gas /R air = 54.3 to 5 ppm NO 2 ), low detection limit (250 ppb), fast recovery time (188 s), excellent selectivity and humidity independence. These enhanced photo-electronic gas sensing properties are attributed to the combination of highly ordered 3D IO microspheres and In 2 O 3 -ZnO heterogeneous composites.

  9. Dispersal of Exhaled Air and Personal Exposure in Displacement Ventilated Rooms

    DEFF Research Database (Denmark)

    Bjørn, Erik; Nielsen, Peter Vilhelm

    2002-01-01

    The influence of the human exhalation on flow fields, contaminant distributions, and personal exposures in displacement ventilated rooms is studied together with the effects of physical movement. Experiments are conducted in full-scale test rooms with life-sized breathing thermal manikins....... Numerical simulations support the experiments. Air exhaled through the mouth can lock in a thermally stratified layer, if the vertical temperature gradient in breathing zone height is sufficiently large. With exhalation through the nose, exhaled air flows to the upper part of the room. The exhalation flow...

  10. Study on the main control room design for Hamaoka Unit No.5

    International Nuclear Information System (INIS)

    Tsuruta, Tadakazu; Sakamoto, Minoru; Maruyama, Tohru; Saito, Tadashi

    2000-01-01

    The main control room of nuclear power station is important to operate the power station and to promote public acceptance of nuclear power station. To enhance them, there is an idea of high ceiling control room with a gallery room located in backside middle upper floor. The control room is expected to enhance habitability and to offer visitors the fine view of the control room. In this study, psychological and physiological influence of such a high ceiling control room design on operators was investigated first. And then some human engineering requirements for desirable main control room were identified. A control room (ceiling height: about 5 meters) adequate to the requirements was designed, and finally the validity of the design was verified by means of full mockup model room tests. The results of this study are applied to the main control room design of Hamaoka Nuclear Power Station Unit No.5 (Chubu Electric Power Co., Inc.) (author)

  11. Automated UV-C mutagenesis of Kluyveromyces marxianus NRRL Y-1109 and selection for microaerophilic growth and ethanol production at elevated temperature on biomass sugars

    Science.gov (United States)

    The yeast Kluyveromyces marxianus is a potential microbial catalyst for producing ethanol from lignocellulosic substrates at elevated temperatures. To improve its growth and ethanol yield under anaerobic conditions, K. marxianus NRRL Y-1109 was irradiated with UV-C, and surviving cells were grown a...

  12. Assessment of daylight quality in simple rooms

    DEFF Research Database (Denmark)

    Johnsen, Kjeld; Dubois, Marie-Claude; Sørensen, Karl Grau

    The present report documents the results of a study on daylight conditions in simple rooms of residential buildings. The overall objective of the study was to develop a basis for a method for the assessment of daylight quality in a room with simple geometry and window configurations. As a tool...... in daylighting conditions for a number of lighting parameters. The results gave clear indications of, for instance, which room would be the brightest, under which conditions might glare be a problem and which type of window would yield the greatest luminous variation (or visual interest), etc....

  13. Design and implementation of a microprocessor based room ...

    African Journals Online (AJOL)

    This paper describes the development of a microprocessor based room illumination control system that offers advantage of improved efficiency in the use of electrical energy and reduced cost of electricity over manually controlled lighting systems. This system is developed to regulate the intensity of light from direct current ...

  14. Visible-to-UVC upconversion efficiency and mechanisms of Lu{sub 7}O{sub 6}F{sub 9}:Pr{sup 3+} and Y{sub 2}SiO{sub 5}:Pr{sup 3+} ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Cates, Ezra L. [Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC 29625 (United States); Center for Optical Materials Science and Engineering Technologies, Clemson University, Anderson, SC 29625 (United States); Wilkinson, Angus P. [School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Kim, Jae-Hong, E-mail: jaehong.kim@yale.edu [Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511 (United States)

    2015-04-15

    Visible-to-UVC upconversion (UC) by Pr{sup 3+}-doped materials is a promising candidate for application to sustainable disinfection technologies, including light-activated antimicrobial surfaces and solar water treatment. In this work, we studied Pr{sup 3+} upconversion in an oxyfluoride host system for the first time, employing Lu{sub 7}O{sub 6}F{sub 9}:Pr{sup 3+} ceramics. Compared to the previously studied Y{sub 2}SiO{sub 5}:Pr{sup 3+} reference material, the oxyfluoride host resulted in a 5-fold increase in intermediate state lifetime, likely due to a lower maximum phonon energy; however, only a 60% gain in UC intensity was observed. To explain this discrepancy, luminescence spectral distribution and decay kinetics were studied in both phosphor systems. The Pr{sup 3+} 4f5d band energy distribution in each phosphor was found to play a key role by allowing or disallowing the occurrence of a previously unexplored UC mechanism, which had a significant impact on overall efficiency. - Highlights: • Visible-to-UVC upconversion by Pr{sup 3+} was studied in an oxyfluoride host matrix for the first time. • Lu{sub 7}O{sub 6}F{sub 9}:Pr{sup 3+} ceramics were synthesized and characterized. • Lu{sub 7}O{sub 6}F{sub 9}:Pr{sup 3+} shows more intense UV upconversion than Y{sub 2}SiO{sub 5}:Pr{sup 3+}, with differing mechanisms. • 4f5d band energy and {sup 1}D{sub 2} involvement are important in maximizing upconversion efficiency.

  15. Multiomics in Grape Berry Skin Revealed Specific Induction of the Stilbene Synthetic Pathway by Ultraviolet-C Irradiation1

    Science.gov (United States)

    Suzuki, Mami; Nakabayashi, Ryo; Ogata, Yoshiyuki; Sakurai, Nozomu; Tokimatsu, Toshiaki; Goto, Susumu; Suzuki, Makoto; Jasinski, Michal; Martinoia, Enrico; Otagaki, Shungo; Matsumoto, Shogo; Saito, Kazuki; Shiratake, Katsuhiro

    2015-01-01

    Grape (Vitis vinifera) accumulates various polyphenolic compounds, which protect against environmental stresses, including ultraviolet-C (UV-C) light and pathogens. In this study, we looked at the transcriptome and metabolome in grape berry skin after UV-C irradiation, which demonstrated the effectiveness of omics approaches to clarify important traits of grape. We performed transcriptome analysis using a genome-wide microarray, which revealed 238 genes up-regulated more than 5-fold by UV-C light. Enrichment analysis of Gene Ontology terms showed that genes encoding stilbene synthase, a key enzyme for resveratrol synthesis, were enriched in the up-regulated genes. We performed metabolome analysis using liquid chromatography-quadrupole time-of-flight mass spectrometry, and 2,012 metabolite peaks, including unidentified peaks, were detected. Principal component analysis using the peaks showed that only one metabolite peak, identified as resveratrol, was highly induced by UV-C light. We updated the metabolic pathway map of grape in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database and in the KaPPA-View 4 KEGG system, then projected the transcriptome and metabolome data on a metabolic pathway map. The map showed specific induction of the resveratrol synthetic pathway by UV-C light. Our results showed that multiomics is a powerful tool to elucidate the accumulation mechanisms of secondary metabolites, and updated systems, such as KEGG and KaPPA-View 4 KEGG for grape, can support such studies. PMID:25761715

  16. Effects of activity inhomogeneities in walls on the external gamma doses in rooms

    Energy Technology Data Exchange (ETDEWEB)

    Feher, I; Andrasi, A; Koblinger, L; Zombori, P; Szabo, P P [Hungarian Academy of Sciences, Budapest. Central Research Inst. for Physics

    1984-01-01

    The effects of activity inhomogeneities in the walls of a room on the free-in-air and spherical phantom doses are investigated. Calculations and measurements are carried out in a room where the ratios of the activity concentrations in the upper layer of the ceiling and floor are as large as 20 and 6, for the Ra and Th chains, respectively.

  17. Tritium Room Air Monitor Operating Experience Review

    Energy Technology Data Exchange (ETDEWEB)

    L. C. Cadwallader; B. J. Denny

    2008-09-01

    Monitoring the breathing air in tritium facility rooms for airborne tritium is a radiological safety requirement and a best practice for personnel safety. Besides audible alarms for room evacuation, these monitors often send signals for process shutdown, ventilation isolation, and cleanup system actuation to mitigate releases and prevent tritium spread to the environment. Therefore, these monitors are important not only to personnel safety but also to public safety and environmental protection. This paper presents an operating experience review of tritium monitor performance on demand during small (1 mCi to 1 Ci) operational releases, and intentional airborne inroom tritium release tests. The tritium tests provide monitor operation data to allow calculation of a statistical estimate for the reliability of monitors annunciating in actual tritium gas airborne release situations. The data show a failure to operate rate of 3.5E-06/monitor-hr with an upper bound of 4.7E-06, a failure to alarm on demand rate of 1.4E-02/demand with an upper bound of 4.4E-02, and a spurious alarm rate of 0.1 to 0.2/monitor-yr.

  18. Justification of Natural Lighting Management for Workplaces with Displays

    Science.gov (United States)

    Kudryashov, A. V.; Erunova, A. V.; Kalinina, A. S.

    2017-11-01

    The article is devoted to the study of the influence of the orientation of light apertures (windows) on the distribution of illumination in a room inside the workplaces equipped with displays. The measurements of natural light were carried out in two similar rooms, in the first room the windows are oriented to the north and in the second - to the south. The normative illumination value in a workplace equipped with a personal computer or display must be between 300 and 500 lux. However, during the daytime, the value of natural illumination at the workplace can exceed the normalized value by several times, and in the morning and evening hours is not sufficient. Such distribution of illumination involves the use a combined lighting control system (with daylight time control and switching on artificial lighting in the morning and evening hours). In the article it is justified that the orientation of the windows in the room does not have a significant effect on the distribution of illumination throughout the room which makes it possible not to take into account the restrictions concerning the orientation of the room’s light apertures when combined lighting control systems are used.

  19. Photoreactivation and dark repair of environmental E. coli strains following 24 kHz continuous ultrasound and UV-C irradiation.

    Science.gov (United States)

    Kaur, Jasjeet; Karthikeyan, Raghupathy; Pillai, Suresh D

    2016-07-02

    In this study, effects of 24 kHz continuous ultrasound and UV-C on inactivation and potential repair of environmental E. coli strains were studied through a culture based method and a metabolic activity assay. Three environmental E. coli strains isolated from fecal samples of feral hog and deer and treated wastewater effluent were studied and compared with a laboratory E. coli strain (ATCC® 10798). Metabolic activity of E. coli cells during the inactivation and repair period was assessed using the AlamarBlue® assay. Transmission electron microscopy assays were also performed to evaluate morphological damage of bacterial cell wall. After 24 h of photoreactivation period, laboratory E. coli strain (ATCC® 10798) reactivated by 30% and 42% in contrast to E. coli isolate from treated wastewater effluent, which reactivated by 53% and 82% after ultrasound and UV-C treatment, respectively. Possible shearing and reduction in cell size of E. coli strains exposed to ultrasound was revealed by transmission electron micrographs. Metabolic activity of E. coli strains was greatly reduced due to morphological damage to cell membrane caused by 24 kHz continuous ultrasound. Based upon experimental data and TEM micrographs, it could be concluded that ultrasound irradiation has potential in advanced water treatment and water reuse applications.

  20. Numerical investigation of upper-room UVGI disinfection efficacy in an environmental chamber with a ceiling fan.

    Science.gov (United States)

    Zhu, Shengwei; Srebric, Jelena; Rudnick, Stephen N; Vincent, Richard L; Nardell, Edward A

    2013-01-01

    This study investigated the disinfection efficacy of the upper-room ultraviolet germicidal irradiation (UR-UVGI) system with ceiling fans. The investigation used the steady-state computational fluid dynamics (CFD) simulations to solve the rotation of ceiling fan with a rotating reference frame. Two ambient air exchange rates, 2 and 6 air changes per hour (ACH), and four downward fan rotational speeds, 0, 80, 150 and 235 rpm were considered. In addition, the passive scalar concentration simulations incorporated ultraviolet (UV) dose by two methods: one based on the total exposure time and average UV fluence rate, and another based on SVE3* (New Scale for Ventilation Efficiency 3), originally defined to evaluate the mean age of the air from an air supply opening. Overall, the CFD results enabled the evaluation of UR-UVGI disinfection efficacy using different indices, including the fraction of remaining microorganisms, equivalent air exchange rate, UR-UVGI effectiveness and tuberculosis infection probability by the Wells-Riley equation. The results indicated that air exchange rate was the decisive factor for determining UR-UVGI performance in disinfecting indoor air. Using a ceiling fan could also improve the performance in general. Furthermore, the results clarified the mechanism for the ceiling fan to influence UR-UVGI disinfection efficacy. © 2013 The Authors Photochemistry and Photobiology © 2013 The American Society of Photobiology.

  1. Light and skin disease

    International Nuclear Information System (INIS)

    Bauer, R.

    1991-01-01

    Because of the depletion of ozone in the stratosphere due to chlorofluorocarbons, the screening effect of this ozone layer on ultraviolet radiation (especially the so-called UV-B component) is reduced. This paper describes the impact of increased UV radiation on the human skin. Because of the 'ozone-hole', a distinct increase in the rate of skin cancer is to be expected which will affect all living beings but most of all man - an indirect consequence of the climate development. What makes the increased intensity of UV-B radiation so harmful is the fact that light-induced skin damage accumulates for the period of the life-time of the individual and cannot be reversed. A further thinning of stratospheric ozone would let through, in addition, the more short-waved ('harder') UV-C radiation. The latter, though clinically not significant currently, would then account for a further increase in the rate of malignant skin disease world-wide. (orig.) [de

  2. Stability of disposal rooms during waste retrieval

    International Nuclear Information System (INIS)

    Brandshaug, T.

    1989-03-01

    This report presents the results of a numerical analysis to determine the stability of waste disposal rooms for vertical and horizontal emplacement during the period of waste retrieval. It is assumed that waste retrieval starts 50 years after the initial emplacement of the waste, and that access to and retrieval of the waste containers take place through the disposal rooms. It is further assumed that the disposal rooms are not back-filled. Convective cooling of the disposal rooms in preparation for waste retrieval is included in the analysis. Conditions and parameters used were taken from the Nevada Nuclear Waste Storage Investigation (NNWSI) Project Site Characterization Plan Conceptual Design Report (MacDougall et al., 1987). Thermal results are presented which illustrate the heat transfer response of the rock adjacent to the disposal rooms. Mechanical results are presented which illustrate the predicted distribution of stress, joint slip, and room deformations for the period of time investigated. Under the assumption that the host rock can be classified as ''fair to good'' using the Geomechanics Classification System (Bieniawski, 1974), only light ground support would appear to be necessary for the disposal rooms to remain stable. 23 refs., 28 figs., 2 tabs

  3. Magnetically modulated electroluminescence from hybrid organic/inorganic light-emitting diodes based on electron donor-acceptor exciplex blends

    Science.gov (United States)

    Pang, Zhiyong; Baniya, Sangita; Zhang, Chuang; Sun, Dali; Vardeny, Z. Valy

    2016-03-01

    We report room temperature magnetically modulated electroluminescence from a hybrid organic/inorganic light-emitting diode (h-OLED), in which an inorganic magnetic tunnel junction (MTJ) with large room temperature magnetoresistance is coupled to an N,N,N ',N '-Tetrakis(4-methoxyphenyl)benzidine (MeO-TPD): tris-[3-(3-pyridyl)mesityl]borane (3TPYMB) [D-A] based OLED that shows thermally activated delayed luminescence. The exciplex-based OLED provides two spin-mixing channels: upper energy channel of polaron pairs and lower energy channel of exciplexes. In operation, the large resistance mismatch between the MTJ and OLED components is suppressed due to the non-linear I-V characteristic of the OLED. This leads to enhanced giant magneto-electroluminescence (MEL) at room temperature. We measured MEL of ~ 75% at ambient conditions. Supported by SAMSUNG Global Research Outreach (GRO) program, and also by the NSF-Material Science & Engineering Center (MRSEC) program at the University of Utah (DMR-1121252).

  4. Point-of-use water disinfection using ultraviolet and visible light-emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Lui, Gough Yumu, E-mail: gough@student.unsw.edu.au [UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); School of Photovoltaics and Renewable Energy Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Roser, David, E-mail: djroser@unsw.edu.au [UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Corkish, Richard, E-mail: r.corkish@unsw.edu.au [School of Photovoltaics and Renewable Energy Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Ashbolt, Nicholas J., E-mail: ashbolt@ualberta.ca [UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); School of Public Health, South Academic Building, University of Alberta, Edmonton, Alberta T6G 2G7 (Canada); Stuetz, Richard, E-mail: r.stuetz@unsw.edu.au [UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052 (Australia)

    2016-05-15

    Improvements in point-of-use (POU) drinking water disinfection technologies for remote and regional communities are urgently needed. Conceptually, UV-C light-emitting diodes (LEDs) overcome many drawbacks of low-pressure mercury tube based UV devices, and UV-A or visible light LEDs also show potential. To realistically evaluate the promise of LED disinfection, our study assessed the performance of a model 1.3 L reactor, similar in size to solar disinfection bottles. In all, 12 different commercial or semi-commercial LED arrays (270–740 nm) were compared for their ability to inactivate Escherichia coli K12 ATCC W3110 and Enterococcus faecalis ATCC 19433 over 6 h. Five log{sub 10} and greater reductions were consistently achieved using the 270, 365, 385 and 405 nm arrays. The output of the 310 nm array was insufficient for useful disinfection while 430 and 455 nm performance was marginal (≈ 4.2 and 2.3-log{sub 10}s E. coli and E. faecalis over the 6 h). No significant disinfection was observed with the 525, 590, 623, 660 and 740 nm arrays. Delays in log-phase inactivation of E. coli were observed, particularly with UV-A wavelengths. The radiation doses required for > 3-log{sub 10} reduction of E. coli and E. faecalis differed by 10 fold at 270 nm but only 1.5–2.5 fold at 365–455 nm. Action spectra, consistent with the literature, were observed with both indicators. The design process revealed cost and technical constraints pertaining to LED electrical efficiency, availability and lifetime. We concluded that POU LED disinfection using existing LED technology is already technically possible. UV-C LEDs offer speed and energy demand advantages, while UV-A/violet units are safer. Both approaches still require further costing and engineering development. Our study provides data needed for such work. - Highlights: • Disinfection of E. coli and E. faecalis achieved with 270 and 365–455 nm LEDs • No significant disinfection was found with 310 and > 455 nm LEDs

  5. Point-of-use water disinfection using ultraviolet and visible light-emitting diodes

    International Nuclear Information System (INIS)

    Lui, Gough Yumu; Roser, David; Corkish, Richard; Ashbolt, Nicholas J.; Stuetz, Richard

    2016-01-01

    Improvements in point-of-use (POU) drinking water disinfection technologies for remote and regional communities are urgently needed. Conceptually, UV-C light-emitting diodes (LEDs) overcome many drawbacks of low-pressure mercury tube based UV devices, and UV-A or visible light LEDs also show potential. To realistically evaluate the promise of LED disinfection, our study assessed the performance of a model 1.3 L reactor, similar in size to solar disinfection bottles. In all, 12 different commercial or semi-commercial LED arrays (270–740 nm) were compared for their ability to inactivate Escherichia coli K12 ATCC W3110 and Enterococcus faecalis ATCC 19433 over 6 h. Five log_1_0 and greater reductions were consistently achieved using the 270, 365, 385 and 405 nm arrays. The output of the 310 nm array was insufficient for useful disinfection while 430 and 455 nm performance was marginal (≈ 4.2 and 2.3-log_1_0s E. coli and E. faecalis over the 6 h). No significant disinfection was observed with the 525, 590, 623, 660 and 740 nm arrays. Delays in log-phase inactivation of E. coli were observed, particularly with UV-A wavelengths. The radiation doses required for > 3-log_1_0 reduction of E. coli and E. faecalis differed by 10 fold at 270 nm but only 1.5–2.5 fold at 365–455 nm. Action spectra, consistent with the literature, were observed with both indicators. The design process revealed cost and technical constraints pertaining to LED electrical efficiency, availability and lifetime. We concluded that POU LED disinfection using existing LED technology is already technically possible. UV-C LEDs offer speed and energy demand advantages, while UV-A/violet units are safer. Both approaches still require further costing and engineering development. Our study provides data needed for such work. - Highlights: • Disinfection of E. coli and E. faecalis achieved with 270 and 365–455 nm LEDs • No significant disinfection was found with 310 and > 455 nm LEDs. • UV-C

  6. Air Distribution in Rooms with a Fan-Driven Convector

    DEFF Research Database (Denmark)

    Larsen, Tine Steen; Bindels, Rob H.W.; Michalak, Lukasz

    2007-01-01

    the acceptable conditions for the supplyJlow rate and the temperature difference for the convector system. The paper shows that the air distribution from the convector results in comfortable velocity and temperature conditions with a heat load of 210 W. This is also confirmed by the draft ratings, which in all...... coming from the dijfuser is partly controlled by the momentum flow and partly from gravity forces, where the thermal load in the room and the temperature difference between room air and supply air affect the airflow from the convector. The convector system was tested in the same test room in which many......Experiments with a fan-driven convector used for both heating and cooling are de.scribed in this paper. Only the cooling situation is considered. The convector is positioned in the upper corner ofthe room, and from there the cold air is let out through the device along the ceiling. The airflow...

  7. Design And Implementation Of Smart Living Room Wireless Control For Safety Purpose

    OpenAIRE

    Aeindra Myint Lwin; Zaw Min Min Htun; Hla Myo Tun

    2015-01-01

    Abstract This research presents the microcontroller controlled smart living room system using Bluetooth wireless technology from mobile phone.An android apk is created in mobile for controlling the living room system. A 16F877A microcontroller is interfaced serially to a bluetooth module transceiver. It is used for controlling fan speed control dim light control lighting ONOFF and window angle control. An arduino controller is used for keypad control door security. It is connected to DC motor...

  8. Lighting, sleep and circadian rhythm: An intervention study in the intensive care unit.

    Science.gov (United States)

    Engwall, Marie; Fridh, Isabell; Johansson, Lotta; Bergbom, Ingegerd; Lindahl, Berit

    2015-12-01

    Patients in an intensive care unit (ICU) may risk disruption of their circadian rhythm. In an intervention research project a cycled lighting system was set up in an ICU room to support patients' circadian rhythm. Part I aimed to compare experiences of the lighting environment in two rooms with different lighting environments by lighting experiences questionnaire. The results indicated differences in advantage for the patients in the intervention room (n=48), in perception of daytime brightness (p=0.004). In nighttime, greater lighting variation (p=0.005) was found in the ordinary room (n=52). Part II aimed to describe experiences of lighting in the room equipped with the cycled lighting environment. Patients (n=19) were interviewed and the results were presented in categories: "A dynamic lighting environment", "Impact of lighting on patients' sleep", "The impact of lighting/lights on circadian rhythm" and "The lighting calms". Most had experiences from sleep disorders and half had nightmares/sights and circadian rhythm disruption. Nearly all were pleased with the cycled lighting environment, which together with daylight supported their circadian rhythm. In night's actual lighting levels helped patients and staff to connect which engendered feelings of calm. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Light sheet microscopy reveals more gradual light attenuation in light green versus dark green soybean leaves

    Science.gov (United States)

    Light wavelengths preferentially absorbed by chlorophyll (chl) often display steep absorption gradients. This oversaturates photosynthesis in upper chloroplasts and deprives lower chloroplasts of blue and red light, causing a steep gradient in carbon fixation. Reducing chl content could create a mor...

  10. Light contamination during the dark phase in "photoperiodically controlled" animal rooms: effect on tumor growth and metabolism in rats.

    Science.gov (United States)

    Dauchy, R T; Sauer, L A; Blask, D E; Vaughan, G M

    1997-10-01

    Enhanced neoplastic growth and metabolism have been reported in animals maintained in a constant light (24L:0D) environment. Results from this laboratory indicate that tumor growth is directly dependent upon increased ambient blood concentrations of arachidonic and linoleic acids, particularly linoleic acid. Tumor linoleic acid utilization and production if its putative mitogenic metabolite, 13-hydroxyoctadecadienoic acid (13-HODE), are suppressed by the circadian neurohormone melatonin, the production of which is itself regulated by light in all mammals. This study was performed to determine whether minimal light contamination (0.2 lux) in an animal room during an otherwise normal dark phase may disrupt normal circadian production of melatonin and affect tumor growth and metabolism. Animals of groups I (12L:12D), II (12L:12-h light-contaminated dark phase), and III (24L:0D) had plasma total fatty acid (TFA), linoleic acid (LA), and melatonin concentrations measured prior to tumor implantation; groups I and II had daily cycles in plasma TFA and LA values, whereas group III had constant values throughout the day. The integrated mean TFA and LA values for the entire day were similar in all groups. Although group-I animals had a normal nocturnal surge of melatonin (127.0 pg/ml) at 2400 h, the nocturnal amplitude was suppressed in group-II animals (16.0 pg/ml); circadian variation in melatonin concentration was not seen in group-III animals (7.4 pg/ml). At 12 weeks of age, rats had the Morris hepatoma 7288CTC implanted as "tissue-isolated" tumors grown subcutaneously. Latency to onset of palpable tumor mass for groups I, II, and III was 11, 9, and 5 days respectively. Tumor growth rates were 0.72 +/- 0.09, 1.30 +/- 0.15, and 1.48 +/- 0.17 g/d (mean +/- SD, n = 6/group) in groups I, II, and III respectively. Arteriovenous difference measurements for TFA and LA across the tumors were 4.22 +/- 0.89 and 0.83 +/- 0.18 (group I), 8.26 +/- 0.66 and 1.64 +/- 0.13 (group II

  11. A Research Framework for Demonstrating Benefits of Advanced Control Room Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Le Blanc, Katya [Idaho National Lab. (INL), Idaho Falls, ID (United States); Boring, Ronald [Idaho National Lab. (INL), Idaho Falls, ID (United States); Joe, Jeffrey [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hallbert, Bruce [Idaho National Lab. (INL), Idaho Falls, ID (United States); Thomas, Kenneth [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-12-01

    Control Room modernization is an important part of life extension for the existing light water reactor fleet. None of the 99 currently operating commercial nuclear power plants in the U.S. has completed a full-scale control room modernization to date. A full-scale modernization might, for example, entail replacement of all analog panels with digital workstations. Such modernizations have been undertaken successfully in upgrades in Europe and Asia, but the U.S. has yet to undertake a control room upgrade of this magnitude. Instead, nuclear power plant main control rooms for the existing commercial reactor fleet remain significantly analog, with only limited digital modernizations. Previous research under the U.S. Department of Energy’s Light Water Reactor Sustainability Program has helped establish a systematic process for control room upgrades that support the transition to a hybrid control. While the guidance developed to date helps streamline the process of modernization and reduce costs and uncertainty associated with introducing digital control technologies into an existing control room, these upgrades do not achieve the full potential of newer technologies that might otherwise enhance plant and operator performance. The aim of the control room benefits research presented here is to identify previously overlooked benefits of modernization, identify candidate technologies that may facilitate such benefits, and demonstrate these technologies through human factors research. This report serves as an outline for planned research on the benefits of greater modernization in the main control rooms of nuclear power plants.

  12. A Research Framework for Demonstrating Benefits of Advanced Control Room Technologies

    International Nuclear Information System (INIS)

    Le Blanc, Katya; Boring, Ronald; Joe, Jeffrey; Hallbert, Bruce; Thomas, Kenneth

    2014-01-01

    Control Room modernization is an important part of life extension for the existing light water reactor fleet. None of the 99 currently operating commercial nuclear power plants in the U.S. has completed a full-scale control room modernization to date. A full-scale modernization might, for example, entail replacement of all analog panels with digital workstations. Such modernizations have been undertaken successfully in upgrades in Europe and Asia, but the U.S. has yet to undertake a control room upgrade of this magnitude. Instead, nuclear power plant main control rooms for the existing commercial reactor fleet remain significantly analog, with only limited digital modernizations. Previous research under the U.S. Department of Energy's Light Water Reactor Sustainability Program has helped establish a systematic process for control room upgrades that support the transition to a hybrid control. While the guidance developed to date helps streamline the process of modernization and reduce costs and uncertainty associated with introducing digital control technologies into an existing control room, these upgrades do not achieve the full potential of newer technologies that might otherwise enhance plant and operator performance. The aim of the control room benefits research presented here is to identify previously overlooked benefits of modernization, identify candidate technologies that may facilitate such benefits, and demonstrate these technologies through human factors research. This report serves as an outline for planned research on the benefits of greater modernization in the main control rooms of nuclear power plants.

  13. Influence of indium tin oxide electrodes deposited at room temperature on the properties of organic light-emitting devices

    International Nuclear Information System (INIS)

    Satoh, Toshikazu; Fujikawa, Hisayoshi; Taga, Yasunori

    2005-01-01

    The influence of indium tin oxide (ITO) electrodes deposited at room temperature (ITO-RT) on the properties of organic light-emitting devices (OLEDs) has been studied. The OLED on the ITO-RT showed an obvious shorter lifetime and higher operating voltage than that on the conventional ITO electrode deposited at 573 K. The result of an in situ x-ray photoelectron spectroscopy analysis of the ITO electrode and the organic layer suggested that many of the hydroxyl groups that originate in the amorphous structure of the ITO-RT electrode oxidize the organic layer. The performance of the OLED on the ITO-RT is able to be explained by the oxidation of the organic layer

  14. A new Main Control Room for the AGS complex

    International Nuclear Information System (INIS)

    Ingrassia, P.F.; Zaharatos, R.M.; Dyling, O.H.

    1991-01-01

    A new Main Control Room (MCR) has been built to control the accelerators of the AGS Complex. A new physical environment was produced to better control light, sound, temperature, and traffic. New control consoles were built around the work-stations that make up the distributed control system. Equipment placement within consoles and console placement within the room reflect attention to the 'human factors' needs of the operator

  15. Microwave discharge electrodeless lamps (MDEL). III. A novel tungsten-triggered MDEL device emitting VUV and UVC radiation for use in wastewater treatment.

    Science.gov (United States)

    Horikoshi, Satoshi; Miura, Takashi; Kajitani, Masatsugu; Serpone, Nick

    2008-03-01

    Exposure to low doses of the xenoestrogen bisphenol A (BPA) and to the hormonal 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide, an environmental endocrine disruptor, can have serious health consequences such as the induction of mammary gland ductal hyperplasias and carcinoma (LaChapelle et al., Reprod. Toxicol., 2007, 23, 20; Murray et al., Reprod. Toxicol., 2007, 23, 383). To the extent that these toxins are present in wastewaters (Donald et al., Sci. Total Environ. 1999, 231, 173; Brotons et al., Environ. Health Perspect. 1994, 103, 608; Olea et al., Environ. Health Perspect. 1996, 104, 298; Biles et al., J. Agric. Food Chem. 1997, 45, 3541; Markey et al., J. Steroid Biochem. Mol. Biol., 2003, 83, 235), we examined their oxidative destruction in aqueous media by a novel light source. A tungsten-triggered microwave discharge electrodeless lamp (W-MDEL) was fabricated for possible use in wastewater treatment using vacuum UV-transparent quartz in which a tungsten trigger, also embedded in quartz, was attached to the MDEL to aid in the self-ignition of the lamp on irradiation at low microwave power levels. The quantity of mercury gas in the W-MDEL was optimized by monitoring the continuous radiation and peak intensities of the emitted light in the vacuum UV (VUV) and UVC regions. The usefulness of the W-MDEL device was assessed through the degradation of 2,4-D and BPA in air-equilibrated aqueous media and in oxygen-saturated aqueous media. Enhanced degradation of these two xenoestrogenic toxins was achieved by increasing the number of W-MDEL devices while keeping constant the microwave radiation feeding each W-MDEL lamp. This novel lamp provides an additional light source in the photooxidation of environmental contaminants without the need for a metal-oxide photocatalyst. Under our conditions, process dynamics using the W-MDEL light source are greater than with the more conventional photochemical methods that employ low-pressure Hg arc electrode lamps in synthetic

  16. Ultraviolet light in the use of water disinfection

    International Nuclear Information System (INIS)

    Dabbagh, R.

    1999-01-01

    . Transparent materials for UV-C in the nature is very low. Except quartz and pure water, two kind of materials, glass and polymers, were studied in this research. Experiments carried out PIXE analysis method to get special glass ingradiants and another method was measuring UV transmittances through the materials. Ultraviolet rays absorbed in the ordinary glass caused the presence of different materials oxide especially ferric oxide (Fe 2 O 3 ). PIXE analysis shows that there is very low amount of ferric oxide with very high amount of silica in the high silica glass. Teflon, Polyethylene and Polypropylene films are polymers which have very good transmittances for UV-C region. There is 30-80 percent transmittances for Teflon group in the 0.2-0.9 mm thickness. Teflons don't get destroyed against destructive effect UV-C light. For polyethylene and polypropylene films in 0.12mm thickness, transmittances was 78 and 83 percent in ordered

  17. Efficient charge carrier injection into sub-250 nm AlGaN multiple quantum well light emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Mehnke, Frank, E-mail: mehnke@physik.tu-berlin.de; Kuhn, Christian; Guttmann, Martin; Reich, Christoph; Kolbe, Tim; Rass, Jens; Wernicke, Tim [Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstr. 36, EW 6-1, 10623 Berlin (Germany); Kueller, Viola; Knauer, Arne; Lapeyrade, Mickael; Einfeldt, Sven; Weyers, Markus [Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany); Kneissl, Michael [Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstr. 36, EW 6-1, 10623 Berlin (Germany); Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany)

    2014-08-04

    The design and Mg-doping profile of AlN/Al{sub 0.7}Ga{sub 0.3}N electron blocking heterostructures (EBH) for AlGaN multiple quantum well (MQW) light emitting diodes (LEDs) emitting below 250 nm was investigated. By inserting an AlN electron blocking layer (EBL) into the EBH, we were able to increase the quantum well emission power and significantly reduce long wavelength parasitic luminescence. Furthermore, electron leakage was suppressed by optimizing the thickness of the AlN EBL while still maintaining sufficient hole injection. Ultraviolet (UV)-C LEDs with very low parasitic luminescence (7% of total emission power) and external quantum efficiencies of 0.19% at 246 nm have been realized. This concept was applied to AlGaN MQW LEDs emitting between 235 nm and 263 nm with external quantum efficiencies ranging from 0.002% to 0.93%. After processing, we were able to demonstrate an UV-C LED emitting at 234 nm with 14.5 μW integrated optical output power and an external quantum efficiency of 0.012% at 18.2 A/cm{sup 2}.

  18. Efficient charge carrier injection into sub-250 nm AlGaN multiple quantum well light emitting diodes

    International Nuclear Information System (INIS)

    Mehnke, Frank; Kuhn, Christian; Guttmann, Martin; Reich, Christoph; Kolbe, Tim; Rass, Jens; Wernicke, Tim; Kueller, Viola; Knauer, Arne; Lapeyrade, Mickael; Einfeldt, Sven; Weyers, Markus; Kneissl, Michael

    2014-01-01

    The design and Mg-doping profile of AlN/Al 0.7 Ga 0.3 N electron blocking heterostructures (EBH) for AlGaN multiple quantum well (MQW) light emitting diodes (LEDs) emitting below 250 nm was investigated. By inserting an AlN electron blocking layer (EBL) into the EBH, we were able to increase the quantum well emission power and significantly reduce long wavelength parasitic luminescence. Furthermore, electron leakage was suppressed by optimizing the thickness of the AlN EBL while still maintaining sufficient hole injection. Ultraviolet (UV)-C LEDs with very low parasitic luminescence (7% of total emission power) and external quantum efficiencies of 0.19% at 246 nm have been realized. This concept was applied to AlGaN MQW LEDs emitting between 235 nm and 263 nm with external quantum efficiencies ranging from 0.002% to 0.93%. After processing, we were able to demonstrate an UV-C LED emitting at 234 nm with 14.5 μW integrated optical output power and an external quantum efficiency of 0.012% at 18.2 A/cm 2

  19. A new main control room for the AGS complex

    International Nuclear Information System (INIS)

    Ingrassia, P.F.; Zaharatos, R.M.; Dyling, O.H.

    1991-01-01

    A new Main Control Room (MCR) has been built to control the accelerators of the AGS Complex. A new physical environment was produced to better control light, sound, temperature, and traffic. New control consoles were built around the work-stations that make up the distributed control system. Equipment placement within consoles and console placement within the room reflect attention to the ''human factors'' needs of the operator. 1 ref., 2 figs

  20. Effects of garlic on cellular doubling time and DNA strand breaks caused by UV light and BPL, enhanced with catechol and TPA

    International Nuclear Information System (INIS)

    Baturay, N.Z.; Gayle, F.; Liu, S.; Kreidinger, C.

    1995-01-01

    3T3 cell cultures were exposed to UV light and Beta-Propiolactone. Neoplastic cell transformation (TF) was demonstrated after concurrent addition of catechol, or repeated addition of TPA. Addition of garlic to all fluences/concentrations of the carcinogen/cocarcinogen/promoter groups reduced the number of transformed foci/dish by at least 40%. Since the cell cycle is prolonged following exposure to carcinogens, it is likely the cell requires a longer time to repair this damage. The doubling time (DT) was extended from 12 to 36 hrs. when cells were exposed to BPL and from 12 o 28 hrs. when cells were exposed to 3.0J/M2/sec. If an anticarcinogenic compound is also added, it is reasonable to assume that the cell cycle may be further elongated. The cell cycle, denoted by DT was lengthened from 12 to 47 hrs and from 12 to 86 hrs for BPL and UVC, respectively. The extensions occurred in a dope dependent manner. The concentrations of the cocarcinogen and promoter remained constant throughout the experiment. When strand breaks were determined at the same dose sequences, by alkaline elution, more repair was seen with garlic where the lowest and middle doses of BPL were used and almost no decrease in % DNA eluted was seen with UVC exposed cells. With catechol, there was a two-fold decrease in % DNA eluted at the lowest and middle fluences. When TPA was added, all three fluences of UVC showed more than a threefold decrease in % DNA eluted. BPS with both TPA and catechol, again showed a reduction in strand breaks only low and middle doses. Both a direct-acting alkylating agent, BPL, and a physical carcinogen, UVC, were homogeneously affected, in terms of doubling time, but not when strand break repair was examined. A separate mechanism may be responsible for repair, and the mechanism associated with combinations of physical carcinogen enhancing agents combined with some non-carcinogens may be more profoundly affected by some natural products

  1. The impact of morning light intensity and environmental temperature on body temperatures and alertness.

    Science.gov (United States)

    Te Kulve, Marije; Schlangen, Luc J M; Schellen, Lisje; Frijns, Arjan J H; van Marken Lichtenbelt, Wouter D

    2017-06-01

    Indoor temperature and light exposure are known to affect body temperature, productivity and alertness of building occupants. However, not much is known about the interaction between light and temperature exposure and the relationship between morning light induced alertness and its effect on body temperature. Light intensity and room temperature during morning office hours were investigated under strictly controlled conditions. In a randomized crossover study, two white light conditions (4000K, either bright 1200lx or dim 5lx) under three different room temperatures (26, 29 and 32°C) were investigated. A lower room temperature increased the core body temperature (CBT) and lowered skin temperature and the distal-proximal temperature gradient (DPG). Moreover, a lower room temperature reduced the subjective sleepiness and reaction time on an auditory psychomotor vigilance task (PVT), irrespective of the light condition. Interestingly, the morning bright light exposure did affect thermophysiological parameters, i.e. it decreased plasma cortisol, CBT and proximal skin temperature and increased the DPG, irrespective of the room temperature. During the bright light session, subjective sleepiness decreased irrespective of the room temperature. However, the change in sleepiness due to the light exposure was not related to these physiological changes. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. A prototype catheter designed for ultraviolet C disinfection

    DEFF Research Database (Denmark)

    Bak, Jimmy; Begovic, Tanja

    2013-01-01

    UVC light exposure, sampling and plate counting. Findings Two minutes of UVC exposure was sufficient to obtain 4 log10 disinfection for the full-length prototype catheter. This exposure corresponds to ∼40 mJ/cm2 at the catheter tip and indicates that even shorter exposure times can be achieved...

  3. 20 CFR 654.410 - Electricity and lighting.

    Science.gov (United States)

    2010-04-01

    ... RESPONSIBILITIES OF THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.410 Electricity and lighting. (a) All housing sites shall be provided with electric service. (b) Each habitable room and all common use rooms, and areas such as: Laundry rooms, toilets, privies, hallways, stairways...

  4. Light and energy - daylight measurements

    Energy Technology Data Exchange (ETDEWEB)

    Christoffersen, Jens; Logadottir, A.; Traberg-Borup, S.; Barrie-Nielsen, K.

    2009-07-01

    All measurements where conducted in the spring of 2007, except the Interpane panel. The solar cell panels have been evaluated by three performance indicators to assess the daylight quantity within the room and the systems ability to maintain view to the outside. In the study, we used two performance indicators to assess the daylight quantity within the room: 1. the daylight factor (overcast sky) 2. the relative work plane illuminance (clear sky condition) Overcast sky: In general, all panels provided less daylight than the recommended requirement in the Danish Building Regulation of 2% on the work plane. This will most likely result in additional need for electric lighting. However, larger window areas and more parts of the facade with clear unobstructed glass may be one solution. Clear sky: In general, all panels provided less interior light levels than the two reference systems in the back of the room. Almost all systems aloud more or less direct sunlight in the window perimeter through the clear openings and additional needs for some kind of shading device is to be expected. Some systems blocked a large portion of the light in the majority of the room, and additional electric light in this part of the room may be needed. Only one performance indicator where used to describe the quality of the panels. View: In general, all panels, except two, obstruct the view significantly and cause figure/background confusion for a view position close to the window and the discrepancies of colour judgements. Only two systems provided a fairly clear view to the outside without to much distortion of the view. (au)

  5. Red-light-emitting laser diodes operating CW at room temperature

    Science.gov (United States)

    Kressel, H.; Hawrylo, F. Z.

    1976-01-01

    Heterojunction laser diodes of AlGaAs have been prepared with threshold current densities substantially below those previously achieved at room temperature in the 7200-8000-A spectral range. These devices operate continuously with simple oxide-isolated stripe contacts to 7400 A, which extends CW operation into the visible (red) portion of the spectrum.

  6. Primary aortojejunal fistula: a rare cause for massive upper gastrointestinal bleeding.

    Science.gov (United States)

    Paulasir, Sylvester; Khorfan, Rhami; Harsant, Christina; Anderson, Harry Linne

    2017-04-26

    A 68-year-old man presented to the emergency department with haematemesis and shock. Upper endoscopy and selective angiography could not identify the source of bleeding. He underwent selective embolisation of the gastroduodenal artery. The patient then had a period of about 24 hours with relative haemodynamic stability before having another episode of massive upper gastrointestinal bleed. A second attempt to embolise the common hepatic artery and distal coeliac axis was unsuccessful. Hence, he was urgently taken to the operating room for exploratory laparotomy. The source of bleeding could not be identified in the operating room. The patient went into cardiac arrest and expired. Autopsy revealed a fistula between proximal jejunum and a previously unknown abdominal aortic aneurysm (AAA). We present an entity that has only been described a few times in the literature while highlighting the importance of having a broad differential with upper gastrointestinal bleeding, especially when the source is not clearly evident. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  7. Light + architecture. Daylight - artificial light - energy; Licht + Architektur. Tageslicht - Kunstlicht - Energie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    The symposium intends to provide scientific and technical fundamentals for room lighting with daylight. Daylight deflection systems and artificial light control systems were analyzed for this purpose, and a catalogue of criteria was established. Planners were given tools for projecting daylight control systems. Builder-owners received the fundamentals for economic assessment of combined daylight and artificial light illumination systems, while industrial producers obtained information for further development to maturity and for marketing of daylight-dependent artificial light control systems. (GL)

  8. Red-light-emitting laser diodes operating cw at room temperature

    International Nuclear Information System (INIS)

    Kressel, H.; Hawrylo, F.Z.

    1976-01-01

    Heterojunction laser diodes of AlGaAs have been prepared with threshold current densities substantially below those previously achieved at room temperature in the 7200 to 8000-A spectral range. These devices operate cw with simple oxide-isolated stripe contacts to 7400 A, which extends cw operation for the first time into the visible (red) portion of the spectrum

  9. Strong violet-blue light photoluminescence emission at room temperature in SrZrO3: Joint experimental and theoretical study

    International Nuclear Information System (INIS)

    Longo, V.M.; Cavalcante, L.S.; Erlo, R.; Mastelaro, V.R.; Figueiredo, A.T. de; Sambrano, J.R.; Lazaro, S. de; Freitas, A.Z.; Gomes, L.; Vieira, N.D.; Varela, J.A.; Longo, Elson

    2008-01-01

    Ultrafine ordered and disordered SrZrO 3 powders were prepared by the polymeric precursor method. The structural evolution from structural disorder to order was monitored by X-ray diffraction and X-ray absorption near-edge spectroscopy. Complex cluster vacancies [ZrO 5 .V O Z ]and[SrO 11 .V O Z ] (where V O Z =V O X , V O · andV O ·· ) were proposed for disordered powders. The intense violet-blue light photoluminescence emission measured at room temperature in the disordered powders was attributed to complex cluster vacancies. High-level quantum mechanical calculations within the density functional theory framework were used to interpret the experimental results

  10. Effects of light-emitting diode light v. fluorescent light on growing performance, activity levels and well-being of non-beak-trimmed W-36 pullets.

    Science.gov (United States)

    Liu, K; Xin, H; Settar, P

    2018-01-01

    More energy-efficient, readily dimmable, long-lasting and more affordable light-emitting diode (LED) lights are increasingly finding applications in poultry production facilities. Despite anecdotal evidence about the benefits of such lighting on bird performance and behavior, concrete research data were lacking. In this study, a commercial poultry-specific LED light (dim-to-blue, controllable correlated color temperature (CCT) from 4500 to 5300 K) and a typical compact fluorescent light (CFL) (soft white, CCT=2700 K) were compared with regards to their effects on growing performance, activity levels, and feather and comb conditions of non-beak-trimmed W-36 pullets during a 14-week rearing period. A total of 1280-day-old pullets in two successive batches, 640 birds each, were used in the study. For each batch, pullets were randomly assigned to four identical litter-floor rooms equipped with perches, two rooms per light regimen, 160 birds per room. Body weight, BW uniformity (BWU), BW gain (BWG) and cumulative mortality rate (CMR) of the pullets were determined every 2 weeks from day-old to 14 weeks of age (WOA). Activity levels of the pullets at 5 to 14 WOA were delineated by movement index. Results revealed that pullets under the LED and CFL lights had comparable BW (1140±5 g v. 1135±5 g, P=0.41), BWU (90.8±1.0% v. 91.9±1.0%, P=0.48) and CMR (1.3±0.6% v. 2.7±0.6%, P=0.18) at 14 WOA despite some varying BWG during the rearing. Circadian activity levels of the pullets were higher under the LED light than under the CFL light, possibly resulting from differences in spectrum and/or perceived light intensity between the two lights. No feather damage or comb wound was apparent in either light regimen at the end of the rearing period. The results contribute to understanding the impact of emerging LED lights on pullets rearing which is a critical component of egg production.

  11. Analysis of bacterial contamination on surface of general radiography equipment and CT equipment in emergency room of radiology

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Dong Hee; KIm, Hyeong Gyun [Dept. of Radiological Science, Far East University, Eumseong (Korea, Republic of)

    2016-09-15

    We aim to offer basic materials about infection management through conducting bacterial contamination test about general radiography equipment and CT equipment installed in ER of three general hospitals with 100 sickbeds or more located in Gyeongsangbuk-do Province, and suggest management plan. It had been conducted from 1st December 2015 to 31st December, and objects were general radiography equipment and CT equipment of emergency room located in Gyeongsangbuk-do Province. For general radiography equipment, sources were collected from 4 places such as upper side of control box which employees use most, upper side of exposure button, whole upper side of table which is touching part of patient's skin, upper side of stand bucky's grid, and where patients put their jaws on. For CT equipment, sources were collected from 3 places such as upper side of control box which radiography room employees use most, X-ray exposure button, whole upper side of table which is touching part of patient's skin, and gantry inner. Surface contamination strain found at general radiography equipment in emergency room of radiology are Providencia stuartii(25%), Stenotrophomonas maltophilia(18%), Enterobacter cloacae(8%), Pseudomonas species(8%), Staphylococcus epidermidis(8%), Gram negative bacilli(8%), and ungrown bacteria at incubator after 48 hours of incubation (67%) which is the biggest. Most bacteria were found at upper side of stand bucky-grid and stand bucky of radiology's general radiography equipment, and most sources of CT equipment were focused at patient table, which means it is contaminated by patients who have various diseases, and patients who have strains with decreased immunity may get severe diseases. Thus infection prevention should be made through 70% alcohol disinfection at both before test and after test.

  12. Analysis of bacterial contamination on surface of general radiography equipment and CT equipment in emergency room of radiology

    International Nuclear Information System (INIS)

    Hong, Dong Hee; KIm, Hyeong Gyun

    2016-01-01

    We aim to offer basic materials about infection management through conducting bacterial contamination test about general radiography equipment and CT equipment installed in ER of three general hospitals with 100 sickbeds or more located in Gyeongsangbuk-do Province, and suggest management plan. It had been conducted from 1st December 2015 to 31st December, and objects were general radiography equipment and CT equipment of emergency room located in Gyeongsangbuk-do Province. For general radiography equipment, sources were collected from 4 places such as upper side of control box which employees use most, upper side of exposure button, whole upper side of table which is touching part of patient's skin, upper side of stand bucky's grid, and where patients put their jaws on. For CT equipment, sources were collected from 3 places such as upper side of control box which radiography room employees use most, X-ray exposure button, whole upper side of table which is touching part of patient's skin, and gantry inner. Surface contamination strain found at general radiography equipment in emergency room of radiology are Providencia stuartii(25%), Stenotrophomonas maltophilia(18%), Enterobacter cloacae(8%), Pseudomonas species(8%), Staphylococcus epidermidis(8%), Gram negative bacilli(8%), and ungrown bacteria at incubator after 48 hours of incubation (67%) which is the biggest. Most bacteria were found at upper side of stand bucky-grid and stand bucky of radiology's general radiography equipment, and most sources of CT equipment were focused at patient table, which means it is contaminated by patients who have various diseases, and patients who have strains with decreased immunity may get severe diseases. Thus infection prevention should be made through 70% alcohol disinfection at both before test and after test

  13. Perception of tomorrow's nuclear power plant control rooms

    International Nuclear Information System (INIS)

    Meyer, O.R.

    1986-01-01

    Major development programs are upgrading today's light water reactor nuclear power plant (NPP) control rooms. These programs involve displays, control panel architecture, procedures, staffing, and training, and are supported by analytical efforts to refine the definitions of the dynamics and the functional requirements of NPP operation. These programs demonstrate that the NPP control room is the visible command/control/communications center of the complex man/machine system that operates the plant. These development programs are primarily plant specific, although the owners' groups and the Institute of Nuclear Power Operations (INPO) do provide some standardization. The Idaho National Engineering Laboratory recently completed a project to categorize control room changes and estimate the degree of change. That project, plus related studies, provides the basis for this image of the next generation of NPP control rooms. The next generation of NPP control rooms is envisioned as being dominated by three current trends: (1) application of state-of-the-art computer hardware and software; (2) use of NPP dynamic analyses to provide the basis for the control room man/machine system design; and (3) application of empirical principles of human performance

  14. Efficacy of an automated ultraviolet C device in a shared hospital bathroom.

    Science.gov (United States)

    Cooper, Jesse; Bryce, Elizabeth; Astrakianakis, George; Stefanovic, Aleksandra; Bartlett, Karen

    2016-12-01

    Toilet flushing can contribute to disease transmission by generating aerosolized bacteria and viruses that can land on nearby surfaces or follow air currents. Aerobic and anaerobic bacterial bioaerosol loads, and bacterial counts on 2 surfaces in a bathroom with a permanently installed, automated ultraviolet C (UVC) irradiation device, were significantly lower than in a comparable bathroom without the UVC device. Permanently installed UVC lights may be a useful supplementary decontamination tool in shared patient bathrooms. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  15. Tuning the light in senior care: Evaluating a trial LED lighting system at the ACC Care Center in Sacramento, CA

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Robert G.; Wilkerson, Andrea M.; Samla, Connie; Bisbee, Dave

    2016-08-31

    This report summarizes the results from a trial installation of light-emitting diode (LED) lighting systems in several spaces within the ACC Care Center in Sacramento, CA. The Sacramento Municipal Utility District (SMUD) coordinated the project and invited the U.S. Department of Energy (DOE) to document the performance of the LED lighting systems as part of a GATEWAY evaluation. DOE tasked the Pacific Northwest National Laboratory (PNNL) to conduct the investigation. SMUD and ACC staff coordinated and completed the design and installation of the LED systems, while PNNL and SMUD staff evaluated the photometric performance of the systems. ACC staff also track behavioral and health measures of the residents; some of those results are reported here, although PNNL staff were not directly involved in collecting or interpreting those data. The trial installation took place in a double resident room and a single resident room, and the corridor that connects those (and other) rooms to the central nurse station. Other spaces in the trial included the nurse station, a common room called the family room located near the nurse station, and the ACC administrator’s private office.

  16. Room temperature femtosecond X-ray diffraction of photosystem II microcrystals

    Science.gov (United States)

    Kern, Jan; Alonso-Mori, Roberto; Hellmich, Julia; Tran, Rosalie; Hattne, Johan; Laksmono, Hartawan; Glöckner, Carina; Echols, Nathaniel; Sierra, Raymond G.; Sellberg, Jonas; Lassalle-Kaiser, Benedikt; Gildea, Richard J.; Glatzel, Pieter; Grosse-Kunstleve, Ralf W.; Latimer, Matthew J.; McQueen, Trevor A.; DiFiore, Dörte; Fry, Alan R.; Messerschmidt, Marc; Miahnahri, Alan; Schafer, Donald W.; Seibert, M. Marvin; Sokaras, Dimosthenis; Weng, Tsu-Chien; Zwart, Petrus H.; White, William E.; Adams, Paul D.; Bogan, Michael J.; Boutet, Sébastien; Williams, Garth J.; Messinger, Johannes; Sauter, Nicholas K.; Zouni, Athina; Bergmann, Uwe; Yano, Junko; Yachandra, Vittal K.

    2012-01-01

    Most of the dioxygen on earth is generated by the oxidation of water by photosystem II (PS II) using light from the sun. This light-driven, four-photon reaction is catalyzed by the Mn4CaO5 cluster located at the lumenal side of PS II. Various X-ray studies have been carried out at cryogenic temperatures to understand the intermediate steps involved in the water oxidation mechanism. However, the necessity for collecting data at room temperature, especially for studying the transient steps during the O–O bond formation, requires the development of new methodologies. In this paper we report room temperature X-ray diffraction data of PS II microcrystals obtained using ultrashort (< 50 fs) 9 keV X-ray pulses from a hard X-ray free electron laser, namely the Linac Coherent Light Source. The results presented here demonstrate that the ”probe before destroy” approach using an X-ray free electron laser works even for the highly-sensitive Mn4CaO5 cluster in PS II at room temperature. We show that these data are comparable to those obtained in synchrotron radiation studies as seen by the similarities in the overall structure of the helices, the protein subunits and the location of the various cofactors. This work is, therefore, an important step toward future studies for resolving the structure of the Mn4CaO5 cluster without any damage at room temperature, and of the reaction intermediates of PS II during O–O bond formation. PMID:22665786

  17. Uso de la radiación UV-C en el proceso de elaboración de hortalizas de IV gama

    OpenAIRE

    Gutiérrez, Diego; Ruiz López, Gustavo; Sgroppo, Sonia; Rodríguez, Silvia

    2016-01-01

    Uno de los principales factores que limita la vida útil de las hortalizas frescas es el crecimiento de microorganismos durante el almacenamiento refrigerado. Es por ello que durante la etapa de procesamiento de hortalizas de IV gama siempre se incluye una etapa de lavado y sanitización para reducir la contaminación microbiana inicial. El uso de radiación ultravioleta artificial (UV) a una longitud de onda de 190 a 280 nm (UV-C) tiene poder germicida y puede ser eficaz para la descontaminación...

  18. Control room concept for remote maintenance in high radiation areas

    International Nuclear Information System (INIS)

    Clarke, M.M.; Kreifeldt, J.G.

    1984-01-01

    This paper summarizes the design of a control room concept for an operator interface with remote maintenance equipment consisting of force-reflecting manipulators, tools, hoists, cranes, cameras, and lights. The design development involved two major activities. First, detailed requirements were defined for foreseeable functions that will be performed by the control room operators. Second, concepts were developed, tested, and refined to meet these requirements. 6 references, 3 figures

  19. Development of the Concept of Recycling of Light

    Science.gov (United States)

    Harmer, Brian

    Environmental and economic issues are the highlights of any new product or system created today. The efficient use of energy helps satisfy both of these concerns as a reduction in energy consumption contributes to a reduction both in fuel consumption and carbon emissions. Illumination efficiency has been one of the main areas of research as luminaires are one of the largest consumers of electricity in the world. The incandescent bulb is one of the oldest pieces of technology still used today, but is being phased out as compact fluorescent lamps and LED light sources have a much lower power consumption for the same amount of light emission. However, the light source design, while very important, is not the only way to improve the efficiency of an illumination system. This thesis proposes a new concept, the recycling of light (ROL). The ROL system collects, transports, and emits unused light from one area to another through the use of optical fibers. To find an optimal ROL system, many variables need to be accounted for. This thesis covers the effect of different luminaires on light collection areas. The collection area for the ROL system needs to be placed in the areas of a room that are of little or no importance, but still receive light, such as the ceiling or the upper section of the walls. The fiber-to-source distance and offset effects on fiber emission are investigated, as well as the length and type of the optical fibers. Additionally, this thesis looks at the possibility of beveling optical fiber ends to be used as a focusing mechanism for the ROL system.

  20. CdS/TiO{sub 2} nanocomposite film and its enhanced photoelectric responses to dry air and formaldehyde induced by visible light at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Zhijun, E-mail: zjzou@xynu.edu.cn [Key Laboratory of Advanced Micro/Nano Functional Materials, Department of Physics and Electronic Engineering, Xinyang Normal University, Xinyang 464000 (China); State Key Laboratory of Material Processing and Die & Mould Technology, Nanomaterials and Smart Sensors Research Laboratory, Department of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Qiu, Yang [Key Laboratory of Advanced Micro/Nano Functional Materials, Department of Physics and Electronic Engineering, Xinyang Normal University, Xinyang 464000 (China); Xie, Changsheng [State Key Laboratory of Material Processing and Die & Mould Technology, Nanomaterials and Smart Sensors Research Laboratory, Department of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Xu, Jingjing; Luo, Yongsong; Wang, Chunlei; Yan, Hailong [Key Laboratory of Advanced Micro/Nano Functional Materials, Department of Physics and Electronic Engineering, Xinyang Normal University, Xinyang 464000 (China)

    2015-10-05

    Highlights: • Photoelectric responses of TiO{sub 2} and CdS/TiO{sub 2} to dry air and formaldehyde were tested. • In contrary to TiO{sub 2}, photoelectric response of CdS/TiO{sub 2} obviously increased. • CdS/TiO{sub 2} nanocomposite device exhibits excellent stability to formaldehyde. • CdS/TiO{sub 2} may be a promising material for developing high performance sensor. - Abstract: Photoelectric responses of pure TiO{sub 2} and CdS/TiO{sub 2} nanocomposite devices to dry air and formaldehyde under visible light irradiation at room temperature were investigated in this work. The pure TiO{sub 2} film was firstly prepared by screen printing and CdS/TiO{sub 2} nanocomposite film by the subsequent SILAR process. XRD, FE-SEM, HR-TEM and UV–vis DRS analysis were employed to examine the fundamental characteristics of as-prepared samples. Photoelectric responses of pure TiO{sub 2} device displayed that no obvious photocurrent was observed upon turning the visible light on either in dry air or in formaldehyde. But in contrary to pure TiO{sub 2} device, the photoelectric response of CdS/TiO{sub 2} nanocomposite device has been obviously enhanced. It is the adding of CdS, which works as a sensitizer, that accounts for the enhanced response and makes the CdS/TiO{sub 2} device sensitive to the visible light. Moreover, the CdS/TiO{sub 2} nanocomposite device exhibits excellent stability to formaldehyde. The present work does not only shed light on the photoelectric gas sensing properties of TiO{sub 2} and CdS/TiO{sub 2}, but also suggests that the CdS/TiO{sub 2} nanocomposite may be a promising material for fabricating visible-light-induced photoelectric gas sensors working at room temperature.

  1. Combined Effects of Blue and Ultraviolet Lights on the Accumulation of Flavonoids in Tartary Buckwheat Sprouts

    Directory of Open Access Journals (Sweden)

    Ji Hongbin

    2016-06-01

    Full Text Available The effects of blue and UV-A (365 nm/UV-C (254 nm or their combinations on the levels of total flavonoids, rutin, quercetin, phenylalanine ammonialyase (PAL, chalcone isomerase (CHI, rutin degrading enzymes (RDEs and 1,1-diphenyl-2-picrylhydrazyl (DPPH radical scavenging activity in tartary buckwheat sprouts were investigated in this study. The total flavonoids content in the tartary buckwheat sprouts irradiated with blue light followed by UV-C (BL+UV-C raised by 10%, compared with the opposite combination sequence (UV-C+BL. However, blue light did not show the same results when combined with UV-A, and their combinations on the accumulation of total flavonoids were still lower than that of UV-A/UV-C. Key enzymes (PAL, CHI and RDEs revealed a significant correlation with total flavonoids in tartary buckwheat sprouts.

  2. Man and room climate. The importance of thermal comfort; Der Mensch und das Raumklima. Zur Bedeutung der thermischen Behaglichkeit

    Energy Technology Data Exchange (ETDEWEB)

    Hoefte, Klaus [Uponor Academy, Ochtrup (Germany)

    2009-07-01

    Room climate has become increasingly important during the past few decades as humans spend about 90 percent of their time inside rooms. Influencing factors are acoustics, lighting, air quality and thermal room climate. The contribution focuses on thermal room climate and room air quality which are the most important of these factors. (orig.)

  3. Control room concept for remote maintenance in high radiation areas

    International Nuclear Information System (INIS)

    Clarke, M.M.; Kreifeldt, J.G.

    1984-01-01

    This paper summarizes the design of a control room concept for an operator interface with remote maintenance equipment consisting of force-reflecting manipulators, tools, hoists, cranes, cameras, and lights. The design development involved two major activities. First, detailed requirements were defined for foreseeable functions that will be performed by the control room operators. Second, concepts were developed, tested, and refined to meet these requirements. Each of these activities is summarized below. 6 references, 3 figures

  4. Light and architecture. Daylight - artificial light - energy; Licht und Architektur. Tageslicht - Kunstlicht - Energie

    Energy Technology Data Exchange (ETDEWEB)

    Wambsganss, M. (ed.) [ip5 ingenieurpartnerschaft, Karlsruhe (Germany)]|[Fachhochschule Rosenheim (Germany)

    2007-07-01

    The symposium intends to provide scientific and technical fundamentals for room lighting with daylight. Daylight deflection systems and artificial light control systems were analyzed for this purpose, and a catalogue of criteria was established. Planners were given tools for projecting daylight control systems. Builder-owners received the fundamentals for economic assessment of combined daylight and artificial light illumination systems, while industrial producers obtained information for further development to maturity and for marketing of daylight-dependent artificial light control systems. (GL)

  5. Saving energy by overriding automatic lighting control: A case study

    NARCIS (Netherlands)

    Lelkens, A.

    2011-01-01

    Modern office buildings are often equipped with automatic systems that turn on the lights if somebody enters a room and turn them off when everybody has left the room. This ensures that users do not leave the lights on during the night and thus avoids wasting energy. For cost reasons, most of these

  6. Degradation effects of the active region in UV-C light-emitting diodes

    Science.gov (United States)

    Glaab, Johannes; Haefke, Joscha; Ruschel, Jan; Brendel, Moritz; Rass, Jens; Kolbe, Tim; Knauer, Arne; Weyers, Markus; Einfeldt, Sven; Guttmann, Martin; Kuhn, Christian; Enslin, Johannes; Wernicke, Tim; Kneissl, Michael

    2018-03-01

    An extensive analysis of the degradation characteristics of AlGaN-based ultraviolet light-emitting diodes emitting around 265 nm is presented. The optical power of LEDs stressed at a constant dc current of 100 mA (current density = 67 A/cm2 and heatsink temperature = 20 °C) decreased to about 58% of its initial value after 250 h of operation. The origin of this degradation effect has been studied using capacitance-voltage and photocurrent spectroscopy measurements conducted before and after aging. The overall device capacitance decreased, which indicates a reduction of the net charges within the space-charge region of the pn-junction during operation. In parallel, the photocurrent at excitation energies between 3.8 eV and 4.5 eV and the photocurrent induced by band-to-band absorption in the quantum barriers at 5.25 eV increased during operation. The latter effect can be explained by a reduction of the donor concentration in the active region of the device. This effect could be attributed to the compensation of donors by the activation or diffusion of acceptors, such as magnesium dopants or group-III vacancies, in the pn-junction space-charge region. The results are consistent with the observed reduction in optical power since deep level acceptors can also act as non-radiative recombination centers.

  7. UV-vis light transmittance through tinted contact lenses and the effect of color on values.

    Science.gov (United States)

    Osuagwu, Uchechukwu L; Ogbuehi, Kelechi C

    2014-06-01

    To assess the transmittance, in the 200-700nm electromagnetic radiation spectrum, by popularly used tinted soft contact lenses (CLs). The spectra transmittances of ultraviolet (UV)-blocking (I Day Acuvue Define, Freshlook ONE DAY) and non-UV-blocking (Durasoft 3, Tutti, and NeoCosmo) tinted soft CLs were tested. The transmittance of each lens, including nine different colors of Freshlook CL was recorded on spectrophotometer, and the data used to also calculate a UV protection factor (PF) for each lens brand tested, with a higher value indicating a higher level of protection. The UV-blocking CLs significantly reduced UVC, UVB & UVA transmission and thereby meet the American National Standards Institution standard for class 2 UV blockers: a maximum of 30% transmittance of UVA and 5% transmittance of UVB wavelengths. In contrast, the Durasoft 3, Tutti, and NeoCosmo CLs demonstrated negligible UV-blockage. The Acuvue Define CL offered the greatest protection from UVC (PF=69) and UVB (PF=55), but with only 35% luminous transmittance, while the Freshlook CL (especially gemstone green) offered the best protection from UVA (PF=24) and showed about 55% translucency. Overall, the UV-blocking CLs performed equally well across the UV spectrum. Different colors of Freshlook CL transmitted statistically and clinically significantly different amounts of visible light but similar amounts of UVR. Freshlook and Acuvue Define CLs which are designated as UV-blockers significantly reduced UVR transmission to safe levels whereas Tutti, NeoCosmo and Durasoft 3 did not. Transmission within the Freshlook CL family was more dependent on color in the visible light spectrum, but not in the UV-spectrum, where the gemstone green performing best among the tested colors. Copyright © 2013 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  8. Effect of single varied doses of UV-C radiation on photosynthesis, traspiration and chlorophyll content in the leaves of two varieties of faba bean and pea

    International Nuclear Information System (INIS)

    Olszewski, J.; Pszczolkowska, A.

    2004-01-01

    The effect of single, varied (75, 120 and 165 min) UV-C radiation on photosynthesis and transpiration in leaves of two morphotypes of faba bean and pea was determined in a pot experiment. The SPAD leaf greenness index, which characterises the a and b chlorophyll contents (as well as changes in its content caused by radiation) were analysed. The experimental results indicated that the intensity of photosynthesis and transpiration in faba bean leaves was higher in the plants treated with the UV-C radiation. In addition, the intensity of photosynthesis and the chlorophyll content were higher in the Neptun variety than in the self-terminating faba bean variety. The Rola pea variety plants showed a significant decrease in photsynthesis intensity under radiation in the 3rd leaf phase and a slight decrease in later developmental phases. Moreover, transpiration was found to decrease at the beginning of the vegetation. In the case of the Ramrod variety, rather ambiguous results were obtained. The chlorophyll content in both pea varieties was high in the 3rd proper leaf phase and in the Rola plants it increased with increasing radiation doses in the stem extension phase

  9. Cyclobutane-type pyrimidine photodimer formation and induction of ornithine decarboxylase in human skin fibroblasts after UV irradiation

    International Nuclear Information System (INIS)

    Niggli, H.J.; Roethlisberger, R.

    1988-01-01

    Cyclobutane-type pyrimidine photodimers as well as the induction of ornithine decarboxylase (ODC) may serve as biochemical markers of the mutagenic and carcinogenic effects of ultraviolet light (UV). For this reason, it is important to compare the formation of pyrimidine dimers with the induction of ODC in human skin fibroblasts after irradiation with UVC (200-290 nm) and UVB (290-320 nm). In our studies we determined cytosine-thymine (C-T) as well as thymine-thymine dimer yields (T-T) by high-pressure liquid chromatography in cultures of neonatal normal human foreskin-derived fibroblasts after irradiation with UVC and UVB light. It was found that the yield of dimerization and the ratio of T-T/C-T decreased from the UVC to the UVB region. Time-course studies of ODC-induction in the same cells indicated that the maximal activity after UVB irradiation was retarded compared to UVC exposure. For the UV-induced ODC-levels, however, no significant difference in maximal induction could be measured after UVC and UVB irradiation at fluences where comparable yields of thymine dimerization are produced. Similar ODC-maxima were obtained with strains from children, while cells from adults showed significantly less pronounced ODC induction, indicating that ODC-response decreases with age and may therefore be used as a marker of aging

  10. Nordic Lighting?

    DEFF Research Database (Denmark)

    Munch, Anders V.

    2018-01-01

    The Danish designer Poul Henningsen wrote very elaborated theories of interior lighting from the mid-1920s on. He fought against the cold and reduced light quality of electric bulbs and tried to tame and cultivate this technology by design. He wanted a more rich light for domestic purpose...... worthwhile discussing than other design categories to interpret, whether experience of nature and climatic conditions play a role in Scandinavian Design, as repeatedly stated. This discussion contributes both to understanding of interior lighting and the historiographical critique of Scandinavian Design...... and shaped it through lamp design, colour reflections and differentiated use of several lamps in the room to make a more dim lighting, but with greater variation and softer contrasts. It was a ‘culture’ of lighting, he promoted, but he didn’t saw it as linked to the Nordic countries. His sensibility...

  11. Sistemas e condições de colheita e armazenamento na qualidade de morangos cv. Camarosa Systems and conditions of harvest and storage in strawberries cv's Camarosa quality

    Directory of Open Access Journals (Sweden)

    Marcelo Barbosa Malgarim

    2006-08-01

    Full Text Available O objetivo deste trabalho foi avaliar a qualidade de morangos 'Camarosa' submetidos a diferentes sistemas de colheita, luz UV-C, atmosfera modificada e armazenamento por diferentes períodos, visando ao aumento da vida útil e à redução de perdas após a colheita. A colheita foi realizada em dois sistemas: no sistema um, o produtor realizou a colheita sem luvas, em caixas de madeira e sem utilizar o pré-resfriamento das frutas; no sistema dois, a colheita foi realizada por pessoal treinado, com utilização de luvas desinfetadas, em caixas plásticas lavadas e desinfetadas, foi empregado o pré-resfriamento a -3ºC durante 1 hora, até a temperatura da polpa das frutas atingir 4ºC. Os tratamentos foram: T1- controle (frutas sem luz UV-C e sem filme de polietileno; T2- frutas submetidas à luz UV-C durante 6 minutos; T3- frutas acondicionadas em filme de polietileno; T4- frutas submetidas à luz UV-C e acondicionadas em filme de polietileno. O armazenamento foi realizado à temperatura de 0±0,5ºC e UR de 90-95% por períodos de 3; 6 e 9 dias, seguidos de simulação da comercialização por 3 dias, à temperatura de 8±0,5ºC e UR de 75-80%. Na colheita e após o armazenamento, avaliaram-se: perda de massa; cor; firmeza de polpa; sólidos solúveis (SS; acidez total titulável (ATT; relação SS/ATT; ácido ascórbico, e incidência de podridões. A utilização de pré-resfriamento reduziu a perda de massa e a porcentagem de podridões. A perda de massa diminuiu nas frutas tratadas com filme. A luz UV-C reduziu a porcentagem de podridões. Morangos 'Camarosa' colhidos cuidadosamente, submetidos a pré-resfriamento, com utilização de luz UV-C e filme de polietileno, mantêm a qualidade durante nove dias de armazenamento a 0ºC e 3 dias de comercialização a 8ºC.The objective of this work was to evaluate the cv. Camarosa's quality of strawberries submitted to different harvest systems, UV-C light, exposure modified atmosphere and

  12. Computer modeling and design of diagnostic workstations and radiology reading rooms

    Science.gov (United States)

    Ratib, Osman M.; Amato, Carlos L.; Balbona, Joseph A.; Boots, Kevin; Valentino, Daniel J.

    2000-05-01

    We used 3D modeling techniques to design and evaluate the ergonomics of diagnostic workstation and radiology reading room in the planning phase of building a new hospital at UCLA. Given serious space limitations, the challenge was to provide more optimal working environment for radiologists in a crowded and busy environment. A particular attention was given to flexibility, lighting condition and noise reduction in rooms shared by multiple users performing diagnostic tasks as well as regular clinical conferences. Re-engineering workspace ergonomics rely on the integration of new technologies, custom designed cabinets, indirect lighting, sound-absorbent partitioning and geometric arrangement of workstations to allow better privacy while optimizing space occupation. Innovations included adjustable flat monitors, integration of videoconferencing and voice recognition, control monitor and retractable keyboard for optimal space utilization. An overhead compartment protecting the monitors from ambient light is also used as accessory lightbox and rear-view projection screen for conferences.

  13. Indoor light and visual comfort with solar cells in glass facades

    Energy Technology Data Exchange (ETDEWEB)

    Markvart, J.; Iversen, A.; Logadottir, A.; Johnsen, K.

    2012-09-15

    This study was a part of the project 'Application of thin-film technology in Denmark' (Thi-Fi-Tech). The aim was to demonstrate how the integrating transparent thin-film PV in glazed facades in building with large glass areas influences the users' perception of the daylight in the room and the view to the outside. Panels with various patterns were constructed representing facade-integrated thin-film, both for collecting solar energy, to filter the daylight and reduce solar loads in the room. Four different dummy thin-film panels were evaluated at the daylight laboratory facility at the Danish Building Research institute in two different tests and periods, i.e. in each test there were two different panel patterns at the time in two equally arranged test rooms. After working half a day in a test room office having a large glass area where the upper and lower part was covered with an integrating transparent dummy thin-film panel, the test persons evaluated the daylight in the room and the view to the outside by answering questionnaires. Each of the four panel patterns were evaluated by 19 test persons. Besides the illuminance levels in the test rooms were measured at various strategically places and analysed. During test 1 the Pattern 4 and 6 were tested against each other as they resemble a similar structure, with the transparency of the pattern increasing towards the window in the middle. The difference between the two patterns is the geometry of the cells and the transparency. During test 2 the Pattern 3 and MicroShade pattern were tested. Pattern 3 was very similar to pattern 4 with the transparency of the pattern increasing towards the window in the middle and having opaque cells as lines with a cell dimension of 4.96 mm x 39.10 mm and a transparency of 74 %. MicroShade is a special type of solar shading constructed of transparent strips of stainless steel bands with micro-structure perforations being angled so that they shield to direct sunlight

  14. New gonioscopy system using only infrared light.

    Science.gov (United States)

    Sugimoto, Kota; Ito, Kunio; Matsunaga, Koichi; Miura, Katsuya; Esaki, Koji; Uji, Yukitaka

    2005-08-01

    To describe an infrared gonioscopy system designed to observe the anterior chamber angle under natural mydriasis in a completely darkened room. An infrared light filter was used to modify the light source of the slit-lamp microscope. A television monitor connected to a CCD monochrome camera was used to indirectly observe the angle. Use of the infrared system enabled observation of the angle under natural mydriasis in a completely darkened room. Infrared gonioscopy is a useful procedure for the observation of the angle under natural mydriasis.

  15. Influencia del tratamiento UV-C sobre carambola (Averrhoa carambola L. mínimamente procesada

    Directory of Open Access Journals (Sweden)

    María José Andrade

    2010-12-01

    Full Text Available Español:La carambola (Averroha carambola L. es una fruta tropical exótica, perteneciente a la familia de las oxalidáceas, muy cotizada en los mercados internacionales, conocida como “fruta-estrella” o “star-fruit”. Su cultivo fue introducido hace aproximadamente unos treinta años en el Ecuador. Los frutos se cosechan verdes, son altamente perecederos, se recomienda su conservación a temperaturas no menores a 5°C. Tiene una forma ovalada, alargada, con cinco aristas que al corte forman una estrella de cinco puntas por lo que se utiliza en la decoración de la cocina gourmet. El objetivo del presente estudio fue evaluar la influencia del tratamiento UV-C sobre la calidad de carambola mínimamente procesada almacenada a 5°C. Frutos recién cosechados, lavados y seleccionados, se cortaron en rodajas de 5 mm de ancho, se dividieron en dos grupos: frutos tratados (13 kJ/m2 y no tratados (controles y se almacenaron en bandejas plásticas cubiertas con film PVC durante 21 días. A los 7, 14 y 21 días se determinó la pérdida de peso, acidez, pH, sólidos solubles y se observó visualmente el avance de pardeamiento, decaimiento y firmeza al tacto. Los frutos tratados y controles presentaron un incremento en la pérdida de peso durante el almacenamiento, sin embargo, ésta fue menor en los frutos tratados. No se observaron diferencias significativas en los parámetros físico-químicos analizados a lo largo del almacenamiento. A los 14 días, los frutos control mostraron mayor pardeamiento y pérdida de firmeza que los tratados. Además, a este tiempo, los frutos control dejaron de ser consumibles dado que mostraban desarrollo de microorganismos. Los frutos tratados recién mostraron desarrollo fúngico a los 21 días de almacenamiento a 5ºC. Los resultados sugieren que el tratamiento UV-C retardó los síntomas de daño permitiendo la conservación de carambola mínimamente procesada con una buena calidad comercial por más tiempo.

  16. Treatment efficacy with ultraviolet light on the development of anthracnose (Colletotrichum gloeosporioides) and mango postharvest quality

    International Nuclear Information System (INIS)

    Mata Hidalgo, Jeremy

    2012-01-01

    The Laboratorio de Tecnologia Poscosecha and the Laboratorio de Microbiologia Agricola of the Centro de Investigaciones Agronomicas, of the Universidad de Costa Rica have initiated an mango investigation Tommy Atkins with export quality. The first trial has involved in the exposure of the fruit from the Liberia and Guanacaste area, to UV-C light at different times: 0,5,10,15,20 minutes doses corresponding to 0 kJ/m 2 -3,28 kJ/m 2 -6,57 kJ/m 2 -9,86 kJ/m 2 -13,15 kJ/m 2 . For the generation of radiation has been used a lamp 30-watts General Electric G30T8 (253,7 nm), at a distance of 15 cm above the surface of the fruit. The prochloraz fungicide commercial treatment is included (1mL/L), more hot water at 53 degrees Celsius and immersion for 3 minutes. The fruit has stored in a cold chamber at a temperature of 13 degrees Celsius ± 1 degree Celsius and a humidity of 85% for two weeks.The mango is then passed to an ambient temperature (20-22 degrees Celsius). For the second test has used mangoes of the Atenas area; the same processes are applied but with two best treatments (associated with the least damage of darkening of the skin on) observed in the first trial (5 to 10 minutes of exposure to UV-C light) in combination with wax. The evaluations and comparisons of the 2 trials were analyzed, looking at the incidence and severity of anthracnose, weight loss variables, external and internal color, Brix, acidity, firmness, incidence of damage on the shell caused by exposure to radiation and application of treatments [es

  17. Transient natural ventilation of a room with a distributed heat source

    Science.gov (United States)

    Fitzgerald, Shaun D.; Woods, Andrew W.

    We report on an experimental and theoretical study of the transient flows which develop as a naturally ventilated room adjusts from one temperature to another. We focus on a room heated from below by a uniform heat source, with both high- and low-level ventilation openings. Depending on the initial temperature of the room relative to (i) the final equilibrium temperature and (ii) the exterior temperature, three different modes of ventilation may develop. First, if the room temperature lies between the exterior and the equilibrium temperature, the interior remains well-mixed and gradually heats up to the equilibrium temperature. Secondly, if the room is initially warmer than the equilibrium temperature, then a thermal stratification develops in which the upper layer of originally hot air is displaced upwards by a lower layer of relatively cool inflowing air. At the interface, some mixing occurs owing to the effects of penetrative convection. Thirdly, if the room is initially cooler than the exterior, then on opening the vents, the original air is displaced downwards and a layer of ambient air deepens from above. As this lower layer drains, it is eventually heated to the ambient temperature, and is then able to mix into the overlying layer of external air, and the room becomes well-mixed. For each case, we present new laboratory experiments and compare these with some new quantitative models of the transient flows. We conclude by considering the implications of our work for natural ventilation of large auditoria.

  18. 9 CFR 354.226 - Lighting and ventilation.

    Science.gov (United States)

    2010-01-01

    ... Facilities § 354.226 Lighting and ventilation. There shall be ample light, either natural or artificial or both, of good quality and well distributed, and sufficient ventilation for all rooms and compartments... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Lighting and ventilation. 354.226...

  19. Design And Implementation Of Smart Living Room Wireless Control For Safety Purpose

    Directory of Open Access Journals (Sweden)

    Aeindra Myint Lwin

    2015-07-01

    Full Text Available Abstract This research presents the microcontroller controlled smart living room system using Bluetooth wireless technology from mobile phone.An android apk is created in mobile for controlling the living room system. A 16F877A microcontroller is interfaced serially to a bluetooth module transceiver. It is used for controlling fan speed control dim light control lighting ONOFF and window angle control. An arduino controller is used for keypad control door security. It is connected to DC motor control circuit and switching circuit for opening and closing of the door keypad for entering password and serial LCD for displaying the update status of the door.User can control the home appliances by using bluetooth connection from mobile phone in its range. User can adjust the dim light fan speed window angle and light bulbs from android apk. An internal EEPROM is built in 16F877A microcontroller and it stores the last requested data of the appliances. If userwants to recover the former conditions of the appliances he can recall them from android apk.

  20. The original appearance of the painted room in the Martenahuis in Franeker

    Directory of Open Access Journals (Sweden)

    Ige Verslype

    2017-09-01

    edition of 1712, whereas this is regularly the case in Frisian buildings built after 1703. As such, the painted room in the Martenahuis is one of the earliest examples of the Marot style in an upper middle-class mansion. The ambitious Suffridus Westerhuis presented himself as a modern and wealthy man of standing by having his house renovated in line with the latest architectural and interior design ideas. What’s more, the painted room he created directly mirrored Marot’s designs for Willem III (1650-1702 and his inner circle. One of the artists Westerhuis chose to do the landscape paintings in his reception room was the painter Jan van Bunnik (1654-1733, who created decorations for the palaces of the stadholder-king and for the country houses of his entourage. In seeking to align himself with the Republic’s highest echelons, Westerhuis was presenting himself as an administrator of high standing. Westerhuis took a keen interest in gardening and the study of nature, a highly appropriate pastime for a prominent figure at that time. As such, his choice of landscape hangings as wall decoration was quite apt. The contemplation of such landscapes was viewed at the time as a form of relaxation after onerous administrative duties. Architecture, paintings and client turn out to be inextricably linked in the Martenahuis room – a connection which, after having been concealed for centuries, has been brought to light by this recent research project.

  1. Room Temperature Memory for Few Photon Polarization Qubits

    Science.gov (United States)

    Kupchak, Connor; Mittiga, Thomas; Jordan, Bertus; Nazami, Mehdi; Nolleke, Christian; Figueroa, Eden

    2014-05-01

    We have developed a room temperature quantum memory device based on Electromagnetically Induced Transparency capable of reliably storing and retrieving polarization qubits on the few photon level. Our system is realized in a vapor of 87Rb atoms utilizing a Λ-type energy level scheme. We create a dual-rail storage scheme mediated by an intense control field to allow storage and retrieval of any arbitrary polarization state. Upon retrieval, we employ a filtering system to sufficiently remove the strong pump field, and subject retrieved light states to polarization tomography. To date, our system has produced signal-to-noise ratios near unity with a memory fidelity of >80 % using coherent state qubits containing four photons on average. Our results thus demonstrate the feasibility of room temperature systems for the storage of single-photon-level photonic qubits. Such room temperature systems will be attractive for future long distance quantum communication schemes.

  2. User evaluation of an innovative digital reading room.

    Science.gov (United States)

    Hugine, Akilah; Guerlain, Stephanie; Hedge, Alan

    2012-06-01

    Reading room design can have a major impact on radiologists' health, productivity, and accuracy in reading. Several factors must be taken into account in order to optimize the work environment for radiologists. Further, with the advancement in imaging technology, clinicians now have the ability to view and see digital exams without having to interact with radiologists. However, it is important to design components that encourage and enhance interactions between clinicians and radiologists to increase patient safety, and to combine physician and radiologist expertise. The present study evaluates alternative workstations in a real-world testbed space, using qualitative data (users' perspectives) to measure satisfaction with the lighting, ergonomics, furniture, collaborative spaces, and radiologist workstations. In addition, we consider the impact of the added collaboration components of the future reading room design, by utilizing user evaluation surveys to devise baseline satisfaction data regarding the innovative reading room environment.

  3. Isolation of uvh1, an Arabidopsis mutant hypersensitive to ultraviolet light and ionizing radiation

    International Nuclear Information System (INIS)

    Harlow, G.R.; Jenkins, M.E.; Pittalwala, T.S.; Mount, D.W.

    1994-01-01

    A genetic screen for mutants of Arabidopsis that are hypersensitive to UV light was developed and used to isolate a new mutant designated uvh1. UV hypersensitivity in uvh1 was due to a single recessive trait that is probably located on chromosome 3. Although isolated as hypersensitive to an acute exposure to UV-C light, uvh1 was also hypersensitive to UV-B wavelengths, which are present in sunlight that reaches the earth's surface. UV-B damage to both wild-type and uvh1 plants could be significantly reduced by subsequent exposure of UV-irradiated plants to photoreactivating light, showing that photoreactivation of UV-B damage is important for plant viability and that uvh1 plants are not defective in photoreactivation. A new assay for DNA damage, the Dral assay, was developed and used to show that exposure of wild-type and uvh1 plants to a given dose of UV light induces the same amount of damage in chloroplast and nuclear DNA. Thus, uvh1 is not defective in a UV protective mechanism. uvh1 plants were also found to be hypersensitive to ionizing radiation. These results suggest that uvh1 is defective in a repair or tolerance mechanism that normally provides plants with resistance to several types of DNA damage

  4. Isolation of uvh1, an Arabidopsis mutant hypersensitive to ultraviolet light and ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Harlow, G. R.; Jenkins, M. E.; Pittalwala, T. S.; Mount, D. W.

    1994-02-15

    A genetic screen for mutants of Arabidopsis that are hypersensitive to UV light was developed and used to isolate a new mutant designated uvh1. UV hypersensitivity in uvh1 was due to a single recessive trait that is probably located on chromosome 3. Although isolated as hypersensitive to an acute exposure to UV-C light, uvh1 was also hypersensitive to UV-B wavelengths, which are present in sunlight that reaches the earth's surface. UV-B damage to both wild-type and uvh1 plants could be significantly reduced by subsequent exposure of UV-irradiated plants to photoreactivating light, showing that photoreactivation of UV-B damage is important for plant viability and that uvh1 plants are not defective in photoreactivation. A new assay for DNA damage, the Dral assay, was developed and used to show that exposure of wild-type and uvh1 plants to a given dose of UV light induces the same amount of damage in chloroplast and nuclear DNA. Thus, uvh1 is not defective in a UV protective mechanism. uvh1 plants were also found to be hypersensitive to ionizing radiation. These results suggest that uvh1 is defective in a repair or tolerance mechanism that normally provides plants with resistance to several types of DNA damage.

  5. Influence of UV-C irradiation on expansin and pectin-methylesterase gene expression in strawberry fruit

    International Nuclear Information System (INIS)

    Pombo, M.; Dotto, M.; Martinez, G.; Civello, P.

    2005-01-01

    Full text: The exposure to UV-C delays fruit softening, one of the main factors determining fruit post harvest life. This delay in softening may be caused by changes in the activities of enzymes and proteins involved in cell wall disassembly. Expansins are cell wall proteins involved in fruit softening, while pectin-melhylesterases (PME) are cell wall enzymes related to pectin demethylation, and their activity is affected by heating, another physical treatment based on abiotic stress. We analyzed FaPME 1 gene expression in irradiated strawberry fruits and also measured PME activity after treatment. An increase in PME activity immediately after the treatment was found. The expression of FaEXP2, FaEXP4 and FaEXP5 genes was analyzed in the same fruit samples, as well as expansin protein accumulation. For these three genes we found a decrease in expression 4 h after treatment and an increase after 24 h. The decrease in gene expression after treatment correlated with a diminution of expansins. (author)

  6. Ultraviolet light photobiology of the protozoan Tetrahymena pyriformis and chemical reactivation of DNA damage

    International Nuclear Information System (INIS)

    Wheeler, J.S.

    1988-01-01

    The tunable dye laser was developed in order to perform UV-B and UV-C (254-320 nm) action spectra studies on several different organisms. Using the laser, action spectra studies have been performed for Escherichia coli, Saccharomyces, Chlamydomonas, Caenorhabditis elegans, Paramecium, and Tetrahymena pyriformis. Studies generally indicate increasing LD 50 values with increasing wavelength. Two notable findings were made: (1) The action spectra does not follow the DNA absorption spectra at 280, 290 and 295 nm; (2) The repair competent/repair defective sensitization factor does not remain constant throughout the wavelength region. In addition it was found that the repair defective strain of E. coli, Bs-1, showed an increase in survival with increasing UV irradiation, at certain dose levels. Further experiments were designed to better characterize the reactivation. Tetrahymena were exposed to UV-C and reactivated with methyl methanesulfonate (MMS) and 4-nitro quinoline oxide (4-NQO). In both cases survival was seen to increase after chemical exposure. Likewise, UV-C was found to reactivate chemical damage (MMS)

  7. Errors in radiographic recognition in the emergency room

    International Nuclear Information System (INIS)

    Britton, C.A.; Cooperstein, L.A.

    1986-01-01

    For 6 months we monitored the frequency and type of errors in radiographic recognition made by radiology residents on call in our emergency room. A relatively low error rate was observed, probably because the authors evaluated cognitive errors only, rather than include those of interpretation. The most common missed finding was a small fracture, particularly on the hands or feet. First-year residents were most likely to make an error, but, interestingly, our survey revealed a small subset of upper-level residents who made a disproportionate number of errors

  8. Room-temperature quantum noise limited spectrometry and methods of the same

    Science.gov (United States)

    Stevens, Charles G.; Tringe, Joseph W.; Cunningham, Christopher T.

    2018-05-15

    According to one embodiment, a heterodyne detection system for detecting light, includes: a first input aperture configured to receive first light from a scene input; a second input aperture configured to receive second light from a local oscillator input; a broadband local oscillator configured to provide the second light to the second input aperture; a dispersive element configured to disperse the first light and the second light; and a final condensing lens coupled to a detector. The final condensing lens is configured to concentrate incident light from a primary condensing lens onto the detector. The detector is configured to sense a frequency difference between the first light and the second light; and the final condensing lens comprises a plasmonic condensing lens. Methods for forming a plasmonic condensing lens to enable room temperature quantum noise limited spectrometry are also disclosed.

  9. Advanced upper limb prosthetic devices: implications for upper limb prosthetic rehabilitation.

    Science.gov (United States)

    Resnik, Linda; Meucci, Marissa R; Lieberman-Klinger, Shana; Fantini, Christopher; Kelty, Debra L; Disla, Roxanne; Sasson, Nicole

    2012-04-01

    The number of catastrophic injuries caused by improvised explosive devices in the Afghanistan and Iraq Wars has increased public, legislative, and research attention to upper limb amputation. The Department of Veterans Affairs (VA) has partnered with the Defense Advanced Research Projects Agency and DEKA Integrated Solutions to optimize the function of an advanced prosthetic arm system that will enable greater independence and function. In this special communication, we examine current practices in prosthetic rehabilitation including trends in adoption and use of prosthetic devices, financial considerations, and the role of rehabilitation team members in light of our experiences with a prototype advanced upper limb prosthesis during a VA study to optimize the device. We discuss key challenges in the adoption of advanced prosthetic technology and make recommendations for service provision and use of advanced upper limb prosthetics. Rates of prosthetic rejection are high among upper limb amputees. However, these rates may be reduced with sufficient training by a highly specialized, multidisciplinary team of clinicians, and a focus on patient education and empowerment throughout the rehabilitation process. There are significant challenges emerging that are unique to implementing the use of advanced upper limb prosthetic technology, and a lack of evidence to establish clinical guidelines regarding prosthetic prescription and treatment. Finally, we make recommendations for future research to aid in the identification of best practices and development of policy decisions regarding insurance coverage of prosthetic rehabilitation. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  10. Spin-on nanostructured silicon-silica film displaying room-temperature nanosecond lifetime photoluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, Y.; Hatton, B.; Miguez, H.; Coombs, N.; Fournier-Bidoz, S.; Ozin, G.A. [Materials Chemistry Research Group, Department of Chemistry, Lash Miller Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6 (Canada); Grey, J.K.; Beaulac, R.; Reber, C. [Department of Chemistry, University of Montreal, Montreal, Quebec H3C 3J7 (Canada)

    2003-04-17

    A yellow transparent mesoporous silica film has been achieved by the incorporation of silicon nanoclusters into its channels. The resulting nanocomposite - fabricated using a combination of evaporation induced self- assembly and chemical vapor deposition - emits light brightly at visible wavelengths and has nanosecond radiative lifetimes at room temperature when excited by ultraviolet light (see Figure). (Abstract Copyright [2003], Wiley Periodicals, Inc.)

  11. Control room philosophy: Principles of control room design and control room work

    International Nuclear Information System (INIS)

    Skriver, Jan; Ramberg, Jasmine; Allwin, Pernilla

    2006-01-01

    In order to provide insights for improvement of work in control rooms several factors have to be considered. Knowledge of principles including control room philosophies will guide the recommended improvements. In addition to knowledge about specific principles an advantage for an organization can be an understanding of similarities and policies used in other high risk industry. The report has been developed on the basis of a document analysis of international standards and other guiding documents. (NUREG 0711, ISO 11064, ISO 6385, IEC 60964). In addition to the document analysis which has strived to compare the documents to see similarities in important principals, experience from working with control room design, modifications and evaluations in other high risk industries has pervaded the report. Important principles have been identified which are recommended to be included in a control room philosophy. Many of these are similar to the principles identified in the international standards. An additional principal which is regarded as important is the utilization of Key Performance Indicators (KPI) which can be used as a measure to target preventative means. Further more it is critical that the control room philosophy is easy to access and comprehend for all users. One of the challenges that remain after having developed a control room philosophy is how to utilize it in the daily work situation. It is vital that the document remains as a living document, guiding the continual improvement of the control room in the various life cycle stages

  12. Green Lighting. Energy-efficient integrated lighting systems - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Linhart, F.; Scartezzini, J.-L.

    2009-10-15

    The objective of the Green Lighting project was to develop a High Performance Integrated Lighting System, based on advanced technologies for day- and electric lighting, achieving a Lighting Power Density (LPD) that does not exceed 3 W/m{sup 2}. The project has revealed that Anidolic Daylighting Systems (ADS) are an ideal basis for High Performance Integrated Lighting Systems. Not only are they able to provide adequate illumination (i.e. sufficiently high illuminance) in office rooms during large fractions of normal office hours, under various sky conditions and over the entire year, but they are also highly appreciated by office occupants at the condition that glare control mechanisms are available. Complementary electric lighting is, however, still necessary to back up the ADS at times when there is insufficient daylight flux available. It was shown during this project, that the most interesting trade-offs between energy-efficiency and visual comfort are obtained by using a combination of ceiling-mounted directly emitting luminaires with very high optical efficiencies for ambient lighting and portable desk lamps for temporary task lighting. The most appropriate lamps for the ceiling-mounted luminaires are currently highly efficient fluorescent tubes, but white LED tubes can be considered a realistic option for the future. The most suitable light sources for desk lamps for temporary task lighting are Compact Fluorescent Lamps (CFLs) and white LED light bulbs. Based on the above-mentioned technologies, a High Performance Integrated Lighting System with a very low LPD has been developed over the last three years. The system has been set up in an office room of the LESO solar experimental building located on the EPFL campus; it has been tested intensively during a Post-Occupancy Evaluation (POE) study involving twenty human subjects. This study has revealed that the subjects' performance and subjective visual comfort was improved by the new system, compared to

  13. Comparison of two whole-room ultraviolet irradiation systems for enhanced disinfection of contaminated hospital patient rooms.

    Science.gov (United States)

    Ali, S; Yui, S; Muzslay, M; Wilson, A P R

    2017-10-01

    Ultraviolet (UV) light decontamination systems are being used increasingly to supplement terminal disinfection of patient rooms. However, efficacy may not be consistent in the presence of soil, especially against Clostridium difficile spores. To demonstrate in-use efficacy of two whole-room UV decontamination systems against three hospital pathogens with and without soil. For each system, six patient rooms were decontaminated with UV irradiation (enhanced disinfection) following manual terminal cleaning. Total aerobic colony counts of surface contamination were determined by spot-sampling 15 environmental sites before and after terminal disinfection and after UV irradiation. Efficacy against biological indicator coupons (stainless-steel discs) was performed for each system using test bacteria (10 6  cfu EMRSA-15 variant A, carbapenemase-producing Klebsiella pneumoniae) or spores (10 5  cfu C. difficile 027), incorporating low soiling [0.03% bovine serum albumin (BSA)], heavy soiling (10% BSA) or synthetic faeces (C. difficile only) placed at five locations in the room. UV disinfection eliminated contamination after terminal cleaning in 8/14 (57%) and 11/14 (79%) sites. Both systems demonstrated 4-5 log 10 reductions in meticillin-resistant Staphylococcus aureus and K. pneumoniae at low soiling. Lower and more variable log 10 reductions were achieved when heavy soiling was present. Between 0.1 and 4.8 log 10 reductions in C. difficile spores were achieved with low but not heavy soil challenge. Terminal disinfection should be performed on all surfaces prior to UV decontamination. In-house validation studies should be considered to ensure optimal positioning in each room layout and sufficient cycle duration to eliminate target pathogens. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  14. Photodynamic effect of light-emitting diode light on cell growth ...

    Indian Academy of Sciences (India)

    Madhu urs

    Photodynamic effect of LED light on cell growth inhibition induced by methylene blue. 231. J. Biosci. ... high costs make PDT inaccessible for many institutions .... After 48 h at room temperature, 20 mature ... decrease in turbidity of the medium and the increase in %T ..... Mechanistic study of the photodynamic inactivation of.

  15. Ultraviolet radiation for the sterilization of contact lenses

    International Nuclear Information System (INIS)

    Gritz, D.C.; Lee, T.Y.; McDonnell, P.J.; Shih, K.; Baron, N.

    1990-01-01

    Two sources of ultraviolet (UV) radiation with peak wavelengths in the UV-C or UV-B ranges were compared for their ability to sterilize contact lenses infected with Pseudomonas aeruginosa, Streptococcus pneumoniae, Acanthamoeba castellani, Candida albicans, and Aspergillus niger. Also examined was the effect of prolonged UV light exposure on soft and rigid gas permeable (RGP) contact lenses. The UV-C lamp (253.7 nm, 250 mW/cm2 at 1 cm) was germicidal for all organisms within 20 minutes but caused destruction of the soft lens polymers within 6 hours of cumulative exposure. UV-C caused damage to RGP lenses in less than 100 hours. The UV-B lamp (290-310 nm, 500 mW/cm2 at 1 cm) was germicidal for all organisms tested (except Aspergillus) with a 180-minute exposure and caused less severe changes in the soft lens polymers than did the UV-C lamp, although cumulative exposure of 300 hours did substantially weaken the soft lens material. RGP materials were minimally affected by exposure to 300 hours of UV-B. Ultraviolet light is an effective germicidal agent but is injurious to soft lens polymers; its possible utility in the sterilization of RGP lenses and lens cases deserves further study

  16. Measuring Human Performance in Simulated Nuclear Power Plant Control Rooms Using Eye Tracking

    Energy Technology Data Exchange (ETDEWEB)

    Kovesdi, Casey Robert [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Brandon Charles [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bower, Gordon Ross [Idaho National Lab. (INL), Idaho Falls, ID (United States); Spielman, Zachary Alexander [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hill, Rachael Ann [Idaho National Lab. (INL), Idaho Falls, ID (United States); LeBlanc, Katya Lee [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-11-01

    Control room modernization will be an important part of life extension for the existing light water reactor fleet. As part of modernization efforts, personnel will need to gain a full understanding of how control room technologies affect performance of human operators. Recent advances in technology enables the use of eye tracking technology to continuously measure an operator’s eye movement, which correlates with a variety of human performance constructs such as situation awareness and workload. This report describes eye tracking metrics in the context of how they will be used in nuclear power plant control room simulator studies.

  17. Measuring Human Performance in Simulated Nuclear Power Plant Control Rooms Using Eye Tracking

    International Nuclear Information System (INIS)

    Kovesdi, Casey Robert; Rice, Brandon Charles; Bower, Gordon Ross; Spielman, Zachary Alexander; Hill, Rachael Ann; LeBlanc, Katya Lee

    2015-01-01

    Control room modernization will be an important part of life extension for the existing light water reactor fleet. As part of modernization efforts, personnel will need to gain a full understanding of how control room technologies affect performance of human operators. Recent advances in technology enables the use of eye tracking technology to continuously measure an operator's eye movement, which correlates with a variety of human performance constructs such as situation awareness and workload. This report describes eye tracking metrics in the context of how they will be used in nuclear power plant control room simulator studies.

  18. UV-C decontamination of hand-held tablet devices in the healthcare environment using the Codonics D6000™ disinfection system.

    Science.gov (United States)

    Muzslay, M; Yui, S; Ali, S; Wilson, A P R

    2018-04-09

    Mobile phones and tablet computers may be contaminated with microorganisms and become a potential reservoir for cross-transmission of pathogens between healthcare workers and patients. There is no generally accepted guidance how to reduce contamination on mobile devices in healthcare settings. Our aim was to determine the efficacy of the Codonics D6000™ UV-C disinfection device. Daily disinfection reduced contamination on screens and on protective cases (test) significantly, but not all cases (control) could be decontaminated. The median aerobic colony count on the control and the test cases was 52 (IQR 33-89) cfu/25cm 2 and 22 (IQR 10.5-41) cfu/25cm 2 respectively before disinfection. Copyright © 2018. Published by Elsevier Ltd.

  19. Calculus light

    CERN Document Server

    Friedman, Menahem

    2011-01-01

    Another Calculus book? As long as students find calculus scary, the failure rate in mathematics is higher than in all other subjects, and as long as most people mistakenly believe that only geniuses can learn and understand mathematics, there will always be room for a new book of Calculus. We call it Calculus Light. This book is designed for a one semester course in ""light"" calculus -- mostly single variable, meant to be used by undergraduate students without a wide mathematical background and who do not major in mathematics but study subjects such as engineering, biology or management infor

  20. Evaluation of UV-C mutagenized Scheffersomyces stipitis strains for ethanol production.

    Science.gov (United States)

    Geiger, Melanie; Gibbons, Jaimie; West, Thomas; Hughes, Stephen R; Gibbons, William

    2012-12-01

    We evaluated fermentation capabilities of five strains of Scheffersomyces stipitis (WT-2-1, WT-1-11, 14-2-6, 22-1-1, and 22-1-12) that had been produced by UV-C mutagenesis and selection for improved xylose fermentation to ethanol using an integrated automated robotic work cell. They were incubated under both facultative and anaerobic conditions to evaluate ethanol production on glucose, xylose, cellobiose, and a combination of all three sugars. The medium contained 50 g/L total sugar and 5 g/L yeast extract. The strains performed significantly better under facultative compared with anaerobic conditions. As expected, glucose was the most readily fermented sugar with ~100% fermentation efficiency (FE) under facultative conditions but only 5% to 16% FE anaerobically. Xylose utilization was 20% to 40% FE under facultative conditions but 9% to 25% FE anaerobically. Cellobiose was the least fermented sugar, at 18% to 27% FE facultatively and 8% to 11% anaerobically. Similar trends occurred in the sugar mixture. Under facultative conditions, strain 22-1-12 produced 19.6 g/L ethanol on glucose, but strain 14-2-6 performed best on xylose (4.5 g/L ethanol) and the sugar combination (8.0 g/L ethanol). Ethanol titers from glucose under anaerobic conditions were again highest with strain 22-1-12, but none of the strains produced ethanol from xylose. Future trials will evaluate nutrient addition to boost microaerophilic xylose fermentation.

  1. Effects of coloured lighting on the perception of interior spaces.

    Science.gov (United States)

    Odabaşioğlu, Seden; Olguntürk, Nіlgün

    2015-02-01

    Use of coloured lighting in interior spaces has become prevalent in recent years. Considerable importance is ascribed to coloured lighting in interior and lighting design. The effects of colour on the perception of interior spaces have been studied as surface colour; but here, the effects of three different types of chromatic light were investigated. The lighting differed in colour (red, green and white) and perceptions of interior space were assessed. 97 participants (59 women, 38 men; M age = 21.4 yr.) evaluated the experiment room on a questionnaire assessing eight evaluative factors: Pleasantness, Arousal, Aesthetics, Usefulness, Comfort, Spaciousness, Colour, and Lighting quality. Perceptions of the room differed by colour of lighting for some of the evaluative factors, but there was no sex difference in perceptions. Interior spaces may be perceived as equally pleasant under white, green and red lighting. Under white lighting a space is perceived as more useful, spacious, clear, and luminous. Green lighting would make the same effect. Green and white lighting were perceived equally comfortable in an interior space. Chromatic coloured lighting was perceived to be more aesthetic than white lighting. The results support previous findings for some evaluative factors, but differed for others.

  2. Multichannel active control of random noise in a small reverberant room

    DEFF Research Database (Denmark)

    Laugesen, Søren; Elliott, Stephen J.

    1993-01-01

    An algorithm for multichannel adaptive IIR (infinite impulse response) filtering is presented and applied to the active control of broadband random noise in a small reverberant room. Assuming complete knowledge of the primary noise, the theoretically optimal reductions of acoustic energy are init...... with the primary noise field generated by a panel excited by a loudspeaker in an adjoining room. These results show that far better performances are provided by IIR and FIR filters when the primary source has a lightly damped dynamic behavior which the active controller must model...

  3. Benefits of Advanced Control Room Technologies: Phase One Upgrades to the HSSL, Research Plan, and Performance Measures

    Energy Technology Data Exchange (ETDEWEB)

    Le Blanc, Katya [Idaho National Lab. (INL), Idaho Falls, ID (United States); Joe, Jeffrey [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Brandon [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ulrich, Thomas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Boring, Ronald [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-05-01

    Control Room modernization is an important part of life extension for the existing light water reactor fleet. None of the 99 currently operating commercial nuclear power plants in the U.S. has completed a full-scale control room modernization to date. A full-scale modernization might, for example, entail replacement of all analog panels with digital workstations. Such modernizations have been undertaken successfully in upgrades in Europe and Asia, but the U.S. has yet to undertake a control room upgrade of this magnitude. Instead, nuclear power plant main control rooms for the existing commercial reactor fleet remain significantly analog, with only limited digital modernizations. Previous research under the U.S. Department of Energy’s Light Water Reactor Sustainability Program has helped establish a systematic process for control room upgrades that support the transition to a hybrid control room. While the guidance developed to date helps streamline the process of modernization and reduce costs and uncertainty associated with introducing digital control technologies into an existing control room, these upgrades do not achieve the full potential of newer technologies that might otherwise enhance plant and operator performance. The aim of the control room benefits research is to identify previously overlooked benefits of modernization, identify candidate technologies that may facilitate such benefits, and demonstrate these technologies through human factors research. This report describes the initial upgrades to the HSSL and outlines the methodology for a pilot test of the HSSL configuration.

  4. Plant Leaf Imaging using Time of Flight Camera under Sunlight, Shadow and Room Conditions

    DEFF Research Database (Denmark)

    Kazmi, Wajahat; Foix, Sergi; Alenya, Guillem

    2012-01-01

    In this article, we analyze the effects of ambient light on Time of Flight (ToF) depth imaging for a plant's leaf in sunlight, shadow and room conditions. ToF imaging is sensitive to ambient light and we try to find the best possible integration times (IT) for each condition. This is important in...

  5. Room-temperature synthesis of Zn(0.80)Cd(0.20)S solid solution with a high visible-light photocatalytic activity for hydrogen evolution.

    Science.gov (United States)

    Wang, Dong-Hong; Wang, Lei; Xu, An-Wu

    2012-03-21

    Visible light photocatalytic H(2) production from water splitting is of great significance for its potential applications in converting solar energy into chemical energy. In this study, a series of Zn(1-x)Cd(x)S solid solutions with a nanoporous structure were successfully synthesized via a facile template-free method at room temperature. The obtained solid solutions were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS) and N(2) adsorption-desorption analysis. The solid solutions show efficient photocatalytic activity for H(2) evolution from aqueous solutions containing sacrificial reagents S(2-) and SO(3)(2-) under visible-light irradiation without a Pt cocatalyst, and loading of the Pt cocatalyst further improves the visible-light photocatalytic activity. The optimal photocatalyst with x = 0.20 prepared at pH = 7.3 displays the highest activity for H(2) evolution. The bare and 0.25 wt% Pt loaded Zn(0.80)Cd(0.20)S nanoparticles exhibit a high H(2) evolution rate of 193 μmol h(-1) and 458 μmol h(-1) under visible-light irradiation (λ ≥ 420 nm), respectively. In addition, the bare and 0.25 wt% Pt loaded Zn(0.80)Cd(0.20)S catalysts show a high H(2) evolution rate of 252 and 640 μmol h(-1) under simulated solar light irradiation, respectively. Moreover, the Zn(0.80)Cd(0.20)S catalyst displays a high photocatalytic stability for H(2) evolution under long-term light irradiation. The incorporation of Cd in the solid solution leads to the visible light absorption, and the high content of Zn in the solid solution results in a relatively negative conduction band, a modulated band gap and a rather wide valence bandwidth, which are responsible for the excellent photocatalytic performance of H(2) production and for the high photostability

  6. White light Sagnac interferometer—a common (path) tale of light

    International Nuclear Information System (INIS)

    Schwartz, Eyal

    2017-01-01

    White or polychromatic light sources are vastly abundant in nature and lie in our most basic understanding of the theory of light, beginning from stars like our Sun and extending to every common household light bulb or street lamp. In this paper, I present concepts of white light interferometery using a common-path Sagnac interferometer, manifested in a straightforward laboratory experiment. I further show the use of this as a Fourier transform spectrometer while presenting a basic overview of the theoretical concepts and spectrum of different light sources obtained experimentally. This work, both experimentally and analytically, is suitable for upper-level undergraduate physics or engineering courses where electromagnetic theory and optics are discussed. The experiment and theory presents important deep concepts and aspects in modern optics and physics that every science student should acquire. (paper)

  7. White light Sagnac interferometer—a common (path) tale of light

    Science.gov (United States)

    Schwartz, Eyal

    2017-11-01

    White or polychromatic light sources are vastly abundant in nature and lie in our most basic understanding of the theory of light, beginning from stars like our Sun and extending to every common household light bulb or street lamp. In this paper, I present concepts of white light interferometery using a common-path Sagnac interferometer, manifested in a straightforward laboratory experiment. I further show the use of this as a Fourier transform spectrometer while presenting a basic overview of the theoretical concepts and spectrum of different light sources obtained experimentally. This work, both experimentally and analytically, is suitable for upper-level undergraduate physics or engineering courses where electromagnetic theory and optics are discussed. The experiment and theory presents important deep concepts and aspects in modern optics and physics that every science student should acquire.

  8. Room Acoustics

    Science.gov (United States)

    Kuttruff, Heinrich; Mommertz, Eckard

    The traditional task of room acoustics is to create or formulate conditions which ensure the best possible propagation of sound in a room from a sound source to a listener. Thus, objects of room acoustics are in particular assembly halls of all kinds, such as auditoria and lecture halls, conference rooms, theaters, concert halls or churches. Already at this point, it has to be pointed out that these conditions essentially depend on the question if speech or music should be transmitted; in the first case, the criterion for transmission quality is good speech intelligibility, in the other case, however, the success of room-acoustical efforts depends on other factors that cannot be quantified that easily, not least it also depends on the hearing habits of the listeners. In any case, absolutely "good acoustics" of a room do not exist.

  9. A Designed Room Temperature Multilayered Magnetic Semiconductor

    Science.gov (United States)

    Bouma, Dinah Simone; Charilaou, Michalis; Bordel, Catherine; Duchin, Ryan; Barriga, Alexander; Farmer, Adam; Hellman, Frances; Materials Science Division, Lawrence Berkeley National Lab Team

    2015-03-01

    A room temperature magnetic semiconductor has been designed and fabricated by using an epitaxial antiferromagnet (NiO) grown in the (111) orientation, which gives surface uncompensated magnetism for an odd number of planes, layered with the lightly doped semiconductor Al-doped ZnO (AZO). Magnetization and Hall effect measurements of multilayers of NiO and AZO are presented for varying thickness of each. The magnetic properties vary as a function of the number of Ni planes in each NiO layer; an odd number of Ni planes yields on each NiO layer an uncompensated moment which is RKKY-coupled to the moments on adjacent NiO layers via the carriers in the AZO. This RKKY coupling oscillates with the AZO layer thickness, and it disappears entirely in samples where the AZO is replaced with undoped ZnO. The anomalous Hall effect data indicate that the carriers in the AZO are spin-polarized according to the direction of the applied field at both low temperature and room temperature. NiO/AZO multilayers are therefore a promising candidate for spintronic applications demanding a room-temperature semiconductor.

  10. The Design and Comparison of Central and Distributed Light Sensored Smart LED Lighting Systems

    Directory of Open Access Journals (Sweden)

    Mehmet Ali Özçelik

    2018-01-01

    Full Text Available There is a lack of published peer-reviewed research comparing the efficiencies of distributed versus central sensor-controlled LED lighting systems. This research proposes improving the smart illumination of a room with external fenestration using central and distributed light sensors. The optical and electrical measurements of the daylight have been made in the case where the light was not distributed evenly and not sufficient. Test results show that the proposed distributed light sensor illumination system has increased the efficiency by 28% when compared to the proposed central system. It has also been shown that the two tested systems are more cost-effective than common smart illumination systems.

  11. Uso combinado de radiación UV-C y biorecubrimiento de quitosán con aceites esenciales para el control de hongos en papaya Maradol

    Directory of Open Access Journals (Sweden)

    Alfredo Vázquez-Ovando

    2018-05-01

    Full Text Available Resumen La antracnosis y pudrición blanda en frutos de papaya provocan deterioro de la calidad, así como grandes pérdidas durante el manejo postcosecha. El uso de estrategias individuales para el control de enfermedades resulta poco eficiente. Por lo anterior, en el presente estudio se evaluó el efecto sinérgico de varias estrategias de control sobre la incidencia de enfermedad causada por la inoculación de esporas de los hongos Colletotrichum gloeosporioides (Penz. y Rhizopus stolonifer (Ehrenb. en papaya var. Maradol. Se evaluaron tratamientos resultantes de la combinación del uso de biorecubrimientos compuestos elaborados con quitosán (15 g L-1 adicionadas con aceites esenciales (AE de clavo, tomillo y/o lima (5 ó 10 mL L-1 de cada AE y tres dosis de irradiación UV-C (0.97 kJ·m-2, 2 kJ·m-2 y 2.88 kJ·m-2, aplicados a las 12, 24 y 48 h post-inoculación de esporas de los fitopatógenos. El tratamiento donde se combinó el biorecubrimiento adicionado con 10 mL L-1 de AE de clavo y 10 mL L-1 de AE de tomillo y una dosis de irradiación UV-C de 2.88 kJ m-2 (B1T92 aplicado a las 24 h post-inoculación de esporas, logró mantener la incidencia de enfermedad (para ambos hongos evaluados a valores menores de 25% durante nueve días de almacenamiento a temperatura de 28 ± 3 °C y 80% de HR. Este mismo tratamiento redujo la velocidad específica de la enfermedad, con valores de 0.549 y 0.029 d-1 para C. gloeosporioidesy R. stolonifer, respectivamente. Otros tratamientos (B2T62, B1T34, B1T34, B1T94 presentaron actividad antifúngica (valores promedio de incidencia de 35% durante todo el almacenamiento para R. stolonifer. Los resultados de este trabajo demuestran que el efecto sinérgico del uso de biorecubrimientos de quitosán con aceites esenciales y energía UV-C controla el desarrollo de hongos causantes de antracnosis y pudrición blanda en frutos de papaya Maradol.

  12. Result of comparative experiment on environmental comfort in room using hot heat environment testing unit. Onnetsu kankyo shiken unit ni yoru shitsunai kankyo no kaitekisa no hikaku jikken kekka ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, T; Kawashima, K [The Hokkaido Electric Power Co. Inc., Sapporo (Japan)

    1991-11-20

    Measurements were carried out on three buildings having different heat insulation, airtightness and heat capacity for testing the hot heast enviroments (having a room size of about 4.6 m{times}3.7m{times}2.3 m) as to the temperature differences between the upper and lower parts of the room and the MRT (mean radiation temperature, representing the temperature of radiation from the wall face). These are compared according to types of heating appliance. The result is summarize as follows: The temperature difference in the upper and lower parts is affected largely by the airtightness of the building, the difference being capable of getting reduced by rasing the airtightness even in a buildings low in heat insulation. In a building with low airtightness, type of heating appliance and its installation location affect the temperature difference. The MRT is determined determined nearly completely by the heat insulation of the wall face in a room, but it tends to be affected easily by the specification and area of windows. A floor heating system increases the MRT and generates very little difference in temperatures in the upper and lower parts of the room. A comparison using a PMV (one of the indexes for enviromental comfort in a room) was also conducted. 12 figs., 7tabs.

  13. Terahertz light-emitting graphene-channel transistor toward single-mode lasing

    Science.gov (United States)

    Yadav, Deepika; Tamamushi, Gen; Watanabe, Takayuki; Mitsushio, Junki; Tobah, Youssef; Sugawara, Kenta; Dubinov, Alexander A.; Satou, Akira; Ryzhii, Maxim; Ryzhii, Victor; Otsuji, Taiichi

    2018-03-01

    A distributed feedback dual-gate graphene-channel field-effect transistor (DFB-DG-GFET) was fabricated as a current-injection terahertz (THz) light-emitting laser transistor. We observed a broadband emission in a 1-7.6-THz range with a maximum radiation power of 10 μW as well as a single-mode emission at 5.2 THz with a radiation power of 0.1 μW both at 100 K when the carrier injection stays between the lower cutoff and upper cutoff threshold levels. The device also exhibited peculiar nonlinear threshold-like behavior with respect to the current-injection level. The LED-like broadband emission is interpreted as an amplified spontaneous THz emission being transcended to a single-mode lasing. Design constraints on waveguide structures for better THz photon field confinement with higher gain overlapping as well as DFB cavity structures with higher Q factors are also addressed towards intense, single-mode continuous wave THz lasing at room temperature.

  14. Using a Research Simulator for Validating Control Room Modernization Concepts

    International Nuclear Information System (INIS)

    Boring, Ronald L.; Agarwal, Vivek; Persensky, Julius J.; Joe, Jeffrey C.

    2012-01-01

    The Light Water Reactor Sustainability Program is a research, development, and deployment program sponsored by the United States Department of Energy. The program is operated in close collaboration with industry research and development programs to provide the technical foundations for licensing and managing the long-term, safe, and economical operation of nuclear power plants that are currently in operation. Advanced instrumentation and control (I and C) technologies are needed to support the continued safe and reliable production of power from nuclear energy systems during sustained periods of operation up to and beyond their expected licensed lifetime. This requires that new capabilities to achieve process control be developed and eventually implemented in existing nuclear control rooms. It also requires that approaches be developed and proven to achieve sustainability of I and C systems throughout the period of extended operation. Idaho National Laboratory (INL) is working closely with nuclear utilities to develop technologies and solutions to help ensure the safe life extension of current reactors. One of the main areas of focus is control room modernization. Current analog control rooms are growing obsolete, and it is difficult for utilities to maintain them. Using its reconfigurable control room simulator adapted from a training simulator, INL serves as a neutral test bed for implementing new control room system technologies and assisting in control room modernization efforts across. (author)

  15. Using a Research Simulator for Validating Control Room Modernization Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Ronald L. Boring; Vivek Agarwal; Julius J. Persensky; Jeffrey C. Joe

    2012-05-01

    The Light Water Reactor Sustainability Program is a research, development, and deployment program sponsored by the United States Department of Energy. The program is operated in close collaboration with industry research and development programs to provide the technical foundations for licensing and managing the long-term, safe, and economical operation of nuclear power plants that are currently in operation. Advanced instrumentation and control (I&C) technologies are needed to support the continued safe and reliable production of power from nuclear energy systems during sustained periods of operation up to and beyond their expected licensed lifetime. This requires that new capabilities to achieve process control be developed and eventually implemented in existing nuclear control rooms. It also requires that approaches be developed and proven to achieve sustainability of I&C systems throughout the period of extended operation. Idaho National Laboratory (INL) is working closely with nuclear utilities to develop technologies and solutions to help ensure the safe life extension of current reactors. One of the main areas of focus is control room modernization. Current analog control rooms are growing obsolete, and it is difficult for utilities to maintain them. Using its reconfigurable control room simulator adapted from a training simulator, INL serves as a neutral test bed for implementing new control room system technologies and assisting in control room modernization efforts across.

  16. Synthesis and thermoluminescence of LaAlO3:Pr3+ to UVC radiation dosimetry

    International Nuclear Information System (INIS)

    Morales-Hernández, A.; Zarate-Medina, J.; Contreras-García, M.E.; Azorín-Nieto, J.; Rivera-Montalvo, T.

    2016-01-01

    Thermoluminescent (TL) response of trivalent praseodymium ion doped lanthanum aluminate (LaAlO 3 :Pr 3+ ) obtained by Pechini method and Spray Dryer was studied. TL response of LaAlO 3 :Pr 3+ powders submitted at 1600 °C exhibited one peak centered at 157 °C. Sensitivity of LaAlO 3 :Pr 3+ was improved in around 90 times compared with undoped LaAlO 3 . TL response as a function of wavelength showed a maximum in 230 nm. Dosimetric characteristics of LaAlO 3 :Pr 3+ under UVR radiation effects were analyzed. Evaluation of activation energy was obtained by Glow Fit v.1.3 software. Experimental results about thermoluminescent characteristics of LaAlO 3 :Pr 3+ suggest as good candidate to be employed as a complementary thermoluminescent device with other TL phosphors as aluminum oxide - Highlights: • High sensitivity of new phosphor to UVC dosimetry was is studied. • Thermoluminescence response of LaAlO 3 :Pr 3+ is presented. • LaAlO 3 :Pr 3+ is suggested as UVCR dosimeter. • TL response of LaAlO 3 :Pr 3+ has dependence on sintering temperature.

  17. Site and strand specificity of UVB mutagenesis in the SUP4-o gene of yeast

    International Nuclear Information System (INIS)

    Armstrong, J.D.; Kunz, B.A.

    1990-01-01

    DNA sequencing was used to characterize 208 mutations induced in the SUP4-o tRNA gene of the yeast Saccharomyces cerevisiae by UVB (285-320 nm) radiation. The results were compared to those for an analysis of 211 SUP4-o mutations induced by 254-nm UVC light. In each case, greater than 90% of the mutations were single base-pair changes but G.C----A.T transitions predominated and accounted for more of the mutations induced by UVB than UVC. Double substitutions, single base-pair deletions, and more complex events were also recovered. However, UVB induced 3-fold more tandem substitutions than UVC and nontandem double events were detected only after irradiation with UVC. Virtually all induced substitutions occurred at sites where the pyrimidine of the base pair was part of a dipyrimidine sequence. Although the site specificities were consistent with roles for cyclobutane dimers and pyrimidine-pyrimidone(6-4) lesions in mutation induction, preliminary photoreactivation data implicated cyclobutane dimers as the major form of premutational DNA damage for both agents. Intriguingly, there was a preference for both UVB- and UVC-induced mutations to occur at sites where the dipyrimidine was on the transcribed strand

  18. The influence of bubble populations generated under windy conditions on the blue-green light transmission in the upper ocean: An exploratory approach

    Science.gov (United States)

    Wang, Chengan; Tan, Jianyu; Lai, Qingzhi

    2016-12-01

    The “blue-green window” in the ocean plays an important role in functions such as communication between vessels, underwater target identification, and remote sensing. In this study, the transmission process of blue-green light in the upper ocean is analyzed numerically using the Monte Carlo method. First, the effect of total number of photons on the numerical results is evaluated, and the most favorable number is chosen to ensure accuracy without excessive costs for calculation. Then, the physical and mathematical models are constructed. The rough sea surface is generated under windy conditions and the transmission signals are measured in the far field. Therefore, it can be conceptualized as a 1D slab with a rough boundary surface. Under windy conditions, these bubbles form layers that are horizontally homogeneous and decay exponentially with depth under the influence of gravity. The effects of bubble populations on the process of blue-green light transmission at different wind speeds, wavelengths, angle of incidence and chlorophyll-a concentrations are studied for both air-incident and water-incident cases. The results of this study indicate that the transmission process of blue-green light is significantly influenced by bubbles under high wind-speed conditions.

  19. Strong-coupling of WSe2 in ultra-compact plasmonic nanocavities at room temperature.

    Science.gov (United States)

    Kleemann, Marie-Elena; Chikkaraddy, Rohit; Alexeev, Evgeny M; Kos, Dean; Carnegie, Cloudy; Deacon, Will; de Pury, Alex Casalis; Große, Christoph; de Nijs, Bart; Mertens, Jan; Tartakovskii, Alexander I; Baumberg, Jeremy J

    2017-11-03

    Strong coupling of monolayer metal dichalcogenide semiconductors with light offers encouraging prospects for realistic exciton devices at room temperature. However, the nature of this coupling depends extremely sensitively on the optical confinement and the orientation of electronic dipoles and fields. Here, we show how plasmon strong coupling can be achieved in compact, robust, and easily assembled gold nano-gap resonators at room temperature. We prove that strong-coupling is impossible with monolayers due to the large exciton coherence size, but resolve clear anti-crossings for greater than 7 layer devices with Rabi splittings exceeding 135 meV. We show that such structures improve on prospects for nonlinear exciton functionalities by at least 10 4 , while retaining quantum efficiencies above 50%, and demonstrate evidence for superlinear light emission.

  20. Affective ambiences created with lighting for older people

    NARCIS (Netherlands)

    Kuijsters, A.; Redi, J.; Ruyter, B.E.R. de; Seuntiens, P.; Heynderickx, I.

    2015-01-01

    Current lighting technologies provide huge flexibility in creating ambiences that may be adapted to the needs of an occupant in a room. These ambiences not only satisfy visual needs, but may also improve people’s well-being. This paper describes one possible application of adaptable light ambiences,

  1. Advanced oxidation of a reactive dyebath effluent: comparison of O3, H2O2/UV-C and TiO2/UV-A processes.

    Science.gov (United States)

    Alaton, Idil Arslan; Balcioglu, Isil Akmehmet; Bahnemann, Detlef W

    2002-03-01

    In the present study the treatment efficiency of different AOPs (O3/OH- H2O2/UV-C and TiO2/UV-A) were compared for the oxidation of simulated reactive dyebath effluent containing a mixture of monochlorotriazine type reactive dyes and various dye auxiliary chemicals at typical concentrations encountered in exhausted reactive dyebath liquors. A525 (color), UV280 (aromaticity) and TOC removal rates were assessed to screen the most appropriate oxidative process in terms of reactive dyebath effluent treatment. Special emphasis was laid on the effect of reaction pH and applied oxidant (O3, H2O2) dose on the observed reaction kinetics. It was established that the investigated AOPs were negatively affected by the Na2CO3 content (= 867 mg/L) which is always present at high concentrations in dychouse effluents since it is applied as a pH buffer and dye fixation agent during the reactive dyeing process. The ozonation reaction exhibited almost instantaneous decolorization kinetics and a reasonable TOC reduction rate. It appeared to be stable under the investigated advanced oxidation conditions and outranked the other studied AOPs based on the above mentioned criteria. Besides, the electrical energy requirements based on the EE/O parameter (the electrical energy required per order of pollutant removal in 1 m3 wastewater) was calculated for the homogenous AOPs in terms of decolorization kinetics. In view of the electrical energy efficiency, ozonation and H2O2/UV-C oxidation at the selected treatment conditions appear to be promising candidates for full-scale dyehouse effluent decolorization.

  2. Hole-exciton interaction induced high field decay of magneto-electroluminescence in Alq3-based organic light-emitting diodes at room temperature

    Science.gov (United States)

    Zhang, Tingting; Holford, D. F.; Gu, Hang; Kreouzis, T.; Zhang, Sijie; Gillin, W. P.

    2016-01-01

    The magnetic field effects on the electroluminescence of aluminium tris-(8-hydroxyqinoline) (Alq3) based organic light emitting diodes have been investigated by varying the electron/hole ratio in the emissive layer. Experimental results reveal that a negative high field effect in the magneto-electroluminescence (MEL) can be found in devices with very low triplet exciton concentration at room temperature. This suggests triplet-triplet annihilation cannot be used to explain the negative high field MEL in the Alq3 system. Our results suggest that hole-exciton interaction may be the origin of the negative high field MEL and also, in parallel with this interaction, there is also the more common positive high field process occurring which has been tentatively attributed to electron-exciton interactions. The competition between these different processes decides the final shape of the MEL at high fields.

  3. A 13 kA current lead, measuring 1.5 m in length. The lower part consists of a high-temperature superconductor (Bi-2223), operating at between 50 K and 4.5 K, while the heat-exchanger upper part allows the current to be brought from room temperature to 50 K.

    CERN Multimedia

    2004-01-01

    A 13 kA current lead, measuring 1.5 m in length. The lower part consists of a high-temperature superconductor (Bi-2223), operating at between 50 K and 4.5 K, while the heat-exchanger upper part allows the current to be brought from room temperature to 50 K.

  4. One hundred prisoners and a light bulb

    CERN Document Server

    van Ditmarsch, Hans

    2015-01-01

    A group of 100 prisoners, all together in the prison dining area, are told that they will be all put in isolation cells and then will be interrogated one by one in a room containing a light with an on/off switch. The prisoners may communicate with one another by toggling the light switch (and that is the only way in which they can communicate). The light is initially switched off. There is no fixed order of interrogation, or interval between interrogations, and the same prisoner may be interrogated again at any stage. When interrogated, a prisoner can either do nothing, or toggle the light switch, or announce that all prisoners have been interrogated. If that announcement is true, the prisoners will (all) be set free, but if it is false, they will all be executed. While still in the dining room, and before the prisoners go to their isolation cells (forever), can the prisoners agree on a protocol that will set them free? At first glance, this riddle may seem impossible to solve: how can all of the necessary in...

  5. Three-dimensional point-cloud room model in room acoustics simulations

    DEFF Research Database (Denmark)

    Markovic, Milos; Olesen, Søren Krarup; Hammershøi, Dorte

    2013-01-01

    acquisition and its representation with a 3D point-cloud model, as well as utilization of such a model for the room acoustics simulations. A room is scanned with a commercially available input device (Kinect for Xbox360) in two different ways; the first one involves the device placed in the middle of the room...... and rotated around the vertical axis while for the second one the device is moved within the room. Benefits of both approaches were analyzed. The device's depth sensor provides a set of points in a three-dimensional coordinate system which represents scanned surfaces of the room interior. These data are used...... to build a 3D point-cloud model of the room. Several models are created to meet requirements of different room acoustics simulation algorithms: plane fitting and uniform voxel grid for geometric methods and triangulation mesh for the numerical methods. Advantages of the proposed method over the traditional...

  6. Three-dimensional point-cloud room model for room acoustics simulations

    DEFF Research Database (Denmark)

    Markovic, Milos; Olesen, Søren Krarup; Hammershøi, Dorte

    2013-01-01

    acquisition and its representation with a 3D point-cloud model, as well as utilization of such a model for the room acoustics simulations. A room is scanned with a commercially available input device (Kinect for Xbox360) in two different ways; the first one involves the device placed in the middle of the room...... and rotated around the vertical axis while for the second one the device is moved within the room. Benefits of both approaches were analyzed. The device's depth sensor provides a set of points in a three-dimensional coordinate system which represents scanned surfaces of the room interior. These data are used...... to build a 3D point-cloud model of the room. Several models are created to meet requirements of different room acoustics simulation algorithms: plane fitting and uniform voxel grid for geometric methods and triangulation mesh for the numerical methods. Advantages of the proposed method over the traditional...

  7. Power-managed smart lighting using a semantic interoperability architecture

    NARCIS (Netherlands)

    Bhardwaj, S.; Syed, Aly; Ozcelebi, T.; Lukkien, J.J.

    2011-01-01

    We present a power-managed smart lighting system that allows collaboration of Consumer Electronics (CE) lighting-devices and corresponding system architectures provided by different CE suppliers. In the example scenario, the rooms of a building are categorized as low- and highpriority, each category

  8. 9 CFR 590.548 - Drying, blending, packaging, and heat treatment rooms and facilities.

    Science.gov (United States)

    2010-01-01

    ... rooms shall be well-lighted and have ceilings and walls of a tile surface, enamel paint, or other water-resistant material. (1) The floors shall be free from cracks or rough surfaces where water or dirt could...

  9. Estimated health impact of a shift from light fuel to residential wood-burning in Upper Austria.

    Science.gov (United States)

    Haluza, Daniela; Kaiser, August; Moshammer, Hanns; Flandorfer, Claudia; Kundi, Michael; Neuberger, Manfred

    2012-07-01

    The dependency on carbon-based fossil energy and growing awareness of climate change issues has induced ambitious policy initiatives to promote renewable energy sources for indoor heating. Combustion of regionally available material such as wood is considered a carbon-neutral alternative for oil and gas, but unregulated revival of wood stoves may cause detrimental health effects. For the prognosis of the health impact of air pollution due to the use of wood stoves, Upper Austria served for a case study. On the basis of recent measurements of particulate matter fuel oil by either fossil gas or biomass, and for scenario 3, replacement of light fuel oil by biomass only. Compared with the current exposure from scenario 1, the increased annual mean PM10 levels are estimated to lead to 101 (95% CI 56;146) and 174 (95% CI 92;257) additional deaths among 1.4 million inhabitants per year for scenarios 2 and 3, respectively. Without adequate strategies for reducing the emissions of domestic heating facilities, replacement of fossil energy sources could lead to an increased health risk.

  10. The question of an upper bound on entropy

    International Nuclear Information System (INIS)

    Qadir, A.

    1982-08-01

    We discuss the possibility, and significance, of an upper bound on entropy in the light of the arguments of Bekenstein and Unruh and Wald. We obtain a stricter bound than Bekenstein does, and point out some limitations with regard to its significance. (author)

  11. CFD analysis of the temperature field in emergency pump room in Loviisa NPP

    Energy Technology Data Exchange (ETDEWEB)

    Rämä, Tommi, E-mail: tommi.rama@fortum.com [Fortum Power and Heat, P.O.B. 100, FI-00048 Fortum (Finland); Toppila, Timo, E-mail: timo.toppila@fortum.com [Fortum Power and Heat, P.O.B. 100, FI-00048 Fortum (Finland); Kelavirta, Teemu, E-mail: teemu.kelavirta@fortum.com [Fortum Power and Heat, Loviisa Power Plant, P.O.B. 23, FI-07901 Loviisa (Finland); Martin, Pasi, E-mail: pasi.martin@fortum.com [Fortum Power and Heat, Loviisa Power Plant, P.O.B. 23, FI-07901 Loviisa (Finland)

    2014-11-15

    Highlights: • Laser scanned room geometry from Loviisa NPP was utilized for CFD simulation. • Uncertainty of CFD simulation was estimated using the Grid Convergence Index. • Measured temperature field of pump room was reproduced with CFD simulation. - Abstract: In the Loviisa Nuclear Power Plant (NPP) six emergency pumps belonging to the same redundancy are located in the same room. During a postulated accident the cooling of the room is needed as the engines of the emergency pumps generate heat. Cooling is performed with fans blowing air to the upper part of the room. Temperature limits have been given to the operating conditions of the main components in order to ensure their reliable operation. Therefore the temperature field of the room is important to know. Temperature measurements were made close to the most important components of the pump room to get a better understanding of the temperature field. For these measurements emergency pumps and cooling fan units were activated. To simulate conditions during a postulated accident additional warm-air heaters were used. Computational fluid dynamic (CFD) simulations were made to support plant measurements. For the CFD study one of the pump rooms of Loviisa NPP was scanned with a laser and this data converted to detailed 3-D geometry. Tetrahedral computation grid was created inside the geometry. Grid sensitivity studies were made, and the model was then validated against the power plant tests. With CFD the detailed temperature and flow fields of the whole room were produced. The used CFD model was able to reproduce the temperature field of the measurements. Two postulated accident cases were simulated. In the cases the operating cooling units were varied. The temperature profile of the room changes significantly depending on which units are cooling and which only circulating the air. The room average temperature stays approximately the same. The simulation results were used to ensure the acceptable operating

  12. 'No blue' LED solution for photolithography room illumination

    DEFF Research Database (Denmark)

    Ou, Haiyan; Corell, Dennis Dan; Dam-Hansen, Carsten

    2010-01-01

    This paper explored the feasibility of using a LED-based bulb as the illumination light source for photolithography room. A no-blue LED was designed, and the prototype was fabricated. The spectral power distribution of both the LED bulb and the yellow fluorescent tube was measured. Based on that...... color rendering ability than the YFT. Furthermore, LED solution has design flexibility to improve it further. The prototype has been tested with photoresist SU8-2005. Even after 15 days of illumination, no effect was observed. So this LED-based solution was demonstrated to be a very promising light......, colorimetric values were calculated and compared on terms of chromatic coordinates, correlated color temperature, color rendering index, and chromatic deviation. Gretagmacbeth color charts were used as a more visional way to compare the two light sources, which shows that our no-blue LED bulb has much better...

  13. Flexible deep-ultraviolet light-emitting diodes for significant improvement of quantum efficiencies by external bending

    KAUST Repository

    Shervin, Shahab

    2018-01-26

    Deep ultraviolet (DUV) light at the wavelength range of 250‒280 nm (UVC spectrum) is essential for numerous applications such as sterilization, purification, sensing, and communication. III-nitride-based DUV light-emitting diodes (DUV LEDs), like other solid-state lighting sources, offer a great potential to replace the conventional gas-discharged lamps with short lifetimes and toxic-element-bearing nature. However, unlike visible LEDs, the DUV LEDs are still suffering from low quantum efficiencies (QEs) and low optical output powers. In this work, reported is a new route to improve QEs of AlGaN-based DUV LEDs using mechanical flexibility of recently developed bendable thin-film structures. Numerical studies show that electronic band structures of AlGaN heterostructures and resulting optical and electrical characteristics of the devices can be significantly modified by external bending through active control of piezoelectric polarization. Internal quantum efficiency (IQE) is enhanced higher than three times, when the DUV LEDs are moderately bent to induce in-plane compressive strain in the heterostructure. Furthermore, efficiency droop at high injection currents is mitigated and turn-on voltage of diodes decreases with the same bending condition. The concept of bendable DUV LEDs with a controlled external strain can provide a new path for high-output-power and high-efficiency devices.

  14. Flexible deep-ultraviolet light-emitting diodes for significant improvement of quantum efficiencies by external bending

    KAUST Repository

    Shervin, Shahab; Oh, Seung Kyu; Park, Hyun Jung; Lee, Keon Hwa; Asadirad, Mojtaba; Kim, Seung Hwan; Kim, Jeomoh; Pouladi, Sara; Lee, Sung-Nam; Li, Xiaohang; Kwak, Joon-Seop; Ryou, Jae-Hyun

    2018-01-01

    Deep ultraviolet (DUV) light at the wavelength range of 250‒280 nm (UVC spectrum) is essential for numerous applications such as sterilization, purification, sensing, and communication. III-nitride-based DUV light-emitting diodes (DUV LEDs), like other solid-state lighting sources, offer a great potential to replace the conventional gas-discharged lamps with short lifetimes and toxic-element-bearing nature. However, unlike visible LEDs, the DUV LEDs are still suffering from low quantum efficiencies (QEs) and low optical output powers. In this work, reported is a new route to improve QEs of AlGaN-based DUV LEDs using mechanical flexibility of recently developed bendable thin-film structures. Numerical studies show that electronic band structures of AlGaN heterostructures and resulting optical and electrical characteristics of the devices can be significantly modified by external bending through active control of piezoelectric polarization. Internal quantum efficiency (IQE) is enhanced higher than three times, when the DUV LEDs are moderately bent to induce in-plane compressive strain in the heterostructure. Furthermore, efficiency droop at high injection currents is mitigated and turn-on voltage of diodes decreases with the same bending condition. The concept of bendable DUV LEDs with a controlled external strain can provide a new path for high-output-power and high-efficiency devices.

  15. UV-visible light photocatalytic properties of NaYF4:(Gd, Si)/TiO2 composites

    Science.gov (United States)

    Mavengere, Shielah; Kim, Jung-Sik

    2018-06-01

    In this study, a new novel composite photocatalyst of NaYF4:(Gd, Si)/TiO2 phosphor has been synthesized by two step method of solution combustion and sol-gel. The photocatalyst powders were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), UV-vis spectroscopy and photoluminescence (PL) spectroscopy. Raman spectroscopy confirmed the anatase TiO2 phase which remarkably increased with existence of yttrium silicate compounds between 800 cm-1 and 900 cm-1. Double-addition of Gd3+-Si4+ ions in NaYF4 host introduced sub-energy band levels with intense absorption in the ultraviolet (UV) light region. Photocatalytic activity was examined by exposing methylene blue (MB) solutions mixed with photocatalyst powders to 254 nm UV-C fluorescent lamp and 200 W visible lights. The UV and visible photocatalytic reactivity of the NaYF4:(Gd, 1% Si)/TiO2 phosphor composites showed enhanced MB degradation efficiency. The coating of NaYF4:(Gd, 1% Si) phosphor with TiO2 nanoparticles creates energy band bending at the phosphor/TiO2 interfaces. Thus, these composites exhibited enhanced absorption of UV/visible light and the separation of electron and hole pairs for efficient photocatalysis.

  16. Performance of radiant cooling ceiling combined with personalized ventilation in an office room: identification of thermal conditions

    DEFF Research Database (Denmark)

    Lipczynska, Aleksandra; Kaczmarczyk, Jan; Melikov, Arsen Krikor

    2014-01-01

    were performed in a test room arranged as an office with 2 workstations and 2 seating occupants resembled by thermal manikins. Heat gain of 66-72 W/m2 was simulated in the room (occupants, computers, lighting, solar gain). The air temperature in the chamber was maintained at 26°C and 28°C. Personalized...

  17. Experimental analysis on a 1:2 scale model of the double light pipe, an innovative technological device for daylight transmission

    Energy Technology Data Exchange (ETDEWEB)

    Baroncini, C.; Boccia, O.; Chella, F.; Zazzini, P. [D.S.S.A.R.R. Faculty of Architecture, University ' ' G. D' Annunzio' ' Viale Pindaro 42, 65127 Pescara (Italy)

    2010-02-15

    In this paper the authors present the double light pipe, an innovative technological device, designed as an evolution of a traditional light pipe, which distributes daylight to underground areas of a building, illuminating, at the same time, the passage areas thanks to a larger collector and a second transparent pipe attached to the first one. Unlike the traditional light pipe, thanks to this double illuminating function it can be located in the middle of a room, despite its encumbrance. In this paper the technological design of the double light pipe is presented and the results of an experimental analysis on a reduced scale (1:2) model are shown. Internal illuminance data over horizontal and vertical work-planes were measured in various sky conditions with or without direct solar radiation. Being this innovative device obtained by a light pipe integrated with a second pipe, it performs like a traditional light pipe for the final room and, at the same time, illuminates the intermediate room giving it uniform and high quality light, particularly indicated for wide plant areas, such as show-rooms or museums. (author)

  18. Measuring light spectrum as a main indicator of artificial sources quality

    Directory of Open Access Journals (Sweden)

    Piotr Dąbrowski

    2015-05-01

    Full Text Available Objective: To compare different artificial light sources in different places where plant breeding is conduced. Methods: Measurements were conducted outdoor, in room, in greenhouse, under four panels with light emitting diodes, in phytotron, in dark room with various light sources and inside Sanyo versatile environmental chamber. The measurements were made by using SpectraPen SP100 (PSI, Czech Republic device. Results: Our result showed that spectrum measured outdoor during sunny day had only one peak at the wavelength of 485 nm (ca. 60000 relative units. On cloudy day, the trend of light spectrum curve was similar, but with lower values. At room conditions, the curve was more flat than outdoor. Under greenhouse conditions, the curve was similar to that measured outdoor. A few additional peaks on the curve appeared by adding high pressure sodium lamp. There were changes of curve under LED panels. Conclusions: It must be underlined that the most similar spectrum curve to daylight light has incandescent bulb and this light source should be preferred as support of daylight in greenhouses and as main source in phytotrons. Using high pressure sodium lamp in greenhouses as support of daylight cause increase in the red/far-red ratio and occurrence of a new peak on spectrum curve. The new possibilities are creating by LED panels with red and blue diodes.

  19. Analysis of mutant frequencies and mutation spectra in hMTH1 knockdown TK6 cells exposed to UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Fotouhi, Asal [Center for Radiation Protection Research, Department of Molecular Biosciences, Wenner-Gren Institute, Stockholm University (Sweden); Hagos, Winta Woldai [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Ilic, Marina; Wojcik, Andrzej; Harms-Ringdahl, Mats [Center for Radiation Protection Research, Department of Molecular Biosciences, Wenner-Gren Institute, Stockholm University (Sweden); Gruijl, Frank de [Department of Dermatology, Leiden University Medical Center, Leiden (Netherlands); Mullenders, Leon; Jansen, Jacob G. [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Haghdoost, Siamak, E-mail: Siamak.Haghdoost@su.se [Center for Radiation Protection Research, Department of Molecular Biosciences, Wenner-Gren Institute, Stockholm University (Sweden)

    2013-11-15

    Highlights: • hMTH1 protects cells from mutagenesis induced by UVA and UVB, but not UVC. • No protective role of hMTH1 in cell survival post UVB and UVC irradiation. • hMTH1 prevents induction of transition-type mutations at AT and GC post UVA irradiation. • 2-OH-dATP rather than 8-oxo-dGTP in the nucleotide pool likely contributes in UVA-induced mutations. - Abstract: Ultraviolet radiation is a highly mutagenic agent that damages the DNA by the formation of mutagenic photoproducts at dipyrimidine sites and by oxidative DNA damages via reactive oxygen species (ROS). ROS can also give rise to mutations via oxidation of dNTPs in the nucleotide pool, e.g. 8-oxo-dGTP and 2-OH-dATP and subsequent incorporation during DNA replication. Here we show that expression of human MutT homolog 1 (hMTH1) which sanitizes the nucleotide pool by dephosphorylating oxidized dNTPs, protects against mutagenesis induced by long wave UVA light and by UVB light but not by short wave UVC light. Mutational spectra analyses of UVA-induced mutations at the endogenous Thymidine kinase gene in human lymphoblastoid cells revealed that hMTH1 mainly protects cells from transitions at GC and AT base pairs.

  20. Humic Acid Degradation by ZnO Photocatalyst

    Directory of Open Access Journals (Sweden)

    Sekartaji Putri A.

    2016-01-01

    Full Text Available Humic acid (HA is universally present in soils and natural water resources in a yellow-brown form. HA can react with chlorine during drinking water treatment and produce disinfection byproducts (DBPs, such as trihalomethanes (THMs and haloacetic acids (HAAs, which are harmful for health. Therefore, HA has to be eliminated from water environment. The photocatalysis is an effective alternative solution for the degradation of HA in a water environment. This research aims to degrade HA from water environment. The rapid degradation of HA, using zinc oxide nanoparticles, irradiated by ultraviolet light (ZnO/UV, is investigated. The optimum conditions of pertinent factors, which include the light wavelength (UV-A and UV-C, and light intensity, HA concentration, ZnO dose, and contact time are investigated at neutral pH conditions, considered for drinking water treatment. HA degradation efficiency reached more than 80% after 60 min for both types of irradiation in optimum conditions of 0.3 g/L ZnO dose in 180 min of contact time. Comparisons for degradation efficiency under UV-A and UV-C irradiation indicate that UV-C has higher efficiency, up to 150 min of contact time. The reusability of catalyst is performed for three reuses and still revealed effective for beneficial commercial applications.

  1. Room-temperature deposition of crystalline patterned ZnO films by confined dewetting lithography

    International Nuclear Information System (INIS)

    Sepulveda-Guzman, S.; Reeja-Jayan, B.; De la Rosa, E.; Ortiz-Mendez, U.; Reyes-Betanzo, C.; Cruz-Silva, R.; Jose-Yacaman, M.

    2010-01-01

    In this work patterned ZnO films were prepared at room-temperature by deposition of ∼5 nm size ZnO nanoparticles using confined dewetting lithography, a process which induces their assembly, by drying a drop of ZnO colloidal dispersion between a floating template and the substrate. Crystalline ZnO nanoparticles exhibit a strong visible (525 nm) light emission upon UV excitation (λ = 350 nm). The resulting films were characterized by scanning electron microscopy (SEM) and atomic force microscope (AFM). The method described herein presents a simple and low cost method to prepare crystalline ZnO films with geometric patterns without additional annealing. Such transparent conducting films are attractive for applications like light emitting diodes (LEDs). As the process is carried out at room temperature, the patterned crystalline ZnO films can even be deposited on flexible substrates.

  2. Room-temperature deposition of crystalline patterned ZnO films by confined dewetting lithography

    Energy Technology Data Exchange (ETDEWEB)

    Sepulveda-Guzman, S., E-mail: selene.sepulvedagz@uanl.edu.mx [Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia. UANL, PIIT Monterrey, CP 66629, Apodaca NL (Mexico); Reeja-Jayan, B. [Texas Materials Institute, University of Texas at Austin, Austin, TX 78712 (United States); De la Rosa, E. [Centro de Investigacion en Optica, Loma del Bosque 115 Col. Lomas del Campestre C.P. 37150 Leon, Gto. Mexico (Mexico); Ortiz-Mendez, U. [Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia. UANL, PIIT Monterrey, CP 66629, Apodaca NL (Mexico); Reyes-Betanzo, C. [Instituto Nacional de Astrofisica Optica y Electronica, Calle Luis Enrique Erro No. 1, Santa Maria Tonanzintla, Puebla. Apdo. Postal 51 y 216, C.P. 72000 Puebla (Mexico); Cruz-Silva, R. [Centro de Investigacion en Ingenieria y Ciencias Aplicadas, UAEM. Av. Universidad 1001, Col. Chamilpa, CP 62210 Cuernavaca, Mor. (Mexico); Jose-Yacaman, M. [Physics and Astronomy Department University of Texas at San Antonio 1604 campus San Antonio, TX 78249 (United States)

    2010-03-15

    In this work patterned ZnO films were prepared at room-temperature by deposition of {approx}5 nm size ZnO nanoparticles using confined dewetting lithography, a process which induces their assembly, by drying a drop of ZnO colloidal dispersion between a floating template and the substrate. Crystalline ZnO nanoparticles exhibit a strong visible (525 nm) light emission upon UV excitation ({lambda} = 350 nm). The resulting films were characterized by scanning electron microscopy (SEM) and atomic force microscope (AFM). The method described herein presents a simple and low cost method to prepare crystalline ZnO films with geometric patterns without additional annealing. Such transparent conducting films are attractive for applications like light emitting diodes (LEDs). As the process is carried out at room temperature, the patterned crystalline ZnO films can even be deposited on flexible substrates.

  3. Modern control room design experience and speculation

    International Nuclear Information System (INIS)

    Smith, J.E.

    1993-01-01

    Can operators trained to use conventional control panels readily adapt to CRT based control rooms? Does automation make the design of good man-machine interfaces more or less difficult? In a conventional, hard-wired control room is the operator's peripheral vision always an asset and how can one do better in a CRT based control room? Are Expert System assisted man-machine interfaces a boon or a bust? This paper explores these questions in the light of actual experience with advanced power plant control environments. This paper discusses how automation has in fact simplified the problem of ensuring that the operator has at all times a clear understanding of the plant state. The author contends that conventional hard-wired control rooms are very poor at providing the operator with a good overview of the plant status particularly under startup, or upset conditions and that CRT-based control rooms offer an opportunity for improvement. Experience with some early attempts at this are discussed together with some interesting proposals from other authors. Finally the paper discusses the experience to date with expert system assisted man-machine interfaces. Although promising for the future progress has been slow. The amount of knowledge research required is often formidable and consequently costly. Often when an adequate knowledge base is finally acquired it turns out to be better to use it to increase the level of automation and thus simplify the operator's task. The risks are not any greater and automation offers more consistent operation. It is important also to carefully distinguish between expert system assisted display selection and expert system operator guidance. The first is intended to help the operator in his quest for information. The second attempts to guide the operator actions. The good and the bad points of each of these approaches is discussed

  4. Power-managed smart lighting using a semantic interoperability architecture

    NARCIS (Netherlands)

    Bhardwaj, S.; Syed, Aly; Ozcelebi, T.; Lukkien, J.J.

    2011-01-01

    This paper presents a power-managed smart lighting system that allows collaboration of lighting consumer electronics (CE) devices and corresponding system architectures provided by different CE suppliers. In the example scenario, the rooms of a building are categorized as low and high priority, each

  5. Design of an automatic solar lighting system | Rais | Journal of ...

    African Journals Online (AJOL)

    The system can be applied to the room light, outdoor light, corridor light, spotlight or streetlight. The system is low cost and beneficial for home usage to save electricity bills and when the occupants are absent for relatively long period of time. Keywords: renewable energy; solar energy; green technology; sustainable; dark on ...

  6. Study of low noise preamplifier systems for use with room temperature mercuric iodide (HgI2) x-ray detectors

    International Nuclear Information System (INIS)

    Iwanczyk, J.S.; Dabrowski, A.J.; Huth, G.C.; Del Duca, A.; Schenpple, W.

    1980-01-01

    An analysis of different preamplification systems for use with room temperature mercuric iodide x-ray detectors has been performed. Resistor-, drain-, and light-feedback preamplifiers have been studied. Energy resolution of 295 eV (FWHM) for Fe-55 source (5.9 keV) and 225 eV (FWHM) for the pulser have been obtained with both the detector and the input FET at room temperature using the pulsed-light feedback preamplifier. It has been shown that cooling the input FET using a small Peltier element allows the energy resolution to be improved up to 25%

  7. Room with a View: Ethical Encounters in Room 13

    Science.gov (United States)

    Grube, Vicky

    2012-01-01

    In this article, the author describes ethical encounters in Room 13, a schoolroom where children made what they wanted, posed their own questions, and ran an art room like a small business. In Room 13 children had the responsibility to maintain all aspects of the art studio. Specific decisions fell to an annually elected management team, a small…

  8. The Effects of Interior Design on Communication and Impressions of a Counselor in a Counseling Room

    Science.gov (United States)

    Miwa, Yoshiko; Hanyu, Kazunori

    2006-01-01

    This study aimed to investigate effects of the interior design of a counseling room on participants' self-disclosure and impressions of a counselor. The authors examined the effects of lighting and decorations. It tested four conditions crossing decorations (with or without home-like decorations) and type of lighting (bright or dim). Eighty…

  9. Operating room management and operating room productivity: the case of Germany.

    Science.gov (United States)

    Berry, Maresi; Berry-Stölzle, Thomas; Schleppers, Alexander

    2008-09-01

    We examine operating room productivity on the example of hospitals in Germany with independent anesthesiology departments. Linked to anesthesiology group literature, we use the ln(Total Surgical Time/Total Anesthesiologists Salary) as a proxy for operating room productivity. We test the association between operating room productivity and different structural, organizational and management characteristics based on survey data from 87 hospitals. Our empirical analysis links improved operating room productivity to greater operating room capacity, appropriate scheduling behavior and management methods to realign interests. From this analysis, the enforcing jurisdiction and avoiding advance over-scheduling appear to be the implementable tools for improving operating room productivity.

  10. Room temperature lasing unraveled by a strong resonance between gain and parasitic absorption in uniaxially strained germanium

    Science.gov (United States)

    Gupta, Shashank; Nam, Donguk; Vuckovic, Jelena; Saraswat, Krishna

    2018-04-01

    A complementary metal-oxide semiconductor compatible on-chip light source is the holy grail of silicon photonics and has the potential to alleviate the key scaling issues arising due to electrical interconnects. Despite several theoretical predictions, a sustainable, room temperature laser from a group-IV material is yet to be demonstrated. In this work, we show that a particular loss mechanism, inter-valence-band absorption (IVBA), has been inadequately modeled until now and capturing its effect accurately as a function of strain is crucial to understanding light emission processes from uniaxially strained germanium (Ge). We present a detailed model of light emission in Ge that accurately models IVBA in the presence of strain and other factors such as polarization, doping, and carrier injection, thereby revising the road map toward a room temperature Ge laser. Strikingly, a special resonance between gain and loss mechanisms at 4%-5% 〈100 〉 uniaxial strain is found resulting in a high net gain of more than 400 cm-1 at room temperature. It is shown that achieving this resonance should be the goal of experimental work rather than pursuing a direct band gap Ge.

  11. Comparison and mechanism of photocatalytic activities of N-ZnO and N-ZrO2 for the degradation of rhodamine 6G.

    Science.gov (United States)

    Sudrajat, Hanggara; Babel, Sandhya

    2016-05-01

    N-doped ZnO (N-ZnO) and N-doped ZrO2 (N-ZrO2) are synthesized by novel, simple thermal decomposition methods. The catalysts are evaluated for the degradation of rhodamine 6G (R6G) under visible and UV light. N-ZnO exhibits higher dye degradation under both visible and UV light compared to N-ZrO2 due to possessing higher specific surface area, lower crystalline size, and lower band gap. However, it is less reusable than N-ZrO2 and its photocatalytic activity is also deteriorated at low pH. At the same intensity of 3.5 W/m(2), UVC light is shown to be a better UV source for N-ZnO, while UVA light is more suitable for N-ZrO2. At pH 7 with initial dye concentration of 10 mg/L, catalyst concentration of 1 g/L, and UVC light, 94.3 % of R6G is degraded by N-ZnO within 2 h. Using UVA light under identical experimental conditions, 93.5 % degradation of R6G is obtained by N-ZrO2. Moreover, the type of light source is found to determine the reactive species produced in the R6G degradation by N-ZnO and N-ZrO2. Less oxidative reactive species such as superoxide radical and singlet oxygen play a major role in the degradation of R6G under visible light. On the contrary, highly oxidative hydroxyl radicals are predominant under UVC light. Based on the kinetic study, the adsorption of R6G on the catalyst surface is found to be the controlling step.

  12. Diagnostic distribution of non-traumatic upper limb disorders

    DEFF Research Database (Denmark)

    Laursen, Lise H; Sjøgaard, Gisela; Hagert, C G

    2007-01-01

    BACKGROUND: Upper limb disorders (ULDs) are common, and so are the difficulties in specific diagnoses of these disorders. Prior studies have shed light on the nerves in the diagnostic approach beside disorders related to muscles, tendons and joints (MCDs). OBJECTIVE: The study aimed to compare th...

  13. Hole-exciton interaction induced high field decay of magneto-electroluminescence in Alq{sub 3}-based organic light-emitting diodes at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Tingting; Holford, D. F.; Gu, Hang; Kreouzis, T. [Materials Research Institute and School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); Zhang, Sijie, E-mail: Sijie.zhang@scu.edu.cn, E-mail: w.gillin@qmul.ac.uk [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Gillin, W. P., E-mail: Sijie.zhang@scu.edu.cn, E-mail: w.gillin@qmul.ac.uk [Materials Research Institute and School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom); College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China)

    2016-01-11

    The magnetic field effects on the electroluminescence of aluminium tris-(8-hydroxyqinoline) (Alq{sub 3}) based organic light emitting diodes have been investigated by varying the electron/hole ratio in the emissive layer. Experimental results reveal that a negative high field effect in the magneto-electroluminescence (MEL) can be found in devices with very low triplet exciton concentration at room temperature. This suggests triplet-triplet annihilation cannot be used to explain the negative high field MEL in the Alq{sub 3} system. Our results suggest that hole-exciton interaction may be the origin of the negative high field MEL and also, in parallel with this interaction, there is also the more common positive high field process occurring which has been tentatively attributed to electron-exciton interactions. The competition between these different processes decides the final shape of the MEL at high fields.

  14. How Clean Are Hotel Rooms? Part I: Visual Observations vs. Microbiological Contamination.

    Science.gov (United States)

    Almanza, Barbara A; Kirsch, Katie; Kline, Sheryl Fried; Sirsat, Sujata; Stroia, Olivia; Choi, Jin Kyung; Neal, Jay

    2015-01-01

    Current evidence of hotel room cleanliness is based on observation rather than empirically based microbial assessment. The purpose of the study described here was to determine if observation provides an accurate indicator of cleanliness. Results demonstrated that visual assessment did not accurately predict microbial contamination. Although testing standards have not yet been established for hotel rooms and will be evaluated in Part II of the authors' study, potential microbial hazards included the sponge and mop (housekeeping cart), toilet, bathroom floor, bathroom sink, and light switch. Hotel managers should increase cleaning in key areas to reduce guest exposure to harmful bacteria.

  15. Lighting performance and electrical energy consumption of a virtual window prototype

    NARCIS (Netherlands)

    Mangkuto, R.A.; Wang, S.; Meerbeek, B.W.; Aries, M.B.C.; Loenen, van E.J.

    2014-01-01

    This article discusses the design and evaluation of a virtual window prototype, built using arrays of LED tiles to simulate the light as well as the view of a window. Arrays of white light LED fixtures with adjustable colour temperatures were incorporated to provide direct light into the test room.

  16. Electrically Injected Twin Photon Emitting Lasers at Room Temperature

    Directory of Open Access Journals (Sweden)

    Claire Autebert

    2016-08-01

    Full Text Available On-chip generation, manipulation and detection of nonclassical states of light are some of the major issues for quantum information technologies. In this context, the maturity and versatility of semiconductor platforms are important assets towards the realization of ultra-compact devices. In this paper we present our work on the design and study of an electrically injected AlGaAs photon pair source working at room temperature. The device is characterized through its performances as a function of temperature and injected current. Finally we discuss the impact of the device’s properties on the generated quantum state. These results are very promising for the demonstration of electrically injected entangled photon sources at room temperature and let us envision the use of III-V semiconductors for a widespread diffusion of quantum communication technologies.

  17. Visible optical radiation generates bactericidal effect applicable for inactivation of health care associated germs demonstrated by inactivation of E. coli and B. subtilis using 405-nm and 460-nm light emitting diodes

    Science.gov (United States)

    Hönes, Katharina; Stangl, Felix; Sift, Michael; Hessling, Martin

    2015-07-01

    The Ulm University of Applied Sciences is investigating a technique using visible optical radiation (405 nm and 460 nm) to inactivate health-hazardous bacteria in water. A conceivable application could be point-of-use disinfection implementations in developing countries for safe drinking water supply. Another possible application field could be to provide sterile water in medical institutions like hospitals or dental surgeries where contaminated pipework or long-term disuse often results in higher germ concentrations. Optical radiation for disinfection is presently mostly used in UV wavelength ranges but the possibility of bacterial inactivation with visible light was so far generally disregarded. One of the advantages of visible light is, that instead of mercury arc lamps, light emitting diodes could be used, which are commercially available and therefore cost-efficient concerning the visible light spectrum. Furthermore they inherit a considerable longer life span than UV-C LEDs and are non-hazardous in contrast to mercury arc lamps. Above all there are specific germs, like Bacillus subtilis, which show an inactivation resistance to UV-C wavelengths. Due to the totally different deactivation mechanism even higher disinfection rates are reached, compared to Escherichia coli as a standard laboratory germ. By 460 nm a reduction of three log-levels appeared with Bacillus subtilis and a half log-level with Escherichia coli both at a dose of about 300 J/cm². By the more efficient wavelength of 405 nm four and a half log-levels are reached with Bacillus subtilis and one and a half log-level with Escherichia coli also both at a dose of about 300 J/cm². In addition the employed optical setup, which delivered a homogeneous illumination and skirts the need of a stirring technique to compensate irregularities, was an important improvement compared to previous published setups. Evaluated by optical simulation in ZEMAX® the designed optical element provided proven

  18. Numerical Prediction of Airflow in a Room with Ceiling-Mounted Obstacles

    DEFF Research Database (Denmark)

    Svidt, Kjeld

    In ventilated rooms the air inlet device is often placed close to the ceiling. The air inlet will form a wall jet or a reattached wall jet. The wall jet may be disturbed by ceilingmounted obstacles such as light fittings or ceiling beams which, in some cases, can cause the air jet to be deflected...

  19. Ultrastrong light-matter coupling in electrically doped microcavity organic light emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Mazzeo, M., E-mail: marco.mazzeo@unisalento.it [Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento, Via Monteroni, 73100 Lecce (Italy); NNL, Istituto Nanoscienze - CNR, Via Arnesano, 73100 Lecce (Italy); Genco, A. [Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento, Via Monteroni, 73100 Lecce (Italy); Gambino, S. [NNL, Istituto Nanoscienze - CNR, Via Arnesano, 73100 Lecce (Italy); CBN, Istituto Italiano Tecnologia, Via Barsanti 1, 73010 Lecce (Italy); Ballarini, D.; Mangione, F.; Sanvitto, D. [NNL, Istituto Nanoscienze - CNR, Via Arnesano, 73100 Lecce (Italy); Di Stefano, O.; Patanè, S.; Savasta, S. [Dipartimento di Fisica e Scienze della Terra, Università di Messina, Viale F. Stagno d' Alcontres 31, 98166 Messina (Italy); Gigli, G. [Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento, Via Monteroni, 73100 Lecce (Italy); NNL, Istituto Nanoscienze - CNR, Via Arnesano, 73100 Lecce (Italy); CBN, Istituto Italiano Tecnologia, Via Barsanti 1, 73010 Lecce (Italy)

    2014-06-09

    The coupling of the electromagnetic field with an electronic transition gives rise, for strong enough light-matter interactions, to hybrid states called exciton-polaritons. When the energy exchanged between light and matter becomes a significant fraction of the material transition energy an extreme optical regime called ultrastrong coupling (USC) is achieved. We report a microcavity embedded p-i-n monolithic organic light emitting diode working in USC, employing a thin film of squaraine dye as active layer. A normalized coupling ratio of 30% has been achieved at room temperature. These USC devices exhibit a dispersion-less angle-resolved electroluminescence that can be exploited for the realization of innovative optoelectronic devices. Our results may open the way towards electrically pumped polariton lasers.

  20. Control of the Environment in the Operating Room.

    Science.gov (United States)

    Katz, Jonathan D

    2017-10-01

    There is a direct relationship between the quality of the environment of a workplace and the productivity and efficiency of the work accomplished. Components such as temperature, humidity, ventilation, drafts, lighting, and noise each contribute to the quality of the overall environment and the sense of well-being of those who work there.The modern operating room is a unique workplace with specific, and frequently conflicting, environmental requirements for each of the inhabitants. Even minor disturbances in the internal environment of the operating room can have serious ramifications on the comfort, effectiveness, and safety of each of the inhabitants. A cool, well-ventilated, and dry climate is optimal for many members of the surgical team. Any significant deviation from these objectives raises the risk of decreased efficiency and productivity and adverse surgical outcomes. A warmer, more humid, and quieter environment is necessary for the patient. If these requirements are not met, the risk of surgical morbidity and mortality is increased. An important task for the surgical team is to find the correct balance between these 2 opposed requirements. Several of the components of the operating room environment, especially room temperature and airflow patterns, are easily manipulated by the members of the surgical team. In the following discussion, we will examine these elements to better understand the clinical ramifications of adjustments and accommodations that are frequently made to meet the requirements of both the surgical staff and the patient.

  1. Ultraviolet-C efficacy against a norovirus surrogate and hepatitis A virus on a stainless steel surface.

    Science.gov (United States)

    Park, Shin Young; Kim, An-Na; Lee, Ki-Hoon; Ha, Sang-Do

    2015-10-15

    In this study, the effects of 10-300 mWs/cm(2) of ultraviolet radiation (UV-C) at 260 nm were investigated for the inactivation of two foodborne viruses: murine norovirus-1 (MNV-1; a human norovirus [NoV] surrogate) and hepatitis A virus (HAV). We used an experimentally contaminated stainless steel surface, a common food-contact surface, to examine the effects of low doses of UV-C radiation on MNV-1 and HAV titers. The modified Gompertz equation was used to generate non-linear survival curves and calculate dR-values as the UV-C dose of 90% reduction for MNV-1 (R(2)=0.95, RMSE=0.038) and HAV (R(2)=0.97, RMSE=0.016). Total MNV-1 and HAV titers significantly decreased (pradiation than MNV-1. These data suggest that low doses of UV-C light on food contact surfaces could be effective to inactivate human NoV and HAV in restaurant, institutional, and industrial kitchens and facilities. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Room-Temperature Quantum Ballistic Transport in Monolithic Ultrascaled Al-Ge-Al Nanowire Heterostructures.

    Science.gov (United States)

    Sistani, Masiar; Staudinger, Philipp; Greil, Johannes; Holzbauer, Martin; Detz, Hermann; Bertagnolli, Emmerich; Lugstein, Alois

    2017-08-09

    Conductance quantization at room temperature is a key requirement for the utilizing of ballistic transport for, e.g., high-performance, low-power dissipating transistors operating at the upper limit of "on"-state conductance or multivalued logic gates. So far, studying conductance quantization has been restricted to high-mobility materials at ultralow temperatures and requires sophisticated nanostructure formation techniques and precise lithography for contact formation. Utilizing a thermally induced exchange reaction between single-crystalline Ge nanowires and Al pads, we achieved monolithic Al-Ge-Al NW heterostructures with ultrasmall Ge segments contacted by self-aligned quasi one-dimensional crystalline Al leads. By integration in electrostatically modulated back-gated field-effect transistors, we demonstrate the first experimental observation of room temperature quantum ballistic transport in Ge, favorable for integration in complementary metal-oxide-semiconductor platform technology.

  3. Ge-Based Spin-Photodiodes for Room-Temperature Integrated Detection of Photon Helicity

    KAUST Repository

    Rinaldi, Christian

    2012-05-02

    Spin-photodiodes based on Fe/MgO/Ge(001) heterostructures are reported. These devices perform the room-temperature integrated electrical detection of the spin polarization of a photocurrent generated by circularly polarized photons with a wavelength of 1300 nm, for light pulses with intensity I 0 down to 200 μW. A forward and reverse-biased average photocurrent variation of 5.9% is measured for the complete reversal of the incident light helicity. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Hypoxia Room

    Data.gov (United States)

    Federal Laboratory Consortium — The Hypoxia Room is a 8x8x8 ft. clear vinyl plastic and aluminum frame construction enclosure located within USAREIM laboratory 028. The Hypoxia Room (manufactured...

  5. Effect of Room Ventilation Rates in Rodent Rooms with Direct-Exhaust IVC Systems.

    Science.gov (United States)

    Geertsema, Roger S; Lindsell, Claire E

    2015-09-01

    When IVC are directly exhausted from a rodent housing room, the air quality of the room can become independent of the intracage air quality and may reduce the need for high room ventilation rates. This study assessed the effect of decreasing the ventilation rate in rodent rooms using direct-exhaust IVC systems. The study was conducted over 16 wk and compared conditions in 8 rodent rooms that had ventilation rates of 5 to 6 air changes per hour (ACH) with those in rooms at 10 to 12 ACH. At the low ventilation rate, rooms had higher CO₂ concentrations, higher dew point temperature, and lower particulate levels and spent a greater percentage of time above the temperature set point than did rooms at the high rate. The levels of allergens and endotoxins in room air were the same regardless of the ventilation rate. Differences seen in parameters within cages at the 2 ventilation rates were operationally irrelevant. We detected no total volatile organic compounds in the room that were attributable to ammonia, regardless of the ventilation rate. Clearing the air of ethanol after a spill took longer at the low compared with high rate. However, ethanol clearance was faster at the low rate when the demand-control system was activated than at the high ventilation rate alone. Air quality in the room and in the cages were acceptable with room ventilation rates of 5 to 6 ACH in rodent rooms that use direct-exhaust IVC systems.

  6. Photovoltaic powered ultraviolet and visible light-emitting diodes for sustainable point-of-use disinfection of drinking waters.

    Science.gov (United States)

    Lui, Gough Yumu; Roser, David; Corkish, Richard; Ashbolt, Nicholas; Jagals, Paul; Stuetz, Richard

    2014-09-15

    For many decades, populations in rural and remote developing regions will be unable to access centralised piped potable water supplies, and indeed, decentralised options may be more sustainable. Accordingly, improved household point-of-use (POU) disinfection technologies are urgently needed. Compared to alternatives, ultraviolet (UV) light disinfection is very attractive because of its efficacy against all pathogen groups and minimal operational consumables. Though mercury arc lamp technology is very efficient, it requires frequent lamp replacement, involves a toxic heavy metal, and their quartz envelopes and sleeves are expensive, fragile and require regular cleaning. An emerging alternative is semiconductor-based units where UV light emitting diodes (UV-LEDs) are powered by photovoltaics (PV). Our review charts the development of these two technologies, their current status, and challenges to their integration and POU application. It explores the themes of UV-C-LEDs, non-UV-C LED technology (e.g. UV-A, visible light, Advanced Oxidation), PV power supplies, PV/LED integration and POU suitability. While UV-C LED technology should mature in the next 10 years, research is also needed to address other unresolved barriers to in situ application as well as emerging research opportunities especially UV-A, photocatalyst/photosensitiser use and pulsed emission options. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Room temperature superconductors

    International Nuclear Information System (INIS)

    Sleight, A.W.

    1995-01-01

    If the Holy Grail of room temperature superconductivity could be achieved, the impact on could be enormous. However, a useful room temperature superconductor for most applications must possess a T c somewhat above room temperature and must be capable of sustaining superconductivity in the presence of magnetic fields while carrying a significant current load. The authors will return to the subject of just what characteristics one might seek for a compound to be a room temperature superconductor. 30 refs., 3 figs., 1 tab

  8. Prognostic factors for perioperative pulmonary events among patients undergoing upper abdominal surgery

    Directory of Open Access Journals (Sweden)

    Rafael Luis Sakai

    Full Text Available CONTEXT AND OBJECTIVE: The significant relationship between upper abdominal surgery and early (perioperative pulmonary events was investigated among patients with preoperative pulmonary conditions undergoing general anesthesia. DESIGN AND SETTING: Retrospective study for which data were obtained prospectively from 1999 to 2004, at a tertiary university hospital. METHODS: We retrospectively studied 3107 patients over 11 years old presenting American Society of Anesthesiologists (ASA status I, II or III who underwent upper abdominal surgery under general anesthesia and were discharged to the recovery room. The preoperative conditions analyzed using logistic regression were: age, sex, ASA physical status, congestive heart failure, asthma, chronic obstructive pulmonary disease (COPD, respiratory failure and smoking. The outcomes or dependent variables included intraoperative and postoperative events: bronchospasm, hypoxemia, hypercapnia, prolonged intubation and airway secretion. RESULTS: Among these patients (1500 males, 1607 females, mean age 48 years, 1088 ASA I, 1402 ASA II and 617 ASA III, there were 80 congestive heart failures, 82 asthmatics, 122 with COPD, 21 respiratory failures and 428 smokers. Logistic regression analysis showed that female sex (p < 0.001, age over 70 years (p < 0.01, smoking (p < 0.001 and COPD (p < 0.02 significantly influenced pulmonary event development, particularly hypoxemia and bronchospasm, at both times but not in the same patients. Asthma and congestive heart failure cases did not present pulmonary events in the recovery room. CONCLUSION: In upper abdominal surgery under general anesthesia, female sex, age over 70, smoking and COPD were independent risk factors for intra and postoperative pulmonary events.

  9. Enhancing the Performance of Quantum Dot Light-Emitting Diodes Using Room-Temperature-Processed Ga-Doped ZnO Nanoparticles as the Electron Transport Layer

    KAUST Repository

    Cao, Sheng

    2017-04-19

    Colloidal ZnO nanoparticle (NP) films are recognized as efficient electron transport layers (ETLs) for quantum dot light-emitting diodes (QD-LEDs) with good stability and high efficiency. However, because of the inherently high work function of such films, spontaneous charge transfer occurs at the QD/ZnO interface in such a QD-LED, thus leading to reduced performance. Here, to improve the QD-LED performance, we prepared Ga-doped ZnO NPs with low work functions and tailored band structures via a room-temperature (RT) solution process without the use of bulky organic ligands. We found that the charge transfer at the interface between the CdSe/ZnS QDs and the doped ZnO NPs was significantly weakened because of the incorporated Ga dopants. Remarkably, the as-assembled QD-LEDs, with Ga-doped ZnO NPs as the ETLs, exhibited superior luminances of up to 44 000 cd/m2 and efficiencies of up to 15 cd/A, placing them among the most efficient red-light QD-LEDs ever reported. This discovery provides a new strategy for fabricating high-performance QD-LEDs by using RT-processed Ga-doped ZnO NPs as the ETLs, which could be generalized to improve the efficiency of other optoelectronic devices.

  10. Room acoustics modeling using a point-cloud representation of the room geometry

    DEFF Research Database (Denmark)

    Markovic, Milos; Olesen, Søren Krarup; Hammershøi, Dorte

    2013-01-01

    Room acoustics modeling is usually based on the room geometry that is parametrically described prior to a sound transmission calculation. This is a highly room-specific task and rather time consuming if a complex geometry is to be described. Here, a run time generic method for an arbitrary room...... geometry acquisition is presented. The method exploits a depth sensor of the Kinect device that provides a point based information of a scanned room interior. After post-processing of the Kinect output data, a 3D point-cloud model of the room is obtained. Sound transmission between two selected points...... level of user immersion by a real time acoustical simulation of a dynamic scenes....

  11. TUGAS ROOM ATTENDANT DALAM MENANGANI COMPLAINT TAMU DELUXE ROOM HOTEL HYAAT REGENCY BANDUNG

    Directory of Open Access Journals (Sweden)

    Reza Gustia Purnama

    2016-05-01

    Full Text Available Abstract - The problem is how meticulous the duties and responsibilities of the room attendant in the deluxe room Hotel Hyatt Regency Bandung, standard operational procedures in the deluxe room Hotel Hyatt Regency Bandung, and handling guest complaint in deluxe room Hotel Hyatt Regency Bandung. Author uses descriptive analysis, which is a form of writing in the actual situation describes strive about the object of research, then the data obtained in the form of a report compiled in. Based on the results of observation it can be concluded that the task and responsibility of the room attendant in the deluxe room Hyatt Regency Bandung already carry it out in accordance with standard operational procedures (SOP which is divided into two shifts, morning and evening shift which has a slightly different task, standard operational procedures in the deluxe room Hyatt Regency Bandung has been standard operating procedure in applying it at the hotel Hyatt Regency Bandung, and Guest complaint handling in deluxe room Hyatt Regency Bandung Hotel how to deal with and resolve the complaint vary slightly in view of the type of complaint. Based on the results of observation and discussion, the authors conclude that the Duty room attendant in handling customers compaint deluxe room in the Hyatt Regency Bandung Hotel when his handlers was conducted appropriately and propesional effects will be good for the image of the hyatt regency hotel bandung.   Keywords: Room Attendant, Complaint, Deluxe room   Abstraksi - Masalah yang di teliti adalah tugas dan tanggung jawab room attendant di deluxe room Hotel Hyatt Regency Bandung, standar operasional prosedur di deluxe room Hotel Hyatt Regency Bandung, dan penanganan complaint tamu di deluxe room Hotel Hyatt Regency Bandung.  Metode yang di gunakan menggunakan analisis deskriptif, yaitu bentuk penulisan yang di upayakan menggambarkan keadaan yang sebenarnya tetang objek penelitian,kemudian data yang di peroleh disusun

  12. Technical and Economic Aspects of Designing an Efficient Room Air-Conditioner Program in India

    Energy Technology Data Exchange (ETDEWEB)

    Abhyankar, Nikit [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Div.; Shah, Nihar [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Div.; Phadke, Amol [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Div.; Park, Won Young [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Div.

    2017-09-05

    Several studies have projected a massive increase in the demand for air conditioners (ACs) over the next two decades in India. By 2030, room ACs could add 140 GW to the peak load, equivalent to over 30% of the total projected peak load. Therefore, there is significant interest among policymakers, regulators, and utilities in managing room AC demand by enhancing energy efficiency. Building on the historical success of the Indian Bureau of Energy Efficiency’s star-labeling program, Energy Efficiency Services Limited recently announced a program to accelerate the sale of efficient room ACs using bulk procurement, similar to their successful UJALA light-emitting diode (LED) bulk procurement program. This report discusses some of the key considerations in designing a bulk procurement or financial incentive program for enhancing room AC efficiency in India. We draw upon our previous research to demonstrate the overall technical potential and price impact of room AC efficiency improvement and its technical feasibility in India. We also discuss the importance of using low global warming potential (GWP) refrigerants and smart AC equipment that is demand response (DR) ready.

  13. Sunscope natural light systems : tubular skylights

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    This brochure described a tubular skylight designed by Sunscope Natural Light Systems. The Sunscope is a super-reflective light system in which daylight is reflected down a cylinder to a translucent ceiling fixture that diffuses natural light throughout the room in which it is placed. The Sunscope requires no structure changes, is installed in less than 3 hours, and requires no drywall repairs or repainting. The system eliminates the need for daytime electric lighting, and causes no winter heat losses or summer heat gains. Available in 3 sizes, the Sunscope has no moving parts and is fully maintenance-free. The system was designed for use in commercial and residential applications. 7 figs.

  14. Upper gastrointestinal alterations in kidney transplant candidates.

    Science.gov (United States)

    Homse Netto, João Pedro; Pinheiro, João Pedro Sant'Anna; Ferrari, Mariana Lopes; Soares, Mirella Tizziani; Silveira, Rogério Augusto Gomes; Maioli, Mariana Espiga; Delfino, Vinicius Daher Alvares

    2018-05-14

    The incidence of gastrointestinal disorders among patients with chronic kidney disease (CKD) is high, despite the lack of a good correlation between endoscopic findings and symptoms. Many services thus perform upper gastrointestinal (UGI) endoscopy on kidney transplant candidates. This study aims to describe the alterations seen on the upper endoscopies of 96 kidney-transplant candidates seen from 2014 to 2015. Ninety-six CKD patients underwent upper endoscopic examination as part of the preparation to receive kidney grafts. The data collected from the patients' medical records were charted on Microsoft Office Excel 2016 and presented descriptively. Mean values, medians, interquartile ranges and 95% confidence intervals of the clinic and epidemiological variables were calculated. Possible associations between endoscopic findings and infection by H. pylori were studied. Males accounted for 54.17% of the 96 patients included in the study. Median age and time on dialysis were 50 years and 50 months, respectively. The most frequent upper endoscopy finding was enanthematous pangastritis (57.30%), followed by erosive esophagitis (30.20%). Gastric intestinal metaplasia and peptic ulcer were found in 8.33% and 7.30% of the patients, respectively. H. pylori tests were positive in 49 patients, and H. pylori infection was correlated only with non-erosive esophagitis (P = 0.046). Abnormal upper endoscopy findings were detected in all studied patients. This study suggested that upper endoscopy is a valid procedure for kidney transplant candidates. However, prospective studies are needed to shed more light on this matter.

  15. HYBRID ALARM SYSTEMS: COMBINING SPATIAL ALARMS AND ALARM LISTS FOR OPTIMIZED CONTROL ROOM OPERATION

    Energy Technology Data Exchange (ETDEWEB)

    Ronald L. Boring; J.J. Persensky

    2012-07-01

    The US Department of Energy (DOE) is sponsoring research, development, and deployment on Light Water Reactor Sustainability (LWRS), in which the Idaho National Laboratory (INL) is working closely with nuclear utilities to develop technologies and solutions to help ensure the safe operational life extension of current nuclear power plants. One of the main areas of focus is control room modernization. Within control room modernization, alarm system upgrades present opportunities to meet the broader goals of the LWRS project in demonstrating the use and safety of the advanced instrumentation and control (I&C) technologies and the short-term and longer term objectives of the plant. In this paper, we review approaches for and human factors issues behind upgrading alarms in the main control room of nuclear power plants.

  16. Photoexcited Individual Nanowires: Key Elements in Room Temperature Detection of Oxidizing Gases

    International Nuclear Information System (INIS)

    Prades, J. D.; Jimenez-Diaz, R.; Manzanares, M.; Andreu, T.; Cirera, A.; Romano-Rodriguez, A.; Hernandez-Ramirez, F.; Morante, J. R.

    2009-01-01

    Illuminating metal oxide semiconductors with ultra-violet light is a feasible alternative to activate chemical reactions at their surface and thus, using them as gas sensors without the necessity of heating them. Here, the response at room temperature of individual single-crystalline SnO 2 nanowires towards NO 2 is studied in detail. The results reveal that similar responses to those obtained with thermally activated sensors can be achieved by choosing the optimal illumination conditions. This finding paves the way to the development of conductometric gas sensors operated at room temperature. The power consumption in these devices is in range with conventional micromachined sensors.

  17. CEBAF Control Room Renovation

    International Nuclear Information System (INIS)

    Michael Spata; Anthony Cuffe; Thomas Oren

    2005-01-01

    The Machine Control Center (MCC) at Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) was constructed in the early 1990s and based on proven technology of that era. Through our experience over the last 15 years and in our planning for the facilities 12 GeV upgrade we reevaluated the control room environment to capitalize on emerging visualization and display technologies and improve on work-flow processes and ergonomic attributes. The renovation was performed in two phases during the summer of 2004, with one phase occurring during machine operations and the latter, more extensive phase, occurring during our semi-annual shutdown period. The new facility takes advantage of advances in display technology, analog and video signal management, server technology, ergonomic workspace design, lighting engineering, acoustic ceilings and raised flooring solutions to provide a marked improvement in the overall environment of machine operations

  18. Children's preferences concerning ambiance of dental waiting rooms.

    Science.gov (United States)

    Panda, A; Garg, I; Shah, M

    2015-02-01

    Despite many advances in paediatric dentistry, the greatest challenge for any paediatric dentist is to remove the anxiety related to a dental visit and have a child patient to accept dental treatment readily. Minor changes made in the waiting room design can have a major effect on the way any child perceives the upcoming dental experience. This study was carried out to determine children's preferences regarding the dental waiting area so as to improve their waiting experience and reduce their preoperative anxiety before a dental appointment. This was a cross-sectional descriptive study using survey methodology. A questionnaire designed to evaluate children's preferences regarding the waiting room was distributed to new paediatric patients, aged between 6 and 11 years of age, attending an outpatient dental facility and was completed by 212 children (127 males, 85 females). The analyses were carried out on cross-tables using Phi (for 2×2 tables) or Cramer's V (for larger than 2×2 tables) to assess responses to the questionnaire items across age groups and gender. A majority of children preferred music and the ability to play in a waiting room. They also preferred natural light and walls with pictures. They preferred looking at an aquarium or a television and sitting on beanbags and chairs and also preferred plants and oral hygiene posters Repetious. The results obtained from this study may help the dental team decide on an appropriate design of their paediatric waiting room so as to make children comfortable in the dental environment and improve delivery of health care.

  19. Laser light scattering basic principles and practice

    CERN Document Server

    Chu, Benjamin

    1994-01-01

    Geared toward upper-level undergraduate and graduate students, this text introduces the interdisciplinary area of laser light scattering, focusing chiefly on theoretical concepts of quasielastic laser scattering.

  20. Spanish Government delegation in the ISR workshop clean room

    CERN Multimedia

    CERN PhotoLab

    1982-01-01

    A Spanish Government delegation visited CERN before Spain rejoined CERN as a Member State(in 1983). Some delegates were particularly interested in advanced technologies. The picture shows them in the ISR workshop clean room looking at components of vacuum chambers for experiments. From left to right: a delegate, Director-General Herwig Schopper demonstrating the lightness of a titanium chamber, another delegate, the Spanish Minister of Industry and Energy Mr.Ignacio Bayon Marine and Romeo Perin. See also 8202369.

  1. Degradation of quinoline and isoquinoline by vacuum ultraviolet light and mechanism thereof

    International Nuclear Information System (INIS)

    Zhu Dazhang; Ni Yaming; Sun Dongmei; Wang Shilong; Sun Xiaoyu; Yao Side

    2010-01-01

    Since the wavelength is shorter than 190 nm, vacuum ultraviolet light has high energy enough to break the H-O bonds of water to produce HO·, as well as the protection is very easy, degradation of organic contaminants in water by vacuum ultraviolet light has obviously excellent feature of no reagent adding to the wastewater among advanced oxidation technologies. In this paper, it was reported that quinoline and isoquinoline were degraded in water by the irradiation of low-pressure quartz mercury light with the electric power of 200 W which mainly emitted the light of 185 nm and 254 nm. The change regulation of the concentration of substrates, chemical oxygen demand (COD) and total organic carbon (TOC) were investigated as well as the degradation processes of quinoline and isoquinoline were compared. It showed that both quinoline and isoquinoline could be degraded very fast under the given conditions. The concentration of the substrates decreased to nearly 0 in 10 minutes while the apparent first reaction rate constants were 0.41 ± 0.02 min -1 and 0.19 ± 0.01 min -1 , respectively. Meanwhile, the COD and TOC decreased to nearly 0 in 30 minutes. Quinoline has the faster degradation rate. In order to investigate mechanism thereof, pulse radiolysis and laser flash photolysis of quinoline and isoquinoline aqueous solution were performed, respectively. Pulse radiolysis indicated that the reaction rate constant of quinoline and HO· was faster than that of isoquinoline. In the meanwhile, laser flash photolysis indicated that both quinoline and isoquinoline could be ionized by the UV-C light while the photo-ionization efficiency of quinoline was higher than that of quinoline. These two reasons caused the faster degradation rate of quinoline. (authors)

  2. Photodegradation of multiclass fungicides in the aquatic environment and determination by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Celeiro, Maria; Facorro, Rocio; Dagnac, Thierry; Vilar, Vítor J P; Llompart, Maria

    2017-08-01

    The photodegradation behaviour for nine widespread fungicides (benalaxyl, cyprodinil, dimethomorph, fenhexamide, iprovalicarb, kresoxim-methyl, metalaxyl, myclobutanil and tebuconazole) was evaluated in different types of water. Two different systems, direct UV photolysis and UVC/H 2 O 2 advanced oxidation process (AOP), were applied for the photodegradation tests. For the monitoring of the target compound degradation, a method based on direct injection liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. Several fungicide photodegradation by-products were tentatively identified by high-resolution mass spectrometry (HRMS) as well. For the photolysis studies, the efficiency of different types of radiation, UVC (λ = 254 nm) and UVA (λ = 365 nm), was compared. UVC photolysis provided the highest removal with a complete degradation for fenhexamide and kresoxim-methyl, and percentages between 48 and 78% for the other compounds, excluding iprovalicarb and myclobutanil with removals <35%, after 30 min of irradiation. Besides, the photodegradation tests were performed with different initial concentrations of fungicides, and the efficiency of two photoreactor systems was compared. In all cases, the kinetics followed pseudo-first order, and the half-life times could also be calculated. The addition of H 2 O 2 under UVC light allowed an improvement of the reaction kinetics, especially for the most recalcitrant fungicides, obtaining in all cases removals higher than 82% in less than 6 min. Finally, in order to evaluate the suitability of the proposed systems, both UVC photolysis and UVC/H 2 O 2 system were tested in different real water matrices (wastewater, tap water, swimming pool water and river water), showing that the UVC/H 2 O 2 system had the highest removal efficiency in less than 6 min, for all water samples.

  3. Questions asked concerning energy savings in lighting systems

    International Nuclear Information System (INIS)

    Bernet, J.

    2005-01-01

    This article discusses the question why information on the power consumption of lighting fixtures is not often to be found in articles in lifestyle magazines or in the displays of designer-boutiques. The efficiency of various types of lighting is discussed. In particular, the differences between traditional incandescent bulbs and energy-saving lighting systems are examined from the aesthetical, colour-reproduction and energy-consumption points of view. Further information presented includes details on colour-reproduction indexes and colour temperature. The lighting needs of various types of room are looked at and the influence of the physical form of the lighting fixtures on purchasing decisions is examined

  4. Room temperature triplet state spectroscopy of organic semiconductors.

    Science.gov (United States)

    Reineke, Sebastian; Baldo, Marc A

    2014-01-21

    Organic light-emitting devices and solar cells are devices that create, manipulate, and convert excited states in organic semiconductors. It is crucial to characterize these excited states, or excitons, to optimize device performance in applications like displays and solar energy harvesting. This is complicated if the excited state is a triplet because the electronic transition is 'dark' with a vanishing oscillator strength. As a consequence, triplet state spectroscopy must usually be performed at cryogenic temperatures to reduce competition from non-radiative rates. Here, we control non-radiative rates by engineering a solid-state host matrix containing the target molecule, allowing the observation of phosphorescence at room temperature and alleviating constraints of cryogenic experiments. We test these techniques on a wide range of materials with functionalities spanning multi-exciton generation (singlet exciton fission), organic light emitting device host materials, and thermally activated delayed fluorescence type emitters. Control of non-radiative modes in the matrix surrounding a target molecule may also have broader applications in light-emitting and photovoltaic devices.

  5. Chrysallis public lighting sculpture, NHS, Oswestry

    OpenAIRE

    Panneels, Inge

    2005-01-01

    “Chrysalis” is an interactive lighting sculpture which pulsates as if breathing. The lighting is especially visible at night, when patients can come and use the nearby public room or wander up and down the corridor. The cocoon shape was informed by workshops with patients and staff at the RJAH in Gobowen, Shropshire. As this is an orthopaedic Hospital, most patients are there for long periods of time recovering from severe life changing injuries. The recurrent theme of ‘circle’; of family, fr...

  6. Induction and prevention of micronuclei and chromosomal aberrations in cultured human lymphocytes exposed to the light of halogen tungsten lamps.

    Science.gov (United States)

    D'Agostini, F; Caimo, A; De Filippi, S; De Flora, S

    1999-07-01

    Previous studies have shown that the light emitted by halogen tungsten lamps contains UV radiation in the UV-A, UV-B and UV-C regions, induces mutations and irreparable DNA damage in bacteria, enhances the frequency of micronuclei in cultured human lymphocytes and is potently carcinogenic to the skin of hairless mice. The present study showed that the light emitted by an uncovered, traditional halogen lamp induces a significant, dose-related and time-related increase not only in micronuclei but also in chromosome-type aberrations, such as breaks, and even more in chromatid-type aberrations, such as isochromatid breaks, exchanges and isochromatid/chromatid interchanges, all including gaps or not, in cultured human lymphocytes. All these genotoxic effects were completely prevented by shielding the same lamp with a silica glass cover, blocking UV radiation. A new model of halogen lamp, having the quartz bulb treated in order to reduce the output of UV radiation, was considerably less genotoxic than the uncovered halogen lamp, yet induction of chromosomal alterations was observed at high illuminance levels.

  7. Excess Diffuse Light Absorption in Upper Mesophyll Limits CO2 Drawdown and Depresses Photosynthesis.

    Science.gov (United States)

    Earles, J Mason; Théroux-Rancourt, Guillaume; Gilbert, Matthew E; McElrone, Andrew J; Brodersen, Craig R

    2017-06-01

    In agricultural and natural systems, diffuse light can enhance plant primary productivity due to deeper penetration into and greater irradiance of the entire canopy. However, for individual sun-grown leaves from three species, photosynthesis is actually less efficient under diffuse compared with direct light. Despite its potential impact on canopy-level productivity, the mechanism for this leaf-level diffuse light photosynthetic depression effect is unknown. Here, we investigate if the spatial distribution of light absorption relative to electron transport capacity in sun- and shade-grown sunflower ( Helianthus annuus ) leaves underlies its previously observed diffuse light photosynthetic depression. Using a new one-dimensional porous medium finite element gas-exchange model parameterized with light absorption profiles, we found that weaker penetration of diffuse versus direct light into the mesophyll of sun-grown sunflower leaves led to a more heterogenous saturation of electron transport capacity and lowered its CO 2 concentration drawdown capacity in the intercellular airspace and chloroplast stroma. This decoupling of light availability from photosynthetic capacity under diffuse light is sufficient to generate an 11% decline in photosynthesis in sun-grown but not shade-grown leaves, primarily because thin shade-grown leaves similarly distribute diffuse and direct light throughout the mesophyll. Finally, we illustrate how diffuse light photosynthetic depression could overcome enhancement in canopies with low light extinction coefficients and/or leaf area, pointing toward a novel direction for future research. © 2017 American Society of Plant Biologists. All Rights Reserved.

  8. Improving operating room safety

    Directory of Open Access Journals (Sweden)

    Garrett Jill

    2009-11-01

    Full Text Available Abstract Despite the introduction of the Universal Protocol, patient safety in surgery remains a daily challenge in the operating room. This present study describes one community health system's efforts to improve operating room safety through human factors training and ultimately the development of a surgical checklist. Using a combination of formal training, local studies documenting operating room safety issues and peer to peer mentoring we were able to substantially change the culture of our operating room. Our efforts have prepared us for successfully implementing a standardized checklist to improve operating room safety throughout our entire system. Based on these findings we recommend a multimodal approach to improving operating room safety.

  9. Control room philosophy: Principles of control room design and control room work; Kontrollrumsfilosofi: Principer foer kontrollrumsutformning och kontrollrumsarbete

    Energy Technology Data Exchange (ETDEWEB)

    Skriver, Jan; Ramberg, Jasmine; Allwin, Pernilla [Scandpower Risk Management AB, Uppsala (Sweden)

    2006-01-15

    In order to provide insights for improvement of work in control rooms several factors have to be considered. Knowledge of principles including control room philosophies will guide the recommended improvements. In addition to knowledge about specific principles an advantage for an organization can be an understanding of similarities and policies used in other high risk industry. The report has been developed on the basis of a document analysis of international standards and other guiding documents. (NUREG 0711, ISO 11064, ISO 6385, IEC 60964). In addition to the document analysis which has strived to compare the documents to see similarities in important principals, experience from working with control room design, modifications and evaluations in other high risk industries has pervaded the report. Important principles have been identified which are recommended to be included in a control room philosophy. Many of these are similar to the principles identified in the international standards. An additional principal which is regarded as important is the utilization of Key Performance Indicators (KPI) which can be used as a measure to target preventative means. Further more it is critical that the control room philosophy is easy to access and comprehend for all users. One of the challenges that remain after having developed a control room philosophy is how to utilize it in the daily work situation. It is vital that the document remains as a living document, guiding the continual improvement of the control room in the various life cycle stages.

  10. Reliability of estimating the room volume from a single room impulse response

    OpenAIRE

    Kuster, M.

    2008-01-01

    The methods investigated for the room volume estimation are based on geometrical acoustics, eigenmode, and diffuse field models and no data other than the room impulse response are available. The measurements include several receiver positions in a total of 12 rooms of vastly different sizes and acoustic characteristics. The limitations in identifying the pivotal specular reflections of the geometrical acoustics model in measured room impulse responses are examined both theoretically and expe...

  11. Qualities of Inpatient Hospital Rooms: Patients' Perspectives.

    Science.gov (United States)

    Devlin, Ann Sloan; Andrade, Cláudia Campos; Carvalho, Diana

    2016-04-01

    The aim of this qualitative study was to investigate what design features of hospital rooms are valued by inpatients. Little research has explored how patients evaluate the physical environment of their hospital rooms. Most responses are captured by the Hospital Consumer Assessment of Healthcare Providers and Systems survey, which includes only two questions about the physical environment. Two hundred thirty-six orthopedic patients (78 in the United States and 158 in Portugal) listed three features of their hospital room that influenced their level of satisfaction with their hospital stay, indicating whether the feature was positive or negative. The comments were more positive (71.4%) than negative (28.6%). Using the framework of supportive design from Ulrich, over half the comments (64.31%) could be categorized in one of the three dimensions: 33.2% (positive distraction), 22.4% (perceived control), and 6.0% (social support). This total includes Internet (2.7%), which could be categorized as either social support or positive distraction. Comments called "other aspects" focused on overall environmental appraisals, cleanliness, and functionality and maintenance. The majority of comments could be accommodated by Ulrich's theory, but it is noteworthy that other aspects emerge from patients' comments and affect their experience. Cross-cultural differences pointed to the greater role of light and sun for Portuguese patients and health status whiteboard for U.S. Qualitative research can add significantly to our understanding of the healthcare experience and may inform design decisions. © The Author(s) 2015.

  12. Enhanced detection of a low-frequency signal by using broad squeezed light and a bichromatic local oscillator

    Science.gov (United States)

    Li, Wei; Jin, Yuanbin; Yu, Xudong; Zhang, Jing

    2017-08-01

    We experimentally study a protocol of using the broadband high-frequency squeezed vacuum to detect the low-frequency signal. In this scheme, the lower sideband field of the squeezed light carries the low-frequency modulation signal, and the two strong coherent light fields are applied as the bichromatic local oscillator in the homodyne detection to measure the quantum entanglement of the upper and lower sideband for the broadband squeezed light. The power of one of the local oscillators for detecting the upper sideband can be adjusted to optimize the conditional variance in the low-frequency regime by subtracting the photocurrent of the upper sideband field of the squeezed light from that of the lower sideband field. By means of the quantum correlation of the upper and lower sideband for the broadband squeezed light, the low-frequency signal beyond the standard quantum limit is measured. This scheme is appropriate for enhancing the sensitivity of the low-frequency signal by the aid of the broad squeezed light, such as gravitational waves detection, and does not need to directly produce the low-frequency squeezing in an optical parametric process.

  13. Have it your way. A modular approach to custom compact control rooms

    International Nuclear Information System (INIS)

    Harmon, Daryl; Scarola, Ken

    2003-01-01

    In spite of the recent lack of growth in the nuclear power industry, a transition is taking place to compact main control rooms as the design of choice for power generating facilities. This is evident in the design and construction of new facilities, including Advanced Light Water Reactors such as the Korean Shin Kori 3 and 4 units, as well as Generation IV reactors. Also, compact control rooms are increasingly preferred for the modernization of current generation plants. This shift reflects that compact control rooms combine cost savings through equipment reduction and standardization with operability improvements through increased functionality and flexibility and improved presentation. Though compact control rooms feature significantly fewer Human Machine Interface (HMI) devices than their conventional counterparts, customers still require a wide variety of different configurations to accommodate their individual operations philosophies, cultural norms, licensing regulations and physical constraints. To meet this need, Westinghouse Electric Company has developed an innovative, modular approach to designing compact control rooms for nuclear power plants. This approach features a small set of standard HMI devices serving as building blocks for all compact control room functions. The building blocks include qualified and non-safety video devices for implementing displays, alarms, multi-channel soft controls, computerized procedures, etc. These building blocks can be used for (1) large screen overview displays, (2) console-based control and monitoring and (3) HMI devices for conventional, benchboard-style control panels. Their modular design allows these building blocks to be arranged in various physical configurations to meet a wide variety of customer's control room preferences and constraints. For example, a compact control room could use the qualified building blocks (1) to configure a dedicated safety panel independent of the normal operational consoles, or (2

  14. Design and assessment of an anidolic light-duct

    Energy Technology Data Exchange (ETDEWEB)

    Courret, G.; Scartezzini, J.L. [Lab. d`Energie Solaire et de Physique du Batiment (LESO-PB), Ecole Polytechnique Federale de Lausanne (Switzerland); Francioli, D.; Meyer, J.J. [Lab. d`Ergonomie de la Vision (LEV), Inst. Univ. Romand de Sante au Travail, Lausanne (Switzerland)

    1998-08-01

    The system presented here, called Anidolic Ceiling, was developed to show the viability of intensive use of daylight by overcast outdoor conditions in nonresidential buildings. This device consists of a light-duct that is integrated in a suspended ceiling and leads midway into the office. Anidolic (nonimaging optics) elements are placed on either end of the duct, on the outside to collect light rays from the sky and on the inside to control the direction of the emitted light. The present paper describes the system design, as well as an experimental assessment of its daylighting performance in a comparison of a prototype and a full-size conventional facade, for a 6.6-m deep room. Measurements by overcast sky have established that the daylight factor on the work plane 5 m from the window is more than doubled. In addition, a monitoring campaign has shown that 30% of the energy for lighting can be saved. The system was also assessed with regard to the user. Visual comfort measurements (Laboratoire d`Ergonomie de la Vision`s (LEV) method) were carried out showing that for both clear and overcast outdoor conditions, the visual environment quality is objectively improved at the rear working place. Furthermore, 33 people tested both rooms one after the other. They were submitted to a series of visual acuity tests on printed paper and on a computer screen and had to fill in a questionnaire. A comparative study showed that the personal appreciation of the luminous environment is better in the room with an Anidolic Ceiling, with a significant reduction of reading errors both on paper and on the screen. (orig.)

  15. What Orthopaedic Operating Room Surfaces Are Contaminated With Bioburden? A Study Using the ATP Bioluminescence Assay.

    Science.gov (United States)

    Richard, Raveesh Daniel; Bowen, Thomas R

    2017-07-01

    Contaminated operating room surfaces can increase the risk of orthopaedic infections, particularly after procedures in which hardware implantation and instrumentation are used. The question arises as to how surgeons can measure surface cleanliness to detect increased levels of bioburden. This study aims to highlight the utility of adenosine triphosphate (ATP) bioluminescence technology as a novel technique in detecting the degree of contamination within the sterile operating room environment. What orthopaedic operating room surfaces are contaminated with bioburden? When energy is required for cellular work, ATP breaks down into adenosine biphosphate (ADP) and phosphate (P) and in that process releases energy. This process is inherent to all living things and can be detected as light emission with the use of bioluminescence assays. On a given day, six different orthopaedic surgery operating rooms (two adult reconstruction, two trauma, two spine) were tested before surgery with an ATP bioluminescence assay kit. All of the cases were considered clean surgery without infection, and this included the previously performed cases in each sampled room. These rooms had been cleaned and prepped for surgery but the patients had not been physically brought into the room. A total of 13 different surfaces were sampled once in each room: the operating room (OR) preparation table (both pre- and postdraping), OR light handles, Bovie machine buttons, supply closet countertops, the inside of the Bair Hugger™ hose, Bair Hugger™ buttons, right side of the OR table headboard, tourniquet machine buttons, the Clark-socket attachment, and patient positioners used for total hip and spine positioning. The relative light units (RLUs) obtained from each sample were recorded and data were compiled and averaged for analysis. These values were compared with previously published ATP benchmark values of 250 to 500 RLUs to define cleanliness in both the hospital and restaurant industries. All

  16. Fabrication and structural properties of AlN submicron periodic lateral polar structures and waveguides for UV-C applications

    Energy Technology Data Exchange (ETDEWEB)

    Alden, D. [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin (Germany); Guo, W.; Kaess, F.; Bryan, I.; Reddy, P.; Hernandez-Balderrama, Luis H.; Franke, A.; Collazo, R.; Sitar, Z. [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Kirste, R.; Mita, S. [Adroit Materials, Inc., 2054 Kildaire Farm Rd., Suite 205, Cary, North Carolina 27518 (United States); Troha, T.; Zgonik, M. [Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana (Slovenia); Bagal, A.; Chang, C.-H. [Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Hoffmann, A. [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin (Germany)

    2016-06-27

    Periodically poled AlN thin films with submicron domain widths were fabricated for nonlinear applications in the UV-VIS region. A procedure utilizing metalorganic chemical vapor deposition growth of AlN in combination with laser interference lithography was developed for making a nanoscale lateral polarity structure (LPS) with domain size down to 600 nm. The Al-polar and N-polar domains were identified by wet etching the periodic LPS in a potassium hydroxide solution and subsequent scanning electron microscopy (SEM) characterization. Fully coalesced and well-defined vertical interfaces between the adjacent domains were established by cross-sectional SEM. AlN LPSs were mechanically polished and surface roughness with a root mean square value of ∼10 nm over a 90 μm × 90 μm area was achieved. 3.8 μm wide and 650 nm thick AlN LPS waveguides were fabricated. The achieved domain sizes, surface roughness, and waveguides are suitable for second harmonic generation in the UVC spectrum.

  17. Light emitting diodes as an alternative ambient illumination source in photolithography environment

    DEFF Research Database (Denmark)

    Corell, Dennis Dan; Ou, Haiyan; Dam-Hansen, Carsten

    2009-01-01

    We explored an alternative light emitting diode (LED) - based solution to replace the existing yellow fluorescent light tubes (YFT) used in photolithography rooms. A no-blue LED lamp was designed and a prototype was fabricated. For both solutions, the spectral power distribution (SPD) was measured......, the colorimetric values were calculated, and a visual comparison using Gretagmacbeth colorcharts was performed. The visual comparison showed that the LED bulb was better to render colors despite a low color rendering index (CRI). Furthermore, the LED bulb was tested in a photolithography room...... and there was no exposure to the photoresist even after 168 hours illumination....

  18. Light aircraft sound transmission studies - Noise reduction model

    Science.gov (United States)

    Atwal, Mahabir S.; Heitman, Karen E.; Crocker, Malcolm J.

    1987-01-01

    Experimental tests conducted on the fuselage of a single-engine Piper Cherokee light aircraft suggest that the cabin interior noise can be reduced by increasing the transmission loss of the dominant sound transmission paths and/or by increasing the cabin interior sound absorption. The validity of using a simple room equation model to predict the cabin interior sound-pressure level for different fuselage and exterior sound field conditions is also presented. The room equation model is based on the sound power flow balance for the cabin space and utilizes the measured transmitted sound intensity data. The room equation model predictions were considered good enough to be used for preliminary acoustical design studies.

  19. An Methodology for Quality Control and Draught Assessment of Room Ventilation Supply Using Laser Light Sheets

    DEFF Research Database (Denmark)

    Hviid, Christian Anker; Petersen, Steffen

    2016-01-01

    A common technique to investigate draught problems in a room is to make spot measurements of air velocity. This might identify where the draught problem is located but it does not necessarily identify the distribution and source of the problem. Usually visual inspections of the location of ventil......A common technique to investigate draught problems in a room is to make spot measurements of air velocity. This might identify where the draught problem is located but it does not necessarily identify the distribution and source of the problem. Usually visual inspections of the location...... image velocimetry software to gain overall flow pattern visualization, if not accurate readings. The latter result indicates that there could be a potential for real-time velocimetry processing by smartphones but the method in general needs further investigation and documentation....

  20. Experimental and numerical study of smoke propagation through a vent separating two mechanically ventilated rooms

    International Nuclear Information System (INIS)

    Audouin, Laurent; Pretrel, Hugues; Vaux, Samuel

    2015-01-01

    The paper presents an experimental and numerical study about smoke propagation through a horizontal opening between two superposed compartments, as can be encountered in nuclear installations, in case of a fire taking place in the lower room. The experimental configuration proposed in this study consists in two rooms mechanically ventilated and connected each other by a horizontal opening. The fire source is simulated by a propane burner located in the lower room. The inlet ventilation duct is located in the lower room and the exhaust ventilation duct is located in the upper room. For such experimental configuration, several flow regimes at the horizontal opening connecting the two rooms can be encountered depending on the fire power, the opening size (diameter, depth) and the ventilation set-up (location of inlet/outlet ducts, flow rate). Indeed, flow at the opening is governed by buoyant forces due to the hot gases produced by the fire, the inertia effect due to the forced ventilation and the momentum effect due to smoke flow nearby the horizontal opening (for instance, ceiling jet or thermal plume from fire). Consequently, such complex mixed (natural/ forced) convective flows are still a challenge for CFD fire codes to make properly calculations of these experimental scenarios. The objective of this paper is to assess the capability of ISIS code (CFD) to simulate the behaviour of smoke propagation inside these two superposed compartments. Results of this study are presented with details (especially, thermal stratification and flow rates through the horizontal vent) and are discussed thoroughly.

  1. Experimental and numerical study of smoke propagation through a vent separating two mechanically ventilated rooms

    Energy Technology Data Exchange (ETDEWEB)

    Audouin, Laurent; Pretrel, Hugues; Vaux, Samuel [Institut de Radioprotection et de Surete Nucleaire (IRSN), Saint Paul Lez Durance (France)

    2015-12-15

    The paper presents an experimental and numerical study about smoke propagation through a horizontal opening between two superposed compartments, as can be encountered in nuclear installations, in case of a fire taking place in the lower room. The experimental configuration proposed in this study consists in two rooms mechanically ventilated and connected each other by a horizontal opening. The fire source is simulated by a propane burner located in the lower room. The inlet ventilation duct is located in the lower room and the exhaust ventilation duct is located in the upper room. For such experimental configuration, several flow regimes at the horizontal opening connecting the two rooms can be encountered depending on the fire power, the opening size (diameter, depth) and the ventilation set-up (location of inlet/outlet ducts, flow rate). Indeed, flow at the opening is governed by buoyant forces due to the hot gases produced by the fire, the inertia effect due to the forced ventilation and the momentum effect due to smoke flow nearby the horizontal opening (for instance, ceiling jet or thermal plume from fire). Consequently, such complex mixed (natural/ forced) convective flows are still a challenge for CFD fire codes to make properly calculations of these experimental scenarios. The objective of this paper is to assess the capability of ISIS code (CFD) to simulate the behaviour of smoke propagation inside these two superposed compartments. Results of this study are presented with details (especially, thermal stratification and flow rates through the horizontal vent) and are discussed thoroughly.

  2. Light-induced defect creation in hydrogenated polymorphous silicon

    International Nuclear Information System (INIS)

    Morigaki, K.; Takeda, K.; Hikita, H.; Roca i Cabarrocas, P.

    2005-01-01

    Light-induced defect creation in hydrogenated polymorphous silicon (pm-Si:H) is investigated from electron spin resonance measurements and is compared with that in hydrogenated amorphous silicon (a-Si:H). Light-induced defect creation occurs at room temperature similarly for both types of films prepared at 250 deg. C. Thermal annealing of light-induced defects is also investigated as a function of temperature. Different behaviours of annealing characteristics for pm-Si:H from those for a-Si:H are observed and discussed. In particular, we observed a decrease of the light-induced defect creation efficiency with repeated light-soaking-annealing cycles and discuss it with respect to the hydrogen bonding in pm-Si:H films

  3. 207-nm UV Light—A Promising Tool for Safe Low-Cost Reduction of Surgical Site Infections. II: In-Vivo Safety Studies

    Science.gov (United States)

    Buonanno, Manuela; Stanislauskas, Milda; Ponnaiya, Brian; Bigelow, Alan W.; Randers-Pehrson, Gerhard; Xu, Yanping; Shuryak, Igor; Smilenov, Lubomir; Owens, David M.; Brenner, David J.

    2016-01-01

    Background UVC light generated by conventional germicidal lamps is a well-established anti-microbial modality, effective against both bacteria and viruses. However, it is a human health hazard, being both carcinogenic and cataractogenic. Earlier studies showed that single-wavelength far-UVC light (207 nm) generated by excimer lamps kills bacteria without apparent harm to human skin tissue in vitro. The biophysical explanation is that, due to its extremely short range in biological material, 207 nm UV light cannot penetrate the human stratum corneum (the outer dead-cell skin layer, thickness 5–20 μm) nor even the cytoplasm of individual human cells. By contrast, 207 nm UV light can penetrate bacteria and viruses because these cells are physically much smaller. Aims To test the biophysically-based hypothesis that 207 nm UV light is not cytotoxic to exposed mammalian skin in vivo. Methods Hairless mice were exposed to a bactericidal UV fluence of 157 mJ/cm2 delivered by a filtered Kr-Br excimer lamp producing monoenergetic 207-nm UV light, or delivered by a conventional 254-nm UV germicidal lamp. Sham irradiations constituted the negative control. Eight relevant cellular and molecular damage endpoints including epidermal hyperplasia, pre-mutagenic UV-associated DNA lesions, skin inflammation, and normal cell proliferation and differentiation were evaluated in mice dorsal skin harvested 48 h after UV exposure. Results While conventional germicidal UV (254 nm) exposure produced significant effects for all the studied skin damage endpoints, the same fluence of 207 nm UV light produced results that were not statistically distinguishable from the zero exposure controls. Conclusions As predicted by biophysical considerations and in agreement with earlier in vitro studies, 207-nm light does not appear to be significantly cytotoxic to mouse skin. These results suggest that excimer-based far-UVC light could potentially be used for its anti-microbial properties, but without

  4. Electrical lighting for improved wellbeing of elderly citizens

    DEFF Research Database (Denmark)

    Markvart, Jakob; Agnes Sander, Birgit; Kessel, Line

    2015-01-01

    Healthy elderly citizens living in their own homes may benefit from having replaced their existing indoor lighting with a lighting being superior in stimulating their circadian rhythm to improve sleep and general wellbeing. This was hypothesised in the presented study. We replaced the existing...... indoor lighting in the main living room of elderly citizens in 20 uniform private houses in a suburb of Copenhagen. In a randomized cross-over design 29 healthy participants over 65 years were exposed over 3 weeks to blue-enriched and 3 weeks to blue-deprived light with similar corneal photopic...... illuminances from 8 am to 13 pm. The two light epochs were separated by one week neutral indoor light. Daylight factors were measured for each of the houses. The pre-experimental lighting conditions were documented by pictures and the experimental light was measured on location using portable photometers...

  5. Data mining application in industrial energy audit for lighting

    Energy Technology Data Exchange (ETDEWEB)

    Maricar, N.M.; Kim, G.C.; Jamal, N. [Kolej Univ., Melaka (Malaysia). Faculty of Electrical Engineering

    2005-07-01

    A data mining application for lighting energy audits at industrial sites was presented. Data collection was based on the parameters needed for the analysis part of the audit. Data collection included the activity for which the room was used; its dimension; light level readings in lux; the number of luminaries; the number of lamps per luminaries; lamp fixtures; and lamp wattage. The lumen method was used to calculate the recommended numbers of luminaries in the room. The number was then compared with the existing system's luminaries. The installed load efficacy ratio (ILER) was then used to determine proper retrofit action to maximize energy usage. The difference between the calculated lux and the standard lux was used to create data subsets. A data mining algorithm was used to determine that the ILER plays an important role in calculating the efficiency of lighting systems. It was also concluded that the method can be used to minimize the time needed to analyze large amounts of lighting data. The results of case studies were also used to show that the combined data mining algorithm provided accurate assessments using existing calculated data. 7 refs., 8 tabs., 5 figs.

  6. The investigation of the light radiation caused polyethylene based materials deterioration by means of atomic force microscopy

    International Nuclear Information System (INIS)

    Sikora, A; Moroń, L; Wałecki, M; Kryla, P; Grabarek, A

    2016-01-01

    The impact of the environmental conditions on the materials used in various devices and constructions, in particular in electrotechnical applications, has an critical impact in terms of their reliability and utilization range in specific climatic conditions. Due to increasing utilitarian requirements, technological processes complexity and introducing new materials (for instance nanomaterials), advanced diagnostic techniques are desired. One of such techniques is atomic force microscopy (AFM), which allows to study the changes of the roughness and mechanical properties of the surface at the submicrometer scale, enabling the investigation of the degradation processes. In this work the deterioration of selected group of polyethylene based materials have been measured by means of AFM, as the samples were exposed to the simulated solar light and UV-C radiation. Such an analysis of the environmental conditions impact on the deterioration process using AFM methods for various versions of specific material was not presented before. (paper)

  7. Future control room design (modernization of control room systems)

    International Nuclear Information System (INIS)

    Reischl, Ludwig; Freitag, Timo; Dergel, Rene

    2009-01-01

    In the frame of lifetime extension for nuclear power plants the modernization of the complete safety and operational control technology will be digitalized. It is also recommended to modernize the operator facilities, monitoring systems in the control room, the back-up shut-down center and the local control stations. The authors summarize the reasons for the modernization recommendations and discuss possible solutions for display-oriented control rooms. A concept for control room backfitting includes generic requirements, requirements of the local authorities, ergonomic principles information content and information density, and the design process. The backfitting strategy should include a cooperation with the operational personnel, The quality assurance and training via simulator needs sufficient timing during the implementation of the backfitting.

  8. [Difference in photoperiodic sensitivity of the upper and lower side of leaves of Kalanchoe blossfeldiana].

    Science.gov (United States)

    Bünning, E; Moser, I

    1966-09-01

    The short-day plant Kalanchoe blossfeldiana was grown on short photoperiods and was given supplementary light of low intensity (4-7 lux). If the supplementary light was supplied to the upper sides of the leaves flowering was strongly inhibited. Irradiation of the lower sides was much less effective.

  9. Room temperature nanoindentation creep of hot-pressed B6O

    CSIR Research Space (South Africa)

    Machaka, R

    2014-06-01

    Full Text Available of the nanoindentation creep behavior in B6O ceramics. 1 Room temperature nanoindentation creep of hot-pressed B6O Ronald Machakaa,b,* , Trevor E. Derryb,d, Iakovos Sigalasb,c aLight Metals, Materials Science and Manufacturing, Council for Scientific..., University of the Witwatersrand, Private Bag 3, Wits, Johannesburg 2050, South Africa dSchool of Physics, University of the Witwatersrand, Private Bag 3, Wits, Johannesburg 2050, 2050 South Africa Abstract: Nanoindentation has become a widely...

  10. Consequences of modern information display technologies in power plant control rooms. What has changed in control rooms?

    International Nuclear Information System (INIS)

    Kruip, Jochen

    2007-01-01

    Control rooms of power plants have undergone major developments and changes, some of them considerable, over the past few years. The most visible change has been the display of information on a variety of video screens and projectors. The question examined in the article is whether the visible or invisible changes in power plant control rooms have any influence on the training of operators. In a contribution coming from the Simulator Center, this question naturally focuses on simulator training, which is to be discussed in the light of the basic objectives of this type of training. The main duty of the Essen Simulator Center is to offer first training and in-career training to the licensed operators of nuclear power plants. The experience accumulated in nearly thirty years of simulator training has been laid down in the 'Kompendium der Simulatorschulung' (Handbook of Simulator Training). Simulator training, as referred to above, is a major component of all training programs. The two main objectives of simulator training are 'reliability in operation' and 'experience' in handling the new information systems and digital I and C systems. In the future, simulators can also be used for advanced developments and for advance testing and training. (orig.)

  11. Controlling the clean room atmosphere

    International Nuclear Information System (INIS)

    Meeks, R.F.

    1979-01-01

    Several types of clean rooms are commonly in use. They include the conventional clean room, the horizontal laminar flow clean room, the vertical laminar flow clean room and a fourth type that incorporates ideas from the previous types and is known as a clean air bench or hood. These clean rooms are briefly described. The origin of contamination and methods for controlling the contamination are discussed

  12. Phase advancing human circadian rhythms with morning bright light, afternoon melatonin, and gradually shifted sleep: can we reduce morning bright-light duration?

    Science.gov (United States)

    Crowley, Stephanie J; Eastman, Charmane I

    2015-02-01

    Efficient treatments to phase-advance human circadian rhythms are needed to attenuate circadian misalignment and the associated negative health outcomes that accompany early-morning shift work, early school start times, jet lag, and delayed sleep phase disorder. This study compared three morning bright-light exposure patterns from a single light box (to mimic home treatment) in combination with afternoon melatonin. Fifty adults (27 males) aged 25.9 ± 5.1 years participated. Sleep/dark was advanced 1 h/day for three treatment days. Participants took 0.5 mg of melatonin 5 h before the baseline bedtime on treatment day 1, and an hour earlier each treatment day. They were exposed to one of three bright-light (~5000 lux) patterns upon waking each morning: four 30-min exposures separated by 30 min of room light (2-h group), four 15-min exposures separated by 45 min of room light (1-h group), and one 30-min exposure (0.5-h group). Dim-light melatonin onsets (DLMOs) before and after treatment determined the phase advance. Compared to the 2-h group (phase shift = 2.4 ± 0.8 h), smaller phase-advance shifts were seen in the 1-h (1.7 ± 0.7 h) and 0.5-h (1.8 ± 0.8 h) groups. The 2-h pattern produced the largest phase advance; however, the single 30-min bright-light exposure was as effective as 1 h of bright light spread over 3.25 h, and it produced 75% of the phase shift observed with 2 h of bright light. A 30-min morning bright-light exposure with afternoon melatonin is an efficient treatment to phase-advance human circadian rhythms. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Phase advancing human circadian rhythms with morning bright light, afternoon melatonin, and gradually shifted sleep: can we reduce morning bright light duration?

    Science.gov (United States)

    Crowley, Stephanie J.; Eastman, Charmane I.

    2015-01-01

    OBJECTIVE Efficient treatments to phase advance human circadian rhythms are needed to attenuate circadian misalignment and the associated negative health outcomes that accompany early morning shift work, early school start times, jet lag, and delayed sleep phase disorder. This study compared three morning bright light exposure patterns from a single light box (to mimic home treatment) in combination with afternoon melatonin. METHODS Fifty adults (27 males) aged 25.9±5.1 years participated. Sleep/dark was advanced 1 hour/day for 3 treatment days. Participants took 0.5 mg melatonin 5 hours before baseline bedtime on treatment day 1, and an hour earlier each treatment day. They were exposed to one of three bright light (~5000 lux) patterns upon waking each morning: four 30-minute exposures separated by 30 minutes of room light (2 h group); four 15-minute exposures separated by 45 minutes of room light (1 h group), and one 30-minute exposure (0.5 h group). Dim light melatonin onsets (DLMOs) before and after treatment determined the phase advance. RESULTS Compared to the 2 h group (phase shift=2.4±0.8 h), smaller phase advance shifts were seen in the 1 h (1.7±0.7 h) and 0.5 h (1.8±0.8 h) groups. The 2-hour pattern produced the largest phase advance; however, the single 30-minute bright light exposure was as effective as 1 hour of bright light spread over 3.25 h, and produced 75% of the phase shift observed with 2 hours of bright light. CONCLUSIONS A 30-minute morning bright light exposure with afternoon melatonin is an efficient treatment to phase advance human circadian rhythms. PMID:25620199

  14. Can Lighting Influence Self-Disclosure?

    Science.gov (United States)

    Mehta, Veli; Mukherjee, Sumitava; Manjaly, Jaison A

    2017-01-01

    With the advent of social networks where people disclose a lot of their information and opinions publicly, this research attempted to re-look at the effect of environmental lighting on willingness and actual disclosure of personal information. Previous literatures mostly addressed counseling setups and the findings were mixed. In order to clarify the effect of lighting on self-disclosure, two experiments were conducted with reported willingness to disclose (Experiment 1) as well as actual disclosure (Experiment 2) on a range of topics like social issues, body, money, work, and personality. While quite a handful of studies have reported differences in disclosure from very subtle environmental lighting manipulations, in both experiments we could not find any effect of ambient room lighting conditions on self-disclosure. These results call for caution both in over-interpreting subtle environmental effects and in increased generalization of perceptual metaphors to actual behavior.

  15. The Effect of Photon Source on Heterogeneous Photocatalytic Oxidation of Ethanol by a Silica-Titania Composite

    Science.gov (United States)

    Coutts, Janelle L.; Levine, Lanfang H.; Richards, Jeffrey T.; Mazyck, David W.

    2011-01-01

    The objective of this study was to distinguish the effect of photon flux (i.e., photons per unit time reaching a surface) from that of photon energy (i.e., wavelength) of a photon source on the silica-titania composite (STC)-catalyzed degradation of ethanol in the gas phase. Experiments were conducted in a bench-scale annular reactor packed with STC pellets and irradiated with either a UV-A fluorescent black light blue lamp ((gamma)max=365 nm) at its maximum light intensity or a UV-C germicidal lamp ((gamma)max=254 nm) at three levels of light intensity. The STC-catalyzed oxidation of ethanol was found to follow zero-order kinetics with respect to CO2 production, regardless of the photon source. Increased photon flux led to increased EtOH removal, mineralization, and oxidation rate accompanied by lower intermediate concentration in the effluent. The oxidation rate was higher in the reactor irradiated by UV-C than by UV-A (38.4 vs. 31.9 nM/s) at the same photon flux, with similar trends for mineralization (53.9 vs. 43.4%) and reaction quantum efficiency (i.e., photonic efficiency, 63.3 vs. 50.1 nmol CO2 (mu)mol/photons). UV-C irradiation also led to decreased intermediate concentration in the effluent . compared to UV-A irradiation. These results demonstrated that STC-catalyzed oxidation is enhanced by both increased photon flux and photon energy.

  16. Novel room temperature ferromagnetic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Amita [KTH Royal Inst. of Technology, Stockholm (Sweden)

    2004-06-01

    Today's information world, bits of data are processed by semiconductor chips, and stored in the magnetic disk drives. But tomorrow's information technology may see magnetism (spin) and semiconductivity (charge) combined in one 'spintronic' device that exploits both charge and 'spin' to carry data (the best of two worlds). Spintronic devices such as spin valve transistors, spin light emitting diodes, non-volatile memory, logic devices, optical isolators and ultra-fast optical switches are some of the areas of interest for introducing the ferromagnetic properties at room temperature in a semiconductor to make it multifunctional. The potential advantages of such spintronic devices will be higher speed, greater efficiency, and better stability at a reduced power consumption. This Thesis contains two main topics: In-depth understanding of magnetism in Mn doped ZnO, and our search and identification of at least six new above room temperature ferromagnetic semiconductors. Both complex doped ZnO based new materials, as well as a number of nonoxides like phosphides, and sulfides suitably doped with Mn or Cu are shown to give rise to ferromagnetism above room temperature. Some of the highlights of this work are discovery of room temperature ferromagnetism in: (1) ZnO:Mn (paper in Nature Materials, Oct issue, 2003); (2) ZnO doped with Cu (containing no magnetic elements in it); (3) GaP doped with Cu (again containing no magnetic elements in it); (4) Enhancement of Magnetization by Cu co-doping in ZnO:Mn; (5) CdS doped with Mn, and a few others not reported in this thesis. We discuss in detail the first observation of ferromagnetism above room temperature in the form of powder, bulk pellets, in 2-3 mu-m thick transparent pulsed laser deposited films of the Mn (<4 at. percent) doped ZnO. High-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS) spectra recorded from 2 to 200nm areas showed homogeneous

  17. A Pilot Study Investigating the Effects of Advanced Nuclear Power Plant Control Room Technologies: Methods and Qualitative Results

    Energy Technology Data Exchange (ETDEWEB)

    BLanc, Katya Le [Idaho National Lab. (INL), Idaho Falls, ID (United States); Powers, David [Idaho National Lab. (INL), Idaho Falls, ID (United States); Joe, Jeffrey [Idaho National Lab. (INL), Idaho Falls, ID (United States); Spielman, Zachary [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Brandon [Idaho National Lab. (INL), Idaho Falls, ID (United States); Fitzgerald, Kirk [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-08-01

    Control room modernization is an important part of life extension for the existing light water reactor fleet. None of the 99 currently operating commercial nuclear power plants in the U.S. has completed a full-scale control room modernization to date. Nuclear power plant main control rooms for the existing commercial reactor fleet remain significantly analog, with only limited digital modernizations. Upgrades in the U.S. do not achieve the full potential of newer technologies that might otherwise enhance plant and operator performance. The goal of the control room upgrade benefits research is to identify previously overlooked benefits of modernization, identify candidate technologies that may facilitate such benefits, and demonstrate these technologies through human factors research. This report describes a pilot study to test upgrades to the Human Systems Simulation Laboratory at INL.

  18. PROPOSAL OF A CLINICAL CARE PATHWAY FOR THE MANAGEMENT OF ACUTE UPPER GASTROINTESTINAL BLEEDING.

    Science.gov (United States)

    Franco, Matheus Cavalcante; Nakao, Frank Shigueo; Rodrigues, Rodrigo; Maluf-Filho, Fauze; Paulo, Gustavo Andrade de; Libera, Ermelindo Della

    2015-12-01

    Upper gastrointestinal bleeding implies significant clinical and economic repercussions. The correct establishment of the latest therapies for the upper gastrointestinal bleeding is associated with reduced in-hospital mortality. The use of clinical pathways for the upper gastrointestinal bleeding is associated with shorter hospital stay and lower hospital costs. The primary objective is the development of a clinical care pathway for the management of patients with upper gastrointestinal bleeding, to be used in tertiary hospital. It was conducted an extensive literature review on the management of upper gastrointestinal bleeding, contained in the primary and secondary information sources. The result is a clinical care pathway for the upper gastrointestinal bleeding in patients with evidence of recent bleeding, diagnosed by melena or hematemesis in the last 12 hours, who are admitted in the emergency rooms and intensive care units of tertiary hospitals. In this compact and understandable pathway, it is well demonstrated the management since the admission, with definition of the inclusion and exclusion criteria, passing through the initial clinical treatment, posterior guidance for endoscopic therapy, and referral to rescue therapies in cases of persistent or rebleeding. It was also included the care that must be taken before hospital discharge for all patients who recover from an episode of bleeding. The introduction of a clinical care pathway for patients with upper gastrointestinal bleeding may contribute to standardization of medical practices, decrease in waiting time for medications and services, length of hospital stay and costs.

  19. Influence of staircase ventilation state on the airflow and heat transfer of the heated room on the middle floor of high rise building

    International Nuclear Information System (INIS)

    Shi, W.X.; Ji, J.; Sun, J.H.; Lo, S.M.; Li, L.J.; Yuan, X.Y.

    2014-01-01

    Highlights: • Experiments are conducted in a scaled building model. • The flow and heat transfer in the heated room are investigated. • The staircase ventilation state influence on the heated room. • The results are useful to understand the safety and energy efficiency of building. - Abstract: Safety and energy efficiency of high rise buildings have attracted public attention in recent decades. In this paper, a set of experiments was conducted in a scaled building model with 12 floors to study the influence of the staircase ventilation state on the flow and heat transfer of the heated room on the middle floor. The airflow, room temperature and fuel burning rate were investigated. It is found that when the window above the heated room is opened, the vents state below the heated room has a significant effect on the airflow and heat transfer in the heated room. When the vents below the heated room are closed, the single-directional air flows into the heated room owing to the stronger stack effect. And the flame tilt angle is larger and the upper hot smoke temperature in the heated room is low. However, when the windows above the heated room are closed, the vents state below the heated room has little influence on the airflow and heat transfer in the heated room. And, there is two-directional air flowing through the door of the heated room The burning rate of heat source is also affected by the staircase ventilation state, and the variation trend varies with the opened window position and pool size

  20. Nucleotide excision repair genes are expressed at low levels and are not detectably inducible in Caenorhabditis elegans somatic tissues, but their function is required for normal adult life after UVC exposure

    International Nuclear Information System (INIS)

    Boyd, Windy A.; Crocker, Tracey L.; Rodriguez, Ana M.; Leung, Maxwell C.K.; Wade Lehmann, D.; Freedman, Jonathan H.; Van Houten, Ben; Meyer, Joel N.

    2010-01-01

    We performed experiments to characterize the inducibility of nucleotide excision repair (NER) in Caenorhabditis elegans, and to examine global gene expression in NER-deficient and -proficient strains as well as germline vs. somatic tissues, with and without genotoxic stress. We also carried out experiments to elucidate the importance of NER in the adult life of C. elegans under genotoxin-stressed and control conditions. Adult lifespan was not detectably different between wild-type and NER-deficient xpa-1 nematodes under control conditions. However, exposure to 6 J/m 2 /day of ultraviolet C radiation (UVC) decreased lifespan in xpa-1 nematodes more than a dose of 100 J/m 2 /day in wild-type. Similar differential sensitivities were observed for adult size and feeding. Remarkably, global gene expression was nearly identical in young adult wild-type and xpa-1 nematodes, both in control conditions and 3 h after exposure to 50 J/m 2 UVC. Neither NER genes nor repair activity were detectably inducible in young adults that lacked germ cells and developing embryos (glp-1 strain). However, expression levels of dozens of NER and other DNA damage response genes were much (5-30-fold) lower in adults lacking germ cells and developing embryos, suggesting that somatic and post-mitotic cells have a much lower DNA repair ability. Finally, we describe a refinement of our DNA damage assay that allows damage measurement in single nematodes.

  1. Nucleotide excision repair genes are expressed at low levels and are not detectably inducible in Caenorhabditis elegans somatic tissues, but their function is required for normal adult life after UVC exposure

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, Windy A. [Biomolecular Screening Branch, National Toxicology Program, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC (United States); Crocker, Tracey L. [Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States); Rodriguez, Ana M. [Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC (United States); Leung, Maxwell C.K. [Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States); Wade Lehmann, D. [Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC (United States); Freedman, Jonathan H. [Laboratory of Molecular Toxicology, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC (United States); Van Houten, Ben [Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC (United States); Meyer, Joel N., E-mail: joel.meyer@duke.edu [Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States)

    2010-01-05

    We performed experiments to characterize the inducibility of nucleotide excision repair (NER) in Caenorhabditis elegans, and to examine global gene expression in NER-deficient and -proficient strains as well as germline vs. somatic tissues, with and without genotoxic stress. We also carried out experiments to elucidate the importance of NER in the adult life of C. elegans under genotoxin-stressed and control conditions. Adult lifespan was not detectably different between wild-type and NER-deficient xpa-1 nematodes under control conditions. However, exposure to 6 J/m{sup 2}/day of ultraviolet C radiation (UVC) decreased lifespan in xpa-1 nematodes more than a dose of 100 J/m{sup 2}/day in wild-type. Similar differential sensitivities were observed for adult size and feeding. Remarkably, global gene expression was nearly identical in young adult wild-type and xpa-1 nematodes, both in control conditions and 3 h after exposure to 50 J/m{sup 2} UVC. Neither NER genes nor repair activity were detectably inducible in young adults that lacked germ cells and developing embryos (glp-1 strain). However, expression levels of dozens of NER and other DNA damage response genes were much (5-30-fold) lower in adults lacking germ cells and developing embryos, suggesting that somatic and post-mitotic cells have a much lower DNA repair ability. Finally, we describe a refinement of our DNA damage assay that allows damage measurement in single nematodes.

  2. UVC-mutagenesis in acetogens: resistance to methanol, ethanol, acetone, or n-butanol in recombinants with tailored genomes as the step in engineering of commercial biocatalysts for continuous CO₂/H₂ blend fermentations.

    Science.gov (United States)

    Kiriukhin, Michael; Tyurin, Michael; Gak, Eugene

    2014-05-01

    Time- and cost-efficient six-step UVC-mutagenesis was developed and validated to generate acetogen mutants with preliminary reduced genomes to prevent product inhibition in the to-be-engineered commercial biocatalysts. Genome reduction was performed via elimination of pta, ack, spo0A, spo0J and some pro-phage genes. UVC-mutants such as Clostridium sp. MT1784RG, Clostridium sp. MT653RG, Clostridium sp. MT896RG, and Clostridium sp. MT1962RG (all 4 share 97 % DNA homology with Clostridium ljungdahlii ATCC 55383) were selected based on resistance to methanol (3 M), ethanol (3.6 M), acetone (2.5 M), or n-butanol (0.688 M), respectively. As a part of the biocatalyst engineering algorithm, genome reduction step was associated with integration of attTn7 recognition sequence to the chromosomes of each of the above strains to prepare the defined integration sites for future integration of multi-copy synthetic operons encoding biosynthesis of methanol, ethanol, acetone or n-butanol. Reduced genome mutants had cell duplication times decreased compared to the same for the respective parental strains. All groups of mutants had decreased share of palmitic (C16:0) and increased share of oleic (C18:1) acids along with detection of isopropylstearate (C20) compared to the parental strains. Mutants resistant to acetone and n-butanol also had monounsaturated fatty acid (C20:1) not found in parental strains. Cyclopropane fatty acid (C21) was identified only in n-butanol resistant mutants.

  3. Visible and invisible the wonders of light phenomena

    CERN Document Server

    Bisi, Olmes

    2015-01-01

    Light phenomena have intrigued humankind since prehistory. Think of the rainbow, a sunset on the sea, a game of shadows. Humans have always used light for their own needs, from cooking food to illuminating a room. However, light is not only limited to what we can see with our eyes. The invisible part of the electromagnetic spectrum is broad and dynamic. This book outlines the mysteries and wonders of electromagnetism, heat, and light. It also covers the history of our scientific understanding of light. The dark as well as the bright sides of light are fully explored in these pages, from their impact on our world to their use in cutting-edge technologies in a variety of fields. Numerous full-color images and drawings complement the text, and light phenomena are explained in a simple and engaging way.

  4. Upper limb muscle activation during sports video gaming of persons with spinal cord injury.

    Science.gov (United States)

    Jaramillo, Jeffrey P; Johanson, M Elise; Kiratli, B Jenny

    2018-04-04

    Video gaming as a therapeutic tool has largely been studied within the stroke population with some benefits reported in upper limb motor performance, balance, coordination, and cardiovascular status. To date, muscle activation of upper limb muscles in persons with spinal cord injuries (SCI) has not been studied during video game play. In this paper, we provide descriptive and comparative data for muscle activation and strength during gaming for players with tetraplegia and paraplegia, as well as, compare these results with data from traditional arm exercises (ie, biceps curl and shoulder press) with light weights which are commonly prescribed for a home program. Fourteen individuals with chronic SCI (9 tetraplegia, 5 paraplegia). We measured upper limb muscle activation with surface electromyography (EMG) during Wii Sports video game play. Muscle activation was recorded from the playing arm during 4 selected games and normalized to a maximum voluntary contraction (MVC). Heart rate and upper limb motion were recorded simultaneously with EMG. Wilcoxon signed rank tests were used to analyze differences in muscle activation between participants with paraplegia versus tetraplegia and compare gaming with traditional arm exercises with light weights. A Friedman 2-way analysis of variance identified key muscle groups active during game play. Overall muscle activation across the games was not different between those with paraplegia and tetraplegia. Heart rate during video game play for tennis and boxing were on average 10 to 20 beats/minute above resting heart rate. The magnitude of EMG was relatively greater for traditional arm exercises with light weights compared with game play. The selected Wii games were able to elicit upper extremity muscle activation and elevated heart rates for individuals with SCI that may be used to target therapeutic outcomes.

  5. Upper limit for J/psi→γ+ axion

    International Nuclear Information System (INIS)

    Edwards, C.; Partridge, R.; Peck, C.; Porter, F.C.; Antreasyan, D.; Gu, Y.F.; Kollmann, W.; Richardson, M.; Strauch, K.; Weinstein, A.; Aschman, D.; Burnett, T.; Cavalli-Sforza, M.; Coyne, D.; Newman, C.; Sadrozinski, H.F.W.; Gelphman, D.; Hofstadter, R.; Horisberger, R.; Kirkbride, I.; Kolanoski, H.; Koenigsmann, K.; Lee, R.; Liberman, A.; O'Reilly, J.; Osterheld, A.; Pollock, B.; Tompkins, J.; Bloom, E.; Bulos, F.; Chestnut, R.; Gaiser, J.; Godfrey, G.; Kiesling, C.; Lockman, W.; Oreglia, M.; Scharre, D.L.; Wacker, K.

    1982-01-01

    The authors have searched with the crystal ball detector for axionlike particles in radiative J/psi decays. An upper limit on the branching ratio B(J/psi→γ+a) -5 (90% C.L.) is obtained. This result holds for long-lived, noninteracting pseudoscalar or vector particles of mass less than 1 GeV. Thus, this experiment also places stringent limits on the existence of other possible light bosons such as those arising in supersymmetric theories

  6. Bright ideas. Some rules of thumb for interior lighting design and selection.

    Science.gov (United States)

    Hunter, Claudia M

    2002-07-01

    Interior lighting design and selection can be a demanding assignment for a health facilities manager or department head. It requires a balance between conflicting needs, such as providing good task lighting for a nursing station while also shielding luminaires that are visible from patients' rooms to avoid glare.

  7. Control room lay-out

    International Nuclear Information System (INIS)

    Toma, Violeta

    2004-01-01

    TRIUMF (Tri-University Meson Facility) is Canada's national laboratory for particle and nuclear physics. There are 6 accelerators and 3 Control Rooms at TRIUMF. The main control room serves the big cyclotron, the 500 MeV, and the adjacent experiment. The 42 MeV and two 32 MeV ones are production dedicated. These cyclotrons belong to a private company but are operated by TRIUMF staff from ATG (Applied Technology Group) Control Room. The last is ISAC (Isotope Acceleration and Separation) Control Room, from which the LINAC is controlled. Research areas cover theoretical (2 subjects), pure (5 subjects) and applied (8 subjects) physics. In the early '70s, as the 500 MeV was being completed, the first Control Room was built in the main accelerator building. The recent topics covered by this paper are proton and pion therapy, what are the operator's duties?, the CP42, TR30 and TR13 cyclotron control rooms, the ISAC control systems including control room modification. Due to the nature of an operator's job, the Control Room layout is pretty important. This is true for any work environment, but when working shifts it becomes essential. Lots of time and effort, not to mention money, were spent to figure out the optimum configuration. It seems to me that the key factor in the control room layout is versatility, and this is because it has to keep happy a group of people with different inclinations, which have a tendency to become quite moody after the second night shift. No matter what, there will still be unhappy people, but we are trying our best. (Y. Tanaka)

  8. Evolving Our Evaluation of Lighting Environments Project

    Science.gov (United States)

    Terrier, Douglas; Clayton, Ronald; Clark, Toni Anne

    2016-01-01

    Imagine you are an astronaut on their 100th day of your three year exploration mission. During your daily routine to the small hygiene compartment of the spacecraft, you realize that no matter what you do, your body blocks the light from the lamp. You can clearly see your hands or your toes but not both! What were those design engineers thinking! It would have been nice if they could have made the walls glow instead! The reason the designers were not more innovative is that their interpretation of the system lighting requirements didn't allow them to be so! Currently, our interior spacecraft lighting standards and requirements are written around the concept of a quantity of light illuminating a spacecraft surface. The natural interpretation for the engineer is that a lamp that throws light to the surface is required. Because of certification costs, only one lamp is designed and small rooms can wind up with lamps that may be inappropriate for the room architecture. The advances in solid state light emitting technologies and optics for lighting and visual communication necessitates the evaluation of how NASA envisions spacecraft lighting architectures and how NASA uses industry standards for the design and evaluation of lighting system. Current NASA lighting standards and requirements for existing architectures focus on the separate ability of a lighting system to throw light against a surface or the ability of a display system to provide the appropriate visual contrast. Realization that these systems can be integrated is not realized. The result is that the systems are developed independent from one another and potential efficiencies that could be realized from borrowing from the concept of one technology and applying it for the purpose of the other does not occur. This project investigated the possibility of incorporating large luminous surface lamps as an alternative or supplement to overhead lighting. We identified existing industry standards for architectural

  9. Space fireworks for upper atmospheric wind measurements by sounding rocket experiments

    Science.gov (United States)

    Yamamoto, M.

    2016-01-01

    Artificial meteor trains generated by chemical releases by using sounding rockets flown in upper atmosphere were successfully observed by multiple sites on ground and from an aircraft. We have started the rocket experiment campaign since 2007 and call it "Space fireworks" as it illuminates resonance scattering light from the released gas under sunlit/moonlit condition. By using this method, we have acquired a new technique to derive upper atmospheric wind profiles in twilight condition as well as in moonlit night and even in daytime. Magnificent artificial meteor train images with the surrounding physics and dynamics in the upper atmosphere where the meteors usually appear will be introduced by using fruitful results by the "Space firework" sounding rocket experiments in this decade.

  10. Light-dependent magnetoreception: orientation behaviour of migratory birds under dim red light.

    Science.gov (United States)

    Wiltschko, Roswitha; Munro, Ursula; Ford, Hugh; Stapput, Katrin; Wiltschko, Wolfgang

    2008-10-01

    Magnetic compass orientation in migratory birds has been shown to be based on radical pair processes and to require light from the short wavelength part of the spectrum up to 565 nm Green. Under dim red light of 645 nm wavelength and 1 mW m(-2) intensity, Australian silvereyes and European robins showed a westerly tendency that did not change between spring and autumn, identifying it as a 'fixed direction' response. A thorough analysis revealed that this orientation did not involve the inclination compass, but was a response based on the polarity of the magnetic field. Furthermore, in contrast to the orientation under short-wavelength light, it could be disrupted by local anaesthesia of the upper beak where iron-containing receptors are located, indicating that it is controlled by these receptors. The similarity of the response under dim red light to the response in total darkness suggests that the two responses may be identical. These findings indicate that the observed 'fixed direction' response under dim red light is fundamentally different from the normal compass orientation, which is based on radical pair processes.

  11. A naturally light Higgs without light Top Partners

    CERN Document Server

    Carmona, Adrian

    2015-01-01

    We demonstrate that the inclusion of a realistic lepton sector can relax significantly the upper bound on top partner masses in minimal composite Higgs models, induced by the lightness of the Higgs boson. To that extend, we present a comprehensive survey of the impact of different realizations of the fermion sectors on the Higgs potential, with a special emphasis on the role of the leptons. The non-negligible compositeness of the $\\tau_R$ in a general class of models that address the flavor structure of the lepton sector and the smallness of the corresponding FCNCs, can have a significant effect on the potential. We find that, with the $\\tau_R$ in the symmetric representation of $SO(5)$, an increase in the maximally allowed mass of the lightest top partner of $\\gtrsim 1$ TeV is possible for minimal quark setups like the MCHM$_{5,10}$, without increasing the tuning. A light Higgs boson $m_H \\sim(100-200)$ GeV is a natural prediction of such models, which thus provide a new setup that can evade ultra-light top ...

  12. Research on the speed of light transmission in a dual-frequency laser pumped single fiber with two directions

    Science.gov (United States)

    Qiu, Wei; Liu, Jianjun; Wang, Yuda; Yang, Yujing; Gao, Yuan; Lv, Pin; Jiang, Qiuli

    2018-01-01

    In this article a general theory of the coherent population oscillation effect in an erbium-doped fiber at room temperature is presented. We use dual pumping light waves with a simplified two-level system. Thus the time delay equations can be calculated from rate equations and the transmission equation. Using numerical simulation, in the case of dual-frequency pump light waves (1480 nm and 980 nm) with two directions, we analyze the influence of the pump power ratio on the group speed of light propagation. In addition, we compare slow light propagation with a single-pumping light and slow light propagation with a dual-pumping light at room temperature. The discussion shows that a larger time delay of slow light propagation can be obtained with a dual-frequency pumping laser. Compared to previous research methods, a dual-frequency laser pumped fiber with two directions is more controllable. Moreover, we conclude that the group velocity of light can be varied by changing the pump ratio.

  13. Effect of ambient light on the time needed to complete a fetal biophysical profile: A randomized controlled trial.

    Science.gov (United States)

    Said, Heather M; Gupta, Shweta; Vricella, Laura K; Wand, Katy; Nguyen, Thinh; Gross, Gilad

    2017-10-01

    The objective of this study is to determine whether ambient light serves as a fetal stimulus to decrease the amount of time needed to complete a biophysical profile. This is a randomized controlled trial of singleton gestations undergoing a biophysical profile. Patients were randomized to either ambient light or a darkened room. The primary outcome was the time needed to complete the biophysical profile. Secondary outcomes included total and individual component biophysical profile scores and scores less than 8. A subgroup analysis of different maternal body mass indices was also performed. 357 biophysical profile studies were analyzed. 182 studies were performed with ambient light and 175 were performed in a darkened room. There was no difference in the median time needed to complete the biophysical profile based on exposure to ambient light (6.1min in darkened room versus 6.6min with ambient light; P=0.73). No difference was found in total or individual component biophysical profile scores. Subgroup analysis by maternal body mass index did not demonstrate shorter study times with ambient light exposure in women who were normal weight, overweight or obese. Ambient light exposure did not decrease the time needed to complete the biophysical profile. There was no evidence that ambient light altered fetal behavior observed during the biophysical profile. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Investigation of water content in primary upper shield of high temperature engineering test reactor (HTTR)

    International Nuclear Information System (INIS)

    Sumita, Junya; Sawa, Kazuhiro; Mogi, Haruyoshi; Itahashi, Shuuji; Kitami, Toshiyuki; Akutu, Youichi; Fuchita, Yasuhiro; Kawaguchi, Toru; Moriya, Masahiro

    1999-09-01

    A primary upper shield of the High Temperature Engineering Test Reactor (HTTR) is composed of concrete (grout) which is packed into iron frames. The main function of the primary upper shield is to attenuate neutron and gamma ray from the core, that leads to satisfy dose equivalent rate limit of operating floor and stand-pipe room. Water content in the concrete is one of the most important things because it strongly affects neutron-shielding ability. Then, we carried out out-of-pile experiments to investigate relationship between temperature and water content in the concrete. Based on the experimental results, a hydrolysis-diffusion model was developed to investigate water release behavior from the concrete. The model showed that water content used for shielding design in the primary upper shield of the HTTR will be maintained if temperature during operating life is under 110degC. (author)

  15. Light Water Reactor Sustainability Program Operator Performance Metrics for Control Room Modernization: A Practical Guide for Early Design Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Ronald Boring; Roger Lew; Thomas Ulrich; Jeffrey Joe

    2014-03-01

    As control rooms are modernized with new digital systems at nuclear power plants, it is necessary to evaluate the operator performance using these systems as part of a verification and validation process. There are no standard, predefined metrics available for assessing what is satisfactory operator interaction with new systems, especially during the early design stages of a new system. This report identifies the process and metrics for evaluating human system interfaces as part of control room modernization. The report includes background information on design and evaluation, a thorough discussion of human performance measures, and a practical example of how the process and metrics have been used as part of a turbine control system upgrade during the formative stages of design. The process and metrics are geared toward generalizability to other applications and serve as a template for utilities undertaking their own control room modernization activities.

  16. Microbial diversity in European and South American spacecraft assembly clean rooms

    Science.gov (United States)

    Moissl-Eichinger, Christine; Stieglmeier, Michaela; Schwendner, Petra

    Spacecraft assembly clean rooms are unique environments for microbes: Due to low nutri-ent levels, desiccated, clean conditions, constant control of humidity and temperature, these environments are quite inhospitable to microbial life and even considered "extreme". Many procedures keep the contamination as low as possible, but these conditions are also highly se-lective for indigenous microbial communities. For space missions under planetary protection requirements, it is crucial to control the contaminating bioburden as much as possible; but for the development of novel cleaning/sterilization methods it is also important to identify and characterize (understand) the present microbial community of spacecraft clean rooms. In prepa-ration for the recently approved ESA ExoMars mission, two European and one South American spacecraft assembly clean rooms were analyzed with respect to their microbial diversity, using standard procedures, new cultivation approaches and molecular methods, that should shed light onto the presence of planetary protection relevant microorganisms. For this study, the Her-schel Space Observatory (launched in May 2009) and its housing clean rooms in Friedrichshafen (Germany), at ESTEC (The Netherlands) and CSG, Kourou (French Guyana) were sampled during assembly, test and launch operations. Although Herschel does not demand planetary protection requirements, all clean rooms were in a fully operating state during sampling. This gave us the opportunity to sample the microbial diversity under strict particulate and molecular contamination-control. Samples were collected from spacecraft and selected clean room surface areas and were subjected to cultivation assays (32 different media), molecular studies (based on 16S rRNA gene sequence analysis) and quantitative PCR. The results from different strategies will be compared and critically discussed, showing the advantages and limits of the selected methodologies. This talk will sum up the lessons

  17. Room Acoustical Fields

    CERN Document Server

    Mechel, Fridolin

    2013-01-01

    This book presents the theory of room acoustical fields and revises the Mirror Source Methods for practical computational use, emphasizing the wave character of acoustical fields.  The presented higher methods include the concepts of “Mirror Point Sources” and “Corner sources which allow for an excellent approximation of complex room geometries and even equipped rooms. In contrast to classical description, this book extends the theory of sound fields describing them by their complex sound pressure and the particle velocity. This approach enables accurate descriptions of interference and absorption phenomena.

  18. Exciton polariton spectra and limiting factors for the room-temperature photoluminescence efficiency in ZnO

    Science.gov (United States)

    Chichibu, S. F.; Uedono, A.; Tsukazaki, A.; Onuma, T.; Zamfirescu, M.; Ohtomo, A.; Kavokin, A.; Cantwell, G.; Litton, C. W.; Sota, T.; Kawasaki, M.

    2005-04-01

    Static and dynamic responses of excitons in state-of-the-art bulk and epitaxial ZnO are reviewed to support the possible realization of polariton lasers, which are coherent and monochromatic light sources due to Bose condensation of exciton-polaritons in semiconductor microcavities (MCs). To grasp the current problems and to pave the way for obtaining ZnO epilayers of improved quality, the following four principal subjects are treated: (i) polarized optical reflectance (OR), photoreflectance (PR) and photoluminescence (PL) spectra of the bulk and epitaxial ZnO were recorded at 8 K. Energies of PR resonances corresponded to those of upper and lower exciton-polariton branches, where A-, B- and C-excitons couple simultaneously to an electromagnetic wave. PL peaks due to the corresponding polariton branches were observed. Longitudinal-transverse splittings (ωLT) of the corresponding excitons were 1.5, 11.1 and 13.1 meV, respectively. The latter two values are more than two orders of magnitude greater than that of GaAs being 0.08 meV. (ii) Using these values and material parameters, corresponding vacuum-field Rabi splitting of exciton-polaritons coupled to a model MC mode was calculated to be 191 meV, which is the highest value ever reported for semiconductor MCs and satisfies the requirements to observe the strong exciton-light coupling regime necessary for polariton lasing above room temperature. (iii) Polarized OR and PR spectra of an out-plane nonpolar (1\\,1\\,\\bar{2}\\,0) ZnO epilayer grown by laser-assisted molecular beam epitaxy (L-MBE) were measured, since ZnO quantum wells (QWs) grown in nonpolar orientations are expected to show higher emission efficiencies due to the elimination of spontaneous and piezoelectric polarization fields normal to the QW plane. They exhibited in-plane anisotropic exciton resonances according to the polarization selection rules for anisotropically-strained wurzite material. (iv) Impacts of point defects on the nonradiative

  19. Virtual Seminar Room

    DEFF Research Database (Denmark)

    Forchhammer, Søren Otto; Fosgerau, Anders; Hansen, Peter Søren Kirk

    1999-01-01

    The initial design considerations and research goals for an ATM network based virtual seminar room with 5 sites are presented.......The initial design considerations and research goals for an ATM network based virtual seminar room with 5 sites are presented....

  20. Adaptive lighting controllers using smart sensors

    Science.gov (United States)

    Papantoniou, Sotiris; Kolokotsa, Denia; Kalaitzakis, Kostas; Cesarini, Davide Nardi; Cubi, Eduard; Cristalli, Cristina

    2016-07-01

    The aim of this paper is to present an advanced controller for artificial lights evaluated in several rooms in two European Hospitals located in Chania, Greece and Ancona, Italy. Fuzzy techniques have been used for the architecture of the controller. The energy efficiency of the controllers has been calculated by running the controller coupled with validated models of the RADIANCE back-wards ray tracing software. The input of the controller is the difference between the current illuminance value and the desired one, while the output is the change of the light level that should be applied in the artificial lights. Simulation results indicate significant energy saving potentials. Energy saving potential is calculated from the comparison of the current use of the artificial lights by the users and the proposed one. All simulation work has been conducted using Matlab and RADIANCE environment.

  1. Wireless Occupancy Sensors for Lighting Controls: An Applications Guide for Federal Facility Managers

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-03-15

    This guide provides federal facility managers with an overview of the energy savings potential of wireless lighting occupancy sensors for various room types, cost considerations, key steps to successful installation of wireless sensors, pros and cons of various technology options, light source considerations, and codes and standards.

  2. Visible light-induced OH radicals in Ga2O3: an EPR study.

    Science.gov (United States)

    Tzitrinovich, Zeev; Lipovsky, Anat; Gedanken, Aharon; Lubart, Rachel

    2013-08-21

    Reactive oxygen species (ROS) were found to exist in water suspensions of several metal oxide nanoparticles (NPs), such as CuO, TiO2 and ZnO. Visible light irradiation enhanced the capability of TiO2 and ZnO NPs to generate ROS, thus increasing their antibacterial effects. Because of the possible toxic effects on the host tissue it is desired to find nano-metal oxides which do not produce ROS under room light, but only upon a strong external stimulus. Using the technique of electron-spin resonance (ESR) coupled with spin trapping, we examined the ability of Ga2O3 submicron-particle suspensions in water to produce reactive oxygen species with and without visible light irradiation. We found that in contrast to ZnO and TiO2 NPs, no ROS are produced by Ga2O3 under room light. Nevertheless blue light induced hydroxyl radical formation in Ga2O3. This finding might suggest that NPs of Ga2O3 could be used safely for infected skin sterilization.

  3. Ultraviolet susceptibility of BCG and virulent tubercle bacilli

    International Nuclear Information System (INIS)

    Riley, R.L.; Knight, M.; Middlebrook, G.

    1976-01-01

    To test the effectiveness of irradiating the upper air of a room with ultraviolet light at reducing the concentration of airborne tubercle bacilli, the susceptibility to the germicidal effects of ultraviolet light, Z, was determined for various mycobacteria. Virulent tubercle bacilli and bacille Calmette-Guerin (BCG) were susceptible to ultraviolet radiation, whereas Mycobacterium phlei had 10 times their resistance (Z, approximately one-tenth that for M. tuberculosis). The effectiveness against BCG of upper air ultraviolet irradiation in a room was tested directly by nebulizing BCG into the air of the room and monitoring its rate of disappearance. With one 17-watt fixture operating, the rate of disappearance increased 6-fold; with 2 fixtures operating (46 watts total), the rate of disappearance increased 9-fold. This implies that under steady-state conditions, the concentrations of airborne organisms with ultraviolet light(s) on would have been one-sixth and one-ninth, respectively. The increase in rate of decay of the airborne organism using 1 fixture was equivalent to 10 air changes per hour, whereas that using 2 fixtures was approximately 25 air changes per hour (range: 18 to 33 air changes per hour). These increments are less than those reported previously for Serratia marcescens, because the Z value for BCG is approximately one-seventh that for serratia. These findings with BCG are believed to be directly applicable to virulent tubercle bacilli

  4. Green light drives leaf photosynthesis more efficiently than red light in strong white light: revisiting the enigmatic question of why leaves are green.

    Science.gov (United States)

    Terashima, Ichiro; Fujita, Takashi; Inoue, Takeshi; Chow, Wah Soon; Oguchi, Riichi

    2009-04-01

    The literature and our present examinations indicate that the intra-leaf light absorption profile is in most cases steeper than the photosynthetic capacity profile. In strong white light, therefore, the quantum yield of photosynthesis would be lower in the upper chloroplasts, located near the illuminated surface, than that in the lower chloroplasts. Because green light can penetrate further into the leaf than red or blue light, in strong white light, any additional green light absorbed by the lower chloroplasts would increase leaf photosynthesis to a greater extent than would additional red or blue light. Based on the assessment of effects of the additional monochromatic light on leaf photosynthesis, we developed the differential quantum yield method that quantifies efficiency of any monochromatic light in white light. Application of this method to sunflower leaves clearly showed that, in moderate to strong white light, green light drove photosynthesis more effectively than red light. The green leaf should have a considerable volume of chloroplasts to accommodate the inefficient carboxylation enzyme, Rubisco, and deliver appropriate light to all the chloroplasts. By using chlorophylls that absorb green light weakly, modifying mesophyll structure and adjusting the Rubisco/chlorophyll ratio, the leaf appears to satisfy two somewhat conflicting requirements: to increase the absorptance of photosynthetically active radiation, and to drive photosynthesis efficiently in all the chloroplasts. We also discuss some serious problems that are caused by neglecting these intra-leaf profiles when estimating whole leaf electron transport rates and assessing photoinhibition by fluorescence techniques.

  5. ISOLATION ANTHOCYANIN FROM ROSELLE PETALS (Hibiscus sabdariffa L AND THE EFFECT OF LIGHT ON THE STABILITY

    Directory of Open Access Journals (Sweden)

    Siti Nuryanti

    2012-06-01

    Full Text Available This study was conducted to isolate anthocyanins from roselle petals and testing the stability toward light. Isolation of anthocyanin was accomplished by extracting roselle petals using eluents with different polarity levels. Nonpolar compounds was eliminated using n-hexane, then semipolar compounds extracted with ethyl acetate and isolated anthocyanin by solvent mixtures of methanol-HCl 0.5%. Color test to determine the presence of anthocyanin was performed with NH3 vapor, Pb-acetate 1% and Pb-nitrate 5%. The structure of anthocyanin in the roselle flower was determined using UV-Vis spectrophotometer, FT-IR and 1H-NMR. Anthocyanin stability test of the influence of light carried out in a room without light conditions (dark room and light 25 Watt at 31 °C. The results showed that the roselle petals contain anthocyanin cyanidin-3-glucoside. Light has been found to affect the stability of anthocyanin cyanidin-3-glucoside.

  6. Optical Diode Effect at Spin-Wave Excitations of the Room-Temperature Multiferroic BiFeO_{3}.

    Science.gov (United States)

    Kézsmárki, I; Nagel, U; Bordács, S; Fishman, R S; Lee, J H; Yi, Hee Taek; Cheong, S-W; Rõõm, T

    2015-09-18

    Multiferroics permit the magnetic control of the electric polarization and the electric control of the magnetization. These static magnetoelectric (ME) effects are of enormous interest: The ability to read and write a magnetic state current-free by an electric voltage would provide a huge technological advantage. Dynamic or optical ME effects are equally interesting, because they give rise to unidirectional light propagation as recently observed in low-temperature multiferroics. This phenomenon, if realized at room temperature, would allow the development of optical diodes which transmit unpolarized light in one, but not in the opposite, direction. Here, we report strong unidirectional transmission in the room-temperature multiferroic BiFeO_{3} over the gigahertz-terahertz frequency range. The supporting theory attributes the observed unidirectional transmission to the spin-current-driven dynamic ME effect. These findings are an important step toward the realization of optical diodes, supplemented by the ability to switch the transmission direction with a magnetic or electric field.

  7. Quality attributes of starfruit (Averrhoa carambola L.) juice treated with ultraviolet radiation.

    Science.gov (United States)

    Bhat, Rajeev; Ameran, Suhaida Binti; Voon, Han Ching; Karim, A A; Tze, Liong Min

    2011-07-15

    Starfruit juice were exposed to ultraviolet (UV-C) light for 0, 30 and 60min at room temperature (25±1°C). On exposure, the titratable acidity significantly decreased, while the decrease in °Brix and pH were not significant. With regard to colorimetric parameters, L(∗) value increased significantly with a subsequent decrease in a(∗) and b(∗) values corresponding to UV treatment time. Except for the ascorbic acid, other antioxidants measured (% DPPH inhibition, total phenols, flavonols, flavonoids and antioxidant capacity) showed enhancement on expsoure to UV (significant at 60min). Microbial studies showed reduction in APC, yeasts and mould counts by 2-log cycle on UV treatments. These results supports the application of UV as a measure of non-thermal and physical food preservation technique for starfruit juice that can be explored commercially to benefit both the producers and consumers. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Injury by lighting gas on horticultural crops

    Energy Technology Data Exchange (ETDEWEB)

    Berge, H.

    1971-01-01

    The different effects of underground and above ground lighting gas emissions on horticultural plants in greenhouses or rooms are described. A special fertilization scheme for recovery of injured plants was especially effective in Asparagus sp. and Rhododendron sp. The use of a gas detector apparatus for identification of underground gas emissions is mentioned.

  9. PROPOSAL OF A CLINICAL CARE PATHWAY FOR THE MANAGEMENT OF ACUTE UPPER GASTROINTESTINAL BLEEDING

    Directory of Open Access Journals (Sweden)

    Matheus Cavalcante FRANCO

    2015-12-01

    Full Text Available Background - Upper gastrointestinal bleeding implies significant clinical and economic repercussions. The correct establishment of the latest therapies for the upper gastrointestinal bleeding is associated with reduced in-hospital mortality. The use of clinical pathways for the upper gastrointestinal bleeding is associated with shorter hospital stay and lower hospital costs. Objective - The primary objective is the development of a clinical care pathway for the management of patients with upper gastrointestinal bleeding, to be used in tertiary hospital. Methods - It was conducted an extensive literature review on the management of upper gastrointestinal bleeding, contained in the primary and secondary information sources. Results - The result is a clinical care pathway for the upper gastrointestinal bleeding in patients with evidence of recent bleeding, diagnosed by melena or hematemesis in the last 12 hours, who are admitted in the emergency rooms and intensive care units of tertiary hospitals. In this compact and understandable pathway, it is well demonstrated the management since the admission, with definition of the inclusion and exclusion criteria, passing through the initial clinical treatment, posterior guidance for endoscopic therapy, and referral to rescue therapies in cases of persistent or rebleeding. It was also included the care that must be taken before hospital discharge for all patients who recover from an episode of bleeding. Conclusion - The introduction of a clinical care pathway for patients with upper gastrointestinal bleeding may contribute to standardization of medical practices, decrease in waiting time for medications and services, length of hospital stay and costs.

  10. Guidelines for control room design reviews

    International Nuclear Information System (INIS)

    1981-09-01

    The control room design review is part of a broad program being undertaken by the nuclear industry and the government to ensure consideration of human factors in nuclear power plant design and operation. The purpose of the control room design review described by these guidelines is to (1) review and evaluate the control room workspace, instrumentation, controls, and other equipment from a human factors engineering point of view that takes into account both system demands and operator capabilities; and (2) to identify, assess, and implement control room design modifications that correct inadequate or unsuitable items. The scope of the control room design review described by these guidelines covers the human engineering review of completed control rooms; i.e., operational control rooms or those at that stage of the licensing process where control room design and equipment selection are committed. These guidelines should also be of use during the design process for new control rooms. However, additional analyses to optimize the allocation of functions to man and machine, and further examination of advanced control system technology, are recommended for new control rooms. Guidelines and references for comprehensive system analyses designed to incorporate human factors considerations into the design and development of new control rooms are presented in Appendix B. Where possible, a generic approach to the control room design review process is encouraged; for example, when control room designs are replicated wholly or in part in two or more units. Even when designs are not replicated exactly, generic reviews which can be modified to account for specific differences in particular control rooms should be considered. Industry organizations and owners groups are encouraged to coordinate joint efforts and share data to develop generic approaches to the design review process. The control room design review should accomplish the following specific objectives. To determine

  11. Chemical reaction networks as a model to describe UVC- and radiolytically-induced reactions of simple compounds.

    Science.gov (United States)

    Dondi, Daniele; Merli, Daniele; Albini, Angelo; Zeffiro, Alberto; Serpone, Nick

    2012-05-01

    When a chemical system is submitted to high energy sources (UV, ionizing radiation, plasma sparks, etc.), as is expected to be the case of prebiotic chemistry studies, a plethora of reactive intermediates could form. If oxygen is present in excess, carbon dioxide and water are the major products. More interesting is the case of reducing conditions where synthetic pathways are also possible. This article examines the theoretical modeling of such systems with random-generated chemical networks. Four types of random-generated chemical networks were considered that originated from a combination of two connection topologies (viz., Poisson and scale-free) with reversible and irreversible chemical reactions. The results were analyzed taking into account the number of the most abundant products required for reaching 50% of the total number of moles of compounds at equilibrium, as this may be related to an actual problem of complex mixture analysis. The model accounts for multi-component reaction systems with no a priori knowledge of reacting species and the intermediates involved if system components are sufficiently interconnected. The approach taken is relevant to an earlier study on reactions that may have occurred in prebiotic systems where only a few compounds were detected. A validation of the model was attained on the basis of results of UVC and radiolytic reactions of prebiotic mixtures of low molecular weight compounds likely present on the primeval Earth.

  12. Effect of UV-C radiation on bioactive compounds of pineapple (Ananas comosus L. Merr.) by-products.

    Science.gov (United States)

    Freitas, Ana; Moldão-Martins, Margarida; Costa, Helena S; Albuquerque, Tânia G; Valente, Ana; Sanches-Silva, Ana

    2015-01-01

    The industrial processing of pineapple generates a high quantity of by-products. To reduce the environmental impact of these by-products and the inherent cost of their treatment, it is important to characterise and valorise these products, converting them into high added value products. Ultra-violet radiation is one of the main sustainable sanitation techniques for fruits. Since this radiation can induce plant stress which can promote the biosynthesis of bioactive compounds, it is important to evaluate its effect in fruits. The amounts of vitamins (C and E) and carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lutein, lycopene, neoxanthin, violaxanthin and zeaxanthin) in pineapple by-products (core and rind) were analysed before and after treatment with UV radiation. All treated and untreated pineapple by-products contained β-carotene as the main carotenoid (rind, 2537-3225 µg; and core, 960-994 µg 100 g(-1) DW). Pineapple rind also contained lutein (288-297 µg 100 g(-1) DW) and α-carotene (89-126 µg 100 g(-1) DW). The results provide evidence of the potential of pineapple by-products as a source of bioactive compounds with antioxidant activity, which can be used by pharmaceutical, cosmetics and food industries. In addition, UV-C was shown to be a treatment that can add nutritional value to pineapple by-products. © 2014 Society of Chemical Industry.

  13. Unconditional polarization qubit quantum memory at room temperature

    Science.gov (United States)

    Namazi, Mehdi; Kupchak, Connor; Jordaan, Bertus; Shahrokhshahi, Reihaneh; Figueroa, Eden

    2016-05-01

    The creation of global quantum key distribution and quantum communication networks requires multiple operational quantum memories. Achieving a considerable reduction in experimental and cost overhead in these implementations is thus a major challenge. Here we present a polarization qubit quantum memory fully-operational at 330K, an unheard frontier in the development of useful qubit quantum technology. This result is achieved through extensive study of how optical response of cold atomic medium is transformed by the motion of atoms at room temperature leading to an optimal characterization of room temperature quantum light-matter interfaces. Our quantum memory shows an average fidelity of 86.6 +/- 0.6% for optical pulses containing on average 1 photon per pulse, thereby defeating any classical strategy exploiting the non-unitary character of the memory efficiency. Our system significantly decreases the technological overhead required to achieve quantum memory operation and will serve as a building block for scalable and technologically simpler many-memory quantum machines. The work was supported by the US-Navy Office of Naval Research, Grant Number N00141410801 and the Simons Foundation, Grant Number SBF241180. B. J. acknowledges financial assistance of the National Research Foundation (NRF) of South Africa.

  14. Influence of intensive light exposure on the complex impedance of polymer light-emitting diodes

    Directory of Open Access Journals (Sweden)

    Fábio Rogério Cury

    2008-06-01

    Full Text Available In this work we investigated the effect of visible radiation on the electrical properties of poly[(2-methoxy-5-hexyloxy-p-phenylenevinylene]- MH-PPV films and light emitting diodes. Complex impedance measurements of (Au or ITO/MH-PPV/(Au or Al samples were carried out at room temperature and exposed to white light. Over the frequency range from 100 mHz to 2 MHz, the electrical results of Au/MH-PPV/Au was dominated by the Cole-Cole approach, where the electrode influence is negligible. However, some additional influence of the interface was observed to occur when Al was used as electrode. These effects were observed under both dark and visible-light illumination conditions. A simple model based on resistor-capacitor parallel circuits was developed to represent the complex impedance of the samples, thereby separating bulk and interface contributions. We observed that the polymer electrical resistivity decreased while the dielectric constant of the polymer and the thickness of the Al/MH-PPV layer were almost constant with increasing light intensity. The decrease of the polymer layer resistance comes from a better charge injection due to a light induced dissociation of positive charge carriers at the electrode.

  15. CSN's New Emergency Room

    International Nuclear Information System (INIS)

    Sendin, P.

    2005-01-01

    During the month of July 2005 the physical renovation works and technological updating of the basic infrastructures of the CSN Emergency Room (SALEM) were finished, allowing the Room to now have greater functionality and a broader technical capacity. Nevertheless, the technological improvement process of SALEM will reach its full potential within the next few years, once the installation currently underway of the new information integration and monitoring systems and the decision making support systems have been completed. This article describes the improvements introduced to the Room and the objectives pursued in this renovation project to convert the SALEM into a new generation room in accordance with its current technological context. (Author) 4 refs

  16. Our Urban Living Room

    DEFF Research Database (Denmark)

    Hjortshøj, Rasmus

    2016-01-01

    Our Urban Living Room is an exhibition and a book, created by Cobe. The theme is based on Cobe’s ten years of practice, grounded in social livability and urban democracy, and our aim to create buildings and spaces that invite Copenhageners to use and define them; as an extended living room, where...... the boundaries between private and public space become fluid. Based on specific Cobe projects, Our Urban Living Room tells stories about the architectural development of Copenhagen, while exploring the progression of the Danish Capital - from an industrial city into an urban living room, known as one...... of the world’s most livable places. Photography by Rasmus Hjortshøj....

  17. Gas explosion in a room with a window and passage to an adjacent room

    Directory of Open Access Journals (Sweden)

    Polandov Yuri

    2016-01-01

    Full Text Available Some publications describe an effect, produced during a physical model experiment, when an adjacent gas-free room influences the gas explosion pressure in a room with a window. The explosion pressure in this case significantly exceeds (2.5 times the explosion pressure in a room without an adjacent room. This result has been confirmed by our studies. Based on other available information about the influence of the ignition point location on the explosion pressure in one room, it was suggested that this could be true for an explosion in two rooms. In our studies we used a test unit with two connected chambers, each having a volume of 1.125 m3. It turned out that this influence of the adjacent volume was not so unambiguous as it was described in those publications. It was found out that the maximum effect of explosion pressure amplification by the adjacent room is achieved, when the igniter is located in the chamber filled with a gas-air mixture in the area between the center of the chamber and the window (maximum amplification by more than 3 times. This effect is lower directly by the window (1.8 times and is practically absent in case of ignition within the area near the passage connecting the chamber with the adjacent room. This suggests that the effect discovered earlier is a special case of the general dependence of the gas explosion pressure in two chambers on the igniter location.

  18. Study on the living environment of semi-underground room with attached green house; Fusetsu onshitsu no aru hanchikashitsu no kyojusei ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T; Tsukayama, N [Ochanomizu University, Tokyo (Japan)

    1996-10-27

    In response to demand for the expansion of living space, the living environment of semi-underground room has been investigated. An attached green house (passive solar house) is adjacent to the semi-underground room. This is reinforced concrete construction, having flat type solar collector on its roof and lighting window in its north side. It does not have artificial air conditioners. Based on the measurements of daylight factor, artificial lighting is not required at the window in the daytime, but it is desirable to use daylight and artificial lighting together at the center. The performance of sound insulation depends on the high performance soundproof sash level. There is less daily temperature variation due to its large heat capacity, and less yearly temperature variation than the outside. By shielding the solar radiation, the insolation in the green house in summer can be restricted in the same as in winter. The insolation can be easily received in winter due to its large vertical intensity of solar radiation. The green house in the south side is useful for improving the living environment of semi-underground room. The temperature rise in the semi-underground room can be restricted by opening window in summer. It is desirable for the comfortable living to use artificial cooling to reduce the daytime temperature by 3 to 4{degree}C. In winter, it is comfortable to heat by 4 to 5{degree}C. 2 refs., 7 figs.

  19. Fast and slow light property improvement in erbium-doped amplifier

    Science.gov (United States)

    Peng, P. C.; Wu, F. K.; Kao, W. C.; Chen, J.; Lin, C. T.; Chi, S.

    2013-01-01

    This work experimentally demonstrates improvement of the fast light property in erbium-doped amplifiers at room temperature. The difference between the signal power and the pump power associated with bending loss is used to control the signal power at the different positions of the erbium-doped fiber (EDF) to improve the fast light property. Periodic bending of the EDF increases the time advance of the probe signal by over 288%. Additionally, this concept also could improve the fast light property using coherent population oscillations in semiconductor optical amplifiers.

  20. Sensitivity of the human circadian pacemaker to nocturnal light: melatonin phase resetting and suppression

    Science.gov (United States)

    Zeitzer, J. M.; Dijk, D. J.; Kronauer, R.; Brown, E.; Czeisler, C.

    2000-01-01

    Ocular exposure to early morning room light can significantly advance the timing of the human circadian pacemaker. The resetting response to such light has a non-linear relationship to illuminance. The dose-response relationship of the human circadian pacemaker to late evening light of dim to moderate intensity has not been well established. Twenty-three healthy young male and female volunteers took part in a 9 day protocol in which a single experimental light exposure6.5 h in duration was given in the early biological night. The effects of the light exposure on the endogenous circadian phase of the melatonin rhythm and the acute effects of the light exposure on plasma melatonin concentration were calculated. We demonstrate that humans are highly responsive to the phase-delaying effects of light during the early biological night and that both the phase resetting response to light and the acute suppressive effects of light on plasma melatonin follow a logistic dose-response curve, as do many circadian responses to light in mammals. Contrary to expectations, we found that half of the maximal phase-delaying response achieved in response to a single episode of evening bright light ( approximately 9000 lux (lx)) can be obtained with just over 1 % of this light (dim room light of approximately 100 lx). The same held true for the acute suppressive effects of light on plasma melatonin concentrations. This indicates that even small changes in ordinary light exposure during the late evening hours can significantly affect both plasma melatonin concentrations and the entrained phase of the human circadian pacemaker.

  1. Performance evaluation of control room HVAC and air cleaning systems under accident conditions

    International Nuclear Information System (INIS)

    Almerico, F.; Machiels, A.J.; Ornberg, S.C.; Lahti, G.P.

    1985-01-01

    In light water reactors, control rooms and technical support centers must be designed to provide habitable environments in accordance with the requirements specified in General Design Criterion 19 of Appendix A, 10 CFR Part 50. Therefore, the effectiveness of HVAC and air cleaning system designs with respect to plant operator protection has to be evaluated by the system designer. Guidance for performing the analysis has been previously given in ANSI/ASME N509-1980 as well as in presentations at past Air Cleaning Conferences. The previous work is extended and the methodology used in a generic, interactive computer program that performs Main Control Room and Technical Support Center (TSC) habitability analyses for LWR nuclear power plants is presented. For given accident concentrations of radionuclides or hazardous gases in the outdoor air intakes and plant spaces surrounding the Main Control Room (or TSC), the program models the performance of the HVAC and air cleaning system designs, and determines control room (or TSC) contaminant concentrations and plant operator protection factors. Calculated or actual duct leakage, air cleaning efficiency, and airborne contamination are taken into account. Flexibility of the model allows for the representation of most control rooms (or TSC) and associated HVAC and air cleaning system conceptual designs that have been used by the US architect/engineers. The program replaced tedious calculations to determine the effects of HVAC ductwork and equipment leakage and permits (1) parametric analyses of various HVAC system design options early in the conceptual phase of a project, and (2) analysis of the effects of leakage test results on contaminant room concentrations, and therefore operator doses

  2. More room for ISOLDE

    CERN Multimedia

    2005-01-01

    To meet the needs of the new ISOLDE experiments, a new extension has been added to the facility's Building 170. The new extension to Building 170. Moving around the ISOLDE hall was almost like an obstacle course until now. The facility's Building 170 simply didn't have an inch to spare and the ISOLDE team's need to set up new experiments, whose installation could have created difficulties from the safety point of view, only exacerbated the problem. "We had ambitious plans to develop new experiments but no room for them", says Mats Lindroos, ISOLDE's technical coordinator. The only solution was to extend the existing building". This was how a new building saw the light of day. Measuring 24 metres long, 20 metres wide and 12 metres high, it is an extension to the existing Building 170 and should be ready for use this year. The new structure makes use of the existing infrastructure, with part of the end wall of Building 170 being kept as a support for steel platforms. The top of this wall had to be cut away ...

  3. Physical environment design criteria for the new control room in the ENEA TRIGA-RC1 plant

    International Nuclear Information System (INIS)

    Alberti, M.; Di Giulio, A.

    1986-01-01

    Parallelly to the plant modifications, many changes of the instrumentation in the Control Room (CR) were necessary in order to deal with the various aged components and the completion and integration needs turning out from the experience in reactor running. In the room, besides the control activity of the RC1 plant, continuous training and updating activities are currently performed which are intended for the operators working in the control rooms of nuclear power plants. The design of the physical environment of the new CR - carried out in a more general research project between ENEA and Politecnico di Milano - was based on the following fundamental criteria: - to ensure conditions fit for the performance of the suspervision, diagnosis and control tasks the operators are entrusted with; - to set up a model of control room for the more complex power plants. First of all a detailed analysis of the environmental conditions relating to microclimate, lighting and noise was accomplished. Afterwards, the goals to be attained were defined as well as the technical means necessary for providing the operators with comfortable working conditions

  4. Evaluating the auralization of a small room in a virtual sound environment using objective room acoustic measures

    DEFF Research Database (Denmark)

    Ahrens, Axel; Marschall, Marton; Dau, Torsten

    2016-01-01

    To study human auditory perception in realistic environments, loudspeaker-based reproduction techniques have recently become state-of-the-art. To evaluate the accuracy of a simulation-based room auralization of a small room, objective measures, such as early-decay-time (EDT), reverberation time...... of the room. The auralizations were generated using the loudspeaker-based room auralization toolbox (LoRA; Favrot and Buchholz, 2010) and reproduced in a 64-channel loudspeaker array, set up in an anechoic chamber. Differences between the objective measures evaluated in the real and the virtual room were......, clarity, interaural cross-correlation (IACC), and the speech transmission index were measured in an IEC listening room for 28 source-receiver combinations. The room was then modeled in the room acoustics software ODEON, and the same objective measures were also evaluated for the auralized version...

  5. Development of highly qualified UV-laser light source for rf gun

    International Nuclear Information System (INIS)

    Tomizawa, H.; Dewa, H.; Taniuchi, T.

    2004-01-01

    We have been developing stable and highly qualified UV-laser pulse as a light source of the rf gun for an injector candidate of future light sources. Our gun cavity is a single-cell pillbox, and the copper inner wall is used as a photo cathode. In present status, the short pulse energy stability of laser has been improved down to 1.3∼1.5% (rms; 10pps; 10000 shots) at the third harmonic generation. The long stability depends on the stability of modelocking at oscillator. In this improvement we just passively stabilized the system. We considered environmental controls in clean room to reduce optical damage accidents and constructed a new humidity-controlled clean room in 2003. And we re-installed the total laser system in this room in 2004. The relative humidity of this new clean room at room temperature is in a region of 50∼60 % with a stability of less than 2% (p-p). On the other hand, the ideal spatial and temporal profiles of a shot-by-shot single laser pulse are essential to suppress the emittance growth of the electron beam from a photo-cathode rf gun. This laser-shaping project has been started in two steps since 2002. As the first successful test run in 2002, with a microlens array as a simple spatial shaper, we obtained a minimum emittance value of 2π mm·mrad with a beam energy of 3.1 MeV, holding its charge to 0.1 nC/bunch. In the next test run in 2004, we prepared a deformable mirror for spatial shaping, and a spatial light modulator based on fused-silica plates for temporal shaping. We are applying the both adaptive optics to automatically shape the both spatial and temporal UV-laser profiles with a feedback routine at the same time. We report herein the principle and developing process of our laser beam quality control system. (author)

  6. submitter Technical Note: Using DEG-CPCs at upper tropospheric temperatures

    CERN Document Server

    Wimmer, D; Nieminen, T; Duplissy, J; Ehrhart, S; Almeida, J; Rondo, L; Franchin, A; Kreissl, F; Bianchi, F; Manninen, H E; Kulmala, M; Curtius, J; Petäjä, T

    2015-01-01

    Over the last few years, several condensation particle counters (CPCs) capable of measuring in the sub-3 nm size range have been developed. Here we study the performance of CPCs based on diethylene glycol (DEG) at different temperatures during Cosmics Leaving OUtdoor Droplets (CLOUD) measurements at CERN. The data shown here are the first set of verification measurements for sub-3 nm CPCs under upper tropospheric temperatures using atmospherically relevant aerosol particles. To put the results in perspective we calibrated the DEG-CPC at room temperature, resulting in a cut-off diameter of 1.4 nm. All diameters refer to mobility equivalent diameters in this paper. At upper tropospheric temperatures ranging from 246.15 K to 207.15 K, we found cut-off sizes relative to a particle size magnifier in the range of 2.5 to 2.8 nm. Due to low number concentration after size classification, the cut-off diameters have a high uncertainty (±0.3 nm) associated with them. Operating two laminar flow DEG-CPCs with different c...

  7. Lecture-Room Interference Demo Using a Glass Plate and a Laser Beam Focused on It

    Science.gov (United States)

    Ageev, Leonid A.; Yegorenkov, Vladimir D.

    2010-01-01

    We describe a simple case of non-localized interference produced with a glass plate and a laser beam focused on it. The proposed setup for observing interference is compact when semiconductor lasers are employed, and it is well suited for demonstration and comparison of interference in reflected and transmitted light in a large lecture-room. This…

  8. Fire protection for clean rooms

    International Nuclear Information System (INIS)

    Kirson, D.

    1990-01-01

    The fire protection engineer often must decide what size fire can be tolerated before automatic fire suppression systems actuate. Is it a wastepaper basket fire, a bushel basket fire...? In the case of state-of-the-art clean rooms, the answer clearly is not even an incipient fire. Minor fires in clean rooms can cause major losses. This paper discusses what a clean room is and gives a brief overview of the unique fire protection challenges encountered. The two major causes of fire related to clean rooms in the semiconductor industry are flammable/pyrophoric gas fires in plastic ducts and polypropylene wet bench fires. This paper concentrates on plastic ductwork in clean rooms, sprinkler protection in ductwork, and protection for wet benches

  9. Control room design

    International Nuclear Information System (INIS)

    Zinke, H.

    1980-01-01

    To control a 1300 megawatt nuclear power plant, about 15000 plant parameters must be collected together to control and operate the plant. The control room design therefore is of particular importance. The main design criteria are: Required functions of the power plant process - Level of Automation - Ergonomics - Available Technology. Extensive analysis has resulted in a control room design method. This ensures that an objective solution will be reached. Resulting from this methodical approach are: 1. Scope, position and appearance of the instrumentation. 2. Scope, position and appearance of the operator controls. Process analysis dictates what instrumentation and operator controls are needed. The priority and importance of the control and instrumentation (this we define as the utilisation areas), dictates the rough layout of the control room. (orig./RW)

  10. 2012 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Upper Naches River, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data of the Upper Naches River Valley and Nile Slide area of interest on September 30th,...

  11. A mechanistic model of an upper bound on oceanic carbon export as a function of mixed layer depth and temperature

    Directory of Open Access Journals (Sweden)

    Z. Li

    2017-11-01

    Full Text Available Export production reflects the amount of organic matter transferred from the ocean surface to depth through biological processes. This export is in large part controlled by nutrient and light availability, which are conditioned by mixed layer depth (MLD. In this study, building on Sverdrup's critical depth hypothesis, we derive a mechanistic model of an upper bound on carbon export based on the metabolic balance between photosynthesis and respiration as a function of MLD and temperature. We find that the upper bound is a positively skewed bell-shaped function of MLD. Specifically, the upper bound increases with deepening mixed layers down to a critical depth, beyond which a long tail of decreasing carbon export is associated with increasing heterotrophic activity and decreasing light availability. We also show that in cold regions the upper bound on carbon export decreases with increasing temperature when mixed layers are deep, but increases with temperature when mixed layers are shallow. A meta-analysis shows that our model envelopes field estimates of carbon export from the mixed layer. When compared to satellite export production estimates, our model indicates that export production in some regions of the Southern Ocean, particularly the subantarctic zone, is likely limited by light for a significant portion of the growing season.

  12. First installation of a dual-room IVR-CT system in the emergency room.

    Science.gov (United States)

    Wada, Daiki; Nakamori, Yasushi; Kanayama, Shuji; Maruyama, Shuhei; Kawada, Masahiro; Iwamura, Hiromu; Hayakawa, Koichi; Saito, Fukuki; Kuwagata, Yasuyuki

    2018-03-05

    Computed tomography (CT) embedded in the emergency room has gained importance in the early diagnostic phase of trauma care. In 2011, we implemented a new trauma workflow concept with a sliding CT scanner system with interventional radiology features (IVR-CT) that allows CT examination and emergency therapeutic intervention without relocating the patient, which we call the Hybrid emergency room (Hybrid ER). In the Hybrid ER, all life-saving procedures, CT examination, damage control surgery, and transcatheter arterial embolisation can be performed on the same table. Although the trauma workflow realized in the Hybrid ER may improve mortality in severe trauma, the Hybrid ER can potentially affect the efficacy of other in/outpatient diagnostic workflow because one room is occupied by one severely injured patient undergoing both emergency trauma care and CT scanning for long periods. In July 2017, we implemented a new trauma workflow concept with a dual-room sliding CT scanner system with interventional radiology features (dual-room IVR-CT) to increase patient throughput. When we perform emergency surgery or interventional radiology for a severely injured or ill patient in the Hybrid ER, the sliding CT scanner moves to the adjacent CT suite, and we can perform CT scanning of another in/outpatient. We believe that dual-room IVR-CT can contribute to the improvement of both the survival of severely injured or ill patients and patient throughput.

  13. Effort-reward imbalance at work and self-rated health of Las Vegas hotel room cleaners.

    Science.gov (United States)

    Krause, Niklas; Rugulies, Reiner; Maslach, Christina

    2010-04-01

    This study investigates the relationship between effort-reward-imbalance (ERI) at work and self-rated health (SF-36) among 941 Las Vegas hotel room cleaners (99% female, 84% immigrant). Logistic regression models adjust for age, health behaviors, physical workload and other potential confounders. 50% reported ERI and 60% poor or fair general health. Significant associations were found between ERI and all SF-36 health measures. Workers in the upper quartile of the efforts/rewards ratio were 2-5 times more likely to experience poor or fair general health, low physical function, high levels of pain, fatigue, and role limitations due to physical and mental health problems. The cross-sectional design limits causal interpretation of these associations. However, the development of interventions to reduce ERI and to improve general health among room cleaners deserves high priority considering that both high ERI and low self-rated health have predicted chronic diseases and mortality in prospective studies. (c) 2009 Wiley-Liss, Inc.

  14. The energy saving potential of occupancy-based lighting control strategies in open-plan offices: the influence of occupancy patterns

    NARCIS (Netherlands)

    de Bakker, C.; van de Voort, T.; Rosemann, A.L.P.

    2018-01-01

    Occupancy-based lighting control strategies have been proven to be effective in diminishing offices’ energy consumption. These strategies have typically worked by controlling lighting at the room level but, recently, lighting systems have begun to be equipped with sensors on a more fine-grained

  15. Revised accident source terms and control room habitability

    International Nuclear Information System (INIS)

    Lahti, G.P.; Hubner, R.S.; Johnson, W.J.; Schwartz, B.C.

    1993-01-01

    In April 1992, the NRC staff presented to the Commissioners the draft NUREG open-quotes Revised Accident Source Terms for Light-Water Nuclear Power Plants.close quotes This document is the culmination of more than ten years of NRC-sponsored research and represents the first change in the NRC's position on source terms since TID-14844 was issued in 1962. The purpose of this paper is to investigate the impact of the revised source terms on the current approach to analyzing control room habitability as required by 10 CFR 50. Sample calculations are presented that identify aspects of the model requiring clarification before the implementation of the revised source terms. 6 refs., 4 tabs

  16. Complex Sensory Corpuscles in the Upper Jaw of Horsfield’s Tortoise (Testudo horsfieldii

    Directory of Open Access Journals (Sweden)

    Marcela Buchtová

    2009-01-01

    Full Text Available The sensory corpuscles of Testudo horsfieldii in the skin of the upper lip and face were studied with light and electron microscopy. The sensory corpuscles were situated under epidermis; in the corium and also between the upper jaw bone tissues in the rostral part of oral cavity. The skin sensory corpuscles with a ramified inner core were grouped in clusters. Within the corpuscle there were several simple inner cores embedded within a common superficial capsule. The complex corpuscles have a novel structure in comparison to what has been described for sensory nerve endings in turtle. The complex sensory corpuscles probably function as mechanoreceptors important for monitoring the movement of the keratinized ridges and the most rostral part of the upper jaw, the rhamphotheci.

  17. Nuclear power plant control room operator control and monitoring tasks

    International Nuclear Information System (INIS)

    Bovell, C.R.; Beck, M.G.; Carter, R.J.

    1998-01-01

    Oak Ridge National Laboratory is conducting a research project the purpose of which is to develop the technical bases for regulatory review criteria for use in evaluating the safety implications of human factors associated with the use of artificial intelligence and expert systems, and with advanced instrumentation and control (I and C) systems in nuclear power plants (NPP). This report documents the results from Task 8 of that project. The primary objectives of the task was to identify the scope and type of control and monitoring tasks now performed by control-room operators. Another purpose was to address the types of controls and safety systems needed to operate the nuclear plant. The final objective of Task 8 was to identify and categorize the type of information and displays/indicators required to monitor the performance of the control and safety systems. This report also discusses state-of-the-art controls and advanced display devices which will be available for use in control-room retrofits and in control room of future plants. The fundamental types of control and monitoring tasks currently conducted by operators can be divided into four classifications: function monitoring tasks, control manipulation tasks, fault diagnostic tasks, and administrative tasks. There are three general types of controls used in today's NPPs, switches, pushbuttons, and analog controllers. Plant I and C systems include components to achieve a number of safety-related functions: measuring critical plant parameters, controlling critical plant parameters within safety limits, and automatically actuating protective devices if safe limits are exceeded. The types of information monitored by the control-room operators consist of the following parameters: pressure, fluid flow and level, neutron flux, temperature, component status, water chemistry, electrical, and process and area radiation. The basic types of monitoring devices common to nearly all NPP control rooms include: analog meters

  18. The Virtual Dressing Room

    DEFF Research Database (Denmark)

    Holte, Michael Boelstoft; Gao, Yi; Petersson, Eva

    2015-01-01

    This paper presents the design and evaluation of a usability and user experience test of a virtual dressing room. First, we motivate and introduce our recent developed prototype of a virtual dressing room. Next, we present the research and test design grounded in related usability and user...... experience studies. We give a description of the experimental setup and the execution of the designed usability and user experience test. To this end, we report interesting results and discuss the results with respect to user-centered design and development of a virtual dressing room....

  19. Experimental Demonstration and Theoretical Analysis of Slow Light in a Semiconductor Waveguide at GHz Frequencies

    DEFF Research Database (Denmark)

    Mørk, Jesper; Kjær, Rasmus; Poel, Mike van der

    2005-01-01

    Experimental demonstration and theoretical analysis of slow light in a semiconductor waveguide at GHz frequencies slow-down of light by a factor of two in a semiconductor waveguide at room temperature with a bandwidth of 16.7 GHz using the effect of coherent pulsations of the carrier density...

  20. Bacterial and fungal endophthalmitis in upper Egypt: related species and risk factors.

    Science.gov (United States)

    Gharamah, A A; Moharram, A M; Ismail, M A; Al-Hussaini, A K

    2012-08-01

    To study risk factors, contributing factors of bacterial and fungal endophthalmitis in Upper Egypt, test the isolated species sensitive to some therapeutic agents, and to investigate the air-borne bacteria and fungi in opthalmology operating rooms. Thirty one cases of endophthalmitis were clinically diagnosed and microbiologically studied. Indoor air-borne bacteria and fungi inside four air-conditioned operating rooms in the Ophthalmology Department at Assiut University Hospitals were also investigated. The isolated microbes from endophthalmitis cases were tested for their ability to produce some extracellular enzymes including protease, lipase, urease, phosphatase and catalase. Also the ability of 5 fungal isolates from endophthalmitis origin to produce mycotoxins and their sensitivity to some therapeutic agents were studied. Results showed that bacteria and fungi were responsihle for infection in 10 and 6 cases of endophthalmitis, respectively and only 2 cases produced a mixture of bacteria and fungi. Trauma was the most prevalent risk factor of endophthalmitis where 58.1% of the 31 cases were due to trauma. In ophthalmology operating rooms, different bacterial and fungal species were isolated. 8 bacterial and 5 fungal isolates showed their ability to produce enzymes while only 3 fungal isolates were able to produce mycotoxins. Terbinafine showed the highest effect against most isolates in vitro. The ability of bacterial and fungal isolates to produce extracellular enzymes and mycotoxins may be aid in the invasion and destruction of eye tissues. Microbial contamination of operating rooms with air-borne bacteria and fungi in the present work may be a source of postoperative endophthalmitis.